Mitral Regurgitation and Prognosis After Non-ST-Segment Elevation Myocardial Infarction in Very Old Patients

NSTEMI and Ischemic Mitral Regurgitation: Incidence and Long-Term Clinical Outcomes with Respect to Management Strategy

BACKGROUND

The optimal treatment for ischemic mitral regurgitation (IMR) in patients of non-ST elevation myocardial infarction (NSTEMI) is a debated topic.

OBJECTIVE

To evaluate the long term outcome on patients with NSTEMI and IMR, particularly emphasizing the comparison of treatments in those with moderate to severe MR.

METHODS

We enrolled patients with NSTEMI and classified non/trivial to mild regurgitation as insignificant IMR and moderate to severe regurgitation as significant IMR. Furthermore, patients with substantial IMR were assessed for long-term clinical outcomes with respect to different management strategies. A test was considered statistically significant based on the probability value p<0.05.

RESULTS

From a total of 4,189 patients of NSTEMI, significant IMR was found in 7.21% of patients. A significantly higher number of patients with death (1.21% vs. 13.24%, p<0.0001), cardiogenic shock (0.46% vs. 13.24%, p<0.0001) and heart failure (1.03% vs. 11.59%, p<0.0001) were found during hospitalization in patients with significant IMR. At a 2-year follow-up, a higher event rate was observed in the significant IMR group. Patients with significant IMR re-vascularized either by percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), or CABG+ mitral valve (MV) surgery showed substantial improvement in MR grade ( 32.65% vs. 6% vs. 16.98%, p<0.0001) and LVEF (27.55% vs. 1% vs. 1.89%, p<0.0001) at 1 year follow up and significantly improved outcomes were identified compared to refused revascularization and medical management group with (-5.10% vs. 15% vs. 13.21%, p=0.04) mortality, (-33.67% vs. 61% vs. 73.58%, p<0.0001) readmission, and (-15.31% vs. 27% vs. 33.96%, p=0.01) heart failure at 2 years follow up.

CONCLUSION

Higher mortality and admission rates were observed in patients with significant IMR compared to those with in-significant IMR. Notably, significant IMR patients who underwent PCI, CABG, or CABG+MV surgery showed improved outcomes compared to non-revascularized counterparts.

Update on surgical repair in functional mitral regurgitation

BACKGROUND

Functional mitral regurgitation (FMR) is common in patients with myocardial infarction or dilated cardiomyopathy, and portends a poor prognosis despite guideline-directed medical therapy (GDMT). Surgical or transcatheter mitral repair for FMR from recent randomized clinical trials showed disappointing or conflicting results.

AIMS

To provide an update on the role of surgical repair in the management of FMR.

MATERIALS AND METHODS

A literature search was conducted utilizing PubMed, Ovid, Web of Science, Embase, and Cochrane Library. The search terms included secondary/FMR, ischemic mitral regurgitation, mitral repair, mitral replacement, mitral annuloplasty, transcatheter mitral repair, and percutaneous mitral repair. Randomized clinical trials over the past decade were the particular focus of the current review.

RESULTS

Recent data underlined the complexity and poor prognosis of FMR. GDMT and cardiac resynchronization, when indicated, should always be applied. Accurate assessment of the interplay between ventricular geometry and mitral valve function is essential to differentiate proportionate FMR from the disproportionate subgroup, which could be helpful in selecting appropriate transcatheter intervention strategies. Surgical repair, most commonly performed with an undersized ring annuloplasty, remains controversial. Adjunctive valvular or subvalvular repair techniques are evolving and may produce improved results in selected FMR patients.

CONCLUSION

FMR resulted from complex valve-ventricular interaction and remodeling. Distinguishing proportionate FMR from disproportionate FMR is important in exploring their underlying mechanisms and to guide medical treatment with surgical or transcatheter interventions. Further studies are warranted to confirm the clinical benefit of appropriate surgical repair in selected FMR patients.