Pathophysiology, Diagnosis, and New Therapeutic Approaches for Ischemic Mitral Regurgitation

Prognostic value of mitral valve regurgitation in patients with heart failure with mildly reduced ejection fraction

BACKGROUND

Although mitral valve regurgitation (MR) is a common valvular heart disease in patients with heart failure (HF), there is a paucity of data on the characterization and outcomes of patients with HF with mildly reduced ejection fraction (HFmrEF) and concomitant MR.

METHODS

From 2016 to 2022, consecutive patients hospitalized with HFmrEF (i.e., left ventricular ejection fraction from 41% to 49% and signs and/or symptoms of HF) were retrospectively included at one institution. Patients with MR were compared with patients without MR. Further risk stratification was performed according to MR severity and etiology (i.e., primary vs. secondary MR). The primary end point was all-cause mortality at 30 months (median follow-up), and the key secondary end point was hospitalization for worsening HF.

RESULTS

Of 2181 patients hospitalized with HFmrEF, 59% presented with mild, 10% with moderate, and 2% with severe MR. MR was associated with increased all-cause mortality at 30 months (HR = 1.756; 95% CI 1.458-2.114; p = 0.001), with higher risk in more advanced stages. Furthermore, MR patients had higher risk of HF-related re-hospitalization at 30 months (HR = 1.560; 95% CI 1.172-2.076; p = 0.002). Even after multivariable adjustment, mild, moderate, and severe MR were still associated with all-cause mortality. Finally, the risk of all-cause mortality was lower in patients with secondary MR compared with patients with primary MR (HR = 0.592; 95% CI 0.366-0.956; p = 0.032).

CONCLUSION

MR is common in HFmrEF and independently associated with higher risk of all-cause mortality and HF hospitalization.

Mitral valve repair versus replacement in severe ischemic mitral regurgitation systematic review and meta-analysis

BACKGROUND AND AIM

Ischemic mitral regurgitation (IMR) is a serious consequence of coronary artery disease. The choice of the optimal surgical strategy remains debatable. The aim of the present meta-analysis is to compare the outcomes of mitral valve repair (RPR) versus replacement (RPL) regarding perioperative mortality, overall mortality, reoperation, recurrence of MR, and reverse remodeling after surgery.

METHODS

Electronic searches were performed using the searchable databases of Google Scholar, Pubmed, and Embase, and the search terms mitral valve, IMR, RPR, RPL, and coronary artery bypass grafting. The main outcomes of interest are perioperative mortality, overall mortality, reoperation, recurrence of MR, and reverse remodeling after surgery. Perioperative mortality was defined as death during the surgery or within 30 days after the operation.

RESULTS

There was a trend towards better perioperative survival in the RPR arm. However, the difference fell short of statistical significance [odds ratio (OR) (95% confidence interval [CI]): 0.66 (0.41-1.07), p = 0.09]. Patients submitted to RPR experienced a significantly higher MR recurrence rate when compared with their counterparts submitted to RPL [OR (95% CI): 16.8 (5.07-55.7, p = 0.00001)].

CONCLUSION

There is a trend towards lower perioperative mortality in RPR in comparison to RPL. On the other hand, RPL was associated with significantly lower recurrence rates.

Ischemic mitral regurgitation: when should one intervene?

PURPOSE OF REVIEW

Optimal timing of intervention for ischemic mitral regurgitation remains to be elucidated. This review summarizes the data on the management of ischemic mitral regurgitation, and their implications on current practice and future research.

RECENT FINDINGS

Mechanistically, ischemic mitral regurgitation can present as Type I, Type IIIb or mixed Type I and IIIb disease. Severity of mitral regurgitation is typically quantified with echocardiography, either transthoracic or transesophageal echocardiography, but may also be assessed via cardiac MRI. In patients with moderate ischemic mitral regurgitation, revascularization can lead to left ventricular reverse remodeling in some. In patients with severe ischemic mitral regurgitation, mitral valve replacement may be associated with fewer adverse events related to heart failure and cardiovascular readmissions, compared with valve repair, although reverse remodeling may be better in patients following successful mitral repair. Transcatheter edge-to-edge repair also further complements the treatment of ischemic mitral regurgitation.

SUMMARY

A tailored approach to patients should be considered for each patient presenting with ischemic mitral regurgitation.