Rui Anjos

Determinants of hemodynamic results of balloon dilation of aortic recoarctation

Between October 1982 and May 1990, balloon dilation of aortic recoarctation was attempted in 27 patients. In 1 case dilation was not performed owing to suspected aortic perforation. The remaining 26 patients had 30 procedures. The age at the first dilation ranged between 2.6 months and 18.3 years. After dilation, systolic gradient decreased from 49 +/- 17 mm Hg to 20 +/- 17 mm Hg (p less than 0.001). A reduction of gradient to less than or equal to 20 mm Hg occurred after the first dilation in 17 of 26 (65%) patients. Residual gradients between 25 and 80 mm Hg were present in the remaining 9 patients. During follow-up of 2 months to 6.7 years, 5 of 17 patients with a good initial result developed further recoarctation (2 had successful redilation, 2 had reoperation, and 1 is awaiting repeat dilation). Of 9 patients with gradients greater than 20 mm Hg after the first dilation, 1 had successful redilation and 3 had reoperation. The remaining 5 patients are being managed conservatively. 2 patients developed aneurysms after dilation (1 immediately and the other at 2 months). In all, 15 patients (58%) had a good, and 11 (42%) a poor late hemodynamic result. Aortic diameters at different levels of the aortic arch and at the reconstructed isthmus (normalized to the aorta at the level of the diaphragm) were significantly higher in the group with a good late result than in that with a poor one. Balloon/aortic diameter ratio at diaphragm level also had a significant influence on the late results.

Aortic Coarctation Repair in the Adult

Aortic coarctation can be repaired surgically or percutaneously. The decision should be made according to the anatomy and location of the coarctation, age of the patient, presence of other cardiac lesions, and other anatomic determinants (extensive collaterals or aortic calcification). This article reviews the different therapeutic options available, explaining the differences between children and adults, describing different approaches to the same disease, exemplified by three cases of nonclassic surgical approach and one percutaneous treatment. doi: 10.1111/jocs.12367 (J Card Surg 2014;29:512–518)

Use of Peritoneal Dialysis After Surgery for Congenital Heart Disease in Children

Acute kidney injury (AKI) is a common complication in children after surgery for congenital heart disease, and peritoneal dialysis (PD) is usually the renal replacement therapy (RRT) of choice, especially in very young children. The aim of the present study was to describe our experience of using PD to treat AKI after cardiac surgery. We retrospectively analyzed children 1 week to 16 years of age undergoing cardiac surgery during 2000 – 2008 and found the incidence of AKI treated with PD to be 2.3%. In the 23 patients treated with PD (13 male; average age: 29 ± 48.4 months; weight: 9.1 ± 8.1 kg), the indications for PD initiation were oliguria (n = 13), anuria (n = 9), and acidosis (n = 1). The average time between cardiac surgery and AKI was 4.8 ± 16.8 hours, and between AKI and PD initiation, it was 12 ± 16.8 hours. Patients were treated for a mean of 4.8 ± 3.8 days. Two patients developed peritonitis, and mechanical dysfunction of the PD catheter occurred in 1 patient. In-hospital mortality was 43.4%. Patients treated with PD weighed less (p = 0.004) and had longer bypass time (p = 0.004), inotrope use (p = 0.000), and mechanical ventilation (p = 0.000). However, in a regression analysis, only cardiopulmonary bypass time (odds ratio: 1.021; 95% confidence interval: 0.998 to 1.027; p = 0.032) remained predictive of a subsequent need for PD. We conclude that PD is an efficacious RRT for AKI in children undergoing cardiac surgery and that, in this setting, bypass time is the strongest predictor of a subsequent need for RRT.

Evaluation of pulmonary artery anatomy using magnetic resonance: The importance of multiplanar and oblique imaging

SummaryPulmonary artery anatomy was studied in 36 patients (age range 12 days to 12.83 years, mean 2.9 years) with right ventricular outflow tract obstruction over a 3-year period using a 1.5 Tesla Magnetic Resonance system. Gated spin-echo sequences were obtained in each patient. Image planes used were straight and oblique transverse, oblique coronal, and oblique sagittal. The studies were analyzed retrospectively and comparative angiographic, surgical, and postmortem data was available in all cases. As previously noted with other imaging modalities, multiple views and oblique cuts were found to increase significantly the quality and accuracy of the information acquired. In 12 of the 15 patients who had axial and coronal imaging of both branch pulmonary arteries, the pulmonary arteries were unequivocally demonstrated to at least the first hilar branch. However, early in our experience we missed a number of branch stenoses that developed following surgical anastomoses. These mistakes were caused by inadequate or inappropriate slice acquisition. Magnetic resonance is an important technique for imaging pulmonary arteries. Careful use of the appropriate imaging planes is essential for accurate demonstration of the anatomy.

Screening of copy number variants in the 22q11.2 region of congenital heart disease patients from the São Miguel Island, Azores, revealed the second patient with a triplication

BackgroundThe rearrangements in the 22q11.2 chromosomal region, responsible for the 22q11.2 deletion and microduplication syndromes, are frequently associated with congenital heart disease (CHD). The present work aimed to identify the genetic basis of CHD in 87 patients from the São Miguel Island, Azores, through the detection of copy number variants (CNVs) in the 22q11.2 region. These structural variants were searched using multiplex ligation-dependent probe amplification (MLPA). In patients with CNVs, we additionally performed fluorescent in situ hybridization (FISH) for the assessment of the exact number of 22q11.2 copies among each chromosome, and array comparative genomic hybridization (array-CGH) for the determination of the exact length of CNVs.ResultsWe found that four patients (4.6%; A to D) carried CNVs. Patients A and D, both affected with a ventricular septal defect, carried a de novo 2.5 Mb deletion of the 22q11.2 region, which was probably originated by inter-chromosomal (inter-chromatid) non-allelic homologous recombination (NAHR) events in the regions containing low-copy repeats (LCRs). Patient C, with an atrial septal defect, carried a de novo 2.5 Mb duplication of 22q11.2 region, which could have been probably generated during gametogenesis by NAHR or by unequal crossing-over; additionally, this patient presented a benign 288 Kb duplication, which included the TOP3B gene inherited from her healthy mother. Finally, patient B showed a 3 Mb triplication associated with dysmorphic facial features, cognitive deficit and heart defects, a clinical feature not reported in the only case described so far in the literature. The evaluation of patient B’s parents revealed a 2.5 Mb duplication in her father, suggesting a paternal inheritance with an extra copy.ConclusionsThis report allowed the identification of rare deletion and microduplication syndromes in Azorean CHD patients. Moreover, we report the second patient with a 22q11.2 triplication, and we suggest that patients with triplications of chromosome 22q11.2, although they share some characteristic features with the deletion and microduplication syndromes, present a more severe phenotype probably due to the major dosage of implicated genes.

Percutaneous closure of atrial right-to-left shunt in patients with Ebstein's anomaly of the tricuspid valve

AIMS Patients with Ebsteins anomaly of the tricuspid valve may have right-to-left shunt at atrial level resulting in hypoxaemia, high haematocrit and hyperviscosity syndrome. The purpose of this study was to assess the results of percutaneous closure of atrial right-to-left shunt in patients with Ebsteins anomaly. METHODS AND RESULTS Records of patients treated between January 2002 and June 2010 were reviewed. Their condition before and after shunt closure (clinical data, oxygen saturation and haematocrit) were studied. During this period nine selected patients with Ebsteins anomaly and right-to-left shunt at atrial level were treated. Ages ranged from six to 67 years; seven were male. Mean pulmonary artery pressures were under 25 mmHg in all. Three patients had previous episodes of stroke and three had very high haematocrit, two of whom required therapeutic phlebotomies. Test occlusion of the shunt was performed in all patients with a balloon catheter, revealing an increase in systemic oxygen saturation, with right atrial pressures remaining <18 mmHg in all. Percutaneous closure of atrial shunt was achieved in all. There were no major complications. Arterial oxygen saturations increased in all patients from 85.0 ± 4.5% to 96.7 ± 1.5% (mean ± standard deviation). Medium follow-up was five years. The three patients with very high haematocrit levels had a decrease in its values from 62.9 ± 2.8% to 45.5 ± 3.9% after device occlusion. Both therapeutic phlebotomy programs were discontinued. All patients reported a marked improvement in effort tolerance. CONCLUSIONS Percutaneous closure of atrial right-to-left shunt in selected patients with Ebsteins anomaly offers significant improvement, abolishing hypoxaemia and hyperviscosity and preventing paradoxical embolisation.

Balloon dilatation of a stenosed aortic homograft conduit following repair of the common arterial trunk

SummaryAn 8-year-old boy, who underwent surgical correction of a common arterial trunk at the age of 10 months, developed stenosis of the 15-mm aortic homograft. Chest x-ray demonstrated calcification of the homograft, and at cardiac catheterization there was a 57 mmHg gradient across the conduit. He underwent balloon dilatation using a 15-mm balloon catheter. After four inflations at a pressure of 5.5 atm, the gradient decreased to 34 mmHg. Six months later he had a Doppler-estimated gradient of 38 mmHg.

Absence of one atrioventricular connexion — a terminologic problem

We present a patient in whom the heart was right-sided, with usual atrial position, absence of the right-sided atrioventricular connexion, and a single outlet via the aorta from a dominant morphologically right ventricle. We use the case to illustrate potential problems in the terminology as used to describe the absence of one atrioventricular connexion. Our case shows why absence of one atrioventricular connexion must be classified according to the side of the missing connexion, and not the anatomy of the atrial or ventricular chambers involved. To simplify the approach to certain hearts, the use of the concept of one concordant or discordant atrioventricular connexion may be justified when the other atrioventricular connexion is absent.

IL-7-Induced Proliferation of Human Naive CD4 T-Cells Relies on Continued Thymic Activity

Naive CD4 T-cell maintenance is critical for immune competence. We investigated here the fine-tuning of homeostatic mechanisms of the naive compartment to counteract the loss of de novo CD4 T-cell generation. Adults thymectomized in early childhood during corrective cardiac surgery were grouped based on presence or absence of thymopoiesis and compared with age-matched controls. We found that the preservation of the CD31− subset was independent of the thymus and that its size is tightly controlled by peripheral mechanisms, including prolonged cell survival as attested by Bcl-2 levels. Conversely, a significant contraction of the CD31+ naive subset was observed in the absence of thymic activity. This was associated with impaired responses of purified naive CD4 T-cells to IL-7, namely, in vitro proliferation and upregulation of CD31 expression, which likely potentiated the decline in recent thymic emigrants. Additionally, we found no apparent constraint in the differentiation of naive cells into the memory compartment in individuals completely lacking thymic activity despite upregulation of DUSP6, a phosphatase associated with increased TCR threshold. Of note, thymectomized individuals featuring some degree of thymopoiesis were able to preserve the size and diversity of the naive CD4 compartment, further arguing against complete thymectomy in infancy. Overall, our data suggest that robust peripheral mechanisms ensure the homeostasis of CD31− naive CD4 pool and point to the requirement of continuous thymic activity to the maintenance of IL-7-driven homeostatic proliferation of CD31+ naive CD4 T-cells, which is essential to secure T-cell diversity throughout life.

Doppler evaluation of superior caval venous pathways after Mustard and Senning operations

Doppler waveforms from the superior caval vein were analysed to evaluate the patency of superior caval venous pathways following venous redirection (Mustard and Senning) operations for complete transposition. The group consisted of 26 unselected survivors of Mustard (9 patients) and Senning operations (17 patients). Patients were examined a mean of 5.9 (range 0.1-15.3) years following operation and their age at study ranged from 0.4-25.3 years, mean 7.3 years. Doppler waveforms were correlated with digital subtraction angiograms, which were performed in every patient within 24 hours of the Doppler study. Totally occluded superior caval venous pathways were identified in 3 patients with digital subtraction angiography. The remaining patients had angiographically patent pathways. In the 23 patients with patent pathways, Doppler waveforms demonstrated an initial systolic peak smaller than a second diastolic peak. In the 3 patients with totally occluded pathways, the pattern of the waveform was reversed, with the systolic larger than the diastolic peak. Doppler examination of the superior caval vein is a quick and simple bedside method of accurately determining patency of superior caval venous pathways after atrial redirection procedures for complete transposition.