Effects of lower body negative pressure and volume loading on transmitral flow velocity pattern by pulsed Doppler...

The transmitral flow (TMF) profile was studied in 18 patients with ischemic heart disease and in 4 patients with chest pain syndrome in order to clarify the dependency of preload alteration on the pattern of TMF. Pulsed Doppler echocardiography with simultaneous measurement of right-sided cardiac catheterization and M-mode echocardiography during lower body negative pressures (LBNP 0, -10 mmHg, -20 mmHg) and Dextran infusions (Dex 100 ml, 200 ml) were used in the study. After LBNP, peak velocities in rapid filling (peak R) (cm/sec) decreased (control; 68.3 +/- 13.9, LBNP-10 mmHg; 59.8 +/- 15.2, p less than 0.01, LBNP-20 mmHg; 55.2 +/- 11.0, p less than 0.01) and the integrals in the first half phase in rapid filling (IR1) (cm) also decreased (control; 4.0 +/- 0.8, LBNP-10 mmHg; 3.4 +/- 0.9, LBNP-20 mmHg; 3.2 +/- 0.9, p less than 0.05). During Dextran infusion, peak R (cm/sec) increased (control; 53.5 +/- 7.5, Dex 100 ml; 57.8 +/- 10.0, p less than 0.05, Dex 200 ml; 60.4 +/- 10.6, p less than 0.01) as did IR1 (cm) (control; 3.2 +/- 1.1, Dex 100 ml; 3.8 +/- 1.0, p less than 0.01, Dex 200 ml; 4.2 +/- 1.3, p less than 0.01). In conclusion, changes in preload may alter the peak velocity and the first half integral in left ventricular rapid filling depending on the pattern of transmitral flow velocity.