The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jan 2005
Comparative StudyImpaired mitochondrial response to simulated ischemic injury as a predictor of the development of atrial fibrillation after cardiac surgery: in vitro study in human myocardium.
Atrial fibrillation occurs in 20% to 40% of patients after cardiac surgery, but its pathophysiology remains unclear. Recent studies demonstrated preexisting histologic markers that portend the development of postoperative atrial fibrillation. In this prospective study, we focused on mitochondrial dysfunction in response to ischemic stress as a potential predictor for postoperative atrial fibrillation. ⋯ This study has identified for the first time an association between mitochondrial dysfunction in response to ischemia and postoperative atrial fibrillation. This finding improves our understanding of the pathophysiology of postoperative atrial fibrillation and may eventually lead us to identify candidates for selective preoperative or early postoperative prophylactic treatment.
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J. Thorac. Cardiovasc. Surg. · Jan 2005
Comparative StudyEffect of sensory substitution on suture-manipulation forces for robotic surgical systems.
Direct haptic (force or tactile) feedback is not yet available in commercial robotic surgical systems. Previous work by our group and others suggests that haptic feedback might significantly enhance the execution of surgical tasks requiring fine suture manipulation, specifically those encountered in cardiothoracic surgery. We studied the effects of substituting direct haptic feedback with visual and auditory cues to provide the operating surgeon with a representation of the forces he or she is applying with robotic telemanipulators. ⋯ Sensory substitution, in the form of visual feedback, auditory feedback, or both, confers quantifiable advantages in applied force accuracy and consistency during the performance of a simple surgical task.
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J. Thorac. Cardiovasc. Surg. · Jan 2005
Comparative StudyConventional and sutureless techniques for management of the pulmonary veins: Evolution of indications from postrepair pulmonary vein stenosis to primary pulmonary vein anomalies.
We have previously reported a limited but favorable experience with a novel sutureless technique for surgical management of postoperative pulmonary vein stenosis occurring after repair of total anomalous pulmonary venous drainage. Because this technique requires integrity of the retrocardiac space for hemostasis, extension of the technique to the primary repair of pulmonary vein anomalies requires evaluation. This analysis reviews our experience with the sutureless technique in patients with postrepair pulmonary vein stenosis, as well as our extension of the technique into primary repair of pulmonary vein anomalies. ⋯ The sutureless technique for postrepair pulmonary vein stenosis is associated with encouraging midterm results. Extension of the indications for the technique to primary repair appears safe with the development of simple intraoperative maneuvers.
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J. Thorac. Cardiovasc. Surg. · Jan 2005
Comparative StudyMaintenance of pulmonary vasculature tone by blood derived from the inferior vena cava in a rabbit model of cavopulmonary shunt.
After cavopulmonary shunt in which the superior vena cava is anastomosed to the right pulmonary artery, the right lung is in a unique condition without flow pulsatility and hepatic venous effluent. In a previous study, we reported that hypoxic pulmonary vasoconstriction disappeared in the pulmonary circulation after cavopulmonary shunt. In this study, however, to investigate the influence of pulsatility and hepatic venous effluent on hypoxic pulmonary vasoconstriction in the pulmonary circulation, we developed an alternative cavopulmonary shunt rabbit model that included hepatic venous effluent in the pulmonary circulation and reduced the pulsatility of the pulmonary arterial blood flow. We then observed the physiologic characteristics of the peripheral pulmonary artery after cavopulmonary shunt, specifically the disappearance of hypoxic pulmonary vasoconstriction. ⋯ We developed a cavopulmonary shunt rabbit model in which the inferior vena caval blood was derived from the right ventricle. Hypoxic pulmonary vasoconstriction was maintained in the model with the blood flow from the right ventricle. When the blood flow was not maintained, however, hypoxic pulmonary vasoconstriction disappeared. This phenomenon strongly suggests that a substance in hepatic venous effluent partially regulates the physiological pulmonary vascular function in the rabbit lung.
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J. Thorac. Cardiovasc. Surg. · Jan 2005
Comparative StudyIloprost to improve surfactant function in porcine pulmonary grafts stored for twenty-four hours in low-potassium dextran solution.
The optimal strategy for pulmonary graft preservation remains elusive. Experimental work and initial clinical experience support low-potassium dextran solutions as lung perfusates. We have previously shown a protective effect of prostaglandin E 1 on ischemia-reperfusion injury in lung transplantation by a shift from proinflammatory to anti-inflammatory cytokines in a rat lung transplantation model. In this study, we tested the hypothesis that the addition of a prostacyclin analog (iloprost) to low-potassium dextran might lead to improved surfactant and ultimately graft function. ⋯ Modification of low-potassium dextran solution with the prostacyclin analog iloprost resulted in a significant amelioration of ischemia-reperfusion injury and improved preservation of surfactant function in transplanted lungs. This intriguing approach merits further evaluation with respect to the mechanisms involved and, ultimately, potential introduction into clinical lung transplantation.