Prevalence and characteristics of intramural coronary artery in hypertrophic obstructive cardiomyopathy: a coronary computed tomography and invasive angiography study.

BACKGROUND

The prevalence and morphologic characteristics of intramural coronary artery (ICA) in patients with hypertrophic obstructive cardiomyopathy (HOCM) have yet to be fully illuminated. Our study aimed to investigate the prevalence and morphologic characteristics of ICA in patients with HOCM using coronary computed tomography (CT) angiography and invasive coronary angiography.

METHODS

Patients with a diagnosis of HOCM who were admitted for selective myectomy in Fuwai Hospital were prospectively enrolled between September 2015 and June 2019. Both preoperative coronary CT and invasive angiography were scheduled for all participants.

RESULTS

Coronary CT angiography detected ICA in 106 (23.3%) out of 455 patients. Dynamic compression of coronary arteries was observed in 87 patients (19.1%) by invasive coronary angiography. We found ICA covered with complete myocardial encasement in 98 patients (92.5%), with deep myocardial bridging (MB) observed most frequently (P=0.005). All patients with dynamic compression of coronary arteries had ICA. Dynamic luminal reduction ≥50% was present in 77 (16.9%) of the study participants. Pearson's correlation analysis revealed that the length and degree of dynamic compression were significantly related with MB length and depth (Pearson's correlation r=0.241, 0.581, 0.316, and 0.209; P=0.014, <0.001, 0.002, and 0.032, respectively).

CONCLUSIONS

Patients with HOCM commonly present with ICA and it can be visualized well by coronary CT angiography. Deep or extensive MB is more likely to produce coronary artery dynamic compression. Preoperative identification of this congenital coronary artery variant may be helpful for surgical planning.