Survival of patients with a strongly positive exercise electrocardiogram.

To assess the prognosis of patients with a strongly positive exercise ECG, the 5-year cumulative survival rate was computed for 220 medically treated patients. Of these patients, 107 had coronary angiograms (group A) and 113 did not (group B). All had horizontal or downsloping ST depression greater than or equal to 2 mm during a multistage Bruce protocol treadmill exercise test. In group A, the overall 5-year survival rate was 74 +/- 5%. Survival decreased with decreasing duration of exercise: All patients who achieved stage IV (541 seconds or more) survived, whereas the survival rate was 86 +/- 6% when the patients terminated their exercise during stage III (361 - 540 seconds), 73 +/- 7% when during stage II (181 - 360 seconds) and only 52 +/- 13% when during stage I (180 seconds or less). The mortality was associated with more severe coronary artery disease, and sudden death was the main cause of death. Patients in group B had a longer mean exercise duration than those in group A and, as expected, a higher survival rate (91 +/- 3%, p less than 0.01), which also varied according to the exercise duration. Among patients with a strongly positive exercise ECG, the duration of exercise identifies subsets that have different survival rates.