Perivascular nitric oxide delivery to saphenous vein grafts prevents graft stenosis after coronary artery bypass grafting: a novel sheep model.

OBJECTIVES: Graft stenosis is a major complication of coronary artery bypass grafting with autologous saphenous vein grafts. Nitric oxide (NO) is believed to prevent this phenomenon. We studied the effect of perivascular application of an NO donor on the degree of stenosis of such grafts in an ovine model. METHODS: Twenty white Iranian ewes were randomized to coronary artery bypass grafting using autologous saphenous vein grafts with application of an elastomer gel containing diethylenetriamine NO adduct in 0.9% sodium chloride solution around the grafted vessel (intervention group) or with the gel containing the saline solution alone (controls). Graft vessels were studied after 1 year using spot angiography and histological examination. RESULTS: The mean degree of stenosis was significantly lower in the intervention group than in the controls as found by histology (92.3 ± 5.5 vs. 80.9 ± 8.3%; p = 0.004). Although the difference in the angiographic score was not significant, the mean score was still lower in the intervention group (9.5 ± 11.3 vs. 12.0 ± 11.8). CONCLUSIONS: Perivascular application of an NO donor was, at least histologically, effective in reducing graft stenosis in our ovine model. This can be a step toward the development of drug-eluting coronary artery bypass grafts.

Cardiac and great vessel involvement in "Behcet's disease".

Behcet's disease is a multisystem disorder and classified as "vasculitic syndrome with a wide variety of clinical manifestations." Cardiac involvement is very rare but can occur with different presentations including: pericarditis, cardiomyopathy, endocarditis, endomyocardial fibrosis, intracavitary thrombosis, and coronary artery disease. Great vessel involvement is more common. Recurrent Phlebitis, commonly involving large vessels (superior vena cava, inferior vena cava, hepatic veins) and cerebral veins are the sole presentation in this regard. Arterial involvement is expressed by aneurysm or pseudoaneurysmal formation. Due to the wide variety of cardiovascular manifestations and the resulting high mortality, cardiac surgeons should be familiar with this disease. In this paper we review the articles and introduce our four cases presenting with aneurysm of ascending aorta with free aortic insufficiency, aneurysm of descending aorta, pulmonary artery aneurysm, and pseudoaneurysm of aortic arch.

Superficial and deep sternal wound infection after more than 9000 coronary artery bypass graft (CABG): incidence, risk factors and mortality.

BACKGROUND: Sternal wound infection (SWI) is an uncommon but potentially life-threatening complication of cardiac surgery. Predisposing factors for SWI are multiple with varied frequencies in different studies. The purpose of this study was to assess the incidence, risk factors, and mortality of SWI after coronary artery bypass grafting (CABG) at Tehran Heart Center. METHODS: This study prospectively evaluated multiple risk factors for SWI in 9201 patients who underwent CABG at Tehran Heart Center between January 2002 and February 2006. Cases of SWI were confirmed based on the criteria of the Centers for Disease Control and Prevention. Deep SWI (bone and mediastinitis) was categorized according to the Oakley classification. RESULTS: In the study period, 9201 CABGs were performed with a total SWI rate of 0.47 percent (44 cases) and deep SWI of 0.22 percent (21 cases). Perioperative (in-hospital) mortality was 9.1% for total SWI and about 14% for deep SWI versus 1.1% for non-SWI CABG patients. Female gender, preoperative hypertension, high functional class, diabetes mellitus, obesity, prolonged intubation time (more than 48 h), and re-exploration for bleeding were significant risk factors for developing SWI (p = 0.05) in univariate analysis. In multivariate analysis, hypertension (OR = 10.7), re-exploration (OR = 13.4), and female gender (OR = 2.7) were identified as significant predictors of SWI (p < 0.05 for all). The rate of SWI was relatively similar in 3 groups of prophylactic antibiotic regimen (Cefazolin, Cefazolin + Gentamycin and Cefazolin + Amikacin: 0.5%, 0.5%, and 0.34% respectively). CONCLUSION: Rarely reported previously, the two risk factors of hypertension and the female gender were significant risk factors in our study. Conversely, some other risk factors such as cigarette smoking and age mentioned as significant in other reports were not significant in our study. Further studies are needed for better documentation.

Post-traumatic chordae rupture of tricuspid valve.

Blunt injury to the chest can affect any one or all components of the chest wall and thoracic cavity. The clinical presentation of patients with blunt chest trauma varies widely and ranges from minor reports of pain to florid shock. Traumatic tricuspid valve regurgitation is a rare cardiovascular complication of blunt chest trauma. Tricuspid valve regurgitation is usually begotten by disorders that cause the right ventricle to enlarge. Diagnosis is made by physical examination findings and is confirmed by echocardiography. We report two cases of severe tricuspid regurgitation secondary to the rupture of the chordae tendineae of the anterior leaflet following non-penetrating chest trauma. Both patients had uneventful postoperative courses.

Screening of carotid artery stenosis in coronary artery bypass grafting patients.

BACKGROUND: We sought to evaluate the routine echo-Doppler screening of carotid artery stenosis in patients undergoing coronary artery bypass grafting. METHODS: A total of 2179 consecutive patients who underwent coronary artery bypass grafting alone or with other cardiac surgery at Tehran Heart Center, Tehran-Iran, between January 2005 and January 2006 were included in this retrospective study. Carotid Doppler was performed for 1604 (81.48%) of these patients. RESULTS: The patients' age ranged between 20 and 84 years (mean: 58.33, SD: 10.08 years). Of the 1604 patients studied, 1186 (73.9%) were men, 592 (36.9%) had diabetes, 598 (37.3%) were smokers, and 194 (12.1%) cases had significant left main stenosis. Twenty-one (1.3%) patients had significant carotid stenosis (> 60% stenosis), which constituted 0.9% of all the bypass surgery candidates. Post-operative cerebrovascular accident was not detected in any of the patients with significant carotid stenosis, but cerebrovascular accident occurred in 22 (1.4%) of the patients without carotid stenosis. Magnetic resonance angiography (MRA) was conducted in 15 patients. In our univariate analysis, female gender (p value = 0.023), hypertension (p value = 0.055), peripheral vascular disease (p value < 0.001), and age (p value = 0.001) were significant in the development of carotid stenosis. CONCLUSION: Pre-operative duplex carotid screening seems to be necessary in patients when there is hypertension, peripheral vascular disease, female gender, and advanced age.