SIldenafil and Diastolic Dysfunction after Acute Myocardial Infarction in Patients with Preserved Ejection Fraction: SIDAMI
Background—Diastolic dysfunction is frequently seen after myocardial infarction (MI) and is characterized by a disproportionate increase in filling pressure during exercise to maintain stroke volume. We hypothesized that sildenafil would reduce filling pressure during exercise in patients with diastolic dysfunction after MI.
Methods and Results—Seventy patients with diastolic dysfunction and near normal left ventricular (LV) ejection fraction on echocardiography were randomly assigned sildenafil 40 mg thrice daily or matching placebo for 9 weeks. Before randomization and after 9 weeks of treatment patients underwent simultaneous echocardiography and right heart catheterization at rest and during exercise. Primary endpoint was pulmonary capillary wedge pressure (PCWP), secondary endpoints comprised cardiac index (CI) and pulmonary arterial pressure (PAP) at rest and during exercise after 9 weeks. After 9 weeks there were no differences in PCWP at rest (13±4 vs. 13±3 mmHg, p=0.25) or at peak exercise (35±8 mmHg vs. 31±7 mmHg, p=0.07). However with treatment CI increased at rest (p=0.006) and peak exercise (p=0.02) in the sildenafil group, systemic vascular resistance index (resting, p=0.0002; peak exercise, p=0.007) and diastolic blood pressure (resting, p=0.005; peak exercise, p=0.02) were lower in the sildenafil group. Resting LV end-diastolic volume index (LVEDVI) increased (p=0.001) within the sildenafil group but was unchanged in the placebo group.
Conclusions—Sildenafil did not decrease filling pressure at rest or during exercise in post-MI patients with diastolic dysfunction. However, there were effects on secondary endpoints which require further studies.
- acute myocardial infarction
- diastolic dysfunction
- cardiac catheterization
- exercise testing
- exercise echocardiography
- Received November 21, 2012.
- Accepted January 30, 2013.
- Copyright © 2013, Circulation