The Obesity Paradox in Chronic Total Occlusion Percutaneous Coronary Intervention: Contemporary Outcomes Across Body Mass Index Categories

This study examined the impact of body mass index (BMI) on procedural and long-term outcomes following percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). While obesity is an established cardiovascular risk factor, an “obesity paradox” has been observed in various cardiac interventions, but contemporary data in CTO PCI are limited. We analyzed 503 consecutive CTO PCI procedures in 453 patients at our institution between January 2018 and December 2023, stratified by BMI into obese (≥30 kg/m², n = 213, 42.4%), overweight (25-29.9 kg/m², n = 194, 38.6%), and healthy weight (18.5-24.9 kg/m², n = 96, 19.1%). The primary endpoint was a composite of in-stent restenosis requiring revascularization, heart failure hospitalization, myocardial infarction, and stroke at a median follow-up of 704 days. Obese patients were younger (median 64.0 vs 67.0 vs 68.5 years, p < 0.001) and less frequently current smokers (8.5% vs 10.3% vs 19.8%, p = 0.012). Technical and procedural success were lower in obese patients (79.8% vs 75.8% vs 92.7% and 79.3% vs 75.3% vs 92.7%, respectively; p = 0.002), while radiation exposure increased significantly with BMI (median air kerma: 2385 vs 1688 vs 1126 mGy, p < 0.001). At follow-up, the composite endpoint occurred in 16.5% vs 12.3% vs 16.3% (p = 0.492), with similar all-cause mortality (3.9% vs 6.4% vs 7.0%, p = 0.425). On multivariable analysis, male sex was associated with lower risk of adverse outcomes (HR 0.53, 95% CI 0.30 to 0.95), while baseline heart failure was associated with higher risk (HR 1.83, 95% CI 1.04 to 3.25). In conclusion, despite significantly lower technical and procedural success rates and higher radiation exposure, obese patients undergoing CTO PCI had comparable long-term outcomes to healthy weight patients, supporting the obesity paradox. These findings suggest that BMI alone should not preclude CTO PCI but mandate enhanced radiation safety protocols and careful patient counseling regarding procedural success expectations.