Effects of left ventricular diastolic dysfunction on exercise capacity three to six weeks after acute myocardial infarction in men.
To examine the effects of left ventricular (LV) diastolic dysfunction on exercise capacity, hemodynamic and radionuclide responses were measured at rest and during exercise in 50 patients with recent myocardial infarction. The ratio of an increase in pulmonary arterial wedge pressure (PAWP) to an increase in LV end-diastolic volume (EDV) from rest to peak exercise (delta PAWP/delta EDV) was used as an index of LV diastolic function, delta PAWP/delta EDV had modest and negative correlations with peak oxygen consumption (VO2), cardiac output, and stroke volume in all patients. Among patients with peak VO2 > or = 20 ml/min/kg (group I, n = 24) and those with peak VO2 < 20 ml/min/kg (group II, n = 26), there were no differences between the 2 groups with regard to resting LV ejection fraction, EDV, PAWP, cardiac output, and stroke volume. Although there was no significant difference in LV ejection fraction at peak exercise, group II had significantly reduced EDV, increased PAWP, and decreased cardiac output and stroke volume than those in group I. As a result, delta PAWP/delta EDV was significantly higher in group II. These results suggest that LV diastolic dysfunction has a key role in determining exercise capacity in patients with reduced exercise capacity after recent myocardial infarction.
Yuasa
F
F
Second Department of Internal Medicine, Kansai Medical University, Osaka, Japan.
Sumimoto
T
T
Takeuchi
M
M
Kaida
M
M
Hattori
T
T
Jikuhara
T
T
Nakamura
S
S
Sugiura
T
T
Iwasaka
T
T
Inada
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D002302:Cardiac Output; D003971:Diastole; D005080:Exercise Test; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology*; D010101:Oxygen Consumption; D005082:Physical Exertion; D011669:Pulmonary Wedge Pressure; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*