Discussion
Intramyocardial course of a coronary artery is an inborn anomaly and defined as the intramural location of the artery through the myocardium. [8,9] According to pathological serious the prevalence of intramyocardial course ranges from 5% to 86% [10,11] and from 0.5% to 33% in angiographic series [13-14]. E A Vanker et al, observed IMLAD in 293 patients undergoing CABG out of 1349 and reported the prevalence of IMLAD as 21.7%. [1] In our study, the prevalence of the IMLAD in patients undergoing CABG was 13%.
Thanks to the advantages of revealing the properties of coronary artery obstructive lesions, conventional CAG remains the gold standard imaging procedure for the diagnoses of coronary artery diseases.[15,16] In some of the CAG procedures, LAD is seen diving into the myocardium at an acute angle and coming back to the epicardial layer following a variable length of course composing a “wide-U” imaging(Cicekcioglu sign), which is seen more clearly on the right anterior oblique position. This LAD depression sign was observed to have a correlation with the intraoperative detection of IMLAD.
In case of an IMLAD as a target artery to be bypassed, there may be compelling situations for the surgeon in terms of distal anastomosing process. There are several options for locating IMLAD during surgery. One is “Blind dissection” which is applied by dissecting myocardium in the epicardial region of the anterior interventricular groove. This technique may cause a severe damage to the subepicardial myocardium resulting with the perforation of the ventricles. [17-19] Another solution is using the great cardiac vein, which usually has a course in the epicardial fat and stays more superficially than the artery, as a leading point. Using a coronary probe, which is inserted to the artery from the distal visible part, is another technique. However, the risk of perforating the coronary artery may cause serious intraoperative morbidities. [20] Performing doppler ultrasound with a color doppler microprobe, intraoperative fluorescence angiography and cineangiography are other less invasive but respectively more expensive techniques for locating IMLAD. [21-24]