A worldwide survey on incidence, management, and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: the POTTER-AF study.

AIMS: Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management, and outcome are sparse. METHODS AND RESULTS: This international multicentre registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553 729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed, at 214 centres in 35 countries. In 78 centres 138 patients [0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (P < 0.0001)] were diagnosed with an oesophageal fistula. Peri-procedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8% and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) [odds ratio 7.463 (2.414, 23.072) P < 0.001]. CONCLUSION: Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high.

Clinical outcome of out-of-hospital vs. in-hospital cardiac arrest survivors presenting with ventricular tachyarrhythmias.

Limited data regarding the prognostic impact of ventricular tachyarrhythmias related to out-of-hospital (OHCA) compared to in-hospital cardiac arrest (IHCA) is available. A large retrospective single-center observational registry with all patients admitted due to ventricular tachyarrhythmias was used including all consecutive patients with ventricular tachycardia (VT) and fibrillation (VF) on admission from 2002 to 2016. Survivors discharged after OHCA were compared to those after IHCA using multivariable Cox regression models and propensity-score matching for evaluation of the primary endpoint of long-term all-cause mortality at 2.5 years. Secondary endpoints were all-cause mortality at 6 months and cardiac rehospitalization at 2.5 years. From 2.422 consecutive patients with ventricular tachyarrhythmias, a total of 524 patients survived cardiac arrest and were discharged from hospital (OHCA 62%; IHCA 38%). In about 50% of all cases, acute myocardial infarction was the underlying disease leading to ventricular tachyarrhythmias with consecutive aborted cardiac arrest. Survivors of IHCA were associated with increased long-term all-cause mortality compared to OHCA even after multivariable adjustment (28% vs. 16%; log rank p = 0.001; HR 1.623; 95% CI 1.002-2.629; p = 0.049) and after propensity-score matching (28% vs. 19%; log rank p = 0.045). Rates of cardiac rehospitalization rates at 2.5 years were equally distributed between OHCA and IHCA survivors. In patients presenting with ventricular tachyarrhythmias, survivors of IHCA were associated with increased risk for all-cause mortality at 2.5 years compared to OHCA survivors.

Mechanisms of action behind the protective effects of proactive esophageal cooling during radiofrequency catheter ablation in the left atrium.

Proactive esophageal cooling for the purpose of reducing the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures is increasingly being used and has been Food and Drug Administration cleared as a protective strategy during left atrial RF ablation for the treatment of atrial fibrillation. In this review, we examine the evidence supporting the use of proactive esophageal cooling and the potential mechanisms of action that reduce the likelihood of atrioesophageal fistula (AEF) formation. Although the pathophysiology behind AEF formation after thermal injury from RF ablation is not well studied, a robust literature on fistula formation in other conditions (eg, Crohn disease, cancer, and trauma) exists and the relationship to AEF formation is investigated in this review. Likewise, we examine the abundant data in the surgical literature on burn and thermal injury progression as well as the acute and chronic mitigating effects of cooling. We discuss the relationship of these data and maladaptive healing mechanisms to the well-recognized postablation pathophysiological effects after RF ablation. Finally, we review additional important considerations such as patient selection, clinical workflow, and implementation strategies for proactive esophageal cooling.

Chronic kidney disease impairs prognosis in electrical storm.

BACKGROUND: The study sought to assess the prognostic impact of chronic kidney disease (CKD) in patients with electrical storm (ES). ES represents a life-threatening heart rhythm disorder. In particular, CKD patients are at risk of suffering from ES. However, data regarding the prognostic impact of CKD on long-term mortality in ES patients is limited. METHODS: All consecutive ES patients with an implantable cardioverter-defibrillator (ICD) were included retrospectively from 2002 to 2016. Patients with CKD (MDRD-GFR < 60 ml/min/1.73 m2) were compared to patients without CKD. The primary endpoint was all-cause mortality at 3 years. Secondary endpoints were in-hospital mortality, cardiac rehospitalization, recurrences of electrical storm (ES-R), and major adverse cardiac events (MACE) at 3 years. RESULTS: A total of 70 consecutive ES patients were included. CKD was present in 43% of ES patients with a median glomerular filtration rate (GFR) of 43.3 ml/min/1.73 m2. CKD was associated with increased all-cause mortality at 3 years (63% vs. 20%; p = 0.001; HR = 4.293; 95% CI 1.874-9.836; p = 0.001) and MACE (57% vs. 30%; p = 0.025; HR = 3.597; 95% CI 1.679-7.708; p = 0.001). In contrast, first cardiac rehospitalization (43% vs. 45%; log-rank p = 0.889) and ES-R (30% vs. 20%; log-rank p = 0.334) were not affected by CKD. Even after multivariable adjustment, CKD was still associated with increased long-term mortality (HR = 2.397; 95% CI 1.012-5.697; p = 0.047), as well as with the secondary endpoint MACE (HR = 2.520; 95% CI 1.109-5.727; p = 0.027). CONCLUSIONS: In patients with ES, the presence of CKD was associated with increased long-term mortality and MACE.

Atrial fibrillation increases the risk of recurrent ventricular tachyarrhythmias in implantable cardioverter defibrillator recipients.

BACKGROUND: Data regarding recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator (ICD) recipients according to atrial fibrillation is limited. OBJECTIVE: To assess the prognostic impact of atrial fibrillation on recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator recipients. METHODS: A large retrospective registry was used, including all ICD recipients with episodes of ventricular tachycardia or fibrillation from 2002 to 2016. Patients with atrial fibrillation were compared to those without atrial fibrillation. The primary endpoint was first recurrence of ventricular tachyarrhythmias at 5 years. Secondary endpoints comprised recurrences of ICD-related therapies, first cardiac rehospitalization and all-cause mortality at 5 years. Cox regression, Kaplan-Meier and propensity score-matching analyses were applied. RESULTS: A total of 592 consecutive ICD recipients were included (33% with atrial fibrillation). Atrial fibrillation was associated with reduced freedom from recurrent ventricular tachyarrhythmias (42% vs. 50%, log-rank P=0.004; hazard ratio 1.445, 95% confidence interval 1.124-1.858), mainly attributable to recurrent ventricular fibrillation in secondary-preventive ICD recipients. Accordingly, atrial fibrillation was associated with reduced freedom from first appropriate ICD therapies (31% vs. 42%, log-rank P=0.001; hazard ratio 1.598, 95% confidence interval 1.206-2.118). Notably, the primary endpoint of freedom from first episode of recurrent ventricular tachyarrhythmias was still reduced in those with atrial fibrillation compared to those without atrial fibrillation after propensity score matching. Regarding secondary endpoints, patients with atrial fibrillation still showed a trend towards reduced freedom from appropriate ICD therapies. CONCLUSIONS: Atrial fibrillation was associated with increased rates of recurrent ventricular tachyarrhythmias and appropriate device therapies in ICD recipients with ventricular tachyarrhythmias.

Effect of Anemia on the Prognosis of Patients with Ventricular Tachyarrhythmias.

This study evaluates the prognostic impact of anemia in patients presenting with ventricular tachyarrhythmias. The present longitudinal, observational, registry-based, monocentric cohort study included retrospectively all consecutive patients presenting with ventricular tachyarrhythmias on admission from 2002 to 2016. Anemic patients (hemoglobin levels <12.0 g/dl) were compared with non-anemic patients (hemoglobin levels ≥12.0 g/dl). The primary endpoint was all-cause mortality at 2.5 years. Secondary endpoints were cardiac death at 24 hours, all-cause mortality at index hospitalization, and the composite endpoint of cardiac death at 24 hours, recurrent ventricular tachyarrhythmias, and appropriate ICD therapies at 2.5 years. A total of 2,184 consecutive patients were included, of whom 30% were anemic and 70% non-anemic. Anemia was associated with the primary endpoint of all-cause mortality at 2.5 years (65% vs 29%, p = 0.001; HR = 2.441; 95% CI 2.086 to 2.856), cardiac death at 24 hours (26% vs 11%, p = 0.001), all-cause mortality at index hospitalization (45% vs 20%, p = 0.001), and the composite endpoint (35% vs 27%, p = 0.001; HR = 2.923; 95% CI 2.564 to 4.366). After multivariable adjustment, anemia was no longer associated with the composite endpoint. Predictors of adverse prognosis for anemics were CKD (HR = 2.191), LVEF <35% (HR = 1.651), cardiogenic shock (HR = 1.591), CPR (HR = 1.460), male gender (HR = 1.379), and age (HR = 1.017). In conclusion, anemic patients presenting with ventricular tachyarrhythmias were associated with increased long-term mortality at 2.5 years but not with the composite arrhythmic endpoint at 2.5 years. Predictors of adverse prognosis at 2.5 years were CKD, LVEF <35%, cardiogenic shock, CPR, male gender, and age.

Prognostic impact of coronary chronic total occlusion on recurrences of ventricular tachyarrhythmias and ICD therapies.

BACKGROUND: Despite a few studies evaluating the prognostic impact of coronary chronic total occlusion (CTO) in implantable cardioverter defibrillator (ICD) recipients, the impact of CTO on different types of recurrences of ventricular tachyarrhythmias, as well as their predictors has not yet been investigated in CTO patients. METHODS: A large retrospective registry was used including all consecutive patients with ventricular tachyarrhythmias undergoing coronary angiography at index from 2002 to 2016. Only ICD recipients with CTO were compared to patients without (non-CTO). Kaplan-Meier and Cox regression analyses were applied for the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years. Secondary end points comprised of the different types of recurrences, first appropriate ICD therapy and all-cause mortality at 5 years. RESULTS: From a total of 422 consecutive ICD recipients with ventricular tachyarrhythmias at index, at least one CTO was present in 25%. CTO was associated with the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years (55% vs. 39%; log rank p = 0.001; HR = 1.665; 95% CI 1.221-2.271; p = 0.001), as well as increased risk of first appropriate ICD therapy (40% vs. 31%; log rank p = 0.039; HR = 1.454; 95% CI 1.016-2.079; p = 0.041) and all-cause mortality at 5 years (26% vs. 16%; log rank p = 0.011; HR = 1.797; 95% CI 1.133-2.850; p = 0.013). Less developed collaterals (i.e., either ipsi- or contralateral compared to bilateral) and a J-CTO score ≥ 3 were strongest predictors of recurrences in CTO patients at 5 years. CONCLUSION: A coronary CTO even in the presence of less developed collaterals and more complex CTO category is associated with increasing risk of recurrent ventricular tachyarrhythmias at 5 years in consecutive ICD recipients.