Cosyns B, van Camp G, Friart A, Vandenbossche J L
Saint-Pierre University Hospital, Cardiology Department, Brussels, Belgium.
Int J Card Imaging. 1995 Mar;11(1):55-8. doi: 10.1007/BF01148954.
The Doppler indexes of tricuspid porcine bioprosthetic valves were evaluated in twelve patients without clinical and two-dimensional echocardiographic evidence of valve dysfunction. Peak and mean pressure gradients across the prostheses were measured using the simplified Bernoulli equation. All the Doppler measurements were compared during inspiration and expiration. During inspiration peak velocity, peak gradient and mean gradient (1.52 +/- 0.28 m/s; 9.7 +/- 3.05 mmHg; 4.07 +/- 1.16 mmHg) were significantly higher than during expiration (1.28 +/- 0.8 m/s; 6.58 +/- 2.7 mmHg; 2.98 +/- 1.13 mmHg; p < 0.01) but pressure half time was not significantly different (122 +/- 62 ms versus 134 +/- 75 ms; p > 0.05). Inspiratory range of peak velocities, peak gradients, mean gradients and pressure half times were respectively 0.8-2.04 m/s; 4.9-16.6 mmHg; 1.2-7.2 mmHg; 42-340 ms while expiratory range of values was 0.8-1.93 m/s; 2.6-15 mmHg; 1.1-5.7 mmHg; 46-345 ms. These data suggest that even very long pressure half times do not indicate valve dysfunction. This study demonstrates that large variation of Doppler parameters are present during respiration and could produce inaccuracy in the assessment of bioprostheses in tricuspid position if they are not taken in consideration.
在12例无临床症状且二维超声心动图无瓣膜功能障碍证据的患者中，对猪三尖瓣生物瓣膜的多普勒指数进行了评估。使用简化的伯努利方程测量假体两端的峰值和平均压力梯度。在吸气和呼气期间对所有多普勒测量值进行比较。吸气时的峰值速度、峰值梯度和平均梯度（1.52±0.28 m/s；9.7±3.05 mmHg；4.07±1.16 mmHg）显著高于呼气时（1.28±0.8 m/s；6.58±2.7 mmHg；2.98±1.13 mmHg；p<0.01），但压力减半时间无显著差异（122±62 ms对134±75 ms；p>0.05）。峰值速度、峰值梯度、平均梯度和压力减半时间的吸气范围分别为0.8 - 2.04 m/s；4.9 - 16.6 mmHg；1.2 - 7.2 mmHg；42 - 340 ms，而呼气时的值范围为0.8 - 1.93 m/s；2.6 - 15 mmHg；1.1 - 5.7 mmHg；46 - 345 ms。这些数据表明，即使压力减半时间很长也不表明瓣膜功能障碍。本研究表明，呼吸期间多普勒参数存在很大变化，如果不加以考虑，可能会在评估三尖瓣位生物瓣膜时产生不准确结果。
