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[Noninvasive and quantitative evaluations of the severity of isolated pulmonary valvular stenosis using
Abstract:
The severity of isolated pulmonary valvular stenosis (PS) was evaluated noninvasively and quantitatively using two-dimensional pulsed Doppler echocardiography (2D-PDE). The subjects consisted of 17 patients with PS diagnosed by cardiac catheterization (3 to 15-year-old with a mean age of 7.9 years) and 28 healthy children (3 to 12-year-old with a mean age of 7.2 years). Flow signals by 2D-PDE were recorded in the right ventricular outflow tract just below the pulmonary valve and in the main pulmonary artery. The following three parameters were measured from the flow signals in the right ventricular outflow tract: the right ventricular pre-ejection period (RPEP) from the onset of the QRS in the electrocardiogram to the beginning of RV ejection in 2D-PDE, the acceleration time from the onset of RV ejection to peak velocity (AcT), and the right ventricular ejection time (RET) from the onset to the end of right ventricular (RV) ejection. Acceleration time index (AcT/RET), and systolic time intervals including RPEP/RET, RPEP/square root RR and RET/square root RR in PS were compared with those of the controls. The correlations between the above-mentioned parameters and pressure gradients and RV systolic pressures in PS were examined. Data were expressed as mean value +/- SD. AcT/RET ranged from 0.37 to 0.53 (0.45 +/- 0.04) in the controls and from 0.54 to 0.76 (0.62 +/- 0.07) in PS. The mean AcT/RET was significantly greater in PS than in the controls (p less than 0.001). There was a highly positive correlation of AcT/RET with pressure gradients (r = 0.94) and RV systolic pressures (r = 0.93). RPEP/RET ranged from 0.32 to 0.47 (0.37 +/- 0.04) in the controls and from 0.24 to 0.35 (0.29 +/- 0.03) in PS, and the mean was significantly lower in PS than in the controls (p less than 0.001), and this was caused by the short RPEP and prolonged RET. RPEP/square root RR ranged from 102 to 160 msec (122 +/- 16 msec) in the controls and from 86 to 136 msec (107 +/- 16 msec) in PS, and the mean was significantly shorter in PS (p less than 0.05). RET/square root RR ranged from 300 to 345 msec (323 +/- 13 msec) in the controls and from 308 to 417 msec (363 +/- 27 msec) in PS, and the mean was significantly longer in PS (p less than 0.001). The pressure gradient and RV systolic pressure in PS did not correlate with RPEP/RET, RPEP/square root RR and RET/ square root RR.4+ 102 to 160 msec (122 +/- 16 msec) in the controls and from 86 to 136 msec (107 +/- 16 msec) in PS, and the mean was significantly shorter in PS (p less than 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)