Myocardial bridging: Role of dobutamine stress echo vs. CT coronary angiography

Background: Myocardial bridge (MB), a congenital anomaly primarily impacting the left anterior descending artery, is linked to symptoms comprising chest pain, reduced blood flow, and heart attacks. Whereas frequently seen in patients with unexplained angina and no major coronary blockages, its identification and treatment pose significant challenges. Aim: The study aimed to identify noninvasive Myocardial Bridging through CTCA and correlate bridge criteria with strain values from dobutamine stress echocardiography to differentiate between significant and non-significant Myocardial Bridging. Material and Methods: The study evaluated 120 patients, categorizing them into four distinct groups: Superficial Myocardial Bridging (MB), Deep MB, Coronary Artery Disease (CAD), and a Control group. Patients were assessed for resting electrocardiograms, CT-CA and Dobutamine stress echocardiography. Results: The LVEF was lowest in CAD group (52.90±2.71) and highest in controls (45.46±3.42). Strain parameters (GLS, GCS, GAS, GRS) showed significant differences across groups, with both MB groups differing from CAD. During dobutamine stress echocardiography, LVEF was lowest in the superficial MB group (57.69±5.13) and highest in the deep MB group (63.80±4.59), with significant differences noted. CT angiography revealed 60% of MBs in the proximal LAD. Caliber attenuation occurred in 80% of the deep group versus 8.6% in the superficial group. Conclusion: Deep myocardial bridges exhibit distinct echocardiographic and strain patterns compared to superficial MBs and CAD patients, suggesting varying clinical implications.