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Michael Tynan - One of the best experts on this subject based on the ideXlab platform.
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Percutaneous Pulmonary valvotomy and arterial duct stenting in neonates with right ventricular hypoplasia
The American journal of cardiology, 1994Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, Michael TynanAbstract:Abstract In neonates with critical Pulmonary Valve stenosis or Atresia associated with intact ventricular septum, the prognosis is determined by the size of the right ventricle. If the right ventricle is of a satisfactory size, Pulmonary valvotomy alone is the treatment of choice. 1 If the right ventricle is hypoplastic, a systemic to Pulmonary artery shunt is performed in addition to the Pulmonary valvotomy to maintain Pulmonary blood flow. If the right ventricle is extremely small, only a shunt is usually performed. Subsequently, a biventricular circulation is achieved in those in whom the right ventricular size and function are adequate, but the remaining neonates are candidates for a Fontan repair. In patients with critical Pulmonary Valve stenosis, balloon dilation of the Pulmonary Valve is now the treatment of choice. 2 More recently, in patients with Pulmonary Valve Atresia, percutaneous laserand radiofrequency-assisted balloon valvotomy have been shown to be feasible. 3,4 Patients in whom the right ventricle is unable to support the Pulmonary circulation are either given a prolonged infusion of prostaglandins to maintain arterial duct patency or have a systemic to Pulmonary artery shunt created in the neonatal period. Neither of these options is without morbidity or complications. After experimental assessment 5 we have used an alternative nonsurgical approach to maintain patency of the arterial duct by implantation of a stent.
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Technique of percutaneous laser-assisted Valve dilatation for valvar Atresia in congenital heart disease.
British heart journal, 1993Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, Ashok Kakadekar, Rui Anjos, E J Baker, Michael TynanAbstract:OBJECTIVE--To investigate the efficacy and safety of transcatheter laser-assisted Valve dilatation for atretic Valves in children with congenital heart disease. DESIGN--Prospective clinical study. SETTING--Supraregional paediatric cardiology centre. SUBJECTS--Eleven children (aged 1 day-11 years; weight 2.1-35.7 kg) with Atresia of Pulmonary (10) or tricuspid (one) Valve underwent attempted laser-assisted Valve dilatation as part of the staged treatment of their cyanotic heart disease. INTERVENTION--After delineating the atretic Valve by angiography and/or echocardiography a 0.018 inch "hot tip" laser wire was used to perforate the atretic Valve. Subsequently the Valve was dilated with conventional balloon dilatation catheters up to the Valve annulus diameter. RESULTS--Laser-assisted Valve dilatation was successfully accomplished in nine children. In two neonates with Pulmonary Valve Atresia, intact ventricular septum, and coexistent infundibular Atresia the procedure resulted in cardiac tamponade: one died immediately and one later at surgery. During a follow up of 1-17 months (mean 11) two infants with Pulmonary Valve Atresia and intact ventricular septum died (one with congestive cardiac failure). The remainder are either well palliated and do not require further procedures (three), or are awaiting further transcatheter or surgical procedures because of associated defects (four). CONCLUSIONS--Laser-assisted Valve dilatation is a promising adjunct to surgery in this high risk group of patients. It may avoid surgery in some patients, and may reduce the number of surgical procedures in those requiring staged operations.
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Radiofrequency-assisted balloon dilatation in patients with Pulmonary Valve Atresia and an intact ventricular septum.
British heart journal, 1993Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, K C Chan, Robin P. Martin, D J Skehan, S C Jordan, Michael TynanAbstract:OBJECTIVE--To investigate the efficacy and safety of transcatheter radiofrequency-assisted Valve dilatation for infants with Pulmonary Valve Atresia and intact ventricular septum as an alternative to the use of laser heated wires. DESIGN--Prospective clinical study. SETTING--Three paediatric cardiology centres. PATIENTS--Four children (aged 5-101 days, weight 2.8 kg) with Pulmonary Valve Atresia and intact ventricular septum underwent percutaneous radiofrequency-assisted Valve dilatation. METHODS--After delineating the atretic Valve by angiography, 0.020 inch or 0.018 inch radiofrequency wires were used to perforate the atretic Valve. The Valve was then dilated with conventional balloon dilatation catheters up to the Valve annulus diameter. RESULTS--In all four cases the radiofrequency wire perforated the atretic Pulmonary Valve and balloon dilatation was successful. In one patient the radiofrequency wire also passed through the anterior wall of the Pulmonary artery causing tamponade which required surgical repair shortly afterwards. This patient died from sepsis six days later. One patient died three weeks after the procedure from septicaemia and a paradoxical coronary embolus. Two patients were discharged after 4 and 14 days respectively. CONCLUSIONS--Radiofrequency-assisted Valve dilatation is a promising alternative to the recently developed laser wire technique. The major advantages are a reduction in cost and improved safety for the staff performing the procedure.
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Laser-assisted tricuspid Valve balloon dilation for acquired tricuspid Valve Atresia
European heart journal, 1992Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, A. P. Kakadekkar, Michael TynanAbstract:Acquired Pulmonary Valve Atresia is a well-recognized but uncommon complication of surgical systemic-to-Pulmonary artery shunts in patients with tetralogy of Fallot. Acquired Atresia of the tricuspid Valve, however, has not been reported previously. This complication developed in a 3-year-old girl, with Pulmonary Atresia and an intact ventricular septum, after a Blalock-Taussig shunt and right ventricular outflow tract reconstruction. Percutaneous transcatheter laser-assisted balloon dilation re-established antegrade flow across the tricuspid Valve.
Eric Rosenthal - One of the best experts on this subject based on the ideXlab platform.
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Unguarded tricuspid orifice with Pulmonary Atresia: successful radiofrequency ablation of an accessory pathway in an infant
Heart (British Cardiac Society), 1998Co-Authors: Alan G. Magee, Eric Rosenthal, Julian Bostock, Jaswinder GillAbstract:A male infant with the rare lesion of unguarded tricuspid orifice in the setting of Pulmonary Valve Atresia, intact ventricular septum, and a hypoplastic right ventricle is described. The patient presented with cyanosis at 1 day old; transcutaneous oxygen saturations were between 20% and 30% in room air, and 60% in 100% inspired oxygen. Pre-excitation was found incidentally on the ECG and the potential for rapid antegrade conduction of atrial tachyarrhythmias, after eventual extended palliation with the Fontan procedure, was demonstrated at electrophysiological study. By 11 months old the patient was becoming increasingly cyanosed and interim palliation with a bidirectional cavoPulmonary shunt was proposed. Successful radiofrequency ablation of the accessory pathway was performed before bidirectional cavoPulmonary shunt, which would have prevented access to the heart via the superior vena cava. Difficulty with femoral venous access because of previous occlusion of a femoral vein was overcome by the use of 2 F pacing electrodes and a 5 F ablation catheter. Keywords: radiofrequency ablation; accessory pathway; unguarded tricuspid orifice
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Percutaneous Pulmonary valvotomy and arterial duct stenting in neonates with right ventricular hypoplasia
The American journal of cardiology, 1994Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, Michael TynanAbstract:Abstract In neonates with critical Pulmonary Valve stenosis or Atresia associated with intact ventricular septum, the prognosis is determined by the size of the right ventricle. If the right ventricle is of a satisfactory size, Pulmonary valvotomy alone is the treatment of choice. 1 If the right ventricle is hypoplastic, a systemic to Pulmonary artery shunt is performed in addition to the Pulmonary valvotomy to maintain Pulmonary blood flow. If the right ventricle is extremely small, only a shunt is usually performed. Subsequently, a biventricular circulation is achieved in those in whom the right ventricular size and function are adequate, but the remaining neonates are candidates for a Fontan repair. In patients with critical Pulmonary Valve stenosis, balloon dilation of the Pulmonary Valve is now the treatment of choice. 2 More recently, in patients with Pulmonary Valve Atresia, percutaneous laserand radiofrequency-assisted balloon valvotomy have been shown to be feasible. 3,4 Patients in whom the right ventricle is unable to support the Pulmonary circulation are either given a prolonged infusion of prostaglandins to maintain arterial duct patency or have a systemic to Pulmonary artery shunt created in the neonatal period. Neither of these options is without morbidity or complications. After experimental assessment 5 we have used an alternative nonsurgical approach to maintain patency of the arterial duct by implantation of a stent.
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Technique of percutaneous laser-assisted Valve dilatation for valvar Atresia in congenital heart disease.
British heart journal, 1993Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, Ashok Kakadekar, Rui Anjos, E J Baker, Michael TynanAbstract:OBJECTIVE--To investigate the efficacy and safety of transcatheter laser-assisted Valve dilatation for atretic Valves in children with congenital heart disease. DESIGN--Prospective clinical study. SETTING--Supraregional paediatric cardiology centre. SUBJECTS--Eleven children (aged 1 day-11 years; weight 2.1-35.7 kg) with Atresia of Pulmonary (10) or tricuspid (one) Valve underwent attempted laser-assisted Valve dilatation as part of the staged treatment of their cyanotic heart disease. INTERVENTION--After delineating the atretic Valve by angiography and/or echocardiography a 0.018 inch "hot tip" laser wire was used to perforate the atretic Valve. Subsequently the Valve was dilated with conventional balloon dilatation catheters up to the Valve annulus diameter. RESULTS--Laser-assisted Valve dilatation was successfully accomplished in nine children. In two neonates with Pulmonary Valve Atresia, intact ventricular septum, and coexistent infundibular Atresia the procedure resulted in cardiac tamponade: one died immediately and one later at surgery. During a follow up of 1-17 months (mean 11) two infants with Pulmonary Valve Atresia and intact ventricular septum died (one with congestive cardiac failure). The remainder are either well palliated and do not require further procedures (three), or are awaiting further transcatheter or surgical procedures because of associated defects (four). CONCLUSIONS--Laser-assisted Valve dilatation is a promising adjunct to surgery in this high risk group of patients. It may avoid surgery in some patients, and may reduce the number of surgical procedures in those requiring staged operations.
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Radiofrequency-assisted balloon dilatation in patients with Pulmonary Valve Atresia and an intact ventricular septum.
British heart journal, 1993Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, K C Chan, Robin P. Martin, D J Skehan, S C Jordan, Michael TynanAbstract:OBJECTIVE--To investigate the efficacy and safety of transcatheter radiofrequency-assisted Valve dilatation for infants with Pulmonary Valve Atresia and intact ventricular septum as an alternative to the use of laser heated wires. DESIGN--Prospective clinical study. SETTING--Three paediatric cardiology centres. PATIENTS--Four children (aged 5-101 days, weight 2.8 kg) with Pulmonary Valve Atresia and intact ventricular septum underwent percutaneous radiofrequency-assisted Valve dilatation. METHODS--After delineating the atretic Valve by angiography, 0.020 inch or 0.018 inch radiofrequency wires were used to perforate the atretic Valve. The Valve was then dilated with conventional balloon dilatation catheters up to the Valve annulus diameter. RESULTS--In all four cases the radiofrequency wire perforated the atretic Pulmonary Valve and balloon dilatation was successful. In one patient the radiofrequency wire also passed through the anterior wall of the Pulmonary artery causing tamponade which required surgical repair shortly afterwards. This patient died from sepsis six days later. One patient died three weeks after the procedure from septicaemia and a paradoxical coronary embolus. Two patients were discharged after 4 and 14 days respectively. CONCLUSIONS--Radiofrequency-assisted Valve dilatation is a promising alternative to the recently developed laser wire technique. The major advantages are a reduction in cost and improved safety for the staff performing the procedure.
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Laser-assisted tricuspid Valve balloon dilation for acquired tricuspid Valve Atresia
European heart journal, 1992Co-Authors: Eric Rosenthal, Shakeel A. Qureshi, A. P. Kakadekkar, Michael TynanAbstract:Acquired Pulmonary Valve Atresia is a well-recognized but uncommon complication of surgical systemic-to-Pulmonary artery shunts in patients with tetralogy of Fallot. Acquired Atresia of the tricuspid Valve, however, has not been reported previously. This complication developed in a 3-year-old girl, with Pulmonary Atresia and an intact ventricular septum, after a Blalock-Taussig shunt and right ventricular outflow tract reconstruction. Percutaneous transcatheter laser-assisted balloon dilation re-established antegrade flow across the tricuspid Valve.
Eduardo Zambrano - One of the best experts on this subject based on the ideXlab platform.
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Pulmonary Atresia with intact ventricular septum (PA-IVS) in monozygotic twins.
American Journal of Medical Genetics Part A, 2008Co-Authors: Danielle De Stefano, Bixia Xiang, Pei Hui, Eduardo ZambranoAbstract:Pulmonary Atresia with intact ventricular septum (PA-IVS) is a rare congenital heart defect (CHD) of unknown etiology, characterized by an atretic Pulmonary Valve with the right ventricle varying in size and morphology among different affected individuals. We report on monozygotic (monochorionic diamnionic) twin sisters with PA-IVS who died soon after birth. The patients were prematurely born at 27 weeks by caesarean to a 24-year-old gravida 1, para 0 Hispanic mother. The pregnancy course was previously uneventful, and the mother denied any exposures during pregnancy. Both parents were healthy, nonconsanguineous, with no known family history of CHD in a three-generation pedigree. The Apgar scores were 5 and 7 (Twin A), and 4 and 6 (Twin B), at 1 and 5 min, respectively. Birth weight was 1,050 g (60th centile, Twin A) and 910 grams (40th centile, Twin B), crown-heel length was 35 cm for both twins, and occipital-frontal circumferences were 24.8 cm (Twin A) and 25 cm (Twin B). Soon after birth, Twin A developed increasing respiratory rate requiring mechanical ventilation, and a systolic ejection murmur at the left upper sternal border was noted accompanied by poor oxygen saturations. Chest X-ray revealed hazy, granular lung fields consistent with hyaline membrane disease as well as a cardiac silhouette occupying nearly 70% of the thoracic diameter. An echocardiogram revealed an annular-type Pulmonary Valve Atresia, and aortic stenosis with a bicuspid aortic Valve. The left ventricle appeared normal in size and function. In spite of therapy, the patient developed respiratory failure and died at the age of 3 days. TwinB had a similar clinical course and the echocardiogram also showed Pulmonary Valve Atresia (without aortic Atresia), suprasystemic right ventricular systolic pressures and moderate tricuspid regurgitation. On day 3 of life, the echocardiogram showed poor cardiac function with left ventricular ejection fraction of 45%. Grade IV germinal matrix hemorrhage was detected by ultrasound. Comfort care was provided, and she died on day 7 of life. Unrestricted postmortem examinations, following perinatal autopsy protocols were performed in both patients. The cardiac findings present in both twins were virtually identical, consistent with the diagnosis of PA-IVS, and characterized by cardiomegaly Twin A: 16.5 g; Twin B: 15.2 g), marked right atrial dilatation, marked right ventricular myocardial hypertrophy (8–10 mm in thickness) and a small right ventricular chamber measuring approximately 9 mm from the atrioventricular annulus to the apical aspect of the chamber. In both cases, the tricuspid Valves were dysplastic with two identifiable thick leaflets, attached to the right ventricular endocardium through markedly short and thickened chorda tendineae and papillary muscles. The Pulmonary Valvewas completely atretic in bothpatients, with three fused Valves leaving no identifiable lumen. In addition, in twin A the aortic Valve was bicuspid with thick, dysplastic leaflets. All other cardiac structures appeared within normal limits in both twins, and no other dysmorphic features besides the congenital heart defects were present in either twin. In particular, no short sternum, abnormal palmar creases or camptodactyly were noted.
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Research Letter Pulmonary Atresia With Intact Ventricular Septum (PA-IVS) in Monozygotic Twins
2008Co-Authors: Danielle De Stefano, Bixia Xiang, Pei Hui, Eduardo ZambranoAbstract:To the Editor: Pulmonary Atresia with intact ventricular septum (PA-IVS) is a rare congenital heart defect (CHD) of unknown etiology, characterized by an atretic Pulmonary Valve with the right ventricle varying in size and morphology among different affected individuals. We report on monozygotic (monochorionic diamnionic) twin sisters with PA-IVS who died soon after birth. The patients were prematurely born at 27 weeks by caesarean to a 24-year-old gravida 1, para 0 Hispanic mother. The pregnancy course was previously uneventful, and the mother denied any exposures during pregnancy. Both parents were healthy, nonconsanguineous, with no known family history of CHD in a three-generation pedigree. The Apgar scores were 5 and 7 (Twin A), and 4 and 6 (Twin B), at 1 and 5 min, respectively. Birth weight was 1,050 g (60th centile, Twin A) and 910 grams (40th centile, Twin B), crown-heel length was 35 cm for both twins, and occipital-frontal circumferences were 24.8 cm (Twin A) and 25 cm (Twin B). Soon after birth, Twin A developed increasing respiratory rate requiring mechanical ventilation, and a systolic ejection murmur at the left upper sternal border was noted accompanied by poor oxygen saturations. Chest X-ray revealed hazy, granular lung fields consistent with hyaline membrane disease as well as a cardiac silhouette occupying nearly 70% of the thoracic diameter. An echocardiogram revealed an annular-type Pulmonary Valve Atresia, and aortic stenosis with a bicuspid aortic Valve. The left ventricle appeared normal in size and function. In spite of therapy, the patient developed respiratory failure and died at the age of 3 days. Twin B had a similar clinical course and the echocardiogram also showed Pulmonary Valve Atresia (without aortic Atresia), suprasystemic right ventricular systolic pressures and moderate tricuspid regurgitation. On day 3 of life, the echocardiogram showed poor cardiac function with left ventricular ejection fraction of 45%. Grade IV germinal matrix hemorrhage was detected by ultrasound. Comfort care was provided, and she died on day 7 of life. Unrestricted postmortem examinations, following perinatal autopsy protocols were performed in both patients. The cardiac findings present in both twins were virtually identical, consistent with the diagnosis of PA-IVS, and characterized by cardiomegaly Twin A: 16.5 g; Twin B: 15.2 g), marked right atrial dilatation, marked right ventricular myocardial hypertrophy (8–10 mm in thickness) and a small right ventricular chamber measuring approximately 9 mm from the atrioventricular annulus to the apical aspect of the chamber. In both cases, the tricuspid Valves were dysplastic with two identifiable thick leaflets, attached to the right ventricular endocardium through markedly short and thickened chorda tendineae and papillary muscles. The Pulmonary Valve was completely atretic in both patients, with three fused Valves leaving no identifiable lumen. In addition, in twin A the aortic Valve was bicuspid with thick, dysplastic leaflets. All other cardiac structures appeared within normal limits in both twins, and no other dysmorphic features besides the congenital heart defects were present in either twin. In particular, no short sternum, abnormal palmar creases or camptodactyly were noted.
Gerd Hausdorf - One of the best experts on this subject based on the ideXlab platform.
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Maldevelopment of conotruncal and aorto-Pulmonary septum with absent left central Pulmonary artery: anatomical and clinical implications.
British heart journal, 1994Co-Authors: Ingram Schulze-neick, Gerd Hausdorf, Peter E. LangeAbstract:In a patient with Pulmonary Valve Atresia with hypoplastic main Pulmonary artery selective angiography showed absence of the central left Pulmonary artery and a right Pulmonary artery originating from the ascending aorta close to the left coronary artery. This unusual anatomical arrangement complicates interventional and surgical treatment.
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Catheter creation of an open outflow tract in previously atretic right ventricular outflow tract associated with ventricular septal defect.
The American journal of cardiology, 1993Co-Authors: Gerd Hausdorf, Martin Schneider, Peter LangeAbstract:Abstract Pulmonary Atresia with ventricular septal defect is a therapeutic challenge. Surgical creation of an aorto-Pulmonary shunt, or palliative light ventricular (RV) outflow tract reconstruction is performed to increase Pulmonary perfusion. 1–3 Recently, transcatheter perforation, using a hot-up laser, and subsequent balloon dilatation was reported in Pulmonary Valve Atresia. 4 The interventional creation of a “neo-lumen” within a muscular RV Atresia has been suggested to be beyond the scope of interventional cardiology. We report the results of radiofrequency perforation in 10 patients with muscular Atresia of the RV outflow tract.
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Pulmonary Valve Atresia with ventricular septum defect: interventional recanalization of the right ventricular outflow tract
Zeitschrift fur Kardiologie, 1992Co-Authors: Gerd Hausdorf, Ingram Schulze-neick, M. Schneider, Peter E. LangeAbstract:A case of Pulmonary Atresia with ventricular septal defect is reported where continuity between the right ventricle and the hypoplastic Pulmonary artery was established interventionally. The atretic Valve was perforated using a special "perforation needle" with a sharp and stiff distal and a flexible proximal part. Perforation of the bifurcation was well tolerated without later sequelae. After perforation of the Atresia, dilation was successfully performed using 2, 4, and 7.2 mm balloons with a pressure of 10 atm; the arterial oxygen saturation increased from 72% to 84%. Four weeks later repeated "valvuloplasty" was performed (balloon diameters 8 mm, 9.5 mm, and 12 mm) and the "Valve" ring was dilated to a diameter of 10.5 mm. Although no general conclusions can be drawn from this single application, mechanical perforation of the Atresia could become an attractive interventional approach for the treatment of Pulmonary Atresia.
Lee N. Benson - One of the best experts on this subject based on the ideXlab platform.
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Transcatheter perforation of the right ventricular outflow tract as initial therapy for Pulmonary Valve Atresia and intact ventricular septum in the newborn
Catheterization and cardiovascular diagnosis, 1997Co-Authors: Robert N. Justo, David Nykanen, William G. Williams, Robert M. Freedom, Lee N. BensonAbstract:The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow tract in neonates with Pulmonary Atresia and intact ventricular septum was reviewed. Between April 1992 and December 1994, 8 neonates underwent transcatheter perforation of the right ventricular outflow tract. Radiofrequency energy was employed in 6 patients and wire perforation in 2 patients. Mean patient age at intervention was 1.9 +/- 0.6 days and weight 3.4 +/- 0.5 kg. Median tricuspid Valve annulus was 10.9 mm (range: 4.0-13.0 mm) and Z-value -0.85 (range: -4.5-1.0). The mean right ventricular systolic pressure fell from 117 +/- 16 to 55 +/- 15 mm Hg (P < 0.0001), and the right ventricular to aortic pressure ratio decreased from 1.81 +/- 0.33 to 0.82 +/- 0.28 (P < 0.0001). The arterial duct was patent in all. No acute complications occurred. AortoPulmonary shunts were performed in 7 patients at a median 6 days (range: 3-23 days) following catheterization. One patient developed sepsis and died after surgical resection of infected tissue, while a second patient died of a blocked aortoPulmonary shunt 17 months following discharge. Median follow-up for the 6 surviving patients was 8 months (range: 4-32 months). One patient has achieved and a second is awaiting biventricular repair. Transcatheter perforation appears to be a promising form of therapy in selected patients with Pulmonary Atresia, and potentially facilitates algorithms leading to a biventricular repair.
