Direct Implantation of Transcatheter Valve in Mitral Annular Calcification: A Multi-Center Study

Abstract

BACKGROUNDMitral valve replacement (MVR) in the setting of severe annular calcification (MAC) is associated with high morbidity and mortality. Direct surgical implantation of a transcatheter heart valve (THV) through a trans-atrial approach is a strategy to mitigate surgical risk. This study reports the peri-operative and 1-year outcomes of MVR using a THV in patients with severe circumferential MAC at three Canadian centers. METHODSCharts were reviewed between 1/1/2018 and 30/9/2023 to identify patients with severe circumferential MAC who had undergone direct implantation of a THV. Primary outcomes were 30-day mortality, debilitating stroke, and 1-year mortality. Secondary outcomes included left ventricular outflow tract obstruction (LVOTO), degree of PVL, transvalvular mean pressure gradient, and length of stay. RESULTSTwenty-two patients at the three centres underwent direct implantation of a THV. Nineteen were female with mean age 70.41±9.33 years. A THV was successfully implanted in all patients. There were two deaths at 30-days. Four died from non-cardiac causes at 1-year, and 1 patient had a post-operative stroke. Seventeen (77%) patients had none/trace paravalvular leak, 4 had mild PVL, and one patient had mild-moderate PVL. Mean trans-valvular gradient was 4.42±4.40. There were no cases of LVOTO. CONCLUSIONSDirect deployment of a THV in patients with severe MAC may be a reasonable option. Thirty-day and 1-year mortality rates of 9% and 18%, respectively, suggest that this approach should be reserved for high-risk patients who are not able to undergo conventional strategies.