Recurrent Ventricular Tachycardia In Patients Research Articles

Effect of Ischemia Testing and Coronary Revascularization on Mortality and Ventricular Tachycardia Recurrence in Patients With Monomorphic Ventricular Tachycardia Without Acute Coronary Syndrome: A Meta-Analysis and Systematic Review.

Studies show mixed results regarding the effect of coronary revascularization on mortality benefit and ventricular tachycardia (VT) recurrence in patients with monomorphic VT without acute coronary syndrome (ACS). This meta-analysis aimed to assess the effect of ischemia testing and/or coronary revascularization on mortality and VT recurrence in a pooled data set. Databases including PubMed, Google Scholar, and the Cochrane Library were searched from January 2000 to December 2023 for studies reporting event data on mortality and VT recurrence in patients without ACS who presented with monomorphic VT. Data were pooled and analyzed using random effects meta-analysis. The pooled sample consisted of a total of five studies, with 1062 patients, of whom 433 underwent ischemia testing and/or coronary revascularization and 629 did not. There was no statistically significant difference in the mortality and VT recurrence in the patients who underwent ischemia testing and/or revascularization versus those who did not (mortality odds ratio [OR]: 0.98; [95% confidence interval (CI): 0.62 to 1.53]; p = 0.92; VT recurrence OR: 1.07; [95% CI: 0.51 to 2.26]; p = 0.86). No publication bias was detected by examination of the funnel plot, Begg-Mazumdar's test (p = 0.80), and Egger's test (p = 0.91). In conclusion, in patients with sustained monomorphic VT in the absence of ACS, ischemia testing and/or revascularization does not lead to improved mortality or a decrease in the incidence of VT recurrence.

Role of ventricular tachycardia cycle length in the outcomes after catheter ablation or antiarrhythmic drugs in the SURVIVE-VT trial

Abstract Background It has been suggested that antiarrhythmic drugs (AAD) are less effective and safe in slow ventricular tachycardia (VT) due to their effect on conduction velocity, which could stabilize reentry. Conversely, catheter ablation aims to disrupt the VT circuit. Because of the distinct mechanisms of action of AAD and catheter ablation on the VT circuit, VT cycle length (VT-CL) may play a crucial role in determining their therapeutic efficacy. Therefore, VT-CL could be important in selecting VT treatment. Purpose The aim of this study was to assess the impact of VT-CL on outcomes following catheter ablation or antiarrhythmic drugs in AAD-naïve patients with ischemic cardiomyopathy presenting with VT. Methods This is a post hoc analysis of the previously published Substrate Ablation vs Antiarrhythmic Drug Therapy for Symptomatic Ventricular Tachycardia (SURVIVE-VT) trial. In summary, 144 patients with ischemic cardiomyopathy and symptomatic VT were randomized to receive either catheter ablation (N=71) or AAD (N=73) as first-line therapy. We analyzed VT recurrence, implantable cardioverter-defibrillator (ICD) therapies, and the incidence of slow/incessant VT/VT storm using Cox proportional hazard models, with treatment and VT-CL interaction terms, adjusted for age. Missing VT-CL data for five patients were imputed using the median value. Results In patients with chronic ischemic heart disease and VT treated with either AAD or catheter ablation, a significant interaction was observed between clinical VT-CL and treatment effect on VT recurrence (p=0.016 for the interaction). Specifically, slower VT cycle lengths were associated with higher rates of VT recurrence (hazard ratio per 10 ms [HR] 1.094, 95% confidence interval [CI] 1.015, 1.179; p=0.037) in patients treated with AAD, while no significant effect was observed in those undergoing catheter ablation (see Figure 1). Survival freedom from VT recurrence in patients with VT-CL ≥300ms was significantly higher in patients treated with catheter ablation (78.8% vs 58.1%, log-rank p=0.044, see Figure 2). As expected, VT-CL was significantly associated with a higher risk of slow/incessant VT/VT storm (HR per 10 ms 1.115, 95% CI 1.017-1.222, p=0.047) but was not associated with ICD therapies (HR per 10 ms 1.082, 95% CI 0.994-1.178, p=0.102). Conclusion VT-CL significantly influences treatment outcomes, with slower VT cycles associated with an increased risk of VT recurrence in patients treated with AAD, but not in those undergoing catheter ablation. Therefore, VT-CL should be taken into consideration when selecting the optimal therapy for patients with ischemic cardiomyopathy and VT.Figure 1Figure 2

Mineralocorticoid receptor antagonist therapy in patients with ischemic heart failure and ventricular tachycardia: a comparative analysis of spironolactone vs. eplerenone

Abstract Background Mineralocorticoid receptor antagonists (MRAs) are a cornerstone of heart failure therapy and have been shown to reduce the incidence of sudden cardiac death. However, a direct comparison between spironolactone and eplerenone in patients who present ventricular tachycardia (VT) is lacking. Purpose This study aimed to compare the effect of spironolactone and eplerenone on VT recurrence in patients with ischemic heart disease (IHD) hospitalized for VT episodes. Methods Our data utilized a registry of 405 patients with IHD and HF, who were hospitalized for an episode of sustained VT and received MRA therapy. We performed propensity score matching based on age, hypertension, diabetes, history of acute myocardial infarction, left ventricular ejection fraction (LVEF) and presentation with incessant VT. The matched population included 200 patients, stratified into two equivalent groups. Cox regression analysis was performed to identify predictors of VT recurrence, with Kaplan-Meier curves facilitating time-to-event analyses. Results The median age was 69 years and the majority (91%) were male. One-third had an ICD, and 41 patients (20%) had CRT. The median LVEF was 30%, 23 patients (12%) presented with an electrical storm, while 18 (9%) had incessant VT. VT led to hemodynamic instability in 91 cases (46%). Ablation was performed in 47 patients (24%), while 1 required mechanical circulatory support. Ablation was performed in 47 patients (24%), while 1 required mechanical circulatory support. Patients were followed for at least a year and median follow-up time was 414 days. A total of 78 patients had VT recurrence and 117 patients died. Eplerenone use significantly reduced the risk of VT recurrence compared to spironolactone (HR: 0.59 [0.37-0.93], p=0.023). This effect was consistent in the multivariate model as well (p=0.007). Conclusions Eplerenone use may confer a greater protective effect against VT recurrence in patients with IHD and sustained VT. Further studies are required to confirm these preliminary findings.

Comparison of eplerenone and spironolactone treatment in patients with ischemic heart disease hospitalized due to ventricular tachycardia

Abstract Background The beneficial effects of mineralocorticoid receptor antagonists (MRAs) regarding sudden cardiac death (SCD) risk and cardiac remodeling are well known, moreover, they also reduce episodes of ventricular tachycardia (VT). However, superiority in effectiveness between receptor selective eplerenone and conventional spironolactone is unknown. Purpose Our aim was to assess the effect of eplerenone and spironolactone on ventricular tachycardia (VT) recurrence in patients with ischemic heart disease (IHD). Methods We collected data of 563 patients with IHD following hospitalization due to a sustained VT episode in a structured registry. Propensity score matching was performed based on age, hypertension, diabetes, history of acute myocardial infarction, left ventricular ejection fraction (LVEF) and presentation with incessant VT. The matched population consisted of 188 patients and was further analyzed. Predictors were assessed using univariate and multivariate Cox regression models. Kaplan-Meier curves were used for time-to-event analyses. Results The median age was 70 years with 81% being male. One third of the patients had an ICD implanted, while 43 (23%) had CRT. The median LVEF was 30%. Twenty-five (13%) patients presented with an electrical storm and 19 (10%) had incessant VT. In 86 cases (46%), the VT caused hemodynamic instability. Ablation was performed in 66 patients (35%), while 4 required mechanical circulatory support. During the median follow-up of 856 [399-1624] days, 69 patients had VT recurrence and 118 patients died. Eplerenone use significantly reduced the risk of VT recurrence compared to spironolactone (HR: 0.48 [0.29-0.78], log-rank p=0.003). This effect was consistent in the multivariate model as well (p=0.006). Conclusions Eplerenone use may be more beneficial in terms of VT recurrence in patients with IHD who present with a sustained VT. Further analysis is required to confirm these findings.

Impact of functional gene groups on outcomes after ablation of ventricular tachycardia in patients with inherited left ventricular cardiomyopathy: an international multicentre study

Abstract Background Advances in genetic testing has enabled identification of pathogenic variants of different functional gene groups associated with non-dilated left ventricular cardiomyopathy (NDLCM)/dilated cardiomyopathy (DCM) and ventricular tachycardia (VT). However, there is limited data on the impact of functional groups on VT ablation outcome. Aim We aimed to assess the impact of likely pathogenic/pathogenic variants (LP/Pv) of different functional gene groups on heart failure (HF) outcomes and VT recurrence in patients with NDLCM/DCM after VT ablation. Methods Patients with NDLCM/DCM who underwent genetic testing (next-generation sequencing) and were referred for VT ablation were enrolled at 6 participating centers. Patients were followed for VT recurrence, HF-related adverse outcomes (death, left ventricular assist device [LVAD], or heart transplantation due to HF), and all-cause mortality. Results A total of 239 patients (age 55±14yrs; male n=193; LVEF 40±12%; amiodarone at admission n=103; ICD n=180) were included. LP/Pv were identified in 128 patients (54%), predominantly found in genes encoding sarcomeric (n=36/128, [28%]; titin n=20, myosin binding protein C n=12), followed by nuclear membrane (n=27/128, [22%]; lamin A/C; n=26), desmosomal (n=23/128, [18%]; desmoplakin n=11, plakophilin n=9), cytoskeleton (n=12/128, [9%]; filamin C n=8), and sarcoplasmic reticulum proteins (n=12/128, [9%]; phospholamban n=10). Variants of unknown significance (n=32) were grouped with patients who tested negative. Acute complete ablation success, defined as non-VT inducibility of any sustained monomorphic VT, was achieved in 113 patients (47%), 63 (56%) with LP/Pv. During a median follow-up of 32 months, 108 patients (45%) had VT recurrence, 41 (17%) had HF-related adverse outcomes (death with/without LVAD in 34, LVAD in 2, heart transplantation in 5) and 47 (20%) died. Patients with LP/Pv were more likely to have VT recurrence, HF-related adverse outcomes and had a higher mortality compared to those without (VT, 68 [53%] vs. 40 [36%]; HF-related adverse outcomes, 30 [23%] vs. 11 [10%]; mortality, 30 [23%] vs. 17 [15%]; log-rank, P<0.01 for all). As compared to patients without LP/Pv, those with LP/Pv in genes encoding nuclear membrane or sarcomeric proteins had significantly worse (P<0.01 for both) and those with LP/Pv in genes encoding desmosomal proteins had similar HF and VT recurrence outcomes (Figure). Of interest, patients with LP/Pv in genes encoding cytoskeleton proteins had favorable HF-related adverse outcomes, but worse VT recurrence (P=0.02) compared to those without LP/Pv (Figure). Conclusion In patients with NDLCM/DCM and VT, the impact of LP/Pv on HF and VT-recurrence outcomes after ablation differs across functional groups. Integrating genetic testing in the comprehensive evaluation of patients with NDLCM/DCM undergoing VT ablation may facilitate personalized ablation strategies and early consideration of alternative HF treatments.

Predictors of recurrence in patients without non-inducibility of ventricular tachycardia at the end of ablation.

Ventricular tachycardia (VT) non-inducibility at the end of ablation is associated with a less likely VT recurrence. However, it is not clear whether we should use VT non-inducibility as a routine end point of VT ablation. The aim of this study was to evaluate VT recurrence in patients in whom VT non-inducibility was not achieved at the end of the radiofrequency (RF) ablation and the factors attributing to the VT recurrence. We analyzed that 62 patients in whom VT non-inducibility was not achieved at the end of the RF ablation were studied. Over 2 years, 22 (35%) of the cases had VT recurrences. A multivariate analysis showed that an LVEF ≥35% (HR: 0.19; 95% CI: 0.06-0.49; p < .01) and elimination of the clinical VT as an acute ablation efficacy (HR: 0.23; 95% CI: 0.04-0.81; p=.02) were independent predictors of fewer VT recurrences. RF ablation was associated with a 91.1% reduction in VT episodes. Even if VT non-inducibility was not achieved, patients with an LVEF ≥35% or in whom the clinical VT could be eliminated might be prevented from having VT recurrences. The validity of the VT non-inducibility of any VT should be evaluated considering each patient's background and the results of the procedure.

Anovel ECG finding in patients with epicardial infarct-associated ventricular tachycardia: acase series.

This study analyzes the incidence, characteristics, and ECG morphology of ventricular tachycardia (VT) in post-infarction patients undergoing epicardial VT ablation. Ablation of recurrent VTs in patients with ischemic cardiomyopathy is typically performed endocardially. In rare cases, epicardial access is required to achieve non-inducibility. The study evaluated the baseline characteristics, procedural data, and ECG morphology of clinical VT in patients undergoing epicardial VT ablation. From the initial 491patients with coronary heart disease (CHD) and recurrent VTs undergoing ablation at the Heart Center of Leipzig, Germany, between 2012 and 2020, only 39patients required an additional epicardial access. In 17 patients, the VTs were associated with infarction scar, while the remaining patients had concomitant CHD without infarction-associated scar and were excluded from the analysis. Apropensity match study was performed at a1:2 ratio for these 17 patients, with 34patients of the initial cohort as a control group to evaluate the differences in baseline characteristics, procedural data, and ECG morphology of the VTs. The specific VT morphology of negative concordance and superior axis in patients with inferior scar as well as the history of VT ablation were independent predictors of the need for epicardial access. In addition to previous endocardial ablation, VT ECG morphology with negative concordance and superior axis in post-infarction patients with inferior scar predicted the need for epicardial VT ablation.

Thoracoscopic sympathectomy decreases disease burden in patients with medically refractory ventricular arrhythmias.

OBJECTIVESThoracic sympathectomy has been shown to be effective in reducing implantable cardioverter-defibrillator (ICD) shocks and ventricular tachycardia recurrence in patients with channelopathies, but the evidence supporting its use for refractory ventricular arrhythmias in patients without channelopathies is limited. This is a single-centre cohort study of bilateral R1–R4 thoracoscopic sympathectomy for medically refractory ventricular arrhythmias.METHODSClinical information was examined for all bilateral thoracoscopic R1–R4 sympathectomies for ventricular arrhythmias at our institution from 2016 through 2020.RESULTSThirteen patients underwent bilateral thoracoscopic R1–R4 sympathectomy. All patients had prior ICD implant. Patients had a recent history of multiple ICD discharges (12/13), catheter ablation (10/13) and cardiac arrest (3/13). Ten patients were urgently operated on following transfer to our centre for sustained ventricular tachycardia. Seven patients had ventricular tachycardia ablations preoperatively during the same admission. Five patients were in intensive care immediately preoperatively, with 3 requiring mechanical ventilation. Three patients suffered in-hospital mortality. Kaplan–Meier analysis estimated 73% overall survival at 24-month follow-up. Among the 10 patients who survived to discharge, all were alive at a median follow-up of 8.7 months (interquartile range 0.6–26.7 months). Six of 10 patients had no further ICD discharges. Kaplan–Meier analysis estimated 27% ICD shock-free survival at 24 months follow-up for all patients. Three of 10 patients had additional ablations, while 2 patients underwent cardiac transplantation.CONCLUSIONSBilateral thoracoscopic sympathectomy is an effective option for patients with life-threatening ventricular arrhythmia refractory to pharmacotherapy and catheter ablation.

VT recurrence and predictors in patients with VT inducibility at the end of VT ablation

Abstract Background A successful Radiofrequency (RF) ablation of ventricular tachycardia (VT) can prevent VT recurrence. It has been reported that VT non-inducibility at the end of RF ablation is associated with less likely VT recurrence in ischemic cardiomyopathy (ICM) and non-ICM (NCIM). However, it is not clear whether we should use VT non-inducibility as routine end point in RF ablation of VT. Purpose The aim of this study was to evaluate VT recurrence in patients who couldn't be achieved VT non-inducibility at the end of RF ablation and the factors attributed to VT recurrence in ICM and NICM patients. Methods Between January 2009 and April 2020, 84 consecutive patients (ICM: 34, NICM: 50) underwent RF ablation for drug-resistant VT in our hospital. VT non-inducibility was defined as any ventricular tachy-arrhythmia, including clinical VT, non-clinical VT, and VF, was not induced by programed stimuli at the end of session. Non-inducibility was achieved in 37 patients but it was not achieved in 47 patients (ICM: 18, NICM: 29). To evaluate the validity of “non-inducibility” as an end point of VT ablation, 47 patients (male: 40, mean age: 66±15 years) in whom non-inducibility of any ventricular tachyarrhythmia was not achieved were studied. The primary endpoint was recurrence of any sustained VT and VF during follow up period (mean follow-up period was 1.4 (range, 0.0, 2.0) years.) Results Mean left ventricular ejection fraction (LVEF) was 36±13%. Epicardial ablation was required in 8 patients. 32 patients had electrical storm at the time of ablation. Among them, 21 patients had VT recurrence and 26 patients had non-VT recurrence during follow-up period. VT recurrence rate was significantly lower in patients with LVEF≥35% than those with LVEF&amp;lt;35% (HR=0.31, 95% CI 1.25–9.92). Multivariate survival analysis identified LVEF≥35% (HR=0.34, 95% CI 0.10–0.98) and ablation of VT isthmus (HR=0.18, 95% CI 0.02–0.78) as independent predictors of non-VT recurrence. Conclusions Even if non-inducibility of any ventricular tachyarrhythmia wasn't achieved at the end of ablation, the patients with LVEF≥35% or who had ablated of VT isthmus might prevent VT recurrence. The validity of non-inducibility of any ventricular tachyarrhythmia should be evaluated in each patient's background. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Abbott, Medtronic

Electrophysiological predictors of ventricular tachycardia recurrence in patients with structural heart disease after combined endo-epicardial substrate catheter ablation

Abstract Background Although there is a tremendous improvement in mapping and ablation techniques over the last decades, the recurrence rate of ventricular tachycardia (VT) in patients with structural heart diseases following endo-epicardial catheter ablation remains high. Purpose To determine predictors of VT recurrence in patients with structural heart disease after combined endo-epicardial radiofrequency (RF) VT ablation. Methods This prospective single-center study included 39 patients (34 men and 5 women, mean age 49.6±16.0 years), who underwent endo-epicardial mapping and ablation of the VT substrate. Etiology of structural heart diseases included: previous myocardial infarction (n=15); non-ischemic cardiomyopathy (n=24: 15 – arrhythmogenic right ventricular cardiomyopathy (ARVC), 6 – myocarditis, 3 – unspecified). First-line epicardial access was performed in 16 patients, as a second approach – in 23 subjects. We evaluated total ventricular myocardial areas, epi- and endocardial areas with bipolar low voltage (&amp;lt;1.5mV), scar area (bipolar &amp;lt;0.5mV), and unipolar low voltage (&amp;lt;5.0mV) and transient (&amp;lt;8.0mV) areas; areas of late potential registration were evaluated. Ratios of transient, low amplite and late-potential areas were calculated for endo- and epicardial surfaces, bipolar and unipolar maps. The following procedural electrophysiology characteristics were considered: inducibility of clinical VT, the number and morphology of induced VT, QRS width on sinus rhythm and VT, tachycardia cycle length, pseudo-delta wave extant and width, internal activation time, intrisicoud deflection time, and RS length. Clinical data such as echocardiography parameters, comorbidity and antiarrhythmic drug therapy were also taken into account. VT recurrences were documented using ICD/CRT-D interrogation, event ECG monitoring. Follow-up included mandatory visits at 6 and 12 months and unscheduled visits. Results Epicardial late potentials were registered in 69% of cases before ablation. Epicardial RF applications were delivered in 67% of patients; while only endocardial RF applications (including cases with intended epicardial substrate modification by endocardial ablation) were present in 28% cases. Non-inducibility of any VT plus abatement of local abnormal electrical activity was achieved in 32 (82%) of cases. The ratio epi/endo bipolar areas &amp;lt;0.5mV was much higher in patients with vs without VT recurrence at 6 months (4.3 (IQR: 2.5; 8.2) vs 0.75 (IQR:0.4; 1.6), P=0.001). A strong negative correlation was found between the induced VT cycle length and the ratio epi/endo bipolar areas &amp;lt;0.5mV: the shorter induced VT cycle length -the larger the area of the epicardial low voltage area (r=−0,52). Conclusion Regardless of epicardial substrate modification, patients with a larger epicardial low voltage area are more likely to have VT recurrence at 6 months after index ablation. A shorter induced VT cycle length is associated with a larger epicardial low-voltage area. Funding Acknowledgement Type of funding sources: None.

Factors associated with recurrent postinfarction ventricular tachycardia following ablation.

INTRODUCTION Ablation of ventricular tachycardia is the main therapy for patients with drug-refractory ventricular tachycardia (VT). Although evidence suggests that VT ablation could lower the incidence of recurrent VT, many cases still develop VT in follow-up. In this study, we performed a systematic review and meta-analysis to examine risk factors for recurrent VT in patients with postinfarction VT who underwent VT ablation. EVIDENCE ACQUISITION We comprehensively searched the databases of MEDLINE and EMBASE from inception to March 2020. Included studies were cohort studies, experimental trials, or randomized controlled trials that evaluate the risk of recurrent VT in postinfarction VT patients who underwent VT ablation. Data from each study were combined using random-effects. EVIDENCE SYNTHESIS Thirteen studies involving 1803 postinfarction patients who underwent VT ablation were included. Inducibility after the procedure (pooled HR=1.71, P<0.001), lower baseline left ventricular ejection fraction (LVEF) (pooled HR=0.98, P<0.001) and higher baseline New York Heart Association (NYHA) classification (pooled HR=1.34, P=0.003) were significantly associated with VT recurrence during the follow-up. There was no significant association between age, gender or diabetes mellitus and VT recurrence. CONCLUSIONS Our meta-analysis demonstrated that inducibility after the procedure, lower baseline LVEF and higher baseline NYHA classification were associated with an increased risk of VT recurrence in postinfarction VT patients who underwent VT ablation.

Arrhythmic Risk Profile and Outcomes of Patients Undergoing Cardiac Sympathetic Denervation for Recurrent Monomorphic Ventricular Tachycardia After Ablation.

BackgroundCardiac sympathetic denervation (CSD) has been used as a bailout strategy for refractory ventricular tachycardia (VT). Risk of VT recurrence in patients with scar‐related monomorphic VT referred for CSD and the extent to which CSD can modify this risk is unknown. We aimed to quantify arrhythmia recurrence risk and impact of CSD in this population.Methods and ResultsAdjusted competing risk time to event models were developed to adjust for risk of VT recurrence and sustained VT/implantable cardioverter–defibrillator shocks after VT ablation based on patient comorbidities at the time of VT ablation. Adjusted VT and implantable cardioverter–defibrillator shock recurrence rates were estimated for the subgroup who subsequently required CSD after ablation. The expected adjusted recurrence rates were then compared with the observed rates after CSD. Data from 381 patients with scar‐mediated monomorphic VT who underwent VT ablation were analyzed, excluding patients with polymorphic VT. Sixty eight patients underwent CSD for recurrent VT. CSD reduced the expected adjusted VT recurrence rate by 36% (expected rate of 5.61 versus observed rate of 3.58 per 100 person‐months, P=0.01) and the sustained VT/implantable cardioverter–defibrillator shock rates by 34% (expected rate of 4.34 versus observed 2.85 per 100 person‐months, P=0.03). The median number of sustained VT/implantable cardioverter–defibrillator shocks in the year before versus the year after CSD was reduced by 90% (10 versus 1, P<0.0001).ConclusionsPatients referred for CSD for refractory scar‐mediated monomorphic VT are at a higher risk of VT recurrence after ablation as compared with those not requiring CSD, mostly because of their cardiac comorbidities. CSD significantly reduced both the expected risk of recurrences and VT burden.

Factors associated with recurrent postinfarction ventricular tachycardia following ablation.

Ablation of ventricular tachycardia is the main therapy for patients with drug-refractory ventricular tachycardia (VT). Although evidence suggests that VT ablation could lower the incidence of recurrent VT, many cases still develop VT in follow-up. In this study, we performed a systematic review and meta-analysis to examine risk factors for recurrent VT in patients with postinfarction VT who underwent VT ablation. We comprehensively searched the databases of MEDLINE and EMBASE from inception to March 2020. Included studies were cohort studies, experimental trials, or randomized controlled trials that evaluate the risk of recurrent VT in postinfarction VT patients who underwent VT ablation. Data from each study were combined using random-effects. Thirteen studies involving 1803 postinfarction patients who underwent VT ablation were included. Inducibility after the procedure (pooled HR=1.71, P<0.001), lower baseline left ventricular ejection fraction (LVEF) (pooled HR=0.98, P<0.001) and higher baseline New York Heart Association (NYHA) classification (pooled HR=1.34, P=0.003) were significantly associated with VT recurrence during the follow-up. There was no significant association between age, gender or diabetes mellitus and VT recurrence. Our meta-analysis demonstrated that inducibility after the procedure, lower baseline LVEF and higher baseline NYHA classification were associated with an increased risk of VT recurrence in postinfarction VT patients who underwent VT ablation.

Long-Term Outcome After Ventricular Tachycardia Ablation in Nonischemic Cardiomyopathy: Late Potential Abolition and VT Noninducibility.

In patients with an ischemic cardiomyopathy (ICM), the combination of late potential (LP) abolition and postprocedural ventricular tachycardia (VT) noninducibility is known to be the desirable end point for a successful long-term outcome after VT ablation. We investigated whether LP abolition and VT noninducibilty have a similar impact on the outcomes of patients with non-ICMs (NICM) undergoing VT ablation. A total of 403 patients with NICM (523 procedures) who underwent a VT ablation from 2010 to 2016 were included. The procedure end points were the LP abolition (if the LPs were absent, other ablation strategies were undertaken) and the VT noninducibilty. The underlying structural heart disease consisted of dilated cardiomyopathy (DCM, 49%), arrhythmogenic right ventricular dysplasia (ARVD, 17%), postmyocarditis (14%), valvular heart disease (8%), congenital heart disease (2%), hypertrophic cardiomyopathy (2%), and others (5%). The epicardial access was performed in 57% of the patients. At baseline, the LPs were present in 60% of the patients and a VT was either inducible or sustained/incessant in 85% of the cases. At the end of the procedure, the LP abolition was achieved in 79% of the cases and VT noninducibility in 80%. After a multivariable analysis, the combination of LP abolition and VT noninducibilty was independently associated with free survival from VT (hazard ratio, 0.45 [95% CI, 0.29-0.69], P=0.0002) and cardiac death (hazard ratio, 0.38 [95% CI, 0.18-0.74], P=0.005). The benefit of the LP abolition on preventing the VT recurrence in patients with ARVD and postmyocarditis appeared superior to that observed for those with DCM. In patients with NICM undergoing VT ablation, the strategy of LP abolition and VT noninducibilty were associated with better outcomes in terms of long-term VT recurrences and cardiac survival. Graphic Abstract: A graphic abstract is available for this article.

Prevention of Recurrent Ventricular Tachycardia in Patients With Implantable Cardioverter Defibrillators-A Network Meta-analysis.

The optimal management for the prevention of recurrent ventricular tachycardia in patients with implantable cardioverter-defibrillators (ICDs) offers a challenge with no set guidelines regarding which therapy offers a best safety and efficacy profile. Which therapeutic strategy, among antiarrhythmic drugs and catheter ablation (CA), offers the most effective and safe approach in patients with ICDs? Randomized controlled trials (RCTs) comparing the efficacy and safety of antiarrhythmic drugs or CA against a placebo group. RCTs were identified from a comprehensive search in PubMed, Embase, and Cochrane library. Our outcomes of interest were reductions in appropriate ICD shocks, inappropriate ICD shocks, and overall mortality. We used the event rates in both groups, and then using a frequentist approach employing a graph theory methodology, we constructed a network meta-analysis model. Fourteen RCTs with 3815 participants and 6 different interventions treatments were included in our network meta-analysis. The most effective treatment for the prevention of recurrent ventricular tachycardia after ICD is amiodarone followed by CA. Amiodarone is most effective in the reduction of appropriate and inappropriate ICD shocks with an odds ratio (OR) of 0.29 [95% confidence interval (CI), 0.11-0.74] and 0.15 (95% CI, 0.04-0.60), respectively. CA was effective in the reduction of appropriate ICD shocks (OR, 0.41; 95% CI, 0.20-0.87), whereas sotalol was effective in the reduction of inappropriate ICD shocks (OR, 0.46; 95% CI, 0.22-0.95). There was no significant reduction in the overall mortality from any therapy. There was a trend of increased mortality associated with amiodarone therapy (OR, 2.40; 95% CI, 0.92-6.26). Amiodarone remains the most efficacious therapy for the reduction of appropriate and inappropriate shocks in patients with ICD. No therapy resulted in mortality reduction, but amiodarone showed a trend toward increased mortality.

Outcomes of Catheter Ablation in Arrhythmogenic Right Ventricular Cardiomyopathy Without Background Implantable Cardioverter Defibrillator Therapy: A Multicenter International Ventricular Tachycardia Registry.

This study sought to determine the long-term outcomes of catheter ablation (CA) of ventricular tachycardia (VT) in a series of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) without background implantable cardioverter-defibrillator (ICD) therapy. Endo-epicardial CA of VT has been demonstrated to be highly effective in reducing recurrent VT in patients with ARVC. Thirty-two patients (age 45 ± 13 years, 72% male) with ARVC and VT underwent CA in the absence of ICD therapy. ICD was recommended in all cases, but implantation was not performed due to patient refusal (63%) or financial hardship (37%). CA was guided by activation/entrainment mapping for mappable VT and pace mapping/targeting of abnormal substrate in cases of unmappable VT. Symptoms associated with clinical VT included palpitations (78%), chest pain and shortness of breath (22%), pre-syncope (16%), and syncope (13%). Prior to ablation, 22 patients (69%) failed a mean of 1.3 ± 0.5 antiarrhythmic drugs. Epicardial mapping and ablation was performed as first-line strategy (20 [63%]) or in case of recurrent VT or persistent inducibility after endocardial-only ablation (3 [9%]-surgical epicardial cryoablation in 1 patient). After a mean of 1.6 (range 1 to 3) procedures, all patients demonstrated noninducibility of sustained VT from at least 2 RV sites; 75% also had stimulation on isoproterenol with no inducible VT. At a median follow-up of 46 months (range 26 to 65 months) following the last ablation, no deaths were observed and freedom from recurrent VT was 81%. In this multicenter international registry of patients with ARVC and VT, CA performed in the absence of background ICD was associated with a low rate of symptomatic VT recurrence (19%) without mortality during 46-month median follow-up. These data suggest that further prospective studies may refine selection of patients with structural heart disease at low risk for SCD, possibly obviating the benefit of ICD therapy.

Comparative effectiveness of antiarrhythmic drugs and catheter ablation for the prevention of recurrent ventricular tachycardia in patients with implantable cardioverter-defibrillators: A systematic review and meta-analysis of randomized controlled trials

Treatment strategies to prevent ventricular tachycardia (VT) in patients with an implantable cardioverter-defibrillator (ICD) include antiarrhythmic drugs (AADs) and catheter ablation (CA). The purpose of this study was to systematically compare the efficacy of AADs and CA for the prevention of VT in patients with ICDs. Major databases were searched (October 2015) for randomized trials evaluating AADs or CA vs standard medical therapy to prevent VT in ICD patients. Primary outcome was the number of VT episodes leading to appropriate ICD interventions. Eight trials (n = 2268, follow-up 15 ± 6 months) evaluated AADs, and 6 trials (n = 427, follow-up 14 ± 8 months) evaluated CA. A significant reduction in appropriate ICD interventions was found with both CA (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.28-0.71, P = .001) and AADs (OR 0.66, 95% CI 0.44-0.97, P = .037), with no significant difference between the 2 treatment strategies. The benefit of AADs was driven by amiodarone and not confirmed with other AADs. A reduction of inappropriate ICD interventions was found with AADs (OR 0.30, P = .001) but not with CA. Both CA and AADs were not associated with decreased mortality over follow-up. Amiodarone appeared to increase the risk of death (OR 3.36, 95% CI 1.36-8.30, P = .009). In patients with an ICD, both AADs (amiodarone) and CA reduce the risk of recurrent VT compared to control medical therapy, with no significant difference between the 2 treatments. AADs are also associated with a reduction of inappropriate ICD therapies. The significant reduction of recurrent VT episodes does not appear to result in a mortality benefit, with a potential for increased mortality with amiodarone.

Ablation of Stable VTs Versus Substrate Ablation in Ischemic Cardiomyopathy: The VISTA Randomized Multicenter Trial

BackgroundCatheter ablation reduces ventricular tachycardia (VT) recurrence and implantable cardioverter defibrillator shocks in patients with VT and ischemic cardiomyopathy. The most effective catheter ablation technique is unknown. ObjectivesThis study determined rates of VT recurrence in patients undergoing ablation limited to clinical VT along with mappable VTs (“clinical ablation”) versus substrate-based ablation. MethodsSubjects with ischemic cardiomyopathy and hemodynamically tolerated VT were randomized to clinical ablation (n = 60) versus substrate-based ablation that targeted all “abnormal” electrograms in the scar (n = 58). Primary endpoint was recurrence of VT. Secondary endpoints included periprocedural complications, 12-month mortality, and rehospitalizations. ResultsAt 12-month follow-up, 9 (15.5%) and 29 (48.3%) patients had VT recurrence in substrate-based and clinical VT ablation groups, respectively (log-rank p < 0.001). More patients undergoing clinical VT ablation (58%) were on antiarrhythmic drugs after ablation versus substrate-based ablation (12%; p < 0.001). Seven (12%) patients with substrate ablation and 19 (32%) with clinical ablation required rehospitalization (p = 0.014). Overall 12-month mortality was 11.9%; 8.6% in substrate ablation and 15.0% in clinical ablation groups, respectively (log-rank p = 0.21). Combined incidence of rehospitalization and mortality was significantly lower with substrate ablation (p = 0.003). Periprocedural complications were similar in both groups (p = 0.61). ConclusionsAn extensive substrate-based ablation approach is superior to ablation targeting only clinical and stable VTs in patients with ischemic cardiomyopathy presenting with tolerated VT. (Ablation of Clinical Ventricular Tachycardia Versus Addition of Substrate Ablation on the Long Term Success Rate of VT Ablation (VISTA); NCT01045668)

Procedural Outcomes and Survival After Catheter Ablation of Ventricular Tachycardia in Relation to Electroanatomical Substrate in Patients With Nonischemic-Dilated Cardiomyopathy: The Role of Unipolar Voltage Mapping.

In patients with ischemic cardiomyopathy the size of bipolar low-voltage areas (LVA) in electroanatomical maps (EAM) was associated with poorer outcomes after catheter ablation (CA) of ventricular tachycardia (VT). However, the effect of LVA size on the survival after VT ablation in patients with nonischemic dilated cardiomyopathy (NIDCM) has not been studied. In 55 patients with NIDCM (48 male, age 61 ± 16 years, ejection fraction 32 ± 13%) an EAM to delineate the bipolar and unipolar LVAs was performed in 52 (94.5%) patients endocardially, in 24 (43.6%) patients epicardially, and in 21 (38.2%) patients on both surfaces. Additionally, activation mapping of the VT was possible in 22 (40%) patients. CA with lines transecting the scar and targeting late potentials was performed in all patients. Complete VT noninducibility at the end was achieved in 40 (72.7%) patients. During the median follow-up of 22 (interquartile range IQR 6, 34) months, VT recurrences were observed in 30 (54.5%) and cardiac death in 14 (25.5%) patients. The ROC analysis revealed that the size of endocardial unipolar LVA (<8.3 mV) was associated with cardiac death (AUC 0.89, 95% CI 0.79-0.98, P <0.0001). UVA = 145 cm2 discriminates for cardiac death with 83% sensitivity and 78% specificity. Endocardial UVA > 145 cm2 was a predictor for cardiac death (adjusted HR = 6.9; P = 0.014) and UVA ≥ 54% (of total endocardial LV surface) for VT recurrence (adjusted HR = 3.5; P = 0.016). The size of endocardial unipolar LVA (<8.3 mV) was a strong and independent predictor for cardiac mortality and VT recurrence in patients with NIDCM.

Meta-analysis of catheter ablation as an adjunct to medical therapy for treatment of ventricular tachycardia in patients with structural heart disease

Most studies of catheter ablation for the treatment of ventricular tachycardia (VT) are relatively small observational trials. The purpose of this study was to define the relative risk of VT recurrence in patients undergoing catheter ablation as an adjunct to medical therapy versus medical therapy alone in a pooled analysis of controlled studies. Randomized and nonrandomized controlled trials of patients who underwent adjunctive catheter ablation of VT versus medical therapy alone were sought. MEDLINE, EMBASE, the Cochrane central register of controlled trials (CENTRAL), and Web of Science were searched from 1965 to July 2010. Supplemental searches included Internet resources, reference lists, and reports of arrhythmia experts. Three authors independently reviewed and extracted the data regarding baseline characteristics, ablation methodology, medical therapy, complications, VT recurrences, mortality, and study quality. Five studies were included totaling 457 participants with structural heart disease. Adjunctive catheter ablation was performed in 58% of participants, whereas 42% received medical therapy alone for VT. Complications of catheter ablation included death (1%), stroke (1%), cardiac perforation (1%), and complete heart block (1.6%). Using a random-effects model, a statistically significant 35% reduction in the number of patients with VT recurrence was noted with adjunctive catheter ablation (P<.001). There was no statistically significant difference in mortality. Catheter ablation as an adjunct to medical therapy reduces VT recurrences in patients with structural heart disease and has no impact on mortality.