Impact of Frailty in Patients Undergoing Minimally Invasive Mitral Valve Surgery

Objective: Psoas muscle size is a reliable marker of sarcopenia and frailty that correlates with adverse outcomes after cardiac surgery. However, its use in mitral and minimally invasive cardiac surgery is lacking. We sought to determine whether frailty, as measured by psoas muscle index, increases surgical risk for minimally invasive mitral valve surgery. Methods: Patients undergoing isolated minimally invasive mitral surgery via right minithoracotomy were identified. Patients who underwent maze, tricuspid intervention, and those who were emergent were excluded. Total psoas muscle area was calculated using the average cross-sectional area at the L3 vertebra on computed tomography scan and indexed to body surface area. Sarcopenia was defined as <25th gender-specific percentile. Patients were stratified by sarcopenia status and outcomes compared. Results: Of 287 total patients, 192 patients met inclusion criteria. Sarcopenic patients were 6 years older (66 vs 60 years, P = 0.01), had lower preoperative albumin levels (4.0 vs 4.3 g/dL, P < 0.001), and had higher Society of Thoracic Surgeons risk of morbidity/mortality (13.1% vs 9.0%, P = 0.003). Operative major morbidity or mortality was 6.4% versus 5.5% (P = 0.824), while the 1-year mortality rate was 2.1% versus 0% (P = 0.08). After risk adjustment, psoas index did not predict operative morbidity or mortality. However, sarcopenia was associated with higher odds of readmission (odds ratio = 0.74, P = 0.02). Conclusions: Contrary to other cardiac operations, for patients undergoing isolated minimally invasive mitral valve surgery, sarcopenia was not associated with increased perioperative risk except for higher readmission rates. Minimally invasive surgical approaches should be strongly considered as the approach of choice in frail patients.