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The efficacy of continuous and intermittent nitroglycerin patches (10 mg/day) was compared in a randomized, placebo-controlled trial in 36 patients with stable angina and reproducible, exercise-induced ST depression. Intermittent treatment was administered either 18 or 14 h/day with an intermission of 6 h or 10 h, respectively. Exercise tests were performed during the last 2 h of patch application. Compared with placebo, neither continuous nitroglycerin nor the two intermittent regimens prolonged total treadmill time or time to 1 mm ST depression. No treatment eliminated exercise-induced ST depression in greater than 1 of the 36 patients. Time to angina was prolonged (by 40 +/- 66 s) only during the "10 h off" treatment (p = 0.001); time to angina increased by greater than or equal to 20% in 13 patients. Responders to treatment could be predicted by a short history of angina (p less than 0.05) and a time to angina less than or equal to 250 s during the placebo test. For each treatment, greater than or equal to 25 of the patients reported headache; 4 additional patients dropped out because of severe headache and 2 others because of a coronary event in a washout period. Thus, in most patients with stable angina, side effects outweight any benefit demonstrable with this therapy.

The increased exercise capacity after physical training in patients with coronary artery disease has been attributed to improved oxygen supply to the myocardium by way of increased collateral circulation or reduction of myocardial oxygen consumption by extracardiac factors, or both. Fourteen patients aged 43 to 61 years (mean 51 years) with 50 percent or greater obstruction in one, two or three vessels (three, six and five patients, respectively) underwent 13 months of physical training. Clinical status was either stable or improved with training. Treadmill exercise capacity, as measured by oxygen consumption, increased 25 percent from 21.9 ± 4.8 (standard deviation) to 27.4 ± 4.1 ml/kg-min at heart rates of 154 ± 17 and 156 ± 12 beats/min, respectively. After training, new collateral vessels, apparently secondary to progression of the disease, were observed in 2 of 21 arteries significantly but not completely obstructed before training. These data are in contrast to those reported for trained dogs with incomplete obstruction. Coronary arterial lesions progressed in only 4 of 14 patients. Coronary arteriographic data from this laboratory do not support the hypothesis that the increased exercise capacity after training in patients with coronary disease can be attributed to the development of collateral circulation. It is possible that physical training may retard the progression of coronary artery disease.

A relatively rapid procedure for the routine estimation of lipoproteins in prestained human sera by zone electrophoresis in paper was described. This technique was employed for the study of the percentage of alpha-lipoproteins in sera of healthy and coronary male subjects of various ages. The mean proportion of alpha-lipoproteins in healthy males (100) was observed to be about 24% in subjects at the age of 20–29 and 16% at the age of 30–59. In the coronary group (105) the mean percentage of alpha-lipoproteins was lower than 13% irrespective of age. From this study, the diagnostic value of alpha-lipoproteins percentage to characterize a coronary patient appeared to be superior to total cholesterol concentrations.

A 61-year-old white woman presented a history of advanced vascular disease of approximately fifteen years' duration, resulting from hypertensive and arteriosclerotic cardiovascular disease. Following an acute posterolateral myocardial infarction, she went into sudden collapse lasting approximately five minutes. Ventricular fibrillation was actually recorded over a period of 1 minute and 47 seconds and then spontaneously reverted to a normal sinus rhythm. Her convalescence was uneventful and she was discharged without any evidence of cerebral deterioration.