Resumen de Histological alterations of the human myocardium during minimally invasive direct coronary artery bypass operation
K. Kaidoglou, A. Alvanou, A. Bisbos, Th. Anagnostopoulos
To study the ischaemia caused to myocardial cells during the Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) procedure, ten patients underwent surgical revascularization of the anterior descending artery using the MIDCAB technique. During the anastomosis, the left anterior descending (LAD) was snared with two sutures 4-0 prolene. The time of ischaemia was 13-22 min (mean 16.4 min). Three biopsies were taken from the anteroapical part of the left ventricle: a) Prior to the ischaemia b) At the end of the ischaemic period c) 25 minutes after blood flow had been restored. The degree of cellular and perivascular damage was studied by electron microscopy. Simultaneously, an electrocardiogram (ECG) was performed and the biochemical markers of myocardial ischaemia were measured. There were no deaths or myocardial infarctions. Slight ischaemic changes were found in all tissue samples before occlusion of the LAD. A semiquantitative analysis showed that a large percentage of myocytes (83.5-90%) in all phases were normal or only slight changes. A few myocytes (3-6%) were severely or irreversibly damaged. The morphometric analysis of mitochondrial oedema revealed no statistically significant differences. In conclusion, the MIDCAB technique can be applied for the surgical revascularization of the LAD without significant ischaemic changes to the myocardial cells.
