[Electric stability of the heart after myocardial infarction: role of anti-arrhythmia agents during postinfarction].
Electrical instability of the heart after myocardial infarction threatens surviving patients with sudden death from a severe ventricular arrhythmia. These arrhythmic complications are usually the result of several factors: an arrhythmogenic substrate corresponding to the ischaemic myocardium, a trigger factor (usually a ventricular extrasystole) and other predisposing factors (autonomic nervous system, electrolyte imbalance, activation of the renin-angiotensin system). Risk stratification of electrical instability combines noninvasive (Holter, exercise testing, signal averaged electrocardiography, study of the variability of the heart rate, radionuclide or echocardiographic evaluation of the left ventricular ejection fraction) and invasive investigations (coronary angiography and even programmed ventricular stimulation). The presence of late ventricular potentials, a low ejection fraction and/or a ventricular arrhythmia on Holter monitoring identifies a high risk subgroup. Although the assessment of electrical instability is better than it used to be, pharmacological prevention remains disappointing. Class I antiarrhythmics are ineffective or dangerous. The efficacy of Class III antiarrhythmics is uncertain and only the betablockers seem to have any beneficial effects on this post-infarction electrical instability.
Service de cardiologie, hôpital central, CHU de Nancy.
N
N
Sadoul
E
E
Aliot
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000517:prevention & control; D015716:Electrocardiography, Ambulatory; D005080:Exercise Test; D006801:Humans; D009203:Myocardial Infarction / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D011379:Prognosis; D012306:Risk; D016277:Ventricular Function, Left
D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents
La stabilité électrique du coeur après infarctus du myocarde: place des antiarythmiques dans le postinfarctus.