Giovanni B. Forleo

Periprocedural Stroke and Bleeding Complications in Patients Undergoing Catheter Ablation of Atrial Fibrillation With Different Anticoagulation Management Results From the Role of Coumadin in Preventing Thromboembolism in Atrial Fibrillation (AF) Patients Undergoing Catheter Ablation (COMPARE) Randomized Trial

Background— Periprocedural thromboembolic and hemorrhagic events are worrisome complications of catheter ablation for atrial fibrillation (AF). The periprocedural anticoagulation management could play a role in the incidence of these complications. Although ablation procedures performed without warfarin discontinuation seem to be associated with lower thromboembolic risk, no randomized study exists. Methods and Results— This was a prospective, open-label, randomized, parallel-group, multicenter study assessing the role of continuous warfarin therapy in preventing periprocedural thromboembolic and hemorrhagic events after radiofrequency catheter ablation. Patients with CHADS2 score ≥1 were included. Patients were randomly assigned in a 1:1 ratio to the off-warfarin or on-warfarin arm. The incidence of thromboembolic events in the 48 hours after ablation was the primary end point of the study. The study enrolled 1584 patients: 790 assigned to discontinue warfarin (group 1) and 794 assigned to continuous warfarin (group 2). No statistical difference in baseline characteristics was observed. There were 39 thromboembolic events (3.7% strokes [n=29] and 1.3% transient ischemic attacks [n=10]) in group 1: two events (0.87%) in patients with paroxysmal AF, 4 (2.3%) in patients with persistent AF, and 33 (8.5%) in patients with long-standing persistent AF. Only 2 strokes (0.25%) in patients with long-standing persistent AF were observed in group 2 (P<0.001). Warfarin discontinuation emerged as a strong predictor of periprocedural thromboembolism (odds ratio, 13; 95% confidence interval, 3.1–55.6; P<0.001). Conclusion— This is the first randomized study showing that performing catheter ablation of AF without warfarin discontinuation reduces the occurrence of periprocedural stroke and minor bleeding complications compared with bridging with low-molecular-weight heparin. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01006876.

Periprocedural Stroke and Bleeding Complications in Patients undergoing Catheter Ablation of Atrial Fibrillation with Different Anticoagulation Management: Results from the "COMPARE" Randomized Trial

Background— Periprocedural thromboembolic and hemorrhagic events are worrisome complications of catheter ablation for atrial fibrillation (AF). The periprocedural anticoagulation management could play a role in the incidence of these complications. Although ablation procedures performed without warfarin discontinuation seem to be associated with lower thromboembolic risk, no randomized study exists. Methods and Results— This was a prospective, open-label, randomized, parallel-group, multicenter study assessing the role of continuous warfarin therapy in preventing periprocedural thromboembolic and hemorrhagic events after radiofrequency catheter ablation. Patients with CHADS2 score ≥1 were included. Patients were randomly assigned in a 1:1 ratio to the off-warfarin or on-warfarin arm. The incidence of thromboembolic events in the 48 hours after ablation was the primary end point of the study. The study enrolled 1584 patients: 790 assigned to discontinue warfarin (group 1) and 794 assigned to continuous warfarin (group 2). No statistical difference in baseline characteristics was observed. There were 39 thromboembolic events (3.7% strokes [n=29] and 1.3% transient ischemic attacks [n=10]) in group 1: two events (0.87%) in patients with paroxysmal AF, 4 (2.3%) in patients with persistent AF, and 33 (8.5%) in patients with long-standing persistent AF. Only 2 strokes (0.25%) in patients with long-standing persistent AF were observed in group 2 (P<0.001). Warfarin discontinuation emerged as a strong predictor of periprocedural thromboembolism (odds ratio, 13; 95% confidence interval, 3.1–55.6; P<0.001). Conclusion— This is the first randomized study showing that performing catheter ablation of AF without warfarin discontinuation reduces the occurrence of periprocedural stroke and minor bleeding complications compared with bridging with low-molecular-weight heparin. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01006876.

Ablation Versus Amiodarone for Treatment of Persistent Atrial Fibrillation in Patients With Congestive Heart Failure and an Implanted Device: Results From the AATAC Multicenter Randomized Trial

Background— Whether catheter ablation (CA) is superior to amiodarone (AMIO) for the treatment of persistent atrial fibrillation (AF) in patients with heart failure is unknown. Methods and Results— This was an open-label, randomized, parallel-group, multicenter study. Patients with persistent AF, dual-chamber implantable cardioverter defibrillator or cardiac resynchronization therapy defibrillator, New York Heart Association II to III, and left ventricular ejection fraction <40% within the past 6 months were randomly assigned (1:1 ratio) to undergo CA for AF (group 1, n=102) or receive AMIO (group 2, n=101). Recurrence of AF was the primary end point. All-cause mortality and unplanned hospitalization were the secondary end points. Patients were followed up for a minimum of 24 months. At the end of follow-up, 71 (70%; 95% confidence interval, 60%–78%) patients in group 1 were recurrence free after an average of 1.4±0.6 procedures in comparison with 34 (34%; 95% confidence interval, 25%–44%) in group 2 (log-rank P<0.001). The success rate of CA in the different centers after a single procedure ranged from 29% to 61%. After adjusting for covariates in the multivariable model, AMIO therapy was found to be significantly more likely to fail (hazard ratio, 2.5; 95% confidence interval, 1.5–4.3; P<0.001) than CA. Over the 2-year follow-up, the unplanned hospitalization rate was (32 [31%] in group 1 and 58 [57%] in group 2; P<0.001), showing 45% relative risk reduction (relative risk, 0.55; 95% confidence interval, 0.39–0.76). A significantly lower mortality was observed in CA (8 [8%] versus AMIO (18 [18%]; P=0.037). Conclusions— This multicenter randomized study shows that CA of AF is superior to AMIO in achieving freedom from AF at long-term follow-up and reducing unplanned hospitalization and mortality in patients with heart failure and persistent AF. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00729911.

Catheter ablation of atrial fibrillation in patients with diabetes mellitus type 2: results from a randomized study comparing pulmonary vein isolation versus antiarrhythmic drug therapy.

Introduction: Atrial fibrillation (AF) and diabetes mellitus type 2 (DM2) often coexist; however, a small number of patients with DM2 undergoing catheter ablation (CA) of AF have been included in previous studies. The aim of this study was to evaluate safety and efficacy of ablation therapy in DM2 patients with drug refractory AF.

Left ventricular pacing with a new quadripolar transvenous lead for CRT: Early results of a prospective comparison with conventional implant outcomes

BACKGROUND Flexible left ventricular (LV) pacing configurations are a useful component of cardiac resynchronization therapy (CRT) systems for preventing high LV pacing thresholds and phrenic nerve stimulation (PNS). A quadripolar LV lead has recently been designed with the purpose of allowing more choices in lead placement location and programming capability. OBJECTIVE To verify the effectiveness of quadripolar LV leads compared to conventional bipolar LV leads implant outcomes. METHODS Forty-five consecutive patients underwent implantation with either the quadripolar (n = 22; quadripolar group) or a conventional bipolar LV lead (n = 23; bipolar group). The primary outcome of the study was LV lead failure, defined as the need for lead revision or reprogramming during the first 3 months after implantation. Additionally, operative and follow-up data were prospectively noted and checked for significance between groups. RESULTS The implantation success rate in both groups was 100%. Baseline characteristics, procedure duration, and fluoroscopy time did not differ significantly between groups. Two lead dislodgments (requiring reoperation) and 4 clinical PNS were reported in the bipolar group; reprogramming of the device was sufficient to prevent PNS in 3 patients, the fourth is pending solution. One PNS successfully managed noninvasively occurred in the quadripolar group. By Kaplan-Meier analysis, event-free survival for the combined primary outcome was significantly lower in patients with quadripolar leads (P = .037). CONCLUSION This prospective, controlled study provides strong evidence that CRT with the quadripolar LV lead results in low rates of dislocations and phrenic nerve stimulation.

Clinical and procedural outcome of patients implanted with a quadripolar left ventricular lead: Early results of a prospective multicenter study

BACKGROUND Recent studies suggest that cardiac resynchronization therapy (CRT) with a quadripolar left ventricular (LV) lead results in low rates of dislocation and phrenic nerve stimulation (PNS) acutely and at short-term follow-up. Confirmation of these results by long-term observational studies is needed. OBJECTIVE To evaluate the long-term procedural and clinical outcomes of CRT patients implanted with a quadripolar LV lead. METHODS A total of 154 consecutive heart failure patients (79% men, age 68 ± 10 years) having CRT implantation attempts with a quadripolar LV lead were included in this observational registry. Demographic and clinical data were preoperatively collected, and patients were followed up for at least 6 months. RESULTS The overall implant success rate after coronary sinus cannulation was 97.4%. Mean overall duration and fluoroscopy time of successful procedures was 112 ± 22 and 16 ± 8 minutes, respectively, while 17 ± 13 minutes were necessary for the LV lead placement. After implant, the conventional bipolar configuration was used as the final pacing configuration in 33.3% of the patients. Four lead dislodgments (requiring reoperation) and 9 clinical PNS were reported during follow-up; reprogramming of the device was sufficient to prevent PNS in all patients. Once placed, the LV lead remained stable with excellent pacing thresholds during follow-up (15 ± 5 months). Overall, there were 71.3% CRT responders as assessed by 6-month echocardiography, and 66% improved at least 1 New York Heart Association class. CONCLUSION Over the longer term, CRT with the quadripolar LV lead is associated with excellent pacing thresholds, low rates of dislocations, and PNS.

Safety and efficacy of a new magnetic resonance imaging-compatible pacing system: early results of a prospective comparison with conventional dual-chamber implant outcomes.

BACKGROUND A new pacing system has been designed and tested preclinically for safe use in the magnetic resonance imaging (MRI) environment. Experience with this innovative system has not yet been reported. OBJECTIVE The purpose of this study was to verify the safety and effectiveness of this newly designed system compared to conventional DDD implant outcomes. METHODS Over an 11-month period, 107 consecutive patients (71 men and 36 women; age 72.6 +/- 8.5 years) were implanted with either the MRI system (n = 50; MRI group) or a dual-chamber, active-fixation lead (Medtronic 4076) non-MRI system (n = 57; DDD group). Data were collected at implant and during postoperative follow-up at 1, 3, 6, and 12 months. Procedural and fluoroscopic times at implant, as well as lead measurements, handling characteristics, and procedural-related complications, were prospectively analyzed. RESULTS The implantation success rate in both groups was 100%. Cephalic access was 63% for MRI patients and 70% for DDD patients (P = NS). Follow-up was obtained for all patients (median 6.8 months, range 3-12 months). At implant and at the end of follow-up, stimulation thresholds, sensing, and impedance were acceptable. No cases of high pacing thresholds or inadequate sensing were noted. No complications occurred, and no patient experienced subsequent lead displacement. CONCLUSION This prospective, controlled study provides strong evidence that the feasibility and safety of this novel technology compare favorably with those of the conventional technique.

Initial experience with the Mesh catheter for pulmonary vein isolation in patients with paroxysmal atrial fibrillation

BACKGROUND A novel catheter design (HD Mesh ablator, Bard) combining high-density circumferential mapping and direct radiofrequency (RF) energy delivery has been developed to map and isolate the pulmonary veins (PVs). OBJECTIVE The purpose of this study was to assess the feasibility of the Mesh catheter for PV isolation in patients with paroxysmal atrial fibrillation (AF). METHODS Twenty consecutive patients (mean age 56.4 +/- 12.2 years; 16 men) with paroxysmal drug-refractory AF were referred for ablation. The procedure was performed in a stepwise manner: PV isolation was initially attempted with the Mesh ablator, and if that was not successful, a conventional ablation approach was then used. RESULTS A total of 73 PVs including seven veins with left common ostium were targeted. Successful deployment of the Mesh was achieved in all but four veins (94.5%). Using the Mesh catheter for ablation, PV isolation was achieved in 46 (63%) of the 73 PVs. The mean (RF) ablation time required to achieve complete isolation was 12.4 +/- 6.1 minutes per PV. The Mesh-only approach allowed isolation of all veins in eight (40%) patients. In combination with conventional ablation, successful PV isolation was achieved in 71 (97%) of 73 PVs. No complications attributable to the Mesh ablator occurred in this series. CONCLUSIONS PV isolation using the Mesh catheter is feasible and may simplify the current PV isolation procedures. With the current catheter design, PV isolation could be achieved in 63% of PVs. A larger Mesh diameter with an over-the-wire design may help improve the acute success rate.

Results From a Single-Blind, Randomized Study Comparing the Impact of Different Ablation Approaches on Long-Term Procedure Outcome in Coexistent Atrial Fibrillation and Flutter (APPROVAL)

Background— This study examined the impact of different ablation strategies on atrial fibrillation (AF) recurrence and quality of life in coexistent AF and atrial flutter (AFL). Methods and Results— Three-hundred sixty enrolled patients with documented AF and AFL were blinded and randomized to group 1, AF±AFL ablation (n=182), or group 2, AFL ablation only (n=178). AF recurrence was evaluated with event recording and 7-day Holter at 3, 6, 9, and 12-month follow-ups. Quality of life was assessed at baseline and at the 12-month follow-up with 4 questionnaires: the Medical Outcome Study Short Form, the Hospital Anxiety and Depression Score, the Beck Depression Inventory, and the State-Trait Anxiety Inventory. Of the 182 patients in group 1, 58 (age, 63±8 years; 78% male; left ventricular ejection fraction, 59±8%) had AF+AFL ablation and 124 (age, 61±11 years; 72% male; left ventricular ejection fraction, 59±7%) had AF ablation only. In group 2 (age, 62±9 years; 76% male; left ventricular ejection fraction, 58±10%), only AFL was ablated by achieving bidirectional isthmus conduction block. Baseline characteristics were not different across groups. At 21±9 months of follow-up, 117 in group 1 (64%) and 34 in group 2 (19%) were arrhythmia free (P<0.001). In group 1, scores on most quality-of-life subscales showed significant improvement at follow-up, whereas group 2 patients derived relatively minor benefit. Conclusions— In coexistent AF and AFL, lower recurrence rate and better quality of life are associated with AF ablation only or AF+AFL ablation than with lone AFL ablation. Furthermore, quality of life directly correlates with freedom from arrhythmia, as shown in this study for the first time in patients blinded to the procedure. Clinical Trial Registration— URL: http://www.clinicaltrial.gov/. Unique identifier: NCT01439386.

Hospitalization rates and associated cost analysis of cardiac resynchronization therapy with an implantable defibrillator and quadripolar vs. bipolar left ventricular leads: a comparative effectiveness study.

Aims This study compares, from a prospective, observational, non-randomized registry, the post-implant hospitalization rates and associated healthcare resource utilization of cardiac resynchronization therapy-defibrillator (CRT-D) patients with quadripolar (QUAD) vs. bipolar (BIP) left ventricular (LV) leads. Methods and results Between January 2009 and December 2012, 193 consecutive patients receiving de novo CRT-D implants with either a QUAD (n = 116) or a BIP (n = 77) LV lead were enrolled at implant and followed until July 2013 at a single-centre, university hospital. Post-implant hospitalizations related to heart failure (HF) or LV lead surgical revision and associated payer costs were identified using ICD-9-CM diagnosis and procedure codes. Italian national reimbursement rates were determined. Propensity scores were estimated using a logistic regression model based upon 11 pre-implant baseline characteristics and were used to derive a 1 : 1 matched cohort of QUAD (n = 77) and BIP (n = 77) patients. Hospitalization rates for the two groups were compared using negative binomial regression and associated payer costs were compared using non-parametric bootstrapping (×10 000) and one-sided hypothesis test. Hospitalization rates of the QUAD group [0.15/ patient (pt)-year] were lower than those of the BIP group (0.32/ pt-year); the incidence rate ratio was 0.46, P = 0.04. The hospitalization costs for the QUAD group (434 ± 128 €/pt-year) were lower than those for the BIP group (1136 ± 362 €/pt-year). The average difference was 718 €/pt-year, P = 0.016. Conclusions In this comparative effectiveness assessment of well-matched groups of CRT-D patients with quadripolar and bipolar LV leads, QUAD patients experienced a lower rate of hospitalizations for HF and LV lead surgical revision, and a lower cost burden. This has important implications for LV pacing lead choice.