Impact of preoperative body mass index on long-term survival, quality of life, and functional outcomes after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension: Results from the UK National Cohort.

BACKGROUND

Previous studies have demonstrated the safety of pulmonary endarterectomy (PEA) across body mass index (BMI) strata. However, long-term survival and patient-reported outcome measures by BMI strata remain unknown. We examined the impact of preoperative BMI on long-term survival, QOL, and functional outcomes for patients undergoing PEA for chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

Retrospective review of 2,004 patients from the UK National Cohort between 2007 and 2021 undergoing PEA for CTEPH (mean pulmonary artery pressure >20 mm Hg and pulmonary vascular resistance >160 dynes). Patients were stratified into BMI<20, 20 to 29, 30 to 39, 40 to 49, and 50+. All-cause mortality was the primary outcome measure. Secondary outcome measures were 3- to 6-month postoperative hemodynamics, 6-minute walk distance (6MWD), New York Heart Association (NYHA) class, and Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) scores.

RESULTS

Hemodynamics and 6MWD at 3 to 6 months were similar across BMI strata. Patients with BMI 50+ reported the highest incidence of postoperative NYHA III/IV limitation (53.3%, p < 0.001) and the highest residual symptom burden by CAMPHOR (p < 0.001). Five-year survival was lowest in patients with BMI 50+ (70.2%) and BMI<20 (73.4%), while highest in BMI 30 to 39 (88.2%, p = 0.008). Ten-year Kaplan-Meier estimates predicted the lowest survival in BMI 50+ and BMI<20.

CONCLUSIONS

PEA remains safe and effective for all patients regardless of BMI. Despite similar hemodynamic outcomes, patients with BMI 50+ are at the greatest risk of long-term all-cause mortality, and patients with BMI 50+ experience residual symptomatic limitation.