Determinants of forward pulmonary vein flow: An open pericardium pig model

摘要: Abstract OBJECTIVE To elucidate determinants of pulmonary venous (PV) flow. BACKGROUND Right ventricular (RV) systolic pressure (vis a tergo), left atrial (LA) relaxation and (LV) systole fronte) have been suggested as the anterograde Doppler flow velocities, but their relative contributions to those velocities not quantified. METHODS We analyzed, by multiple regression analysis, PV in an open-pericardium, paced (70 90 beats/min) pig model which LA afterload was modified creating LV regional ischemia (left anterior descending coronary artery constriction). measured high fidelity LA, RV pressures (epicardial echocardiography). calculated tau, (a through x difference divided time, normalized pressure), peak v (RVSP-v) differences, ejection fraction, long-axis shortening, stroke volume (LV outflow integral × area) four-chamber dimensions, transmitral velocity-time integrals. RESULTS Left increased mildly y trough (8 ± 1 vs. 6 mm Hg, p = 0.001). (coefficient: 0.5 cm/ml, SE: 0.2, 0.005) −0.8 cm/mm 0.3, 0.008) determined total integral. both early velocity 0.04). maximum area 2 cm−1, 0.7, 0.01) RVSP-v 0.1 0.05, 0.03) late The diastolic 1.2, CONCLUSIONS In experimental acute limited duration, main independent predictors are compliance (LA pressure) systole—all vis fronte factors. setting pressures, reservoir filling) is predictor conduit).