[Myocardial bridge: morphological factors which influence symptoms].

Introduction: Myocardial bridge is a frequently detected congenital coronary anomaly which is kept benign. It is unique because it can cause a dynamic compression during systole.

Objective: In this article, we focus on the detection and evaluation of morphological parameters that can determine the symptomatic bridges.

Method: We summarize the invasive and noninvasive modalities regarding this topic. We also present our retrospective research when we studied the morphological features of the left anterior descendent bridges with coronarography which led to angina pectoris. We compared the prognosis of patients where only myocardial bridge was found to those where atherosclerosis also had been presented.

Results: Intravascular ultrasound can be adapted for the visualization of myocardial bridge and for measuring the severity of compression. Intracoronary Doppler- and fractional flow reserve allow the appreciation of functional significance. Stress echocardiography is the most used non-invasive imaging modality in this field. According to our results, the group where only myocardial bridge was presented has more severe morphological features. The shortening of the tunneled segment was more expressed. The mortality during long term (appr. 10 years) follow-up was low. Meanwhile, our results have demonstrated that none of the morphological parameters influence mortality.

Conclusion: There is an essential discrepancy between the phenomenon's high prevalence, the good prognosis, and the numerous case reports where the authors report about severe complications. Today we possess those invasive and non-invasive techniques which can help us to design prospective trials clarify the morphological features' functional significance. Orv Hetil. 2023; 164(14): 563-570.