Acute mitral regurgitation: The role of transcatheter edge-to-edge repair
Keywords
Acute mitral regurgitation
Transcatheter treatment
Myocardial infarction
Endocarditis
Flail leaflet
Abbreviations
M-TEER
mitral transcatheter edge-to-edge repair
TEER
transcatheter edge-to-edge repair
1. Introduction
Untreated acute mitral regurgitation (MR) presents as a severe, rapidly progressive condition associated with significant mortality. Clinically, patients often manifest acute pulmonary edema, as consequence of the abrupt volume and pressure overload imposed on the non-compliant left atrium. This haemodynamic perturbation results in a marked reduction in forward cardiac output, as a substantial proportion of left ventricular stroke volume is diverted into the left atrium, thereby compounding haemodynamic instability
[1].
Acute MR can arise from a spectrum of etiologies, including a) acute myocardial infarction, leading to papillary muscle rupture or asymmetrical leaflet tethering secondary to regional wall motion abnormalities; b) infective endocarditis (IE); c) spontaneous chordal rupture; d) iatrogenic leaflet or chordal injury; and e) Takotsubo cardiomyopathy. Precise etiological identification is paramount for guiding optimal therapeutic strategies.
Medical management of acute mitral regurgitation (MR) prioritizes the alleviation of pulmonary congestion via intravenous diuretic administration and, if necessary, mechanical ventilation. Afterload reduction with vasodilator agents, such as nitroprusside or nitro-glycerine, can mitigate regurgitant volume; however, their application is frequently constrained by systemic hypotension. Vasoactive agents (e.g., norepinephrine or dopamine) may be required to maintain haemodynamic stability. In cases of progression to cardiogenic shock (CS), mechanical circulatory support (MCS), including intra-aortic balloon pump (IABP), transaortic microaxial pump, or venoarterial extracorporeal membrane oxygenation (VA-ECMO), may be indicated. Nevertheless, mitral valve (MV) intervention remains crucial, particularly in emergent scenarios. Surgical repair or replacement has historically been the standard of care for acute MR, however, the advancements in transcatheter edge-to-edge repair (TEER) therapies,
Table 1, provide alternative treatment strategies, especially for patients deemed high-risk for conventional surgery,
Fig. 1 [2]. (See
Central illustration.)