[Determinants and prognosis of ischemic mitral regurgitation]
D Messika-Zeitoun1, S F Yiu, F Grigioni
1Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic and Mayo Foundation, Rochester, 200, First Street S.W., Rochester, 55905 MN, USA.
Abstract:
Ischemic mitral regurgitation (IMR) is mitral regurgitation (MR) due to complications of coronary artery disease. Two mechanisms can be individualized. Acute MR secondary to ruptured papillary muscle is a rare but often fatal complication of myocardial infarction. We focus on functional MR, much more common, which occurs without any intrinsic valve disease. It was often underrated because of low murmur intensity but is observed between 15 and 20% after a myocardial infarction. The presence and degree of the regurgitation are related to local left ventricular remodeling. The apical and posterior displacement of papillary muscles leads to excess valvular tenting which in turn, in association with loss of systolic annular contraction, determines the severity of the regurgitation. IMR presence is associated with an excess mortality. The mortality risk is directly related to the degree of the regurgitation and a regurgitant volume > or = 30 ml or an effective regurgitant orifice > or = 20 mm2 define a high-risk group. In current clinical practice, IMR is mainly corrected with ring annuloplasty. However, this technique does not correct local alterations of left ventricular remodeling and its benefits on long-term outcome remains to be demonstrated.
Insights
Ischemic mitral regurgitation (IMR), a complication of coronary artery disease, often occurs after myocardial infarction. Its severity relates to left ventricular remodeling, and high-risk IMR is linked to increased mortality.
Area of Science:
- Cardiology
- Cardiac Surgery
- Biomedical Engineering
Context:
- Ischemic mitral regurgitation (IMR) is a significant complication of coronary artery disease (CAD).
- Functional IMR, distinct from acute rupture, arises from left ventricular remodeling post-myocardial infarction (MI), affecting 15-20% of patients.
- This condition is often underestimated due to subtle murmur intensity but carries prognostic implications.
Purpose:
- To elucidate the mechanisms and clinical significance of functional ischemic mitral regurgitation.
- To highlight the relationship between left ventricular remodeling and IMR severity.
- To discuss current treatment strategies and their limitations.
Summary:
- Functional IMR results from apical and posterior papillary muscle displacement and loss of systolic annular contraction, leading to excessive valvular tenting.
- The degree of regurgitation, quantified by regurgitant volume (≥30 ml) or effective regurgitant orifice (≥20 mm2), defines a high-risk group with excess mortality.
- Current management often involves ring annuloplasty, which may not address underlying ventricular remodeling, questioning its long-term efficacy.
Impact:
- IMR significantly increases mortality risk, directly correlated with regurgitation severity.
- Identifying high-risk patients is crucial for guiding therapeutic decisions.
- Further research is needed to develop treatments that address the underlying ventricular remodeling for improved long-term outcomes in IMR.
More Related Videos
Related Concept Videos
01:20Mitral Regurgitation I: Introduction
01:23Mitral Regurgitation II: Clinical Features and Diagnostic Tests
01:25Mitral Regurgitation III: Medical Management
01:28Mitral Regurgitation IV: Nursing Management
01:22Mitral Stenosis I: Introduction
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests