Sudden cardiac death -- 1978.

SUMMARY With the development of coronary care units in the 1960s, attitudes toward sudden cardiac death (SCD) began to change as physicians learned that cardiac arrest was reversible. The problem of SCD has two aspects an acute, precipitating factor and a chronic predisposition to electrical instability of the myocardium. Resolution of the problem requires identification and protection of the potential victim. Ven-tricular premature complexes (VPCs) have been related to the development of serious arrhythmias and early death, but the mere presence of VPCs does not discriminate risk of subsequent fatality. VPCs should be graded according to frequency, persistence, multiformity, repetitive pattern and degree of prematurity. Provocation of repetitive extrasystoles by R-on-T pacing may indicate the presence of a reduced threshold for ventricular fibrillation (VF). Prophylactic antiarrhythmic therapy may help protect patients resuscitated from VF against recurrent cardiac arrest. Neuropharmacologic factors perhaps affecting central nervous system sympathetic activity can alter cardiac vulnerability and may protect against VF. Findings in dogs indicate that psychologic stress can reduce the cardiac threshold for VF. If psychologic factors predispose to ventricular arrhythmias by increasing the level of sympathetic tone, lessening neural sympathetic activity should reduce the incidence of SCD. SUDDEN CARDIAC DEATH (SCD) is one of the major challenges to contemporary cardiology. Its sheer magnitude demands attention, claiming over 400 thousand lives annually, or about 60% of all coronary heart disease fatalities. The problem of sudden death has been recognized since the beginning of recorded history, yet before the 1960s, SCD received scant attention from clinical and research communities. In part this related to the prevailing perception that SCD was the ultimate expression of severe, far-advanced and irreversible coronary athero-sclerosis. Since the SCD was unexpected and struck down the seemingly healthy subject outside the hospital , the physician deemed it an act of fate before which he or she was largely helpless. As is often true in science, new methodologies not only usher in new content, but also mold new attitudes. In the case of SCD it was the burgeoning coronary care units (CCU) of the 1960s that stimulated a new direction. CCU experience largely dispelled the sense of futility, for it became rapidly evident that cardiac arrest was reversible. Patients promptly resuscitated from primary electrical failure consistently recovered and survived for variable and prolonged periods determined by the extent of their underlying heart disease. Because ventricular fibrilla-tion (VF) had its highest incidence at the …