Handgrip echocardiography predicts clinical outcomes in patients with ischemic mitral regurgitation

Abstract Background Mitral regurgitation (MR) is frequent in patients with ischemic heart disease and carries a dismal prognosis. Previous studies already demonstrated the prognostic benefit of bicycle exercise testing in patients with ischemic MR. Thus, current guidelines emphasize the role of exercise testing in patients with valvular heart disease. Isometric handgrip exercise resembles an alternative exercise intervention, that can also be performed in frail, comorbid patients. Until now, there are no data on the prognostic impact of handgrip echocardiography in heart failure patients with ischemic MR. Purpose To assess the prognostic benefit of isometric handgrip testing in heart failure patients with ischemic MR. Methods We prospectively enrolled patients with ischemic cardiomyopathy (left ventricular ejection fraction <50%) and at least mild MR that underwent echocardiography at rest and during handgrip exercise between January 2019 and September 2021. Patients were followed-up for one year to assess clinical outcomes. The combined endpoint included all-cause mortality, heart failure hospitalisation, ventricular assist device implantation (VAD), heart transplantation and mitral valve (MV) surgery/intervention. Results We included 133 patients (mean age was 75±10 years, 21% were female). Seventy patients (53%) presented with mild MR, while 54 patients had moderate MR (41%), and 9 patients (7%) showed severe MR at rest. Twenty-five patients (20%) with non-severe MR at rest, developed severe MR during handgrip exercise. One-year follow-up (median 321 (162-427) days) was complete in 128 patients (96%). Seventy-one patients (56%) experienced an adverse event: 13 patients (10%) died, 33 patients (26%) were re-admitted to hospital due to heart failure symptoms, 30 patients (24%) underwent MV transcatheter edge-to-edge repair, six patients (5%) received MV surgery, one patient (1%) underwent VAD implantation, and another three patients (4%) underwent heart transplantation. According to MR severity at rest, there was no difference in outcomes in patients with mild, moderate and severe MR (p=0.189). As expected, patients with severe MR at rest more often tended to undergo mitral valve surgery/interventions compared to the other groups (p=0.064). However, patients with non-severe MR at rest and exercise-induced severe MR presented with adverse outcomes similar to patients with severe MR at rest (p=0.005). Furthermore, patients with severe MR at rest and patients with dynamic severe MR underwent mitral valve surgery/interventions more frequently than patients with non-severe MR (p<0.001). Conclusion(s) In heart failure patients with ischemic MR, isometric handgrip testing unmasks severe MR in approximately every fifth patient with non-severe MR at rest. These patients showed similar clinical outcomes as compared to patients with severe MR already at rest. Thus, handgrip exercise testing might be a useful tool to guide further therapeutic decision making.