Approaches to Sudden Death from Coronary Heart Disease

Abstract

Sudden cardiac death (SCD) continues unabated. Coronary care units, while effective in lowering hospital mortality, cannot significantly reduce SCD which occurs primarily outside the hospital and accounts for the majority of deaths from coronary heart disease (CHD). In view of the frequent precipitous nature of SCD, only a program which identifies and protects the victim prior to the event can hope to be successful in preventing the majority of SCD. Since it is likely that SCD is due to an arrhythmia, drug prophylaxis might prove effective. In view of the toxicity of currently available agents, it is mandatory to preselect a population at highest risk before embarking on a drug trial. Ventricular premature beats (VPB) may identify subjects susceptible to SCD. Epidemiologic and physiologic information on VPB is reviewed, and proposals are made for studies designed to establish the usefulness of VPB as a risk factor for SCD.

Continuous electrocardiographic monitoring in patients with sickle‐cell anemia during pain crisis

“…The ventricular arrhythmias were graded according to the Lown classification as follows: No ventricular premature contractions (VPCs), LO; unifocal VPCs, L,; unifocal VPCs greater than 10/h, Lz; multifocal VPCs, L3; paired VPCs, Lq; and ventricular tachycardia, Ls. This classification has been used to evaluate patients after myocardial infarction and may have prognostic significance in terms of sudden death as well as correlation with the severity of the disease (Lown, 1976). Atrial arrhythmias were graded similarly and designated by the letter K. K5 included atrial fibrillation, paroxysmal atrial tachycardia, and atrial flutter.…”

Elevation of ventricular defibrillation threshold in dogs by antiarrhythmic drugs

“…A population of patients especially prone to sudden death may be identified [1,2], for whom some authors have proposed prophylactic treatment with procaine amide or related drugs in selected cases [3,4]. Intravenous lidocaine by bolus injection or continuous infusion is currently recommended for hospitalized patients following acute myocardial infarction in order to prevent ventricular fibrillation [5,6].…”

Sudden cardiac death recorded during ambulatory electrocardiographic monitoring

“…Ventricular arrhythmias were characterized as so-called warning arrhythmias when they could be categorized into the Lown class 111-V (Lown and Wolf, 1971). R on T extrasystoles are defined as premature ventricular beats which interrupt the T wave of the preceding sinus beat (corresponding to the Lown class V).…”

“…Preceding events of the bradyarrhythmias were ventricular arrhythmias of the Lown grade 111-V (Lown and Wolf, 1971) in 4 of 8 patients. In the other 4 patients only rare ventricular premature beats could be detected in the Holter recordings before cardiac arrest.…”

“…Nevertheless, these high-grade ventricular arrhythmias demonstrate a marked degree of electrical instability within the heart. Furthermore, the high incidence of serious rhythm disturbances in the setting of sudden cardiac death underlines the importance of the Lown grading concept of ventricular arrhythmias (Lown and Wolf, 1971). …”