Preload-dependent variation of the propagation velocity in patients with congestive heart failure.

Background: Although color Doppler M-mode propagation velocity (Vp) is preload-independent, the variation in Vp with the temporal variation of preload in the clinical setting has not been evaluated. Because left ventricular filling pressure changes dramatically with treatment of congestive heart failure (CHF), we hypothesized that preload-dependent variations in Vp occur with treatment of CHF.

Methods: We performed Doppler echocardiographic and hemodynamic evaluation in 24 patients with CHF (15 men, 62 +/- 10 years) at initial presentation (baseline study) and after CHF had improved with therapy (second study).

Results: The interval between the baseline and the second study was 48.6 +/- 21.5 hours. Vp decreased between the baseline study (41 +/- 5 cm/s) and the second study (28 +/- 5 cm/s, P <.0001). Only the change in pulmonary capillary wedge pressure (-8.3 +/- 3.3 mm Hg) between the baseline and second study was an independent predictor of the change in Vp (-12.5 +/- 5.9 cm/s) by stepwise linear regression (r = 0.68, P =.0002).

Conclusions: Vp decreases significantly with decreases in pulmonary capillary wedge pressure with the treatment of CHF. The preload-dependent variation should be taken into account in the assessment of Vp in patients with CHF.