Comparison of sharp dissection, electrocautery, and ultrasonic activated scalpel with regard to endothelial damage, preparation time, and postoperative bleeding during radial artery harvesting

Abstract Objective: To examine the effects of classical technique, electrocautery, and ultrasonic dissection on endothelial integrity, function, and preparation time for harvesting the radial artery (RA) during coronary artery bypass grafting (CABG). Methods: Forty-five patients who underwent isolated CABG and whose RA was suitable for use were studied and divided into three groups: Group 1, classical method (using sharp dissection); Group 2, electrocautery; and Group 3, ultrasonic cautery. Levels of prostacyclin and nitric oxide derivatives were examined biochemically; vascular cell adhesion molecule 1 (VCAM-1) and endothelial nitric oxide synthetase (eNOS) values were assessed using immunohistochemical staining. RA preparation time, RA length/harvesting time ratio, and drainage amounts at the site of RA removal were compared. Results: Differences in RA preparation time (Group 1: 25±6 min, Group 2: 18±3 min, Group 3: 16±3 min, P<0.001) and length/harvesting time ratio (Group 1: 0.76±0.19 cm/min, Group 2: 0.98±0.16 cm/min, Group 3: 1.13±0.09 cm/min, P<0.001) were statistically significant among the groups. Levels of prostacyclin and nitric oxide derivatives were not statistically significant different, VCAM-1 and eNOS expressions were observed to be similar among the groups, and endothelial damage was detected in only one patient per group. Conclusion: Use of ultrasonic cautery during RA preparation considerably reduces the preparation time and postoperative drainage amount. However, the superiority of one method over the others could not be demonstrated when the presence of endothelial damage with both biochemical and histopathological evaluations was considered.

Comparison of Sharp Dissection, Electrocautery, and Ultrasonic Activated Scalpel with Regard to Endothelial Damage, Preparation Time, and Postoperative Bleeding During Radial Artery Harvesting.

OBJECTIVE: To examine the effects of classical technique, electrocautery, and ultrasonic dissection on endothelial integrity, function, and preparation time for harvesting the radial artery (RA) during coronary artery bypass grafting (CABG). METHODS: Forty-five patients who underwent isolated CABG and whose RA was suitable for use were studied and divided into three groups: Group 1, classical method (using sharp dissection); Group 2, electrocautery; and Group 3, ultrasonic cautery. Levels of prostacyclin and nitric oxide derivatives were examined biochemically; vascular cell adhesion molecule 1 (VCAM-1) and endothelial nitric oxide synthetase (eNOS) values were assessed using immunohistochemical staining. RA preparation time, RA length/harvesting time ratio, and drainage amounts at the site of RA removal were compared. RESULTS: Differences in RA preparation time (Group 1: 25±6 min, Group 2: 18±3 min, Group 3: 16±3 min, P<0.001) and length/harvesting time ratio (Group 1: 0.76±0.19 cm/min, Group 2: 0.98±0.16 cm/min, Group 3: 1.13±0.09 cm/min, P<0.001) were statistically significant among the groups. Levels of prostacyclin and nitric oxide derivatives were not statistically significant different, VCAM-1 and eNOS expressions were observed to be similar among the groups, and endothelial damage was detected in only one patient per group. CONCLUSION: Use of ultrasonic cautery during RA preparation considerably reduces the preparation time and postoperative drainage amount. However, the superiority of one method over the others could not be demonstrated when the presence of endothelial damage with both biochemical and histopathological evaluations was considered.

Frequency of development of aspirin resistance in the early postoperative period and inadequate inhibition of thromboxane A2 production after coronary artery bypass surgery.

BACKGROUND: This study aims to investigate the frequency of the development of aspirin resistance, whether or not this resistance was reversible, and to evaluate the efficiency of the mechanism of incomplete inhibition of thromboxane A2 in development of aspirin resistance in the early postoperative period in patients who had undergone coronary artery bypass grafting. METHODS: Eighty patients (55 males, 25 females; mean age 63.1±9.2 years; range 51 to 75 years) who underwent coronary artery bypass grafting between February 2009 and March 2010 at our clinic were prospectively evaluated. Venous blood samples were collected from all patients and evaluated by a platelet function analyzer in the preoperative period and on postoperative days 7 and 15. Aspirin resistance diagnosis was defined as collagen-epinephrine closure time less than 186 seconds. The urine levels of 11-dehidro thromboxane B2 were also measured on postoperative day one. RESULTS: Aspirin resistance was found in 23 patients (28.75%) in the preoperative period, in 31 patients (38.75%) on the postoperative seventh day and in 25 patients (31.25%) on the postoperative 15th day. The urine levels of 11-dehidro thromboxane B2 in patients with aspirin resistance on the postoperative seventh day were significantly higher than those in patients without aspirin resistance (p<0.001). The mean aortic cross-clamping time (p=0.003) and cardiopulmonary bypass time (p=0.029) in the patients with aspirin resistance on the postoperative seventh day were significantly higher than those in patients without aspirin resistance. CONCLUSION: The results of this study suggest that aspirin resistance develops within the first seven days after coronary artery bypass grafting and is highly reversible, and that the mechanism of inadequate inhibition of thromboxane A2 by aspirin has a role in the development of aspirin resistance in the early postoperative period.

Evaluation of heart rate variability in patients with coronary artery ectasia and coronary artery disease.

OBJECTIVE: The present study compared heart rate variability (HRV) parameters in patients with coronary artery ectasia (CAE) and coronary artery disease (CAD). METHODS: The study population consisted of 60 consecutive patients with CAE (14 women; mean age 51.63±7.44 years), 60 consecutive patients with CA (15 women; mean age 53.67±9.31 years), and 59 healthy individuals (13 women; mean age 52.85±8.19 years). Electrocardiograms, 24-hour Holter analyses, and routine biochemical tests were performed, and clinical characteristics were evaluated. Coronary angiography images were analyzed. Time-domain HRV parameters, including the standard deviation (SD) of normal-to-normal intervals (SDNN) and the root mean square of difference in successive normal-to-normal intervals (RMSSD) were evaluated, as were frequency-domain HRV parameters including low-frequency (LF), very low-frequency (VLF), high-frequency (HF), the proportion derived by dividing low- and high-frequency (LF/HF), and total power (TP). RESULTS: SDNN was lower in both the CAE and CAD groups, compared to the healthy group (140.85±44.21, 96.51±31.28, and 181.05±48.67, respectively). A significant difference in RMSSD values among the groups was determined (p=0.004). Significantly decreased VLF and HF values were found in the CAE group, compared with the healthy group (VLF p<0.001; HF, p=0.007). TP, VLF, and HF values were significantly lower (p<0.001, p<0.001, and p<0.001, respectively), but LF and LF/HF values were significantly higher (p<0.001 for both) in the CAD group than in the healthy group. TP values were significantly higher (p<0.001), and LF and LF/HF values were lower in the CAE group, compared with the CAD group (p<0.001 for both). CONCLUSION: A decrease in vagal modulation or an increase in sympathetic activity of cardiac function, assessed by HRV analysis, is worse in patients with CAD than in patients with CAE.

Does high serum uric acid level cause aspirin resistance?

In patients with coronary artery disease (CAD), though aspirin inhibits platelet activation and reduces atherothrombotic complications, it does not always sufficiently inhibit platelet function, thereby causing a clinical situation known as aspirin resistance. As hyperuricemia activates platelet turnover, aspirin resistance may be specifically induced by increased serum uric acid (SUA) levels. In this study, we thus investigated the association between SUA level and aspirin resistance in patients with CAD. We analyzed 245 consecutive patients with stable angina pectoris (SAP) who in coronary angiography showed more than 50% occlusion in a major coronary artery. According to aspirin resistance, two groups were formed: the aspirin resistance group (Group 1) and the aspirin-sensitive group (Group 2). Compared with those of Group 2, patients with aspirin resistance exhibited significantly higher white blood cell counts, neutrophil counts, neutrophil-to-lymphocyte ratios, SUA levels, high-sensitivity C-reactive protein levels, and fasting blood glucose levels. After multivariate analysis, a high level of SUA emerged as an independent predictor of aspirin resistance. The receiver-operating characteristic analysis provided a cutoff value of 6.45 mg/dl for SUA to predict aspirin resistance with 79% sensitivity and 65% specificity. Hyperuricemia may cause aspirin resistance in patients with CAD and high SUA levels may indicate aspirin-resistant patients. Such levels should thus recommend avoiding heart attack and stroke by adjusting aspirin dosage.