Cardiac resynchronization therapy in patients with a coronary sinus reducer: a case series.

Background: Reducing venous drainage of the coronary sinus is a promising intervention for refractory angina. Coronary Sinus Reducer (CSR) System™ effectively treats patients with refractory angina, possibly by increasing coronary collateral circulation, and leads to an improvement in their symptoms and quality of life. In patients with impaired left ventricular function and electrocardiographic dyssynchrony, cardiac resynchronization therapy (CRT) is an established treatment. However, there is only one published case report of CRT in a patient implanted with a CSR system. We present the first case series of CRT in patients implanted with the CSR system. Case summary: This case series describes three patients. The first case demonstrated that CRT is feasible in patients implanted with a CSR system. The second case is the first report of a left ventricular lead extraction after CSR, and the third case was complicated due to the patient's medical history; however, CSR system implantation was feasible without major complications. Discussion: Our results suggest that CRT is feasible in patients implanted with a CSR system, and lead extraction after CSR system implantation is possible. However, lead extraction in cases of severe adhesions around the CSR system and the coronary sinus may be associated with a high risk of complications; alternative options should be discussed at an early stage.

Transvenous Lead Extraction during Cardiac Implantable Device Upgrade: Results from the Multicenter Swiss Lead Extraction Registry.

BACKGROUND: Device patients may require upgrade interventions from simpler to more complex cardiac implantable electronic devices. Prior to upgrading interventions, clinicians need to balance the risks and benefits of transvenous lead extraction (TLE), additional lead implantation or lead abandonment. However, evidence on procedural outcomes of TLE at the time of device upgrade is scarce. METHODS: This is a post hoc analysis of the investigator-initiated multicenter Swiss TLE registry. The objectives were to assess patient and procedural factors influencing TLE outcomes at the time of device upgrades. RESULTS: 941 patients were included, whereof 83 (8.8%) had TLE due to a device upgrade. Rotational mechanical sheaths were more often used in upgraded patients (59% vs. 42.7%, p = 0.015) and total median procedure time was longer in these patients (160 min vs. 105 min, p < 0.001). Clinical success rates of upgraded patients compared to those who received TLE due to other reasons were not different (97.6% vs. 93.0%, p = 0.569). Moreover, multivariable analysis showed that upgrade procedures were not associated with a greater risk for complications (HR 0.48, 95% confidence interval 0.14-1.57, p = 0.224; intraprocedural complication rate of upgraded patients 7.2% vs. 5.5%). Intraprocedural complications of upgraded patients were mostly associated with the implantation and not the extraction procedure (67% vs. 33% of complications). CONCLUSIONS: TLE during device upgrade is effective and does not attribute a disproportionate risk to the upgrade procedure.

Single center experience with the novel rotating dilator sheath TightRailTM Sub-C in transvenous lead extraction.

INTRODUCTION: Transvenous lead extraction has become a frequent procedure in the context of device lead management and various tools are available. The aim of this study was to investigate the efficacy and safety of the novel short rotating dilator sheath TightRailTM Sub-C (Sub-C) in transvenous lead extraction. METHODS: For this retrospective single-center analysis, we included consecutive patients undergoing transvenous lead extraction using the Sub-C from January 2018 until February 2020 at the University Heart Center Zurich. RESULTS: A total of 87 leads were extracted within 45 patients using the Sub-C extraction sheath. The mean dwell time of the leads was 112 ± 9.1 months. Complete procedural success was achieved in 95.6% (43/45) and clinical procedural success in 97.8% (44/45). Two major complications (4.4%, 2/45) occurred, but neither was directly related to the Sub-C. CONCLUSION: This retrospective single-center analysis suggests that transvenous lead extraction with a routine use of the TightRailTM Sub-C extraction sheath is a safe strategy resulting in high success rates that may offer useful theoretical benefits. Future studies are needed to evaluate the incremental benefit of a routine use of short extraction sheaths including the Sub-C during TLE procedures.

Sense-B-noise: an enigmatic cause for inappropriate shocks in subcutaneous implantable cardioverter defibrillators.

AIMS: Subcutaneous implantable cardioverter defibrillators (S-ICDs) are well established. However, inappropriate shocks (IAS) remain a source of concern since S-ICDs offer very limited troubleshooting options. In our multicentre case series, we describe several patients who experienced IAS due to a previously unknown S-ICD system issue. METHODS AND RESULTS: We observed six patients suffering from this novel IAS entity. The IAS occurred exclusively in primary or alternate S-ICD sensing vector configuration (therefore called 'Sense-B-noise'). IAS were caused by non-physiologic oversensing episodes characterized by intermittent signal saturation, diminished QRS amplitudes, and disappearance of the artefacts after the IAS. Noise/oversensing could not be provoked by manipulation, X-ray did not show evidence for lead/header issues and impedance measurements were within normal limits. The pooled experience of our centres implies that up to ∼5% of S-ICDs may be affected. The underlying root cause was discussed extensively with the manufacturer but remains unknown and is under further investigation. CONCLUSION: Sense-B-noise is a novel cause for IAS due to non-physiologic signal oversensing, arising from a previously unknown S-ICD system issue. Sense-B-noise may be suspected if episodes of signal saturation in primary or alternate vector configuration are present, oversensing cannot be provoked, and X-ray and electrical measurements appear normal. The issue can be resolved by reprogramming the device to secondary sensing vector.

Performance and safety of temperature- and flow-controlled radiofrequency ablation for ventricular arrhythmia.

AIMS: High-power ablation is effective for ventricular arrhythmia ablation; however, it increases the risk of steam pops. The aim of this study was to define the safety and efficacy of QMODE ablation in the ventricle and the risk of steam pop. METHODS AND RESULTS: Consecutive patients undergoing ventricular ablation using QDOT were included in a prospective single-centre registry. Procedural data, complications, and follow-up were systematically analysed and compared with a historical ventricular tachycardia (VT) and premature ventricular complexes (PVC) cohort ablated using STSF. QMODE (≤50 W) ablation was performed in 107 patients [age 62 ± 13 years; 76% male; VT (n = 41); PVC (n = 66)]. A total of 2456 applications were analysed [power: 45.9 ± 5.0 W with minimal power titration (90% > 95% max power); duration 26 ± 8 s; impedance drop 9.4 ± 4.7 Ω; ablation index: 569 ± 163; mean-max temperature 44.3 ± 2.6°C]. Ventricular tachycardia ablation was associated with shorter radiofrequency (RF) time and a trend towards shorter procedure times using QDOT (QDOT vs. STSF: 20.1 ± 14.7 vs. 31 ± 17 min; P = 0.002, 151 ± 59 vs. 172 ± 48 min; P = 0.06). Complications, VT recurrence, and mortality rates were comparable (QDOT vs. STSF: 2% vs. 2%; P = 0.9, 24% vs. 27%; P = 0.82, and 2% vs. 4%; P = 0.67). Five audible steam pops (0.02%) occurred. Premature ventricular complex ablation was associated with comparable RF and procedure times (QDOT vs. STSF: 4.8 ± 4.6 vs. 3.9 ± 3.1 min; P = 0.25 and 96.1 ± 31.9 vs. 94.6 ± 24.7 min; P = 0.75). Complication and PVC recurrence were also comparable (QDOT vs. STSF: 0% vs. 3%; P = 0.17 and 19% vs. 22%; P = 0.71). CONCLUSION: Ventricular ablation using QMODE ≤ 50 W is safe and effective for both VT and PVC ablation and is associated with a low risk for steam pop.

Biventricular Arrhythmogenic Cardiomyopathy Associated with a Novel Heterozygous Plakophilin-2 Early Truncating Variant.

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is a hereditary condition that can cause sudden cardiac death in young, frequently athletic individuals under the age of 35 due to malignant arrhythmias. Competitive and endurance exercise may hasten the onset and progression of ARVC, leading to right ventricular dysfunction and potentially fatal ventricular arrhythmias earlier in life. In this article, we present a novel, pathogenic, early truncating heterozygous variant in the PKP2 gene that causes biventricular arrhythmogenic cardiomyopathy and affects a family, of which the only member with the positive phenotype is a competitive endurance athlete.

Early Experience with the Biotronik Protego ICD Lead.

Background: In the last decade, newer generation ICD leads have been developed based on mechanistic insides of priorly failing leads. The aim of our study was to assess the long-term performance and mechanisms of failure of the 2013-introduced Biotronik Protego ICD lead in a real-world population. Methods: All patients, who underwent implantation of a Protego ICD lead at the Heart Centre Lucerne (Lucerne, Switzerland) between November 2013 and March 2017, were followed up with semi-annual device-controls. The primary endpoint was defined as lead failure, secondary endpoints compromised all-cause death, (in)appropriate shocks and the need for reintervention. Results: A total of 64 patients (mean age 66.7 ± 8.7 years, 30% female) underwent implantation of a Protego ICD lead: 78% for primary prevention, 53% had underlying ischemic heart disease, and 40.6% had a dilated cardiomyopathy (DCM). Mean left ventricular ejection fraction (LVEF) was 32.6 ± 10.5%. A total of 24 patients were treated with cardiac resynchronization therapy (CRT), and their baseline LVEF improved from 27.8 ± 7.3% before to 39.8 ± 12.5 after implantation (p < 0.001). Mean time to follow-up was 5.5 ± 0.9 years. Overall, 14 patients (26.6%) suffered from at least one episode of sustained ventricular tachycardia; in total 10 patients (15.6%) died. Two patients experienced lead failure due to lead fracture after 5.5 and 5.7 years, which was clinically apparent by an abrupt rise in lead impedance (>2000 Ω) and by repetitive inappropriate shocks, respectively. Conclusions: In this retrospective observational study, the calculated annual lead failure rate of the Biotronik Protego ICD lead was 0.59% per patient­thus, the durability and long-term performance seem to be promising.

Deep sedation with propofol in patients undergoing left atrial ablation procedures-Is it safe?

Background: Catheter ablation for atrial fibrillation (AF) or left atrial tachycardia is well established. To avoid body movement and pain, sedative and analgesic agents are used. Objective: The aim was to investigate safety of sedation/anti-pain protocol administered by electrophysiology (EP) staff. Methods: A total of 3211 consecutive patients (61% male) undergoing left atrial ablation for paroxysmal AF (37.1%), persistent AF (35.3%) or left atrial tachycardia (27.6%) were included. Midazolam, fentanyl, and propofol were administered by EP staff. In case of respiratory depression, endotracheal intubation (eIT) or noninvasive ventilation (NIV) was implemented. Risk factors for eIT or NIV were analyzed. Results: Mean doses of propofol, midazolam, and fentanyl were 33.7 ± 16.7 mg, 3 ± 11.1 mg, and 0.16 ± 2.2 mg, respectively. Norepinephrine was administered in 396 of 3211 patients (12.3%) because of blood pressure drop (mean arterial pressure <60 mm Hg). NIV was necessary in 47 patients (1.5%) and eIT in 1 patient (0.03%). Procedure duration, high body mass index (BMI), high CHADS2-VASC2 score, high age, low glomerular filtration rate, diabetes mellitus, and low baseline oxygen saturation were associated with NIV or eIT. The only independent predictor for NIV/eIT was high BMI (>30.1 ± 9.0 kg/m2). Therefore, patients with a BMI of ≥30 had a 40% higher risk for the need of NIV/eIT during the procedure in our study. Conclusion: Sedation/anti-pain control including midazolam, propofol, and fentanyl administered by EP staff is safe, with only 1.53% requirement of NIV/eIT. High BMI (>30 kg/m2) emerged as an independent predictor for eIT/NIV.

Long-term follow-up after the use of the as low as reasonably achievable radiation protocol in patients with symptomatic supraventricular tachycardia.

INTRODUCTION: Catheter ablation is an effective treatment modality for patients with symptomatic supraventricular tachycardia (SVT), such as atrioventricular nodal re-entrant tachycardia (AVNRT) and typical atrial flutter (TAF). With increasingly invasive electrophysiological procedures and continuous development of ablation techniques, the aim is to reduce radiation doses for patients and the electrophysiological team. Modern methods that combine the "as low as reasonably achievable" (ALARA) protocol and three-dimensional mapping systems are now state-of-the-art procedures in the treatment of arrhythmia. This study aimed to compare the effectiveness and long-term success of the ALARA approach compared to those of conventional therapy, without using modern mapping systems. METHODS: Sixty-one patients with symptomatic SVT (37 with AVNRT, 19 with isthmus-dependent counter-clockwise TAF, and five with other SVTs) were randomised into two groups: the ALARA and conventional groups. All patients underwent successful SVT ablation. Clinical and remote follow-up was available for 59 patients after a mean period of 3.2 years. RESULTS: The mean fluoroscopy time was significantly shorter in the ALARA group (1.1 min vs. 8.4 min, p < 0.01). Regarding complications and recurrences, during a median follow-up period of 3.2 years, eight patients (13.5%) had recurrences, all of which occurred in the conventional group. CONCLUSION: This study confirmed a significantly lower radiation burden for patients and the entire electrophysiological team with the ALARA approach and a significantly increased risk of recurrence and complications with the conventional approach. The reduction in radiation time and high long-term success indicate the utility of the ALARA protocol in daily practice.

Role of the Ambulatory Assessed Apnea-Hypopnea Index for Predicting Recurring Atrial Fibrillation After Ablation Therapy.

Catheter ablation is an effective treatment for atrial fibrillation (AF). Obstructive sleep apnea (OSA) is a known risk factor for recurrent AF. The apnea-hypopnea index (AHI) is a measurement tool to screen patients for OSA. We sought to evaluate if the ambulatory assessed AHI is associated with AF recurrence following AF catheter ablation. 187 patients with paroxysmal (n = 155) or early persistent (n = 32) AF presenting for catheter ablation were included in the study. AHI was determined prior to ablation using an ambulatory screening device. All patients underwent pulmonary vein isolation (PVI). In patients with early persistent AF (17%) additional ablation of complex fractionated atrial electrograms (CFAE) was performed. Clinical follow-up was available after 3 and 12 months including 7-day Holter-ECG. All 187 patients (60.3 ± 11.4 years, 64.2% male) completed the 3 months follow-up and 170 patients the 12 months follow-up. A pathological AHI ≥15 was found in 45/187 (24.1%) patients. Additional CFAE did not differ between patients with an AHI ≥15 and AHI <15 (p = 0.663). After 3 months, 12/41 (29.3%) patients with AHI ≥15 showed recurrent AF compared to 24/146 (16.4%) patients with AHI <15 (p = 0.066). After 12 months, AHI ≥15 was associated with a significant higher rate of AF recurrence of 47.4% (18/38) versus 26.5% (35/132) in patients with AHI <15 (p = 0.014). In the logistic regression analysis AHI ≥15 was an independent predictor of recurrent AF at 12 months (p = 0.011). In conclusion, ambulatory assessed AHI ≥15 is associated with increased risk for AF recurrence following catheter ablation. OSA screening should be performed in AF patients as it might influence catheter ablation success.

Release of high-sensitive TROPonin T by implantation of an entirely subcutaneous Implantable Cardioverter-defibrillator compared to a conventional transvenous approach: the TROPIC registry.

PURPOSE: Implantation of a subcutaneous implantable cardioverter-defibrillator (S-ICD) has become an alternative option when a conventional transvenous approach is not suitable. The myocardial damage caused by S-ICD implantation appears to be minimal despite mandatory defibrillation threshold (DFT) testing. However, there has not been a direct comparison with the traditional transvenous placement of a single-chamber ICD (VVI-ICD). The aim of this study was to determine the extent of myocardial damage by analysing the changes in serum levels of cardiac enzymes after S-ICD implantation in comparison with VVI-ICD. METHODS: In 43 patients who received an S-ICD system, differences in serum levels of high-sensitive troponin T (ΔhsTnT) and creatine kinase total (ΔCK) and muscle brain fraction (ΔCK-MB) were acquired by blood sampling before and the day after implantation. The control group consisted of 43 patients from the TropShock study who had received a transvenous VVI-ICD without DFT. RESULTS: After S-ICD implantation and testing procedure, ΔhsTnT (0.000 ng/ml, IQR - 0.003-0.002 ng/ml) was significantly lower than after conventional VVI-ICD implantation (0.018 ng/ml, IQR 0.004-0.032 ng/ml; p < 0.001). There was no significant difference in CK (ΔCKS-ICD 85.0 U/I, IQR 30.5-225.8 U/I vs ΔCKVVI-ICD 69.5 U/I, IQR 22.9-172.3 U/I; p = 0.357), but there was a significant difference in CK-MB (ΔCK-MBS-ICD of - 0.60, IQR - 2.60-1.0 vs ΔCK-MBVVI-ICD 1.0, IQR - 1.08-3.18; p = 0.030). CONCLUSION: S-ICD implantation causes less myocardial damage than VVI-ICD implantation evidenced by ΔhsTnT and ΔCK-MB.

Security millimetre wave body scanner safe for patients with leadless pacemakers or subcutaneous implantable cardioverter-defibrillators.

PURPOSE: This study was designed to evaluate the electromagnetic interference (EMI) effects and safety of the new security screening millimetre wave body scanners (MWBSs) for patients with rare cardiac implantable electronic devices (CIEDs). METHODS: We identified 73 patients with either entirely subcutaneous implantable cardioverter-defibrillators (S-ICD) or leadless pacemakers (LPM) attending routine device follow-up. CIED programming was optimised for the detection of EMI occurrence, and high-voltage therapy was disabled. Patients then underwent millimetre wave body scans under continuous ECG monitoring. Scanning was performed at the recommended distance as well as in close proximity to the scanner emulating accidental exposure. CIED function was observed for EMI effects. RESULTS: There were no episodes of inhibition of pacing in the leadless pacemaker subgroup, no oversensing in the S-ICD subgroup and no spontaneous device reprogramming in any group. There was no change in pacing or sensing thresholds, and S-ICD vector eligibility remained unchanged after scanning with the MWBS. No CIEDs were identified by the MWBS during the study. CONCLUSION: No EMI events were detected during the use of MWBSs by patients with either S-ICDs or LPMs. This data should be reassuring for patients suggesting that they can undergo security body scans without worries or disclosure of their CIED status.

Cardiac resynchronisation therapy in patients with left bundle branch block with residual conduction.

AIM: To evaluate whether left bundle branch block with residual conduction (rLBBB) is associated with worse outcomes after cardiac resynchronisation therapy (CRT). METHODS: All consecutive CRT implants at our institution between 2006 and 2013 were identified from our local device registry. Pre- and post-implant patient specific data were extracted from clinical records. RESULTS: A total of 690 CRT implants were identified during the study period. Prior to CRT, 52.2% of patients had true left bundle branch block (LBBB), 19.1% a pacing-induced LBBB (pLBBB), 11.2% a rLBBB, 0.8% a right bundle branch block (RBBB), and 16.5% had a nonspecific intraventricular conduction delay (IVCD) electrocardiogram pattern. Mean age at implant was 67.5 years (standard deviation [SD] = 10.6), mean left ventricular ejection fraction (LV EF) was 25.7% (SD = 7.9%), and mean QRS duration was 158.4 ms (SD = 32 ms). After CRT, QRS duration was significantly reduced in the LBBB (p < 0.001), pLBBB (p < 0.001), rLBBB (p < 0.001), RBBB (p = 0.04), and IVCD groups (p = 0.03). LV EF significantly improved in the LBBB (p < 0.001), rLBBB (p = 0.002), and pLBBB (p < 0.001) groups, but the RBBB and IVCD groups showed no improvement. There was no significant difference in mortality between the LBBB and rLBBB groups. LV EF post-CRT, chronic kidney disease, hyperkalaemia, hypernatremia, and age at implant were significant predictors of mortality. CONCLUSION: CRT in patients with rLBBB results in improved LV EF and similar mortality rates to CRT patients with complete LBBB. Predictors of mortality post-CRT include post-CRT LV EF, presence of CKD, hyperkalaemia, hypernatremia, and older age at implant.

Use of the wearable cardioverter-defibrillator - the Swiss experience.

INTRODUCTION: Sudden cardiac death caused by malignant arrhythmia can be prevented by the use of defibrillators. Although the wearable cardioverter defibrillator (WCD) can prevent such an event, its role in clinical practice is ill defined. We investigated the use of the WCD in Switzerland with emphasis on prescription rate, therapy adherence and treatment rate. MATERIALS AND METHODS: The Swiss WCD Registry is a retrospective observational registry including patients using a WCD. Patients were included from the first WCD use in Switzerland until February 2018. Baseline characteristics and data on WCD usage were examined for the total study population, and separately for each hospital. RESULTS: From 1 December 2011 to 18 February 2018, a total of 456 patients (67.1% of all WCDs prescribed in Switzerland and 81.1% of all prescribed in the participating hospitals) were included in the registry. Up to 2017 there was a yearly increase in the number of prescribed WCDs to a maximum of 271 prescriptions per year. The mean age of patients was 57 years (± 14), 81 (17.8%) were female and mean left ventricular ejection fraction (EF) was 32% (± 13). The most common indications for WCD use were new-onset ischaemic cardiomyopathy (ICM) with EF ≤35% (206 patients, 45.2%), new-onset nonischaemic cardiomyopathy (NICM) with EF ≤35% (115 patients, 25.2%), unknown arrhythmic risk (83 patients, 18.2%), bridging to implantable cardioverter-defibrillator implantation or heart transplant (37 patients, 8.1%) and congenital/inherited heart disease (15 patients, 3.3%). Median wear duration was 58 days (interquartile range [IQR] 31–94) with a median average daily wear time of 22.6 hours (IQR 20–23.2). Seventeen appropriate therapies from the WCD were delivered in the whole population (treatment rate: 3.7%) to a total of 12 patients (2.6% of all patients). The most common underlying heart disease in patients with a treatment was ICM (13/17, 76.5%). There were no inappropriate treatments. CONCLUSION: The use of WCDs has increased in Switzerland over the years for a variety of indications. There is high therapy adherence to the WCD, and a treatment rate comparable to previously published registry data.  .

Early recurrence after pulmonary vein isolation is associated with inferior long-term outcomes: Insights from a retrospective cohort study.

AIMS: The aim of this retrospective cohort study was to assess the influence of early recurrence (ER) after pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) on long-term outcomes and to identify clinical variables associated with ER. METHODS: We retrospectively collected clinical and procedural data from 1285 patients with paroxysmal AF who underwent PVI from 2011 to 2016. Kaplan-Meier, receiver operating characteristic (ROC) curve, logistic and Cox regression analyses were performed to analyze the influence of ER on long-term outcomes. RESULTS: ER was observed in 13% of patients. Kaplan-Meier analyses showed significantly different outcomes in 1285 patients with and without ER (49% vs 74%, log rank P < .01) and in 286 patients in the subgroup that underwent reablation (44% vs 79%, log rank P < .01). The hazard ratio (HR) of ER was 1.7 within 48 hours (5% of patients), 2.7 within 1 month (5%), 3.0 within 2 months (2%), and 6.4 within 3 months (1%) for late recurrence (LR), P < .01. ROC analysis (area under the curve [AUC] = 0.79) resulted in 70.3% sensitivity and 74.2% specificity for a 14-day blanking period, and 53.1% sensitivity and 85.5% specificity for a 30-day blanking period. Female patients (odds ratio [OR] 1.69, P < .01) and those with diabetes (OR 1.95, P = .01) were at higher risk for ER. CONCLUSIONS: ER is observed in a substantial number of patients with paroxysmal AF after PVI and has a continuous direct effect on LR according to the timing of ER. Randomized trials are required to assess the safety and effects of reablations in a shortened blanking period on long-term outcomes.

Myocardial Minimal Damage After Rapid Ventricular Pacing - the prospective randomized multicentre MyDate-Trial.

Therapy of choice for the primary and secondary prevention of sudden cardiac death is the implantation of an implantable cardioverter defibrillator (ICD). Whereas appropriate and inappropriate ICD shocks lead to myocardial microdamage, this is not known for antitachycardia pacing (ATP). In total, 150 ICD recipients (66 ± 12 years, 81.3% male, 93.3% primary prevention, 30.0% resynchronization therapy) were randomly assigned to an ICD implantation with or without intraoperative ATP. In the group with ATP, the pacing maneuver was performed twice, each time applying 8 impulses à 6 Volt x 1.0 milliseconds to the myocardium. High sensitive Troponin T (hsTnT) levels were determined prior to the implantation and thereafter. There was no significant difference in the release of hsTnT between the two randomization groups (delta TnT without ATP in median 0.010 ng/ml [min. -0.016 ng/ml-max. 0.075 ng/ml] vs. with ATP in median 0.013 ng/ml [min. -0.005-0.287 ng/ml], p = 0.323). Setting a hsTnT cutoff of 0.059 ng/dl as a regularly augmented postoperative hsTnT level, no relevant difference between the two groups regarding the postoperative hsTnT levels above this cutoff could be identified (without ATP n = 10 [14.7%] vs. with ATP n = 16 [21.9%], p = 0.287). There was no significant difference in the release of high sensitive Troponin between patients without intraoperative ATP compared to those with intraoperative ATP. Hence, antitachycardia pacing does not seem to cause significant myocardial microdamage. This may further support its use as a painless and efficient method to terminate ventricular tachycardia in high-risk patients.