Amiodarone amp 50mg/ml 3ml N10 (Borisov)
Medicines that can cause torsades de pointes are primarily class Ia and class III antiarrhythmic drugs and some antipsychotics. Hypokalemia is a predisposing factor, as well as bradycardia or congenital or acquired prolongation of the QT interval. Combinations with - Drugs that can cause torsade de pointes (TdP) are contraindicated. - Class Ia antiarrhythmic drugs (quinidine, hydroquinidine, isopyramide). - Class Ia antiarrhythmic drugs. III (dofetilide, ibutilide, sotalol). - Other drugs, such as bepridil, cisapride, difemanil, IV ritromycin, mizolastine, IV vincamine, moxifloxacin, IV spiramycin. - Sultopride. Increases the risk of ventricular rhythm disturbances (tachycardia type "pirouette"). These contraindications do not apply to the use of amiodarone for cardiopulmonary resuscitation in the event of cardiac arrest resistant to electrical defibrillation. Not recommended combinations with Cyclosporine Possible increase in the level of cyclosporine in plasma associated with a decrease in the metabolism of the drug in the liver, with possible nephrotoxic manifestations .Determining the level of cyclosporine in the blood, checking renal function and reviewing the dosage during treatment with amiodarone and after discontinuation of the drug. Diltiazem for injection Risk of bradycardia and atrioventricular block. If the combination is unavoidable, strict clinical and continuous ECG monitoring must be established. Verapamil for injection Risk of bradycardia and atrioventricular block. If a combination is unavoidable, it is necessary to establish strict clinical and constant ECG monitoring. Antiparasitic drugs that can cause torsades de pointes (halofantrine, pentamidine, lumefantrine) If the combination is unavoidable, preliminary control of the QT interval and ECG monitoring is necessary. Neuroleptics that can cause ventricular tachycardia of the “pirouette” type: Some phenothiazine neuroleptics (chlorpromazine, cyamemazine, levomepromazine, thioridazine, trifluoperazine), benzamides (amisulpride, sulpiride, tiapride, veralipride), butyrophenones (droperidol, haloperidol), other neuroleptics (pimozide). The risk of ventricular rhythm disturbances increases. (tachycardia of the “pirouette” type).MethadoneThe risk of ventricular rhythm disturbances (tachycardia of the “pirouette” type increases). Recommended: ECG and clinical observation. Combinations requiring precautions when using Amiodarone with: Oral anticoagulants: Increased anticoagulant effect and risk of bleeding, due to increased plasma concentrations of anticoagulants. The need for more frequent monitoring of the level of prothrombin in the blood and MHO (INR), as well as adaptation of doses of anticoagulants during treatment with amiodarone and after discontinuation of the drug. Beta blockers, with the exception of sotalol (a contraindicated combination) and esmolol (a combination that requires caution in use) Violations contractility, automaticity and conductivity (suppression of compensatory sympathetic mechanisms). Clinical and ECG monitoring. Beta blockers prescribed for heart failure (bisoprolol, carvedilol, metoprolol) Contractility and conduction disorders (synergistic effect) with the risk of developing severe bradycardia. Increased risk of ventricular arrhythmias, especially tachycardia of the “pirouette” type. Regular clinical and electrocardiographic monitoring is required. Cardiac glycosides Impairments of automaticity (excessive bradycardia) and atrioventricular conduction (synergism of action). When using digoxin, an increase in its concentration in plasma (due to decreased clearance of the alkaloid). It is necessary to carry out clinical and ECG monitoring, as well as determine the level of digoxin in plasma); It may be necessary to change the dose of digoxin. Oral diltiazem Risk of bradycardia and atrioventricular block, especially in the elderly. Clinical and ECG monitoring. Oral verapamil Risk of bradycardia and atrioventricular block, especially in the elderly. Clinical and ECG monitoring. Esmolol Disorders of contractility, automaticity and conduction (suppression of compensatory sympathetic mechanisms). Clinical and ECG monitoring. Hypokalemic drugs: potassium-sparing diuretics (in monotherapy or combination), stimulant laxatives, amphotericin B (iv), glucocorticoids (systemic), tetracosactide. Increases the risk of ventricular rhythm disturbances, especially tachycardia of the “pirouette” type "(hypokalemia is a predisposing factor). Clinical and ECG monitoring, laboratory tests. Lidocaine Risk of increased plasma concentrations of lidocaine, with the possibility of neurological and cardiac side effects, due to amiodarone's reduction in the metabolism of lidocaine in the liver. Clinical and ECG monitoring, if necessary, dose adjustment of lidocaine during treatment with amiodarone and after its discontinuation. Orlistat Risk of decreased plasma concentrations of amiodarone and its active metabolite. Clinical and, if necessary, ECG monitoring, Phenytoin (and, by extrapolation, fosphenytoin) Increased plasma levels of phenytoin with symptoms of overdose, especially of a neurological nature (decreased metabolism of phenytoin in the liver). Clinical monitoring and determination of plasma phenytoin levels; if possible, reduce the dose of phenytoin. Simvastatin Increased risk of side effects (depending on dose) such as rhabdomyolysis (decreased metabolism of simvastatin in the liver). The dose of simvastatin should not exceed 20 mg per day. If a therapeutic effect cannot be achieved at this dose, you should switch to another statin that does not interact with this type of interaction. Tacrolimus An increase in the level of tacrolimus in the blood due to inhibition of its metabolism by amiodarone. Blood levels of tacrolimus should be measured, renal function monitored, and tacrolimus levels leveled off. Drugs that cause bradycardia: Many drugs can cause bradycardia. This is especially true for class Ia antiarrhythmic drugs, beta blockers, some class III antiarrhythmic drugs, some calcium channel blockers, digitalis, pilocarpine and anticholinesterase agents. Risk of excessive bradycardia (cumulative effect). Combinations to consider Drugs that cause bradycardia: calcium channel blockers with bradycardic effect (verapamil), beta blockers (except sotalol), clonidine, guanfacine, digitalis alkaloids, mefloquine, cholinesterase inhibitors (donezepil, galantamine, rivastigmine, tacrine, ambemonium, pyridostigmine, neostigmine), pilocarpine. Risk of excessive bradycardia (cumulative effects). Incompatibilities When using PVC material or medical equipment plasticized with 2-diethylhexyl phthalate (DEHP) in the presence of amiodarone injection solution, DEHP may be released. To minimize exposure to DEHP, it is recommended that the solution be final diluted before infusion in DEHP-free equipment.
VERO-AMIODARONE
special instructions
Except in urgent cases, intravenous administration of amiodarone should be carried out only in the intensive care unit with constant monitoring of the ECG (due to the possibility of developing bradycardia and proarrhythmogenic effects) and lowering blood pressure.
The injectable form of amiodarone should be administered only as an infusion (except in cases of cardiac resuscitation due to cardiac arrest caused by ventricular fibrillation resistant to cardioversion (see "Dosage and Administration"), since even a very slow intravenous bolus may cause an excessive decrease in blood pressure, heart failure or severe respiratory failure.
In order to avoid reactions at the injection site (see “Side Effects”), the injectable form of amiodarone is recommended to be administered through a central venous catheter. Only in the case of cardiac resuscitation for cardiac arrest caused by ventricular fibrillation refractory to cardioversion, in the absence of central venous access (no central venous catheter in place), the injectable form of amiodarone can be administered into a large peripheral vein with maximum blood flow.
If treatment with amiodarone must be continued after cardiac resuscitation, the drug should be administered intravenously through a central venous catheter under constant monitoring of blood pressure and ECG.
Amiodarone should not be mixed in the same syringe or dropper with other medications.
Due to the possibility of the development of interstitial pneumonitis when severe shortness of breath or a dry cough appears after the administration of amiodarone, both accompanied and not accompanied by a deterioration in the general condition (increased fatigue, fever), it is necessary to perform a chest x-ray and, if necessary, discontinue the drug, since interstitial pneumonitis can lead to the development of pulmonary fibrosis. However, these phenomena are generally reversible with early discontinuation of amiodarone with or without the administration of glucocorticosteroids. Clinical manifestations usually disappear within 3-4 weeks. Recovery of the X-ray picture and lung function occurs more slowly (several months).
Following mechanical ventilation (eg, surgery) in patients receiving amiodarone, rare cases of acute respiratory distress syndrome, sometimes fatal, have been reported (possible interaction with high doses of oxygen). Therefore, it is recommended to strictly monitor the condition of such patients.
In patients receiving long-term treatment with amiodarone for cardiac arrhythmias, an increase in the incidence of ventricular fibrillation and/or an increase in the sensitivity threshold of the pacemaker or implanted artificial pacemaker has been reported, which may reduce their effectiveness. Therefore, before starting and during treatment with amiodarone, their correct functioning should be regularly monitored.
Due to the prolongation of the period of repolarization of the ventricles of the heart, the pharmacological effect of amiodarone causes certain changes in the ECG: prolongation of the QT interval, QTc (corrected), and the possible appearance of U waves. Allowable QT prolongation is no more than 450 ms or no more than 25% of the original value. These changes are not a manifestation of the toxic effect of the drug, but require monitoring to adjust the dose and assess the possible proarrhythmogenic effect. If II-III degree AV block, sinoatrial block or double-bundle intraventricular block develops, treatment with amodarone should be discontinued. If 1st degree AV block occurs, it is necessary to intensify monitoring of the patient.
If visual impairment occurs (blurred visual perception, decreased visual acuity), it is necessary to conduct a full ophthalmological examination, including fundus examination. If optic neuropathy or optic neuritis develops, treatment with amiodarone is discontinued due to the risk of blindness.
During the first 24 hours after starting use of the injectable form of amiodarone, severe acute liver damage may develop with the development of liver failure, sometimes with death. Regular monitoring of liver function is recommended before starting amiodarone use and regularly during amiodarone treatment. If the activity of “liver” transaminases increases, 3 times higher than the upper limit of normal, the dose of amiodarone should be reduced or discontinued.
General anesthesia. Before surgery, the anesthesiologist should be informed that the patient is receiving amiodarone. Treatment with amiodarone may increase the hemodynamic risk inherent in local or general anesthesia. This particularly applies to its bradycardic and hypotensive effects, decreased cardiac output and conduction disturbances.
Combinations with β-blockers other than sotalol (a contraindicated combination) and esmolol (a combination requiring special caution when used), verapamil and diltiazem can only be considered in the context of the prevention of life-threatening ventricular arrhythmias and in the case of restoration of cardiac activity in cardiac arrest caused by ventricular fibrillation resistant to cardioversion.
Electrolyte imbalances, especially hypokalemia: It is important to consider situations that may be accompanied by hypokalemia as predisposing to proarrhythmic effects. Hypokalemia should be corrected before starting amiodarone.
Side effects of the drug (see "Side Effects") are usually dose dependent; Therefore, care should be taken when determining the minimum effective maintenance dose to avoid or minimize the occurrence of adverse effects.
Amiodarone may cause thyroid dysfunction, especially in patients with a personal or family history of thyroid dysfunction. Therefore, in case of switching to oral amiodarone during treatment and several months after the end of treatment, careful clinical and laboratory monitoring should be carried out. If thyroid dysfunction is suspected, the concentrations of T3, T4 and TSH in the blood serum should be determined.
Clinical manifestations are usually mild, so symptoms such as weight loss, the occurrence of rhythm disturbances, angina attacks, and the development of CHF should alert the doctor. The diagnosis is confirmed by identifying a decrease in the concentration of thyroid-stimulating hormone (TSH) in the blood serum, determined using an ultrasensitive TSH test. In this case, amiodarone should be discontinued. Recovery usually occurs within a few months after treatment is stopped. First, clinical manifestations disappear, then normalization of thyroid function indicators occurs. Severe cases of thyrotoxicosis, which can sometimes be fatal (both due to the thyrotoxicosis itself and due to a dangerous imbalance between myocardial oxygen demand and oxygen supply), require emergency treatment. Treatment should be selected individually in each specific case: antithyroid drugs (which may not always be effective), glucocorticosteroids, beta-blockers.
Possible suppression of bone marrow function, manifested by the development of normocytic normochromic anemia, thrombocytopenia or neutropenia, possible formation of granulomas, in addition, in post-registration studies or observations, cases of the development of agranulocytosis, hemolytic anemia, pancytopenia were identified. Symptoms may regress after discontinuation of the drug and the prescription of glucocorticosteroids; if the drug is re-prescribed, they may recur.
While taking amiodarone, the development of undesirable mental phenomena is possible, including changes in consciousness, hallucinations and delirium. The developed condition may be resistant to the use of benzodiazepine drugs; discontinuation of amiodarone is necessary.
The use of amiodarone can cause the development of unpleasant skin phenomena, the most commonly reported development of increased photosensitivity and changes in skin tone (more often in patients under 60 years of age), less often - reversible alopecia.
Severe adverse events may develop, including toxic epidermal necrolysis, exfoliative dermatitis, bullous dermatosis, cutaneous vasculitis, linear IgA-dependent dermatosis, psoriasis, skin cancer, pruritus.
Patients should be instructed about the possibility of photosensitivity reactions, the need to avoid exposure to sunlight and use sunscreen if necessary. Increased sensitivity to sunlight may persist for several months after stopping amiodarone. In most cases, manifestations are limited to sensations of redness, burning or "twitching" of the skin exposed to intense sunlight, but severe phototoxic reactions can develop. Hypersensitivity reactions associated with the use of the drug include the cutaneous reactions listed above, as well as anaphylactic and anaphylactoid reactions, including shock, angioedema, lupus erythematosus, drug reaction with eosinophilia and systemic symptoms. It is possible to develop cross-allergic reactions to amiodarone in patients with hypersensitivity to iodine-containing contrast agents.
The safety and effectiveness of amiodarone have not been studied in children. Vero-amiodarone injection contains benzyl alcohol. Cases of severe choking with fatal outcome have been reported in newborns after intravenous administration of solutions containing benzyl alcohol.
Instructions for use AMIODARONE
Medicines that can cause torsades de pointes are primarily class Ia and class III antiarrhythmic drugs and some antipsychotics. Hypokalemia is a predisposing factor, as is bradycardia or congenital or acquired prolongation of the QT interval.
Combinations with
- Drugs that can cause ventricular tachycardia of the “pirouette” type.
- Class Ia antiarrhythmic drugs (quinidine, hydroquinidine, isopyramide).
- Class III antiarrhythmic drugs (dofetilide, ibutilide, sotalol).
- Other drugs, such as bepridil, cisapride, difemanil, IV ritromycin, mizolastine, IV vincamine, moxifloxacin, IV spiramycin.
- Sultopride.
The risk of ventricular rhythm disturbances (pirouette-type tachycardia) increases.
These contraindications do not apply to the use of amiodarone for cardiopulmonary resuscitation in cardiac arrest refractory to electrical defibrillation.
Not recommended combinations with
Cyclosporine
There may be an increase in the level of cyclosporine in plasma, associated with a decrease in the metabolism of the drug in the liver, with possible nephrotoxic manifestations.
Determination of the level of cyclosporine in the blood, checking renal function and reviewing the dosage during treatment with amiodarone and after discontinuation of the drug.
Diltiazem for injection
Risk of bradycardia and atrioventricular block. If a combination is unavoidable, strict clinical and continuous ECG monitoring should be established.
Verapamil for injection
Risk of bradycardia and atrioventricular block. If a combination is unavoidable, strict clinical and continuous ECG monitoring should be established.
Antiparasitic drugs that can cause torsade de pointes (halofantrine, pentamidine, lumefantrine)
If the combination is unavoidable, preliminary control of the QT interval and ECG monitoring is necessary.
Neuroleptics that can cause ventricular tachycardia of the “pirouette” type:
Some phenothiazine antipsychotics (chlorpromazine, cyamemazine, levomepromazine, thioridazine, trifluoperazine), benzamides (amisulpride, sulpiride, tiapride, veralipride), butyrophenones (droperidol, haloperidol), other antipsychotics (pimozide).
The risk of ventricular rhythm disturbances (pirouette-type tachycardia) increases.
Methadone
The risk of ventricular rhythm disturbances (pirouette-type tachycardia) increases. Recommended:
- ECG and clinical observation.
Combinations requiring precautions when using Amiodarone with:
Oral anticoagulants:
Increased anticoagulation effect and risk of bleeding, due to increased concentrations of anticoagulants in plasma. The need for more frequent monitoring of the level of prothrombin in the blood and MHO (INR), as well as adaptation of doses of anticoagulants during treatment with amiodarone and after discontinuation of the drug.
Beta blockers, with the exception of sotalol (contraindicated combination) and esmolol (combination requiring caution when used)
Violations of contractility, automatism and conduction (suppression of compensatory sympathetic mechanisms). Clinical and ECG monitoring.
Beta blockers prescribed for heart failure (bisoprolol, carvedilol, metoprolol)
Impaired contractility and conduction (synergistic effect) with the risk of developing severe bradycardia. Increased risk of ventricular arrhythmias, especially torsade de pointes.
Regular clinical and electrocardiographic monitoring is necessary.
Cardiac glycosides
Disorders of automaticity (excessive bradycardia) and atrioventricular conduction (synergism of action). When using digoxin, its concentration in plasma increases (due to decreased clearance of the alkaloid).
It is necessary to carry out clinical and ECG monitoring, as well as determination of plasma digoxin levels); It may be necessary to change the dose of digoxin.
Diltiazem for oral administration
Risk of bradycardia and atrioventricular block, especially in the elderly. Clinical and ECG control.
Verapamil for oral administration
Risk of bradycardia and atrioventricular block, especially in the elderly. Clinical and ECG control.
Essex scraper
Violations of contractility, automatism and conduction (suppression of compensatory sympathetic mechanisms). Clinical and ECG monitoring.
Hypokalemic drugs: potassium-sparing diuretics (in monotherapy or combination), stimulant laxatives, amphotericin B (iv), glucocorticoids (systemic), tetracosactide.
The risk of ventricular rhythm disturbances increases, especially tachycardia of the “pirouette” type (hypokalemia is a predisposing factor). Clinical and ECG monitoring, laboratory tests.
Lidocaine
Risk of increased lidocaine plasma concentrations, with the possibility of neurological and cardiac side effects, due to amiodarone's decreased metabolism of lidocaine in the liver. Clinical and ECG monitoring, if necessary, dose adjustment of lidocaine during treatment with amiodarone and after its discontinuation.
Orlistat
Risk of decreased plasma concentrations of amiodarone and its active metabolite. Clinical and, if necessary, ECG monitoring.
Phenytoin (and, by extrapolation, fosphenytoin)
An increase in the level of phenytoin in plasma with symptoms of overdose, especially of a neurological nature (decreased metabolism of phenytoin in the liver). Clinical monitoring and determination of plasma phenytoin levels; if possible, reduce the dose of phenytoin.
Simvastatin
Increased risk of side effects (depending on dose) such as rhabdomyolysis (decreased metabolism of simvastatin in the liver). The dose of simvastatin should not exceed 20 mg/day.
If a therapeutic effect is not achieved at this dose, you should switch to another statin that does not interact with this type of interaction.
Tacrolimus
An increase in the level of tacrolimus in the blood due to inhibition of its metabolism by amiodarone. Measurement of tacrolimus blood levels, monitoring of kidney function and leveling of tacrolimus levels should be carried out.
Drugs that cause bradycardia:
Many drugs can cause bradycardia. This is especially true for class 1a antiarrhythmic drugs, beta blockers, some class III antiarrhythmic drugs, some calcium channel blockers, digitalis, pilocarpine and anticholinesterase agents.
Risk of excessive bradycardia (cumulative effect).
Combinations to Consider
Drugs that cause bradycardia:
- calcium channel blockers with bradycardic effect (verapamil), beta blockers (except sotalol), clonidine, guanfacine, digitalis alkaloids, mefloquine, cholinesterase inhibitors (donezepil, galantamine, rivastigmine, tacrine, ambemonium, pyridostigmine, neostigmine), pilocarpine.
Risk of excessive bradycardia (cumulative effects).
Incompatibilities
When PVC material or medical equipment plasticized with 2-diethylhexyl phthalate (DEHP) is used in the presence of amiodarone injection solution, DEHP may be released. To minimize exposure to DEHP, it is recommended that the solution be final diluted before infusion in DEHP-free equipment.
The role of amiodarone in the treatment of arrhythmias
Amiodarone is undoubtedly the most effective antiarrhythmic drug (AAD) available. It is even called an “arrhythmolytic drug.” Although amiodarone was synthesized in 1960, and reports of its antiarrhythmic activity first appeared in 1969, to date, none of the new AAPs can compare with it in effectiveness. Amiodarone accounts for about 25% of the total number of prescriptions for all AAPs.
Amiodarone has the properties of all four classes of AAP and, in addition, has a moderate α-blocking and antioxidant effect. However, the main antiarrhythmic property of amiodarone is the prolongation of the action potential and the effective refractory period of all parts of the heart.
However, the attitude of cardiologists towards amiodarone from the very beginning of its use for the treatment of arrhythmias was very contradictory. Due to the large list of extracardiac side effects, amiodarone, despite the fact that its high antiarrhythmic effectiveness was already known, was considered a reserve drug for quite a long time: it was recommended to use it only for life-threatening arrhythmias and only in the absence of effect from all other AAPs. The drug has gained a “reputation” as a “last resort”, used “only for the treatment of life-threatening diseases (LN Horowitz, J. Morganroth, 1978; JW Mason, 1987; JC Somberg, 1987).
After a number of studies, including CAST, it was revealed that while taking class I AAP, mortality in patients with organic heart disease can increase more than 3 times; It turned out that amiodarone is not only the most effective, but also the safest (after β-blockers) AAP. Numerous large controlled studies of the effectiveness and safety of amiodarone not only did not reveal an increase in overall mortality; on the contrary, a decrease in this indicator and the frequency of arrhythmic and sudden death was found. The incidence of arrhythmogenic effects, in particular torsade de pointes (TdP), while taking amiodarone is less than 1%, which is much lower than when taking other AAPs that prolong the QT interval. For comparison: the arrhythmogenic effect of sotalol hydrochloride in patients with ventricular arrhythmias is 4–5%, and the arrhythmogenic effect of foreign class I drugs reaches 20% or more. Thus, amiodarone has become the drug of first choice in the treatment of arrhythmias. Amiodarone is the only AAP, the use of which, according to renowned cardiologists, is considered the safest for outpatient treatment, even in patients with organic heart disease. The arrhythmogenic effect of amiodarone is rarely observed, and this does not allow us to identify a reliable connection between the occurrence of arrhythmogenic effects and the presence of organic heart damage (EM Prystovsky, 1994, 2003; LA Siddoway, 2003).
It should be emphasized that amiodarone is the only drug whose use is safe in heart failure. For any arrhythmias requiring treatment in patients with heart failure, amiodarone is primarily indicated. Moreover, in acute heart failure or decompensation of chronic heart failure with a high heart rate (sinus tachycardia or tachysystole in atrial fibrillation), when the use of β-blockers is contraindicated, and the administration of digoxin is ineffective and leads to dangerous consequences, a decrease in heart rate, improvement of hemodynamics and the patient's condition can be achieved with the help of amiodarone.
Side effects of amiodarone
As already noted, the main disadvantage of amiodarone is the likelihood of developing many extracardiac side effects, which, with long-term use of the drug, are observed in 10–52% of patients. However, the need to discontinue amiodarone occurs in 5–25% of patients (JA Johus et al., 1984; JF Best et al., 1986; WM Smith et al., 1986). The main side effects of amiodarone include: photosensitivity, skin discoloration, thyroid dysfunction (both hypothyroidism and hyperthyroidism), increased transaminase activity, peripheral neuropathies, muscle weakness, tremor, ataxia, visual impairment. Almost all of these side effects are reversible and disappear after discontinuation or reduction of the dose of amiodarone.
Thyroid dysfunction is observed in 10% of cases. In this case, subclinical hypothyroidism is much more common. Hypothyroidism can be controlled by taking levothyroxine. In case of hyperthyroidism, discontinuation of amiodarone is required (except for life-threatening arrhythmias) and treatment of hyperthyroidism (I. Klein, F. Ojamaa, 2001).
The most dangerous side effect of amiodarone is lung damage, causing interstitial pneumonitis or, less commonly, pulmonary fibrosis. According to various authors, the incidence of lung damage ranges from 1 to 17% (JJ Heger et al., 1981; B. Clarke et al., 1985, 1986). However, these data were obtained in the 1970s, when amiodarone was prescribed for a long time and in large doses. In most patients, lung damage develops only with long-term use of relatively large maintenance doses of amiodarone - more than 400 mg/day (up to 600 or even 1200 mg/day). In Russia, such doses are used extremely rarely; usually the maintenance daily dose is 200 mg (5 days a week) or even less. Currently, the incidence of “amiodarone-induced lung injury” is no more than 1% per year. In one study, the incidence of lung injury was no different between amiodarone and placebo (SJ Connolly, 1999; MD Siddoway, 2003). Clinical manifestations of “amiodarone lung damage” resemble an acute infectious lung disease: the most common complaint is shortness of breath, while a slight increase in temperature, cough, and weakness are observed. Radiologically, diffuse interstitial infiltration of the lung tissue is noted; localized changes can be observed, including the so-called “air-containing opacities” (JJ Kennedy et al., 1987). Treatment for amiodarone-induced lung injury involves discontinuation of amiodarone and administration of corticosteroids.
Basic amiodarone therapy regimens
It is necessary to dwell separately on some features of the use of amiodarone. For the antiarrhythmic effect of amiodarone to occur, a period of “saturation” is required.
Taking amiodarone orally. In Russia, the most common regimen for prescribing amiodarone is 600 mg/day (3 tablets per day) for 1 week, then 400 mg/day (2 tablets per day) for another 1 week, maintenance dose - 200 mg for a long time per day (1 tablet per day) or less. A faster effect can be achieved by prescribing the drug at a dose of 1200 mg/day for 1 week (6 tablets per day), then gradually reducing the dose to 200 mg per day or less. One of the regimens recommended in the international guidelines for cardiology Heart Disease (2001): taking amiodarone for 1–3 weeks at 800–1600 mg/day (i.e. 4–8 tablets per day), then taking 800 mg (4 tablets) for 2-4 weeks, after that - 600 mg / day (3 tablets) for 1-3 months and then switch to maintenance doses - 300 mg / day or less (titration depending on sensitivity patient to minimum effective doses).
There are reports of the effective use of high loading doses of amiodarone - 800-2000 mg 3 times a day (i.e. up to 6000 mg / day - up to 30 tablets per day) in patients with severe, life-threatening, refractory to other treatment methods ventricular arrhythmias with repeated episodes of ventricular fibrillation (ND Mostow et al., 1984; SJL Evans et al., 1992). A single dose of amiodarone at a dose of 30 mg/kg body weight is officially recommended as one of the ways to restore sinus rhythm in atrial fibrillation.
Thus, the use of large loading doses of amiodarone is relatively safe and effective. To achieve an antiarrhythmic effect, it is not necessary to achieve a stable concentration of the drug in the body. Short-term administration of large doses may be even safer than long-term administration of the drug at lower daily doses, and allows for rapid assessment of the antiarrhythmic effectiveness of the drug (LE Rosenfeld, 1987). During the “saturation” period, it can be recommended to take amiodarone at a dose of 1200 mg/day during the first week. After achieving the antiarrhythmic effect, the dose is gradually reduced to the minimum effective. It has been shown that effective maintenance doses of amiodarone can be 100 mg/day and even 50 mg/day (A. Gosselink, 1992; M. Dayer, S. Hardman, 2002).
Intravenous administration of amiodarone. The effectiveness of intravenous amiodarone has been less studied. When administered as a bolus intravenously, amiodarone is usually prescribed at a dose of 5 mg/kg body weight over 5 minutes. In recent years, slower intravenous administration of amiodarone has been recommended. With rapid administration, a decrease in the effectiveness of the drug may occur due to vasodilation, lowering blood pressure and activation of the sympathetic nervous system. One of the most popular intravenous amiodarone administration regimens is a bolus of 150 mg over 10 minutes, then an infusion at a rate of 1 mg/min for 6 hours (360 mg over 6 hours), followed by an infusion at a rate of 0.5 mg/min. However, there is evidence of safe and effective intravenous administration of amiodarone at a dose of 5 mg/kg body weight over 1 min or even 30 s (R. Hofmann, G. Wimmer, F. Leisch, 2000; DE Hilleman et al., 2002). The antiarrhythmic effect of amiodarone begins to appear within 20–30 minutes. Side effects with intravenous administration are rare and usually have no symptoms. 5% of patients have bradycardia, 16% have a decrease in blood pressure (LE Siddoway, 2003).
Interestingly, intravenous administration of amiodarone in its effect on electrophysiological parameters differs sharply from taking a loading dose of the drug orally. When conducting an electrophysiological study after intravenous administration, only a slowdown in conduction through the AV node (an increase in the AH interval) and an increase in the refractory period of the AV node are noted. Thus, with intravenous administration of amiodarone, only an antiadrenergic effect occurs (no class III effect), while after taking a loading dose of amiodarone orally, in addition to slowing conduction through the AV node, there is an increase in the duration of the QT interval and effective refractory periods in all parts of the heart (atria, AV node, His–Purkinje system, ventricles and accessory pathways). Based on these data, the effectiveness of intravenous amiodarone for atrial and ventricular arrhythmias is difficult to explain (HJJ Wellens et al., 1984; RN Fogoros, 1997).
Amiodarone is administered intravenously into the central veins through a catheter, since long-term administration into peripheral veins may cause phlebitis. When injecting the drug into peripheral veins, 20 ml of saline must be quickly injected immediately after the injection.
Published data suggest that intravenous amiodarone is more effective for ventricular tachyarrhythmias than lidocaine, bretylium tosylate, and procainamide.
Principles for selecting effective antiarrhythmic therapy
In the absence of contraindications, amiodarone is the drug of choice for almost all arrhythmias requiring antiarrhythmic therapy. The use of amiodarone is advisable for all types of supraventricular and ventricular arrhythmias. The effectiveness of AAP in the treatment of the main clinical forms of rhythm disturbances is approximately the same: in the treatment of extrasystole in most of them it is 50–75%, in therapy to prevent the recurrence of supraventricular tachyarrhythmias - from 25 to 60%, in severe ventricular tachycardias - from 10 to 40 %. Moreover, one drug is more effective in some patients, and the other in others. An exception is amiodarone - its effectiveness often reaches 70–80% even with arrhythmias refractory to other AAPs in this group of patients.
In patients with arrhythmias, but without signs of organic heart disease, the prescription of any AAP is considered acceptable. In patients with organic heart disease (post-infarction cardiosclerosis, ventricular hypertrophy and/or cardiac dilatation), the first choice drugs are amiodarone and beta-blockers. Numerous studies have found that the use of class I AAP in patients with organic heart disease is accompanied by a significant increase in mortality. Thus, amiodarone and β-blockers are not just the drugs of choice in patients with organic heart disease, but practically the only means for the treatment of arrhythmias.
Taking into account the safety of AAPs, it is advisable to begin assessing their effectiveness with β-blockers or amiodarone. If monotherapy is ineffective, the effectiveness of a combination of amiodarone and β-blockers is assessed. If there is no bradycardia or prolongation of the PR interval, any β-blocker can be combined with amiodarone.
In patients with bradycardia, pindolol (Wisken) is added to amiodarone. Coadministration of amiodarone and beta-blockers has been shown to significantly reduce mortality in patients with cardiovascular disease than either drug alone. Some experts even recommend implantation of a dual-chamber stimulator (in DDD mode) for safe amiodarone therapy in combination with beta-blockers. Only if there is no effect from β-blockers and/or amiodarone, class I AAPs are used. In this case, class I drugs are usually prescribed while taking a β-blocker or amiodarone. The CAST study showed that co-administration of β-blockers eliminated the negative effect of class I anti-inflammatory drugs on survival of patients with arrhythmias. In addition to class I drugs, it is possible to prescribe sotalol hydrochloride (a β-blocker with the properties of a class III drug).
Combinations of amiodarone and other AAPs
If there is no effect from monotherapy, combinations of amiodarone are prescribed not only with β-blockers, but also with other AAPs. Theoretically, of course, the most rational is considered to be a combination of drugs with different mechanisms of antiarrhythmic action. For example, it is advisable to combine amiodarone with class I drugs: propafenone, lappaconitine hydrobromide, etacizine. Class Ic drugs do not prolong the QT interval. The simultaneous administration of drugs that have the same effect on the electrophysiological properties of the myocardium seems dangerous. For example, amiodarone and sotalol hydrochloride prolong the QT interval, and the risk of QT prolongation and associated torsade de pointes (TdP) is considered to be increased when these drugs are taken concomitantly. However, in combination therapy with AAPs, they are prescribed in reduced doses. Therefore, we can expect both a lack of influence of combination therapy on the frequency of arrhythmogenic effects and a reduction in the frequency of undesirable effects. Of interest in this regard are the results of one study in which ibutilide (a drug that prolongs the QT interval, the incidence of torsade de pointes (TdP) reaches 8%) was administered to patients with recurrent atrial fibrillation who were chronically taking amiodarone. Restoration of sinus rhythm was achieved in 54% with atrial flutter and in 39% with atrial fibrillation. At the same time, in 70 patients, only one case of tachycardia of the “pirouette” type was noted (1.4%). It should be noted that in this study, ibutilide was not discontinued if QT prolongation or bradycardia occurred (K. Glatter et al., 2001). Thus, amiodarone may even reduce the risk of torsade de pointes (TdP) when combined with class III drugs. In this case, reports of cases of stopping tachycardia of the “pirouette” type with amiodarone, including in patients with congenital variants of QT interval prolongation, are explained. In addition, prolongation of the QT interval by 15% or more is one of the predictors of the effectiveness of amiodarone during long-term use.
An approximate sequence for selecting AAT for recurrent arrhythmias in patients with organic heart disease can be presented as follows:
- β-blocker or amiodarone;
- β-blocker + amiodarone;
- sotalol hydrochloride;
- amiodarone + AAP Ic (Ib) class;
- β-blocker + any class I drug;
- amiodarone + β-blocker + class Ic (Ib) AAP;
- sotalol hydrochloride + AAP Ic (Ib) class.
The use of amiodarone in certain clinical forms of arrhythmias
Since amiodarone is the most effective drug for almost all types of cardiac arrhythmias, and especially if it is necessary to prevent recurrent arrhythmias, the selection scheme for anti-relapse AAT is applicable for all recurrent arrhythmias, ranging from extrasystole to life-threatening ventricular tachyarrhythmias, up to “electrical storm” .
Atrial fibrillation. Currently, due to its high effectiveness, good tolerability and ease of administration, restoration of sinus rhythm in atrial fibrillation using a single oral dose of amiodarone is becoming increasingly important. The recommended dose for a single dose of the drug is 30 mg/kg body weight. The average time to restore sinus rhythm after taking this dose is about 6 hours.
GE Kochiadakis et al (1999) compared two schemes for the use of amiodarone to restore sinus rhythm during atrial fibrillation: 1) on the first day - oral administration of 2 g of amiodarone (500 mg 4 times a day), on the second day - 800 mg (200 mg each). mg 4 times a day); 2) intravenous drip administration of amiodarone: 300 mg over 1 hour, then - 20 mg/kg during the first day, second day - 50 mg/kg.
Restoration of sinus rhythm was noted in 89% of patients taking amiodarone orally (first regimen), in 88% with intravenous infusion of amiodarone (second regimen), and in 60% with placebo. With intravenous administration, several cases of decreased blood pressure and the occurrence of thrombophlebitis were observed. Taking amiodarone orally did not cause any side effects.
At the Department of Therapy of the Russian State Medical University, the effectiveness of a single oral dose of amiodarone (cordarone) at a dose of 30 mg/kg body weight for atrial fibrillation was studied. Restoration of sinus rhythm was achieved in 80% of patients. However, no significant side effects were noted (Dzhanashiya et al., 1995, 1998; Khamitsaeva et al., 2002).
Amiodarone is the most effective drug for preventing recurrence of atrial fibrillation. In a direct comparison with sotalol hydrochloride and propafenone, amiodarone was found to be 1.5 to 2 times more effective than sotalol hydrochloride and propafenone (CTAF and AFFIRM studies).
There are reports of very high effectiveness of amiodarone even when prescribed to patients with severe heart failure (NYHA classes III, IV): out of 14 patients, sinus rhythm was maintained for 3 years in 13 patients (93%), and out of 25 patients - in 21 (84%) within 1 year (AT Gosselink et al., 1992; HR Middlekauff et al., 1993).
Ventricular tachycardia. To stop ventricular tachycardia, it is recommended to use: amiodarone - 300-450 mg intravenously, lidocaine - 100 mg intravenously, sotalol hydrochloride - 100 mg intravenously, procainamide - 1 g intravenously. After restoration of sinus rhythm, if necessary, infusion of an effective AAP is performed.
The intervals between administration of each drug depend on the clinical situation. In case of severe hemodynamic disturbances, electrical cardioversion is performed at any stage. True, the authors of international recommendations for cardiopulmonary resuscitation and emergency cardiology (2000) do not recommend administering more than one drug, and if there is no effect from the first drug, they consider it advisable to immediately use electrical cardioversion.
The clinical effectiveness of amiodarone in preventing recurrence of ventricular tachyarrhythmias ranges from 39 to 78% (average 51%) (HL Greene et al., 1989; Golitsyn et al., 2001).
To characterize a particularly severe course of ventricular tachyarrhythmias, some “jargon” definitions are sometimes used, for example, “electrical storm” - recurrent unstable polymorphic ventricular tachycardia and/or ventricular fibrillation. Quantitative definitions, according to various authors, range from “more than 2 episodes in 24 hours” to “19 episodes in 24 hours or more than 3 episodes in 1 hour” (K. Nademanee et al., 2000). Patients with an “electrical storm” undergo repeated defibrillation. One of the most effective ways to overcome this severe complication is to prescribe β-blockers in combination with intravenous administration and oral administration of large doses of amiodarone (up to 2 g or more per day). There are reports of success using very large doses of amiodarone. For severe, refractory to drug therapy (ineffectiveness of lidocaine, bretylium tosylate, procainamide and other AAPs) and life-threatening recurrent ventricular tachyarrhythmias), amiodarone was successfully prescribed orally up to 4–6 g per day (50 mg/kg) for 3 days (i.e. . 20–30 tablets), then 2–3 g per day (30 mg/kg) for 2 days (10–15 tablets), followed by a dose reduction (SJL Evans et al., 1992). If patients with electrical storm respond to intravenous amiodarone and continue to receive oral amiodarone, the survival rate for these patients is 80% within the first year (RJ Fogel, 2000). When comparing the effectiveness of amiodarone and lidocaine in patients with ventricular tachycardia refractory to electrical cardioversion and defibrillation, amiodarone was significantly more effective in increasing the survival of such patients (P. Dorian et al., 2002).
The second term used to denote the severe course of tachycardia is the term incessant (“continuous”, “persistent”, “difficult to cure”, “unceasing”) - continuously recurrent monomorphic ventricular tachycardia of severe course. In this variant of the course of ventricular tachycardia, combinations of AAP are used, for example, amiodarone in combination with lidocaine, mexiletine or class Ia and Ic antiarrhythmics. There are reports of the effectiveness of blockade of the left stellate ganglion. There is also evidence of the high effectiveness of intra-aortic balloon counterpulsation. With this procedure, complete cessation of recurrent tachycardia is achieved in 50% of patients, and a noticeable improvement in tachycardia control is achieved in 86% (EC Hanson et al., 1980; H. Bolooki, 1998; JJ Germano et al., 2002).
Increased risk of sudden death. For a long period of time, the main method of treatment for patients at increased risk of sudden death was the use of AAP. The most effective way to select antiarrhythmic therapy was to assess its effectiveness using intracardiac electrophysiological studies and/or repeated 24-hour ECG monitoring before and after AAP administration.
In the CASCADE study, empirical amiodarone was also found to be much more effective in patients who had suffered sudden death than class I drugs (quinidine, procainamide, flecainide) selected using repeated electrophysiological studies and ECG monitoring (41% and 20%, respectively) .
It has been established that to prevent sudden death, it is most advisable to prescribe β-blockers and amiodarone.
In the CAMIAT study, the use of amiodarone in post-infarction patients was accompanied by a significant reduction in arrhythmic mortality by 48.5% and cardiovascular mortality by 27.4%. The EMIAT study noted a significant reduction in arrhythmic mortality by 35%. A meta-analysis of 13 studies of the effectiveness of amiodarone in post-infarction patients and patients with heart failure (ATMA) revealed a significant reduction in arrhythmic mortality by 29% and overall mortality by 13%.
The simultaneous administration of a β-blocker and amiodarone is even more effective. When taking a beta-blocker and amiodarone in patients who had myocardial infarction, there was an additional reduction in arrhythmic mortality by 2.2 times, cardiac mortality by 1.8 times and overall mortality by 1.4 times (EMIAT and CAMIAT studies). In some patient groups, amiodarone is as effective as implantable cardioverter defibrillators (ICDs) in reducing overall mortality.
ICD discharges are very painful (the pain experienced by a patient during an ICD discharge is usually compared to “a horse’s hoof hitting the chest”). Prescribing amiodarone to patients with ICD significantly reduces the frequency of defibrillator discharges by reducing the frequency of arrhythmias. The recent OPTIC study compared the effectiveness of beta-blockers, a combination of amiodarone and beta-blockers, and sotalol hydrochloride in reducing the incidence of ICD discharges. The combination of amiodarone and β-blockers was 3 times more effective than β-blockers alone and more than 2 times more effective than sotalol hydrochloride (SJ Connolly et al., 2006).
Thus, despite a number of disadvantages of the drug, amiodarone still represents the first choice AAP.
It should be noted that the use of generic forms of amiodarone is fraught with a lack of treatment effectiveness and the development of complications (JA Reiffel and PR Kowey, 2000). A study by S. G. Kanorsky and A. G. Staritsky revealed a 12-fold increase in the frequency of relapses of atrial fibrillation when replacing the original drug with generics.
In the US and Canada, approximately 20,000 hospitalizations could be avoided each year as a result of replacing amiodarone with generic versions (PT Pollak, 2001).
P. Kh. Janashia, Doctor of Medical Sciences, Professor N. M. Shevchenko, Doctor of Medical Sciences, Professor T. V. Ryzhova Russian State Medical University, Moscow
Amiodarone, 10 pcs., 3 ml, 50 mg/ml, concentrate for solution for intravenous administration
Intravenous bolus administration of the drug Amiodarone is usually not recommended due to hemodynamic risks (development of a pronounced decrease in blood pressure, vascular collapse); intravenous drip administration of the drug is preferable.
Intravenous jet administration of the drug Amiodarone should be carried out only in the intensive care unit with constant monitoring of ECG (due to the possibility of developing excessive bradycardia and arrhythmogenic effects) and blood pressure (due to the possibility of lowering blood pressure).
In order to avoid reactions at the injection site, it is recommended that Amiodarone be administered through a central venous catheter. Only in the case of cardiac resuscitation for cardiac arrest caused by ventricular fibrillation resistant to defibrillation, in the absence of central venous access (no central venous catheter in place), Amiodarone can be administered into a large peripheral vein with maximum blood flow. If it is necessary to continue treatment with Amiodarone after cardiac resuscitation, Amiodarone should be administered intravenously through a central venous catheter under constant monitoring of blood pressure and ECG.
Amiodarone should not be mixed in the same syringe or dropper with other medications. Do not administer other drugs into the same infusion line as Amiodarone.
Cardiac reactions
The occurrence of new rhythm disturbances or worsening of existing rhythm disturbances, sometimes with fatal outcome, has been reported. It is very important to make a differential diagnosis between the insufficient effectiveness of the drug and its arrhythmogenic effect, whether combined or not with an aggravation of the severity of cardiovascular pathology. Arrhythmogenic effects have been reported significantly less frequently with Amiodarone than with other antiarrhythmic drugs and have generally been observed in the presence of factors that prolong the QT interval, such as drug interactions and/or electrolyte disturbances. Despite the ability of Amiodarone to prolong the QT interval, it has shown low activity in provoking torsade de pointes (TdP).
Severe bradycardia.
When Amiodarone was used in combination with sofosbuvir in combination with other direct-acting antiviral drugs against viral hepatitis C, such as daclatasvir, simeprevir, ledipasvir, cases of severe, potentially life-threatening bradycardia, as well as heart block, were observed. Therefore, the simultaneous use of these drugs with Amiodarone is not recommended.
If concomitant use of these drugs with Amiodarone cannot be avoided, close monitoring of patients is recommended after initiating sofosbuvir in combination with other direct-acting antivirals. After starting concomitant use of sofosbuvir, patients who are at high risk of developing bradyarrhythmias should be monitored continuously in a hospital setting for at least 48 hours.
Due to the long half-life of amiodarone, appropriate monitoring should also be performed in patients who have stopped taking amiodarone within the last few months before starting treatment with sofosbuvir in combination with other direct acting antivirals.
Patients taking the above drugs against hepatitis C virus in combination with Amiodarone, either simultaneously with other drugs that slow the heart rate or without combination with such drugs, should be informed about symptoms indicating the development of bradycardia and heart block. If they occur, they should seek medical attention immediately.
Pulmonary disorders
The appearance of shortness of breath or dry cough may be associated with pulmonary toxicity, in particular the development of interstitial pneumonitis. In very rare cases, the development of interstitial pneumonitis has been observed after intravenous administration of the drug Amiodarone. If the development of interstitial pneumonitis is suspected in patients who experience severe shortness of breath, either isolated or in combination with a deterioration in general condition (fatigue, weight loss, fever), an X-ray examination of the lungs should be performed. The need for Amiodarone should be re-evaluated as interstitial pneumonitis is usually reversible if the drug is discontinued early (clinical symptoms usually resolve within 3-4 weeks, followed by a slower improvement in radiographic findings and pulmonary function over several months). Treatment with glucocorticosteroids should be considered.
In addition, in very rare cases, usually immediately after surgery, a serious respiratory complication (adult acute respiratory distress syndrome), sometimes fatal, has been observed in patients treated with amiodarone; the possibility of a connection between its development and interaction with high oxygen concentrations is assumed.
Liver disorders
Careful monitoring of liver function tests (monitoring the activity of liver transaminases) is recommended before starting the use of Amiodarone and regularly during treatment with the drug. During the first 24 hours after intravenous administration of Amiodarone, acute liver damage (including hepatocellular failure or liver failure, sometimes fatal) and chronic liver damage may occur. Therefore, if the activity of “liver” transaminases increases, 3 times higher than the upper limit of normal, the dose of Amiodarone should be reduced or discontinued.
Clinical and laboratory signs of chronic liver failure when using the drug Amiodarone orally can be minimally expressed (hepatomegaly, increased transaminase activity 5 times the upper limit of normal) and reversible after discontinuation of the drug, but cases of death have been reported.
Severe bullous reactions
Treatment with Amiodarone should be stopped immediately if symptoms and manifestations of life-threatening or even fatal reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis appear, namely the appearance of a progressive skin rash, often with blistering, or the appearance of damage to the mucous membranes.
Visual disorders
If decreased visual acuity or blurred vision occurs, a complete ophthalmological examination, including funduscopy (examination of the fundus of the eye), should be immediately performed. The manifestation of neuropathy and/or optic neuritis requires discontinuation of amiodarone due to the possible development of blindness.
Drug interactions
The simultaneous use of Amiodarone with the following drugs is not recommended: beta-blockers, blockers of “slow” calcium channels, slowing heart rate (verapamil, diltiazem), laxatives, stimulating intestinal motility, which can cause hypokalemia.
Hypokalemia
Hypokalemia should be corrected before starting Amiodarone.
Children
The safety and effectiveness of Amiodarone have not been studied in children. Amiodarone ampoules contain benzyl alcohol. Severe choking with fatal outcome has been reported in newborns after intravenous administration of solutions containing benzyl alcohol. Symptoms of the development of this complication are: acute development of suffocation, decreased blood pressure, bradycardia and collapse.
General and local anesthesia
Before surgery, the anesthesiologist should be informed that the patient has been administered the drug Amiodarone. Treatment with Amiodarone may increase the hemodynamic risk inherent in local or general anesthesia (in particular, slowing of heart rate, slowing of conduction and decreased contractility of the heart.)
Thyroid dysfunction
Amiodarone may cause thyroid dysfunction, especially in patients with a personal or family history of thyroid dysfunction. Therefore, in the case of a transition from internal administration of the drug Amiodarone to oral administration of the drug Amiodarone, both during treatment and for several months after the end of treatment, careful clinical and laboratory monitoring of thyroid function should be carried out. If thyroid dysfunction is suspected, serum TSH concentrations should be determined (using an ultrasensitive TSH test).
The drug Amiodarone contains iodine and therefore can interfere with the absorption of radioactive iodine, which can distort the results of a radioisotope study of the thyroid gland, but its use does not affect the reliability of determining the concentrations of T3, T4 and TSH in the blood plasma.
Impact on the ability to drive vehicles and machinery
There is no evidence that amiodarone impairs the ability to engage in activities requiring increased concentration and psychomotor speed. However, as a precaution, it is advisable for patients with paroxysms of severe arrhythmias to refrain from such activities during treatment with Amiodarone.