Rate control drugs differ in the prevention of progression of atrial fibrillation.

AIMS: We hypothesize that in patients with paroxysmal atrial fibrillation (AF), verapamil is associated with lower AF progression compared to beta blockers or no rate control. METHODS AND RESULTS: In this pre-specified post hoc analysis of the RACE 4 randomized trial, the effect of rate control medication on AF progression in paroxysmal AF was analysed. Patients using Vaughan-Williams Class I or III antiarrhythmic drugs were excluded. The primary outcome was a composite of first electrical cardioversion (ECV), chemical cardioversion (CCV), or atrial ablation. Event rates are displayed using Kaplan-Meier curves and multivariable Cox regression analyses are used to adjust for baseline differences. Out of 666 patients with paroxysmal AF, 47 used verapamil, 383 used beta blockers, and 236 did not use rate control drugs. The verapamil group was significantly younger than the beta blocker group and contained more men than the no rate control group. Over a mean follow-up of 37 months, the primary outcome occurred in 17% in the verapamil group, 33% in the beta blocker group, and 33% in the no rate control group (P = 0.038). After adjusting for baseline characteristics, patients using verapamil have a significantly lower chance of receiving ECV, CCV, or atrial ablation compared to patients using beta blockers [hazard ratio (HR) 0.40, 95% confidence interval (CI) 0.19-0.83] and no rate control (HR 0.64, 95% CI 0.44-0.93). CONCLUSION: In patients with newly diagnosed paroxysmal AF, verapamil was associated with less AF progression, as compared to beta blockers and no rate control.

Development and external validation of prediction models to predict implantable cardioverter-defibrillator efficacy in primary prevention of sudden cardiac death.

AIMS: This study was performed to develop and externally validate prediction models for appropriate implantable cardioverter-defibrillator (ICD) shock and mortality to identify subgroups with insufficient benefit from ICD implantation. METHODS AND RESULTS: We recruited patients scheduled for primary prevention ICD implantation and reduced left ventricular function. Bootstrapping-based Cox proportional hazards and Fine and Gray competing risk models with likely candidate predictors were developed for all-cause mortality and appropriate ICD shock, respectively. Between 2014 and 2018, we included 1441 consecutive patients in the development and 1450 patients in the validation cohort. During a median follow-up of 2.4 (IQR 2.1-2.8) years, 109 (7.6%) patients received appropriate ICD shock and 193 (13.4%) died in the development cohort. During a median follow-up of 2.7 (IQR 2.0-3.4) years, 105 (7.2%) received appropriate ICD shock and 223 (15.4%) died in the validation cohort. Selected predictors of appropriate ICD shock were gender, NSVT, ACE/ARB use, atrial fibrillation history, Aldosterone-antagonist use, Digoxin use, eGFR, (N)OAC use, and peripheral vascular disease. Selected predictors of all-cause mortality were age, diuretic use, sodium, NT-pro-BNP, and ACE/ARB use. C-statistic was 0.61 and 0.60 at respectively internal and external validation for appropriate ICD shock and 0.74 at both internal and external validation for mortality. CONCLUSION: Although this cohort study was specifically designed to develop prediction models, risk stratification still remains challenging and no large group with insufficient benefit of ICD implantation was found. However, the prediction models have some clinical utility as we present several scenarios where ICD implantation might be postponed.

Nurse-led vs. usual-care for atrial fibrillation.

BACKGROUND: Nurse-led integrated care is expected to improve outcome of patients with atrial fibrillation compared with usual-care provided by a medical specialist. METHODS AND RESULTS: We randomized 1375 patients with atrial fibrillation (64 ± 10 years, 44% women, 57% had CHA2DS2-VASc ≥ 2) to receive nurse-led care or usual-care. Nurse-led care was provided by specialized nurses using a decision-support tool, in consultation with the cardiologist. The primary endpoint was a composite of cardiovascular death and cardiovascular hospital admissions. Of 671 nurse-led care patients, 543 (81%) received anticoagulation in full accordance with the guidelines against 559 of 683 (82%) usual-care patients. The cumulative adherence to guidelines-based recommendations was 61% under nurse-led care and 26% under usual-care. Over 37 months of follow-up, the primary endpoint occurred in 164 of 671 patients (9.7% per year) under nurse-led care and in 192 of 683 patients (11.6% per year) under usual-care [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.69 to 1.04, P = 0.12]. There were 124 vs. 161 hospitalizations for arrhythmia events (7.0% and 9.4% per year), and 14 vs. 22 for heart failure (0.7% and 1.1% per year), respectively. Results were not consistent in a pre-specified subgroup analysis by centre experience, with a HR of 0.52 (95% CI 0.37-to 0.71) in four experienced centres and of 1.24 (95% CI 0.94-1.63) in four less experienced centres (P for interaction <0.001). CONCLUSION: Our trial failed to show that nurse-led care was superior to usual-care. The data suggest that nurse-led care by an experienced team could be clinically beneficial (ClinicalTrials.gov NCT01740037). TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT01740037).

Permanent cardiac pacing in children: choosing the optimal pacing site: a multicenter study.

BACKGROUND: We evaluated the effects of the site of ventricular pacing on left ventricular (LV) synchrony and function in children requiring permanent pacing. METHODS AND RESULTS: One hundred seventy-eight children (aged <18 years) from 21 centers with atrioventricular block and a structurally normal heart undergoing permanent pacing were studied cross-sectionally. Median age at evaluation was 11.2 (interquartile range, 6.3-15.0) years. Median pacing duration was 5.4 (interquartile range, 3.1-8.8) years. Pacing sites were the free wall of the right ventricular (RV) outflow tract (n=8), lateral RV (n=44), RV apex (n=61), RV septum (n=29), LV apex (n=12), LV midlateral wall (n=17), and LV base (n=7). LV synchrony, pump function, and contraction efficiency were significantly affected by pacing site and were superior in children paced at the LV apex/LV midlateral wall. LV dyssynchrony correlated inversely with LV ejection fraction (R=0.80, P=0.031). Pacing from the RV outflow tract/lateral RV predicted significantly decreased LV function (LV ejection fraction <45%; odds ratio, 10.72; confidence interval, 2.07-55.60; P=0.005), whereas LV apex/LV midlateral wall pacing was associated with preserved LV function (LV ejection fraction ≥55%; odds ratio, 8.26; confidence interval, 1.46-47.62; P=0.018). Presence of maternal autoantibodies, gender, age at implantation, duration of pacing, DDD mode, and QRS duration had no significant impact on LV ejection fraction. CONCLUSIONS: The site of ventricular pacing has a major impact on LV mechanical synchrony, efficiency, and pump function in children who require lifelong pacing. Of the sites studied, LV apex/LV midlateral wall pacing has the greatest potential to prevent pacing-induced reduction of cardiac pump function.

Previous Exercise Levels and Outcome in Patients with New Atrial Fibrillation: 'Past Achievements Do Not Predict the Future'.

INTRODUCTION: Long-term endurance exercise is suspect to elevate the risk of atrial fibrillation (AF),but little is known about cardiovascular outcome and disease progression in this subgroup of AF patients. We investigated whether previous exercise level determines cardiovascular outcome. METHODS: In this post hoc analysis of the RACE 4 randomized trial, we analyzed all patients with a completed questionnaire on sports participation. Three subgroups were made based on lifetime sports hours up to randomization and previous compliance to the international physical activity guidelines. High lifetime hours of high dynamic activity patients were defined as more than 150 min/week of high intense physical exercise. The primary endpoint was a composite of cardiovascular death and hospital admissions. RESULTS: A total of 879 patients were analyzed, divided in 203 high lifetime hours of high dynamic activity -, 192 high lifetime hours of activity- and 484 low lifetime hours of activity patients. Over a mean follow up of 36 months (±14), the primary endpoint occurred in 61 out of 203 (30%) high lifetime hours of high dynamic activity -, 53 out of 192 (27%) high lifetime hours of activity- and 135 out of 484 low lifetime hours of activity patients (28%) (p = 0.74). During follow up 42 high lifetime hours of high dynamic activity- (35%), 43 high lifetime hours of activity- (32%) and 104 low lifetime hours of activity patients (34%) with paroxysmal AF received electrical or chemical cardioversion or atrial ablation (p = 0.90). CONCLUSIONS: In patients included in the RACE 4, there appears to be no relation between previous activity levels and cardiovascular outcome and the need for electrical or chemical cardioversion or atrial ablation. Cardiovascular outcome was driven by AF related arrhythmic events.

Predictive value of the PRAETORIAN score for defibrillation test success in patients with subcutaneous ICD: A subanalysis of the PRAETORIAN-DFT trial.

BACKGROUND: The PRAETORIAN score estimates the risk of failure of subcutaneous implantable cardioverter-defibrillator (S-ICD) therapy by using generator and lead positioning on bidirectional chest radiographs. The PRospective randomized compArative trial of subcutanEous implanTable cardiOverter-defibrillatoR ImplANtation with and without DeFibrillation Testing (PRAETORIAN-DFT) investigates whether PRAETORIAN score calculation is noninferior to defibrillation testing (DFT) with regard to first shock efficacy in spontaneous events. OBJECTIVE: This prespecified subanalysis assessed the predictive value of the PRAETORIAN score for defibrillation success in induced ventricular arrhythmias. METHODS: This multicenter investigator-initiated trial randomized 965 patients between DFT and PRAETORIAN score calculation after de novo S-ICD implantation. Successful DFT was defined as conversion of induced ventricular arrhythmia in <5 seconds from shock delivery within 2 attempts. Bidirectional chest radiographs were obtained after implantation. The predictive value of the PRAETORIAN score for DFT success was calculated for patients in the DFT arm. RESULTS: In total, 482 patients were randomized to undergo DFT. Of these patients, 457 (95%) underwent DFT according to protocol, of whom 445 (97%) had successful DFT and 12 (3%) had failed DFT. A PRAETORIAN score of ≥90 had a positive predictive value of 25% for failed DFT, and a PRAETORIAN score of <90 had a negative predictive value of 99% for successful DFT. A PRAETORIAN score of ≥90 was the strongest independent predictor for failed DFT (odds ratio 33.77; confidence interval 6.13-279.95; P < .001). CONCLUSION: A PRAETORIAN score of <90 serves as a reliable indicator for DFT success in patients with S-ICD, and a PRAETORIAN score of ≥90 is a strong predictor for DFT failure.

High incidence of implantable cardioverter defibrillator malfunctions during radiation therapy: neutrons as a probable cause of soft errors.

AIMS: To investigate the behaviour of the implantable cardioverter defibrillator (ICD) function during actual radiotherapy sessions. METHODS AND RESULTS: Fifteen patients with an ICD underwent 17 radiation treatments for cancer [cumulative dose to the tumour was between 16 Gray (Gy) and 70 Gy; photon beams with maximum energies between 6 megaelectronvolt (MeV) and 18 MeV were employed]. During every session, the ICD was programmed to a monitoring mode to prevent inappropriate therapy delivery. Afterwards, the ICDs were interrogated to ensure proper function. Calculated radiation dose at the ICD site was <1 Gy in all patients. In 5 out of 17 radiation treatments (29%) the ICDs showed 6 malfunctions (35%). We noticed four disturbances in the memory data or device resets during radiation treatment and one case of inappropriate ventricular fibrillation detection due to external noise. In one case a late device data error was observed. All malfunctions occurred at 10 and 18 MeV beam energies. CONCLUSION: Despite the fact that all recommended precautions were taken to minimize the damage to the ICDs during radiotherapy and the calculated dose to the ICDs was <1 Gy, in 29% of the treatments a malfunction occurred. We observed a possible correlation between the beam energy and the malfunctions. This correlation may be due to an interaction between neutrons produced in the head of the linear accelerator at beam energies ≥10 MeV, and boron-10 which is present in the integrated circuit.

Subcutaneous ICD implantation under ultrasound-guided serratus anterior plane block: Single-center experience in the Netherlands.

INTRODUCTION: To avoid general anesthesia (GA) and improve postoperative pain management for subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation there is a growing interest for alternative methods. We describe the first experience in the Netherlands of S-ICD implantation under Ultrasound-guided Serratus Anterior Plane Block (US-SAPB). METHODS: US-SAPB was performed 1 hour before S-ICD implantation. The two-incision technique was used and a pocket beneath the latissimus dorsi muscle was surgically created. Lidocaine was used to provide anesthesia of the skin. Sedation during defibrillation testing (DFT) was induced by intravenous Propofol. Periprocedural pain experience was monitored using the Numerical Rating Scale for Pain (NRS-Pain). The results were compared with a control group of patients undergoing S-ICD implantation under GA. RESULTS: Forty consecutive patients (29 Male/11 Female, median age 59 years (range 34-84 years), median body mass index 26 (range 17-41) underwent S-ICD implantation; Twenty patients under US-SAPB and twenty under GA. Median procedure time was 42 min. (range 28-60 min.) with no differences between both groups. In both groups implantations went successful and defibrillation was accomplished using 65 J. US-SAPB was successful in 19 of the 20 patients and GA was successful in all cases. Median NRS-Pain in the US-SAPB group was 2 (range 2-6) and in the GA group 4 (range 2-6). In the US-SAPB group 5 patients required additional opioids postoperatively compared to 10 patients in the GA group. CONCLUSIONS: S-ICD implantation under US-SAPB is feasible, safe and reduces the need for postoperative opioids significantly. S-ICD implantation under US-SAPB seems a good alternative for GA.

Left-Sided Humerus Fracture as an Unusual Complication of Defibrillation Threshold Testing Following S-ICD Implantation.

Comminuted subcapital humerus fracture as a complication of subcutaneous implantable cardioverter-defibrillator insertion is related to an abducted and externally rotated arm position during the defibrillation threshold test at which the current pathway is through the pectoral muscle. It is advisable to adduct the arm before defibrillation threshold testing. (Level of Difficulty: Beginner.).

Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.

BACKGROUND: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. OBJECTIVE: In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. METHODS: Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. RESULTS: From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS ≥ 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was ≥ 50% in 17/18 (94%) LVepi-paced patients. CONCLUSION: In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.

Implantation of a biventricular pacing system in a patient with a coronary sinus not communicating with the right atrium.

Intubation of the coronary sinus failed during implantation of a biventricular pacing system. An angiogram of the left coronary artery showed in the venous phase a coronary sinus not communicating with the right atrium. The coronary sinus was draining into a persistent left superior vena cava communicating with the left subclavian vein. The coronary sinus lead was successfully implanted through the persistent left superior vena cava, whereas the atrial and ventricular leads were implanted through the right superior vena cava in a conventional way.