Myocardial bridges: A prospective forensic autopsy study

Abstract

Introduction When the coronary artery, located subepicardially, submerges into the myocardium and appears again subepicardially after a short intramural course, it represents an embedded coronary artery, while the part of the myocardium above is a myocardial bridge. Objective We investigated the frequency of the embedded left coronary artery (LAD) in the autopsy material considering the descending branch of the LAD to be the most important one in the nourishment of the myocardium and myocardial bridges to be the most frequent in its area, as well as clinically important. Methods A prospective autopsy study of 975 cases was performed, including both, natural (21.33%) and violent (78.67%) deaths. The sample consisted of 74.56% males and 25.44% females. In order to discover myocardyal bridges and their characteristics, the hearts were examined by both transverse cuts and longitudinal openings of the LAD. Results Myocardial bridge was found in 78 cases (8.00%), more commonly in males (9.35%) than females (4.03%). The average length of the myocardial bridge was 21.85±16.10mm and thickness 3.744±1.48 mm. The common localization of the myocardial bridge was the proximal half of the LAD (89.74%). The upper part of the artery, proximal to the bridge, was a common site of atherosclerotic changes. Myocardial bridge was found in 12.50% of natural deaths, but in 13.38% out of all cases of sudden cardiac deaths. Conclusion Therefore, the presence of the myocardial bridge by itself is not predominant, but it is certainly a contributing factor to a sudden cardiac death.

Uvod 'Poniruća koronarna arterija' je pojam koji se odnosi na slučaj kada koronarna arterija - inače lokalizovana subepikardno - ponire u miokard i ponovo se pojavljuje subepikardno, posle kratkog puta kroz mišić, pri čemu se mišić iznad nje naziva 'miokardni most'. Cilj rada Istraživali smo učestalost poniruće descendentne grane leve koronarne arterije u autopsijskom materijalu imajući u vidu da je ona najvažnija u ishrani srčanog mišića, da najčešće ponire u srčani mišić i da je vrlo značajna i s kliničkog aspekta. Metode rada Urađena je prospektivna autopsijska studija 975 slučajeva prirodnih (21,33%) i nasilnih smrti (78,67%). Uzorak je obuhvatio 74,56% osoba muškog i 25,44% ženskog pola. Radi otkrivanja miokardnog mosta i analize njegovih osobenosti, nishodna grana leve koronarne arterije otvarana je uzdužnim i poprečnim obdukcionim rezovima. Rezultati Miokardni most je utvrđen u 78 slučajeva (8,00%), češće kod muškaraca (9,35%) nego kod žena (4,03%). Prosečna dužina miokardnog mosta bila je 21,85±16,10 mm, a debljina 3,744±1,48 mm. Najčešća lokalizacija miokardnog mosta bila je u predelu proksimalne polovine descendentne grane leve koronarne arterije (89,74%), a aterosklerotske promene su najčešće ustanovljene ushodno od miokardnog mosta. Miokardni most je postojao u 12,50% slučajeva prirodnih smrti, odnosno u 13,38% slučajeva tzv. naprasnih srčanih smrti. Zaključak Postojanje miokardnog mosta nije predominantni činilac za pojavu naprasne srčane smrti, ali je njegovo postojanje faktor rizika za njen nastanak.