Department of Cardiology, Heart Center, Gent University Hospital, Belgium.
Department of Cardiology, Heart Center, Gent University Hospital, Belgium.
Int J Cardiol. 2018 May 1;258:305-312. doi: 10.1016/j.ijcard.2018.01.014.
We recently reported the feasibility of the average pixel intensity (API) method for grading mitral regurgitation (MR) in a heterogeneous MR population. Since mitral valve prolapse (MVP) is an important cause of primary MR, we more specifically investigated the feasibility of the API method and the MR flow dynamics in patients with MVP.
Transthoracic echocardiography was performed by a single operator in consecutive MVP patients (n=112). MR was assessed using the API method, color Doppler, vena contracta width (VCW), effective regurgitant orifice area (PISA-EROA) and regurgitant volume (PISA-RV).
The API method was feasible in 89% of all MVP patients (68%, 71% for VCW and PISA method, respectively ;p<.001). Inter- and intra-observer correlations for API in MVP with non-holosystolic MR were 0.989 and 0.995. For the overall MVP-MR population, API had significant correlations with direct and indirect measures of MR severity. Based on ROC curves, an API cutoff value of 125 au was suggested to identify severe MR in MVP and a MR duration/systolic time ratio<100% (i.e. non-holosystolic MVP-MR) identifies patients with non-severe MR (API<125), whereas the majority of holosystolic MVP had severe MR (API>125). Finally, API analysis of the proto-, mid- and telesystolic phases of MR in MVP showed different kinetics in non-holosystolic compared to holosystolic MVP.
The API method is a feasible and reproducible method for grading MVP-MR. As the API method takes into account the temporal MR flow changes during the entire systolic cycle, it may be of added value in clinical practice.
我们最近报道了平均像素强度（API）方法在异质性二尖瓣反流（MR）人群中分级的可行性。由于二尖瓣脱垂（MVP）是原发性 MR 的重要原因，我们更具体地研究了 API 方法在 MVP 患者中的可行性以及 MR 流量动力学。
由一位操作人员连续对 MVP 患者（n=112）进行经胸超声心动图检查。使用 API 方法、彩色多普勒、收缩期瓣口宽度（VCW）、有效反流口面积（PISA-EROA）和反流容积（PISA-RV）评估 MR。
API 方法在 89%的 MVP 患者中可行（分别为 68%、71%和 VCW 及 PISA 方法，p<.001）。MVP 中非全收缩期 MR 的 API 方法的观察者内和观察者间相关性分别为 0.989 和 0.995。对于整个 MVP-MR 人群，API 与 MR 严重程度的直接和间接测量均有显著相关性。基于 ROC 曲线，建议 API 截断值为 125 au 以识别 MVP 中的重度 MR，而 MR 持续时间/收缩时间比<100%（即非全收缩期 MVP-MR）可识别出非重度 MR（API<125）患者，而大多数全收缩期 MVP 则存在重度 MR（API>125）。最后，API 分析 MVP 中的收缩早期、中期和晚期 MR 显示出与全收缩期 MVP 相比，非全收缩期 MVP 的动力学不同。
API 方法是一种可行且可重复的 MVP-MR 分级方法。由于 API 方法考虑了整个收缩期内 MR 流量的时间变化，因此它在临床实践中可能具有附加价值。
