The Effect of Postmenopausal Hormone Replacement Therapy on Cardiovascular Performance

Summary: Postmenopausal hormone replacement therapy (HRT) has usually been evaluated the relationship with atheroscle- rotic disease, whereas its effect on direct cardiac functions hasn't been investigated in detail. This study was planned to investigate the long-term effects of HRT on cardiac functions and exercise performance. Methods: Thirty-six postmenopausal women (mean age: 51 ± 4 years, 39-60 years) were prospectively analyzed with pulsed wave Doppler echocardiography and symptom-limited exercise stress test before HRT (oral 0.625 mg conjugated estrogen and 2.5 mg medroxyprogesteron acetate/day), and at the third and the sixth months. The effect of HRT on left ventricular ejection fraction (EF), early filling velocity (E wave) and late filling velocity (A wave), E wave deceleration time (EDT), E/A ratio, myocardial performance index (MPI), exercise duration and METS changes were examined. Results: HRT did not significantly alter the left ventricular EF. At the third month of HRT, there was an insignificant increase in E wave, EDT, and E/A ratio, whereas an insignificant decrease was noted in MPI (P>0.05). However, at the sixth month of HRT, these changes became significant (68±12 vs. 75 ± 13 cm/s, P<0.01; 171 ±24 vs. 184 ± 14 ms, P<0.01; 1.01±0.23 vs. 1.11±0.27, P<0.01, and 44±9 vs. 39±8%, P<0.001, respectively). On the other hand, exercise duration and exercise METS values showed significant improvements at the third month of IIRT (423± 104 vs. 482±104 s. P<0.001; 8.2±1.7 vs. 9.1±2 METS, P<0.001). These improvements also continued at the sixth month of IIRT. In conclusion, postmenopausal HRT leads to a progressive improvement on left ventricular function parameters, and in parallel, in exercise performance.