Mohamed Kanj

Atrial Fibrillation Ablation in Patients With Therapeutic International Normalized Ratio : Comparison of Strategies of Anticoagulation Management in the Periprocedural Period

Background— The best approach to management of anticoagulation before and after atrial fibrillation ablation is not known. Methods and Results— We compared outcomes in consecutive patients undergoing pulmonary vein antrum isolation for persistent atrial fibrillation. Early in our practice, warfarin was stopped 3 days before ablation, and a transesophageal echocardiogram was performed to rule out clot. Enoxaparin, initially 1 mg/kg twice daily (group 1) and then 0.5 mg/kg twice daily (group 2), was used to “bridge” patients after ablation. Subsequently, warfarin was continued to maintain the international normalized ratio between 2 and 3.5 (group 3). Minor bleeding was defined as hematoma that did not require intervention. Major bleeding was defined as either cardiac tamponade, hematoma that required intervention, or bleeding that required blood transfusion. Pulmonary vein ablation was performed in 355 patients (group 1=105, group 2=100, and group 3=150). More patients had spontaneous echocardiographic contrast in groups 1 and 2. One patient in group 1 had an ischemic stroke compared with 2 patients in group 2 and no patients in group 3. In group 1, 23 patients had minor bleeding, 9 had major bleeding, and 1 had pericardial effusion but no tamponade. In group 2, 19 patients had minor bleeding, and 2 patients developed symptomatic pericardial effusion with need for pericardiocentesis 1 week after discharge. In group 3, 8 patients developed minor bleeding, and 1 patient developed pericardial effusion with no tamponade. Conclusions— Continuation of warfarin throughout pulmonary vein ablation without administration of enoxaparin is safe and efficacious. This strategy can be an alternative to bridging with enoxaparin or heparin in the periprocedural period.

Radiofrequency ablation of atrial fibrillation under therapeutic international normalized ratio: A safe and efficacious periprocedural anticoagulation strategy

BACKGROUND The best periprocedural anticoagulation strategy at the time of pulmonary vein isolation (PVI) is not known. Most centers stop administering warfarin (Coumadin) and use bridging with heparin or enoxaparin. OBJECTIVE The purpose of this study was to evaluate the efficacy and safety of PVI under therapeutic international normalized ratio (INR). METHODS Between January 2005 and December 2008, PVI was performed in 3,052 patients with therapeutic INR (> or =1.8) at the time of ablation. All patients were evaluated for ischemic strokes and bleeding complications. RESULTS Mean INR was 2.53 +/- 0.62. Only 3 (0.098%) patients had ischemic strokes. One patient had a hemorrhagic stroke on the third day postablation but recovered completely by 1-week follow-up. Bleeding complications occurred in 34 (1.11%) patients; most were minor (0.79%). Major hemorrhagic complications occurred in 10 (0.33%) patients (tamponade in 5, hematomas requiring intervention in 2, transfusion necessary in 3). CONCLUSION In a large patient population, continuation of Coumadin at a therapeutic INR at the time of PVI without use of heparin or enoxaparin for bridging is a safe and efficacious periprocedural anticoagulation strategy. It is an acceptable and potentially better alternative to strategies that use bridging with heparin or enoxaparin.

Electrical isolation of the superior vena cava: An adjunctive strategy to pulmonary vein antrum isolation improving the outcome of AF ablation

PV isolation at the antrum (PVAI) has improved safety and efficacy of ablation procedures for atrial fibrillation (AF). AF triggers from the superior vena cava (SVC) may compromise the outcome of PVAI.

Natural History and Long-Term Outcomes of Ablated Atrial Fibrillation

Background—Atrial fibrillation (AF) ablation is increasingly used in clinical practice. We aimed to study the natural history and long-term outcomes of ablated AF. Methods and Results—We followed 831 patients after pulmonary vein isolation (PVI) performed in 2005. We documented clinical outcomes using our prospective AF registry with most recent update on this group of patients in October 2009. In the first year after ablation, 23.8% had early recurrence. Over long-term follow-up (55 months), only 8.9% had late arrhythmia recurrence defined as occurring beyond the first year after ablation. Repeat ablations in patients with late recurrence revealed conduction recovery in at least 1 of the previously isolated PVs in all of them and right-sided triggers with isoproterenol testing in 55.6%. At last follow-up, clinical improvement was 89.9% (79.4% arrhythmia-free off antiarrhythmic drugs and 10.5% with AF controlled with antiarrhythmic drugs). Only 4.6% continued to have drug-resistant AF. It was possible to safely discontinue anticoagulation in a substantial proportion of patients with no recurrence in the year after ablation (CHADS score ⩽2, stroke incidence of 0.06% per year). The procedure-related complication rate was very low. Conclusions—Pulmonary vein isolation is safe and efficacious for long-term maintenance of sinus rhythm and control of symptoms in patients with drug-resistant AF. It obviates the need for antiarrhythmic drugs, negative dromotropic agents, and anticoagulants in a substantial proportion of patients.

Clinical predictors of adverse patient outcomes in an experience of more than 5000 chronic endovascular pacemaker and defibrillator lead extractions

BACKGROUND It is difficult to predict adverse patient outcomes associated with transvenous lead extraction (TLE) procedures. OBJECTIVE The purpose of this study was to examine the safety and efficacy of chronic endovascular pacemaker and implantable cardioverter-defibrillator (ICD) lead extraction and risk factors associated with adverse patient outcomes. METHODS Consecutive patients undergoing TLE at the Cleveland Clinic between August 1996 and August 2011 were included in the analysis. Univariate and multivariable logistic regression analyses were performed to evaluate for associations with outcomes. Continuous data are given as median (25th, 75th percentile). Categorical data are given as number (percentage). RESULTS In total, 5521 leads (4137 [74.9%] pacemaker, 1384 [25.1%] ICD) were extracted during 2999 TLE procedures (patient age 67.2 [55.2, 76.2] years, 30.2% female). Lead implant duration was 4.7 (2.4, 8.3) years, and 2.0 (1.0, 2.0) leads were extracted per procedure. Powered sheaths were used in 74.9% of procedures. Overall, there was 95.1% complete procedural success, 98.9% clinical success, and 1.1% failure, with 3.6% minor complications and 1.8% major complications. All-cause mortality within 30 days of TLE was 2.2%. Multivariable predictors of major complications included cerebrovascular disease, ejection fraction ≤15%, lower platelet count, international normalized ratio ≥1.2, mechanical sheaths, and powered sheaths. Multivariable predictors of all-cause mortality within 30 days of TLE included body mass index <25 kg/m(2), end-stage renal disease, higher New York Heart Association functional class, lower hemoglobin, higher international normalized ratio, lead extraction for infection, and extraction of a dual-coil ICD lead. CONCLUSION TLE in this single-center experience was highly successful. Risk factors associated with adverse patient outcomes were identified.

Intracardiac echo-guided image integration: optimizing strategies for registration.

Introduction: Image integration is being used in ablation procedures. However, the success of this approach is dependent on the accuracy of the image integration process. This study aims to evaluate the in vivo accuracy and reliability of the integrated image.

Plasma B-Type Natriuretic Peptide Levels and Recurrent Arrhythmia After Successful Ablation of Lone Atrial Fibrillation

Background— Plasma B-type natriuretic peptide (BNP) is abnormally elevated in patients with lone atrial fibrillation (AF). The exact significance and prognostic implications of this elevation have yet to be determined. Little is known about BNP in lone AF patients undergoing arrhythmia ablation. We sought to determine the relationship between BNP levels and the risk of recurrent arrhythmia after ablation of lone AF. Methods and Results— We followed up 726 patients with lone AF undergoing first-time arrhythmia ablation. All had BNP levels measured on the day of ablation with of the point-of-care Triage Meter assay (Biosite Diagnostics, San Diego, CA). At baseline, factors associated with elevated BNP levels in multivariable linear regression analysis (with log BNP being the dependent variable) were older age (&bgr; regression coefficient for +1-year change, 0.025; P<0.0001), longer duration of AF (&bgr; for +1-year change, 0.031; P=0.01), nonparoxysmal AF (versus paroxysmal; &bgr;, 0.52; P<0.0001), and larger left atrial size (&bgr; for +1-cm2 change, 0.040; P<0.0001). The BNP levels were strongly associated with arrhythmia recurrence in univariate- (hazard ratio for +1-log-BNP change, 2.32; 95% confidence interval, 2.11 to 2.74; P<0.001) and covariate- (hazard ratio for +1-log-BNP change, 2.13; 95% confidence interval, 2.06 to 2.38; P<0.001) adjusted Cox proportional hazards analysis. The covariate-adjusted hazard ratios for recurrent arrhythmia were 1.6, 2.7, 4.3, and 5.7 for the second, third, fourth, and fifth quintiles, respectively, compared with patients in the lowest quintile (P for trend across quintiles <0.001). Conclusions— B-type natriuretic peptide levels correlate with AF burden (chronicity, altered hemodynamics, and anatomic remodeling) in patients with lone AF and are strong predictors of recurrent arrhythmia after ablation. Elevated BNP levels may reflect increased cardiac chamber wall stress and/or intrinsic atrial disease, thus increasing the risk of arrhythmia recurrence.

Electrophysiologic characteristics and catheter ablation of ventricular tachyarrhythmias among patients with heart failure on ventricular assist device support

BACKGROUND Ventricular tachyarrhythmias (VT) are common among ventricular assist device (VAD) recipients, yet electrophysiologic (EP) characteristics and catheter ablation outcomes remain uncharacterized. OBJECTIVE To evaluate the EP characteristics and catheter ablation outcomes for VTs among heart failure patients on VAD support. METHODS The Cleveland Clinic registry of consecutive patients undergoing VAD placement in 1991-2010 with medically refractory, symptomatic VT referred for EP study and catheter ablation. RESULTS Among 611 recipients of VAD (mean age 53.3 ± 12.4 years, 80% men), 21 patients (3.4%) were referred for 32 EP procedures, including 11 patients (52%) presenting with implantable cardioverter-defibrillator therapy (13 shocks, 26 antitachycardia pacing). Data from 44 inducible tachycardias (mean cycle length 339 ± 59 ms) demonstrated monomorphic VT (n = 40, 91%; superior axis 52%, right bundle branch block morphology 41%) and polymorphic ventricular tachycardia (PMVT)/ventricular fibrillation (n = 4, 8%). Electroanatomic mapping of 28 tachycardias in 20 patients demonstrated reentrant VT related to intrinsic scar (n = 21 of 28, 75%) more commonly than the apical inflow cannulation site (n = 4 of 28, 14%), focal/microreentry VT (n = 2 of 28, 7%), or bundle branch reentry (n = 1 of 28, 3.5%). Catheter ablation succeeded in 18 of 21 patients (86%). VT recurred in 7 of 21 patients (33%) at a mean of 133 ± 98 days, and 6 patients (29%) required repeat procedures, with subsequent recurrence in 4 of 21 patients (19%). CONCLUSIONS Catheter ablation of VT is effective among recipients of VAD. Intrinsic myocardial scar, rather than the apical device cannulation site, appears to be the dominant substrate.

Transvenous extraction of implantable cardioverter-defibrillator leads under advisory—A comparison of Riata, Sprint Fidelis, and non-recalled implantable cardioverter-defibrillator leads

BACKGROUND Comparative safety and efficacy associated with transvenous lead extraction (TLE) of recalled and non-recalled implantable cardioverter-defibrillator (ICD) leads has not been well characterized. OBJECTIVES To compare the indications, techniques, and procedural outcomes of recalled vs non-recalled ICD lead extraction procedures. METHODS TLE procedures performed at our institution from June 2002 to June 2012 in which Riata, Sprint Fidelis, or non-recalled ICD leads were extracted were included in the analysis. RESULTS ICD lead extraction procedures were performed in 1079 patients, including 430 patients with recalled leads (121 Riata, 308 Sprint Fidelis, and 1 Riata and Sprint Fidelis) and 649 patients with non-recalled ICD leads. A total of 2056 chronic endovascular leads were extracted, of which 1215 (59.1%) were ICD leads. Overall, there was 96.8% complete procedural success, 99.1% clinical success, and 0.9% failure, with 3.9% minor complications and 1.5% major complications. Procedural outcomes for Riata and Sprint Fidelis TLE procedures were no different. Lead implant duration was significantly less in recalled than in non-recalled ICD lead TLE procedures. Complete procedural success was higher in recalled (424 of 430 [98.6%]) than in non-recalled (621 of 649 [95.7%]; P = .007) ICD lead TLE procedures. Minor complications were lower in recalled (10 of 430 [2.3%]) than in non-recalled (32 of 649 [5.0%]; P = .030) ICD lead TLE procedures. Rates of clinical success, failure, and major complications were no different in the recalled and non-recalled ICD lead TLE procedures. CONCLUSION In our experience, recalled ICD leads were extracted with safety and efficacy comparable to that of non-recalled ICD leads.

Incidence and predictors of right ventricular pacing-induced cardiomyopathy in patients with complete atrioventricular block and preserved left ventricular systolic function

BACKGROUND Right ventricular (RV) pacing may worsen left ventricular cardiomyopathy in patients with reduced left ventricular ejection fraction (LVEF) and advanced atrioventricular block. OBJECTIVE The objectives of this study were to calculate incidence and identify predictors of RV pacing-induced cardiomyopathy (PICM) in complete heart block (CHB) with preserved LVEF and to describe outcomes of subsequent cardiac resynchronization therapy (CRT) upgrade. METHODS An analysis of consecutive patients receiving permanent pacemaker (PPM) from 2000 to 2014 for CHB with LVEF >50% was performed. PICM was defined as CRT upgrade or post-PPM LVEF ≤40%. PICM association was determined via multivariable regression analysis. CRT response was defined by LVEF increase ≥10% or left ventricular end-systolic volume decrease ≥15%. RESULTS Of the 823 study patients, 101 (12.3%) developed PICM over the mean follow-up of 4.3 ± 3.9 years, with post-PPM LVEF being 33.7% ± 7.4% in patients with PICM vs 57.6% ± 6.1% in patients without PICM (P < .001). In multivariable analysis, lower pre-PPM LVEF (hazard ratio [HR] 1.047 per 1% LVEF decrease; 95% confidence interval [CI] 1.002-1.087; P = .042) and RV pacing % both as a continuous (HR 1.011 per 1% RV pacing; 95% CI 1.002-1.02; P = .021) and as a categorical (<20% or ≥20% RV pacing) (HR 6.76; 95% CI 2.08-22.0; P = .002) variable were independently associated with PICM. Only 29 patients with PICM (28.7%) received CRT upgrade despite an 84% responder rate (LVEF increase 18.5% ± 8.1% and left ventricular end-systolic volume decrease 45.1% ± 15.0% in responders). CRT upgrade was associated with greater post-PPM LVEF decrease, lower post-PPM LVEF, and post-PPM LVEF ≤35% (P = .006, P = .004, and P = .004, respectively). CONCLUSION PICM is not uncommon in patients receiving PPM for CHB with preserved LVEF and is strongly associated with RV pacing burden >20%. CRT response rate is high in PICM, but is perhaps underutilized.