CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 5, September/October 2022 AFRICA 245 The mean diameter of ITA measured under the light microscope was similar between the groups (1.52 ± 0.35 vs 1.56 ± 0.3 mm, p = 0.463). Under light microscope evaluation, there were more damaged endothelial samples in group A than in group B (p = 0.0037, odds ratio: 7.875, 95% CI: 1.96–31.68) (Table 2). In more than half of the patients in group A, the subendothelium of the ITA was dispersed and disrupted, and some patients had visible luminal evagination of the endothelium and subendothelium (Fig. 2). In comparison with the patients in group A, in 86.7% of patients in group B, the endothelium and sub-endothelium showed normal morphology (p = 0.029, odds ratio: 7.43, 95% CI: 1.23–45.01) (Fig. 3). No postoperative complications, such as re-exploration for bleeding, renal failure, peri-operative detectable myocardial infarction, mediastinitis and stroke, were observed in either group. Six months after the operation, echocardiographic evaluation showed no new regional wall abnormality or worsening of left ventricular function, and exercise stress tests were not found to have any positive signs of ischaemia. One year after the operation, 10 patients with damaged ITA samples were followed up for angiography for ITA visualisation. Coronary angiography showed no ITA stenosis or occlusion in any of these patients (Fig. 4). No deaths or cardiac events occurred during this period. Discussion Using the ITA is the gold standard for grafting the left anterior descending artery to the anterior cardiac wall during CABG.6 The improved outcome using the ITA is due to its superior long-term patency.7 The ITA has a discontinuous internal elastic lamina and a relatively thin media with multiple elastic laminae and the absence of a significant muscular component, which explains its reduced tendency for spasm and the development Table 2. ITA harvesting time, diameter, free flow and endothelial injury rate Variables Group A (n = 15) Group B (n = 15) p-value Harvest time (min) 21.2 ± 7.5 10.3 ± 8.1 < 0.001* Diameter (mm) 1.52 ± 0.35 1.56 ± 0.30 0.463* Free flow (ml/min) 43.6 ± 48.7 51.7 ± 45.0 0.762* Length of ITA (cm) 20.3 ± 2.7 19.1 ± 3.4 0.298* Damaged ITA sample, n (%) 14 (47) 3 (10) 0.0037** Injured ITA patient, n (%) 8 (53.3) 2 (13.3) 0.029** *Student’s t-test, **Fisher’s exact test. Fig II. Histopathological view of ITA sample harvested with 20W Damaged endothelium (arrow) and subendothelial layer (arrow head) (Haematoxylin and Eosin Staining. Bar: 20 µm.) Fig. 2. Histopathological view of ITA sample harvested with 20W. Damaged endothelium (arrow) and subendothelial layer (arrow head). (Haematoxyin and eosin staining. Bar: 20 μm.) Fig III. Histopathological view of ITA sample harvested with 40W Normal morphology of vessel with partially damaged endothelium (arrow) and subendothelial layer (arrow head) (Haematoxylin and Eosin Staining. Bar: 20 µm.) Fig. 3. Histopathological view of ITA sa ple harvested with 40W. Normal morphology of vessel with partially damaged endothelium (arrow) and subendothelial layer (arrow head). (Haematoxyin and eosin staining. Bar: 20 μm.)
RkJQdWJsaXNoZXIy NDIzNzc=