The left retro-aortic brachiocephalic vein: morphologic data and diagnostic ultrasound in 27 cases.

A left retro-aortic brachiocephalic vein is a rare anatomic entity. A retrospective study was made of 5218 congenital cardiopathies treated between 1982 and 1998 in a medico-surgical department of paediatric cardiology. A left retro-aortic brachiocephalic vein was demonstrated in 27 patients, i.e. an incidence of 0.5%. The chief cardiopathy in these patients was a tetralogy of Fallot in 25 cases (93%). Among these 25 cases of Fallot's tetralogy the aortic arch was rightsided in 19 cases (70%). The paraclinical diagnosis of this anomaly was facilitated by ultrasonography, provided it was sought for. In this series 6 cases (22%) were discovered during surgery without previous ultrasound diagnosis. The embryological origin of the left retro-aortic brachiocephalic v. differs from that of the venous trunk in its classical anatomic form. It derives from the inferior (but not superior) transverse plexuses, connecting the two anterior cardinal veins. One of the main consequences of this anomaly is its possible confusion with other vascular structures, particularly the right pulmonary artery. Such confusion may give rise to inappropriate surgical procedures. The differential diagnosis is facilitated by the use of the Doppler: the venous flow is biphasic and regulated by respiration, whereas the Doppler recording from a pulmonary artery is that of a characteristic systolic arterial flow.

Long-term clinical and hemodynamic evaluation of porcine valved conduits implanted from the right ventricle to the pulmonary artery.

OBJECTIVE: This retrospective study was initiated to evaluate the long-term results of valved prosthetic conduits implanted in the right ventricular outflow tract in patients with complex ventricular-pulmonary discontinuity. METHODS: A cohort of 103 patients out of 127 (24 early deaths, 19%) operated on between 1973 and 1996 with porcine valved conduits was available for evaluation, with a follow-up ranging from 1 to 21.6 years (mean follow-up 8.4 +/- 6 years). A total of 74 hemodynamic studies were performed after the operation, 50 patients having undergone at least 1 cardiac catheterization during the follow-up period. RESULTS: There were 16 late deaths, and the actuarial survivals, including early mortality, were 72.9% +/- 4% at 5 years, 63.1% +/- 5% at 10 years, and 58.2% +/- 5% at 15 years, at which time 20 patients were still available for review and exposed to the risk of dying. The mean peak systolic gradient across the right ventricular outflow tract was plotted as a function of time, showing a gradual increase and a significant step-up after the eighth year, from 43 +/- 36 to 69 +/- 19 mm Hg (P < .005). Reoperation was required for progressive conduit obstruction between 1.1 and 17.7 years after implantation (mean 7.4 +/- 4.8 years) in 25 patients (24%, 70% CL 15%-33%), with generally very few symptoms, or for residual ventricular septal defect in 3 patients. Freedom from reoperation was 79.5% +/- 5% at 10 years and 65.8% +/- 7% at 15 years. CONCLUSIONS: Porcine conduits may represent a valuable alternative to biologic substitutes with similar long-term results. Given the few symptoms, progressive conduit stenosis after the eighth postoperative year imposes a yearly noninvasive patient evaluation during the follow-up.

The hemodynamic effects of hypoxemia in anesthetized pigs: a comparison between right heart catheter and echocardiography.

UNLABELLED: During hypoxemia, hypoxic pulmonary vasoconstriction and tachycardia are often observed in association with increases in pulmonary artery pressure and cardiac output. Nevertheless, the hemodynamic consequences of hypoxemia have never been evaluated by echocardiography and simultaneously compared with invasive hemodynamic variables. Fourteen open-chest, anesthetized piglets (weight 29-36 kg) were submitted to progressive hypoxemia and reoxygenation. Usual invasive hemodynamic variables were obtained from peripheral and central heart catheters. Direct epicardial echocardiography was used to measure right and left ventricular areas on a short-axis view at mid-papillary level. The mean pulmonary artery pressure (MPAP) increased with pulmonary vascular resistance in a dose-related manner as the fraction of inspired oxygen (FIO2) declined from 0.5 to 0.12. The MPAP correlated with right ventricular end-diastolic area (RVEDA) only at FIO2 0.08. There was a 49% reduction in left ventricular end systolic wall stress (LVESWS) between FIO2 0.5 and 0.08. Left ventricular ejection fraction area (LVEFA) increased by 33% above baseline and correlated with the decrease in LVESWS. No correlation was observed between left ventricular end-diastolic area and pulmonary artery occlusion pressure or left atrial pressure and between cardiac output and LVEFA. Systemic vascular resistance underestimates the magnitude of changes in LVESWS but overestimates the afterload compared with LVESWS. This study demonstrates that, for the lowest FIO2 (0.08), changes in MPAP correlated with changes in RVEDA but not in pulmonary vascular resistance. Moreover, LVESWS decreases significantly in a dose-related manner under progressive hypoxemia and normalizes immediately after reoxygenation. This study also shows that, under hypoxemic conditions, echocardiography enhances understanding of hemodynamic changes compared with right heart catheterization alone. IMPLICATIONS: Acute hypoxemia in pigs is responsible for pulmonary vasoconstriction-induced pulmonary hypertension (which is restricted by the right ventricular failure), as well as a PaO2-dependent decrease in left ventricular afterload. These changes are better displayed by echocardiography than by right heart catheter.

Experimental right ventricle to pulmonary artery discontinuity: outcome of polyurethane valved conduits.

OBJECTIVE: The ideal substitute for the treatment of ventricle-pulmonary artery discontinuity remains a topic of controversy, because of calcifications and degeneration of biologic substitutes leading to subsequent reoperations. Because polyurethane valves used in ventricular assist devices show a satisfactory biocompatibility, the aim of this study was to evaluate a valved conduit composed of a Dacron graft incorporating a trileaflet 25 mm polyurethane valve. METHODS: The conduit was implanted between the right ventricle and the main pulmonary artery in adult sheep, with ligation of the proximal pulmonary artery. The animals received no medications. Serial hemodynamic data were collected at the time of implantation and at postoperative intervals of 6 and 12 months. RESULTS: The peak pressure gradient across the valve increased significantly between implantation (0.17 +/- 5.6 mm Hg) and 6 months after operation (7.3 +/- 3 mm Hg, p = 0.0007) and remained stable thereafter (6.7 +/- 3 mm Hg at 12 months), whereas the cardiac output remained unchanged (4.6 +/- 0.6 L/min at implantation, 4 +/- 0.6 L/min at 6 months, and 3.9 +/- 1.1 L/min at 12 months). At the completion of the study, valve samples were processed and vapor coated with carbon for microscopic examination. There was one instance of nonadherent thrombus formation inside a cusp but no structural failures. The other valves were free of calcium deposits and no significant amounts of phosphorus could be detected by scanning electron microscopy and energy dispersive spectrometry. CONCLUSIONS: These data demonstrate the good hemodynamic performance, low thrombogenicity, and acceptable durability of the polyurethane valves implanted in the right side of the heart in a chronic sheep model.

Mechanical versus biological isolated aortic valvular replacement after the age of 70: equivalent long-term results.

OBJECTIVE: In order to evaluate the long-term outcome of valvular substitutes in the elderly, we retrospectively analyzed two comparative groups of patients consecutively operated on by the same team for an isolated valvular aortic replacement using either a mechanical or a pericardial prosthesis. METHODS: From 1982 to 1996, 206 patients over 70 years (mean 76.5+/-4.4) underwent an isolated aortic valvular replacement using either a St. Jude Medical (Group I, n = 93) or a Mitroflow (Group II, n= 113) prosthesis depending on the surgeon's preference at the time of surgery. Both groups matched for the following pre-operative variables: sex ratio, type of aortic valve disease, NYHA status, cardiac rhythm, mean pulmonary arterial pressure, left ventricular end-diastolic pressure, LV-AO gradient, cardiac index and ejection fraction. RESULTS: Given an early mortality rate of 6.4% in Group I and 4.4% in Group II (NS), follow-up (mean 4.4+/-3.7 years in Group I and 5.3+/-3.1 years in Group II) was 100% complete. Actuarial survival was 69.9+/-6 and 70.2+/-4.6% at 5 years for Group I and Group II, respectively, and 49.6+/-7.7 vs. 51.4+/-6.3% at 10 years (NS). Freedom from valve-related death was 86.5+/-4.8% in Group I vs. 82.7+/-4% in Group II at 5 years (NS) and 66.7+/-8.7 vs. 66.3+/-7% at 10 years (NS). There were no anticoagulant-related deaths or severe accidents in Group 1. A secondary valvular replacement was necessary in 4 patients in Group II vs. none in Group I. CONCLUSION: The study shows a similar late survival in both groups, with a strikingly low incidence of anticoagulant-related deaths in this population. Given a higher rate of reoperation after biological valve replacement, the use of mechanical valve in this aging population seems to be a valid option.

Malignant neoplasms following cardiac transplantation.

OBJECTIVE: Malignancies have long been recognized as a complication of long lasting immunosuppressive therapy. We reviewed our experience to investigate the incidence and the spectrum of non cutaneous de novo malignant neoplasms. METHODS: Between March 1987 and March 1996, 296 patients underwent 303 cardiac transplantation in our service. The population at risk consists of all patients surviving more than 1 month after transplantation, leading to a total of 267 patients. A triple-immunosuppressive therapy was employed. Moderate doses of antilymphocyte globulin was used as an induction immunotherapy. RESULTS: Neoplasms developed in 18 (6.7%) of the 267 patients at risk. Seventeen patients were male. Mean age was 56 +/- 7 years. Fourteen patients (78%) reported a significant smoking history. Mean interval between transplantation and clinical diagnosis was 36 months. Lung neoplasms (especially adenocarcinoma) were the most commonly encountered tumors (11 of 268 patients, 4.1%). Three Non-Hodgkins' Lymphoma (NHL) were identified (1.1%). No Kaposi's sarcoma were diagnosed. Mean survival after a diagnostic of tumor was 11.7 months. CONCLUSIONS: The incidence of NHL is low in our transplant recipients. Conversely, we observed a high incidence of lung neoplasms (especially adenocarcinoma) which can be correlated with a heavy cigarette use in the study population.

Repopulation of freeze-dried porcine valves with human fibroblasts and endothelial cells.

BACKGROUND AND AIMS OF THE STUDY: There is a need for a replacement cardiac valve constructed from non-immunogenic materials but incorporating living, and preferably autologous, cells. The object of this study was to colonize freeze-dried porcine valve leaflets with human fibroblasts and vascular endothelial cells. METHODS: Porcine pulmonary valve leaflets were freeze-dried to produce a porous matrix having communicating cavities of appropriate dimensions for fibroblast repopulation. Cultured human fibroblasts and vascular endothelial cells that had been cryopreserved by standard methods were added to freeze-dried leaflets. Following culture at 37 degrees C, the leaflets were examined by confocal scanning microscopy and transmission electron microscopy. RESULTS: Mechanical perforation of the leaflet surface permitted colonization of the freeze-dried matrix by fibroblasts; under the conditions we studied, the cell density did not reach physiologic levels but those cells that were present were well attached and metabolically active. Gentle cotton abrasion of the surface of the freeze-dried leaflets provided a suitable substrate for endothelial cell attachment and confluence was achieved in 10 days. Leaflets were perforated, cultured with human fibroblasts for 10 days, then gently rubbed with a cotton bud and cultured for a further 10 days with human endothelial cells. The endothelial cells formed a confluent layer on the surface and viable fibroblasts were present within the substance of the leaflet. CONCLUSION: Although these results are preliminary, they demonstrate the basic feasibility of this approach to the production of xenogeneic valves that contain the patient's own cells.

[Left ventricular assistance by postoperative mechanical devices in neonates]. / Réentraînement ventriculaire gauche par assistance mécanique postopératoire chez le nouveau-né.

Circulatory assistance in children and neonates has not been extensively reported. It poses specific problems related mainly to miniaturisation of systems. The authors report three cases of left ventricular assistance with the Biomedicus centrifugal pump followed by functional recovery in neonates operated for d-transposition of the great arteries. The assistance was installed by cannulation of the left atrial appendage and the ascending aorta, the canules being connected to the Biomedicus pump. The duration of assistance was 53, 116 and 120 hours respectively. The beginning of left ventricular recovery was observed after 24, 48 and 70 hours of assistance and the patients were weaned of assistance under stable haemodynamic conditions. One of the major problems during the period of assistance is decoagulation, 2 out of 3 patients requiring removal of thrombi during the first 12 hours of assistance. On the other hand, no cases of systemic embolism or thrombosis in the pump itself were observed. Decoagulation was maintained by continuous intravenous heparin with an initial dosage of 5 U/kg/h adapted to the activated cephalin time and anti Xa levels measured every 6 hours. No infectious complication was observed and the sternal wound healed satisfactorily despite systematic delayed closure of the thorax. The quality of results requires cooperation of a surgical infrastructure used to techniques of circulatory assistance, a well equipped neonatal intensive care unit and a permanently accessible laboratory for monitoring coagulation status.

Freeze drying of cardiac valves in preparation for cellular repopulation.

When freeze-dried cardiac valves have been implanted they remained acellular. This study is the initial step in the development of a method designed to repopulate the substance of the freeze-dried valve with fibroblasts and the lumenal surface with endothelial cells. In this scheme, the freeze-drying process performs three functions; it provides a porous matrix, it kills the donor cells, and it preserves the collagen structure and hence the mechanical strength of the valve. This paper describes the production of appropriate porosity in freeze-dried porcine pulmonary valve leaflets. We found that Tg' for this material is -83 degrees C, which made it impracticable to freeze-dry exclusively from the glassy state. Uncontrolled freeze-drying produced a variable structure with most of the pores considerably smaller than the desired size and a dense layer, apparently devoid of perforations, on the surface. Compacted layers also occurred within the substance of the leaflets. These appearances suggested that extensive collapse had occurred during the drying process. Variation of the cooling rate, the primary drying temperature, and the warming rate during secondary drying enabled us to identify the following conditions that provided satisfactory internal porosity: cooling at 5 degrees C/min, vacuum drying for 6 h at -20 degrees C, and secondary drying for 10 h during rewarming at 0.06-0.08 degrees C/min. The internal cavities measured 100-350 microns2 by ca. 400 microns2, which is adequate to provide access for the fibroblasts (cross-sectional area ca. 150-200 microns2 when rounded but fusiform when attached. However, the internal porous structure rarely communicated with the surface and mechanical perforation was required to provide continuity between the surface and the internal sponge. The resulting method provides a basis for studies of cell colonization.

Mechanical valve in aortic position is a valid option in children and adolescents.

OBJECTIVE: The choice of a valve substitute remains a challenge in young patients, with numerous reports of early degeneration and calcification of biological valves in this age group. Therefore an assessment of the long-term results after mechanical aortic valve replacement in children was initiated. METHODS: A retrospective study was conducted in 54 consecutive patients aged 1.1 to 17 years (mean 12.8 +/- 4 years) operated on between 1975 and 1993. Aetiology was congenital in 34 patients, rheumatic in 13, infectious in 5, and dystrophic in 2. Concomitant surgery included mitral valve replacement (10), aortic annulus enlargement (9), correction of truncus arteriosus (7), Bentall operation (2), coarctation repair (2), tricuspid valvuloplasty (2), correction of double outlet right ventricle (1), and replacement of a right ventricle to pulmonary artery conduit (1). A Bjork-Shiley valve was implanted in 14 patients, and a St Jude Medical valve in 40. All patients were given Warfarin with a monthly INR control. Follow-up was completed through questionnaires mailed to referring physicians and direct clinical examination. RESULTS: Overall early mortality was 13% (7 cases), and 6% (2 cases) in the 32 patients operated on after 1984. Follow-up was complete in 45 survivors (2 lost to follow-up), with a total follow-up of 261 patient-years. There were 6 late deaths, 4 being cardiac and due to persistent LV dysfunction, and 2 valve-related, due respectively to major gastro-intestinal bleeding and massive thromboembolism. Linearized rates of valve thrombosis and anticoagulant-related hemorrhage were both 0.3% per patient-year. Actuarial survival rate was respectively 84.5% at 5 years and 70.2% at 10 years. Reoperation was necessary in 3 patients for recurrent LV outflow tract obstruction. One patient with severe LV dysfunction is awaiting a heart transplant. CONCLUSION: We conclude that the longterm outcome after mechanical aortic valve replacement in children and adolescents is satisfactory and comparable to currently available reports on biological substitutes. The mandatory anticoagulant therapy is well tolerated in this age group.

[Coarctation of the aorta and its surgical treatment]. / Coarctation et son traitement chirurgical.

Coarctation or isthmic stenosis of the aorta is defined as an abnormal obstruction situated at the junction of the aortic arch and the descending aorta near the site of ligamentus arteriosus. It is a common malformation representing 5 to 7.5% of all congenital heart diseases. Coarctation of the aorta is 2 to 3 times commoner in boys than in girls. Two clinical forms may be distinguished: asymptomatic isolated coarctation of childhood, the surgical treatment of which was first performed by Crafoord in 1944, and coarctation of the neonate and infant associated in over 2/3 of cases with other cardiovascular malformations, especially tubular hypoplasia of the aortic arch. The surgical correction of isolated coarctation is best performed between 6 months and 1 year of age in other to limit the incidence of residual hypertension. A modified Crafoord technique decreases the risk of restenosis and enables treatment of associated hypoplasia of the aortic arch in the same surgical procedure.

[Effect of fibrin glue on lymphostasis during lymph node excisions. Prospective randomized study in 40 patients]. / Efficacité d'une colle de fibrine sur la lymphostase au cours des curages ganglionnaires. Etude prospective randomisée sur 40 patients.

To evaluate the efficacy of fibrin glue for lymphostasis during axillary and inguinal lymph node removal, we conducted a prospective randomized study including 40 patients. Post-operative mortality and morbidity rates were not different throughout the 2 groups. However they were significant decreasement in drainage duration, in drainage quantity and in hospital duration in the group "with" fibrin when compared with the group "without".

[Causes of failure analysis after cardiac transplantation. From a consecutive series of 91 cases]. / Analyse des causes d'échec après transplantation cardiaque. D'après une série consécutive de 91 cas.

Ninety-three cardiac transplantations were carried out in 91 patients (2 retransplantations) between March 1st 1987 and November 1st 1989, in 84 adults and 7 children under 15 years of age. The indications were dilated cardiomyopathy (48%), ischemic cardiomyopathy (35%), decompensated valvular heart disease (11%), congenital heart disease (3%) and two cases of Uhl's anomaly. Twelve patients underwent transplantation after external circulatory assistance (13%), 11 patients after inscription on the list of extreme emergencies, and 68 on an elective basis (74%). The postoperative immunosuppressive protocol was triple therapy: Ciclosporine, Azathioprine and Prednisone. Three of the children died. The early adult mortality was 9 cases (10.7%). It was 8% in patients operated electively. Major infectious complications occurred in 10 patients (11%). Rejection was looked for by systematic endomyocardial biopsy and echocardiography. Three hundred and forty-nine biopsies were made. Thirty-five patients (44%) had no problems of rejection. Seventy-nine patients have now been followed up for an average of 19 months. There were 7 late deaths. Seventy seven per cent of the survivors are asymptomatic. Acute rejection and transplant dysfunction were the two main causes of early mortality after cardiac transplantation. Although the long-term prognosis is uncertain, the medium-term results are very encouraging.

[Saint-Jude Medical tricuspid prosthesis. Long-term clinical, biological and echocardiographic assessment]. / La prothèse Saint-Jude Médical en position tricuspidienne. Evaluations clinique, biologique et échographique à long terme.

Twenty-four patients with a Saint-Jude Medical tricuspid valve prosthesis, aged 5 to 77 years, were studied. The etiology of the tricuspid lesion was rhumatic in 17 cases, infectious in 4 cases, and congenital in the other 3. Fourteen patient (58%) had undergone previous valve surgery, 7 of whom had undergone tricuspid valve replacement (TVR) by a bioprosthesis. Three patients were operated on for the third time. The TVR was isolated (4 cases) or associated with aortic valve replacement (3 cases), mitral valve replacement (8 cases), double aortic and mitral valve replacement (7 cases), repair of a ventricular septal defect (VSD) (1 case) and radical treatment of a Wolff-Parkinson-White syndrome (WPW) in 1 case. There were 3 early deaths (12.5%). Eighteen of the 21 survivors were followed up clinically, biologically (detection of hemolysis) and by Doppler echocardiography for an average period of 45 months (range 10 to 96 months). The clinical benefit was clear cut. No embolic complications were observed and there were no cases of hemolysis. The mean resting tricuspid pressure gradient was 3.57 +/- 2.36 mmHg. The Saint-Jude Medical prosthesis would therefore seem to be a good alternative to other mechanical valve prosthesis in the tricuspid position and without the risk of valve degeneration associated with bioprosthesis.

[Treatment of ventriculo-pulmonary disconnections with prosthetic conduits. Long-term results]. / Traitement des discontinuités ventriculo-pulmonaires par utilisation d'un tube valvulé. Résultats à long terme.

Between 1973 and 1989, 81 consecutive patients aged 2 to 42 years old, with ventriculo-pulmonary discontinuity, were treated by implantation of prosthetic conduits. The initial pathology was Tetralogy of Fallot (33%), complete transposition of the great arteries (20%), truncus arteriosus (17%), double outlet right ventricle (17%) and atrioventricular discordance with L malposition of the great arteries (10%). The overall early mortality was 22% (18 cases) and 14% (5 cases) in the 36 patients operated after 1982. Sixty three patients were followed up for 3 months to 16 years; there were 8 late deaths which occurred spontaneously or at reoperation. Postoperative catheterisation was carried out in 33 cases; the average ventriculopulmonary systolic pressure gradient was 40 +/- 26 mmHg. Six patients were reoperated to change the conduit, on average 6 years +/- 23 months after the first operation. Five other patients underwent endoluminal dilatation of a stenosed conduit which delayed reoperation to change the conduit in 3 cases. Prosthetic conduits have been extensively used in patients with ventriculo-pulmonary discontinuity because they are readily available. However, because of progressive degradation of the prostheses between the 5th and 10th postoperative years, other therapeutic solutions should be considered, i.e. endoventricular repair when possible and, in other cases, the use of aortic homografts.

[Apico-aortic shunts. Indications, results]. / Les dérivations apico-aortiques. Indications--résultats.

Seven children or adolescents aged 8 to 20 years (average 13.5 years) underwent implantation of an apico-aortic conduit from 1980 to June 1989. Eleven previous operations under cardiopulmonary bypass had been performed. The indications were recurrence of muscular subaortic stenosis and/or congenital valvular stenosis in 3 cases, and stenotic, previously implanted aortic valve prosthesis of small calibre in 4 cases. The preoperative left ventricular-aortic systolic pressure gradient was between 70 and 130 mmHg. The first two patients had a bioprosthetic valvulation and the 5 succeeding patients a St Jude Medical mechanical prosthesis. The early and late mortality was nil. The average follow-up period is 5, 6 years at present (range 6 months to 9 years). One patient had to undergo repeat valve replacement after 5 years for degenerescence of the porcine bioprosthesis implanted in the conduit. No other complications related to the conduit or valve were observed. At the endpoint of the study all patients were asymptomatic without treatment. Control echocardiographic data showed normalisation of the indices of left ventricular function. Apico-aortic conduits would seem to be a safe and effective technique for the treatment of recurrent severe obstruction of the left ventricular outflow tract.