Intraoperative changes and prognostic implications of pulmonary hypertension in patients with hypertrophic obstructive cardiomyopathy undergoing surgical septal myectomy

Objectives: Patients with hypertrophic cardiomyopathy often have concomitant pulmonary hypertension, which has a negative prognostic effect in patients undergoing myectomy. Our objective was to investigate the effect of myectomy on pulmonary artery pressure obtained via Swan-Ganz catheter and characterize how changes in pulmonary artery systolic pressure may indicate outcomes in these patients. Methods: We performed a single-center retrospective analysis of 271 patients with recordings of intraoperative pulmonary artery pressures during surgical myectomy. We analyzed primary composite outcomes as 30-day or in-hospital major cardiopulmonary adverse events. Results: There was a 5.17% adverse event rate. Patients with adverse events were older, were more likely to be female, had chronic obstructive pulmonary disease, and had longer cardiopulmonary bypass times. Some 35.7% of those with adverse events had moderate to severe pulmonary hypertension (pulmonary artery systolic pressure ≥50 mm Hg) on postbypass stress test, compared with 4.3% of those without adverse events (P < .001). Further, 21.4% of patients with adverse events had pulmonary artery systolic pressure 50 mm Hg or greater at the end of surgery, compared with 1.9% of patients without adverse events (P < .001). The pulmonary artery systolic pressure decrease after surgery in those without adverse events was on average 5 mm Hg more than in those with adverse events. Conclusions: Postoperative pulmonary hypertension was associated with a higher rate of adverse cardiopulmonary events. This may influence the decision to use Swan-Ganz catheters in patients undergoing septal myectomy in monitoring pulmonary artery pressures to better risk stratify and manage these patients postoperatively.