Decoding cardiac reinnervation from cardiac autonomic markers: A mathematical model approach.

BACKGROUND: Although cardiac autonomic markers (CAMs) are commonly used to assess cardiac reinnervation in heart-transplant patients, their relationship to the degree of sympathetic and vagal cardiac reinnervation is not well understood yet. To study this relationship, we applied a mathematical model of the cardiovascular system and its autonomic control. METHODS: By simulating varying levels of sympathetic and vagal efferent sinoatrial reinnervation, we analyzed the induced changes in CAMs including resting heart rate (HR), bradycardic and tachycardic HR response to Valsalva maneuver, root mean square of successive differences between normal heartbeats (RMSSD), low-frequency (LF), high-frequency (HF), and total spectral power (TSP). RESULTS: For assessment of vagal cardiac reinnervation levels >20%, resting HR (ρ = 0.99, p < 0.05), RMSSD (ρ = 0.97, p < 0.05), and TSP (ρ = 0.96, p < 0.05) may be equally suitable as HF-power (ρ = 0.97, p < 0.05). To assess sympathetic reinnervation, LF/HF ratio (ρ = 0.87, p < 0.05) and tachycardic response to Valsalva maneuver (ρ = 0.9, p < 0.05) may be more suitable than LF-power (ρ = 0.77, p < 0.05). CONCLUSIONS: Our model reports mechanistic relationships between CAMs and levels of efferent autonomic sinoatrial reinnervation. The results indicate differences in the suitability of these markers to assess vagal and sympathetic reinnervation. Although our analysis is purely conceptual, the developed model can help to gain important insights into the genesis of CAMs and their relationship to efferent sinoatrial reinnervation and, thus, provide indications for clinical study evaluation.

Impact of the first COVID-19 lockdown in Austria on laboratory and mental parameters in diabetic patients: a retrospective analysis highlighting the importance of regular medical consultations in a patient cohort.

BACKGROUND: Due to the COVID-19 pandemic, the first lockdown was implemented in Austria for almost 7 weeks. In contrast to many other countries, medical consultations were permitted, either by telemedicine or at doctors' offices. Nevertheless, restrictions related to this lockdown could possibly cause an increased risk of deterioration in health, especially in diabetes. This study aimed to assess the impact of Austria's first lockdown on laboratory and mental parameters in a type-2 diabetes mellitus cohort. METHODS: Overall 347 mainly elderly patients with type-2 diabetes (56% male; aged 63.7±10.1 years) were included in this retrospective practitioner-based analysis. Laboratory as well as mental parameters were compared from before and after the lockdown. RESULTS: The lockdown showed no significant effect on HbA1c levels. On the other hand, total cholesterol (P<0.001) and LDL cholesterol (P<0.001) levels improved significantly, whereas body weight (P<0.01) and mental well-being based on the EQ-5D-3L questionnaire (P<0.01) increased significantly in terms of worsening. CONCLUSIONS: Lack of movement and staying at home resulted in a significant weight gain and worsening of mental well-being in type-2 diabetes during the first lockdown in Austria. Thanks to regular medical consultations, laboratory parameters remained stable or even improved. Thus, routine health check-ups in mainly elderly type 2 diabetic patients are essential to minimize the deterioration of health conditions during lockdowns.

Long-term physical activity modulates adipsin and ANGPTL4 serum levels, a potential link to exercise-induced metabolic changes.

BACKGROUND: Within the presented prospective study, we aimed to illuminate the effect of long-term physical exercise on serum levels of adipsin (complement factor D) and angiopoietin-like 4 (ANGPTL4). Although past studies already outlined the effects of acute exercise, our trial design aimed to depict the development under long-term physical activity conditions. METHODS: Ninety-eight participants were included in the study and were asked to perform eight months of moderate physical activity for at least 150 minutes/week and/or vigorous-intensity exercise for at least 75 minutes/week. According to initial performance and performance gain throughout the study period, four groups were formed and subsequently compared. Blood sampling for the determination of routine laboratory parameters was done at baseline, after 2, 6, and 8 months. Additionally, adipsin and ANGPTL4 serum levels were concurrently quantified using commercially available ELISA kits. RESULTS: The study cohort consisted of 61.2% male participants with an average age of 49.3±6.7 years. Adipsin and ANGPTL4 were found to be strongly increased by long-term physical exercise. Participants displaying a performance gain of >2.9% throughout the study showed significantly increased serum levels of both biomarkers. CONCLUSIONS: Serum levels of adipsin and ANGPTL4 were closely tied to the individual performance gain of the participating probands. An association of adipsin levels, initial performance, and serum triglycerides was found at baseline. Interestingly, this interrelationship was not detectable after eight months of physical training. This finding might indicate adipsin's involvement in linking triglyceride-balance to individual performance and energy demands in a homeostatic state.

Usage of the wearable cardioverter-defibrillator during pregnancy.

Background: Pregnancy can trigger or aggravate the risk for life-threating arrhythmias in cardiac diseases. Pregnancy is associated with reluctance for implantable cardioverter-defibrillators (ICD) due to concerns about radiation. Thus, the wearable cardioverter-defibrillator (WCD) might be an option during pregnancy. Aim of the study was to collect experiences about the use of WCD in pregnancy. Methods and results: This study retrospectively included eight women who received a WCD during pregnancy. They suffered from ventricular tachycardia (VT) without known cardiac disease (n = 3), Brugada syndrome (n = 1), hypertrophic cardiomyopathy (n = 1), dilated cardiomyopathy (n = 1), non-compaction (n = 1), and survived sudden cardiac arrest during a preceding pregnancy (n = 1). WCD usage was started between 13 and 28 weeks of gestation. WCD wearing period ranged from 3 days to 30.9 weeks, WCD wearing time ranged from 13.0 to 23.7 h per day. Two women (25%) abandoned WCD already during pregnancy. Neither appropriate nor inappropriate WCD shocks were recorded. Antiarrhythmic management included beta-blockers (n = 5) and flecainide (n = 2). After delivery, ICD were implanted (n = 4), refused (n = 2) and estimated not necessary after successful catheter ablation (n = 2). Conclusion: Uneventful pregnancy is possible in women at risk for sudden cardiac death by interdisciplinary monitoring and diligent pharmacotherapy protected by the WCD. Since no WCD shocks were recorded, the effectiveness of WCD during pregnancy is still unclear. However, arrhythmia detection by WCD was very good despite the changed anatomy in pregnancy. Nevertheless, further studies are necessary to assess effectiveness of WCD in pregnant women. Furthermore, efforts should be made to increase the wearing adherence of WCD during pregnancy.

Twiddler's syndrome after implantation of baroreflex activation therapy: a case report.

BACKGROUND: Twiddler's syndrome is a rare complication after implantation of cardiac pacemakers or cardioverter-defibrillators that usually occurs within the first year after the procedure. However, it has not yet been described following implantation of baroreflex activation therapy (BAT). CASE SUMMARY: A 61-year-old female patient was referred to the cardiology outpatient clinic due to uncontrolled arterial hypertension despite maximal doses of several established drugs. Therefore, right-sided BAT implantation was successfully performed in February 2017 with good clinical response. Because of sustained neck pain at the site of stimulator, surgical revision was performed in November 2019 including a switch of the lead to the contralateral position. Approximately 1 month later, Twiddler's syndrome was identified on the basis of recurrent pain at the generator site necessitating pocket-revision, however, the lead was only untwisted but not replaced. A few weeks afterwards, unfortunately, lead revision was indispensable due to lead fracture. DISCUSSION: This case presents the uncommon phenomenon of Twiddler's syndrome after BAT implantation. In addition, the commonly twisted lead should always be replaced as well during surgical pocket-revision in order to ensure proper long-term function.

Pacemaker lead-associated tricuspid regurgitation in patients with or without pre-existing right ventricular dilatation.

BACKGROUND: Transcatheter tricuspid valve intervention became an option for pacemaker lead-associated tricuspid regurgitation. This study investigated the progression of tricuspid regurgitation (TR) in patients with or without pre-existing right ventricular dilatation (RVD) undergoing pacemaker implantation. METHODS: Patients were included if they had implantation of transtricuspid pacemaker lead and completed echocardiography before and after implantation. The cohort was divided in patients with and without RVD (cut-off basal RV diameter ≥ 42 mm). TR was graded in none/mild, moderate, and severe. Worsening of one grade was defined as progression. Survival analyses were plotted for 10 years. RESULTS: In total, 990 patients were analyzed (24.5% with RVD). Progression of TR occurred in 46.1% of patients with RVD and in 25.6% of patients without RVD (P < 0.001). Predictors for TR progression were RV dilatation (OR 2.04; 95% CI 1.27-3.29; P = 0.003), pre-existing TR (OR 4.30; 95% CI 2.51-7.38; P < 0.001), female sex (OR 1.68; 95% CI 1.16-2.43; P = 0.006), single RV lead (OR 1.67; 95% CI 1.09-2.56; P = 0.018), mitral regurgitation (OR 2.08; 95% CI 1.42-3.05; P < 0.001), and enlarged left atrium (OR 1.98; 95% CI 1.07-3.67; P = 0.03). Survival-predictors were pacemaker lead-associated TR (HR 1.38; 95% CI 1.04-1.84; P = 0.028), mitral regurgitation (HR 1.34; 95% CI 1.02-1.77; P = 0.034), heart failure (HR 1.75; 95% CI 1.31-2.33; P < 0.001), kidney disease (HR 1.62; 95% CI 1.25-2.11; P < 0.001), and age ≥ 80 years (HR 2.84; 95% CI 2.17-3.71; P < 0.001). CONCLUSIONS: Patients with RVD receiving pacemaker suffered from increased TR progression, leading to decreased survival.

Conduction disturbances following surgical aortic valve replacement with a rapid-deployment bioprosthesis.

BACKGROUND: The implantation of rapid-deployment aortic valves may interfere with the conduction system of the heart. This study evaluates the occurrence and predictive factors of conduction anomalies in patients undergoing surgical aortic valve replacement (SAVR) with a rapid-deployment balloon-expandable bioprosthesis in a single-center, real-world experience. METHODS: Between May 2010 and April 2019, 700 consecutive patients were included in a prospective, ongoing database with a longitudinal follow-up preoperatively, at discharge, and at 3 months, 1 year, 3 years, and 5 years postoperatively. Thirty-seven patients (5.3%) had a permanent pacemaker at baseline and were excluded from further analysis, leaving 663 patients for analysis. Assessment of conduction anomalies was performed by electrocardiography (ECG) monitoring and repeated 12-lead ECG during the hospital stay and at postoperative follow-ups. RESULTS: Preoperatively, 126 patients (19.0%) presented with different conduction disturbances. New permanent pacemaker implantation (PPI) occurred in 61 patients during the first 14 days (cumulative incidence, 9.4%). The indication for PPI was complete atrioventricular block in 47 cases (77%). Preoperative conduction anomalies, such as right bundle branch block, as well as operative characteristics (concomitant procedures) were found to be independent predictors for new PPI. One-year survival was 98% in patients with new early PPI and 96% in those without new early PPI (P = .60). CONCLUSIONS: The PPI rate was in the range of previous reports for rapid-deployment prostheses. PPI did not have a significant influence on short- to intermediate-term survival. Case selection with exclusion of patients presenting with baseline conduction disturbances may decrease the rate of new PPIs after SAVR with rapid-deployment balloon-expandable bioprostheses.

Recommendations on the utilization of telemedicine in cardiology.

The enormous progress made in recent years in the field of information and communication technology and also in sensor and computer technology has affected numerous fields of medicine and is capable of inducing even radical changes in diagnostic and therapeutic processes. This is particularly true for cardiology, where, for example, telemetric monitoring of cardiac and circulatory functions has been in use for many years. Nevertheless, broad application of newer telemedical processes has not yet been achieved to the extent one would expect from the encouraging results of numerous clinical studies in this field and the state of the art of the underlying technology. In the present paper, the Working Group on Rhythmology of the Austrian Cardiological Society aims to provoke a critical discussion of the digital change in cardiology and to make recommendations for the implementation of those telemedical processes that have been shown to exert positive effects on a wide variety of medical and economic parameters. The greatest benefit of telecardiological applications is certainly to be found in the long-term care of patients with chronic cardiovascular diseases. Accordingly, follow-up care of patients with cardiological rhythm implants, management of chronic heart failure and secondary prevention following an acute cardiac event during rehabilitation are currently the most important fields of application. Telemedicine is intended to enable high-quality and cost-efficient care for an increasing number of patients, whose care poses one of the greatest challenges to our healthcare system. Not least of all, telemedicine should make a decisive contribution to improving the quality of life of this segment of the population by favorably influencing mortality, morbidity and hospitalization as well as the patient's contribution to treatment.

Sex Differences and Long-Term Outcome in Patients With Pacemakers.

Introduction: Evidence of sex-related differences in patients with pacemakers regarding comorbidities is insufficiently investigated. The aim of this study was to determine the relationship of cardiovascular comorbidities and sex category with properties of pacemaker implantation, pacemaker follow-up, and long-term survival. Methods: This retrospective, single-center cohort study consisted of 6,362 pacemaker-patients (39.7% female) enrolled between May 2000 and April 2015. Functional pacemaker parameters were registered at regular pacemaker controls. Survival status and cause of death were analyzed in relation to comorbidities, implanted pacing devices, and echocardiography. Survival analyses were plotted for a 10-year follow-up. Results: Patients with hypertension or hyperlipidemia had higher rates of implantations due to sick sinus syndrome (28.6 vs. 25.5% without hypertension, P < 0.001; 30.7 vs. 25.7% without hyperlipidemia, P < 0.001), while endocarditis was associated with higher rates of implantations due to AV block (46.7 vs. 33.4%, P < 0.001). Patients with valvular heart disease had higher rates of pacemaker implantation due to bradycardic atrial fibrillation (24.9 vs. 21.0% without valvular heart disease, P < 0.001). Ventricular pacing threshold increased in both sexes during the follow-up and was higher in women in the final follow-up (0.94 vs. 0.91 V in men, P = 0.002). During the 10-years follow-up, 6.1% of women and 8.6% of men underwent lead replacement (P = 0.054). Device and lead replacement rates were increased if the comorbidities coronary artery disease, heart failure, hypertension, hyperlipidemia, valvular heart disease, previous stroke/TIA, atrial arrhythmias, chronic kidney disease, or endocarditis were present. Diabetes and previous CABG increase the rates of device replacement, but not the rate of lead replacement. Severe tricuspid regurgitation after implantation of pacemaker was present in more men than women (14.4 vs. 6.1%, P < 0.001). In a multivariate COX regression, the following variables were associated with independent decrease of 10-year survival: hypertension (HR 1.34, 95% CI 1.09-1.64), chronic kidney disease (HR 1.83, 95% CI 1.53-2.19), tricuspid regurgitation after pacemaker implantation (HR 1.48, 95% CI 1.26-1.74). Survival was independently increased in female sex (HR 0.83, 95% CI 0.70-0.99) and hyperlipidemia (HR 0.81, 95% CI 0.67-0.97). Conclusions: Cardiovascular comorbidities influenced significantly pacemaker implantations and long-term outcome. Trial Registration: ClinicalTrials.gov Unique identifier: NCT03388281.

State-of-the-art consensus on non-transvenous implantable cardioverter-defibrillator therapy.

Within the last decade, implantable cardioverter-defibrillator (ICD) systems with non-transvenous leads were developed in order to minimize complications related to the cardiovascular position of transvenous ICD leads. This national expert consensus gives an overview of potential indications for the implantation of non-transvenous ICD systems, and provides specific recommendations for implantation, follow-up, and complication management in patients with subcutaneous ICD. Regarding particular issues like the necessity for shock efficacy testing, or the clinical outcome as compared to transvenous ICD, randomized data are expected in the near future.

Regular Training Increases sTWEAK and Its Decoy Receptor sCD163-Does Training Trigger the sTWEAK/sCD163-Axis to Induce an Anti-Inflammatory Effect?

BACKGROUND: Low levels of soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) were reported in patients with coronary artery disease, heart failure, chronic kidney disease and diabetes mellitus. Soluble cluster differentiation 163 (sCD163) serum levels are related to M2 macrophages, having anti-inflammatory attributes. As sport is well-known for its anti-inflammatory and cardioprotective effects we aimed to investigate the influence of eight months of physical activity on serum sCD163 and sTWEAK levels. METHODS: In total, 109 subjects with at least one cardiovascular risk factor were asked to perform endurance training within the calculated training pulse for eight months. Overall, 98 finished the study. The performance gain was measured/quantified by bicycle stress tests at the beginning and end of the observation period. The cohort was divided into four groups, dependent on their baseline performance and performance gain. sCD163 and sTWEAK were measured at baseline and after two, six and eight months by ELISA. RESULTS: Those participants who had a performance gain of ≤2.9% (mean gain 12%) within eight months showed a significant increase in sTWEAK (group 2: from 133 to 200 pg/mL, p = 0.002 and group 4: from 166 to 212 pg/mL, p = 0.031) and sCD163 levels (group 2: from 255 to 348 ng/mL, p = 0.035 and group 4: from 247 to 288 ng/mL, p = 0.025) in contrast to subjects without performance gain (sTWEAK: group 1: from 161 to 177 pg/mL, p = 0.953 and group 3: from 153 to 176 pg/mL, p = 0.744; sCD163: group 1: from 289 to 256 ng/mL, p = 0.374 and group 4: from 291 to 271 ng/mL, p = 0.913). Baseline sCD163 correlated with erythrocyte count, hematocrit, ASAT and lipoprotein a, the presence of hypertension and a BMI > 30 kg/m2. CONCLUSION: Regular physical activity leads to a significant increase in sCD163 and sTWEAK levels of up to 37% and 50%, respectively. It is well-known that physical activity prevents or retards the onset and genesis of chronic inflammatory disease. One possible way of how training evolves its beneficial effect might be by modifying the inflammation status using the sTWEAK-sCD163 axis. Brief Summary: Regular physical activity leads to a significant increase in sTWEAK and sCD163 levels. Both factors are diminished in patients with chronic (inflammation-based) diseases, such as coronary artery disease, heart failure, pulmonary artery hypertension, chronic kidney disease and diabetes mellitus. It seems that the amounts of soluble TWEAK and CD163 are essential for a healthy balance and modulation between pro- and anti-inflammatory processes, and regular physical training could use the sCD163-sTWEAK axis to unfold its beneficial effect.

Paper-based training diaries for monitoring of performance progress due to long-term physical activity.

INTRODUCTION: Training diaries are a common tool for training monitoring; however, their correlation with an effective performance gain is unclear. OBJECTIVES: The aim of this prospective study was to investigate whether monitoring of training by paper­based training diaries reflects the training progress measured by a bicycle stress test in hobby athletes. PATIENTS AND METHODS: Out of 109 hobby athletes who were instructed to work out for 8 months with a calculated training pulse, 98 participants completed the study. Training workload (intensity and time) was recorded with special training diaries. To assess the objective performance gain or change, the bicycle stress test was performed at baseline and at the end of the study. Surrogate parameters associated with increased physical activity were also recorded. RESULTS: Participants who had a performance gain of at least 3% (mean gain of about 12%) in the bicycle stress test worked out between 547 and 576 min/mo with moderate intensity, and between 14 and 187 min/mo with high intensity. Neither moderate- nor high-intensity training correlated with the performance gain. CONCLUSIONS: Paper-based training diaries might serve as an additional tool in the monitoring of training progress. However, because of the discrepancy between reported training loads and objectively measured training progress, they are not suitable to replace a standard bicycle stress test for an exact determination of performance gain in hobby athletes. New devices, such as fitness trackers or watches, may present better alternatives in the future.

Safety and efficiency of low-field magnetic resonance imaging in patients with cardiac rhythm management devices.

PURPOSE: Low-field magnetic resonance imaging (MRI), i.e. MRI with a static magnetic field strength <0.5 T, has been reported to be safe in patients with pacemakers, however there are no data about the safety of low-field MRI in patients with implantable cardioverter defibrillators (ICD) and/or cardiac resynchronization therapy (CRT). We aimed to investigate the safety and diagnostic efficiency of routine low-field MRI in patients with different devices for cardiac rhythm management (i.e. pacemakers and ICD, including devices with CRT). METHOD: MRI scans of 446 regions of interest were evaluated with field strength of 0.2 T in 338 patients (62% male; age at MRI scan 76.1 ± 9.2 years; time since device implantation 4.1 ± 3.2 years) with cardiac rhythm management devices (298 pacemakers, 25 ICD, 8 CRT-ICD, and 7 CRT pacemakers). This analysis included 62 pacemaker-dependent patients (18.3%), 52 patients with 1.5-Tesla-MR conditional pacemakers (15.4%) and 13 patients with abandoned leads (3.9%). RESULTS: Except for one examination, which was interrupted because of recurrent severe nausea, all MRI scans could be analyzed efficiently. No induction of arrhythmia or inhibition of pacemaker function occurred. Compared to the device interrogation before MRI, there were no significant changes in battery voltage, pacing capture threshold, sensing of intrinsic ECG, lead impedance, as well as shock impedance in ICD devices after completed examination. CONCLUSIONS: Low-field MRI examinations (0.2 T) were efficient and safe regarding clinical and technical complications in patients with devices for cardiac rhythm management, even in case of pacemaker-dependency or the presence of abandoned leads.

Influence of a fully magnetically levitated left ventricular assist device on functional interrogation of implantable cardioverter defibrillators.

BACKGROUND: Electromagnetic interference between left ventricular assist devices (LVAD) and the telemetry wand of implantable cardioverter-defibrillators (ICD) with impairment of ICD interrogation has previously been described in HVAD and HeartMate II devices. This is the first study showing the potential influence of the LVAD model HeartMate 3 (with the unique feature of fully magnetically levitated rotor with consistent wide blood-flow gaps) on functional interrogation of different ICD models. METHODS AND RESULTS: Among 51 patients treated with a HeartMate 3 LVAD, 34 patients (66.7%) already had an ICD implanted prior to LVAD therapy. In this cohort, impairment of ICD interrogation was observed in five patients (14.7%) with five different device models. In patients with Biotronik ICD, stretching of the ipsilateral arm to increase the distance between both devices >10 cm was sufficient in one patients, whereas surgical contralateral repositioning was necessary in two patients; in one further patient no action could be taken, as he died early from embolic stroke. In the only patient with a MicroPort ICD, this issue was resolved by using a wireless telemetry. The distances between both devices showed no statistical significant correlation with an impaired interrogation, neither in the overall collective nor within the groups with the same manufacturer. CONCLUSIONS: In patients with impaired ICD interrogation caused by electromagnetic interference between a HeartMate 3 LVAD and the ICD, the actions mentioned above have to be taken, to resolve this technical issue. Especially, a sufficient distance of at least 10 cm between both devices was crucial for avoiding this problem.

The subcutaneous implantable cardioverter-defibrillator: A tertiary center experience.

BACKGROUND: The aim of the study was to evaluate subcutaneous implantable cardioverter-defibrillator (S-ICD) patients with regard to underlying etiology, peri-procedural outcome, appropriate/inappropriate shocks, and complications during follow-up. METHODS: All patients who underwent S-ICD implantation from February 2013 to March 2017 at an academic hospital in Vienna were included. Medical records were examined and follow-up interrogations of devices were conducted. RESULTS: A total of 79 S-ICD patients (58.2% males) with a mean age of 44.5 ± 17.2 years were followed for a mean duration of 12.8 ± 13.7 months. A majority of patients (58.2%) had S-ICD for primary prevention of sudden cardiac death. The most common of the 16 underlying etiologies were ischemic cardiomyopathy, non-ischemic cardiomyopathy, and idiopathic ventricular fibrillation. The lead was implanted to the left sternal border in 96.2% of cases, between muscular layers in 72.2%. Mean implant time was 45 min, 3 patients were induced, and all patients except one were programmed to two zones. Six (7.6%) patients experienced at least one appropriate therapy for ventricular arrhythmias and the time to first event ranged from 1 to 52 months. Seven patients experienced inappropriate shocks due to T-wave oversensing, atrial tachycardia with rapid atrioventricular conduction, external electromagnetic interference, and/or baseline oversensing due to lead movement. Four patients underwent revision for lead repositioning (n = 1), loose device suture (n = 1), and infection (n = 2). CONCLUSIONS: While S-ICDs are a feasible and effective treatment, issues remain with inappropriate shock and infection.

Prevalence of early repolarization syndrome and long-term clinical outcome in patients with the diagnosis of idiopathic ventricular fibrillation.

Idiopathic ventricular fibrillation (IVF) is diagnosed in up to 14% of sudden cardiac death (SCD) survivors. Early repolarization syndrome (ERS) in patients with ventricular tachyarrhythmia is characterized by an elevated J-point in inferior and/or antero-lateral leads. Our objectives were to determine the prevalence of ERS in IVF patients, and to evaluate potential differences in clinical outcome. Out of 3,552 implantable cardioverter defibrillator (ICD) carriers, 758 SCD survivors were retrospectively identified from the databases of the Medical Universities of Vienna and Innsbruck within the last three decades. Early repolarization pattern (ERP) was classified either as "notching" or "slurring". Endpoints were defined as appropriate ICD therapies for ventricular tachyarrhythmia, either anti-tachycardia pacing or shock, and all-cause mortality. After exclusion of recognized reasons for SCD, 50 patients were assigned to the diagnosis of IVF (6.6%). An ERP was identified in 10 patients, most of them with notching (n = 8). After a mean follow-up of 11.2 ± 6.7 years (539.3 patient years), appropriate ICD therapies were found in 50% of ERS and 43% of IVF patients without ERP (p = 0.732). In ERS patients, all ICD therapies were found in patients with notching pattern. Similarly, incidence of inappropriate ICD therapies, and all-cause mortality was comparable (30% vs. 23%, p = 0.707; 10% vs. 5%, p = 0.496, respectively). In 758 SCD survivors, we found a low prevalence of IVF and ERS. Similar event rates were reported concerning all-cause mortality and ICD therapies for ventricular tachyarrhythmia after long-term follow-up in this cohort.

Specific indications and clinical outcome in patients with subcutaneous implantable cardioverter-defibrillator (ICD) - A nationwide multicentre registry.

BACKGROUND: Subcutaneous implantable cardioverter-defibrillators (S-ICD) are an innovative and less invasive alternative to transvenous ICD (TV-ICD) in selected patients. We aimed to investigate the underlying diseases and the specific indications for implanting S-ICD in clinical practice, as well as the prevalence of shock delivery and complications. METHODS AND RESULTS: From December 2012, data of 236 patients (30,5% female; age 48,6±16,8years) were gathered from 12 centres in Austria. Follow-up data over a period of 1,7±1,1years were available for 231 patients (in total 359,2 patient-years). Predominant underlying diseases were ischemic cardiomyopathy (iCMP; 32,0%), idiopathic ventricular fibrillation (22,6%) and dilated cardiomyopathy (dCMP; 17,3%). The most frequent indications for implantation were sudden cardiac death survival (27,4%), primary prevention for iCMP (23,9%) and for dCMP (12,8%), and previous explantation of TV-ICD (12,4%). Appropriate shocks were documented in 16 patients (6,9%), iCMP being the predominant underlying disease. Arrhythmia conversion was successful in all patients, efficacy of the first shock was 96%. Inappropriate shock rate was 5,2%, predominantly caused by oversensing of T wave or artefacts. A device upgrade to an ICD system with pacing function was necessary in <1%. Clinical complications needing surgical revision occurred in 8 patients (3,5%). CONCLUSIONS: S-ICD were mostly implanted for primary prevention, one fourth of our cases were sudden death survivors. Clinical and functional complication rate was relatively low. In conclusion, S-ICD is a safe and efficient alternative in a larger population of ICD candidates, when no cardiac pacing is needed. EC-number: C-136-17.

Health-related quality of life changes in patients undergoing repeated catheter ablation for atrial fibrillation.

OBJECTIVE: Pulmonary vein isolation (PVI) for paroxysmal or non-paroxysmal atrial fibrillation (AF) should increase health-related quality of life (QOL). DESIGN: Retrospective cohort study of consecutive patients scheduled for PVI. SETTING: University Medical Center. MAIN OUTCOME MEASURES: QOL was assessed using the physical (PCS) and mental (MCS) component summary scores from the SF-12v2 in patients undergoing PVI (mean 50, range 0-100, with higher scores indicating greater QOL). SF-12v2 was obtained at initial presentation (3-months) before PVI and after PVI at the end of follow-up (mean 1.7 ± 1.4 years) which included: (1) Clinical status, ECG, and 24-h ECG every 3 months, (2) trans-telephonic ECGs for 4 weeks every 3 months, or (3) continuous ECG via implanted devices. A recurrence was any atrial arrhythmia >30 s. RESULTS: Out of 229 patients (73% males; 58 ± 11 years), 72% returned SF-12v2 regarding 187 PVI procedures: 56% for 1st PVI, 48% for 2nd PVI, 71% for 3rd PVI, and 44% for 4th PVI. The mean difference between before and after PVI was 10 for PCS and 9 for MCS. History of paroxysmal or non-paroxysmal AF did not influence QOL (p = 0.724). Patients with an estimated PCS improvement ≥ 10 or an estimated MCS improvement ≥ 9 had the best outcome after repeated PVI. Success rates were 72 or 82% after 1 year compared to 20 and 22% in patients not achieving this improvement, respectively (p < 0.0001). CONCLUSION: Improvement in QOL correlates with success of AF ablation after single and repeated PVI. Assessment of QOL pre- and post-PVI can complement ECG techniques for PVI success monitoring.

Selection for atrial fibrillation ablation: Importance of diastolic function grading.

BACKGROUND: Pulmonary vein isolation (PVI) has become an accepted therapy for patients with atrial fibrillation (AF) and the indications have widened to include non-paroxysmal AF-patients. Maintenance of sinus rhythm after PVI can be adversely affected by clinical or echocardiographic parameters, which should be clearly identified. METHODS AND RESULTS: After baseline clinical and echocardiographic evaluations, PVI was performed in patients with paroxysmal or non-paroxysmal AF. The follow-up strategy after PVI included: (1) clinical follow up, 12-lead electrocardiography (ECG) and 24-h ECG every 3 months, (2) trans-telephonic ECGs twice daily and when symptomatic (over 4 weeks) every 3 months, or (3) continuous monitoring via implanted devices. A recurrence was an atrial arrhythmia lasting >30s. All 340 PVI procedures of 229 patients were analyzed. On average, 1.5 PVI procedures per patient (range, 1-6 PVI) were performed. The mean age was 58±11 years (73% male) with 109 paroxysmal and 120 non-paroxysmal AF cases. Clinical follow-up with 12-lead ECGs, 24-h ECGs, trans-telephonic ECGs, and implanted devices was complete in 100%, 63%, 51%, and 16% of cases, respectively. The overall one-year recurrence rate of 59% (range, 24-82%) was dependent on grades of diastolic function (normal - dysfunction grade III) in a multivariable analysis model. Patients with normal diastolic function had the lowest recurrence rates of 24% and 49% after 1 and 3 years of follow-up, respectively (p<0.0001). CONCLUSION: Diastolic function could serve as a simple summary predictor for AF recurrence, and would facilitate clinical decision-making in AF treatment.