Kubo Shunsuke, Nakamura Mamoo, Shiota Takahiro, Itabashi Yuji, Mizutani Yukiko, Nakajima Yoshifumi, Meemook Krissada, Hussaini Asma, Makar Moody, Siegel Robert J, Kar Saibal
From the Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (S. Kubo, M.N., T.S., Y.I., Y.M., Y.N., K.M., A.H., M.M., R.J.S., S. Kar); and Department of Cardiology, Kurashiki Central Hospital, Japan (S. Kubo).
Circ Cardiovasc Interv. 2017 Jul;10(7). doi: 10.1161/CIRCINTERVENTIONS.116.004909.
An increase of systolic forward flow was frequently observed after successful MitraClip implantation in patients with significant mitral regurgitation. However, the impact of systolic forward flow improvement on post-MitraClip outcomes remains unknown.
Study population included 160 patients who underwent successful MitraClip implantation. The systolic forward flow was noninvasively calculated as the forward stroke volume (FSV) at baseline before the MitraClip procedure and before discharge with pulse-wave Doppler using transthoracic echocardiography. The optimal threshold of discharge/baseline FSV ratio for 3-year all-cause death was assessed. The best cutoff ratio was 1.09 (9% FSV increase from baseline, =0.006). The FSV responders were defined as those with >9% increase of FSV from baseline (n=93). From discharge to 12-month follow-up, a significant reduction of LV end-diastolic and end-systolic volumes was observed in the responders, whereas no significant change was observed in the nonresponders. Furthermore, the proportion of New York Heart Association functional class III/IV was significantly lower in the responders at 12 months (2.9% versus 14.6%; =0.03). Among patients with estimated glomerular filtration rate <60 mL/min per 1.73 m2, estimated glomerular filtration rate was significantly improved at 12 months only in the responders. All-cause mortality at 3 years was significantly lower in the responders than in the nonresponders (17.6% versus 42.3%; =0.002). Multivariable logistic analysis identified higher baseline FSV, less mitral regurgitation severity, and functional mitral regurgitation as independent predictors of the nonresponders.
FSV increase after MitraClip implantation was associated with more favorable clinical and anatomic outcomes. Severity and pathogenesis of mitral regurgitation and pre-MitraClip FSV predicted postprocedural FSV response.
在重度二尖瓣反流患者成功植入MitraClip后，经常观察到收缩期前向血流增加。然而，收缩期前向血流改善对MitraClip术后结局的影响尚不清楚。
研究人群包括160例成功植入MitraClip的患者。在MitraClip手术前的基线以及出院前，使用经胸超声心动图通过脉冲波多普勒无创计算收缩期前向血流，即前向搏出量（FSV）。评估了3年全因死亡的出院/基线FSV比值的最佳阈值。最佳截断比值为1.09（FSV较基线增加9%，P=0.006）。FSV反应者定义为FSV较基线增加>9%的患者（n=93）。从出院到12个月随访，反应者的左心室舒张末期和收缩末期容积显著减少，而非反应者未观察到显著变化。此外，反应者在12个月时纽约心脏协会功能分级III/IV的比例显著更低（2.9%对14.6%；P=0.03）。在估算肾小球滤过率<60 mL/min per 1.73 m2的患者中，仅反应者在12个月时估算肾小球滤过率显著改善。反应者3年全因死亡率显著低于非反应者（17.6%对42.3%；P=0.002）。多变量逻辑分析确定较高的基线FSV、较轻的二尖瓣反流严重程度和功能性二尖瓣反流是非反应者的独立预测因素。
MitraClip植入后FSV增加与更有利的临床和解剖学结局相关。二尖瓣反流的严重程度和发病机制以及MitraClip术前FSV可预测术后FSV反应。
