Pulmonary Hypertension and Operative Risk in Mitral Valve and Coronary Surgery.

INTRODUCTION: Pulmonary hypertension (PHT) is a known risk factor for coronary artery bypass grafting (CABG), though less well understood for valve operations. We hypothesized PHT is associated with lower risk during mitral valve operations compared to CABG.

METHODS: Patients undergoing isolated mitral valve or CABG operations (2011-2019) in a regional Society of Thoracic Surgeons (STS) database were stratified by pulmonary artery systolic pressure (PASP). The association of PASP by procedure type was assessed by hierarchical regression modeling, adjusting for STS predicted risk scores.

RESULTS: Of the 2542 mitral and 11,059 CABG patients, the mitral population had higher mean STS risk of mortality (3.6% versus 2.4%, P < 0.0001) and median PASP (42 mmHg versus 32 mmHg, P < 0.0001). PASP was independently associated with operative mortality and major morbidity in both mitral and CABG patients. However, for mitral patients a 10-mmHg increase in PASP was associated with lower odds of morbidity (odds ratio: 1.06 versus 1.13), mortality (odds ratio: 1.11 versus 1.18) and intensive care unit time (4.3 versus 7.6 h) compared with CABG patients (interaction terms P < 0.0001). Among mitral patients, median PASP was higher in stenotic versus regurgitant disease (57 mmHg versus 40 mmHg, P < 0.0001). However, there was no differential association of PASP on morbidity or mortality (interaction terms P > 0.05).

CONCLUSIONS: Although mitral surgery patients tend to have higher preoperative pulmonary artery pressures, PHT was associated with a lower risk for mitral outcomes compared with CABG. Further research on the management and optimization of patients with PHT perioperatively is needed to improve care for these patients.