Correspondence between left ventricular 17 myocardial segments and coronary anatomy obtained by multi-detector computed tomography: an ex vivo contribution

The aim of this study was to investigate the correspondence between the coronary arterial anatomy and the supplied myocardium based on the proposed American Heart Association (AHA) 17-segment model. Six human cadaveric hearts without signs of infarct were selectively injected with colored contrasted gelatin in the three major coronary arteries. After injection, the hearts were scanned by computed tomography (64-detector scanner LightSpeed VCT, GE Healthcare) with a collimation of 64 x 0.625 mm. Reconstructed image data were analyzed in order to evaluate the blood supply of each myocardial segment. Coronary artery territory varies due to anatomy variations. Left anterior descending coronary artery (LAD) was the main vessel responsible for the myocardium blood supply in 11 segments. LAD contributed to the blood supply of all apical segments. Left circumflex (LCx) was the main coronary artery for the infero-anterior wall. Right coronary artery (RCA) contributed in all hearts for the blood supply of infero-septal segments. There was an important overlap between LAD and RCA territories at the infero-septal region and between LAD and LCx territories at the antero-lateral region. In our experiment, LAD territory was larger than the AHA-proposed 17-segment model. The most specific segments were located at the anterior wall and supplied exclusively by LAD. No specific segment could be exclusively attributed to RCA or to LCx. Sometimes, LCx can be the most important artery for the blood supply of the inferior wall even if the origin of the posterior descending artery is the RCA.