The current study is the first to demonstrate that Transcatheter mitral valve repair using the MitraClip (developed by Abbott Vascular, Menlo Park, California) is beneficial compared to surgical repair in a multivariable-adjusted analysis in hospitalizations for patients with advanced chronic kidney disease hospitalizations.
We hypothesized that the use of MitraClip is associated with lower complications rates, lesser length of hospitalizations stay and lower cost as compared to surgical repair in advanced kidney disease hospitalizations.
Why is this study important?
Major clinical trials excluded all those patients with severe renal insufficiency from their study. Given the paucity of data on the effect of renal dysfunction on patients undergoing TMVR, we sought to evaluate the impact of baseline advanced kidney disease on the outcomes of “real-world” patients treated with TMVR as compared with conventional SMVR utilizing a large, national database.
Percutaneous edge-to-edge transcatheter mitral valve repair (TMVR) has emerged as a novel and effective treatment option for patients with severe mitral regurgitation (MR) who have a high surgical risk. The EVEREST II trial demonstrated similar improvements in clinical outcomes with inferior clinical efficacy.
Mitral regurgitation is a common valve disorder, often accompanied by multiple co-morbidities, including renal impairment. This study demonstrated that patients age is much higher when undergoing percutaneous repair as compared to surgery (72.4 vs 61.7 years, p <0.001). All complications were observed significantly lower after adjusted for several variables. Although limitations are present in this study, this study is hypothesis generative.
How was this study conducted?
This study utilized the nation’s largest, publicly available national inpatient (NIS) sample database. The NIS is developed by the Healthcare Cost and Utilization Project and sponsored by the Agency for Healthcare Research and Quality. Hospitalizations with chronic kidney disease stage IV, V and patients with an end-stage renal disease were included.
Among patients with advanced kidney disease studied nationally, in-hospital morbidity and mortality were lower after TMVR compared to SMVR. TMVR was associated with significantly reduced length of stay and hospitalization costs when compared with SMVR in CKD patients. Further clinical studies are necessary for patients with severe mitral regurgitation and advanced kidney disease to guide the optimal treatment strategy.
The intervention world is still growing and moving towards transcatheter mitral valve replacement. Future work may involve but not limited to: analyzing the impact of advanced CKD using estimated glomerular filtration rate and see if the results are same, predictors of mortality in patients with advanced CKD underwent mitral valve repair to better understand this problem.
Additionally, the EVEREST II trial only demonstrated inferior clinical efficacy with MitraClip. It is yet to be examined if transcatheter mitral valve replacement can further improve clinical efficacy as well.
These findings are described in the article Comparison of Transcatheter Mitral Valve Repair Versus Surgical Mitral Valve Repair in Patients With Advanced Kidney Disease (from the National Inpatient Sample), recently published in The American Journal of Cardiology.