Mechanisms in the genesis of recurrent ventricular tachyarrhythmias as revealed by clinical electrophysiologic studies

The effect of medical and surgical treatment on subsequent sudden cardiac death in patients with coronary artery disease: a report from the Coronary Artery Surgery Study

The effect of medical and surgical treatment on subsequent sudden cardiac death was assessed in 13,476 patients in the Coronary Artery Surgery Study registry who had significant coronary artery disease, operable vessels, and no significant valvular disease. (Patients were assigned to medical or surgical therapy on the basis of clinical judgment and not according to a randomization scheme; therefore, biases associated with unknown variables could not be evaluated.) Sudden cardiac death occurred in 452 patients (3.4%) during a mean follow-up of 4.6 years. Five year survival free of sudden death for medically treated patients was 94 +/- 0.3%, and that for surgically treated patients was 98 +/- 0.2% (p less than .0001). Twelve baseline clinical, electrocardiographic, and angiographic variables were significantly different between patients alive at the last follow-up and those suffering sudden death. Data on these variables were available for 11,508 patients. Sudden death occurred in 257 (4.9%) of 5258 medically treated and 101 (1.6%) of 6250 surgically treated patients. In a high-risk patient subset with three-vessel disease and history of congestive heart failure, 91% of surgically treated patients had not suffered sudden death compared with 69% of medically treated patients. After Cox survival analysis was used to correct for baseline variables, surgical treatment had an independent effect on sudden death (p less than .0001). This reduction was most pronounced in high-risk patients.

The stabilizing and unstabilizing influences of neurogenic and vascular activities of the heart as related to sudden cardiac death

Despite the frequency with which sudden cardiac death occurs in affluent societies, little is known about the precise mechanisms by which it is caused. Practically nothing is known about why sudden cardiac death occurs in one but not another person. It is difficult to escape the conclusion that in many instances, the final events occur almost by chance. Therefore, it would appear that every effort should be made by the physician to assist in preventing the changes, that is, cardiomegaly and myocardial ischemia, that appear to be potential markers of sudden cardiac death in many persons. Attention should be directed toward identifying and facilitating stabilizing neurogenic and vascular activities and identifying, controlling and reversing unstabilizing influences likely to foster sudden cardiac death. In the absence of a more complete knowledge of precise mechanisms, the efforts of the physician should be directed toward behavior modifications that appear to reduce the clinical manifestations of coronary heart disease which contribute to the development of cardiomegaly and myocardial ischemia.