Abstract 2142: Systolic and Diastolic Dyssynchrony in Patients with Diastolic Heart Failure and the Effect of Medical Therapy
Background The prevalence of systolic and diastolic dyssynchrony in patients (pts) with diastolic heart failure (DHF) is largely unknown, including the effects of medical therapy on dyssynchrony.
Methods Sixty pts (61±9 years, 35 women) with DHF (normal EF) underwent echocardiographic imaging simultaneous with invasive measurements. An age matched control group of 35 subjects was included for comparison. Systolic and diastolic dyssynchrony were assessed by tissue Doppler (time difference between shortest and longest delays bewteen QRS and onset/peak systolic and early diastolic velocities respectively, using 4 basal segments) and defined using mean and SD in the control group (systolic:12±10, diastolic 10±9 ms).
Results Systolic dyssynchrony was present in 20 (33%, 31±25 ms,15/20 pts >60 ms). In comparison with DHF pts without systolic dyssynchrony, the 20 pts with systolic dyssynchrony had significantly worse left ventricular (LV) systolic properties (stroke work:7.1±1.8 vs 10±2.8 kg cm; end systolic pressure/end systolic volume ratio:1.9±0.3 vs 2.9±1 mmHg/ml; mid wall fractional shortening:12±1 vs 19±3%), higher mean wedge pressure (28±4 vs 20±4 mmHg) and longer tau (69±7 vs 57±4 ms) (all p<0.05). Diastolic dyssynchrony was present in 35 (58%, 20 with systolic dyssynchrony and 15 with only diastolic dyssynchrony). In the 15 pts with only diastolic dyssynchrony, LV systolic properties were similar to DHF pts without diastolic dyssynchrony (p>0.2), but mean wedge pressure (22±4 vs 18±3 mmHg) and tau (61±4 vs 55±3 ms) were significantly worse (all p<0.05). Vasodilators and diuretics led to significant improvement of diastolic dyssynchrony (39±23 to 28±20, p=0.02), but no change in systolic dyssynchrony (31±25 to 28±21 ms, p=0.15). Shortening of diastolic time delay correlated well with shortening of tau after therapy (r=0.85, p<0.001).
Conclusions Systolic dyssynchrony occurs in 33% of DHF pts and is associated with worse LV systolic and diastolic function. Diastolic dyssynchrony occurs in 58%, and is associated with worse LV diastolic function when compared with DHF pts without diastolic dyssynchrony. Medical therapy results in significant improvement of diastolic dyssynchrony which is closely related to the improvement in LV relaxation.