Multidetector-row CT coronary angiographic finding of myocardial bridging

Multiple myocardial bridging in the elderly: A rare case

Myocardial bridging occurs when a segment of major epicardial coronary artery courses intramurally through myocardium, commonly involving the left anterior descending. However, myocardial bridging involving coronary arteries other than left anterior descending is less-common and rarely reported, especially in the elderly population. We report a rare case of multiple myocardial bridging involving the left anterior descending, first obtuse marginal, and ramus intermedius in a 68-year-old Asian female. We also briefly discuss the imaging evaluation and pathophysiology of myocardial ischemia in myocardial bridging. This is the second reported case of myocardial bridging involving such combination, and to our knowledge, the first for elderly patient.

Myocardial bridging of the left anterior descending coronary artery: depiction rate and morphologic features by dual-source CT coronary angiography

Objective

To evaluate the depiction rate and morphologic features of myocardial bridging (MB) of the left anterior descending coronary artery (LAD) using dual-source CT (DSCT).

Materials and Methods

CT scans from a total of 1,353 patients who underwent DSCT were reviewed retrospectively for LAD-MB. Seventy-eight patients were excluded due to poor image quality or poor enhancement of the coronary artery. The length and depth of the MB were analyzed and classified as superficial or deep with respect to the depth (≤ 1 or > 1 mm) of the LAD tunneled segment. Superficial MB was subdivided into complete or incomplete types according to full or partial encasement of the myocardium.

Results

Of the 1,275 patients included in this study, 557 cases of MB were found from 536 patients (42%). Superficial MB was observed in 368 of 557 (66%) cases, and deep MB was seen in 189 of 557 (34%) cases. Superficial MB showed 2 types: complete (128 of 368, 35%) and incomplete (240 of 368, 65%). The mean length of a tunneled segment for superficial MB was 16.4 ± 8.6 mm. The mean length and depth of a tunneled segment for deep MB were 27.6 ± 12.8 mm and 3.0 ± 1.4 mm, respectively. The incidence of atherosclerotic plaques in a 2-cm-long segment proximal to MB was 16%.

Conclusion

The depiction rate of LAD-MB using DSCT in a large series of patients was 42%, with two-thirds of MB segments being the superficial type.