Antoine Da Costa

Automatic Cardiac Event Recorders Reveal Paroxysmal Atrial Fibrillation after Unexplained Strokes or Transient Ischemic Attacks

Background: The etiology of stroke or transitory ischemic attack (TIA) remains frequently unknown. While paroxysmal atrial fibrillation (PAF) is often suspected, its presence remains difficult to establish. Therefore, we investigated the occurrence of PAF episodes in such a population using a long‐term automatic cardiac event recorder.

The MOnitoring Resynchronization dEvices and CARdiac patiEnts (MORE-CARE) Randomized Controlled Trial: Phase 1 Results on Dynamics of Early Intervention With Remote Monitoring

Background Remote monitoring (RM) in patients with advanced heart failure and cardiac resynchronization therapy defibrillators (CRT-D) may reduce delays in clinical decisions by transmitting automatic alerts. However, this strategy has never been tested specifically in this patient population, with alerts for lung fluid overload, and in a European setting. Objective The main objective of Phase 1 (presented here) is to evaluate if RM strategy is able to reduce time from device-detected events to clinical decisions. Methods In this multicenter randomized controlled trial, patients with moderate to severe heart failure implanted with CRT-D devices were randomized to a Remote group (with remote follow-up and wireless automatic alerts) or to a Control group (with standard follow-up without alerts). The primary endpoint of Phase 1 was the delay between an alert event and clinical decisions related to the event in the first 154 enrolled patients followed for 1 year. Results The median delay from device-detected events to clinical decisions was considerably shorter in the Remote group compared to the Control group: 2 (25th-75th percentile, 1-4) days vs 29 (25th-75th percentile, 3-51) days respectively, P=.004. In-hospital visits were reduced in the Remote group (2.0 visits/patient/year vs 3.2 visits/patient/year in the Control group, 37.5% relative reduction, P<.001). Automatic alerts were successfully transmitted in 93% of events occurring outside the hospital in the Remote group. The annual rate of all-cause hospitalizations per patient did not differ between the two groups (P=.65). Conclusions RM in CRT-D patients with advanced heart failure allows physicians to promptly react to clinically relevant automatic alerts and significantly reduces the burden of in-hospital visits. Trial Registration Clinicaltrials.gov NCT00885677; http://clinicaltrials.gov/show/NCT00885677 (Archived by WebCite at http://www.webcitation.org/6IkcCJ7NF).

Incidence of sudden cardiac death after ventricular fibrillation complicating acute myocardial infarction: a 5-year cause-of-death analysis of the FAST-MI 2005 registry

AIMSnLimited data are available on long-term prognosis or causes-of-death analysis among survivors of acute myocardial infarction (MI) according to whether or not they developed ventricular fibrillation (VF) during the acute stage of MI.nnnMETHODS AND RESULTSnAmong 3670 MI patients hospitalized in France in 2005 and enrolled in this prospective follow-up cohort study, we assessed in-hospital mortality and 5-year cause of death among those who survived to hospital discharge, according to whether they developed VF (116 cases) or not, during the acute stage. 94.5% of patients had complete follow-up at 5 years. In-hospital mortality was significantly higher among VF patients (adjusted OR 7.38, 95% CI 4.27-12.75, P < 0.001). Among 3463 survivors at hospital discharge, 1024 died during a mean follow-up of 52 ± 2 months. The overall survival rate at 5 years was 74.4% (95% CI 72.8-76.0). In Cox multivariate analysis, occurrence of VF during the acute phase of MI was not associated with an increased mortality at 5 years (HR 0.78, 95% CI 0.38-1.58, P = 0.21). The distribution of causes of death at 5 years did not statistically differ according to the presence or absence of VF, especially for sudden cardiac death (13.1% in VF group vs.12.9% in non-VF group), despite a very low rate of implantation of cardioverter defibrillator in both groups (Overall rate 1.2%).nnnCONCLUSIONnPatients developing VF in the setting of acute MI are at higher risk of in-hospital mortality. However, VF is not associated with a higher long-term all-cause or sudden cardiac death mortality.

Effects of remote monitoring on clinical outcomes and use of healthcare resources in heart failure patients with biventricular defibrillators: results of the MORE‐CARE multicentre randomized controlled trial

The aim of this study was to evaluate the clinical efficacy and safety of remote monitoring in patients with heart failure implanted with a biventricular defibrillator (CRT‐D) with advanced diagnostics.

The MOnitoring Resynchronization dEvices and CARdiac patiEnts (MORE-CARE) study: Rationale and design

BACKGROUNDnWith the advent of remote monitoring, current models of implantable cardioverter defibrillators (ICDs) have the possibility of sending automatic alert messages that allow early diagnosis of events such as lung fluid overload, atrial fibrillation and device integrity issues. Timely treatment of these events has the potential to improve patient outcome, but this has not as yet been proven.nnnMETHODSnThe MORE-CARE study is a multicenter randomized controlled trial evaluating the efficacy of advanced device diagnostics and remote monitoring in improving the outcome of patients with biventricular ICDs. Up to 1720 patients with a standard indication for a biventricular ICD will be randomized to standard in-office follow-up, or to a remote monitoring strategy using the CareLink network and involving automatic alerts for lung fluid overload, atrial fibrillation, and device integrity issues. The first phase aims at evaluating the delay between an alert event, and clinical action to the event. The second phase of the study will evaluate whether the remote monitoring strategy results in a significant reduction of a combined end point of total mortality or cardiovascular and device-related hospitalization. The duration of the study will be event-driven due to its sequential design.nnnCONCLUSIONnMORE-CARE will evaluate the efficacy of remote monitoring for improving patient outcome in patients implanted with a biventricular ICD.

Anatomical factors involved in difficult cardiac resynchronization therapy procedure: a non-invasive study using dual-source 64-multi-slice computed tomography.

AIMSnIn cardiac resynchronization therapy (CRT) procedure, left ventricular (LV) lead implantation is time consuming. In this clinical setting, no study has investigated the impact of right atrium anatomical parameters on both CRT implantation procedure duration and X-ray exposure. Additionally, only few studies have examined the coronary sinus (CS) using dual-source 64-multi-slice computed tomography (DS 64-MSCT), and its impact on CRT procedure parameters has not yet been investigated. The aim of this prospective study was to identify local anatomical predictive factors of difficult CRT implantation procedure using DS 64-MSCT.nnnMETHODS AND RESULTSnBetween January and July 2010, 50 consecutive patients underwent primo CRT implantation. The patient population had a mean age of 70 ± 10 years, and was 34% female, with New York Heart Association Class 3.2 ± 0.3 heart failure, left ventricle ejection fraction 30 ± 4%, and QRS width 157 ± 30 ms. Cardiac resynchronization therapy implantation was attempted in 50 patients, and first LV lead implantation was obtained in 49 of 50 patients (98% primary success). One implantation failed (2%) due to unsuccessful LV lead implant. Procedure parameters were as follows: LV threshold, 1.4 ± 0.8 V; LV wave amplitude, 17 ± 8 mV; LV impedance, 830 ± 240 Ω; median procedure time (skin to skin), 51 min (38 min); median fluoroscopy procedure time, 11.9 min (22 min); and median LV fluoroscopic time, 10.3 min (22 min). In 10 patients (20%), procedures were difficult requiring an implantation lasting ≥ 85 min. The only predictive factor for difficult CRT implantation was the insertion level of the CS ostium (CSO), evaluated by the distance between the CSO and the bottom floor of the right atrium (14.8 ± 4 vs. 9.5 ± 4; P= 0.01). Neither the right atrium dilation nor right ventricular dysfunction was associated with difficult CRT implantation procedures.nnnCONCLUSIONSnToday, despite improvements in the materials used, problems still remain in the CRT procedure. In this clinical setting, the only predictive factor for very long CRT procedures is the CSO-level insertion (located high). This anatomical anomaly identified by DS 64-MSCT prior to surgery is responsible for 20% of difficult CRT device implantation procedures.

Heart rate variability before ventricular arrhythmias in patients with coronary artery disease and an implantable cardioverter defibrillator.

Background: Changes in autonomic regulation of the heart may be responsible for the occurrence of arrhythmias. Although a decrease in 24‐hour heart rate variability is a strong predictor of subsequent arrhythmias in patients with heart disease, many questions remain unanswered concerning changes in heart rate and heart rate variability in the minutes or hours preceding an arrhythmia. The aim of our study was to analyze changes in heart rate and heart rate variability occurring during the 90 minutes preceding an arrhythmia, in patients with coronary heart disease and an implantable defibrillator.

Catheter selection for ablation of the cavotricuspid isthmus for treatment of typical atrial flutter

Radiofrequency catheter ablation (RFA) represents the first line therapy of the cavotricuspid isthmus-dependent atrial flutter (CTI-AFL) with a high efficacy and low secondary effects. RFA of CTI-dependent AFL can be performed by using various types of ablation catheters. Recent evaluations comparing externally cooled tip RFA (ecRFA) catheters and large-tip (8xa0mm) catheters have revealed that these catheters have a higher efficacy for CTI-AFL ablation compared to 4-mm catheters. The reliability of RFA catheters for AFL is variable and an optimal catheter selection may enhance the RFA effectiveness. The main goal of this article is to review the elements that improve the management of CTI RFA. Preliminary examinations of histopathologic and anatomical elements that may interfere with conventional CTI RFA are presented. Experimental studies concerning the electrobiology of large-tip and cooled-tip catheters are compared. The different catheter designs between cooled-tip and 8-mm-tip catheters are examined (size of the deflectable curve, rotation stability, and size of the distal nonsteerable catheter part) because of their critical role in CTI RFA results. A thorough review of clinical trials of each catheter is presented, and comparison of both catheters in this clinical setting is analyzed. In addition, the role of CTI morphology on AFL RF duration is underlined such as the value of right atrial angiography as an adjunct tool for CTI RFA catheter selection. Based on randomized studies, 8-mm-tip catheters seem to be more effective for ablation in case of straight angiographic isthmus morphology. On the other hand, ecRFA catheters appear to be more effective in cases of complex CTI anatomy or difficult CTI RFA. To reduce X-ray exposition and RFA application time, few studies report that CTI angiographic evaluation before RFA allows a catheter selection based on both CTI morphology and length. Moreover, preliminary data of randomized studies showed that an angiographic isthmus evaluation may predict both the effectiveness of a RFA catheter and the risk of an expensive catheter crossover.

Transcatheter leadless cardiac pacing: The new alternative solution

INTRODUCTIONnA lack of information about the feasibility and safety of leadless pacemaker (LPMs) exists in a fragile population of patients with limited venous anatomy access or conventional pacemaker (PM) contraindication. Accordingly, the goal of this prospective observational study was to report our experience with this new leadless technology in a subset of patients with contraindication or limited venous access.nnnMETHODS AND RESULTSnBetween May 2015 and July 2016, 14 patients were consecutively included. The indications for initial PM implantation were atrioventricular (AV) block in 10/14 patients (71%), bradyarrhythmia in one (7%), and uncontrolled atrial fibrillation (AFib) requiring AV-node ablation in three (21.5%). AFib was observed in 9 of the 14 patients (64.3%) and 3 were completely dependent with no escape rhythm (21.5%). Normal access pathways via the right or left subclavian veins were occluded due to previous PM implantations and revisions in 4 patients (28.6%) and total vena cava occlusion in 3 (21.4%). End-stage renal disease with hemodialysis was present in 8 (57%) with either local-device infections or presence of long-term implanted dialysis catheters. Evidence of previous bilaterally-infected pectoral tissue was present in 3 patients (21.5%). All procedures were successful (100%) and electrical parameters remained stable over time. No direct pacemaker-related adverse events were reported, including mechanical complications, except for one ventricular fibrillation one day post-implantation under very specific conditions.nnnCONCLUSIONnThis series demonstrated very stable performance and reassuring safety results during mid-term follow-up in a very fragile population requiring a PM. The Micra LPM constitutes an excellent alternative to the epicardial surgical approach in this very fragile population.

Radiofrequency Catheter Selection Based on Cavotricuspid Angiography Compared with a Control Group with an Externally Cooled-Tip Catheter: A Randomized Pilot Study

Background: Radiofrequency ablation (RFA) of cavotricuspid isthmus (CTI)‐dependent atrial flutter (AFL) can be performed using either externally cooled‐tip RFA catheters or large‐tip (8 mm) catheters. However, experimental and clinical studies suggest that the efficacy of both catheters may vary with CTI anatomy and catheters orientation.