Pulmonary blood flow profiles with reduced right ventricular function in lambs

Abstract

The determinants of right ventricular (RV) performance with damaged RV free wall, such as occurs with RV infarction, are still unclear. Using 20-MHz Doppler ultrasound equipment, we investigated the changes in pulmonary blood flow velocity profiles before and after ligation of the right coronary artery. RV dp/dt, stroke volume, RV stroke work, aortic pressure and cardiac output decreased and central venous pressure rose after the ligation. The RV stroke work-end-diastolic pressure relationship indicated impaired RV function following ligation. We observed shortened acceleration time (65.0 +/- 15.1 vs 54.4 +/- 6.2 ms, P < 0.05) and reduced maximum velocity of forward flow (59.0 +/- 5.9 vs 52.5 +/- 7.6 cm/s, P < 0.05) after the ligation. Acceleration was interrupted earlier after ligation than before ligation. These alterations in flow are thought to be a consequence of the altered movement of the RV free wall and ventricular septum induced by RV infarction.

Doppler Echocardiographic Study of Right Ventricular Systolic Performance in Inferior Myocardial Infarction

“…10,12 Recently, experimental studies have reported the potential usefulness of the pulmonary flow patterns in the evaluation of right ventricular performance in the experimental RV infarction. 13 The goal of the study was to assess RV systolic performance in patients with inferior MI by means of Doppler echocardiography of pulmonary flow and to correlate them with hemodynamic findings.…”