Long Term Prognosis of Intramural Course of Coronary Arteries in Patients with Hypertrophic Cardiomyopathy Assessed by Coronary CT Angiography

Background: The prognostic value of an intramural course of the coronary arteries detected by coronary CTA in patients with HCM is not well-known.

Objective: To evaluate in patients with hypertrophic cardiomyopathy (HCM), who were referred for cardiac computed tomography angiography (CTA) whether an intramural course of the coronary arteries is associated with a worse clinical outcome compared to HCM patients without an intramural course of their coronaries.

Methods: The study population consisted of 92 patients with HCM who were referred for coronary CTA and who did not have obstructive CAD. During follow-up, the occurrence of unstable angina pectoris that required hospitalization, myocardial infarction, and all-cause mortality was evaluated (i.e. adverse cardiac events).

Results: Using coronary CTA, 57 patients (62%) had an intramural course of their coronary arteries. Patients with HCM were followed for over 5.5 ± 3.5 years. The composite of adverse cardiac events occurred in 17/57 (29.8%) patients with an intramural course and in 11/35 (31.4%) patients without an intramural course (P = 0.87). The event rate of unstable angina pectoris requiring hospitalization (28.1% vs. 22.9%), myocardial infarction (1.8% vs. 8.6%), and all case mortality (0.0% vs. 0.0%) was similar in patients with and without an intramural course.

Conclusion: Intramural course of coronary arteries in patients with HCM was frequently observed by coronary CTA, but it was not associated with worse cardiovascular clinical outcomes.