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To determine the relative value of electrocardiographic (ECG) ST-segment depression alone compared to angina alone for predicting multivessel coronary artery disease during early and repeat postinfarction exercise tests, we evaluated 93 postmyocardial infarction patients with modified treadmill exercise tests prior to hospital discharge (mean 14 ± 2 days), and 36 of these 93 patients with repeat exercise tests at six weeks following infarction. It was concluded that angina alone or angina irrespective of the presence of ST-segment depression are better predictors of multivessel coronary artery disease than ECG ST-segment depression alone, and the persistence of ischemic abnormalities during repeat treadmill exercise tests following infarction is useful for confirming the presence of multivessel coronary artery disease.

In 38 patients undergoing elective coronary arterial bypass graft surgery, the radiographic dimension of the left side of the heart was determined and echocardiographic studies were performed before and after surgery. On the plain chest x-ray film one week after surgery, all patients showed an increase in the size of the left side of the heart, which usually was not accompanied by an increase in the echocardiographic left ventricular end-diastolic dimension; however, in 25 patients, pericardial fluid was detected soon after surgery, which would explain the enlarged cardiac silhouettes. Several months after surgery, the radiographic size of the heart returned to the preoperative value in most patients, and pericardial fluid was no longer demonstrated on the echocardiogram. Thus, pericardial fluid frequently is found in the first week following coronary arterial bypass graft surgery and may give the impression of increased cardiac size on plain chest x-ray films; however, echocardiographic studies provide a more accurate estimate of left ventricular size and reveal the presence of pericardial effusion.

Among 28 patients with chronic obstructive pulmonary disease (COPD) with increasing dyspnea, the resting mean pulmonary arterial wedge pressure was elevated (>12 mm Hg) in 4 and became abnormal with exercise in 3 other subjects. Stroke volume index was reduced (<36 ml/beat/M2) in 16 of 26 patients (62 percent). The resting pre-ejection period index was prolonged (>144 msec) in 17 patients (65 percent), while the left ventricular (LV) ejection time index was reduced (<408 msec) in 23 patients (88 percent). The ratio of the pre-ejection period to the LV ejection time was within the normal range (0.309 to 0.381) in only 3 of 26 patients (12 percent). Echocardiographic measurements of LV function were normal in nine patients, seven of whom had one or more abnormal values for systolic time intervals (STIs). These data suggest that reduced LV filling results in abnormal values for STIs in patients with COPD, and therefore that in such patients STIs are not accurate indices of LV function.

In order to determine the relative efficacy and dose equivalency of propranolol four times a day and nadolol once daily for the treatment of stable angina pectoris, ten patients were studied in a double blind randomized placebo controlled crossover study. Total daily doses of propranolol and nadolol were determined by titrating until an equivalent degree of reduction in the heart rate response to exercise was achieved. At these doses, the treadmill exercise time to 0.1 mV of electrocardiographic ST-segment depression was increased from 248 ± 75 seconds on placebo to 405 ± 56 seconds on propranolol (p<0.05) and 471 ± 46 seconds on nadolol (p<0.01). Also, the mean frequency of angina decreased from eight attacks per week on placebo to three on propranolol and nadolol (both p<0.05). In six of the ten patients, the effective total daily dose of propranolol and nadolol was identical, and the dose ratio for all ten patients was 1.17:1, propranolol to nadolol. However, individual dose titration is recommended when switching from propranolol four times a day to nadolol once daily because of the dosage variability noted in 40 percent of the patients.

In patients with chronic obstructive pulmonary disease (COPD), the clinical differentiation between dyspnea due to left ventricular dysfunction and that due to pulmonary events is difficult. Invasive techniques have been the only reliable diagnostic approach. To assess the potential value of noninvasive techniques in this context, 27 patients with COPD and with clinically suspected left ventricular dysfunction were studied by echocardiography, radionuclide angiography, and right cardiac catheterization. In 20 (74 percent), adequate echocardiograms were obtained. Of these 20 patients, 17 had normal pulmonary arterial wedge pressures at rest and during submaximal handgrip exercise. Sixteen of these 17 had normal left ventricular performance by all three echocardiographic criteria used; in one patient, two criteria were not interpretable, but the third was normal. Results of radionuclide studies were normal in 15 patients, borderline in one, and not measurable in one. Of the three patients with abnormal wedge pressures, at least one echocardiographic criterion was abnormal in all. Radionuclide data were abnormal in two and not measurable in one. We conclude that left ventricular dysfunction is infrequently present in patients with COPD in whom such dysfunction is clinically suspected, that the two noninvasive techniques described here can be applied successfully to a high percentage of patients with COPD, and that the agreement among echocardiographic, radionuclide, and wedge pressure data is excellent.