The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Mar 1991
Mitral valve repair by replacement of chordae tendineae with polytetrafluoroethylene sutures.
Expanded polytetrafluoroethylene sutures have been used for replacement of diseased chordae tendineae during reconstructive procedures on the mitral valve in 43 patients. There were 28 men and 15 women whose mean age was 55 years, range 21 to 76. Three fourths of the patients were in New York Heart Association class III or IV. ⋯ There have been two late deaths, neither one valve related. Replacement of chordae tendineae with polytetrafluoroethylene sutures is simple and allows for reconstruction of the mitral valve in many patients who would otherwise require mitral valve replacement. Because our patients have been followed up for a limited time, the long-term results of this procedure remain unknown.
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J. Thorac. Cardiovasc. Surg. · Mar 1991
Freehand allograft aortic valve replacement and aortic root replacement. Utility of intraoperative echocardiography and Doppler color flow mapping.
Seventeen consecutive patients undergoing 20 planned aortic valve replacements with allograft valves at Stanford University Medical Center were studied with intraoperative epicardial echocardiography and Doppler color flow mapping before and after cardiopulmonary bypass. Native aortic valves were replaced in 12 of the 20 patients, and eight patients underwent second aortic valve procedures. In 17 of 20 patients allograft selection was guided by prebypass echocardiographic estimates of annular diameter and/or length of allograft aortic root required. Other prebypass findings included unanticipated severe mitral regurgitation in one patient (which precluded allograft aortic valve replacement), left-to-right shunts in five patients, ascending aortic dissection in one, and aortic root disease necessitating coronary reimplantation or bypass in two. Postbypass echocardiography demonstrated acceptable competency of 18 of 19 allograft valves (mild or no aortic insufficiency). Postbypass echocardiography also documented successful repair of four of five shunts and mild mitral regurgitation in 15 of 19 patients (versus 11 of 19 before bypass). ⋯ Intraoperative echocardiography-Doppler mapping is a useful adjunct for allograft aortic valve or aortic root replacement; it allows confident selection of appropriate tissue size before aortic cross clamping, which minimizes delay from allograft thawing procedures. It also provides helpful information about the extent of aortic root disease and coronary ostial anatomy before bypass, confirms allograft competency after bypass, and detects accompanying valvular and other hemodynamic lesions before and after allograft valve replacement.
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J. Thorac. Cardiovasc. Surg. · Feb 1991
Lowering the calcium concentration in St. Thomas' Hospital cardioplegic solution improves protection during hypothermic ischemia.
The concentration of calcium (1.2 mmol/L) in clinical St. Thomas' Hospital cardioplegic solution was chosen several years ago after dose-response studies in the normothermic isolated heart. However, recent studies with creatine phosphate in St. ⋯ Thomas' Hospital solution precipitated the calcium paradox with massive enzyme release and no functional recovery. Unlike prior published calcium dose-response studies at normothermia, these results demonstrate that the optimal calcium concentration during clinically relevant hypothermic ischemia is considerably lower than that of normal serum ionized calcium (1.2 mmol/L) and appears ideal at 0.6 mmol/L to realize even greater cardioprotective and antiarrhythmic effects with St. Thomas' Hospital solution.
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J. Thorac. Cardiovasc. Surg. · Jan 1991
Prostaglandin F1 alpha levels during and after neonatal extracorporeal membrane oxygenation.
Infants receiving extracorporeal membrane oxygenation therapy undergo long-term cardiopulmonary bypass, are systemically heparinized, and frequently receive platelet transfusions. Prostacyclin is a powerful inhibitor of platelet aggregation as well as a potent vasodilator. The levels of its stable metabolite prostaglandin F1 alpha increase significantly in children undergoing cardiopulmonary bypass during heart operations but decrease to preoperative levels after bypass. ⋯ In most infants, prostaglandin F1 alpha levels rose again during weaning from extracorporeal membrane oxygenation and remained elevated for 24 hours after extracorporeal membrane oxygenation. Extracorporeal membrane oxygenation course influenced circulating prostaglandin F1 alpha levels. Fluctuating prostaglandin F1 alpha levels are of clinical significance in the management of vasomotor tone and platelet function, common problems in the care and the prevention of hemorrhage in these critically ill infants.
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J. Thorac. Cardiovasc. Surg. · Jan 1991
Neonatal repair of tetralogy of Fallot with and without pulmonary atresia.
Our experience with the arterial switch operation for transposition of the great arteries has confirmed the attainability of excellent results with elective neonatal surgery. Up to this time, we have repaired tetralogy of Fallot during the neonatal period only when symptoms, either severe persistent cyanosis or cyanotic spells, have been present. This review assesses the results of such nonelective neonatal correction of tetralogy between 1973 and 1988. ⋯ Postoperative catheterization of 15 long-term survivors showed right ventricular pressure less than 70% systemic in 13 cases. All patients are symptomatically well and functioning in sinus rhythm 1 to 15 years after repair (mean, 5 +/- 4 years). This experience with neonates with symptoms suggests that, if mortality is lower in the absence of symptoms, elective repair of tetralogy of Fallot could be reasonably undertaken during the first months of life.