Comparison of the Apoptotic Effects of Topically Applied Papaverine, Diltiazem, and Nitroprusside to Internal Thoracic Artery.

OBJECTIVE: To detect and to compare the apoptotic effects of intraoperatively topically applied diltiazem, papaverine, and nitroprusside. METHODS: Internal thoracic artery segments of ten patients were obtained during coronary bypass grafting surgery. Each internal thoracic artery segment was divided into four pieces and immersed into four different solutions containing separately saline (Group S), diltiazem (Group D), papaverine (Group P), and nitroprusside (Group N). Each segment was examined with both hematoxylin-eosin and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method in order to determine and quantify apoptosis. RESULTS: Apoptotic cells were counted in 50 microscopic areas of each segment. No significant difference was observed among the four groups according to hematoxylin-eosin staining. However, the TUNEL method revealed a significant increase in mean apoptotic cells in the diltiazem group when compared with the other three groups (Group S=4.25±1.4; Group D=13.31±2.8; Group N=9.48±2.09; Group P=10.75±2.37). The differences between groups were significant (P=0.0001). No difference was observed between the samples of the diabetic and non-diabetic patients in any of the study groups. CONCLUSION: The benefit of topically applied vasodilator drugs must outweigh the potential adverse effects. In terms of apoptosis, diltiazem was found to have the most deleterious effects on internal thoracic artery graft segments. Of the analyzed medical agents, nitroprusside was found to have the least apoptotic activity, followed by papaverine. Diabetes did not have significant effect on the occurrence of apoptosis in left internal thoracic artery grafts.

Comparison of the apoptotic effects of topically applied papaverine, diltiazem, and nitroprusside to internal thoracic artery

Abstract Objective: To detect and to compare the apoptotic effects of intraoperatively topically applied diltiazem, papaverine, and nitroprusside. Methods: Internal thoracic artery segments of ten patients were obtained during coronary bypass grafting surgery. Each internal thoracic artery segment was divided into four pieces and immersed into four different solutions containing separately saline (Group S), diltiazem (Group D), papaverine (Group P), and nitroprusside (Group N). Each segment was examined with both hematoxylin-eosin and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method in order to determine and quantify apoptosis. Results: Apoptotic cells were counted in 50 microscopic areas of each segment. No significant difference was observed among the four groups according to hematoxylin-eosin staining. However, the TUNEL method revealed a significant increase in mean apoptotic cells in the diltiazem group when compared with the other three groups (Group S=4.25±1.4; Group D=13.31±2.8; Group N=9.48±2.09; Group P=10.75±2.37). The differences between groups were significant (P=0.0001). No difference was observed between the samples of the diabetic and non-diabetic patients in any of the study groups. Conclusion: The benefit of topically applied vasodilator drugs must outweigh the potential adverse effects. In terms of apoptosis, diltiazem was found to have the most deleterious effects on internal thoracic artery graft segments. Of the analyzed medical agents, nitroprusside was found to have the least apoptotic activity, followed by papaverine. Diabetes did not have significant effect on the occurrence of apoptosis in left internal thoracic artery grafts.

An old friend is still at work: 34-year-old well functioning Starr-Edwards aortic prosthesis without anticoagulation.

The Starr-Edwards caged-ball valve prosthesis is the beginning mark of the valve replacement era, and was used widely in many centers worldwide in the past decades. Despite long term results with this prosthesis have been reported with satisfactory hemodynamic performance, only a few cases have been reported exceeded 30 years of durability. We report the case of a patient with a 34-year-old well-functioning Starr-Edwards ball prosthesis in aortic position using neither antiaggregant nor anticoagulant therapies.

Protective effects of resveratrol in ischemia-reperfusion injury of skeletal muscle: A clinically relevant animal model for lower extremity ischemia.

Ischemia and reperfusion injury of the skeletal muscle is a common and serious condition observed in patients admitting to peripheral vascular surgery, interventional radiology and cardiology departments. Resveratrol (RVT) being a strong natural antioxidant is found in deal of red wine and Mediterranean diet. In the present study, male Spraque-Dawley rats were randomized into two groups of equal size. The first group was the control group, and these rats were administered with tap water with a gastric tube for fourteen consecutive days once daily. According to the same protocol, the rats in the second group were treated with tap water containing 20 mg/kg RVT. All the rats in the two groups were subjected to acute hind limb ischemia through clamping of the abdominal aorta for 120 min. Following this procedure, 60 minutes of reperfusion was applied by reestablishing blood flow in both iliac arteries. Ischemic damage in the skeletal muscle tissue was assessed by measuring myoglobin, lactate dehydrogenase, creatinine phosphokinase, aspartate transaminase enzymes in venous blood samples obtained at the end of the reperfusion period. Oxidative stress caused by reperfusion was determined by measuring MDA, carbonyl and protein sulphydryl levels in quadriceps muscle tissue retrieved at the end of the experiment. In Group II rats, all the measured ischemic enzymes and the markers of oxidative stress reflected robust anti-ischemic properties obtained by RVT administration. The data from both groups revealed statistically significant protection against acute skeletal muscle ischemia and reperfusion injury in Group II rats, compared to Group I. As a major dietary flavonoid RVT can protect the skeletal muscle tissue against global ischemia and reperfusion injury because of its strong antioxidant and cytoprotective properties.

Does radial artery harvesting for coronary revascularization cause neurological injury in the forearm and hand?

OBJECTIVE: Radial artery (RA) is now used widely as a conduit of choice in coronary artery bypass grafting. Although RA removal is considered safe in the presence of adequate collateral arterial supply, there is still a considerable suspicion on the functional status of the forearm and hand. However, a neurological dysfunction may occur owing to either surgical trauma or ischemic neuropathy. This study was aimed to investigate the functional outcome of the donor forearm nerves of the patients who underwent coronary artery bypass grafting surgery with RA conduits. METHODS: A consecutive series of 50 patients who underwent coronary artery bypass graft surgery with one or two RA grafts were investigated in the study. Motor and sensory functions of donor forearm nerves were measured by ENMG studies, pre- and postoperatively at the third week and sixth month of the operation. The conduction velocities, distal latencies and amplitudes of action potentials for motor and sensorial conductions of radial, ulnar and median nerves were measured in each ENMG examination. Neurologic status of the donor forearm and hand was assessed by the same neurologist who performed a detailed neurologic physical examination and ENMG studies. Results were statistically compared using one-way ANOVA test. RESULTS: The incidence of any neurologic symptoms was 32% in early postoperative period. All reported neurologic complaints were associated with sensory conduction deceleration in ENMG investigations of related nerves. In postoperative assessment, median nerve sensory-motor, and ulnar nerve motor conduction records were slightly lower than the preoperative values, but no statistical difference was observed. Pre- and postoperative radial nerve motor and sensory conduction records were statistically similar (P>0.05). CONCLUSIONS: We advocate that removal of RA does not lead to any major neurologic hand complications in the presence of adequate collateral arterial blood supply. ENMG studies confirmed minimal conduction alterations with no statistical significance, even if neurologic symptoms were stated.

Trimetazidine improves recovery during reperfusion in isolated rat hearts after prolonged ischemia.

OBJECTIVE: Trimetazidine (TMZ) is a cellular anti-ischemic agent, which has been studied in clinical and experimental investigations, and was shown to have protective affects against myocardial ischemia and reperfusion injury. The major objective of this study was to investigate the cardio-protective effects of trimetazidine in prolonged global ischemia subjected Langendorff perfused rat hearts. METHODS: Twenty rats (Male Sprague-Dawley) were divided into two study groups. In Group 2 (n=10) TMZ was given by intra-gastric gavage (3 mg/kg BW twice daily for 5 days) prior to operation and was added to the Krebbs-Henseleit perfusate to create a 10-6 M solution to perfuse the isolated rat hearts. Group 1 (n=10) reserved as control group and received saline at the same time period. All hearts were paced at 300 beats/min. After a 20-minute of stabilization period, hearts in both groups were arrested for 120 minutes with crystalloid cardioplegia. After ischemic period, the hearts were then reperfused for 30 minutes. Hemodynamic measurements from left ventricular latex balloon, coronary flow, and creatine kinase (CK-MB) and troponin T (cTnT) levels determined from the coronary effluent were analyzed at the end of stabilization and at every 10-min intervals during reperfusion, and results were compared between two groups. RESULTS: No significant differences were observed in all entered hemodynamic and biochemical parameters between two groups at the end of the stabilization. However, peak systolic pressure, end diastolic pressure and +dP/dt values reflected improved mechanical myocardial recovery in Group 2 hearts after prolonged ischemia. Besides coronary flow measurements were higher in Group 2 compared with Group 1. CK-MB and cTnT levels indicated to less enzymatic damage in trimetazidine treated hearts during reperfusion. CONCLUSION: In conclusion, both pre-treatment and treatment protocols with TMZ reduce the myocardial damage caused by global ischemia following reperfusion. We could speculate that this beneficial effect of trimetazidine might be useful in open-heart surgery patients, who were subjected to global myocardial ischemia.

Improved myocardial function with the addition of pinacidil to custadiol.

BACKGROUND: This study investigates the efficacy of pinacidil, an adenosine triphosphate-sensitive potassium (KATP) channel opening agent, added to custadiol solution on myocardial protection during deep hypothermia and prolonged global ischemia on isolated rat hearts. METHODS: After 20 minutes of stabilization, 24 rats were divided into two groups. In group I (n=12), hearts were arrested with cold (4 degrees C) custadiol solution containing 50 micromol/L of pinacidil and subsequently dipped into the same solution for 120 minutes at 4 degrees C. Group I hearts were perfused with low-flow pinacidil-custadiol (PC) solution during the ischemic period. Group II (n=12) hearts, after the stabilization period, were arrested with cold custadiol solution only, then subsequently dipped and perfused with the same solution for 120 minutes at 4 degrees C. All hearts were reperfused with Krebb's-Henseleit solution at 37 degrees C for 60 minutes. Hemodynamic parameters (peak systolic pressure, end diastolic pressure, maximum rate of increase of left ventricular pressure [+dP/dt], ischemic contracture, and coronary sinus flow) were recorded at the end of the stabilization period and at 10-minute intervals during the reperfusion period. Biochemical data (creatine kinase [CK-MB] washout and troponin I [cTnI] levels) were compared between the two groups. RESULTS: There was no significant difference in any hemodynamic or biochemical parameters between the two groups during the stabilization period. The peak systolic pressure, +dP/dt, ischemic contraction amplitude, and coronary flow values were significantly higher in group I ( P<0.05) compared with group II during reperfusion. End diastolic pressures as well as CK-MB and cTnI levels were lower in the pinacidil-treated group, which is consistent with improved functional recovery during the reperfusion period. CONCLUSION: The addition of pinacidil to the preservation solution, custadiol, improves myocardial recovery after deep hypothermia and prolongs ischemia.