Impact of Forward Stroke Volume Response on Clinical and Structural Outcomes After Percutaneous Mitral Valve Repair With MitraClip

Abstract

Background-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 postMitraClip outcomes remains unknown. Methods and Results-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, P=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%; P=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%; P=0.002). Multivariable logistic analysis identified higher baseline FSV, less mitral regurgitation severity, and functional mitral regurgitation as independent predictors of the nonresponders. Conclusions-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. (Circ Cardiovasc Interv. 2017;10:e004909.

Impact of Renal Congestion in Patients With Secondary Mitral Regurgitation After Mitral Transcatheter Edge-to-Edge Repair

“…18,19 Based on the COAPT trial, 20 MitraClip therapy is considered a favorable option for the treatment of heart failure, and is also expected to be a good option for renal congestion. The forward stroke volume is increased after TEER, 21 which should improve hemodynamics and result in improved renal congestion. Among the present patients who had a discontinuous IRVF pattern prior to MitraClip therapy, the majority demonstrated improvement in MR grade; however, only 30% showed an improvement to a continuous IRVF pattern following MitraClip therapy (Supplementary Figure).…”

Left ventricular outflow tract velocity-time integral improves outcome prediction in patients with secondary mitral regurgitation

“…In line with this hypothesis, LVOT-VTI showed the highest C-statistics for the prediction of cardiac death, while the calculation of an optimal prognostic cut-off (17 cm) allowed an accurate stratification of patient risk over the follow-up (Log rank 44.3, p < 0.001). Interestingly, in a sub-analysis of the EVEREST II trial [26], percutaneous edge-to-edge mitral valve repair was associated with a greater hemodynamic and clinical improvement in the patients with a lower baseline forward LV flow. Considering the retrospective nature of the present work, further well-designed prospective studies should clarify whether the integration of LVOT-VTI with other clinical and instrumental parameters, such as EROA and GLS, may optimize the selection of the patients with HF and functional MR which could benefit more from mitral valve intervention.…”

Can stress echocardiography identify patients who will benefit from percutaneous mitral valve repair?

“…Another study showed that an increase in stroke volume after MitraClip implantation (stroke volume at discharge divided by stroke volume at baseline, discharge/baseline ratio) was associated with a more favourable outcome. Further, patients with an increase in stroke volume after the MitraClip implantation had a significantly more severe MR at baseline and a significantly lower stroke volume at baseline [ 22 ].…”