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Introduction Cardiopulmonary bypass components need to be tested on an animal model before their clinical application. Because their weight is similar to that of man, the calf and pig are often used. This study compares the impact of prolonged perfusion on hemolysis and hematology profile in both species. Methods Three calves (mean bodyweight: 77.2±4.4 kg) and three pigs (80±5.3 kg) were connected to an extracorporeal circulation circuit by jugular venous and carotid arterial cannulation, with a mean flow rate of 3.5L/min for 6h. After 7 days, the animals were sacrificed. A standard battery of blood samples was taken before, throughout, and 24h, 48h and 7 days after bypass. ANOVA was used for repeated measurements. Results Absolute values of red cell count were higher in the calf (pConclusions In the setting of prolonged perfusion, species type - bovine or porcine - has an impact on hematology profile, but not on hemolytic parameters. These findings should be taken into account when cardiopulmonary bypass components are tested.

La coarctation de l'aorte est de nos jours rarement observée chez les patients adultes, cette pathologie étant généralement détectée et corrigée chirurgicalement durant la petite enfance. Non traitée, la maladie conduit au développement d'une hypertension artérielle (HTA) importante et l'évolution naturelle amène souvent au décès précoce. Nous rapportons les cas de 3 patients de plus de 30 ans, récemment opérés dans nos services, de coarctation aortique non détectées auparavant. Dans 2 cas, il s'agissait de ressortissants étrangers, de 46 et 32 ans, chez qui l'examen médical a mis en évidence une hypertension artérielle et l'absence de pouls palpables aux membres inférieurs. Le 3ème patient, suisse de 33 ans, présentait un examen clinique similaire. Dans les 3 situations, la radio du thorax montrait des érosions costales évidentes et le diagnostic suspecté de coarctation a été confirmé par l'angiographie. 3 techniques chirurgicales différentes ont été employées, selon la situation per-opératoire. Dans un cas, la résection de la sténose a pu être suivie d'une anastomose termino-terminale directe. Chez un patient, l'obstacle était complet et s'étendait sur 3cm. Le segment réséqué a été remplacé par une prothèse de Dacron. Dans le 3ème cas, nous avons opté pour une plastie d'élargissement par patch synthétique. A chaque fois, les suites opératoires ont été simples et dans tous les cas, les pouls étaient à nouveau palpables aux niveaux des artères fémorales. Malgré l'âge parfois avancé, il faut se rappeler de la possibilité d'une coarctation de l'aorte chez un patient sévèrement hypertendu, sachant que le bénéfice du traitement chirurgical est certain.

Les effets morphologiques et fonctionnels de la revascularisation transmyocardique au laser (RTML) sont analysés en conditions aiguës sur un modèle porcin. La paroi latérale du ventricule gauche de 15 porcs (poids moyen: 73 +/- 4kg) a été percée de 10 canaux laser (laser: Ho-YAG; longueur d'onde: 2.1 u, diamètre de la sonde: 1.75 mm). Une échocardiographie a été effectuée avant, ainsi que 5 min et 30 min après la procédure. Les paramètres échocardiographiques ont été enregistrés en court axe à la hauteur des canaux laser. Ils comprenaient la fraction d'éjection, la fraction de raccourcissement et la motilité segmentaire de la région lasérisée (échelle de 0 à 3: 0 = normal, 1 = hypokinésie, 2 = akinésie, 3 = dyskinésie). Après sacrifice de l'animal, la région lasérisée a été coupée dans un plan perpendiculaire aux canaux pour histologie et analyse morphométrique. Après 5 min, tous les index échocardiographiques ont montré une aggravation significative par rapport aux valeurs de base (p < 0.01). Après 30 min, plus aucun des paramètres ne présentait de variation significative par rapport aux valeurs de base. La surface de section des lésions mesurait 8.8 +/- 2.4 mm2 soit plus du triple de celle de la sonde laser elle-même (p < 0.01). En conditions aiguës, les lésions dues à la sonde de RTML sont nettement plus grande que la sonde elle-même et entraînent une baisse transitoire de la contractilité segmentaire sur un coeur sain. Ces résultats suggèrent que la RTML doit être utilisée avec prudence en clinique chez les patients avec une mauvaise fonction ventriculaire.

BACKGROUND: The impact of preoperative impaired left ventricular ejection fraction (EF) in octogenarians following coronary bypass surgery on short-term survival was evaluated in this study. METHODS: A total of 147 octogenarians (mean age 82.1 ± 1.9 years) with coronary artery diseases underwent elective coronary artery bypass graft between January 2000 and December 2009. Patients were stratified into: Group I (n = 59) with EF >50%, Group II (n = 59) with 50% > EF >30% and in Group III (n = 29) with 30% > EF. RESULTS: There was no difference among the three groups regarding incidence of COPD, renal failure, congestive heart failure, diabetes, and preoperative cerebrovascular events. Postoperative atrial fibrillation was the sole independent predictive factor for in-hospital mortality (odds ratio (OR), 18.1); this was 8.5% in Group I, 15.3% in Group II and 10.3% in Group III. Independent predictive factors for mortality during follow up were: decrease of EF during follow-up for more that 5% (OR, 5.2), usage of left internal mammary artery as free graft (OR, 18.1), and EF in follow-up lower than 40% (OR, 4.8). CONCLUSIONS: The results herein suggest acceptable in-hospital as well short-term mortality in octogenarians with impaired EF following coronary artery bypass grafting (CABG) and are comparable to recent literature where the mortality of younger patients was up to 15% and short-term mortality up to 40%, respectively. Accordingly, we can also state that in an octogenarian cohort with impaired EF, CABG is a viable treatment with acceptable mortality.

To evaluate the thromboresistant properties of phospholipidic surface coatings mimicking the lipid surface of blood cells, we studied four different types of phospholipids bound onto PVC tubings in comparison to uncoated as well as heparin bonded controls. The samples analyzed included diacetylenic phospholipid coated as a monomeric treatment (A), diacetylenic phospholipid polymerised prior to being coated (B), and two types of polymeric phospholipids made using methacrylate containing monomers (C and D). A bovine (bodyweight 67 ± 3 kg) left heart bypass model (pump flow 3.2 ±0.1 l/min) was selected and the surfaces were exposed to the blood stream up to 360 min without systemic heparinization. Thereafter another set of samples was exposed to stagnant blood over 20 min. Besides hemodynamic, hematologic and biochemical analyses, the macroscopic appearance of 119 blood exposed surface samples was graded semiquantitatively on a scale of 0 to 10: no macroscopic deposits = grade 0, 1 spot (1 mm diameter) = grade 1, 2 spots = grade 2, 5 or more spots = grade 5, up to 10% of the surface covered with clots = grade 6, 100% covered = grade 10 (p

Objective: Atrial fibrillation is a very common heart arrhythmia, associated with a five-fold increase in the risk of embolic strokes. Treatment strategies encompass palliative drugs or surgical procedures all of which can restore sinus rhythm. Unfortunately, atria often fail to recover their mechanical function and patients therefore require lifelong anticoagulation therapy. A motorless volume displacing device (Atripump ® ) based on artificial muscle technology, positioned on the external surface of atrium could avoid the need of oral anticoagulation and its haemorrhagic complications. An animal study was conducted in order to assess the haemodynamic effects that such a pump could provide. Methods: Atripump is a dome-shape siliconecoated nitinol actuator sewn on the external surface of the atrium. It is driven by a pacemaker-like control unit. Five non-anticoagulated sheep were selected for this experiment. The right atrium was surgically exposed, the device sutured and connected. Haemodynamic parameters and intracardiac ultrasound (ICUS) data were recorded in each animal and under three conditions; baseline; atrial fibrillation (AF); atripump assisted AF (aaAF). Results: In two animals, after 20 min of AF, small thrombi appeared in the right atrial appendix and were washed out once the pump was turned on. Assistance also enhanced atrial ejection fraction. 31% baseline; 5% during AF; 20% under aaAF. Right atrial systolic surfaces (cm 2 ) were; 5.2 ± 0.3 baseline; 6.2 ± 0.1 AF; 5.4 ± 0.3 aaAF. Conclusion: This compact and reliable pump seems to restore the atrial “kick” and prevents embolic events. It could avoid long-term anticoagulation therapy and open new hopes in the care of end-stage heart failure. Summary

Between 1978 and 1990 emergency pulmonary embolectomy with the aid of extracorporeal circulation (ECC) was performed for massive pulmonary embolism (PE) in 44 patients (19-73 yrs; 49 +/- 15 yrs). Cardiopulmonary circulation was stable in 16/44 patients but unstable in 28/44; of the latter, 15 had undergone previous cardiopulmonary resuscitation due to cardiac arrest. Diagnosis of PE was obtained clinically in 15/44 patients, by angiography in 13/44, by echocardiography in 10/44, and by perfusion scintigraphy of the lung in 6/44 patients. There were 9/44 (20%) postoperative deaths. Early mortality was significantly higher in previously resuscitated patients (p less than 0.05). There were 2/36 (6%) late deaths. Actuarial survival was 75% after 4 yrs and 71% after 8 yrs. 77% or 35 survivors were in NYHA-class I and 23% in NYHA-class II after a mean follow-up of 4.6 yrs. Pulmonary embolectomy is indicated in patients with central PE and shock; it is advisable in patients with embolism of the main pulmonary artery or its major branches or in patients with contraindication to thrombolysis. Intraoperative insertion of a vena cava filter is recommended for prevention of recurrent embolism. Preoperative resuscitation and duration of ECC are predictors for early death.

Heparin surface coating is one approach to improve the biocompatibility of existing blood pumps used for mechanical circulatory support. Experimental evaluation of centrifugal pumps with heparin surface coating was performed during open chest left heart bypass (3.7 L/min over 6 hours) in two series of bovine experiments. Eight calves (74 +/- 4 kg) were perfused either by heparin surface coated equipment without systemic heparinization or uncoated equipment with systemic heparinization (300 I. U,/kg bodyweight; ACT greater than 400 s). A standard battery of analyses was performed before and at regular intervals after onset of perfusion. At the end of perfusion all pump-heads were gently rinsed. There were no macroscopic clots for both groups whereas macroscopic clots were observed in uncoated tubings introduced for control in the group perfused without systemic heparinization. The hemodynamics were significantly better in the group perfused without systemic heparinization and maintained functional coagulation system. Clinical application of heparin surface coated equipment during resection of thoraco-abdominal aortic aneurysms is showing promising results in 12 patients.

OBJECTIVES: The off-pump trans left ventricular approach provides an alternative option for insertion of stented aortic valves of any size for endovascular replacement. One of the key steps in this procedure is the repair of the ventricle after catheter withdrawal. This study evaluates the reliability of a new device for sutureless and quick repair of the left ventricle access. METHODS: The Amplatz-nitinol occluder consists of two square heads that squeeze the ventricle wall between them thus sealing the ventricular defect. In four adult pigs weighing 55 kg, left thoracoscopy was performed to open the pericardium and visualise the cardiac apex. Following a heparin injection (100 U/kg) under ICUS and fluoroscopic control, we inserted a 30 F sheath into the epigastric area through the cardiac apex up into the left ventricle thus simulating the approach for an off-pump aortic valve replacement. The sheath was then removed and the ventricle closed with the occluder. Animals were followed-up for three hours; the haemodynamics and pericardial bleeding were recorded. The animals were then sacrificed and the gross anatomy of the heart was examined. RESULTS: The device was successfully deployed in four animals in less than one minute. ACT was above 200 seconds in all cases. All animals survived the procedure with a mean arterial pressure of 50 +/- 15 mm Hg. Bleeding during deployment was 80 +/- 20 ml and over a 3 hour period was 800 +/- 20 ml. Examination of the gross anatomy examination demonstrated the correct positioning of the device. CONCLUSIONS: The occluder is easy to use and the procedure is feasible and reproducible. However, the occluder design requires technical improvements in order to reduce bleeding before it can be used clinically.

Patients with Ebstein's anomaly can present after childhood or adolescence with cyanosis, arrhythmias, severe right ventricular dysfunction and frequently with left ventricular dysfunction secondary to the prolonged cyanosis and to the right ventricular interference. At this point conventional repair is accompanied by elevated mortality and morbidity and poor functional results. We report our experience with three patients (8, 16 and 35 years of age) with Ebstein's anomaly, very dilated right atrium, severe tricuspid valve regurgitation (4/4), bi-directional shunt through an atrial septal defect and reduced left ventricular function (mean ejection fraction = 58%, mean shortening fraction = 25%). All underwent one and a half ventricular repair consisting of closure of the atrial septal defect, tricuspid repair with reduction of the atrialised portion of the right ventricle and end-to-side anastomosis of the superior vena cava to the right pulmonary artery. All patients survived, with a mean follow-up of 33 months. In all there was complete regression of the cyanosis and of the signs of heart failure. Postoperative echocardiography showed reduced degree of tricuspid regurgitation (2/4) and improvement of the left ventricular function (mean ejection fraction = 77%, mean shortening fraction = 40%). In patients with Ebstein's anomaly referred late for surgery with severely compromised right ventricular function or even with reduced biventricular function, the presence of a relatively hypoplastic and/or malfunctioning right ventricular chamber inadequate to sustain the entire systemic venous return but capable of managing part of the systemic venous return, permits a one and a half ventricular repair with good functional results.

The indication for pulmonary artery banding is currently limited by several factors. Previous attempts have failed to produce adjustable pulmonary artery banding with reliable external regulation. An implantable, telemetrically controlled, battery-free device (FloWatch) developed by EndoArt SA, a medical company established in Lausanne, Switzerland, for externally adjustable pulmonary artery banding was evaluated on minipigs and proved to be effective for up to 6 months. The first human implant was performed on a girl with complete atrioventricular septal defect with unbalanced ventricles, large patent ductus arteriosus and pulmonary hypertension. At one month of age she underwent closure of the patent ductus arteriosus and FloWatch implantation around the pulmonary artery through conventional left thoracotomy. The surgical procedure was rapid and uneventful. During the entire postoperative period bedside adjustments (narrowing or release of pulmonary artery banding with echocardiographic assessment) were repeatedly required to maintain an adequate pressure gradient. The early clinical results demonstrated the clinical benefits of unlimited external telemetric adjustments. The next step will be a multi-centre clinical trial to confirm the early results and adapt therapeutic strategies to this promising technology.

Myocardial angiogenesis induction with vascular growth factors constitutes a potential strategy for patients whose coronary artery disease is refractory to conventional treatment. The importance of angiogenesis in bone formation has led to the development of growth factors derived from bovine bone protein. Twelve pigs (mean weight, 73 +/- 3 kg) were chosen for the study. In the first group (n = 6, growth factor group) five 100 micrograms boluses of growth factors derived from bovine bone protein, diluted in Povidone 5%, were injected in the lateral wall of the left ventricle. In the second group (n = 6, control group), the same operation was performed but only the diluting agent was injected. All the animals were sacrificed after 28 days and the vascular density of the left lateral wall (expressed as the number of vascular structures per mm2) as well as the area of blood vessel profiles per myocardial area analysed were determined histologically with a computerised system. The growth factor group had a capillary density which was significantly higher than that of the control group: 12.6 +/- 0.9/mm2 vs 4.8 +/- 0.5/mm2 (p < 0.01). The same holds true for the arteriolar density: 1 +/- 0.2/mm2 vs 0.3 +/- 0.1/mm2 (p < 0.01). The surface ratios of blood vessel profiles per myocardial area were 4900 +/- 800 micron 2/mm2 and 1550 +/- 400 micron 2/mm2 (p < 0.01) respectively. In this experimental model, bovine bone protein derived growth factors induce a significant neovascularisation in healthy myocardium, and appear therefore as promising candidates for therapeutic angiogenesis.

A 19-day-old boy with Ivemark syndrome (splenic agenesis associated with complex cardiac malformations and visceral abnormality) underwent palliative surgery including Glenn and hemi-Fontan procedures. Five months later the child is alive and well. We believe that early palliative surgery is worthwhile in Ivemark syndrome with a single ventricle.

Deep accidental hypothermia is an uncommon pathology. Successful management has been reported in isolated cases, but the majority of patients die from complications after rewarming. We report on a patient with deep accidental hypothermia after a mountaineering accident. He was successfully rewarmed with cardiopulmonary bypass, but presented several complications which led to death. These complications included the patient developing acute peritonitis and necrotizing fasciitis, which represent, to our knowledge, complications that have never been associated with deep accidental hypothermia before.

Atrioventricular (AV) valve dysfunction with tricuspid regurgitation is a common finding after orthotopic heart transplantation (HTx). In 20 patients the heart transplantation was performed with bicaval anastomoses and the results were compared to the precedent 20 patients operated with the standard technique. The right atrium of the recipient was completely removed and the caval anastomoses were performed on the beating heart during reperfusion. Using an interrupted suture line, no stenoses at the venous anastomoses were seen as known from the early implantation technique in heart-lung transplantation. Due to a more stable sinus rhythm only 15% of the patients in the bicaval group needed prolonged pacing (> 30 min) versus 55% (P < 0.01) in the group with standard operation. One to 3 months after surgery the transthoracic echocardiographic evaluation of the AV valve function showed tricuspid valve regurgitation (TVR) in 20% of the patients with bicaval anastomoses versus 75% with a right atrial anastomosis (P < 0.001). Tricuspid valve regurgitation during the first 2 weeks (in 31% of recipients with bicaval and in 70% with atrial anastomoses) improved in all recipients with bicaval anastomoses and in 14% of the recipients with atrial anastomosis. The modification of the operation technique did not result in significantly longer bypass time (75 +/- 14 versus 68 +/- 14 min) and ischemia time (44 +/- 12 versus 41 +/- 9 min with local organ procurement and 111 +/- 24 versus 101 +/- 19 min with distant organ procurement). The AV valve function and the postoperative rhythm after orthotopic HTx can be improved by implanting the heart with bicaval anastomoses.

Isolated anomalous origin of the right coronary artery (RCA) is a very rare congenital malformation. The case of a 15-month-old boy with anomalous origin of the RCA from the pulmonary artery is presented. The RCA was reimplanted into the aorta. The anatomical correction was uneventful and its success demonstrates that diagnosis and surgical correction are possible at a very young age.

Early and late results after surgery for isolated congenital valvar aortic stenosis were evaluated in a total of 86 children under 16 years of age (mean 7.4 years). Primary procedure was always conservative. There were 7/86 (8.1%) early deaths. All infants who died after the operation were younger than 4 months of age. Among the clinical variables tested by the univariate analysis only age and duration of cardiopulmonary bypass were significant prognostic factors for early death. There were 6/67 (7.7%) valve-related late deaths. Multivariate analysis could not identify any risk factors for early and late mortality. Actuarial survival was 97% (95% CL 93-101%) after 5 years, 94% (88-100%) after 10 years, 90% (82-98%) after 15 years, and 87% (77-97%) after 20 years. A total of 22/79 (28%) early survivors had a first reoperation and 5 had a second reoperation. Long follow-up interval was the only significant factor for reoperation. Actuarial reoperation-free interval was 91% (85-98%) after 5 years, 70% (58-81%) after 10 years, and 50% (34-64%) after 15 years. Significant factors for poor valve function were long duration of follow-up, endocarditis, and young age at operation. The probability of normal valve function was 91% (84-98%) after 5 years, 67% (55-79%) after 10 years, and 54% (40-68%) after 15 years.

Between 1970 and 1989 26 children were operated for pulmonary atresia with intact ventricular septum (PA/IVS). According to the degree of right heart hypoplasia the patients were divided into 3 groups of mild (5), moderate (17) or severe (4) hypoplasia. Palliative operations were performed in 25 children (17 male, 8 female) at a mean age of 10 days: 13 valvotomies (valv.), 5 aortopulmonary shunts, and 7 valv. plus shunt. One patient had total correction as primary procedure. A total of 17 reoperations was necessary in 12 of 26 patients (10 palliations, 7 total corrections). Total corrections were: 2 conduits and 5 patches of the right-ventricular outflow tract (RVOT). Total mortality was 14/26 (54%) children (early 10/26 = 38%, late 4/26 = 16%). After total correction mortality was 3/7 (43%) patients. After a mean follow up of 10.8 years after palliation the 12 survivors are mostly in NYHA class I. Actuarial survival after palliation was 60% after 30 days and 44% after 5 and 10 years. We analyzed 9 clinical and hemodynamic variables by univariate and multivariate analysis to assess the predictive factors of postoperative outcome. Multivariate analysis disclosed the degree of right-ventricular hypoplasia (p = 0.023) as an independent predictor for death whereas the age at palliation only approached significance (p = 0.065). We recommend the following surgical strategy, aiming in the first place at decompressing the right ventricle: in mild hypoplasia valvotomy alone or combined with a shunt for palliation, in moderate hypoplasia shunt plus patch of the RVOT and in severe hypoplasia shunting alone. In case of a restrictive foramen ovale initial balloon septostomy is performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term survival after atrial repair of a transposition of the great arteries between 1964 and 1988 is analyzed in 254 thirty-day survivors. For the complete series, overall survival is 99.6% after one year, 94.9% after 6 years, 89.6% after 12 years, 84.9% after 18 years, and 64.0% after 24 years. Broken down for simple (154/254) versus complex (95/254) transposition survival, it is 99.4% versus 100.0% for one year, 94.7% versus 99.5% for 6 years, 90.8% versus 88.3% for 12 years, 85.1% versus 85.8% for 18 years and 77.7% versus 46.8% at 24 years. Survival for patients without or with VSD is 95.3% versus 96.2% after 6 years, 91.2% versus 87.9% after 12 years, 87.5% versus 84.0% after 18 years, and 83.7% versus 52.5% after 24 years. Cumulative survival as a function of the surgical approach for VSD closure is 94.3% for transatrial versus 92.3% for transventricular at 6 years, 82.2% versus 92.3% after 12 years, 82.2% versus 83.0% after 18 years and 82.2% versus 41.5% after 24 years. Survival for patients operated upon before 1978 is 94.3% versus 96.0% thereafter at 6 years, and 90.7% versus 89.2% at 12 years (NS). Linearized mortality rates are 1.49% per patient year for the complete series, 0.93 for simple transpositions, 2.21% for complex transpositions (including VSD, obstruction of the left ventricular outflow tract, or both), 0.68% for transpositions without VSD, 1.98% for transpositions with VSD, 2.43% for transposition with transventricular repair of a VSD, 1.74% for transposition with transatrial closure of a VSD, and 0.90% for all cases operated upon after 1978.(ABSTRACT TRUNCATED AT 250 WORDS)

Pseudoaneurysm formation after aortic homograft replacement in patients with active endocarditis is a common observation and usually occurs at the site of a former abscess or paravalvular leak in case of prosthetic valve endocarditis. A 53-year-old man with prosthetic endocarditis underwent aortic valve homograft replacement and developed a pseudoaneurysm at the right and noncoronary aortic sinus which was documented by Doppler echocardiography. Follow-up examination ten months after operation unexpectedly revealed a complete obliteration of the previously echo free space between the homograft and the native aortic root and, thus, spontaneous obliteration of the pseudoaneurysm.