Department of Surgery, Kurume University Hospital, Kurume, Fukuoka, Japan.
Ann Thorac Surg. 2010 Mar;89(3):745-50. doi: 10.1016/j.athoracsur.2009.12.034.
Small valve size and prosthetic patient mismatch are both considered to have harmful effects on residual left ventricular hypertrophy after aortic valve replacement for aortic stenosis. In general, it is believed that the effective orifice area index of the prosthesis must not be less than 0.85 cm(2)/m(2) in order to avoid prosthetic patient mismatch. On the other hand, studies have shown that valve type and valve size had no effects on postoperative left ventricular mass (LVM). The objective of this report was to examine the relationships between patient characteristics or the prosthetic valve and postoperative LVM.
To evaluate the factors that influence postoperative LVM, we formulated the hypothesis that postoperative LVM is proportional to the sum total of pressure at the prosthetic valve orifice and inner surface area of the left ventricle in systole. We present a conceptually new index for postoperative LVM and compare the index with postoperative LVM.
The results indicated a strong correlation between the new index and postoperative LVM six years after surgery (r(2) =0.67, p < 0.0001). As might be expected, LVM increased gradually as the value of the new index increased.
The results of the present study indicate that postoperative left ventricular hypertrophy can be avoided by preventing postoperative hypertension in patients without left ventricular dilatation and an effective orifice area index is greater than 0.77 cm(2)/m(2).
主动脉瓣置换术治疗主动脉瓣狭窄时,瓣膜尺寸小和人工瓣膜与患者不匹配均被认为对左心室肥厚残留有不良影响。一般认为,为避免人工瓣膜与患者不匹配,人工瓣膜有效开口面积指数不得小于 0.85cm(2)/m(2)。另一方面,研究表明瓣膜类型和瓣膜尺寸对术后左心室质量(LVM)无影响。本报告的目的是研究患者特征或人工瓣膜与术后 LVM 之间的关系。
为评估影响术后 LVM 的因素,我们假设术后 LVM 与人工瓣膜瓣口处的总压力和收缩期左心室内表面面积之和成正比。我们提出了一个新的术后 LVM 指数概念,并将其与术后 LVM 进行了比较。
结果表明,术后 6 年新指数与术后 LVM 之间存在很强的相关性(r(2)=0.67,p<0.0001)。正如预期的那样,随着新指数的增加,LVM 逐渐增加。
本研究结果表明,对于无左心室扩张且有效开口面积指数大于 0.77cm(2)/m(2)的患者,通过预防术后高血压可以避免术后左心室肥厚。