Mortality and rehospitalization in patients with pre-existing implantable pacemakers undergoing catheter ablation are related to increased comorbidity burden-data from the German Ablation Registry.

BACKGROUND: Catheter ablation of atrial fibrillation and atrial flutter is routinely performed in patients with implantable devices. The aim of the present study was to assess success rates and potential complications in a large registry cohort of patients with cardiac pacemakers. METHODS AND RESULTS: The German Ablation Registry is a nationwide, prospective registry with a 1-year follow-up investigating patients who underwent catheter ablation of supraventricular arrhythmias in 51 German centers. The present analysis focussed on the presence of cardiac pacemakers in 591 patients undergoing catheter ablation of atrial fibrillation or atrial flutter. These were compared to 7393 patients without a pacemaker. Patients with pacemakers were significantly older and presented more comorbidities like diabetes, renal failure, cardiovascular disease, or previous stroke. One-year mortality (2.4% vs. 1.3%, p = 0.022) and a combined endpoint of death, myocardial infarction, and stroke (3.6% vs. 2.1%, p = 0.014) were significantly elevated in patients with pacemakers. Re-hospitalization was also more common in patients with a pacemaker (53.3% vs. 45.0%, p < 0.01). After adjustment for important comorbidities, pre-existing pacemaker systems did not show any negative effect. Procedural success was reported in 98.8% vs. 98.4% (p = 0.93). Device-related complications were only observed in 0.4% of patients with pacemakers. CONCLUSION: Patients with pacemaker systems undergoing catheter ablation of atrial fibrillation or atrial flutter demonstrate an increased risk of death, cardiovascular events, and re-hospitalization. This observation can be largely attributed to an older patient population and an increased rate of comorbidities.

Impact of intracardiac echocardiography usage on the safety of cryoballoon atrial fibrillation ablation: Subanalysis of the prospective FREEZE cluster cohort study.

INTRODUCTION: Cryoballoon ablation (CBA) aiming at pulmonary vein isolation (PVI) became a standardized atrial fibrillation (AF) ablation procedure. Life-threatening complications like cardiac tamponade exist. Intracardiac echocardiography (ICE) usage is associated with superior safety in radiofrequency ablation. It is unclear if ICE has an impact on safety of CBA. METHODS: The FREEZE Cohort (NCT01360008) subanalysis included patients undergoing "PVI only" CBA. Patients with intraprocedural transesophageal echocardiography were excluded. Group A comprises conventional, group B ICE-guided CBA. Periprocedural results were compared. RESULTS: From 2011 to 2016, a total of 4189 patients were enrolled, and 1906 (45.5%) were included in this subanalysis, split up in two groups (A: 1066 [55.9%], B: 840 [44.1%]). Group A was younger (60.6 ± 10.8 vs. 62.4 ± 10.5 years, p < .001), with smaller left atria (41 vs. 43 mm, p < .001), and less persistent AF (23.1 vs. 38.1%, p < .001). Procedure, left atrial, and fluoroscopy times were shorter in group A as compared to group B. Dose area product was significantly higher in group A (2911 vs. 2072 cGyxcm2 , p < .001). In-hospital major adverse cerebrovascular and cardiac event rates including two deaths in group A were not different between groups (0.5% vs. 0.1%, p = .18). The rate of total procedural (10.4% vs. 5.1%, p < .001) and major complications (3.2% vs. 1.3%, p < .001) was significantly higher in group A. Cardiac tamponade occurred significantly more frequently in group A (8 [0.8%] vs. 1 [0.1%], p = .046). Independent predictors for major complications were female sex (odds ratio [OR] 2.03, p = .03) and non-ICE usage (OR 2.38, p = .02). No differences were observed for persistent phrenic nerve palsy, nor for groin complications. CONCLUSION: CBA was significantly safer and required less radiation if ICE was used, although the procedures were more complex. The risk of groin complications was not increased with ICE usage. Non-ICE usage was the only modifiable independent predictor of major complications.

Cardiac defibrillator implantation in patients with syncope and inducible ventricular arrhythmia: insights from the German Device Registry.

History of syncope is an independent predictor for sudden cardiac death. Programmed stimulation may be considered for risk stratification, but data remain sparse among different populations. Here, we analyzed the prognostic value of inducible ventricular arrhythmia (VA) regarding clinical outcome in patients with syncope undergoing defibrillator implantation. Among 4196 patients enrolled in the prospective, multi-center German Device Registry, patients with syncope and inducible VA (n = 285, 6.8%) vs. those with a secondary preventive indication (n = 1885, 45.2%), defined as previously documented sustained ventricular tachycardia or ventricular fibrillation, serving as a control group were studied regarding demographics, device implantation and post-procedural adverse events. Patients with syncope and inducible VA (64.9 ± 14.4 years, 81.1% male) presented less frequently with congestive heart failure (15.1% vs. 29.1%; p < 0.001) and any structural heart disease (84.9% vs. 89.3%; p = 0.030) than patients with a secondary preventive indication (65.0 ± 13.8 years, 81.0% male). Whereas dilated cardiomyopathy (16.8% vs. 23.8%; p = 0.009) was less common, hypertrophic cardiomyopathy (5.6% vs. 2.8%; p = 0.010) and Brugada syndrome (2.1% vs. 0.3%; p < 0.001) were present more often. During 1-year-follow-up, mortality (5.1% vs. 8.9%; p = 0.036) and the rate of major adverse cardiac or cerebrovascular events (5.8% vs. 10.0%; p = 0.027) were lower in patients with syncope and inducible VA. Among patients with inducible VA, post-procedural adverse events including rehospitalization (27.6% vs. 21.7%; p = 0.37) did not differ between those with vs. without syncope. Taken together, patients with syncope and inducible VA have better clinical outcomes than patients with a secondary preventive defibrillator indication, but comparable outcomes to patients without syncope, which underlines the relevance of VA inducibility, potentially irrespective of a syncope.

Gender Differences in Epicardial Adipose Tissue and Plaque Composition by Coronary CT Angiography: Association with Cardiovascular Outcome.

Background: To investigate gender differences in epicardial adipose tissue (EAT) and plaque composition by coronary CT angiography (CCTA) and the association with cardiovascular outcome. Methods: Data of 352 patients (64.2 ± 10.3 years, 38% female) with suspected coronary artery disease (CAD) who underwent CCTA were retrospectively analyzed. EAT volume and plaque composition from CCTA were compared between men and women. Major adverse cardiovascular events (MACE) were recorded from follow-up. Results: Men were more likely to have obstructive CAD, higher Agatston scores, and a larger total and non-calcified plaque burden. In addition, men displayed more adverse plaque characteristics and EAT volume compared to women (all p < 0.05). After a median follow-up of 5.1 years, MACE occurred in 8 women (6%) and 22 men (10%). In multivariable analysis, Agatston calcium score (HR 1.0008, p = 0.014), EAT volume (HR 1.067, p = 0.049), and low-attenuation plaque (HR 3.82, p = 0.036) were independent predictors for MACE in men, whereas only low-attenuation plaque (HR 2.42, p = 0.041) showed predictive value for events in women. Conclusion: Women demonstrated less overall plaque burden, fewer adverse plaque characteristics, and a smaller EAT volume compared to men. However, low-attenuation plaque is a predictor for MACE in both genders. Thus, a differentiated plaque analysis is warranted to understand gender differences of atherosclerosis to guide medical therapy and prevention strategies.

Electrophysiology lab efficiency comparison between cryoballoon and point-by-point radiofrequency ablation: a German sub-analysis of the FREEZE Cohort study.

BACKGROUND: Pulmonary vein isolation (PVI) is recommended to treat paroxysmal and persistent atrial fibrillation (AF). This analysis aimed to assess the hospital efficiency of single-shot cryoballoon ablation (CBA) and point-by-point radiofrequency ablation (RFA). METHODS: The discrete event simulation used PVI procedure times from the FREEZE Cohort study to establish the electrophysiology (EP) lab occupancy time. 1000 EP lab days were simulated according to an illustrative German hospital, including 3 PVI cases per day using CBA at one site and RFA at the other. RESULTS: The analysis included 1560 CBA patients and 1344 RFA patients from the FREEZE Cohort. Some baseline patients' characteristics were different between groups (age, AF type, and some concomitant diseases), without being statistically associated to ablation procedure time. Mean procedure time was 122.2 ± 39.4 min for CBA and 160.3 ± 53.5 min for RFA (p < 0.0001). RFA was associated with a more than five-fold increase of cumulative overtime compared to CBA over the simulated period (1285 h with RFA and 253 h with CBA). 70.7% of RFA lab days included overtime versus 25.7% for CBA. CBA was associated with more days with an additional hour at the end of the EP lab shift compared to RFA (47.8% vs 11.5% days with one hour left, respectively). CONCLUSION: CBA is faster and more predictable than point-by-point RFA, and enables improvements in EP lab efficiency, including: fewer cumulative overtime hours, more days where overtime is avoided and more days with remaining time for the staff or for any EP lab usage. Clinical trial registration NCT01360008 (first registration 25/05/2011).

Prognostic Utility of Coronary Computed Tomography Angiography-derived Plaque Information on Long-term Outcome in Patients With and Without Diabetes Mellitus.

PURPOSE: To investigate the long-term prognostic value of coronary computed tomography angiography (cCTA)-derived plaque information on major adverse cardiac events (MACE) in patients with and without diabetes mellitus. MATERIALS AND METHODS: In all, 64 patients with diabetes (63.3±10.1 y, 66% male) and suspected coronary artery disease who underwent cCTA were matched with 297 patients without diabetes according to age, sex, cardiovascular risk factors, and statin and antithrombotic therapy. MACE were recorded. cCTA-derived risk scores and plaque measures were assessed. The discriminatory power to identify MACE was evaluated using multivariable regression analysis and concordance indices. RESULTS: After a median follow-up of 5.4 years, MACE occurred in 31 patients (8.6%). In patients with diabetes, cCTA risk scores and plaque measures were significantly higher compared with nondiabetic patients (all P <0.05). The following plaque measures were predictors of MACE using multivariable Cox regression analysis (hazard ratio [HR]) in patients with diabetes: segment stenosis score (HR=1.20, P <0.001), low-attenuation plaque (HR=3.47, P =0.05), and in nondiabetic patients: segment stenosis score (HR=1.92, P <0.001), Agatston score (HR=1.0009, P =0.04), and low-attenuation plaque (HR=4.15, P =0.04). A multivariable model showed a significantly improved C-index of 0.96 (95% confidence interval: 0.94-0.0.97) for MACE prediction, when compared with single measures alone. CONCLUSION: Diabetes is associated with a significantly higher extent of coronary artery disease and plaque features, which have independent predictive values for MACE. cCTA-derived plaque information portends improved risk stratification of patients with diabetes beyond the assessment of obstructive stenosis on cCTA alone with subsequent impact on individualized treatment decision-making.

Impact of cryoballoon application abortion due to phrenic nerve injury on reconnection rates: a YETI subgroup analysis.

AIMS: Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury (PNI) which is leading to premature abortion of the freeze cycle. Here, we analysed reconnection rates after CB-based PVI and PNI in a large-scale population during repeat procedures. METHODS AND RESULTS: In the YETI registry, a total of 17 356 patients underwent CB-based PVI in 33 centres, and 731 (4.2%) patients experienced PNI. A total of 111/731 (15.2%) patients received a repeat procedure for treatment of recurrent AF. In 94/111 (84.7%) patients data on repeat procedures were available. A total of 89/94 (94.7%) index pulmonary veins (PVs) have been isolated during the initial PVI. During repeat procedures, 22 (24.7%) of initially isolated index PVs showed reconnection. The use of a double stop technique did non influence the PV reconnection rate (P = 0.464). The time to PNI was 140.5 ± 45.1 s in patients with persistent PVI and 133.5 ± 53.8 s in patients with reconnection (P = 0.559). No differences were noted between the two populations in terms of CB temperature at the time of PNI (P = 0.362). The only parameter associated with isolation durability was CB temperature after 30 s of freezing. The PV reconnection did not influence the time to AF recurrence. CONCLUSION: In patients with cryoballon application abortion due to PNI, a high rate of persistent PVI rate was found at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03645577?term=YETI&cntry=DE&draw=2&rank=1 ClinicalTrials.gov Identifier: NCT03645577.

Association of epicardial adipose tissue with coronary CT angiography plaque parameters on cardiovascular outcome in patients with and without diabetes mellitus.

BACKGROUND AND AIMS: We aimed to evaluate the association of epicardial adipose tissue (EAT) with coronary CT angiography (CCTA) plaque parameters on cardiovascular outcome in patients with and without diabetes mellitus. METHODS: Data of 353 patients (62.9 ± 10.4 years, 62% male), who underwent CCTA as part of their clinical workup for the evaluation of suspected or known CAD, were retrospectively analyzed. EAT volume and plaque parameters from CCTA were compared in patients with diabetes (n = 63) and without diabetes (n = 290). Follow-up was performed to record adverse cardiovascular events. The predictive value to detect adverse cardiovascular events was assessed using concordance indices (CIs) and multivariable Cox proportional hazards analysis. RESULTS: In total, 33 events occurred after a median follow-up of 5.1 years. In patients with diabetes, EAT volume and plaque parameters were significantly higher than in patients without diabetes (all p < 0.05). A multivariable model demonstrated an incrementally improved C-index of 0.84 (95%CI 0.80-0.88) over the Framingham risk score and single measures alone. In multivariable Cox regression analysis EAT volume (Hazard ratio[HR] 1.21, p = 0.022), obstructive CAD (HR 1.18, p = 0.042), and ≥2 high-risk plaque features (HR 2.13, p = 0.031) were associated with events in patients with diabetes and obstructive CAD (HR 1.88, p = 0.017), and Agatston calcium score (HR 1.009, p = 0.039) in patients without diabetes. CONCLUSIONS: EAT, as a biomarker of inflammation, and plaque parameters, as an extent of atherosclerotic CAD, are higher in patients with diabetes and are associated with increased adverse cardiovascular outcomes. These parameters may help identify patients at high risk with need for more aggressive therapeutic and preventive care.

Phrenic Nerve Injury During Cryoballoon-Based Pulmonary Vein Isolation: Results of the Worldwide YETI Registry.

BACKGROUND: Cryoballoon-based pulmonary vein isolation (PVI) has emerged as an effective treatment for atrial fibrillation. The most frequent complication during cryoballoon-based PVI is phrenic nerve injury (PNI). However, data on PNI are scarce. METHODS: The YETI registry is a retrospective, multicenter, and multinational registry evaluating the incidence, characteristics, prognostic factors for PNI recovery and follow-up data of patients with PNI during cryoballoon-based PVI. Experienced electrophysiological centers were invited to participate. All patients with PNI during CB2 or third (CB3) and fourth-generation cryoballoon (CB4)-based PVI were eligible. RESULTS: A total of 17 356 patients underwent cryoballoon-based PVI in 33 centers from 10 countries. A total of 731 (4.2%) patients experienced PNI. The mean time to PNI was 127.7±50.4 seconds, and the mean temperature at the time of PNI was -49±8°C. At the end of the procedure, PNI recovered in 394/731 patients (53.9%). Recovery of PNI at 12 months of follow-up was found in 97.0% of patients (682/703, with 28 patients lost to follow-up). A total of 16/703 (2.3%) reported symptomatic PNI. Only 0.06% of the overall population showed symptomatic and permanent PNI. Prognostic factors improving PNI recovery are immediate stop at PNI by double-stop technique and utilization of a bonus-freeze protocol. Age, cryoballoon temperature at PNI, and compound motor action potential amplitude loss >30% were identified as factors decreasing PNI recovery. Based on these parameters, a score was calculated. The YETI score has a numerical value that will directly represent the probability of a specific patient of recovering from PNI within 12 months. CONCLUSIONS: The incidence of PNI during cryoballoon-based PVI was 4.2%. Overall 97% of PNI recovered within 12 months. Symptomatic and permanent PNI is exceedingly rare in patients after cryoballoon-based PVI. The YETI score estimates the prognosis after iatrogenic cryoballoon-derived PNI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03645577. Graphic Abstract: A graphic abstract is available for this article.

Catheter ablation of supraventricular tachycardia in patients with and without structural heart disease: insights from the German ablation registry.

AIM: To compare patient characteristics, safety and efficacy of catheter ablation of supraventricular tachycardia (SVT) in patients with and without structural heart disease (SHD) enrolled in the German ablation registry. METHODS AND RESULTS: From January 2007 until January 2010, a total of 12,536 patients (37.2% with known SHD) were enrolled and followed for at least one year. Patients with SHD more often underwent ablation for atrial flutter (45.8% vs. 20.9%, p < 0.001), whereas patients without SHD more often underwent ablation for atrioventricular nodal reentrant tachycardia (30.2% vs. 11.8%, p < 0.001) or atrioventricular reentrant tachycardia (9.1% vs. 1.6%, p < 0.001). Atrial fibrillation catheter ablation procedures were performed in a similar proportion of patients with and without SHD (38.1% vs. 36.9%, p = 0.21). Overall, periprocedural success rate was high in both groups. Death, myocardial infarction or stroke occurred in 0.2% and 0.1% of patients with and without SHD (p = 0.066). Major non-fatal complications prior to discharge were rare and did not differ significantly between patients with and without SHD (0.5% vs. 0.4%, p = 0.34). Kaplan-Meier mortality estimate at 1 year demonstrated a significant mortality increase in patients with SHD (2.6% versus 0.7%; p < 0.001). CONCLUSION: Patients with and without SHD undergoing SVT ablation exhibit similar success rates and low major complication rates, despite disadvantageous baseline characteristics in SHD patients. These data highlight the safety and efficacy of SVT ablation in patients with and without SHD. Nevertheless Kaplan-Meier mortality estimates at 1 year demonstrate a significant mortality increase in patients with SHD, highlighting the importance of treating the underlying condition and reliable anticoagulation if indicated.

Cryoballoon Ablation Strategy in Persistent Atrial Fibrillation.

Background: Cryoballoon ablation is established for pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (AF). The objective was to evaluate CBA strategy in consecutive patients with persistent AF in the initial AF ablation procedure. Material and Methods: Prospectively, patients with symptomatic persistent AF scheduled for AF ablation all underwent cryoballoon PVI. Technical enhancements, laboratory management, safety, single-procedure outcome, predictors of recurrence, and durability of PVI were evaluated. Results: From 2007 to 2020, a total of 1,140 patients with persistent AF, median age 68 years, underwent cryoballoon ablation (CBA). Median left atrial (LA) diameter was 45 mm (interquantile range, IQR, 8), and Congestive heart failure, Hypertension, Age ≥75 years (doubled), Diabetes mellitus, prior Stroke or TIA or thromboembolism (doubled), Vascular disease, Age 65 to 74 years, Sex category (CHA2DS2-VASc) score was 3. Acute isolation was achieved in 99.6% of the pulmonary veins by CBA. Median LA time and median dose area product decreased significantly over time (p < 0.001). Major complications occurred in 17 (1.5%) patients including 2 (0.2%) stroke/transitory ischemic attack (TIA), 1 (0.1%) tamponade, relevant groin complications, 1 (0.1%) significant ASD, and 4 (0.4%) persistent phrenic nerve palsy (PNP). Transient PNP occurred in 66 (5.5%) patients. No atrio-esophageal fistula was documented. Five deaths (0.4%), unrelated to the procedure, occurred very late during follow-up. After initial CBA, arrhythmia recurrences occurred in 46.6% of the patients. Freedom from atrial arrhythmias at 1-, and 2-year was 81.8 and 61.7%, respectively. Independent predictors of recurrence were LA diameter, female sex, and use of the first cryoballoon generation. Repeat ablations due to recurrences were performed in 268 (23.5%) of the 1,140 patients. No pulmonary vein (PV) reconduction was found in 49.6% of the patients and 73.5% of PVs. This rate increased to 66.4% of the patients and 88% of PVs if an advanced cryoballoon was used in the first AF ablation procedure. Conclusion: Cryoballoon ablation for symptomatic persistent AF is a reasonable strategy in the initial AF ablation procedure.

Cardiac computed tomography angiography-derived analysis of left atrial appendage morphology and left atrial dimensions for the prediction of atrial fibrillation recurrence after pulmonary vein isolation.

BACKGROUND: Left atrial appendage (LAA) is a potential source of atrial fibrillation (AF) triggers. HYPOTHESIS: LAA morphology and dimensions are associated with AF recurrence after pulmonary vein isolation (PVI). METHODS: From cardiac computed tomography angiography (CCTA), left atrial (LA), pulmonary vein (PV), and LAA anatomy were assessed in cryoballoon ablation (CBA) patients. RESULTS: Among 1103 patients undergoing second-generation CBA, 725 (65.7%) received CCTA with 473 (42.9%) qualifying for detailed LAA analysis (66.3 ± 9.5 years). Symptomatic AF reoccurred in 166 (35.1%) patients during a median follow-up of 19 months. Independent predictors of recurrence were LA volume, female sex, and mitral regurgitation ≥°II. LAA volume and AF-type were dependent predictors of recurrence due to their strong correlations with LA volume. LA volumes ≥122.7 ml (sensitivity 0.53, specificity 0.69, area under the curve [AUC] 0.63) and LAA volumes ≥11.25 ml (sensitivity 0.39, specificity 0.79, AUC 0.59) were associated with recurrence. LA volume was significantly smaller in females. LAA volumes showed no sex-specific difference. LAA morphology, classified as windsock (51.4%), chicken-wing (20.7%), cactus (12.5%), and cauliflower-type (15.2%), did not predict successful PVI (log-rank; p = 0.596). CONCLUSIONS: LAA volume was strongly correlated to LA volume and was a dependent predictor of recurrence after CBA. Main independent predictors were LA volume, female sex, and mitral regurgitation ≥°II. Gender differences in LA volumes were observed. Individual LAA morphology was not associated with AF recurrence after cryo-PVI. Our results indicate that preprocedural CCTA might be a useful imaging modality to evaluate ablation strategies for patients with recurrences despite successful PVI.

Discontinuation versus continuation of renin-angiotensin-system inhibitors in COVID-19 (ACEI-COVID): a prospective, parallel group, randomised, controlled, open-label trial.

BACKGROUND: SARS-CoV-2 entry in human cells depends on angiotensin-converting enzyme 2, which can be upregulated by inhibitors of the renin-angiotensin system (RAS). We aimed to test our hypothesis that discontinuation of chronic treatment with ACE-inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) mitigates the course o\f recent-onset COVID-19. METHODS: ACEI-COVID was a parallel group, randomised, controlled, open-label trial done at 35 centres in Austria and Germany. Patients aged 18 years and older were enrolled if they presented with recent symptomatic SARS-CoV-2 infection and were chronically treated with ACEIs or ARBs. Patients were randomly assigned 1:1 to discontinuation or continuation of RAS inhibition for 30 days. Primary outcome was the maximum sequential organ failure assessment (SOFA) score within 30 days, where death was scored with the maximum achievable SOFA score. Secondary endpoints were area under the death-adjusted SOFA score (AUCSOFA), mean SOFA score, admission to the intensive care unit, mechanical ventilation, and death. Analyses were done on a modified intention-to-treat basis. This trial is registered with ClinicalTrials.gov, NCT04353596. FINDINGS: Between April 20, 2020, and Jan 20, 2021, 204 patients (median age 75 years [IQR 66-80], 37% females) were randomly assigned to discontinue (n=104) or continue (n=100) RAS inhibition. Within 30 days, eight (8%) of 104 died in the discontinuation group and 12 (12%) of 100 patients died in the continuation group (p=0·42). There was no significant difference in the primary endpoint between the discontinuation and continuation group (median [IQR] maximum SOFA score 0·00 (0·00-2·00) vs 1·00 (0·00-3·00); p=0·12). Discontinuation was associated with a significantly lower AUCSOFA (0·00 [0·00-9·25] vs 3·50 [0·00-23·50]; p=0·040), mean SOFA score (0·00 [0·00-0·31] vs 0·12 [0·00-0·78]; p=0·040), and 30-day SOFA score (0·00 [10-90th percentile, 0·00-1·20] vs 0·00 [0·00-24·00]; p=0·023). At 30 days, 11 (11%) in the discontinuation group and 23 (23%) in the continuation group had signs of organ dysfunction (SOFA score ≥1) or were dead (p=0·017). There were no significant differences for mechanical ventilation (10 (10%) vs 8 (8%), p=0·87) and admission to intensive care unit (20 [19%] vs 18 [18%], p=0·96) between the discontinuation and continuation group. INTERPRETATION: Discontinuation of RAS-inhibition in COVID-19 had no significant effect on the maximum severity of COVID-19 but may lead to a faster and better recovery. The decision to continue or discontinue should be made on an individual basis, considering the risk profile, the indication for RAS inhibition, and the availability of alternative therapies and outpatient monitoring options. FUNDING: Austrian Science Fund and German Center for Cardiovascular Research.

Impact of age on the outcome of cryoballoon ablation as the primary approach in the interventional treatment of atrial fibrillation: Insights from a large all-comer study.

INTRODUCTION: The objective was to analyze the impact of patient age on clinical characteristics, procedural results, safety, and outcome of cryoballoon ablation (CBA) as the primary approach in the interventional treatment of symptomatic atrial fibrillation (AF). METHODS AND RESULTS: The single-center prospective observational study investigated consecutive patients who underwent initial left atrial ablation for symptomatic paroxysmal (PAF) or persistent AF (persAF). Age groups (A-F) of less than 40, 40-49, 50-59, 60-69, 70-79 and more than or equal to 80 years were evaluated. Follow-up (FU) included ECG, Holter monitoring and assessment of AF-symptoms. From 2012 to 2016, a total of 786 patients (64 ± 11 years, range 21-85) underwent CBA. With advancing age, more cardiovascular comorbidities and larger LA diameter were observed, more females were included (each p < .001). PAF (57%) and persAF (43%, p = .320) were equally distributed over all age groups. Age was neither related to procedural parameters, nor to the complication rate (3.9%, p = .233). Median FU was 38 months. Two non-procedure related noncardiac deaths occurred late during FU. Freedom from arrhythmia was independent of age at 18 months (p = .210) but decreased for patients more than or equal to 70 years at 24 months (p = .02). At 36 months, freedom from arrhythmia was 66%-74% (groups A-D), 54% (E) and 49% (F), respectively (p = .002). LA diameter and persAF were independent predictors, whereas age was a dependent predictor of recurrence. CONCLUSION: CBA as the primary approach in the initial ablation procedure is safe and highly effective in the young, middle aged, and elderly population. LA diameter and persAF, but not ageing, were independent predictors for arrhythmia recurrence.

Efficacy and complications of cavo-tricuspid isthmus-dependent atrial flutter ablation in patients with and without structural heart disease: results from the German Ablation Registry.

BACKGROUND: The impact of structural heart disease (SHD) on safety and efficacy of catheter ablation of cavo-tricuspid isthmus-dependent atrial flutter (AFLU) is unclear. In addition, recent data suggest a higher complication rate of AFLU ablation compared to the more complex atrial fibrillation (AF) ablation procedure. METHODS AND RESULTS: Within our prospective multicenter registry, 3526 consecutive patients underwent AFLU ablation at 49 German electrophysiological centers from 2007 to 2010. For the present analysis, the patients were divided into a group with SHD (n = 2164 [61.4%]; median age 69 years; 78.5% male) and a group without SHD (n = 1362 [38.6%]; 65 years; 70.3% male). In our study, SHD mainly encompasses coronary artery disease (52.6%), left ventricular ejection fraction ≤ 50% (47.6%), and hypertensive heart disease (28.0%). The primary ablation success (97%) and the incidence of major (0.2%) or moderate (1.2%) complications did not differ significantly between the two groups (P = 1.0 and 0.87, respectively). Vascular access site complications (0.6%), AV block III° (0.2%), and bleeding (≥ BARC II: 0.2%) were most common. After a median 562 days of follow-up, we observed a 2.92-fold higher one-year mortality (P < 0.0001) in patients with SHD. Patients' satisfaction with the ablation therapy (72.0% satisfied) was close to the overall subjective tachyarrhythmia-free rate (70.7%). CONCLUSIONS: The present analysis demonstrates that ablation of cavo-tricuspid isthmus dependent AFLU in patients with SHD has a comparable, excellent risk-benefit profile in our large "real-world" registry. Mortality rates expectedly are higher in patients with SHD and AFLU compared to patients without SHD. CLINICALTRIALS.GOV: NCT01197638, http://clinicaltrials.gov/ct2/show/NCT01197638.

Outcomes of ablation in Wolff-Parkinson-White-syndrome: Data from the German Ablation Registry.

AIMS: Catheter ablation is recommended for symptomatic WPW-syndrome. Commonly perceived low recurrence rates were challenged recently. We sought to identify patient strata at increased risk. METHOD: Of 12,566 patients enrolled at 52 German Ablation Registry sites from 2007 to 2010, 789 were treated for WPW-syndrome. Patients were included for symptomatic palpitations and tachycardia documentation. Follow-up duration was one year. Overall complications were defined as serious, access-related, and ablation-related. We adjudicated WPW-recurrence for re-ablation during follow-up. Risk strata included: admission for repeat ablation at registry entry; accessory pathway localization; antiarrhythmic medical treatment before the ablation. RESULTS: WPW-syndrome patients were 42.8 ± 16.2 years on average; 39.9% were women. A majority of 95.9% was symptomatic; in 84.4%, a tachycardia was documented. Seventy-six (9.6%) patients presented for repeat procedures. Accessory pathways were located in the left atrium (71.4%), right atrium (21.1%), septum (4.4%), or coronary sinus diverticula (2.1%). Prior antiarrhythmic medication was used in 43.7% of patients. No serious events occurred. The overall complication rate was 2.5% (ablation related 1.2%, access-related 1.3%). Major determinants for complications were presentation for re-ablation as registry index procedure (6.9% vs 2.2%; p = 0.016) and septal pathway location (left 2.0% vs septal 9.1%, p = 0.014). The overall re-ablation rate was 9.7%. Usage of prior antiarrhythmic medication was associated with higher recurrence rates (12.2% vs. 7.6%; p = 0.035). CONCLUSIONS: Patients at higher complication risk may be identified by repeat procedure and septal pathway location. Prior antiarrhythmic medication was associated with higher recurrence rates. Our findings may help improving peri-procedural patient management and information.

Improved long-term prognostic value of coronary CT angiography-derived plaque measures and clinical parameters on adverse cardiac outcome using machine learning.

OBJECTIVES: To evaluate the long-term prognostic value of coronary CT angiography (cCTA)-derived plaque measures and clinical parameters on major adverse cardiac events (MACE) using machine learning (ML). METHODS: Datasets of 361 patients (61.9 ± 10.3 years, 65% male) with suspected coronary artery disease (CAD) who underwent cCTA were retrospectively analyzed. MACE was recorded. cCTA-derived adverse plaque features and conventional CT risk scores together with cardiovascular risk factors were provided to a ML model to predict MACE. A boosted ensemble algorithm (RUSBoost) utilizing decision trees as weak learners with repeated nested cross-validation to train and validate the model was used. Performance of the ML model was calculated using the area under the curve (AUC). RESULTS: MACE was observed in 31 patients (8.6%) after a median follow-up of 5.4 years. Discriminatory power was significantly higher for the ML model (AUC 0.96 [95%CI 0.93-0.98]) compared with conventional CT risk scores including Agatston calcium score (AUC 0.84 [95%CI 0.80-0.87]), segment involvement score (AUC 0.88 [95%CI 0.84-0.91]), and segment stenosis score (AUC 0.89 [95%CI 0.86-0.92], all p < 0.05). Similar results were shown for adverse plaque measures (AUCs 0.72-0.82, all p < 0.05) and clinical parameters including the Framingham risk score (AUCs 0.71-0.76, all p < 0.05). The ML model yielded significantly higher diagnostic performance compared with logistic regression analysis (AUC 0.96 vs. 0.92, p = 0.024). CONCLUSION: Integration of a ML model improves the long-term prediction of MACE when compared with conventional CT risk scores, adverse plaque measures, and clinical information. ML algorithms may improve the integration of patient's information to enhance risk stratification. KEY POINTS: • A machine learning (ML) model portends high discriminatory power to predict major adverse cardiac events (MACE). • ML-based risk stratification shows superior diagnostic performance for MACE prediction over coronary CT angiography (cCTA)-derived risk scores or clinical parameters alone. • A ML model outperforms conventional logistic regression analysis for the prediction of MACE.

Catheter Ablation in Complex Atrial Arrhythmias: Pilot Study Evaluating a 3D Wide-Band Dielectric Imaging System.

BACKGROUND: Cryoballoon ablation (CBA) for pulmonary vein isolation (PVI) is a standard in atrial fibrillation (AF) ablation but might not be enough in complex atrial arrhythmias (AA). An open three-dimensional wide-band dielectric imaging system (3D-WBDIS) has been introduced to guide CBA. MATERIAL AND METHODS: Pilot study evaluating feasibility and safety of 3D-WBDIS in combination with CBA and optional radiofrequency ablation (RFA) in patients with complex AA defined as (1) history of persistent AF, (2) additional atrial tachycardia/flutter, or (3) previous left atrial ablation. RESULTS: Prospectively, seventeen patients, 68.9 ± 12.2 years of age, with complex AA were enrolled. In 70 pulmonary veins (PV), balloon positioning maneuvers (n = 129) were guided additionally by the occlusion tool (1.84/PV). Compared to angiography, its sensitivity and specificity was 94.5, and 85%, respectively. CBA-PVI was achieved in 100% of PVs including variants. In 68 maps, the median number of mapping points was 251.0 (interquartile range (IQR) 298.0) with a median map volume of 52.8 (IQR 83.9) mL. Following CBA, six additional arrhythmias (two right and two left atrial flutter, one left atrial appendage tachycardia, and one atrioventricular nodal reentry tachycardia) were identified and successfully ablated by means of RFA in five patients (29.4%). Left atrial and fluoroscopy times were 88 (IQR 40) and 20 (IQR 10) minutes, respectively. Dose area product was 1,100 (IQR 1252) cGyxcm2. Freedom from AA after 6 months follow-up time and 90 days blanking period was documented in 10/17 (59%) patients, and 8/17 (47%) without a blanking period. No major complication was observed. CONCLUSION: The combined use of CBA with optional RFA guided by a novel 3D-WBDIS is feasible and safe in patients suffering from complex AA. The occlusion tool shows high sensitivity and specificity for assessment of the balloon occlusion. Additional arrhythmias were successfully mapped and ablated. Short-term outcome is promising, and subsequent prospective, larger outcome studies are necessary to confirm our observations.