[Effects of sublingual nifedipine on the velocity of pulse wave evaluated by Doppler echocardiography of the thoracic aorta].

Sublingual nifedipine has a rapid and powerful hypotensive effect. Its action on arterial distensibility can be assessed by measurement of pulse wave velocity (PWV) by Doppler echocardiography (DE). Ten patients were used to evaluate intra-observer reproducibility (Group 1). Fifteen hypertension patients (Group 2), not taking a calcium antagonist, 64 +/- 13 years-old, were studied by DE before and 15 minutes after 10 mg of SL nifedipine. The following were measured: systolic and diastolic blood pressures (SBP and DBP), heart rate (HR), echocardiographic shortening fraction (SF) and PWV, with sternal length (SL) taken as being identical to the length of the abdominal aorta between the isthmus and the coeliac region, and by measuring delta t: time interval for propagation of the pulsed Doppler velocimetric wave between the isthmic aorta and the coeliac aorta located by echocardiography: PWV = SL/delta t. Evidence was found in the nifedipine group (n = 15) of a fall in SBP (159.5 +/- 27.8 cf. 140.9 +/- 21 mmHg; p = 0.002); in DBP (88.6 +/- 13 cf. 79.6 +/- 8.3 mmHg; p = 0.005) and an increase in HR (72.3 +/- 10.7 cf. 76.8 +/- 12.9 bpm; p = 0.04). PWV decreased after nifedipine (10.5 +/- 3.9 cf. 7.15 +/- 12.9 bpm; p = 0.002). There was a linear correlation between the percentage reduction in PWV and left ventricular HR: y = 194x - 53; r = 0.56; p = 0.029.(ABSTRACT TRUNCATED AT 250 WORDS)