Arrhythmia burden, rhythm interventions and outcome in a large Swiss multicenter population of d-TGA patients with atrial switch

Funding Acknowledgements

Type of funding sources: None.

Background

Patients with dextro-transposition of the great arteries (d-TGA) and atrial switch face a high life-time risk of arrhythmias.

Purpose

To describe the incidence of arrhythmias, associated cardiac interventions and outcome in a large Swiss population of patients with d-TGA and atrial switch.

Methods

In this multicenter analysis we included all consecutive patients with d-TGA and atrial switch treated at three Swiss tertiary care hospitals. The primary outcome was survival free from left ventricular assist device (LVAD), heart transplantation (HTx) and death. The secondary outcome was survival free from ventricular tachycardia, ventricular fibrillation and sudden cardiac death.

Results

We identified 207 patients (34% females; median age at last follow-up 35 years) with d-TGA and atrial switch. Arrhythmias occurred in 97 patients (47%) at a median age of 22 years. A pacemaker or an implantable cardioverter/defibrillator was implanted in 39 (19%) and 13 (6%) patients, respectively, and 33 (16%) underwent a total of 51 ablation procedures to target 60 intra-atrial reentry tachycardias, 4 AV nodal reentry tachycardias and one atrial fibrillation (Figure 1). The primary outcome occurred in 21 patients (10%) and the secondary outcome in 18 (9%) (Figure 2). Primary and secondary outcomes were more common in patients with concomitant ventricular septum defect (VSD) than in those without (hazard ratio [HR] 3.06; 95% confidence interval [CI] 1.29-7.27, p=0.011; and HR 3.62; 95% CI 1.43-9.18, p=0.007, respectively).

Conclusions

At a median age of 35 years, arrhythmias occur in almost half of patients with d-TGA and atrial switch and associated rhythm interventions are frequent. One in ten patients does not survive free from LVAD and HTx and outcome is worse in patients with concomitant VSD.

Reproductive history and osteoarthritis in the Women's Health Initiative

Objective: To investigate the relationship between self-reported osteoarthritis (OA) and reproductive factors in the Women's Health Initiative (WHI). Method: We used multivariable logistic regression to study the association of self-reported OA and reproductive factors in the WHI Observational Study and Clinical Trial cohorts of 145 965 postmenopausal women, in a retrospective cross-sectional format. Results: In our cohort, we observed no clinically significant associations between reproductive factors and OA given small effect sizes. The following factors were associated with statistically significant increased likelihood of developing OA: younger age at menarche (p < 0.001), history of hysterectomy [adjusted odds ratio (aOR) 1.013, 95% confidence interval (CI) 1.004-1.022, p = 0.04 vs no hysterectomy], history of unilateral oophorectomy (aOR 1.015, 95% CI 1.004-1.026, p < 0.01 vs no oophorectomy), parity (aOR 1.017, 95% CI 1.009-1.026, p < 0.001), ever use of oral contraceptives (aOR 1.008, 95% CI 1.001-1.016, p < 0.01 vs never use), and current use of hormonal therapy (reference current users, aOR 0.951, 95% CI 0.943-0.959 for never users; aOR 0.981, 95% CI 0.972-0.989 for past users; global p < 0.001). Age at menopause, first birth, and pregnancy were not associated with OA. Among parous women, no clear pattern was observed with number of pregnancies, births, or duration of breastfeeding in relation to OA. Conclusion: Our study showed that reproductive factors did not have significant clinical associations with OA after controlling for confounders. This may be due to complex hormonal effects. Additional investigation is warranted in prospective cohort studies. The Women's Health Initiative is registered under ClinicalTrials.gov. Trial registration ID: NCT00000611.

Calibration to American options: numerical investigation of the de-Americanization method

American options are the reference instruments for the model calibration of a large and important class of single stocks. For this task, a fast and accurate pricing algorithm is indispensable. The literature mainly discusses pricing methods for American options that are based on Monte Carlo, tree and partial differential equation methods. We present an alternative approach that has become popular under the name de-Americanization in the financial industry. The method is easy to implement and enjoys fast run-times (compared to a direct calibration to American options). Since it is based on ad hoc simplifications, however, theoretical results guaranteeing reliability are not available. To quantify the resulting methodological risk, we empirically test the performance of the de-Americanization method for calibration. We classify the scenarios in which de-Americanization performs very well. However, we also identify the cases where de-Americanization oversimplifies and can result in large errors.

TAPP or TEP for Recurrent Inguinal Hernia? Population-Based Analysis of Prospective Data on 1309 Patients Undergoing Endoscopic Repair for Recurrent Inguinal Hernia

BACKGROUND

Whether total extraperitoneal inguinal hernia repair (TEP) is associated with worse outcomes compared to transabdominal preperitoneal inguinal hernia repair (TAPP) for the treatment of recurrent inguinal hernia continues to be a matter of debate. The objective of this large cohort study is to compare complications, conversion rates and postoperative length of hospital stay between patients undergoing TEP or TAPP for unilateral recurrent inguinal hernia repair.

METHOD

Based on prospective data of the Swiss Association of Laparoscopic and Thoracoscopic Surgery, all patients who underwent elective TEP or TAPP for unilateral recurrent inguinal hernia between 1995 and 2006 were included. The following outcomes were compared: conversion rates, intraoperative complications, surgical postoperative complications and duration of operation.

RESULTS

Data on 1309 patients undergoing TEP (n = 1022) and TAPP (n = 287) for recurrent inguinal hernia were prospectively collected. Average age, BMI and ASA score were similar in both groups. Patients undergoing TEP had a significantly increased rate of intraoperative complications (TEP 6.3 % vs. TAPP 2.8 %, p = 0.0225). Duration of operation was longer for patients undergoing TEP (TEP 80.3 vs. TAPP 73.0 min, p < 0.0023) while postoperative length of hospital stay was longer for patients undergoing TAPP (TEP 2.6 vs. TAPP 3.1 day, p = 0.0145). Surgical postoperative complications (TEP 3.52 % vs. TAPP 2.09 %, p = 0.2239), general postoperative complications (TEP 1.47 % vs. TAPP 0.7 %, p = 0.3081) and conversion rates (TEP 2.15 % vs. TAPP 1.39 %, p = 0.4155) were not significantly different.

CONCLUSION

This study is the first population-based analysis comparing outcomes of patients with recurrent inguinal hernia undergoing TEP versus TAPP in a prospective cohort of over 1300 patients. Intraoperative complications were significantly higher in patients undergoing TEP. The TEP technique was associated with longer operating times, but a shorter postoperative length of hospital stay. Nonetheless, the absolute outcome differences are small and thus, on a population-based level, both techniques appear to be safe and effective for patients undergoing endoscopic repair for unilateral recurrent inguinal hernia.

Magnetic films on nanoperforated templates: a route towards percolated perpendicular media

We present a study on the magnetization reversal in Co/Pt multilayer films with an out-of-plane easy axis of magnetization deposited onto substrates with densely distributed perforations with an average period as small as 34 nm. Deposition of magnetic Co/Pt multilayers onto the nanoperforated surface results in an array of magnetic nanodots surrounded by a continuous magnetic film. Following the evolution of the magnetic domain pattern in the system, we suggest that domain walls are pinned on structural inhomogeneities given by the underlying nanoperforated template. Furthermore, a series of micromagnetic simulations was performed in order to understand the modification of the pinning strength of domain walls due to the magnetic interaction between nanodots and the surrounding film. The results of the simulations show that magnetic exchange coupling between the nanodots and the surrounding film strongly influences the pinning behavior of the magnetic domain walls which can be optimized to provide maximal pinning.

Non-small cell lung cancer and estrogen plus progestin use in postmenopausal women in the Women's Health Initiative randomized clinical trial

CRA1500

Background: Sex differences in lung cancer outcome suggest a potential hormonal influence; however, observational studies provide mixed findings regarding menopausal hormone therapy (HT) and lung cancer. Methods: Secondary analyses of the WHI randomized, placebo-controlled trial of daily conjugated equine estrogen (CEE, 0.625 mg) plus medroxyprogesterone acetate (MPA, 2.5 mg) in 16,608 multi-ethnic postmenopausal women, aged 50–79 were conducted on lung cancer incidence and mortality. Lung cancers were confirmed by medical record review. Results: Groups were balanced for age, race/ethnicity, and prior HT. Smoking status was also comparable (never 50%, past 40%, current 10% in both groups). Cumulative risk for lung cancer was highest in current (0.51%), compared to past (0.14%) and never (0.04%) smokers. After 5.6 years on trial intervention and 2.4 years additional follow-up (median), small cell lung cancer incidence was comparable between randomization groups (total n=26), as was subsequent small cell lung cancer mortality. Although a trend for more non-small cell lung cancer (NSCLC) diagnoses in the active hormone group was not significant (p=0.12), an apparent divergence emerged after five years, with more diagnoses in the CEE+MPA group. In addition, mortality after NSCLC diagnosis was significantly higher for the CEE+MPA group (46.3% vs 27.0%, respectively, hazard ratio (HR) 1.59, 95% CI 1.03–2.46, p=0.04). As a result, CEE+MPA group women were more likely to die from NSCLC than those on placebo (p=0.02). Conclusions: Use of CEE + MPA for over 5 years increases a woman's risk for NSCLC mortality, the leading cause of cancer death in women. These data, together with recent results indicating higher breast cancer risk (Cancer Res 2009;69(2):78s), suggest cancer impact should influence risk-to-benefit consideration for combined HT use.

[Table: see text]

[Table: see text]

Non-small cell lung cancer and estrogen plus progestin use in postmenopausal women in the Women's Health Initiative randomized clinical trial

CRA1500

The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

[Table: see text]

The diagnostic yield from implantable loop recorders in children and young adults

BACKGROUND

Syncope and palpitations occur frequently in young patients. Noninvasive diagnostic testing may be inconclusive.

AIM

To assess the diagnostic yield of implantable loop recorders in young patients.

PATIENTS AND METHODS

Thirty-three young patients underwent implantation of a loop recorder for long-term monitoring of cardiac rhythm, to establish symptom-rhythm correlation. They belonged to one of three subgroups: those with structurally normal heart, normal electrocardiogram at rest, and negative family history (n = 16); patients with structural heart disease and previous surgical repair (n = 11), and patients with proven or suspected primary electrical disease (n = 6). A combination of automatic and patient-activated recordings was used to monitor cardiac rhythm during symptomatic episodes.

RESULTS

There were no procedural complications. Diagnostic electrograms could be obtained in all patients. A high degree of symptom-rhythm correlation was established. In 8/33 patients, no recurrence of symptoms was observed either until end of battery life of the device (n = 4) or until last follow-up (n = 2). Specific cardiac therapy was required, based on rhythms recorded by the device in 15 patients (until last follow-up). This consisted of catheter ablation of a tachyarrhythmia (n = 7), pacemaker implantation or upgrade (n = 5) or ICD implantation (n = 5). In the remaining patients (n = 10), recurrence of symptoms was associated with a normal electrocardiogram, and in two of these patients a non-cardiac diagnosis was made.

CONCLUSIONS

In selected patients, the implantable loop recorder provides valuable diagnostic information to guide further therapy.

ICD-Schrittmachertherapie bei Kindern und Jugendlichen

BACKGROUND

The compelling safety and efficacy data in numerous large, blinded trials on adult patients, and the progress in device- and leadtechnology have led to increasing use of implantable cardioverter defibrillators in pediatric patients. The purpose of our study was to assess the efficacy and safety of ICD in the pediatric age group of a tertiary referral centre.

PATIENTS AND METHODS

Between March 1998 and October 2003 12 patients underwent ICD-implantation. The mean age at implantation was 14,8 years with a range between 10-17 years. The underlying cardiac disorders included long QT-syndrome in 4 patients, ventricular fibrillation in 3 patients, dilated cardiomyopathy in 4 patients, and congenital heart disease in 1 patient (pulmonary atresia with ventricular septal defect after Rastelli repair). All patients received a transvenous ICD-system (VVI-ICD in 4 patients, DDD-ICD in 8 patients).

RESULTS

The mean follow up was 35 months (6-68 months). During this period there were no severe complications nor mortality. We haven't seen infections, thromboembolic complications or lead-perforations. 2 patients (17 %) received appropriate DC-shocks, 1 patient (8 %) received an inappropriate DC-shock. 10 patients (83 %) had no malignant ventricular arrhythmia under medical therapy. 2 patients (17 %) required revision because of lead-dysfunction. In 2 patients with DCM the device was explanted during orthotopic heart transplantation.

CONCLUSIONS

Our data demonstrate that advances in device- and leadtechnology have resulted in a decrease of severe complications in the pediatric age group. We conclude that ICD-implantation represents a safe and effective therapy for children and adolescents with lifethreatening ventricular dysrhythmias. Since it represents an invasive therapy, indication should be confined to patients with lifethreatening dysrhythmias according to the guidelines of the American Heart Association.

Recanalisation of bilateral superior vena cava after total cavopulmonary connection. Interventional occlusion with the Amplatzer VSD Occluder

Formation of systemic to pulmonary venous or systemic venous left atrial collaterals frequently occurs in patients after Glenn or Fontan-type operations. Embolization with detachable metal coils is the therapy of choice for the closure of small vessels. These devices however are not appropriate for the occlusion of large collaterals, e. g. recanalized bilateral caval veins. We report two patients who presented late after Fontan-type operations with a gradual decrease in oxygen saturation due to recanalisation of bilateral caval veins. Interventional closure of these large veins was carried out successfully with the use of 8 mm Amplatzer muscular VSD Occluders, resulting in an increase of arterial oxygen saturations.

CONCLUSION

The closure of recanalized bilateral superior caval veins after Fontan procedures is possible without technical problems by means of the Amplatzer muscular VSD Occluder. In order to avoid future formation of venous collaterals via the azygos or hemiazgos system, the occluder should be placed in the vena cava below the orifice of the azygos/ hemiazygos vein.

[Atrial tachycardia, atrial flutter, atrial fibrillation: curative therapy by focal ablation in a pulmonary vein]

We describe the case of a 50-year-old woman with the clinical diagnosis of cardiomyopathy associated with supraventricular tachycardia refractory to pharmacological treatment. The totally irregular tachyarrhythmia was the result of different episodes of atrial tachycardia, atrial flutter and atrial fibrillation that could be identified in the surface ECG. These findings and the patient's symptoms were all caused by a single focal tachycardia originating from the left upper pulmonary vein. Ablation of this focus represented a curative antiarrhythmic therapy also restoring a normalized ventricular function. Thus, an ablation of the AV node with consecutive pacemaker implantation could be prevented.

Hormone replacement for the new millennium

The field of hormone replacement therapy continues to evolve. Guidelines and dosing regimens change in response to new data and treatment options. It is important for the clinician to remain informed to be able to interpret new findings for the patient.

Technical considerations for inhaled nitric oxide therapy: time response to nitric oxide dosing changes and formation of nitrogen dioxide

The aim of the present study was to analyse the time response to nitric oxide (NO) dosing changes as well as the formation of nitrogen dioxide (NO2) with different ventilation systems, respirator settings and application sites during NO inhalation. The inspired NO and NO2 concentrations were continuously measured using chemiluminiscence within a dummy ventilatory system equipped with two different respirator systems (Siemens Servo 900c and Bear BP 2001). NO was either introduced into the afferent limb of the ventilatory circuit close to the endotracheal tube (site A) or into the so-called low pressure port of the Servo 900c respirator, far away from the endotracheal tube (site B). In addition, the decay of the inspired NO concentration after cessation of the NO gas flow was studied. This decay was considerably prolonged when NO was introduced at site B (time constants: tau = 7.19 min versus tau = 0.29 min). Within the concentration range studied (0-25 ppm NO) a linear correlation between the NO and NO2 concentration was found. At site A and an inspired oxygen concentration of > 0.95 NO2 formation amounts to 1.14% +/- 0.11% of the NO concentration. Using this value one can calculate the NO2 formation for a given NO dose. For example, when 40 ppm NO are applied, a concentration of 0.45 ppm NO2 can be expected, which is well below the relevant toxic concentrations. However, when NO was introduced at site B, NO2 formation was significantly increased to 1.61% +/- 0.16%. Passage of the ventilated gas through soda lime led only to a slight and insignificant reduction in NO2 concentration. The continuous flow respirator BP 2001 showed a significantly lower NO2 concentration when compared to the non-continuous flow respirator Servo 900c (0.64 +/- 0.11% vs.1.14 +/- 0.11%).

CONCLUSION

The application of NO close to the endotracheal tube is associated with a much faster response of the actual inspired NO concentration to dosing changes and shows the lowest NO2 formation. In order to avoid toxic NO2 concentrations, an upper limit of 40 ppm NO is recommended for continuous NO inhalation.