Incidence, risk factors and outcomes of atrial arrhythmias in adult patients with atrioventricular septal defect

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): French Federation of Cardiology

Background

The number of adults with atrioventricular septal defects (AVSD) is growing, with however, very few data regarding the natural history of atrial arrhythmias in this specific population. We aimed to assess the incidence, associated factors and outcomes of atrial arrhythmias among adult patients with AVSD.

Methods

Multicentric retrospective cohort of patients with AVSD from 3 referral centers specialized in adult congenital heart disease. Unbalanced AVSD, univentricular hearts, and Eisenmenger syndromes were excluded. Lifetime cumulative incidences of different types of atrial arrhythmia (>30 seconds) were analyzed (atrial fibrillation [AF] and intra atrial reentrant tachycardia/focal atrial tachycardia [IART/FAT]). Multiple logistic regression models were used to identify risk factors for atrial arrhythmias.

Results

The cohort comprised of 391 patients (61.6% of women) with a mean age of 36.3 ± 16.3 years and 17.3 ± 14.2 years of follow-up after surgical repair in operated patients, including 333 (85.1%) partial/intermediate and 58 (1.0%) complete AVSD. Overall, atrial arrhythmias were documented in 98 patients (25.1%).

The lifetime risks for developing atrial arrhythmia to ages 20, 40, and 60 were 3.7%, 17.6%, and 54.8%. IART/FAT was the leading arrhythmia until the age of 45 then AF surpassed IART/FAT.

Age (OR = 1.4, 95%CI = 1.2-1.6 by 5 years increment), the number of cardiac surgeries (OR = 4.1, 95%CI = 2.5-6.9), left atrial dilatation (OR = 3.1, 95%CI = 1.4-6.8), right atrial dilatation (OR = 4.1, 95%CI = 1.7-10.3), and moderate or severe left AV valve regurgitation (OR = 3.7, 95%CI = 1.2-11.7) were independently associated with a higher risk of atrial arrhythmias. Patients with atrial arrhythmias more frequently had pacemaker implantation (41.8% vs. 8.5%, p < 0.001), heart failure (24.5% vs 1.0%, p < 0.001) and cerebrovascular accidents (11.2% vs 3.4%, p = 0.007).

Conclusions

The lifetime risk of atrial arrhythmias in patients with AVSD is considerable with more than half of patients who will develop an atrial arrhythmia by the age of 60. Atrial arrhythmias are associated with a significant morbidity in this population. Abstract Figure. Central Illustration AVSD

Long-term outcomes amongst adults with anatomic repair for transposition of the great arteries: not as perfect as we would have hoped?

Background

The arterial switch operation (ASO) has replaced atrial switch procedures for D-transposition of the great arteries (D-TGA), with 90% of patients now reaching adulthood. However, patients may have residual lesions and/or sequelae, some of which may remain unrecognized, necessitating lifelong specialist surveillance. We examined the cardiac outcomes of a large number of contemporary ASO patients under tertiary adult congenital heart disease (ACHD) care.

Methods

We examined late major adverse cardiovascular events (MACE) in adult TGA patients (>16 years) who underwent an ASO between 1981 and 2003 and continued their follow-up in 2 tertiary ACHD centers. MACE were defined as death, re-intervention, myocardial ischemia, arrhythmia, stroke/TIA, infective endocarditis and heart failure.

Results

Overall, 199 patients (66% male, mean age 27±5 years) were followed in adult life for a median of 10 years [IQR 7–15] and were included in this study. Overall survival during this period was 99.5% (95% confidence interval [CI]: 94.4%-99.8%). Sixty-two (31.2%) patients experience MACE, including 52 reinterventions. MACE and reintervention-free survival at 20, 30 and 35 years were 87.6%, 58.6%, 50.6% and 89.5%, 69.1, 61%, respectively. Atrial arrhythmia was the most frequent cardiac event with an incidence of 5.5 cases per 1000 patient-years, whereas incidence of ventricular tachycardia and sudden cardiac death was 1.8‰ and 0.9‰ patient-years, respectively. Coronary artery disease was diagnosed in 6 (3%) patients, of whom 4 had symptoms, 1 had ST depression on ECG at rest and 3 had abnormal wall motion on echocardiography. The most frequent indication for reoperation was right ventricular outflow tract obstruction (n=35/52, 63.7%), whereas left ventricular outflow tract (LVOT) re-interventions rate increased significantly during adulthood compared to childhood from 1% to 5%, p=0.03 (Figure 1). On multivariate analysis, history of cardiac complications during infancy (HR 2.3, 95% CI:1.3–4.0, p<0.01) and uncommon coronary patterns (HR for type A versus B/C/D/E 0.47, 95% CI:0.26–0.83, p<0.01) were independent predictors of MACE in adulthood. At the latest follow-up, 90.9% of patients were functional class I, left ventricular ejection fraction was 59.6±6.5% and peak oxygen uptake 71.1±24.9% predicted. At least moderate neoaortic regurgitation and aortic dilatation (≥40mm) were present in 8.0% and 35.2%, respectively, with more than mild pulmonary stenosis in 19.6%.

Conclusion

Adult patients with ASO for TGA have a low late mortality. However, MACE are common requiring reintervention, particularly for RVOT obstruction and neo-aortic valve dysfunction, the latter with rising rates during adulthood. Patients with cardiovascular complications during childhood are at the highest risk for MACE. All patients merit life-long tertiary care.

Figure 1

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Assistance Publique des Hôpitaux de Paris

Catheter ablation in adults with congenital heart disease: a 15-year perspective from a tertiary center

Background

With the growing population of adults with congenital heart disease (ACHD), the number of catheter ablation procedures is expected to increase over time.

Purpose

We aimed to describe temporal trends in volume and outcomes of catheter ablation procedures in ACHD patients in a large tertiary center.

Methods

Retrospective observational study including all consecutive ACHD patients undergoing catheter ablation in a tertiary reference center over a 15-year period. Acute procedural success rate (including complete success in case of non-inducibility of any arrhythmia at the end of the procedure) as well as freedom from recurrence at 12 months were analyzed.

Results

From November 2004 to November 2019, 302 catheter ablations in 221 ACHD patients (43.6±15.0 years, 58.9% males) were performed. The annual number of catheter ablation increased progressively from 4 to 60 by year (p<0.001). Intra-atrial reentrant tachycardia/focal atrial tachycardia was the most common targeted arrhythmia (n=217, 71.9%). Over the study period, acute procedural success rate increased from 45.0% to 93.3% (p<0.001), including complete acute procedural success from 45.0% to 88.1% (p<0.001) (Figure 1). The use of irrigated catheters (30.0% to 94.8%, p<0.001), 3D-mapping systems (60.0% to 96.3%, p<0.001), contact force catheters (0.0% to 91.9%, <0.001), and high-density mapping (0.0% to 71.9%, p<0.01) increased significantly. Use of irrigated catheters (OR=3.96, 95% CI: 1.79–8.55), 3D-mapping system (OR=3.55, 95% CI: 1.62–7.55), contact force catheters (OR=3.46, 95% CI: 1.71–7.25), and high-density mapping (OR=3.85, 95% CI: 1.60–7.26) were associated with acute procedural success. The rate of freedom from any recurrence at 12 months increased from 29.4% to 66.2% (p=0.001). Seven (2.3%) non-fatal complications occurred.

Conclusions

The number of catheter ablation procedures in ACHD patients has considerably increased over the last 15 years. Advances in ablative technologies appear to be associated with a low rate of complications and a significant improvement in acute and midterm outcomes.

Evolution of acute procedural success

Funding Acknowledgement

Type of funding source: None

Passage of uranium through human cerebral microvascular endothelial cells: influence of time exposure in mono- and co-culture in vitro models

PURPOSE

Depleted uranium (DU) has several civilian and military applications. The effects of this emerging environmental pollutant on human health raise some concerns. Previous experimental studies have shown that uranium (U) exposure can disturb the central nervous system. A small quantity of U reaches the brain via the blood, but the effects on the blood-brain barrier (BBB) remain unclear.

MATERIALS AND METHODS

In the present work, two cell culture models were exposed to DU for different times to study its cytotoxicity, paracellular permeability and extracellular concentration of U. The well-known immortalized human cerebral microvascular endothelial cells, hCMEC/D3, were cultured on the filter in the first model. In the second model, human primary cells of pericytes were cultured under the filter to understand the influence of cell environment after U exposure.

RESULTS

The results show that U is not cytotoxic to hCMEC/D3 cells or pericytes until 500 µM (1.6 Bq.L^-1). In addition, acute or chronic low-dose exposure of U did not disturb permeability and was conserved in both cell culture models. However, U is able to reach the brain compartment. During the first hours of exposure, the passage of U to the abluminal compartment was significantly reduced in the presence of pericytes. Electronic microscopy studies evidenced the formation of needlelike structures, like urchin-shaped precipitates, from 1 h of exposure. Analytical microscopy confirmed the U composition of these precipitates. Interestingly, precipitated U was detected only in endothelial cells and not in pericytes. U was localized in multilamellar or multivesicular bodies along the endo-lysosomal pathway, suggesting the involvement of these traffic vesicles in U sequestration and/or elimination.

CONCLUSIONS

We show for the first time the in vitro passage of U across a human cerebral microvascular endothelial cells, and the intracellular localization of U precipitates without any cytotoxicity or modification of paracellular permeability. The difference between the results obtained with monolayers and co-culture models with pericytes illustrates the need to use complex in vitro models in order to mimic the neurovascular unit. Further in vivo studies should be performed to better understand the passage of U across the blood-brain barrier potentially involved in behavioral consequences.

P4165Influence of restrictive right ventricular physiology in outcomes after transcatheter pulmonary valve implantation in adult patients

Background

A restrictive right ventricular (RV) physiology (r-RVP) is present in almost half of the patients with repaired tetralogy of Fallot (ToF), but its effect on later patients' clinical status is controversial.

Purpose

Evaluate the outcomes after transcatheter pulmonary valve implantation (TPVI) in patients with restrictive versus non-restrictive RV.

Methods

Single-center retrospective study of patients who underwent TPVI for pulmonary regurgitation between 2008 and 2017. Electrocardiogram, transthoracic echocardiogram, cardiac magnetic resonance and cardio-pulmonary exercise test were performed previous to TPVI and repeated 12 months after. For statistical analysis restrictive physiology was defined as the presence of end-diastolic forward flow (EDFF) and RVEDVi <150ml/m2.

Results

Fifty-nine patients, 55 with tetralogy of Fallot, were included. R-RVP was present in 23 patients (39.0%). At the baseline, the majority of the patients were symptomatic, in NYHA functional class II–III (n=48, 81.4%) and with reduced cardiopulmonary performance (VO2max = 20.5mL/min/kg), both worse among patients with r-RVP (p=0.018 and p=0.018). During a mean follow-up of 446.4±226.1 days after TPVI one patient died. BNP levels were not significantly different from baseline. Despite self-reported functional capacity and exercise capacity improvement after TPVI (p<0.001), all parameters remained lower in r-RVP group. One year after TPVI, pulmonary and tricuspid regurgitation decrease significantly, as well as RVEDV, in both groups. However, RV systolic function remained unchanged in both groups. Regarding to the dysrhythmic profile, all patients with need for an implantable cardiac defibrillator and seven of the eight patients requiring radiofrequency ablation for sustained supraventricular arrhythmias during follow-up were in the group without r-RVP (p=0.038).

Kaplan-Meier survival curve

Conclusion

TPVI had a positive impact in clinical status in a cohort of patients with predominant PR regardless the presence of restrictive physiology. Moreover, besides higher VO2max and anaerobic threshold in the non-restrictive group, the magnitude of the improvement was not statistically different between the two groups. Nevertheless, in patients without r-RVP, a peculiar caution has to be focused regarding rhythmic issue during follow-up, despite the TPVI.

[Cardiac rehabilitation in adults with congenital heart diseases]

The great advances in the medical and surgical management of congenital heart diseases have allowed many children to reach adulthood with often a good hemodynamic result. Nevertheless most of these adults have a limitation of their functional capacity. This limitation is more or less important, penalizes them in their daily life and alters their quality of life. The origin of this limitation is generally multifactorial. It is linked, of course, to the severity of the heart disease and the quality of the operative result. But there is very often a physical deconditioning. It can be secondary to the heart disease but is often secondary to a lack of physical activity. It is the parents, sometimes overprotective, but frequently the doctors who imposed, often wrongly, this restriction. It is essential to take this dimension into account in view of the important benefits expected for health and quality of life. Cardiac rehabilitation is a privileged tool for providing advice in a suitable environment. This requires close collaboration between cardiac rehabilitators and congenital cardiologists to offer appropriate care. We bring here some reflections and the basic elements to guide the re-training of these patients.

Cut-off values for normal sperm morphology and toxicology for automated analysis of rat sperm morphology and morphometry

We used automated sperm morphology analysis to investigate rat sperm morphometry and morphology in Sprague-Dawley and Wistar rats in three research centers to develop normal baseline values for sperm morphometry and to quantify the percentage of morphologically normal sperm in healthy rats. The participating centers were IRSN in Paris, France (Sprague-Dawley rats), University of the Western Cape, South Africa (Wistar rats) and Stellenbosch University (Wistar rats), South Africa. All three centers used identical sperm isolation techniques from the cauda epididymis, the same staining protocols, identical computer-aided sperm morphometry analysis (CASMA) software and microscopes with similar optics. With CASMA, fully automated analysis of the different parts of stained sperm, e.g., head, acrosome, mid-piece, can be performed, many sperm morphometric features can be measured accurately and eventually normal sperm morphology can be defined. We found that it is possible to distinguish sperm morphometric characteristics of Sprague-Dawley and Wistar rats. We also developed cut-off values for evaluating the percentage normal sperm in these two rat strains using the automatic analysis mode. Normal sperm morphology varied between 67 and 74% by contrast with previous findings of > 90%.

DNA methylation and potential multigenerational epigenetic effects linked to uranium chronic low-dose exposure in gonads of males and females rats

INTRODUCTION

An increased health problem in industrialised countries is the contemporary concern of public and scientific community as well. This has been attributed in part to accumulated environmental pollutants especially radioactive substances and the use of nuclear power plants worldwide. However, the outcome of chronic exposure to low doses of a radionuclide such as uranium remains unknown. Recently, a paradigm shift in the perception of risk of radiotoxicology has emerged through investigating the possibility of transmission of biological effects over generations, in particular by epigenetic pathways. These processes are known for their crucial roles associated with the development of several diseases.

OBJECTIVE

The current work investigates the epigenetic effect of chronic exposure to low doses of uranium and its inheritance across generations. Materials and Methods To test this proposition, a rodent multigenerational model, males and females, were exposed to a non-toxic concentration of uranium (40mgL^-1 drinking water) for nine months. The uranium effects on were evaluated over three generations (F0, F1 and F2) by analysing the DNA methylation profile and DNMT genes expression in ovaries and testes tissues.

RESULTS

Here we report a significant hypermethylation of testes DNA (p <0.005) whereas ovaries showed hypomethylated DNA (p <0.005). Interestingly, this DNA methylation profile was significantly maintained across generations F0, F1 and F2. Furthermore, qPCR results of both tissues imply a significant change in the expression of DNA methyltransferase genes (DNMT 1 and DNMT3a/b) as well.

CONCLUSION

Altogether, our work demonstrates for the first time a sex-dependance and inheritance of epigenetic marks, DNA methylation, as a biological response to the exposure to low doses of uranium. However, it is not clear which type of reproductive cell type is more responsive in this context.

Identification of four novel genes contributing to familial elevated plasma HDL cholesterol in humans

While genetic determinants strongly influence HDL cholesterol (HDLc) levels, most genetic causes underlying variation in HDLc remain unknown. We aimed to identify novel rare mutations with large effects in candidate genes contributing to extreme HDLc in humans, utilizing family-based Mendelian genetics. We performed next-generation sequencing of 456 candidate HDLc-regulating genes in 200 unrelated probands with extremely low (≤10th percentile) or high (≥90th percentile) HDLc. Probands were excluded if known mutations existed in the established HDLc-regulating genes ABCA1, APOA1, LCAT, cholesteryl ester transfer protein (CETP), endothelial lipase (LIPG), and UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 2 (GALNT2). We identified 93 novel coding or splice-site variants in 72 candidate genes. Each variant was genotyped in the proband's family. Family-based association analyses were performed for variants with sufficient power to detect significance at P < 0.05 with a total of 627 family members being assessed. Mutations in the genes glucokinase regulatory protein (GCKR), RNase L (RNASEL), leukocyte immunoglobulin-like receptor 3 (LILRA3), and dynein axonemal heavy chain 10 (DNAH10) segregated with elevated HDLc levels in families, while no mutations associated with low HDLc. Taken together, we have identified mutations in four novel genes that may play a role in regulating HDLc levels in humans.

Segregation of LIPG, CETP, and GALNT2 mutations in Caucasian families with extremely high HDL cholesterol

To date, few mutations are described to underlie highly-elevated HDLc levels in families. Here we sequenced the coding regions and adjacent sequence of the LIPG, CETP, and GALNT2 genes in 171 unrelated Dutch Caucasian probands with HDLc≥90th percentile and analyzed segregation of mutations with lipid phenotypes in family members. In these probands, mutations were most frequent in LIPG (12.9%) followed by GALNT2 (2.3%) and CETP (0.6%). A total of 6 of 10 mutations in these three genes were novel (60.0%), and mutations segregated with elevated HDLc in families. Interestingly, the LIPG mutations N396S and R476W, which usually result in elevated HDLc, were unexpectedly found in 6 probands with low HDLc (i.e., ≤10th percentile). However, 5 of these probands also carried mutations in ABCA1, LCAT, or LPL. Finally, no CETP and GALNT2 mutations were found in 136 unrelated probands with low HDLc. Taken together, we show that rare coding and splicing mutations in LIPG, CETP, and GALNT2 are enriched in persons with hyperalphalipoproteinemia and segregate with elevated HDLc in families. Moreover, LIPG mutations do not overcome low HDLc in individuals with ABCA1 and possibly LCAT and LPL mutations, indicating that LIPG affects HDLc levels downstream of these proteins.

Novel mutations in scavenger receptor BI associated with high HDL cholesterol in humans

The scavenger receptor class B, member 1 (SR-BI), is a key cellular receptor for high-density lipoprotein (HDL) in mice, but its relevance to human physiology has not been well established. Recently a family was reported with a mutation in the gene encoding SR-BI and high HDL cholesterol (HDL-C). Here we report two additional individuals with extremely high HDL-C (greater than the 90th percentile for age and gender) with rare mutations in the gene encoding SR-BI. These mutations segregate with high HDL-C in family members of each proband and are associated with a 37% increase in plasma HDL-C in heterozygous individuals carrying them. Both mutations occur at highly conserved positions in the large extracellular loop region of SR-BI and are predicted to impair the function of the SR-BI protein. Our findings, combined with the prior report of a single mutation in the gene encoding SR-BI, further validate that mutations in SR-BI are a rare but recurring cause of elevated HDL-C in humans.

Increased risk of coronary artery disease in Caucasians with extremely low HDL cholesterol due to mutations in ABCA1, APOA1, and LCAT

Mutations in ABCA1, APOA1, and LCAT reduce HDL cholesterol (HDLc) in humans. However, the prevalence of these mutations and their relative effects on HDLc reduction and risk of coronary artery disease (CAD) are less clear. Here we searched for ABCA1, APOA1, and LCAT mutations in 178 unrelated probands with HDLc <10th percentile but no other major lipid abnormalities, including 89 with ≥1 first-degree relative with low HDLc (familial probands) and 89 where familial status of low HDLc is uncertain (unknown probands). Mutations were most frequent in LCAT (15.7%), followed by ABCA1 (9.0%) and APOA1 (4.5%), and were found in 42.7% of familial but only 14.6% of unknown probands (p=2.44∗10(-5)). Interestingly, only 16 of 24 (66.7%) mutations assessed in families conferred an average HDLc <10th percentile. Furthermore, only mutation carriers with HDLc <5th percentile had elevated risk of CAD (odds ratio (OR)=2.26 for 34 ABCA1 mutation carriers vs. 149 total first-degree relative controls, p=0.05; OR=2.50 for 26 APOA1 mutation carriers, p=0.04; OR=3.44 for 38 LCAT mutation carriers, p=1.1∗10(-3)). These observations show that mutations in ABCA1, APOA1, and LCAT are sufficient to explain >40% of familial hypoalphalipoproteinemia in this cohort. Moreover, individuals with mutations and large reductions in HDLc have increased risk of CAD. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).

[Genetic aspects of valvulopathies]

Valvular dystrophies due to myxoid degeneration are common and potentially serious cardiac pathologies. They constitute a heterogeneous group of which the most usual is idiopathic mitral valvular prolapse (Barlow's disease). The majority of mitral valvular prolapses are sporadic, but there are several familial forms. Transmission is usually autosomal dominant with incomplete penetrance and variable expression. The first chromosomal location to be identified was on the 16p11-13 chromosome. Since then, two other loci have been identified on the 11p15.4 and 13q31-32 chromosomes. Our team has recently identified the first gene responsible for myxoid valvulopathy linked to the X chromosome, from a large family of 318 members. This is the gene that codes for filamin A, which is a cytoskeleton protein. The frequency of mutations in this gene is still unknown, but out of 7 families in which transmission was compatible with X-linked transmission, mutations were discovered in 4 of the families. Thanks to a genetic epidemiological approach, we have also demonstrated that there are familial forms of aortic stenosis, which are probably common. Identification of the genes implicated in these common forms of valvular pathology is important, as it will allow a better understanding of the pathophysiology of these valvular disorders and could lead to better therapeutic management in the future.

[The role of aortic morphology in the occurrence of hypertension in patients undergoing surgery for coarctation of the aorta before the age of 1 year]

OBJECTIVE

Hypertension on effort can be observed following surgical treatment of coarctation of the aorta even if the operation has been performed early and has been judged to be satisfactory. The pathophysiology of this hypertension has not been completely elucidated. The aim of our study was to look for a residual morphological anomaly of the aortic arch which might be responsible.

METHODS

This was a retrospective study of patients aged over 10 years who had undergone surgery for coarctation of the aorta before the age of 1 year, consecutively between 1979 and 1993, and free from re-coarctation clinically or with Doppler. All of them had a blood pressure effort test on a cycling machine, echocardiography and an MRI of the thoracic aorta.

RESULTS

61 patients were included. Their median age was 15 years, 59% were male, 15% were hypertensive at rest and 56% on effort. With univariate analysis, only the average blood pressure (p=0.03) and the resting pulse pressure (p=0.001) were associated with hypertension on effort. With multivariate analysis the only factors that correlated independently with maximum arterial pressure on effort were the height of the patient (p=0.02) and the pulse pressure (p<0.0001). The surgical technique and the age at intervention were not associated with hypertension on effort (p=0.96 and 0.69 respectively). The diameter of the horizontal aorta and the aorta at the site of repair, measured on MRI, added to the diameter of the descending aorta at the diaphragm were not lower in patients with hypertension on effort (p=0.77 and 0.38). There were proportionally more Roman type aortic arches than Gothic types in patients with hypertension on effort, but this difference was not significant (p=0.18).

CONCLUSION

In our study, the patients with hypertension on effort following correction of coarctation of the aorta did not display any residual obstruction at the level of the aortic cross on MRI. However, they had a resting pulse pressure that was significantly higher than the non hypertensive patients, reflecting an increase in the aortic wall rigidity.

[Quality of life of patients with total cavopulmonary anastomosis]

INTRODUCTION

Total cavo-pulmonary connection (TCPC) represents the current surgery standard for congenital univentricular heart disease (CUHD) patients. We studied the health related quality of life (HRQOL) expressed by TCPC operated patients.

PATIENTS AND METHODS

This transversal study is based on 24 children and 10 adult TCPC patients aged from 5 to 41 years old. The HRQOL evaluation relies on generic self report instruments such as the PedsQL 4.0 for the children and their parents, and the Duke Health profile for the adult patients. Additional questions were specifically designed for this study as well.

RESULTS AND DISCUSSION

The estimated HRQOL is 68.15 for the children and 68.71 for their parents. In these young cases, the global HRQOL or some specific score are altered when any comorbidity or scholar difficulties are present, or when TCPC was performed more than 10 years ago. The estimated HRQOL is 74.67 in adulthood. In these patients, the young age, the lifestyle, the onset of more than 2 early complications ans the necessity of anti-arrhythmia therapy decrease various HRQOL scores. The physical handicap is considered as the major limitation for children and adult patients. Thanks to adaptative and cognitive compensatory mechanisms, such as resilience, both groups express a satisfying HRQOL assessment.

CONCLUSION

Our study indicates that TCPC provides a good HRQOL in CUHD patients despite the complex management and follow-up of these diseases, the risk of complication onset and the physical handicap usually observed.

Transcatheter Closure of Patent Foramen Ovale in Patients with Platypnea-Orthodeoxia: Results of a Multicentric French Registry

BACKGROUND

Dyspnea and the decrease in arterial saturation in the upright position in elderly subjects is described as platypnea-orthodeoxia syndrome (POS). POS is secondary to the occurrence of an atrial right-to-left shunt through a patent foramen ovale (PFO).

METHODS

This French multicentric study reports on 78 patients (mean age 67 +/- 11.3 years) with POS who had transcatheter closure of the PFO; frequently associated diseases were pneumonectomy (n = 36) and an ascending aortic aneurysm (n = 11). In all patients, the diagnosis was confirmed by transthoracic or/and transesophageal echocardiography. Five different closure devices were used: Amplatz (n = 45), Cardioseal (n = 13), Sideris (n = 11), Das Angel Wings (n = 8) and Starflex (n = 1). Closure was successful in 76 patients (97%).

RESULTS

Oxygen saturation increased immediately after occlusion from 84.6 +/- 10.7% to 95.1 +/- 6.4% (p < 0.001) and dyspnea improved from grade 2.7 +/- 0.7 to grade 1 +/- 1 (p < 0.001). A small residual shunt was immediately observed in 5 patients (3 with the Cardioseal device, 1 with the Sideris and 1 with the Amplatz) leading to the implantation of a second device in one case (Cardioseal). Two early deaths occurred unrelated to the procedure (one due to sepsis probably related to pneumonectomy, another due to respiratory insufficiency). Other complications were: a small shunt between the aorta and the left atrium, two atrial fibrillations and a left-sided thrombus which disappeared with anticoagulant therapy. At a mean follow-up of 15 +/- 12 months, there were 7 late deaths related to the underlying disease.

CONCLUSION

Percutaneous occlusion of the foramen ovale is safe and gives excellent results thanks to continuing improvement in available devices. This technique enables some patients in an unstable condition to avoid a surgical closure.

Coronary events after arterial switch operation for transposition of the great arteries

BACKGROUND

Transfer of the coronary arteries is a crucial step during the arterial switch operation (ASO) for transposition of the great arteries. This retrospective study aims to assess the incidence and risk factors of coronary events after ASO and sensitivity of noninvasive tests in the diagnosis of the coronary obstruction.

METHODS AND RESULTS

Between 1982 and 2001, 1304 newborn and infants had an ASO and the 1 198 hospital survivors had a 59-month mean follow-up. Coronary events occurred in 94 patients (7.2%; 95% CI, 6 to 9). Survival without coronary events were 92.7, 91, and 88.2% at 1, 10, and 15 years, respectively. The incidence was bimodal: high early and slow later. Multivariate analysis showed correlation with type B or C coronary pattern and major operative events (P<0.0001 and P=0.0024). In a subset of 324 patients who underwent a coronary artery angiography, lesions were observed in 22 patients (6.8%; 95% CI, 5 to 10). Multivariate analysis showed correlation with only type B or C coronary pattern (OR=20.8, P=0.0002). All of these patients had electrocardiogram and echocardiogram, 174 patients also had a treadmill test, and 115 patients had a myocardial scintigraphy. The association of these tests had the highest diagnosis sensitivity, 75%.

CONCLUSIONS

After ASO, coronary events are not rare, occurring most often early and are an important cause of death. Coronary repair can be needed lately. Noninvasive tests are not sensitive enough to detect significant delayed coronary artery stenosis and coronary artery angiography should be performed.

[Prevalence and diagnosis of coronary lesions after arterial switch]

In anatomical repair procedure of transposition of the great arteries (arterial switch), translocation of the coronary arteries is crucial and coronary complications remain the principal cause of death. The aim of this retrospective study was to assess the prevalence of coronary lesions and to evaluate the diagnostic methods to prevent their consequences. From 1982 to 2001, 1,304 patients were operated for transposition of the great arteries by the switch procedure at the Marie Lannelongue Surgical Centre. The average follow-up of the survivors was 59 months (3 days to 17 years) during which 324 patients underwent coronary angiography. All had an ECG and an echocardiogram (N = 324); 174 underwent exercise stress testing and 115 had myocardial scintigraphy. Of the 324 patients who underwent coronary angiography, 22 had coronary lesions (6.8%; 95% CI 5-10). In multivariate analysis a type II coronary network by the Marie Lannelongue Classification was related to the risk of coronary lesions (OR = 0.28; p < 0.0002). Each non-invasive method studied separately had a low sensitivity (< 50%) for the detection of these lesions. The association of ECG, echocardiography and myocardial scintigraphy had the best sensitivity at 75%. Therefore, after the arterial switch procedure non-invasive investigations are not sensitive enough to diagnose coronary lesions and systematic coronary angiography and aortography should be performed in all patients.

[Osler endocarditis of a ventricular septal defect in a 21-month old child]

The authors report a case of streptococcus mitis endocarditis of a ventricular septal defect in a 21 months old girl admitted for necrotic purpura of the lower limbs and a history of general ill health and pyrexia for two months. The severity of this case of endocarditis was illustrated by the importance of the vasculitis, the biological signs of infection (disseminated intravascular coagulation), and the size of the vegetation. The vegetation extended from the tricuspid valve as far as the pulmonary orifice which was partially obstructed, causing signs of right ventricular failure. The portal of entry was not found. Surgical ablation of the vegetation with tricuspid valvuloplasty was necessary after 48 hours of antibiotherapy. The outcome after one year's follow-up is good. The diagnosis of bacterial endocarditis must be considered even in very young children, especially those with congenital heart disease, and, in particular, ventricular septal defect.

Selective phosphodiesterase inhibitors modulate the activity of alveolar macrophages from sensitized guinea-pigs

The aim of this study was to investigate the effects of selective phosphodiesterase (PDE)3 and PDE4 inhibitors on arachidonate release by alveolar macrophages from sensitized and challenged guinea-pigs. Guinea-pigs were sensitized and challenged with ovalbumin administered by aerosol. Bronchoalveolar lavage was performed 48 h later and the PDE and cyclic adenosine monophosphate (cAMP) contents of or the arachidonate release from alveolar macrophages, stimulated in vitro with N-formyl-Met-Leu-Phe (fMLP), were evaluated. PDE3 and PDE4 activities were detected in preparations of macrophage lysate from sensitized challenged and sensitized control animals. Oral pretreatment, prior to antigen challenge in sensitized guinea-pigs, with rolipram or Ro 20-1724 (PDE4 inhibitors) but not milrinone (PDE3 inhibitor) significantly reduced the arachidonate release from alveolar macrophages. In vitro incubation of alveolar macrophages from challenged guinea-pigs with Ro 20-1724 or the cAMP analogue dibutyryl cAMP (db-cAMP) but not milrinone or the cyclic guanosine monophosphate (cGMP) analogue 8-bromo-cGMP (8-br-cGMP) significantly reduced arachidonate release. Incubation of the cells with a combination of milrinone plus rolipram or Ro 20-1724 elicited a marked and significant reduction in arachidonate release by alveolar macrophages stimulated with fMLP. In conclusion, these data show that phosphodiesterase-4 isoenzyme may regulate the release of inflammatory mediators such as arachidonate from macrophages through an increase in intracellular cyclic adenosine monophosphate. This suggests that phosphodiesterase-4 inhibitors have potential in the treatment of inflammatory disorders of the lung.

The effect of a single therapeutic dose of cisplatin on GFR in dogs

This study prospectively describes the late effect of a single dose of cisplatin on GFR in tumor-bearing dogs. GFR (measured by quantitative renal scintigraphy), BUN, creatinine, and urine specific gravity values were obtained in 19 tumor-bearing dogs prior to and four weeks after a single dose of cisplatin. Eleven tumor-bearing dogs were given a known non-nephrotoxic anticancer drug, dexniguldipine, as control. No significant differences in pretreatment GFR, serum chemistry, or urinalysis values were observed between cisplatin-treated and control dogs. GFR was significantly decreased four weeks following cisplatin administration. The average percent change in GFR was -13.49% for all cisplatin treated dogs. No significant alterations of BUN, serum creatinine, or urine specific gravity were observed following treatment. In the control group, the average percent change in GFR was +3.98% which was not significantly different from pretreatment values.

Effect of hyperthermia on normal tissue toxicity and on adriamycin pharmacokinetics in dogs

This study examined the effects of Adriamycin (ADR) (30 mg/m2), whole-body hyperthermia (WBH) (42 degrees C for 1 h), and the combination of the two (ADR plus WBH) on gastrointestinal and hematopoietic toxicity and the effects of WBH on ADR pharmacokinetics in the normal dog (n = 5/treatment group). Duodenal biopsies were collected from animals in each group via endoscopy and were incubated in the presence of [3H]thymidine as an index of cell turnover. Additional duodenal biopsies were assayed for the enzymes gamma-glutamyltranspeptidase, N-acetyl-beta-D-glucosaminidase, and succinate dehydrogenase. Complete blood chemistry profiles and differential blood cell counts were done prior to and following treatment. Cell turnover was most depressed 3 days after ADR or ADR plus WBH; WBH alone had little effect on cell turnover. Neither gamma-glutamyltranspeptidase, N-acetyl-beta-D-glucosaminidase, nor succinate dehydrogenase activities were significantly altered by any of the treatment protocols. High performance liquid chromatography was used to quantify Adriamycin and adriamycinol in samples collected up to 6 h after drug administration. Duodenal biopsies were collected immediately and 1 h after drug administration for measurement of tissue concentrations of Adriamycin. A significant increase in the apparent volume of distribution and whole-body clearance and decrease in area under the plasma Adriamycin concentration versus time curve occurred when drug was administered concurrently with WBH. This differs from results reported in some other mammalian species.

Origin and trajectory of the cerebello-olivary projection: an experimental study with radioactive and fluorescent tracers in the cat

It was demonstrated with autoradiographic methods that a tract of thin fibers, which is for the most part distinct from the brachium conjunctivum and its crossed descending limb, can be followed from the cerebellar nuclei to the inferior olive. Neurons from all regions of the interposed and dentate nuclei contribute to this tract. With two fluorescent tracers, Fast Blue and Diamidino Yellow Dihydrochloride, the perikarya of neurons in the cerebellar nuclei that project to the inferior olive or thalamus were identified and the possibility of collateral projections from single neurons to both regions was investigated. Numerous retrogradely labeled neurons were seen in the contralateral interposed and dentate nuclei but no double-labeled cells were ever encountered. The mean diameters of the cells projecting to the inferior olive were between 15 and 20 microns while the mean diameters for those projecting to the nucleus ventrolateralis of thalamus were between 25 and 35 microns. Differences in the morphology of the two cell populations were noted. It was also found that the fastigio-olivary projection is small, terminating mainly contralaterally, in the caudal medial accessory olive and subnucleus beta. It is concluded that cerebello-olivary fibers are not collaterals of the cerebellothalamic projection and that there are two different populations of neurons in the cerebellar nuclei that give rise to these distinct efferent projections.

Cerebellar nucleocortical projection with a survey of factors affecting the transport of radioactive tracers

The nucleocortical projection has been studied with the method of anterograde transport of tritiated amino acids and autoradiography. It was observed that this projection is made up of a small number of fibers. Counts of silver grain aggregates in projection sites of the granular layer were compared with counts from material on the cuneocerebellar projection. As it had been concluded in previous studies that the projection is quantitatively important, several modifications of the experimental conditions were tested. Radioactive leucine of high or low specific activity as well as a mixture of amino acids were used. It was observed that labeling is always more intense with a high specific activity tracer. Variations of the aspect and density of the projection were observed with survival periods lasting from a few hours to several days. With survival times between 9 and 15 hours, round aggregates of silver grains measuring from 10 to 20 microns were observed in the granular layer of labeled regions. At longer survival periods, the terminal structures in the granular layer appeared as coarse linear aggregates. It is suggested that the latter represent preterminal labeled fragments while the round accumulations correspond to terminal rosettes. Maximum density of the labeling in the granular layer occurred between 9 and 15 hours. At 2 days, the density was lowest, and at 5 or 6 days it was somewhat higher. Even under optimal conditions, the density of the nucleocortical terminals was low.

Detailed organization of cerebello-olivary projections in the cat. An autoradiographic study

Several small injections of tritiated leucine were placed in regions of the cerebellar nuclei and sites of distribution in the olive were revealed by autoradiography. Different survival periods from a few hours to several days were utilized and high or low specific activity tracers were evaluated. A general pattern of distribution whereby the dentate, anterior and posterior interposed respectively project to principal, dorsal accessory and medial accessory olives was confirmed. Several new details of distributions from regions of the interposed and dentate nuclei to parts of the olivary subdivisions were demonstrated. The pattern of representations is complex and distributed in three dimensions. It is very precise and approximates a point to point representation. However, these projections which appear relatively dense do not represent the only link between the cerebellar nuclei and olive. With survival periods of a few hours, additional lighter projections distributed according to a different pattern can be revealed. A small ipsilateral projection was observed and it is suggested that it is made of collaterals of the crossed fibers.

Humoral regulation of erythropoiesis in cats: preliminary report

Cats were subjected to acute or subacute phlebotomy regimens in a study to investigate the humoral regulation of erythropoiesis as mediated by erythropoietin. The erythropoietic effects of the acute phlebotomy regimen were similar to those effects of the subacute regimen. serum erythropoietin in cats was increased for at least 10 days after initiating the phlebotomies.