Entrapment of "PV-Tracker" guidewire in the pulmonary veins during atrial fibrillation ablation with PVAC Gold.

We report the entrapment of Pulmonary Vein Ablation Catheter (Medtronic, Minneapolis, MN, USA) and its guidewire within the right pulmonary veins in two patients. The catheters could be retrieved without complications but they were disabled in both cases. This nondescribed incident should be recognized by PVAC users since it may be a source of potential severe complications during pulmonary vein isolation procedures.

Ivabradine for controlling heart rate in permanent atrial fibrillation: A translational clinical trial.

BACKGROUND: Pharmacological options for rate control in atrial fibrillation are scarce. Ivabradine was postulated to reduce the ventricular rate in this setting. OBJECTIVES: The objectives of this study were to evaluate the mechanism of inhibition of atrioventricular conduction produced by ivabradine and to determine its efficacy and safety in atrial fibrillation. METHODS: The effects of ivabradine on atrioventricular node and ventricular cells were studied by in vitro whole-cell patch-clamp experiments and mathematical simulation of human action potentials. In parallel, a multicenter, randomized, open-label, phase III clinical trial compared ivabradine with digoxin for uncontrolled permanent atrial fibrillation despite ß-blocker or calcium channel blocker treatment. RESULTS: Ivabradine 1 µM inhibited "funny" current and rapidly activating delayed rectifier potassium channel current by 28.9% and 22.8%, respectively (P < .05). The sodium channel current and L-type calcium channel current were reduced only at 10 µM. Ivabradine slowed the firing frequency of a modeled human atrioventricular node action potential by 10.6% and induced a minimal prolongation of ventricular action potential. Thirty-five (51.5%) patients were randomized to ivabradine and 33 (49.5%) to digoxin. The mean daytime heart rate decreased by 11.6 beats/min (-11.5%) in the ivabradine arm (P = .02) vs 19.6 (-20.6%) in the digoxin arm (P < .001), although the noninferiority margin of efficacy was not met (Z = -1.95; P = .97). The primary safety end point occurred in 3 patients (8.6%) on ivabradine and in 8 (24.2%) on digoxin (P = .10). CONCLUSION: Ivabradine produced a moderate rate reduction in patients with permanent atrial fibrillation. The inhibition of funny current in the atrioventricular node seems to be the main mechanism responsible for this reduction. Compared with digoxin, ivabradine was less effective, was better tolerated, and had a similar rate of serious adverse events.

Adverse Clinical Outcomes and Associated Predictors in Rivaroxaban-Treated Atrial Fibrillation Patients With Renal Impairment.

Renal impairment confers worse prognosis in patients with atrial fibrillation (AF) but there is scarce evidence about the influence of direct-acting oral anticoagulants in routine clinical practice. Herein, we compared clinical outcomes between patients with AF with and without renal impairment on rivaroxaban and investigated predictors for clinical outcomes in patients with AF with renal impairment. This was a multicenter study including patients with AF on rivaroxaban for at least 6 months. During 2.5 years follow-up, ischemic strokes (IS)/transient ischemic attacks (TIA)/systemic embolisms (SE)/myocardial infarctions (MI), major bleeding, and major adverse cardiovascular events (MACE) were recorded. Creatinine clearance (CrCl) was estimated using the Cockroft-Gault equation, renal impairment was defined as a CrCl <60 ml/min, and 1,433 patients (34.8% with CrCl <60 ml/min) were included. Patients with CrCl <60 ml/min showed higher event rates for major bleeding (1.87%/year vs 0.62%/year; p = 0.003) and MACE (1.97%/year vs 0.62%/year; p = 0.002) but similar event rates for IS/TIA/SE/MI (0.66%/year vs 0.67%/year; p = 0.955). In patients with renal impairment, CHA2DS2-VASc was associated with higher risk of IS/TIA/SE/MI; HAS-BLED and any dependency level were associated with higher risk of major bleeding; and male gender and heart failure were associated with higher risk of MACE. Antiplatelets were independently associated with increased risk of IS/TIA/SE/MI and MACE. In conclusion, in patients with AF on rivaroxaban, the incidence of IS/TIA/SE/MI did not increase in those with renal impairment, suggesting that rivaroxaban may be an effective option in this subgroup. In patients with AF, male gender, heart failure, dependency, antiplatelets, CHA2DS2-VASc, and HAS-BLED were associated with increased risk of adverse outcomes.

Ivabradine for chronic heart rate control in persistent atrial fibrillation. Design of the BRAKE-AF project.

INTRODUCTION AND OBJECTIVES: Ivabradine is an inhibitor of the If channel, the main determinant of the pacemaker function of the sinus node. The drug has been approved for the treatment of angina and heart failure. There is some evidence of its role as an inhibitor of atrial-ventricular node (AVN) conduction. The aim of the BRAKE-AF project is to assess ivabradine use for rate control in atrial fibrillation (AF). METHODS: A multicenter, randomized, parallel, open-label, noninferiority phase III clinical trial will be conducted to compare ivabradine vs digoxin in 232 patients with uncontrolled permanent AF despite beta-blockers or calcium channel blockers. The primary efficacy endpoint is the reduction in daytime heart rate measured by 24-hour Holter monitoring at 3 months. This clinical trial will be supported by an electrophysiological study of the effect of ivabradine on the action potential of the human AVN. To do this, an experimental model will be used with Chinese hamster ovarium cells transfected with the DNA encoding the expression of the t channels involved in this action potential and recording of the ionic currents with patch clamp techniques. RESULTS: New data will be obtained on the effect of ivabradine on the human AVN and its safety and efficacy in patients with permanent AF. CONCLUSIONS: The results of the BRAKE-AF project might allow inclusion of ivabradine within the limited arsenal of drugs currently available for rate control in AF. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Identifier: NCT03718273.