Related Experiment Videos
Myocardial bridges: morphological and functional aspects
A G Ferreira1, S E Trotter, B König
1Department of Internal Medicine, Faculty of Medicine, University of State of Pará, Belém, Brazil.
Insights
Myocardial bridges were found in over half of hearts studied. Deep bridges, unlike superficial ones, may twist the left anterior descending artery, potentially causing ischemia.
Area of Science:
- Cardiovascular Anatomy
- Pathology
Background:
- Myocardial bridges are congenital anomalies where a segment of cardiac muscle traverses the epicardium.
- Their precise anatomical arrangement and potential clinical significance remain areas of investigation.
Purpose of the Study:
- To investigate the anatomical characteristics and classification of myocardial bridges.
- To assess the relationship between myocardial bridge morphology and potential hemodynamic compromise.
Main Methods:
- A necropsy study was conducted on 90 human hearts.
- Detailed dissection and morphological analysis of identified myocardial bridges were performed using magnification.
Main Results:
- Myocardial bridges were identified in 55.6% of the hearts, with the left anterior descending artery being most frequently involved.
- Two distinct types of myocardial bridges were observed: superficial and deep.
- Deep myocardial bridges, originating from the right ventricular apex, were found to surround the left anterior descending coronary artery.
Conclusions:
- Superficial myocardial bridges appear to have minimal impact on arterial constriction during systole.
- Deep myocardial bridges, due to their anatomical relationship, may cause torsional forces on the left anterior descending coronary artery.
- This twisting could compromise diastolic blood flow, potentially leading to myocardial ischemia.
Objective:
To assess the arrangement of myocardial bridges.
Design:
A necropsy study of 90 consecutive hearts (56 male, 34 female).
Results:
Myocardial bridges, either single or multiple, were seen in 50 (55.6%) of the 90 hearts. The left anterior descending artery was the most commonly affected artery. Thirty five of the 50 hearts which contained in total 41 muscle bridges were dissected further with a magnifying glass. Two different types of muscle bridges could be identified. Thirty one of these 41 myocardial bridges were superficial, crossing the artery transversely towards the apex of the heart at an acute angle or perpendicularly. The remaining 10 myocardial bridges crossed the left anterior descending coronary artery and surrounded it by a muscle bundle that arose from the right ventricular apical trabeculae and crossed the artery transversely, obliquely, or helically before terminating in the interventricular septum.
Conclusions:
The superficial type of myocardial bridge does not seem to constrict the artery during systole but the deep muscle bridges, by virtue of their relation with the left anterior descending coronary artery, could twist the vessel and thus compromise its diastolic flow. This may result in ischaemia.