Juan Carlos Diaz

Long-term outcomes of different ablation strategies for ventricular tachycardia in patients with structural heart disease: Systematic review and meta-analysis

AimsnTo compare the long-term outcomes of standard ablation of stable ventricular tachycardia (VT) vs. substrate modification, and of complete vs. incomplete substrate modification in patients with structural heart disease (SHD) presenting with VT.nnnMethods and resultsnAn electronic search was performed using major databases. The main outcomes were a composite of long-term ventricular arrhythmia (VA) recurrence and all-cause mortality of standard ablation of stable VT vs. substrate modification, and long-term VA recurrence in complete vs. incomplete substrate modification. Six studies were included for the comparison of standard ablation of stable VT vs. substrate modification, with a total of 396 patients (mean age 63 ± 10 years, 87% males), and seven studies were included to assess the impact of extensive substrate modification, with a total of 391 patients (mean age 64 ± years, 90% males). More than 70% of all the patients included had ischaemic cardiomyopathy. Substrate modification was associated with decreased composite VA recurrence/all-cause mortality compared to standard ablation of stable VTs [risk ratio (RR) 0.57, 95% confidence interval (CI) 0.40-0.81]. Complete substrate modification was associated with decreased VA recurrence as compared to incomplete substrate modification (RR 0.39, 95% CI 0.27-0.58).nnnConclusionnIn patients with SHD who had VT related mainly to ischaemic substrates, there was a significantly lower risk of the composite primary outcome of long-term VA recurrence and all-cause mortality among those undergoing substrate modification compared to standard ablation. Long-term success is improved when performing complete substrate modification.

Benefit of left atrial appendage electrical isolation for persistent and long-standing persistent atrial fibrillation: a systematic review and meta-analysis

AimsnThe long-term outcomes of left atrial appendage electrical isolation (LAAEI) in patients with non-paroxysmal atrial fibrillation (AF) have corroborated the significant role of the LAA in this arrhythmia. We sought to investigate the incremental benefit of LAAEI in patients undergoing catheter ablation for persistent AF or long-standing persistent AF (LSPAF).nnnMethods and resultsnA systematic review of Medline, Cochrane, and Embase for all the clinical studies in which assessment LAAEI in non-paroxysmal AF patients was performed. The benefit of LAAEI in patients with AF was analysed from seven studies that enrolled a total of 930 patients [mean age 63u2009±u20095u2009years; male: 69%]. All studies included patients with either persistent AF or LSPAF or the combination of them. The overall freedom from all-arrhythmia recurrence at 12 months of follow-up off antiarrhythmic medications in patients who underwent LAAEI was 75.5% vs. 43.9% in those in whom only standard ablation was performed [56% relative reduction and 31.6% absolute reduction; risk ratio (RR) 0.44, 95% confidence interval (95% CI) 0.31-0.64; Pu2009<u20090.0001]. The rate of ischaemic stroke in the LAAEI group was 0.4% and in the control group 2.1% at 12u2009months follow-up (RR 0.40, 95% CI 0.12-1.30; Pu2009=u20090.13). Acute complications rates were identical between groups [LAAEI 5.5%, control 5.5% (RR 0.99, 95% CI 0.46-2.16; Pu2009=u20090.99)].nnnConclusionnLeft atrial appendage electrical isolation in addition to standard ablation appears to have a substantial incremental benefit to achieve freedom from ALL atrial arrhythmias in patients with persistent AF and LSPAF without increasing acute procedural complications and without raising the risk of ischaemic stroke.

Atrial fibrillation inducibility during cavo-tricuspid isthmus dependent atrial flutter ablation for the prediction of clinical atrial fibrillation

BACKGROUNDnAtrial fibrillation (AF) and cavo-tricuspid isthmus (CTI) dependent atrial flutter (AFL) are two separate entities that coexist in a significant percentage of patients.nnnMETHODSnWe sought to investigate whether AF inducibility during CTI AFL ablation predicted the occurrence of AF at follow up after AFL ablation. Univariate and multivariate analyses were performed.nnnRESULTSnA total of 154 patients (male: 72%, age: 61±13) with AFL and without history of AF were included. All patients underwent successful CTI dependent AFL ablation demonstrated by bidirectional block. During ablation, AF was seen or induced in 28 (18%) patients. After a mean follow up of 34±24months a total of 50 patients (32%) were noted with clinically manifest AF. From the patients who had inducible AF during AFL ablation, 50% developed post-procedural AF. From those in whom AF could not be induced, only 29% were documented with AF after ablation. Univariate and multivariate analyses revealed that only age and AF inducibility during AFL ablation were predictors of AF. Univariate analysis (age p=0.038 and inducible AF p=0.032 with odds ratio of 1.030 [95% CI (1.002-1.059)] and 2.500 [95% CI (1.084-5.765)], respectively) and multivariate analyses (age p=0.011 and inducible AF p=0.016 with adjusted odds ratio of 1.043 [95% CI (1.010-1.077)] and 3.293 [95% CI (1.250-8.676)], respectively).nnnCONCLUSIONnAF inducibility in patients undergoing CTI AFL without history of AF is a strong predictor of AF occurrence in the future. Appropriate cardiology follow-up must be encouraged in this high-risk population as stroke prevention strategies can be appropriately introduced in a timely matter especially in patients with elevated CHA2DS2-VASc scores (≥2).

Early Versus Late Referral for Catheter Ablation of Ventricular Tachycardia in Patients With Structural Heart Disease: A Systematic Review and Meta-Analysis of Clinical Outcomes

OBJECTIVESnThis was a meta-analysis of published studies to examine the impact of early referral on outcomes after catheter ablation for ventricular tachycardia (VT) in patients with structural heart disease.nnnBACKGROUNDnPatients are frequently referred for VT ablation after failure of antiarrhythmic drugs to control VT. Some studies have suggested that early referral might confer better outcomes.nnnMETHODSnAn electronic search was performed using major databases. The primary outcomes were long-term VT recurrence and total mortality. Secondary outcomes were acute procedural success and acute complications.nnnRESULTSnThree studies were included with a total of 980 patients (mean age 64 ± 12 years, 71% males). Mean follow-up was 29 ± 27 months. Early referral for VT ablation was associated with decreased VT recurrence and acute complications compared with late referral (relative risk: 0.69 [95% confidence interval: 0.58 to 0.82], pxa0< 0.0001 and relative risk: 0.50 [95% confidence interval: 0.27 to 0.93], pxa0= 0.03, respectively). There was no significant difference between early and late referral for total mortality and acute success.nnnCONCLUSIONSnLate referral for VT ablation was associated with worse outcomes (VT recurrence and acute complications)xa0in patients with structural heart disease, which suggests that early referral for VT ablation might be a reasonable consideration in this patient population.

Atrial fibrillation inducibility during cavotricuspid isthmus-dependent atrial flutter ablation as a predictor of clinical atrial fibrillation. A meta-analysis

BackgroundAtrial fibrillation (AF) and cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) are two separate entities that coexist in a significant percentage of patients. We sought to investigate whether AF inducibility during CTI AFL ablation predicted the occurrence of AF at follow-up after successful AFL ablation.MethodsA systemic review of Medline, Cochrane, and Embase was done for all the clinical studies in which assessment of AF inducibility in patients undergoing ablation for CTI AFL was performed. Given the low heterogeneity (i.e., I2 <25), we used a fixed effect model for our analysis.ResultsA total of 10 studies (4 prospective and 6 retrospective) with a total of 1299 patients (male, 73%; mean age 59u2009±u200911xa0years) fulfilled the inclusion criteria. During a mean follow-up period of 23u2009±u20097.6xa0months, 407 patients (31%) developed AF during AFL ablation. The overall incidence for new-onset AF during follow-up was 29% (47% in the group with inducible AF vs. 21% in the non-inducible group). The odds ratio (OR) for developing AF after AFL ablation in patients with AF inducibility for all studies combined was 3.72, 95% CI 2.83–4.89 [prospective studies (OR 5.52, 95% CI 3.23–9.41) vs. retrospective studies (OR 3.23, 95% CI 2.35–4.45)].ConclusionsAlthough ablation for CTI AFL is highly effective, AF continues to be a long-term risk for individuals undergoing this procedure. AF induced by pacing protocols in patients undergoing CTI AFL predicts for future AF. Inducible AF is a clinically relevant finding that may help guide decisions for long-term anticoagulation after successful typical AFL ablation especially in patients with elevated CHADS-VASc scores (≥2) and in considering prophylactic PVI during CTI AFL ablation.

Clinical outcomes in patients with atrial fibrillation receiving amiodarone on NOACs vs. warfarin

PurposeAmiodarone is a potent inhibitor of the CYP450:3A4 and inhibitor of the P-glycoprotein, both of which metabolize new oral anticoagulants (NOACs). Patients who are on NOACs and are concomitantly treated with amiodarone may have a higher risk of major bleeding according to recent retrospective trials. Whether this increased risk outweighs the benefits of NOACs compared to warfarin is unknown. We aimed to compare clinical outcomes between NOACs and warfarin in patients with atrial fibrillation (AF) being treated with amiodarone.MethodsWe performed a systematic review of MEDLINE, Cochrane, and Embase for randomized controlled trials that compared NOACs to warfarin for prophylaxis of ischemic stroke/thromboembolic events (TEs) in patients with AF and reported outcomes on TE, major bleeding, and intracranial bleeding (ICB). Risk ratio (RR) and 95% confidence intervals were measured using the Mantel-Haenszel method. Fixed effects model was used, and if heterogeneity (I2) was >u200925%, effects were analyzed using a random model.ResultsA total of four studies comparing NOACs to warfarin were included in the analysis. The total number of patients on amiodarone was 6197. Mean follow up was 23u2009±u20095xa0months. No statistically significant difference for TE prevention (RR, 0.73; 95% CI 0.50–1.07), major bleeding (RR, 1.02; 95% CI 0.68–1.53), or ICB outcomes (RR, 0.58; 95% CI 0.22–1.51) between patients on NOACs + amiodarone when compared to patients on warfarin + amiodarone.ConclusionAmong patients with AF taking amiodarone, there is no increased risk of stroke, major bleeding, or ICB with NOACs compared to warfarin.

Assessment of Implantable Cardioverter-Defibrillator Used in Heart Failure with Reduced Ejection Fraction as Primary Prevention in an Underserved Population

Implantable cardioverter-defibrillator (ICD) implantation has been one of the milestones in the treatment of heart failure providing a significant survival benefit. Current guidelines recommend that patients who have a sustained low left ventricular ejection fraction (LVEF) of 35% or less should be evaluated for ICD for primary prophylaxis (P-ICD). Our study aimed to investigate the use of P-ICD and associated outcomes in Jacobi Medical Center, a municipal New York City public teaching hospital serving an inner-city patient population located in Bronx, NY.

Combined Endocardial-Epicardial Versus Endocardial Catheter Ablation Alone for Ventricular Tachycardia in Structural Heart Disease: A Systematic Review and Meta-Analysis

OBJECTIVESnThis study sought to determine whether combined endocardial-epicardial (endo-epi) ablation was superior to endocardial only ablation in patients with scar-related ventricular tachycardia (VT).nnnBACKGROUNDnLimited single-center studies suggest that combined endo-epi ablation strategy may be superior to endocardial ablation (endo) alone in patients with nonischemic cardiomyopathy (NICM) and arrhythmogenic right ventricular cardiomyopathy (ARVC), and ischemic cardiomyopathy (ICM).nnnMETHODSnA systematic review of Medline, Cochrane, and Embase databases was performed for studies that reported outcomes comparing endo-epi with endo VT ablation alone.nnnRESULTSnSeventeen studies consisting of 975 patients were included (mean 56 ± 10 years of age; 79% male; NICM in 36.6%; ICM in 32.8%; and ARVC in 30.6%). After a mean follow-up of 27 ± 21 months, endo-epi ablation was associated with a 35% reduction in risk of VT recurrence compared with endocardial ablation alone (risk ratio [RR]: 0.65; 95% confidence interval [CI]: 0.55 to 0.78; pxa0< 0.001). Sensitivity analysis showed lower risk of VT recurrence in ICM (RR: 0.43; 95% CI: 0.28 to 0.67; pxa0= 0.0002) and ARVC (RR: 0.59; 95% CI: 0.43 to 0.82; pxa0= 0.0002), with a nonsignificant trend in NICM (RR: 0.87; 95% CI: 0.70 to 1.08; pxa0= 0.20). Endo-epi, compared with endo ablation, was associated with reduced all-cause mortality (RR: 0.56; 95% CI: 0.32 to 0.97; pxa0= 0.04). Acute procedural complications were higher with the endo-epi approach (RR: 2.62; 95% CI: 0.91 to 7.52; pxa0= 0.07).nnnCONCLUSIONSnThis meta-analysis suggests that a combined endo-epi ablation is associated with a lower risk of VTxa0recurrence and subsequent mortality than endo only VT ablation in patients with scar-related VT. Procedural complications, however, are higher with the endo-epi approach.

Intramyocardial radiofrequency ablation of ventricular arrhythmias using intracoronary wire mapping and a coronary reentry system: Description of a novel technique

Key Teaching Points n n• Ventricular arrhythmias originating from the left ventricular summit and intramyocardially within the interventricular septum pose a serious challenge to catheter ablation, as myocardial thickness, epicardial fat, and coronary vessels impede appropriate radiofrequency energy delivery. n• Intracoronary mapping and subsequent intramyocardial ablation using radiofrequency ablation delivered through a system routinely used to treat coronary artery chronic total occlusions (ie, Stingray LP Coronary CTO Re-Entry System) is feasible and effective. n• Unlike alcohol injection and coil embolization of septal perforator arteries, intramyocardial RF ablation using this technique is a more localized and limited approach with less risk of complete atrioventricular block and less myocardial injury.

Lyme disease and cardiac sarcoidosis: Management of associated ventricular arrhythmias

Cardiovascular involvement in Lyme disease is a rarely occurring manifestation. Following infection with Borrelia burgdorferi, Lyme carditis typically presents as atrioventricular (AV) block during the early disseminated stage of the disease ranging from PR interval prolongation to complete heart block, typically resolving after proper antibiotic treatment. Interestingly, AV block is also common in patients with cardiac sarcoidosis (CS), and CS has been linked to Lyme disease. We report a patient who was diagnosed with Lyme carditis and ultimately developed CS.