Publications by authors named "Matthias Gass"

15 Publications

  • Page 1 of 1

Radiofrequency catheter ablation for supraventricular tachycardia in a paediatric population: characteristics of tachycardia mechanisms in a subpopulation with early onset.

Cardiol Young 2020 Oct 25;30(10):1383-1388. Epub 2020 Sep 25.

Paediatric Cardiology, Paediatric Heart Center, Department of Surgery, University Children's Hospital, Steinwiesstr. 75, 8032Zurich, Switzerland.

Background: In children, the first episode of supraventricular tachycardia occurs at various ages. The aim of this study is to describe age-specific tachycardia mechanisms, clinical findings, and outcome in a contemporary cohort of paediatric patients with supraventricular tachycardia.

Methods: Retrospective analysis of 531 consecutive patients with structurally normal hearts under the age of 18 years who underwent invasive electrophysiological study for supraventricular tachycardia. The study population was divided into two groups, early-onset group (n = 57) and late-onset group (n = 474), according to the age of the occurrence of the first tachycardia before or after the age of 12 months.

Results: Accessory pathway-mediated tachycardia was more common (82.5 versus 50.1%, p < 0.001) and the proportion of left-sided accessory pathways was more pronounced (74.5 versus 53.7%, p = 0.01) in the early-onset group than in the late-onset group. The antegrade and retrograde refractory periods of the accessory pathways were similar in both groups, but pre-excitation was more common in the early-onset group (50.9 versus 31.9%, p = 0.007). Typical atrioventricular nodal re-entrant tachycardia was more common (36.7 versus 7.0%, p < 0.001) in the late-onset group. There was no difference among the two groups regarding overall outcome.

Conclusion: Accessory pathway-mediated re-entrant tachycardia is the most common mechanism of recurrent supraventricular tachycardia in infants with structurally normal hearts who are later referred to an electrophysiological study. These pathways often cause pre-excitation and tend to be located on the left side whereas their refractory period is not different from that of patients with late-onset tachycardia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1017/S1047951120002954DOI Listing
October 2020

Pacemaker Implantation in Neonates and Infants: Favorable Outcomes with Epicardial Pacing Systems.

Pediatr Cardiol 2020 Jun 27;41(5):910-917. Epub 2020 Feb 27.

Department of Surgery, Pediatric Cardiology, Pediatric Heart Center, University Children's Hospital, Steinweisstrasse 75, 8032, Zurich, Switzerland.

The implantation of pacemakers (PM) in neonates and infants requires particular consideration of small body size, marked body growth potential, and the decades of future pacing therapy to be expected. The aim of this study is to quantify the complications of implantation and outcome occurring at our center and to compare these with other centers. Retrospective analysis of 52 consecutive patients undergoing PM implantation at a single tertiary care center within the first year of life. PMs were implanted at a median age of 3 months (range 0-10 months). Structural heart defects were present in 44 of 52 patients. During a median follow-up time of 40.4 months (range 0.1-114 months), measurements for sensing, pacing thresholds, and lead impedance remained stable. No adverse pacing effect was observed in left ventricular function or dimensions over time. There were 20 reoperations in 13 patients at a median time of 4.7 years (range 0.05-8.2 years) after implantation, for end of battery life (n = 10), lead dysfunction (n = 3), device dislocation (n = 3), infection (n = 3), and diaphragmatic paresis (n = 1). No PM-related mortality occurred. Epicardial pacemaker implantation in neonates and infants is an invasive but safe and effective procedure with a relatively low risk of complications. Our current implantation technique and the use of bipolar steroid-eluting electrodes, which we prefer to implant on the left ventricular apex, lead to favorable long-term results.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00246-020-02332-zDOI Listing
June 2020

Magnetic resonance imaging of patients with epicardial leads: in vitro evaluation of temperature changes at the lead tip.

J Interv Card Electrophysiol 2019 Dec 12;56(3):321-326. Epub 2019 Nov 12.

Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, 8092, Zürich, Switzerland.

Purpose: The aim of this study was to systematically investigate the potential heating effects of magnetic resonance imaging (MRI) in the presence of epicardial leads, which are connected to a device or abandoned, using a series of in vitro measurements.

Methods: The heating effects of MRI in a 1.5-T scanner were measured at the lead tip in a gel-filled tank. First, a transvenous lead (5086-45 cm, Medtronic) was compared with an epicardial lead (4968-35 cm, Medtronic) with and without connection to an MR-conditional pacemaker. Then, experiments were conducted using various lengths of epicardial leads exposed to MRI.

Results: (1) A temperature rise of + 2.5 °C was observed for the transvenous lead attached to an MRI-conditional pacemaker. The epicardial lead attached to the same pacemaker showed four times higher heating. (2) The transvenous lead without pacemaker showed four times higher heating, and the epicardial lead without pacemaker showed 30 times higher heating. (3) The epicardial lead coiled to 20 cm length without pacemaker showed 9 times higher heating. (4) Experiments with various lengths of epicardial leads showed that the shorter the leads were, the smaller was the heating effect.

Conclusion: Standard clinical MRI investigations may result in pronounced heating at the tip of epicardial electrodes. Epicardial leads, which are not connected to a pacemaker and thus mimicking abandoned leads, may even result in a more pronounced rise in temperature at the lead tip. Therefore, current epicardial pacing systems may carry a substantial risk of inducing thermal damage of the neighboring tissue during MRI scanning.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-019-00627-7DOI Listing
December 2019

Long-term outcome of epicardial implantable cardioverter-defibrillator systems in children: results justify its preference in paediatric patients.

Europace 2018 09;20(9):1484-1490

Departments of Cardiology, Pediatric Heart Centre, University Children's Hospital Zurich, Steinwiesstr. 75, Zurich, Switzerland.

Aims: The question of whether transvenous or epicardial implantable cardioverter defibrillator (ICD) system is more beneficial in children and adolescents is controversially discussed. We sought to analyse the long-term outcome after implantation of ICDs using epicardial pacing/sensing and pleural shock leads.

Methods And Results: Retrospective analysis of 31 consecutive patients undergoing a total of 55 implantations of epicardial/pleural ICD systems below 20 years of age. Median age at implantation was 11.4 years (range 2.2-20) and median follow-up 57 months (range 0.4-127). The ICDs were implanted for primary (n = 17) and for secondary prevention (n = 14). The first defibrillation threshold at implantation was ≤25 J in 94% of the implant procedures. Appropriate shocks occurred in 6 of 31 patients. Inappropriate shocks occurred in 4 of 31 patients triggered by lead fracture, T-wave oversensing, sinus tachycardia, and atrial fibrillation. Freedom from first ICD discharge was 81, 71, and 71% at 3, 6, and 9 years, respectively. Reoperation was indicated in 16 of 31 patients for lead failure (n=11), end of battery life (n=10), generator migration (n=1) and recall (n=1); freedom from reoperation was 74 and 55% at 3 and 6 years.

Conclusion: Paediatric epicardial/pleural ICD therapy is feasible, effective, and safe both in the short-term as well as in the long-term perspective at the price of relatively frequent surgical revisions. They do not generally result in an increased burden of inappropriate shocks. This ICD system meets the needs of the paediatric population and can be recommended as a first choice in this age group.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/europace/eux284DOI Listing
September 2018

CME-EKG 58/Auflösung.

Praxis (Bern 1994) 2017 Sep;106(18):1016-1020

1 Klinik für Kardiologie, Universitäres Herzzentrum, Universitätsspital Zürich.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1024/1661-8157/a002790DOI Listing
September 2017

CME-EKG 58.

Praxis (Bern 1994) 2017 Aug;106(17):919-920

1 Klinik für Kardiologie, Universitäres Herzzentrum, Universitätsspital Zürich.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1024/1661-8157/a002789DOI Listing
August 2017

Management of postoperative junctional ectopic tachycardia in pediatric patients: a survey of 30 centers in Germany, Austria, and Switzerland.

Eur J Pediatr 2017 Sep 21;176(9):1217-1226. Epub 2017 Jul 21.

Department of Pediatric Cardiology, University of Leipzig, Heart Center, Strümpellstrasse 39, 04289, Leipzig, Germany.

Postoperative junctional ectopic tachycardia (JET) is a frequent complication after pediatric cardiac surgery. Current recommendations on how and when to treat JET are inconsistent. We evaluated the management strategies of postoperative JET in German-speaking countries. We sent an online survey to 30 centers of pediatric cardiology that perform surgery for congenital heart defects in Germany (24), Austria (4), and Switzerland (2). The survey asked 18 questions about how and in what treatment sequence postoperative JET was managed. All 30 centers completed the survey (100% return rate). There was general agreement that the management of JET is based on administration of antiarrhythmic drugs, body surface cooling, and temporary pacing. Many centers presented treatment algorithms based on published literature, all centers named amiodarone as the first drug of choice. Significant disagreement was found concerning the timing and sequential order of additional therapeutic measures and particularly about the dosing of amiodarone and the role of R-wave synchronized atrial pacing.

Conclusion: This survey reveals that from center to center, the treatment of postoperative JET may vary substantially. Future work should focus on those treatment modalities where a high rate of variation is found. Such studies may be of value to achieve commonly adopted treatment recommendations. What is known: • Treatment of postoperative junctional ectopic tachycardia is predominantly based on administration of antiarrhythmic drugs, therapeutic cooling, and temporary pacing. • Amiodarone is the antiarrhythmic drug of choice in this context. What is new: • Dosing and duration of administration of amiodarone differ relevantly from center to center. • The sequential order of drug administration, therapeutic cooling, and pacing is not consistent.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00431-017-2969-xDOI Listing
September 2017

Transseptal puncture for radiofrequency catheter ablations of left-sided arrhythmias in a paediatric population.

Cardiol Young 2017 Mar 18;27(2):267-272. Epub 2016 Apr 18.

1Department of Paediatric Cardiology,University Children's Hospital Zurich,Zürich,Switzerland.

Puncturing the atrial septum is frequently used in adults. In children, the transseptal puncture is less common, technically more demanding, and the rate of complications is not well described. We studied the feasibility and safety of this procedure in a retrospective analysis of 157 consecutive children undergoing transseptal puncture for radiofrequency catheter ablation of left atrial targets in two tertiary-care centres between 2005 and 2013. The median age of the patients at intervention was 12.5 years (1.1-18 years), with median weight of 42 kg (range 9.0-97.0 kg). Pre-excitation was found in 102 procedures, accessory pathway with exclusively retrograde conduction in 41, focal atrial tachycardia in nine, left-sided permanent junctional/reciprocating tachycardia-like accessory pathways in three, and atypical atrioventricular nodal re-entry tachycardia in two. All the procedures were guided by fluoroscopy. Additional imaging by transoesophageal echocardiography was used in three patients. Successful transseptal puncture was possible in 99.4% of the cases, ablation in 97.4%. The median time, including mapping and radiofrequency ablation, was 120 minutes (range 60-450), the median fluoroscopy time 10.8 minutes (range 1.8-75), and the median radiation dose 3 Gy cm2 (range 0.3-35). In total, five patients (3.2%) had a recurrent arrhythmia during the observation period of a median of 40 months (range 1-103). No complications associated with the transseptal puncture were observed. Transseptal puncture is a feasible and safe procedure in children. This access allows successful and efficient radiofrequency ablation of arrhythmia of the left atrium in the vast majority of the patients and might be considered as the first-line approach in this population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1017/S1047951116000457DOI Listing
March 2017

Postoperative arrhythmia in patients with bidirectional cavopulmonary anastomosis.

Eur J Cardiothorac Surg 2014 Apr 19;45(4):620-4. Epub 2013 Aug 19.

Department of Cardiology, University Children's Hospital Zurich, Zürich, Switzerland.

Objectives: Bidirectional cavopulmonary anastomosis (BDCPA) is part of the staged Fontan palliation for congenital heart defects with single-ventricle morphology. The aim of this study was to describe incidence and characteristics of early postoperative arrhythmias in patients undergoing BDCPA.

Methods: Retrospective analysis of 60 patients undergoing BDCPA at the age of <12 months from 2001 to 2008 at a single centre. Arrhythmias were subclassified in sinus bradycardia, premature atrial/ventricular contraction, supraventricular tachycardia and atrioventricular block. The groups were compared according to age at operation and diagnosis. Postoperative follow-up data were included until Fontan completion.

Results: Postoperative arrhythmia was observed in 20 patients: 12 temporary and 8 persisting until hospital discharge. Sinus bradycardia is a common postoperative arrhythmia and occurred in 16 patients (9 transient, 7 persistent until hospital discharge). One patient undergoing BDCPA and a Damus-Kaye-Stansel procedure had a persisting first-degree atrioventricular block. The occurrence of a postoperative arrhythmia was independent of age and diagnostic group (hypoplastic left heart vs non-hypoplasic left heart). After hospital discharge, five of the eight arrhythmia resolved spontaneously resulting in 2 patients with sinus bradycardia and 1 patient with a first-degree AV block immediately before the Fontan completion was undertaken.

Conclusions: Postoperative arrhythmias in patients with BDCPA occur early after surgery and are temporary. Severe and life-threatening arrhythmias are rare although the interventions are complex and the patients very young. The most common arrhythmia is sinus bradycardia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/ejcts/ezt420DOI Listing
April 2014

Surgical correction of scoliosis in children with congenital heart failure (Fontan circulation): case report and literature review.

Eur Spine J 2008 Sep 29;17 Suppl 2:S312-7. Epub 2008 Jan 29.

Department of Orthopaedic Surgery, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076, Tuebingen, Germany.

Patients with Fontan circulation represent a significant cardiorespiratory risk during spinal surgery. We report about two patients with severe scoliosis and Fontan circulation and their successful operative treatment. The case report will be compared with the national and international literature.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00586-008-0597-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2525900PMC
September 2008

Use of the implantable loop recorder in children and adolescents.

Cardiol Young 2006 Dec;16(6):572-8

Department of Pediatric Cardiology, Children's Hospital, University of Tuebingen, Tuebingen, Germany.

Introduction: Recurrent but infrequent syncopes represent a diagnostic challenge, since they frequently remain unexplained despite extensive investigations. This applies specifically for patients who carry an increased risk of potentially lifethreatening arrhythmias, either due to congenital cardiac disease or primary electrical disorders. Implantable loop recorders permit long-term electrocardiographic monitoring. Experience with these devices is still limited in children.

Patients And Methods: Between January 1999 and August 2005, 12 patients underwent implantation of a loop recorder in our tertiary referral centre. The mean age was 10.9 years, with a range from 2 to 17 years. Of the patients, 6 had structural disease, 3 had primary electrical abnormalities, and 3 had no cardiovascular disease.

Results: Resyncope occured in 9 of the 12 patients. Arrhythmic origin of the syncope was diagnosed in 4 of these patients. The events recorded were ventricular fibrillation in 2, intermittent asystole in 1, and pacemaker-syndrome in the other patient. Malignant arrhythmia was ruled out in the remaining 5 patients. There were no complications related to implantation of the loop recorder, and the mean duration until explantation was 8.3 months.

Conclusions: Based on our experience, we suggest that implantation of a loop recorder represents an additional tool for a selected group of children. Due to its invasive nature, it should be restricted to patients at high risk, or those in which there is substantial clinical suspicion of the likelihood of serious arrhythmias when conventional testing has been inconclusive. In this cohort, implantation of the loop recorder either helps to establish the correct diagnosis, or to exclude an arrhythmic event, thus avoiding unnecessary escalation of therapy and providing reassurance for the family.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1017/S1047951106001156DOI Listing
December 2006

Anomalous origin of left coronary artery in young athletes with syncope.

BMJ 2006 May;332(7550):1139-41

Department of Pediatric Cardiology, Pulmonology and Intensive Care, Universitätsklinikum Tübingen, Tübingen, Germany.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/bmj.332.7550.1139DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1459601PMC
May 2006

Fractally coated myocardial pacemaker leads in children.

J Interv Card Electrophysiol 2005 Oct;14(1):37-43

Pediatric Cardiology, Children's Hospital, University of Tuebingen, Germany.

Unlabelled: We report our single centre experience with a new fractally coated myocardial unipolar lead (ELC35UP; Biotronik) in 96 pediatric patients (59% male, 41% female). Congenital heart disease (CHD) was associated in 89%. The age at implantation ranged between 2 days and 19 years, median for children with CHD 7.8 years, without CHD 4.7 years. Twenty percent of the children were younger than one year at implantation. Mean follow-up was 30 months (1-57 months). We compared our findings with a steroid eluting epicardial lead (CapSure EPI 4968; Medtronic) in 46 children with comparable age and sex-distribution. We found a lead survival of 87% after 57 months in the ELC35UP group (steroid lead: 87% after 129 months). Pacing energy thresholds were equal after 12 months (median 3.0 microjoules), but the sensing characteristics of the fractally coated lead was significantly superior to the steroid eluting lead with median R waves of 7.0 mV (steroid lead: 3.5 mV) after 12 months. Children with myocardial scar tissue requiring pacemaker therapy after surgery of CHD showed no differences in sensing and pacing thresholds in comparison to children with congenital rhythm disorders. The fractally coated screw-in lead offers technical advantages concerning the subxiphoidal implantation procedure.

Conclusion: Fractally coated ventricular screw-in leads represent a feasible alternative to the common steroid eluting leads- especially in children requiring pacemaker therapy after surgery for CHD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-005-3409-9DOI Listing
October 2005

Insulin tolerance test causes hypokalaemia and can provoke cardiac arrhythmias.

Horm Res 2004 5;62(2):84-7. Epub 2004 Jul 5.

University Children's Hospital, Tübingen, Germany.

We report the observation and analysis of a new adverse event during the insulin tolerance test (ITT) and propose additional safety procedures. An 8-year-old girl with growth hormone insufficiency had a cardiac arrest due to ventricular flutter when she was tested for growth hormone deficiency by the ITT. Severe hypokalaemia (K+ 2.6 mmol/l) was observed after resuscitation. Ergometry ECG revealed catecholaminergic polymorphic ventricular tachycardia, a hereditary arrhythmogenic disease. Consecutive measurements of serum potassium during ITT in 29 short children (21 boys) with growth failure revealed a mean decrease of serum potassium by 1.1 +/- 0.4 mmol/l with the nadir at 30 min after the insulin bolus. Hypokalaemia (serum potassium < 3.5 mmol/l) occurred in all but one child; severe hypokalaemia (serum potassium < 2.9 mmol/l) was measured in every third child. This observation indicates that acute hypokalaemia which is induced by insulin and catecholamine excess occurs frequently in ITT. The case shows that the combination of acute hypokalaemia and the adrenergic counterregulation in ITT is a strong trigger of cardiac arrhythmias, which can become life-threatening if the child has an arrhythmogenic disease. Therefore, we recommend ECG monitoring during ITT to enhance the detection of cardiac arrhythmias. In addition, in the case of a comatose child during ITT the determination of the glucose and potassium level as well as adequate treatment are necessary.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000079539DOI Listing
February 2005

DDD pacemaker implantation after Fontan-type operations.

Pacing Clin Electrophysiol 2003 Jan;26(1P2):492-5

Departments of Thoracic, Cardiac, and Vascular Surgery, University Hospital, Tübingen, Langenbeckstr. 1, # 505, 55131 Mainz, Germany.

Bradyarrhythmias developing after Fontan-type operations impair the function of the univentricular heart causing fatigue, headaches, ascites, and protein-losing enteropathy (PLE). Transvenous inaccessibility, requiring epicardial implantation, accounts for the reluctance to implant a pacemaker (PM). Between 1997 and 2000, 24 patients (mean age 9.5 years, range 6 months to 19 years) with Fontan-type operations received DDD pacing systems with atrial steroid-eluting stitch-on electrodes (mean capture threshold 1.9 V/0.5 ms, range 0.4-3.5 V) and ventricular screw-in electrodes (mean capture threshold 1.7 V/0.5 ms, range 0.1-3 V). The systems were implanted at the time of conversion from atrio- to cavopulmonary connections in 5 patients, at the time of a total cavopulmonary Fontan operation in 6, and 1-50 months thereafter (mean = 18) in 13 patients. A right ventricular anatomy was present in 13 (54%) of 24 of PM recipients, versus 35% of the overall population. After a mean follow-up of 3.5 years, the PM were functioning in DDD mode in 23 of the 24 patients. Length of hospital stay in the ten patients who underwent repeat sternotomy was 5 days, without procedure related complications. In three children a repeat sternotomy was avoided by implanting the atrial electrodes during the Fontan operation. All patients improved clinically, including resolution of PLE in four patients. Bradyarrhythmias may lead to significant morbidity after Fontan-type operations. Electrophysiological evaluation is advised at follow-up. The indication for implantation of a DDD pacemaker system should be liberal. Placing atrial electrodes during the Fontan operation, especially in the presence of a right ventricular anatomy, avoids repeat sternotomy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1046/j.1460-9592.2003.00079.xDOI Listing
January 2003