Redo sternotomy for cardiac reoperations using peripheral heparin-bonded cardiopulmonary bypass circuits without systemic heparinization: technique and results.

OBJECTIVE: Cardiac reoperations are challenging and time-consuming and incur a high incidence of perioperative complications because of injuries to cardiac structures, bleeding, and hemodynamic instability. Some centers are using extracorporeal circulation with heparinization at the time of resternotomy, but it leads to prolonged anticoagulation, platelet dysfunction, fibrinolysis, coagulopathy, and morbidity. The authors routinely perform resternotomy in complex surgery with the support of heparinless cardiopulmonary bypass with heparin-bonded circuits (HBCs). The authors describe their technique, indication, and results. METHODS: The femoral artery or axillary artery and femoral veins are cannulated before sternotomy, and cardiopulmonary bypass is instituted using an HBC without systemic heparinization. Systemic heparin (200-300 U/kg) is administered when all structures are isolated before aortic cross-clamping (activated coagulation time >400 seconds). RESULTS: Between 1996 and 2008, 336 patients underwent redo sternotomy using the HBC for complex cardiac procedures, with 29 deaths (8.6% deaths within 30 days). Only 5 (1.5%) of 336 patients sustained injury to the right ventricle, aorta, bypass grafts, or ventricular fibrillation during re-entry without hemodynamic deterioration; and underwent uneventful repair and outcomes. There was no online HBC thrombosis. CONCLUSIONS: This study shows that HBC without systemic heparinization during resternotomy can be used safely in complex redo cardiac surgery. The heart is completely decompressed during the resternotomy, allowing easy dissection, less likely injury to vital structures, and less bleeding without compromising the hemodynamics.

Long-term survival after use of internal thoracic artery in octogenarians is gender related.

OBJECTIVE: The goal of this study is to assess the benefits of a left internal thoracic artery as a bypass conduit in octogenarians undergoing elective coronary artery bypass grafting. We hypothesize that there is no survival advantage and that outcome may be gender related. METHODS: In a retrospective analysis of 1141 octogenarians (aged >80 years) undergoing isolated coronary artery bypass grafting from 1996 to 2012, patients were divided into 2 groups: Group I (coronary artery bypass grafting-left internal thoracic artery) included 870 patients (339 female/531 male), and group II (coronary artery bypass grafting-saphenous vein graft) included 271 patients (131 female/140 male). RESULTS: The overall 30-day mortality was 5.7%: 4.3% in group I and 7.0% in group II (P = .1). Group II had a lower trend of any postoperative complication (P = .05) and pneumonia (P = .05). When analyzed by gender, there were no discernable differences in long-term survival for male patients in group I (65% at 5 years and 29% at 10 years) versus male patients in group II (65% at 5 years and 31% at 10 years) (P = .2). However, survival was significantly greater for female patients in group I (70% at 5 years and 35% at 10 years) versus female patients in group II (63% at 5 years and 21% at 19 years) (P = .01). Multiple logistic and Cox regression analysis showed that left internal thoracic artery use is associated with improved survival in female patients (hazard ratio [HR], 0.72; confidence interval [CI], 0.56-0.93) but not in male patients (HR, 1.14; CI, 0.9-1.4). Advanced age was associated with an increased risk of mortality (HR, 1.08 per year; CI, 1.05-1.1). Both patient age (P = .01) and Society of Thoracic Surgeons-predicted 30-day mortality (P = .03) remain in the final model for 30-day mortality. The benefit of the left internal thoracic artery after coronary artery bypass grafting in octogenarians may be gender related. CONCLUSIONS: This study shows that the benefit of the left internal thoracic artery in the octogenarian population undergoing coronary artery bypass grafting may be gender related. For elderly female patients, the use of the left internal thoracic artery as a bypass conduit was associated with better long-term survival, whereas no significant difference was found among the male population. The use of the left internal thoracic artery was associated with a greater postoperative pulmonary morbidity for the study population as a whole. The present study does not refute the benefit of the left internal thoracic artery-left anterior descending graft, but instead distinguishes a subset who might benefit more.

Mycotic ascending aortic pseudoaneurysm secondary to pseudomonas mediastinitis at the aortic cannulation site.

During the last 5 years, postoperative Pseudomonas mediastinitis has occurred in 2 of the 3,072 patients in our institution who have undergone cardiopulmonary bypass cardiac operations via a sternotomy. To our knowledge, there is no prior report in the English-language literature of postoperative Pseudomonas mediastinitis that originated at the aortic cannulation site, yet that was the site of origin in both of these patients. The 1st patient developed a mycotic pseudoaneurysm of the ascending aorta at the cannulation site, secondary to the development of Pseudomonas mediastinitis following aortic valve replacement. This sequela was successfully treated by means of aneurysmectomy and closure of the aorta with a bovine pericardial patch, under cardiopulmonary bypass with circulatory arrest. The 2nd patient developed pseudoaneurysm and perforation of the aorta at the cardioplegia needle site, secondary to Pseudomonas mediastinitis following aortic and mitral valve replacement. This patient died. In both patients, the cannulation site and the cardioplegia needle site had been closed with pledgeted sutures. Pseudomonas aeruginosa was cultured from both sites. Once the diagnosis of Pseudomonas mediastinitis is made following heart surgery, the patient should undergo reoperation, if possible, for removal of the foreign bodies (pledgeted sutures). In addition, these patients should be monitored with chest magnetic resonance angiography every 3 months for 1 year, in order to diagnose early development of a mycotic pseudoaneurysm and subsequent complications.

Impaired contractile response of human peripheral arterioles to thromboxane A-2 after cardiopulmonary bypass.

BACKGROUND: We studied the contractile response of human peripheral microvasculature to thromboxane A-2 (TXA-2) before and after cardiopulmonary bypass (CPB), with and without the blockade of TXA-2 receptors, or the inhibition of phospholipase C (PLC), phospholipase A-2 (PLA-2) or protein kinase C (PKC)-α. We also examined the protein/gene expression and localization of TXA-2 receptors, TXA-2 synthase, PLC, and other TXA-2-related proteins. METHODS: Skeletal muscle arterioles (90-180 µm in diameter) were harvested pre- and post-CPB from patients (n = 28) undergoing cardiac surgery. RESULTS: The post-CPB contractile response of skeletal muscle arterioles to TXA-2 analog U-46619 was impaired compared with pre-CPB (P < .05). The presence of TXA-2 receptor antagonist SQ-29548 (10(-6)mol/L) prevented the contractile response to U-46619 (P < .05). Pretreatment with the PLC inhibitor U-73122 (10(-6)mol/L) significantly inhibited the U-46619-induced contractile response (P < .01). Administration of the PLA-2 inhibitor quinacrine (10(-6)mol/L) or PKC-α inhibitor safingol (2 × 10(-5)mol/L), however, failed to affect U-46619-induced contraction. Total protein levels and gene expression of TXA-2 receptors, and TXA-2 synthase of skeletal muscle, were not altered post-CPB. Confocal microscopy showed no differences in the expression of PLCß-3 in the microcirculation. PLCß-3 was localized to both smooth muscle and endothelium. CONCLUSION: CPB decreases the contractile response of human peripheral arterioles to TXA-2 soon after cardiac surgery. This response may be in part responsible for the decrease in vascular tone, and accompanying hypotension sometimes observed after cardiac operations utilizing CPB.