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Inappropriate ICD therapy is associated with adverse outcome. Previous studies indicated that patients with a cardiac resynchronization therapy-defibrillator (CRT-D) might have a lower risk for inappropriate device activations than patients with a single (VVI) or dual chamber (DDD) ICD.All ICD recipients from a university cardiac center between 2000 - 2015 were included in this analysis. Outcome parameters were incidence of appropriate and inappropriate therapy and overall mortality.A total of 1471 patients were analyzed: 629 (43%) patients with a VVI-ICD, 486 (33%) patients with a DDD-ICD and 356 (24%) with a CRT-D device. During an average follow-up of 4.1 ± 3.6 years, CRT-D patients had the lowest risk to receive at least one inappropriate shock therapy (p 0.001). Rates of appropriate (RR (Rate Ratio) = 0.45, p = 0.019) and inappropriate shock therapy (RR = 0.38, p = 0.021) were significantly lower in CRT-D patients compared to VVI-patients. CRT-D recipients had a lower rate of appropriate shock therapy (RR = 0.323, p = 0.043) compared to DDD patients, but not of inappropriate shock therapy (p = 0.371). Kaplan Meier Analysis did not reveal a significant difference in overall survival (p = 0.396). However, after adjustment for relevant confounding factors, VVI-patients had a higher risk for overall-death (HR = 1.28, p = 0.030).CRT-D recipients have a significantly lower rate of appropriate shock therapy and a lower rate of inappropriate shock therapy. More frequent inappropriate therapies in VVI-ICD recipients may account for their higher overall mortality.

Aims Ventricular arrhythmias are common after acute myocardial infarction (AMI). Endothelin (ET) is a mediator of microvascular dysfunction and cardiac remodeling with arrhythmogenic potential. The aim of this study was to assess safety and feasibility of selective ET-A receptor blockade in ST-elevation acute coronary syndrome (STE-ACS) within a larger randomized trial. Main methods Patients with posterior-wall STE-ACS were randomly assigned to receive intravenous BQ-123 at 400 nmol/min or placebo over 60 min, starting immediately prior to primary percutaneous coronary intervention. Twenty-four hour Holter recordings were performed during hospitalization for STE-ACS and after 6–8 weeks. The predefined primary endpoint was the documentation of ventricular tachycardia and/or late potentials at follow-up. Key findings There was no significant difference in the predefined primary endpoint at 45 (33–62) days (0/16 (0%) in BQ-123 treated patients vs. 1/14 (7%) in the placebo group, p = 0.465). At 2 (1–3) days, an increase in the total number of supraventricular extrasystoles (SVES)/24 h in patients randomized to BQ-123 (45 (17–165) beats vs. 11 (5–72) beats in placebo treated patients, p = 0.025) occurred. This increase was also observed at 45 days (105 (37–216) beats vs. 11 (3–98) beats in placebo treated patients, p = 0.037). There was no significant difference regarding other rhythmologic secondary endpoints between the two groups. Significance Based on the analysis of long-term ECG data, short-term administration of BQ-123 after AMI was safe. Because of the small sample size, no firm conclusion regarding antiarrhythmic efficacy can be drawn.

Background The aim of the study was to investigate the safety and efficacy of a single, remote-magnetic catheter navigation system (MNS) for pulmonary vein isolation (PVI). Methods A total of 107 PVI procedures in 71 patients with paroxysmal (32%), persistent (38%) and longstanding-persistent (30%) atrial fibrillation (AF) were analyzed. A wide area circumferential radiofrequency ablation PVI was performed with either an 8mm MNS (first 35 procedures) or an irrigated MNS (last 36 procedures) catheter. Electrical isolation was confirmed with circular pacing/sensing using the MNS catheter and a coronary sinus catheter. Our follow-up strategy in the first year and upon symptoms thereafter was: clinical check plus 12-lead ECG (100%) and 24h-ECG recordings (76%) at 3month intervals, trans-telephonic ECG (79%) twice daily and upon symptoms (4weeks every 3months), or ECG monitoring via implanted devices (9%). Results The mean procedure time at 1st PVI was 247±61min, and mean fluoroscopy time was 44±18min. The overall complication rate was 2%. Success rates did not differ at the 1st PVI regarding catheter type ( p =0.931) but were dependent on history of AF: patients with paroxysmal AF had the highest success rates of 58% and 29% after 1 and 3years of follow-up, respectively ( p =0.0084). Conclusion PVI with a single MNS catheter is safe and is associated with short fluoroscopy exposition. Despite a rigorous follow-up strategy success rates favorably compare with recently published data on hand-held PVI. Thus, multipolar catheters or a 2nd trans-septal puncture may not be mandatory.

Background Brugada syndrome (BS) is associated with an increased risk of sudden cardiac death (SCD) caused by ventricular tachyarrhythmia. Thus, implantable cardioverter defibrillators (ICD) became the main therapeutic option in these patients. We aimed to investigate the prevalence of BS in the Eastern Alps as well as the benefit of ICD therapy in this collective. Methods During physical examination before military service, 47,606 Austrian men were screened for Brugada ECG pattern. Furthermore, we followed 4491 patients with arrhythmia during the last two decades, of which 26 patients (20 male; age at diagnosis: 43.2±11.6 years) revealed BS. Diagnosis was based on characteristic ECG either at rest (11 patients) or after provocation with Ajmaline (15 patients). Results The nationwide screening revealed one individual with Brugada ECG (prevalence of 2.10/100,000 inhabitants). Prior to diagnosis of BS, syncope and SCD survival were observed in 7 and 4 patients, respectively; the remaining 15 patients were asymptomatic. ICD were implanted in 17 patients (15 male). Three asymptomatic patients received no ICD because no tachyarrhythmia was inducible on programmed stimulation. Six asymptomatic patients without family history of sudden death refused further evaluation. Mean ICD follow-up period was 57.0±32.2 months. Two patients (11.7%) needed defibrillation therapy. Four patients (23.5%) received exclusively inappropriate shocks (three due to T-wave oversensing, one due to atrial fibrillation). Conclusions Brugada syndrome has a low prevalence in the Eastern alpine region. Patients with BS benefit from ICD implantation, but less frequently than anticipated. The problem of inappropriate ICD discharges is still of major concern.

Background . Cerebral embolization is a major cause of central nervous dysfunction after cardiopulmonary bypass. Experimental studies demonstrate that reductions in arterial carbon dioxide tension (PaCO 2 ) can reduce cerebral embolization during cardiopulmonary bypass. This study examined the effects of brief PaCO 2 manipulations on cerebral embolization in patients undergoing cardiac valve procedures. Methods . Patients were prospectively randomized to either hypocapnia (PaCO 2 = 30 to 32 mm Hg, n=30) or normocapnia (PaCO 2 = 40 to 42 mm Hg, n=31) before aortic cross-clamp removal. With removal of the aortic cross-clamp embolic signals were recorded by transcranial Doppler ultrasonography for the next 15 minutes. Results . Despite significant differences in PaCO 2 , groups did not differ statistically in total cerebral emboli counts. The mean number of embolic events was 107 ± 100 (median, 80) in the hypocapnic group and 135 ± 115 (median, 96) in the normocapnic group, respectively ( p = 0.315). Conclusions . Due to the high between-patient variability in embolization, reductions in PaCO 2 did not result in a statistically significant decrease in cerebral emboli. In contrast to experimental studies, the beneficial effect of hypocapnia on cerebral embolization could not be demonstrated in humans.