Single-catheter simplified stepwise approach to persistent atrial fibrillation ablation: A feasibility study.

BACKGROUND: The strategy for atrial fibrillation ablation in persistent atrial fibrillation remains controversial. A single-catheter approach was recently validated for pulmonary vein isolation. AIM: To evaluate the feasibility of this approach to performing persistent atrial fibrillation ablation, including pulmonary vein isolation and atrial lines, if needed. METHODS: We prospectively included 159 consecutive patients referred to our centre for a first persistent atrial fibrillation ablation between January 2018 and December 2018. All patients underwent pulmonary vein isolation. If the patient was still in atrial fibrillation (spontaneously or inducible), we subsequently performed a stepwise approach, including roof line, anterior mitral line, posterior box lesion and cavotricuspid isthmus line. Finally, if patient remained in atrial fibrillation at the end of the procedure, a synchronized direct-current cardioversion was applied to restore sinus rhythm. RESULTS: At baseline, 54 patients were in sinus rhythm and underwent pulmonary vein isolation. For patients in atrial fibrillation, after pulmonary vein isolation and ablation of additional lines, if needed, 18 patients were converted to atrial tachycardia and one directly to sinus rhythm; 96 were still in atrial fibrillation and underwent direct-current cardioversion. After a mean follow-up of 17±6 months, 57 patients (36%) experienced atrial arrhythmia recurrence. No deaths, tamponades or phrenic nerve injuries were observed following the procedure. The main mode of arrhythmia recurrence was atrial fibrillation in 75% of cases and atrial tachycardia in 25% of cases. CONCLUSION: A single-catheter approach, including pulmonary vein isolation and atrial lines, is feasible and safe in patients undergoing persistent atrial fibrillation ablation, with an acceptable success rate of 64% at mid-term follow-up.

Leadless pacemakers in critically ill patients requiring prolonged cardiac pacing: A multicenter international study.

BACKGROUND: Temporary transvenous pacing in critically ill patients requiring prolonged cardiac pacing is associated with a high risk of complications. We sought to evaluate the safety and efficacy of self-contained intracardiac leadless pacemaker (LPM) implantation in this population. METHODS AND RESULTS: Consecutive patients implanted with a Micra LPM during the hospitalization in an intensive care unit were retrospectively included. Inclusion criteria were: more than or equal to 1 supracaval central venous line, or a ventilation tube, or intravenous antibiotic therapy for ongoing sepsis or bacteremia. Patients with a history of the previous implantation of a pacemaker were excluded. Out of 1016 patients implanted with an LPM, 99 met the inclusion criteria. Mean age was 75 years and Charlson comorbidity index 7. LPM implantation was successfully performed in 98% of cases, with a perioperative complication rate of 5%, mainly cardiac injuries. In-hospital mortality rate was 6%. No late (>30 days) device-related complication occurred, especially no infection. CONCLUSIONS: LPM appears as an acceptable alternative to conventional temporary transvenous pacing in selected critically ill patients requiring prolonged cardiac pacing, especially regarding the risk of infection.

Definition of success criteria for ablation of typical right atrial flutter with a single-catheter approach: A pilot study.

BACKGROUND: The success rate of cavotricuspid isthmus ablation to treat right common flutter is high (up to 95%), but needs bidirectional block confirmation, requiring two or three catheters. AIM: To describe a new pacing technique using a single catheter to ablate and confirm cavotricuspid isthmus block with differential PR interval measurements. METHODS: We included 61 patients from five centres, who were referred for cavotricuspid isthmus ablation. All patients had cavotricuspid isthmus ablation, and the cavotricuspid isthmus block was confirmed by differential pacing using two or three catheters. The new method consisted of measuring the PR interval on the surface electrocardiogram using pacing from the tip of the ablation catheter on the lateral side (lateral delay) and the septal side (coronary sinus ostium) of the cavotricuspid isthmus line (difference=delta PR interval), before and after cavotricuspid isthmus ablation. We analysed the value of the delta PR interval in predicting bidirectional cavotricuspid isthmus block as confirmed by standard methods. RESULTS: Among our patient population (mean age 63±12 years), 39 patients were ablated during sinus rhythm, and 22 during common flutter. Cavotricuspid isthmus block was achieved in all patients but one. Lateral delay and delta PR interval increased significantly after validation of cavotricuspid isthmus block (257±42 vs. 318±50ms and 32±23 vs. 96±22ms, respectively; P<0.0001). A delta PR interval cut-off of ≥70ms had 100% sensitivity and specificity to predict bidirectional cavotricuspid isthmus block. CONCLUSIONS: A single-catheter ablation approach to performing cavotricuspid isthmus line based on surface electrocardiogram PR interval measurement is feasible. After ablation, cavotricuspid isthmus block was systematically obtained when the delta PR interval was>70ms.

History of thyroid disorders in relation to clinical outcomes in atrial fibrillation.

BACKGROUND: Atrial fibrillation is the most common cardiac complication of hyperthyroidism. The association between history of hyperthyroidism and stroke remains unclear. We sought to determine whether history of thyroid dysfunction is a thromboembolic risk factor in patients with atrial fibrillation. METHODS: Patients with atrial fibrillation seen in an academic institution between 2000 and 2010 were identified and followed-up. Clinical events (stroke/systemic embolism, bleeding, all-cause death) were recorded and related to thyroid status and disorders. Associations were examined in time-dependent models with adjustment for relevant confounders. RESULTS: Among 8962 patients, 141 patients had a history of hyperthyroidism, 540 had a history of hypothyroidism, and 8271 had no thyroid dysfunction. Mean follow-up was 929 ± 1082 days. A total of 715 strokes/systemic embolism were recorded, with no significant difference in the rates of these events in patients with a history of thyroid dysfunction vs those without thyroid problems in either univariate or multivariable analysis (hazard ratio [HR] 0.85; 95% confidence interval [CI], 0.41-1.76 for hyperthyroidism; HR 0.98; 95% CI, 0.73-1.34 for hypothyroidism). There were 791 bleeding events; history of hypothyroidism was independently related to a higher rate of bleeding events (HR 1.35; 95% CI, 1.02-1.79). No significant difference among the 3 groups was observed for the incidence of death. CONCLUSIONS: History of hyperthyroidism was not an independent risk factor for stroke/systemic embolism in atrial fibrillation, whereas hypothyroidism was associated with a higher risk of bleeding events. These data suggest no additional benefit from the inclusion of thyroid dysfunction in thromboembolic prediction models in atrial fibrillation.

Outcomes after ablation for typical atrial flutter (from the Loire Valley Atrial Fibrillation Project).

Similar predisposing factors are found in most types of atrial arrhythmias. The incidence of atrial fibrillation (AF) among patients with atrial flutter is high, suggesting similar outcomes in patients with those arrhythmias. We sought to investigate the long-term outcomes and prognostic factors of patients with AF and/or atrial flutter with contemporary management using radiofrequency ablation. In an academic institution, we retrospectively examined the clinical course of 8,962 consecutive patients admitted to our department with a diagnosis of AF and/or atrial flutter. After a median follow-up of 934 ± 1,134 days, 1,155 deaths and 715 stroke and/thromboembolic (TE) events were recorded. Patients with atrial flutter undergoing cavotricuspid isthmus ablation (n = 875, 37% with a history of AF) had a better survival rate than other patients (hazard ratio [HR] 0.35, 95% confidence interval [CI] 0.25 to 0.49, p <0.0001). Using Cox proportional hazards model and propensity score model, after adjustment for main other confounders, ablation for atrial flutter was significantly associated with a lower risk of all-cause mortality (HR 0.55, 95% CI 0.36 to 0.84, p = 0.006) and stroke and/or TE events (HR 0.53, 95% CI 0.30 to 0.92, p = 0.02). After ablation, there was no significant difference in the risk of TE between patients with a history of AF and those with atrial flutter alone (HR 0.83, 95% CI 0.41 to 1.67, p = 0.59). In conclusion, in patients with atrial tachyarrhythmias, those with atrial flutter with contemporary management who undergo cavotricuspid isthmus radiofrequency ablation independently have a lower risk of stroke and/or TE events and death of any cause, whether a history of AF is present or not.

Programming implantable cardioverter-defibrillators in primary prevention: higher or later.

Defibrillator shocks, appropriate or not, are associated with significant morbidity, as they decrease quality of life, can be involved in depression and anxiety, and are known to be proarrhythmic. Most recent data have even shown an association between shocks and overall mortality. As opposed to other defibrillator-related complications, the rate of inappropriate and unnecessary shocks can (and should) be decreased with adequate programming. This review focuses on the different programming strategies and tips available to reduce the rate of shocks in primary prevention patients with left ventricular dysfunction implanted with a defibrillator, as well as some of the manufacturers' device specificities.

Prognosis in patients hospitalized with permanent and nonpermanent atrial fibrillation in heart failure.

Atrial fibrillation (AF) and heart failure (HF) frequently coexist and are associated with an increased mortality. This study evaluated the prognosis of permanent and nonpermanent AF in patients with both AF and HF. All AF patients seen in our institution were identified and followed up. We included 1,906 patients suffering from AF and HF: 839 patients (44%) had preserved left ventricular ejection fraction (LVEF) and 1,067 patients (56%) had decreased LVEF; 1,056 patients (55%) had nonpermanent AF and 850 patients (45%) had permanent AF. During a median follow-up of 1.9 years (interquartile range 0.3 to 5.0), 377 patients died, 462 were readmitted for HF, and 200 had stroke or thromboembolic events. In patients with decreased LVEF, the rate of death was similar in patients with permanent or nonpermanent AF. In patients with preserved LVEF, permanent AF was associated with a higher risk of death and a higher risk of HF hospitalization. Stroke risk did not differ with permanent AF whatever the LVEF. NYHA functional class was an independent predictor of death (risk ratio [RR]=1.33, 95% confidence interval [CI] 1.12 to 1.59, p=0.001), as was permanent AF (RR=1.79, 95%CI 1.32 to 2.42, p=0.0002). Permanent AF (RR=1.52, 95% CI 1.20 to 1.93, p=0.0006) was also an independent predictor of readmission for HF. In conclusion, in patients with AF and HF, the risk of admission for HF and risk of death were higher when AF was permanent, particularly in patients with preserved LVEF. Stroke risk did not differ according to the pattern of AF, whatever the LVEF.

Antiplatelet therapy strategies after percutaneous coronary intervention in patients needing oral anticoagulation.

Long-term oral anticoagulant (OAC) and dual-antiplatelet therapy are commonly needed in patients with atrial fibrillation and in patients undergoing percutaneous coronary intervention (PCI), respectively. The combination of atrial fibrillation and PCI is frequent, and leads to a dilemma for antithrombotic therapy, where risk of stroke or stent thrombosis must be balanced with bleeding risk. In the WOEST study, 573 patients on OAC undergoing PCI were randomly assigned to receive clopidogrel alone or clopidogrel plus aspirin. The primary end point was the occurrence of any bleeding episode during 1-year follow-up. Clopidogrel alone administered to patients taking OAC after PCI was associated with a significantly lower rate of bleeding complications than clopidogrel plus aspirin. Moreover, a composite secondary end point of death, myocardial infarction and stent thrombosis was significantly lower in the dual-therapy group compared with the triple-therapy group. In spite of its limitations, the WOEST study constitutes a major breakthrough, showing that long-term aspirin after PCI may be obsolete in certain circumstances. This needs to be confirmed in further studies.