Marcelo Biscegli Jatene

Assessment of the pulmonary vascular blood supply in patients with pulmonary atresia, ventricular septal defect, and aortopulmonary collateral arteries

OBJECTIVE: To study the morphometric characteristics of the central pulmonary arteries and aortopulmonary collateral arteries by assessing the morphology of the pulmonary vascular blood supply, to determine their significance in surgical treatment. METHOD: From January 1990 to June 2001, 40 patients were studied. Those who had the complete cineangiocardiographic study prior to the first surgical intervention were included in the study. The morphometric characteristics of the central pulmonary arteries (PPAA) and aortopulmonary collateral arteries (APCA) were analyzed, as was the distribution of blood irrigation to the lungs. The following indices were calculated: pulmonary arterial index (PPAAI), aortopulmonary collateral arterial index (APCAI), and total neopulmonary arterial index (TNPAI = PPAAI + APCAI). The surgical treatment was considered palliative (PT), palliative definitive (PDT), and definitive (DT). RESULTS: The palliative treatment predominated. No statistically significant differences were observed in the patients undergoing PT, PDT, and DT, in regard to PPAAI, APCAI, and TNPAI. Comparing PPAAI and APCAI, no difference was observed for DT (P=0.4309); APCAI was greater than PPAAI for PT (P=0.0176); and APCAI was descriptively greater for PDT. The TNPAI of patients undergoing DT was greater than that of patients undergoing PT (P=0.0959). Five morphologically similar subgroups were identified and designated as B1, B2, B3, B4, and B5. Overall mortality was 17.5%. CONCLUSION: The morphometric characteristics are important, but the morphology of the pulmonary vascular blood supply of the PPAA and APCA proved to be better for guiding the surgical treatment. Independently of the didactical division into subgroups, PT predominated. Mortality was not correlated with the morphometric characteristics.

Transxiphoid approach without median sternotomy for the repair of atrial septal defects.

BACKGROUND Interest in minimally invasive procedures has recently increased because it results in less surgical trauma, decreased patient discomfort, short hospital stay, reduced costs, and better cosmetic appearance. Based on these facts, we have been using the transxiphoid process approach without sternotomy for the correction of atrial septal defects. METHODS From July 1996 to January 1997, the xiphoid process window approach was performed in 10 patients with ostium secundum atrial septal defect. Ages ranged from 6 months to 14 years (mean, 5.3 years). In all patients, extracorporeal circulation was carried out by means of cannulation of the femoral artery and both caval veins and of aortic cross-clamping. Videothoracoscopy was used to improve visualization of the aorta. RESULTS There were no intraoperative or postoperative complications, and in all but 1 patient, extubation was possible while in the operating room. CONCLUSIONS The xiphoid process window, with no median sternotomy, permitted closure of the atrial septal defects with good results and could be used as a less invasive technique for their correction.

Influence of Hypoxia on Nitric Oxide Synthase Activity and Gene Expression in Children With Congenital Heart Disease A Novel Pathophysiological Adaptive Mechanism

BackgroundChronic hypoxia has been shown to modulate nitric oxide (NO) responses in different cell models, but the relationship between hypoxia and NO synthase (NOS) regulation in humans was not studied. We studied the relationship between endothelial and inducible NOS (eNOS and iNOS) activities and expression and chronic hypoxia in children with cyanotic and acyanotic congenital heart defects. Methods and ResultsRight atrial tissue was excised from 18 patients during cardiac surgery. eNOS and iNOS activities were measured by conversion of l-[H3]arginine to l-[H3]citrulline. Gene expression of eNOS and iNOS was quantified by competitive reverse transcription–polymerase chain reaction. The eNOS activity and expression were significantly reduced in cyanotic hearts compared with acyanotic hearts: 0.38±0.14 versus 1.06±0.11 pmol · mg−1 · min−1 (P <0.0001) and 0.54±0.08 versus 0.80±0.10 relative optical density (ROD) of cDNA (P <0.0001), respectively. In contrast, iNOS activity and expression were significantly higher in cyanotic than in acyanotic children: 7.04±1.20 versus 4.17±1.10 pmol · mg−1 · min−1 (P <0.0001) and 2.55±0.11 versus 1.91±0.18 ROD of cDNA (P <0.0001), respectively. ConclusionsHypoxia downregulates eNOS activity and gene expression in cardiac tissue from patients with cyanotic congenital heart defects. By contrast, iNOS activity and expression are increased in cyanotic children and may represent an alternative mechanism to counteract the effects of hypoxia in the cardiovascular system. Therefore, a novel adaptive mechanism during hypoxia is suggested.

The improvement of care for paediatric and congenital cardiac disease across the World: a challenge for the World Society for Pediatric and Congenital Heart Surgery

The diagnosis and treatment for paediatric and congenital cardiac disease has undergone remarkable progress over the last 60 years. Unfortunately, this progress has been largely limited to the developed world. Yet every year approximately 90% of the more than 1,000,000 children who are born with congenital cardiac disease across the world receive either suboptimal care or are totally denied care.While in the developed world the focus has changed from an effort to decrease post-operative mortality to now improving quality of life and decreasing morbidity, which is the focus of this Supplement, the rest of the world still needs to develop basic access to congenital cardiac care. The World Society for Pediatric and Congenital Heart Surgery [http://www.wspchs.org/] was established in 2006. The Vision of the World Society is that every child born anywhere in the world with a congenital heart defect should have access to appropriate medical and surgical care. The Mission of the World Society is to promote the highest quality comprehensive care to all patients with pediatric and/or congenital heart disease, from the fetus to the adult, regardless of the patients economic means, with emphasis on excellence in education, research and community service.We present in this article an overview of the epidemiology of congenital cardiac disease, the current and future challenges to improve care in the developed and developing world, the impact of the globalization of cardiac surgery, and the role that the World Society should play. The World Society for Pediatric and Congenital Heart Surgery is in a unique position to influence and truly improve the global care of children and adults with congenital cardiac disease throughout the world [http://www.wspchs.org/].

Influence of the maze procedure on the treatment of rheumatic atrial fibrillation – evaluation of rhythm control and clinical outcome in a comparative study

OBJECTIVE The aim of this study was to evaluate the influence of the maze procedure on the treatment of rheumatic atrial fibrillation in patients with mitral valve disease. METHODS Fifty-five patients (mean age 51 years; 47 females) with rheumatic mitral valve disease and associated atrial fibrillation in New York Heart Association functional class III or IV, preoperatively, were operated upon. Thirty-five had double dysfunction, 19 had stenosis, and one had mitral regurgitation. None had other associated heart diseases or previous operations. The patients were divided into two groups: GI, 20 patients were treated for mitral valve disease with associated maze procedure; GII, 35 patients were treated for mitral valve disease without the maze procedure. The preoperative echocardiogram showed a left atrial diameter in GI of 5.35 mm and in GII of 5.57 mm (P=0.779). The groups were considered clinically similar (P=0.759). Cardiopulmonary bypass was used in all patients. The mitral valve was replaced with a biological prosthesis in 24 patients and repaired in 31 patients. RESULTS Three hospital deaths occurred, one in GI, two in GII. After cardiopulmonary bypass, 37.1% of patients in GII remained in atrial fibrillation. All patients in GI recovered regular rhythm (P<0.0001). In the ICU, atrial fibrillation was detected in 80% of patients in GII and maintained in 76.4% in a mean follow-up period of 38.5 months. In GI, atrial fibrillation occurred in 20% of patients in the ICU and maintained in 5.3% in 41 months of mean follow-up (P=0.0001). None of the patients in GI and 20.6% of patients in GII had a thromboembolic episode 1-63 months after the operation (P=0.041). Four late deaths occurred (two in each group), two being due to progression of valvular disease, one after an episode of pulmonary infection and one with no cardiac cause. CONCLUSION The maze procedure is effective in treating atrial fibrillation in patients with rheumatic mitral valve disease. The results are sustained in the mid-term follow-up period, preventing postoperative thromboembolic episodes, and with acceptable morbidity and mortality.

Hemostatic effects of fibrinogen concentrate compared with cryoprecipitate in children after cardiac surgery: A randomized pilot trial

OBJECTIVES Acute acquired hypofibrinogenemia in children undergoing cardiac surgery is a major concern because it often results in perioperative bleeding and high rates of allogeneic blood transfusion. Fibrinogen concentrate has been proposed as an alternative to cryoprecipitate (the gold standard therapy), with minimal infectious and immunologic risks. Our objective was to investigate the efficacy and safety of fibrinogen concentrate in children undergoing cardiac surgery. METHODS In this randomized pilot study, patients were allocated to receive fibrinogen concentrate (60 mg/kg) or cryoprecipitate (10 mL/kg) if bleeding was associated with fibrinogen levels<1 g/dL after cardiopulmonary bypass weaning. The primary outcome was postoperative blood losses during the 48 hours after surgery. RESULTS A total of 63 patients were included in the study, 30 in the fibrinogen concentrate group and 33 in the cryoprecipitate group. The median 48-hour blood loss was not significantly different between the 2 groups (320 mL [interquartile range, 157-750] vs 410 mL [interquartile range, 215-510], respectively; P=.672). After treatment, plasma fibrinogen concentration increased similarly following administration of both products. There were no differences in allogeneic blood transfusion after intervention treatment. CONCLUSIONS A large trial comparing fibrinogen concentrate and cryoprecipitate in the management of children with acute acquired hypofibrinogenemia during heart surgery is feasible. The preliminary results of our study showed that the use of fibrinogen concentrate was as efficient and safe as cryoprecipitate in the management of bleeding children undergoing cardiac surgery.

New transcatheter techniques for creation or enlargement of atrial septal defects in infants with complex congenital heart disease

To describe a series of 8 consecutive infants (5 with transposition of the great arteries [TGA] and 3 with hypoplastic left heart syndrome [HLHS]) who underwent nonconventional septostomy techniques.

Eight‐year experience of pediatric heart transplantation: Clinical outcome using non‐invasive methods for the evaluation of acute rejection

Abstract: Combined immunosuppression therapy and acute rejection surveillance after heart transplantation may influence clinical outcome. This prospective, longitudinal study investigated 27 pediatric patients (12 days to 12 yr of age; mean 3.0 yr) who underwent a post‐operative regimen that included long‐term treatment with cyclosporin A and azathioprine (double immunosuppression) and polyclonal anti‐thymocyte serum induction therapy. Non‐invasive parameters were used to diagnose acute rejection. The actuarial survival, clinical outcomes, and complications were analyzed. The actuarial survival after double immunosuppression and induction therapy with polyclonal anti‐thymocyte serum was 89%, 73%, and 57% at 1, 4, and 8 yr, respectively. The rejection frequency was 2.6 episodes/patient and the infection frequency, 3.7 episodes/patient. One year after transplantation, systemic arterial hypertension was detected in 21% of patients. Hence, double immunosuppression with polyclonal anti‐thymocyte serum induction therapy combined with surveillance of acute rejection with non‐invasive tests may provide promising clinical outcome in pediatric heart transplant recipients.

Fetal Heart Block: A New Experimental Model to Assess Fetal Pacing

Epicardial fetal pacing via thoracotomy has the potential of being a safer and more reliable procedure to treat congenital complete heart block (CHB) associated with fetal hydrops refractory to medical therapy. To assess the acute electrophysiological characteristics of two ventricular epicardial leads, a new experimental model of fetal heart block induced by cryosurgical ablation of the AV node without the need for fetal cardiac bypass was performed in 12 pregnant ewes at 110–115 days gestation. A modified screw‐in lead (1½ turns) was used in six fetal lambs and a stitch‐on lead in the other six lambs. CHB was achieved in 100% of the fetal lambs, with no ventricular escape rate noticed in any of the lambs. The acute stimulation thresholds were consistently low for both leads, with lower values for the screw‐in lead at pulse duration below 0.9 msec (P < 0.03). Current measured at voltage threshold with pulse width below 0.5 msec was lower for the screw‐in lead (P < 0.048). Stimulation resistance, measured during constant‐voltage pacing, was not statistically different between the two leads (441.8 ± 13.7 Ω for the screw‐in lead vs 480.2 ± 59.2 Ω for the stitch‐on lead). No significant differences (P > 0.20) were found in R wave amplitude between the two electrodes. Slew rates were significantly higher in the screw‐in group than in the stitch‐on group (1.40 ± 0.2 vs 0.62 ± 0.2 V/sec, P = 0.04). This model of CHB is a simple and reproducible method to assess fetal pacing. We find the screw‐in electrode to be a better option when fetal pacing is indicated.

Perventricular device closure of congenital muscular ventricular septal defects

Muscular ventricular septal defects (MVSDs) account for approximately 20% of all congenital ventricular septal defects. Large defects in infants result in early heart failure, failure to thrive and pulmonary hypertension. Although percutaneous closure of MVSDs has been employed safely and effectively in children, adolescents and adults, its application in the small infant (weight <6 kg) carries a higher risk for complications including arrhythmias, hemodynamic compromise, cardiac perforation, tamponade and death. Perventricular closure of such defects, introduced by Amin and coworkers in the late 1990s, has become an attractive treatment modality for these small and high-risk patients. Experience worldwide has shown that the procedure is feasible, reproducible, safe and effective. In this article, the authors review the indications, the step-by-step technique and the results of perventricular closure of MVSDs using the AMPLATZER® mVSD device (AGA Medical, MN, USA).