Effects of papaverine and carbon dioxide alone or in combination on the blood flow of internal thoracic artery.

OBJECTIVE: The internal thoracic artery is frequently used as an arterial graft for coronary bypass. Spasms of internal thoracic artery may contribute to early myocardial ischemia. To prevent vasospasm and increase the blood flow, some vasodilatory agents (such as carbon dioxide or papaverine) are used. The aim of the study was to evaluate the combined effects of carbon dioxide and papaverine versus either alone on the blood flow of the internal thoracic artery. METHODS: One hundred patients undergoing coronary artery bypass grafting (28 women and 72 men) with similar characteristics were randomly divided into four groups. We used the classic technique without any vasodilatory management before surgery in group 1, papaverine injection into the endothoracic fascia in group 2, and carbodissection technique in groups 3 and 4. Initial free flows of the internal thoracic arteries were measured after cutting of the vessel. After the first measurement, the ITA pedicles were washed with papaverine solution and wrapped with gauze in the first and fourth groups. Blood flow measurements were repeated 15 minutes later in all groups. RESULTS: When vasodilatory management was applied during excision, the blood flows were significantly increased relative to group 1. The mean blood flows reached a significantly higher level in groups 1, 2, 3, and 4 at the second measurements. In groups 2 and 3, the increase at the first measurements compared to the first group's level was continuously high, but no additional increase was observed between the first and second measurements. In groups 1 and 4, regardless of whether a previous vasodilatory management was present, the increases measured at repeated measurements were significant versus each group's first measurements (P < .05). CONCLUSIONS: Vasodilatory management, such as injection of papaverine into endothoracic fascia or carbon dioxide insufflation applied during excision, increased the free blood flows of internal thoracic artery pedicles. Exogenously applied papaverine produces an additional and continuous vasodilatation regardless of whether a vasodilatory intervention was previously applied.

Investigation of Chlamydia pneumoniae DNA, chlamydial lipopolisaccharide antigens, and Helicobacter pylori DNA in atherosclerotic plaques of patients with aortoiliac occlusive disease.

BACKGROUND AND INTRODUCTION: It has been suggested that chronic infections may have a role in both the initiation and progression of atherosclerosis. While the majority of available data are focused on coronary artery disease, our aim was to investigate the presence of Chlamydia pneumoniae and Helicobacter pylori in samples from aortoiliac occlusive disease. METHODS: Aorta-iliac atherectomy specimens were collected under sterile conditions from 21 patients (19 male, 2 female) undergoing surgery for aortoiliac occlusive disease. Seventeen macroscopically healthy vessels (12 internal mammary arteries, 3 radial arteries, prepared for coronary artery bypass graft, and 2 traumatic artery specimens, one of which was a superficial femoral artery and the other was a radial artery) were used as control. Blood samples for serological assays were obtained immediately before surgery. The polymerase chain reaction (PCR) was employed to search for H. pylori and C. pneumoniae DNA in atherosclerotic plaques and healthy vessel samples. Group-specific chlamydial lipopolysaccharide (LPS) antigens in atherosclerotic plaques and in healthy vessel samples and serum IgG antibodies to chlamydial LPS were determined by using a commercially available enzyme-linked immunosorbent assay (ELISA). Antibodies to H. pylori were also tested in all cases by means of an in-house ELISA. RESULTS: Chlamydial LPS and DNA were detected in 6 of 21 (28.57%) atherosclerotic lesions using ELISA or PCR, respectively. There was no evidence of H. pylori DNA in any plaque specimens. All cases in which C. pneumoniae DNA was positive were also seropositive for antichlamydial LPS. Neither C. pneumoniae DNA nor antigen nor H. pylori DNA was found in the macroscopically healthy samples. CONCLUSION: Our results suggest that C. pneumoniae but not, as proposed, H. pylori may be involved in the pathogenesis of aortoiliac atherosclerosis.

Cardioprotective effect of cold-blood cardioplegia enriched with N-acetylcysteine during coronary artery bypass grafting.

BACKGROUND: Cold-blood cardioplegia is a well-known method in coronary artery bypass graft surgery, and several authors have used various agents in the enrichment of cold-blood cardioplegia to decrease ischemia-reperfusion injury seen during surgery. N-acetylcysteine, which can increase glutathione levels, is one of the agents added to cardioplegic solutions to decrease myocardial injury. This study was planned to assess the efficiency of N-acetylcysteine-enriched cold-blood cardioplegia on early reperfusion injury in patients with ischemic heart disease undergoing coronary artery bypass grafting, using measurements of cardiac troponin I and malondialdehyde release. METHODS: Thirty patients (11 women and 19 men) with left ventricular ejection fraction greater than 0.40 scheduled for coronary artery bypass grafting were randomly divided into two groups. We used cold-blood cardioplegia enriched with N-acetylcysteine (50 mg per kilogram of body weight) in the first group and cold-blood cardioplegia alone in the second group. Hemodynamic variables and clinical properties of the patients were preoperatively and postoperatively evaluated. Enzyme releases were measured in the early hours after the operation. RESULTS: In the N-acetylcysteine-enriched group cardiac troponin I levels were lower than in the N-acetylcysteine-free group, and this difference was statistically significant. Cardiac troponin I levels increased in both groups in the 6th and 12th hours postoperatively, but there was a statistically significant difference between the two groups. Malondialdehyde levels were significantly higher in the N-acetylcysteine-free group after the 6th, 12th, 24th, and 48th hours postoperatively when compared with the N-acetylcysteine-enriched group. CONCLUSIONS: N-acetylcysteine-supplemented cold-blood cardioplegia minimizes myocardial injury in the early hours after and during the cardiac surgery.

The contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods.

Perioperative spasm of internal mammary artery is a common experience in coronary artery bypass grafting. Many techniques were described of harvesting the internal mammary artery to prevent vasospasm. We investigated the comparison of the contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods. Patients were divided into two groups depending on the harvesting technique. In the first and second groups arteries were harvested by classical and carbon dioxide insufflation techniques, respectively. In both groups, endothelial function of arteries was assessed by precontracting the rings with phenylephrine (10(-5)M) and dilatating them by cumulative acetylcholine (10(-8) to 10(-5)M) concentrations. Cumulative concentration-response curves for phenylephrine (10(-8) to 10(-4)M), noradrenaline (10(-9) to 10(-4)M), and 5-hydroxytryptamine (10(-9) to 10(-4)M) were obtained in all groups. Endothelial integrity of arteries were histopathologically evaluated. In both groups, acetylcholine caused concentration-dependent relaxations in rings precontracted with phenylephrine (10(-5)M). In arteries harvested by carbon dioxide insufflation technique, acetylcholine caused significantly higher relaxations compared to the rings obtained by classical technique (p<0.05). In all rings of study groups, phenylephrine, noradrenaline and 5-hydroxytryptamine caused concentration-dependent contractions. There was not any significant difference in concentration-dependent responses of these contracting pharmacological agents between the groups. Histopathological evaluation revealed no major arterial damage in both groups. Carbon dioxide insufflation technique does seem not only to protect the integrity of the endothelium and the whole vessel, but also prevent the possible vasospasm of the internal mammary artery segments.