INCREASE IN LEFT-VENTRICULAR EJECTION RATE DURING RECOVERY FROM EXERCISE IN PATIENTS WITH MYOCARDIAL-INFARCTION

Changes in left ventricular (LV) ejection rate were evaluated during supine bicycle exercise and recovery in 12 patients with anterior myocardial infarction. Pulmonary artery wedge pressure (34 +/- 9 to 14 +/- 5 mm Hg) and plasma norepinephrine level decreased at 2 min recovery from peak exercise, whereas plasma lactate tended to increase. As a result, LV ejection rate reached the highest value at 2 min of recovery. Thus, both cardiac (optimal filling pressure) and peripheral factors (reduced vascular resistance) caused the increase in LV ejection rate at early recovery.