Abstract 3813: Hemodynamic Characterizations in Patients with Diastolic Heart Failure and Hypertension
Background: Hypertension is thought to play an important role in diastolic heart failure (DHF); however, DHF has different underlying pathophysiologic mechanisms. Hemodynamic characterizations in DHF with or without hypertension have not been compared.
Methods: A conductance catheter with microtip-manometer was used to measure left ventricular (LV) function and hemodynamics in 16 DHF patients (pts) with hypertension (hypertensive DHF: 73±8 yrs) and 12 pts without hypertension (non-hypertensive DHF: 60±10 yrs). Pts with heart failure and ejection fraction above 50% were diagnosed as DHF. After baseline measurements, nitroglycerin (NTG) was infused and measurements were repeated.
Results: End-systolic pressure was significantly higher and the time constant of LV relaxation (Tau) was significantly longer in hypertensive DHF than non-hypertensive DHF. The peak of loading sequence in non-hypertensive DHF was early in systole, while that in hypertensive DHF was late in systole. NTG decreased LV end-systolic and end-diastolic pressure in both group without any changes in heart rate. In non-hypertensive DHF, NTG significantly reduced end-diastolic volume and stroke volume (70±30 vs. 65±32 ml), and shortened Tau (39±7 vs. 36±9 ms) without any changes in the time to peak LV force. By contrast, in hypertensive DHF, NTG significantly reduced end-systolic volume as well as end-diastolic volume, resulting in the preserved stroke volume (62±20 vs. 63±22 ml). Furthermore, NTG shifted the peak of LV loading sequence from late to early systole and shortened the time to peak LV force (258±46 vs. 182±53 ms) accompanied with shortened Tau (44±13 vs. 36±10 ms).
Conclusions: The peak of loading sequence was late in systole in hypertensive DHF, while early in systole in non-hypertensive DHF. Furthermore, changing loading sequence had favorable effect on LV relaxation, and maintained stroke volume in hypertensive DHF.