The Association Between Myocardial Bridging and Hypertrophic Cardiomyopathy and Their Implications on Percutaneous Coronary Intervention Outcomes: A Retrospective Study

Hypertrophic cardiomyopathy (HCM) is a complex cardiac disorder, often associated with adverse outcomes, including sudden cardiac death. Myocardial bridging (MB), where a coronary artery segment traverses intramurally within the myocardium, complicates coronary blood flow dynamics. This retrospective study investigates the relationship between MB and HCM and their impact on percutaneous coronary intervention (PCI) outcomes. Data from the 2019 National Inpatient Sample (NIS), representing 20% of U.S. hospitalizations, was utilized. Patients with both HCM and MB undergoing PCI were identified and analyzed. The study assessed inpatient outcomes, including mortality, length of stay, hospital cost, and post-PCI complications (atrial fibrillation, acute kidney injury, bleeding, coronary dissection). Patients with HCM and MB exhibited distinct demographics. The study did not find significant associations between HCM/MB and inpatient mortality, length of stay, or hospital cost. However, HCM patients had a higher incidence of atrial fibrillation and acute kidney injury post-PCI (aOR 2.33, 95% CI 1.46 to 3.71, p ≤ 0.001). MB was linked to increased occurrences of acute heart failure (aOR 0.62, 95% CI 0.42-0.92, p = 0.02) and post-PCI bleeding (aOR 4.88, 95% CI 1.17-20.2, p = 0.03). This nationwide study reveals unique demographic profiles for HCM and MB patients. Notably, HCM patients face higher risks of post-PCI complications, including atrial fibrillation and acute kidney injury. These findings provide fresh insights into the MB-HCM relationship and its implications for PCI outcomes. They emphasize the need for tailored interventions and improved patient management in cases involving both HCM and MB.