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Objectives: Neuroprotection is of paramount interest in cardiac surgery. Right axillary artery cannulation is well established in aortic surgery because it significantly improves survival and outcome, but malperfusion of the right brain after direct cannulation has been reported. Anatomically, 4 vessel segments are potentially amenable for cannulation of the subclavian and axillary arteries. Clinical studies vary widely in dissection sites and cannulation techniques. We investigated critical flow dynamics in the right brain caused by arterial inflow after direct cannulation and specified cannulation positions that provide optimal cerebral perfusion., Methods: Distances from the lateral margin of the axillary artery and the subclavian artery to the origin of the vertebral artery were measured in 14 human corpses by a flexible ruler. We calculated the hemodynamics within the vertebral artery, depending on different positions of the cannula tip, in a computer-calculated model., Results: The mean distance from the axillary artery to the vertebral artery was 8.5 cm, and the mean distance from the subclavian artery to the vertebral artery was 6.7 cm. Computed flow calculations demonstrated reversed flow in the vertebral artery when the cannula tip was positioned too close to its orifice. To ensure safe supra-aortic flow, a cannula can be inserted securely up to 6.0 cm into the axillary artery and 4.2 cm into the subclavian artery., Conclusions: Direct cannulation of the right axillary artery can lead to cerebral malperfusion, caused by an obstruction of the vertebral artery's orifice by the arterial cannula or a subclavian steal phenomenon due to flow reversal. The safety of direct axillary artery cannulation can be improved by a well-considered dissecting site and insertion length of the cannula., (Copyright © 2013. Published by Mosby, Inc.)

Objectives: Optimal treatment strategies for patients with ischemic cardiomyopathy and moderately reduced left ventricular function remain controversial. We assessed the early and midterm outcomes after surgical revascularization alone versus revascularization and additional left ventricular remodeling in these patients., Methods: Between 2000 and 2003, 285 consecutive patients with coronary artery disease and moderately impaired left ventricular function (ejection fraction 30%-40%) were surgically treated with coronary artery bypass grafting alone (group 1, n = 165) or open left ventricular remodeling in addition to revascularization (group 2, n = 120). Preoperatively, the New York Heart Association class, left ventricular ejection fraction, and end-diastolic diameter were comparable. Early and midterm outcomes, hemodynamic performance, and quality of life assessed by Minnesota Quality of Life Questionnaire were evaluated during a mean follow-up period of 70 months., Results: Group 2 patients demonstrated significantly longer ventilation times, higher blood loss, and need for blood transfusion but had significantly lower operative mortality (4.5% compared with 8.5% in group 1). Seven-year follow-up demonstrated survival of 74.3% +/- 8.1% in group 1 versus 84.2% +/- 5.4% in group 2 (P < .05). Follow-up examinations revealed greater improvement of functional class in group 1 with mean 1.7 +/- 0.7 versus 2.03 +/- 0.8 in group 2 (P < .05). Cardiac-related hospital readmissions were comparable (3.8% vs 4.1%, P = .73)., Conclusions: Patients with ischemic cardiomyopathy, in whom surgical ventricular remodeling was possible and performed, experienced more perioperative complications but had superior early and midterm outcome regarding survival, functional class, and quality of life.

Objective: Venoarterial extracorporeal membrane oxygenation is an established treatment option in patients with cardiogenic shock. This report reviews our 3-year experience with this support system with respect to early and midterm outcome, as well as predictors of survival., Methods: From January 2003 until November 2006, 45 (0.8%) of 5750 patients undergoing cardiac surgery procedures required the following: temporary extracorporeal membrane oxygenation support coronary artery bypass grafting, n = 20; implantation of a left ventricular assist device, n = 5; heart transplantation, n = 1; heart and lung transplantation, n = 1; coronary artery bypass grafting plus repair of postinfarction ventricular septal defect, n = 3; coronary artery bypass grafting plus mitral valve repair, n = 5; aortic valve replacement, n = 2; coronary artery bypass grafting plus aortic valve replacement, n = 3; and other procedures, n = 5. Extracorporeal membrane oxygenation implantation was performed through the femoral vessels or axillary artery or through the right atrium and ascending aorta. Additional intra-aortic balloon pumps were used in 30 patients., Results: Average patient age was 60.1 +/- 13.6 years. There were 35 male patients. Average duration of extracorporeal membrane oxygenation was 6.4 +/- 4.5 days. Twenty-five patients could be successfully weaned from extracorporeal membrane oxygenation. The 30-day mortality was 53% (24/45 patients). The in-hospital mortality was 71% (32/45 patients). Thirteen (29%) patients could be successfully discharged. After a follow-up period of up to 3 years, 10 (22%) patients were still alive., Conclusions: Extracorporeal membrane oxygenation offers sufficient cardiopulmonary support in adults with similar hospital and midterm survival rates to those of other mechanical support systems. Early indication, alternative peripheral cannulation techniques, and reduced anticoagulation to avoid perioperative bleeding could improve our results with increasing experience.

Objectives: In vitro testing of biologic valves has been performed using only fresh but treated valves suitable for patient implantation. The present study investigates changes in hemodynamic performance and leaflet kinematics in progressively calcified porcine and pericardial aortic valve prostheses., Methods: Edwards Perimount Magna (Edwards Lifesciences, Irvine, Calif) (n = 5) and Medtronic Mosaic Ultra (Medtronic Inc, Minneapolis, Minn) (n = 5) heart valves (23 mm) were investigated in an artificial circulation system (70 beats/min, cardiac output 5 L/min). Leaflet kinematics were visualized with a high-speed camera (3000 frames/sec). Valves were then exposed to a calcium-phosphate solution at a constant pulse rate of 300 beats/min for a total of 6 weeks. Repeated testing was performed after 1, 2, 3, 4, and 6 weeks of calcification. The calcification process might not be similar to in vivo performance., Results: Initially, the Perimount Magna valves demonstrated lower pressure gradients compared with the Mosaic Ultra valves (9.7 +/- 0.36 mm Hg vs 14.0 +/- 1.16 mm Hg), but they showed higher closing volume and leakage flow. Total energy loss was equivalent after 1 week of calcification. Perimount Magna valves calcified significantly faster and more severely, leading to an increase in gradients and closure volume. Leaflet kinematics showed progressively longer opening and closing times for the pericardial valves (closing time Perimount Magna 135 +/- 11 msec vs Mosaic Ultra 85 +/- 9 msec after 6 weeks)., Conclusions: On the basis of visual inspection, despite the new ThermaFix (Edwards Lifesciences) tissue treatment, the Perimount Magna pericardial valves calcified in vitro faster and more severely than did the Mosaic Ultra porcine valves, which demonstrated a more constant performance throughout the calcification process. Leaflet kinematics showed a progressive prolongation of opening and closing times for pericardial valves, leading to higher closing volume.

Objective: Atrial fibrillation is one of the most common complications in patients undergoing coronary artery bypass grafting. The goal of this study was to investigate the impact of high thoracic epidural anesthesia on reduction of perioperative arrhythmia in patients undergoing off-pump coronary artery bypass grafting., Methods: We prospectively randomized 132 patients undergoing elective off-pump coronary bypass grafting using either general anesthesia (GA) (n = 66) or combined general and high thoracic epidural anesthesia (GA+TEA) (n = 66). Incidence of perioperative arrhythmias such as atrial fibrillation, serum epinephrine levels, heart rate variability, and hemodynamic parameters were compared between groups., Results: The incidence of perioperative dysarrhythmias was significantly lower (P < .01) in the GA+TEA group (3%) than in the GA group (23.7%). Intraoperative sinus bradycardia occurred in 91% of the patients in the GA+TEA group versus 5.3% in the GA group. After induction of anesthesia, the mean systolic arterial pressure decreased significantly from 128 +/- 5 to 92 +/- 4 mm Hg and the heart rate from 74 +/- 9 to 52 +/- 8 beats . min(-1) in the GA+TEA group, whereas in the GA group no significant hemodynamic changes were observed (P < .001). Serum epinephrine levels were significantly lower in the GA+TEA group (69 +/- 11 to 35 +/- 7 ng/dL) than in the GA group (72 +/- 9 to 70 +/- 9 ng/dL)., Conclusions: In our study cohort, high thoracic epidural anesthesia in combination with general anesthesia reduced significantly the incidence of perioperative arrhythmias such as atrial fibrillation. Furthermore, we observed a significant reduction of epinephrine serum levels in this patient group. The results of this study support a combination of general anesthesia with thoracic epidural anesthesia as a multidisciplinary approach, which may lead to a better patient outcome, improvement of early analgesia, and reduction of perioperative complications in off-pump coronary artery bypass procedures. The potential risks of thoracic epidural anesthesia during off-pump coronary artery bypass procedures should not be underestimated.

Objective: In some randomized studies, stentless aortic valves have demonstrated hemodynamic advantages in comparison with stented prostheses. The effect of more physiologic flow dynamics on coronary artery flow has not been investigated yet. This study compares coronary perfusion after aortic valve replacement with stented or stentless porcine bioprostheses in a prospective randomized study., Methods: A total of 24 patients (73 +/- 6 years) referred for treatment of aortic stenosis were randomized to aortic valve replacement with stented (Medtronic Mosaic; (Medtronic Inc, Minneapolis, Minn) or stentless (Medtronic Freestyle; Medtronic Inc) prostheses. Coronary flow was measured by means of magnetic resonance imaging preoperatively, 5 days after the operation, and 6 months postoperatively, then with evaluation of coronary flow reserve. Echocardiography was performed to quantify transvalvular gradients and left ventricular mass regression., Results: Coronary flow increased in both groups significantly (P < .001) after aortic valve replacement. This increase was higher in the stentless group compared with that seen in the stented group (343 +/- 137 vs 221 +/- 66 mL/min). Also, coronary flow reserve was higher for stentless valves (3.4 +/- 0.3 for stentless valves and 2.3 +/- 0.1 for stented valves). Mean pressure gradients for Freestyle valves were lower (10 +/- 4 and 8 +/- 3 mm Hg, respectively, vs 19 +/- 6 postoperatively and 15 +/- 4 mm Hg at follow-up for Mosaic valves, P < .05). Left ventricular mass regression was similar in both groups., Conclusions: Normalization of coronary artery flow after aortic valve replacement for aortic stenosis was more pronounced for stentless valves compared with stented valves. The fact that the stentless design also demonstrated a superior hemodynamic performance with lower pressure gradients might be explained by the design being closer to physiologic anatomy and thus the presence of lower turbulence levels in the sinuses of Valsalva.