Ventricular Tachycardia Ablation In Patients Research Articles

Role of Cardiac Magnetic Resonance Imaging in the Management and Treatment of Ventricular Tachycardia in Patients With Structural Heart Disease.

Treatment for ventricular tachycardia (VT) generally includes 1 or more of the following options: antiarrhythmic therapy, an implantable cardioverter-defibrillator and/or catheter ablation. Catheter ablation is performed with an electroanatomic mapping system to define the heart's 3D anatomy, as well as regions of scar. Radiofrequency energy is then applied to areas of abnormal substrate within which are located channels critical to the VT circuit. Cardiac magnetic resonance (CMR) imaging is a non-invasive modality that provides high-resolution images of cardiac structure and function. CMR has become a very useful tool for sudden cardiac death risk stratification and to facilitate successful radiofrequency ablation of VT in patients with abnormal cardiac substrate. The role of CMR in the management and treatment of VT in patients with structural heart disease is reviewed.

Precordial QRS amplitude ratio predicts long-term outcome after catheter ablation of electrical storm due to ventricular tachycardias in patients with arrhythmogenic right ventricular cardiomyopathy

BackgroundRadiofrequency catheter ablation is currently considered as the therapeutic option of choice in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and recurrent ventricular tachycardia (VT). MethodsThis study intended to assess the long-term outcome of catheter ablation in patients with ARVC and electrical storm. The specific objective was to assess the relationship between precordial QRS amplitude ratio and outcome of catheter ablation in these patients. ResultsTwenty-eight patients (19 men, age 52.3±14.2years) underwent 48 catheter ablation procedures (range 1–6, six epicardial). During a mean follow-up of 18.7±15.1months, 13 patients (46.5%) experienced VT recurrence. Age >50years and ∑QRSmvV1–V3/∑QRSmvV1–V6≤0.48 but not right ventricular size and acute ablation outcome were associated with VT recurrence during the follow up. ConclusionAge >50years and ∑QRSmvV1–V3/∑QRSmvV1–V6≤0.48 predict recurrence of VT after successful radiofrequency catheter ablation of VT in patients with ARVC and electrical storm.

Heart Rythm Society expert consensus statement on electrophysiology laboratory standards: process, protocols, equipment, personnel, and safety.

ABBREVIATIONS CIED = cardiovascular implantable electronic device; CT=computed tomography; EP=electrophysiology; FDA= U.S. Food and Drug Administration; ICD=implantable cardioverterdefibrillator; MRI = magnetic resonance imaging; QA = quality assurance; QI = quality improvement; RF = radiofrequency; VT = ventricular tachycardia (Heart Rhythm 2014;11:e9–e51)

Ventricular tachycardia mapping and ablation in arrhythmogenic right ventricular cardiomyopathy/dysplasia: Lessons Learned.

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is primarily believed to be an inherited cardiomyopathy that subsequently results in significant myocardial fibrosis. The arrhythmogenic consequences that result from the development of fibrosis are similar to other nonischemic cardiomyopathies, but the unique endocardial-epicardial disease process of ARVC/D requires a specialized approach for arrhythmia treatment in the electrophysiology laboratory. Although the association between ARVC/D and development of ventricular arrhythmias has become increasingly clear over the last 2 decades, our understanding of the arrhythmia mechanisms, underlying electrophysiologic substrate, and treatment strategies were significantly limited. Prospective studies performed in the electrophysiology laboratory allowed detailed characterization of the electrophysiologic and electroanatomic substrate underlying ventricular tachycardia in patients with ARVC/D. This has allowed clinician scientists to better characterize the arrhythmia mechanism and develop the necessary strategies to perform successful catheter ablation. Early in this experience, catheter ablation was considered a limited and largely unsuccessful treatment for patients experiencing painful and recurrent defibrillator therapy. Through our increased understanding of the disease process, catheter ablation has evolved to become an effective and preferred therapy for a majority of these patients. Our understanding of the disease and necessary approaches to provide successful treatment continues to evolve as the clinical experience grows. This article will review these important insights from the electrophysiology laboratory and how application of this knowledge has facilitated the development of a methodical approach to successfully perform ventricular tachycardia ablation in patients with ARVC/D.

New Ablation Technologies and Techniques.

Catheter ablation is an established treatment strategy for a range of different cardiac arrhythmias. Over the past decade two major areas of expansion have been ablation of atrial fibrillation (AF) and ventricular tachycardia (VT) in the context of structurally abnormal hearts. In parallel with the expanding role of catheter ablation for AF and VT, multiple novel technologies have been developed which aim to increase safety and procedural success. Areas of development include novel catheter designs, novel navigation technologies and higher resolution imaging techniques. The aim of the present review is to provide an overview of novel developments in AF ablation and VT ablation in patients with of structural cardiac diseases.

Radio frequency ablation for VT – A cost-effective tool to combat SCD in developing countries

Radio frequency ablation for VT – A cost-effective tool to combat SCD in developing countries

Outcomes in Catheter Ablation of Ventricular Tachycardia in Dilated Nonischemic Cardiomyopathy Compared With Ischemic Cardiomyopathy

Data on the outcomes of ventricular tachycardia (VT) ablation in nonischemic dilated cardiomyopathy (NIDCM) are insufficient. The Heart Center of Leipzig VT (HELP-VT) study was conducted prospectively to compare outcomes after radiofrequency catheter ablation of VT in patients with NIDCM compared with ischemic cardiomyopathy (ICM). Two hundred twenty-seven patients, 63 with NIDCM and 164 with ICM, presenting with sustained VT were ablated with radiofrequency catheter ablation. Noninducibility of any clinical and nonclinical VT was achieved in 66.7% of NIDCM and in 77.4% of ICM patients. Ablation of the clinical VT only was achieved in 18.3% of ICM and in 22.2% of NIDCM patients. There was no statistically significant difference in short-term outcomes between the 2 groups. At the 1-year follow-up, VT-free survival in NIDCM was 40.5% compared with 57% in ICM. In univariate analysis, the hazard ratio for VT recurrence was significantly higher for NIDCM (1.62; 95% confidence interval, 1.12- 2.34; P=0.01). In both the ICM and NIDCM subgroups, procedure failure and incomplete procedural success were independent predictors of VT recurrence. Although the short-term success rates after VT ablation in NIDCM and ICM patients were similar, the long-term outcomes in NIDCM patients were significantly worse. Complete VT noninducibility at the end of the ablation is associated with beneficial long-term outcome in NIDCM. Pursuing compete elimination of all inducible VTs is desirable and may improve the long-term success in NIDCM.

Catheter Ablation of Stable Ventricular Tachycardia Before Defibrillator Implantation in Patients with Coronary Heart Disease (VTACH): An On‐Treatment Analysis

In the Ventricular Tachycardia Ablation in Coronary Heart Disease (VTACH) study, an intention-to-treat approach was used and may have diminished the observed degree of treatment effect. We present a subanalysis of the VTACH study by treatment actually received. The VTACH study was a prospective, open, randomized controlled trial, undertaken in 16 European centers, comparing defibrillator implantation with and without ventricular tachycardia (VT) ablation in patients with stable VT, previous myocardial infarction, and reduced left-ventricular ejection fraction. Of the 52 patients in the ablation group, 7 (13%) did not receive VT ablation and 19% of patients assigned to implantable cardioverter defibrillator (ICD) only treatment group crossed over and had an ablation. The primary endpoint (first recurrence of any documented VT or ventricular fibrillation [VF]) was reached after a median of 19.5 months in the ablation group and 5.9 months in the ICD only group (P = 0.01). Overall, 685 VT/VF events occurred per year of follow-up in 22 patients of the ablation group and 4,986 events in 43 patients of the control group (P = 0.024). In the ICD only group, median numbers of VT/VF episodes were 25 (IQR 5.8-45.3) and 1.5 (IQR 0-24.8) per patient and year before and after crossover (n = 12), respectively. On-treatment analysis of the VTACH study emphasizes the effectiveness of VT ablation in patients receiving ICD treatment because of monomorphic VT post myocardial infarction. VT ablation clearly prolonged time to recurrence of VT/VF episodes and markedly decreased VT/VF burden.

Epicardial substrate mapping for ventricular tachycardia ablation in patients with non-ischaemic cardiomyopathy: a new algorithm to differentiate between scar and viable myocardium developed by simultaneous integration of computed tomography and contrast-enhanced magnetic resonance imaging

During epicardial electroanatomical mapping (EAM), it is difficult to differentiate between fibrosis and fat, as both exhibit attenuated bipolar voltage (BV). The purpose of this study was to assess whether unipolar voltage (UV), BV, and electrogram characteristics (EC) can distinguish fibrosis from viable myocardium and fat during epicardial EAM for ventricular tachycardia (VT) ablation in non-ischaemic cardiomyopathy (NICM). Ten NICM patients (7 males, 56 ± 13 years) with VT underwent epicardial EAM with real-time integration of computed tomography-derived epicardial fat and contrast-enhanced MRI-derived scar. Bipolar voltage (filtered 30-400 Hz), UV (filtered 1-240 Hz), and EC (duration and morphology) were correlated with the presence of fat and scar. At sites devoid of fat, the optimal cutoff values to differentiate between scar and myocardium were 1.81 mV for BV and 7.95 mV for UV. Bipolar voltage, UV, and electrogram duration >50 ms distinguished scar from myocardium in areas covered with <2.8 mm fat (all P < 0.001), but not ≥ 2.8 mm fat. In contrast, electrogram morphology-characteristics could also detect scar covered with ≥ 2.8 mm fat (P = 0.001). A newly developed three-step algorithm combining electrogram morphology, duration, and UV could correctly identify scar with a sensitivity of 75%. Unipolar voltage but not BV could detect intramural scar in the absence of fat. Both BV ≤ 1.81 mV and UV ≤ 7.95 mV are useful for detection of scar during epicardial EAM, in the absence of ≥ 2.8 mm fat. However, EC can be used to detect scar covered with fat. A newly developed algorithm combining UV and EC can differentiate between scar and viable myocardium. Unipolar voltage but not BV could detect intramural scar.

Percutaneous epicardial ventricular tachycardia ablation after noncoronary cardiac surgery or pericarditis

Patients with previous noncoronary cardiac surgery or pericarditis may require epicardial access to facilitate successful ventricular tachycardia (VT) ablation. Percutaneous pericardial access is known to be difficult in these patients owing to the presence of pericardial adhesions. To examine the success and safety of percutaneous pericardial access as well as the ability to map and ablate epicardial VT targets. We studied 10 consecutive patients with prior noncoronary cardiac surgery (8 patients) or prior pericarditis (2 patients) who required epicardial access for VT ablation. Percutaneous pericardial access was achieved by experienced operators, and dense adhesions interfering with catheter mapping were encountered in all patients. Using blunt dissection with a deflected ablation catheter, adhesions were divided over the course of 19-125 minutes (mean 57±38 minutes; median 47 minutes). This dissection allowed for sufficient epicardial mapping in 9 of 10 (90%) patients. The clinical targeted VTs were rendered noninducible in 8 (80%) patients. One patient had 70 cm(3) of bleeding with the initial puncture. No other complications occurred. During a long-term follow-upof 24±27 months (median 13 months),5 patients have remained VT-free. Percutaneous pericardial access for epicardial VT ablation in patients with previous noncoronary cardiac surgery or pericarditis can usually be obtained. However, dense pericardial adhesions are often encountered and may limit the ability to map the entire epicardial space.Typically,appropriate targets can be reached and ablated by disrupting the adhesions with the ablation catheter and/or deflectable sheath, facilitating excellent long-term clinical outcome in half of the patients with no major complications.

Clinical Observations and Outcome of Ventricular Tachycardia Ablation in Patients with Left Ventricular Assist Devices

Ablation of ventricular tachycardia (VT) in patients with left ventricular assist devices (LVAD) is challenging and not well documented. This report describes our experience with endocardial VT ablation in six patients with an LVAD. We retrospectively reviewed the clinical records of LVAD patients who underwent an ablation procedure for refractory VT. A total of eight ablation procedures were performed in six patients who, during the last 2 weeks before the ablation procedure, received a total of 101 appropriate shocks for VT. A closed aortic valve (n = 2) or aortic atheroma (n = 1) required a transseptal catheterization in three of six patients. The apical LVAD cannula served as a VT substrate in two of six patients. VT was eliminated in four patients and markedly reduced in two others. The latter two patients experienced a total of only four implantable cardioverter defibrillator (ICD) shocks during a follow-up of 130 and 493 days. Intravenous antiarrhythmic medications used in five of six patients before ablation were discontinued in all. The ablation procedures permitted hospital discharge in four of six patients. Five patients died during follow-up (228 ± 207 days after the procedure). The cause of death was unrelated to cardiac arrhythmias. One patient is still alive 1,205 days after the procedure. Ablation of VT in LVAD patients is feasible and can result in a markedly decreased VT burden with a reduction of ICD shocks. The subsequent discontinuation of intravenous antiarrhythmic medications may facilitate hospital discharge.

735 Early Success of Ventricular Tachycardia Ablation in Patients With Structural Heart Disease: A Single Centre Experience

735 Early Success of Ventricular Tachycardia Ablation in Patients With Structural Heart Disease: A Single Centre Experience

Cardiac CT: Imaging of and Through Cardiac Devices

For patients with cardiac devices, cardiac computed tomography (CT) remains the mainstay for imaging due to its superior resolution as compared with echocardiography and nuclear studies and no contraindication to metal as with cardiac magnetic resonance imaging. This review focuses on the evaluation and pitfalls of coronary arterial imaging in patients with devices, such as pacemakers, implantable defibrillators, cardiac resynchronization therapy (CRT), as well as complications such as lead perforation and safety concerns of CT interference. We discuss both pre- and post-procedural CRT assessment for coronary venous imaging and pre-procedural myocardial scar assessment to localize regions of scar and peri-infarct zone to facilitate ventricular tachycardia ablation in patients with devices. We describe potential new research on dyssynchrony and integration with myocardial scar and site of latest activation for patients with or being considered for CRT. We detail the utility of CT for the assessment of proper function and complications in patients with left ventricular assist device implantation.

The Role of Preventive Ablation of Ventricular Tachycardia in the Patient with Coronary Artery Disease, Reduced Left Ventricular Function, and a New Implantable Cardioverter Defibrillator Implant.

Most patients referred for ventricular tachycardia (VT) ablation have already suffered multiple therapies for recurrent VT, typically in the form of implantable cardioverter defibrillator (ICD) shocks. Recent landmark trials have looked at these populations and suggest potential usefulness of early, preventive ablation of VT in patients with ischemic cardiomyopathy. In this review the potential role of early VT ablation in patients with ischemic cardiomyopathy, current controversies regarding VT ablation in this population, and ongoing and future research that may further inform clinical decision making regarding optimal timing of ablation in these patients are discussed.

Can We Eliminate Noninducibility by Programmed Stimulation as an Endpoint for Ventricular Tachycardia Ablation in Patients with Structural Heart Disease?

Can We Eliminate Noninducibility by Programmed Stimulation as an Endpoint for Ventricular Tachycardia Ablation in Patients with Structural Heart Disease?

Ventricular tachycardia ablation in implantable cardioverter-defibrillator recipients: a need to catch up with current recommendations

This editorial refers to ‘Current practice of ventricular tachycardia ablation in patients with implantable cardioverter-defibrillators’ by N. Dagres et al. , Europace 2012;14(1):135–137. Patients with structural heart disease are at risk of ventricular tachycardia (VT), a major cause of sudden cardiac death. The lifesaving benefit achieved with implantable cardioverter-defibrillators (ICD) and cardiac resyncronization therapy-defibrillation (CRT-D) devices has resulted in the increasing number of ICD/CRT-D implants. Despite an upward trend, there is still underutilization in relation to current guidelines that may be partly related to lack of centres and trained electrophysiologists. Although the exact number of active devices in Europe is unknown, it is assumed that currently there are ≥400 000 patients with ICD/CRT-D based on implantation rates and an estimated annual mortality rate of 6%.1 However, ICDs do not prevent VT and in patients in whom an ICD has been implanted for primary prevention, a first episode of VT or ventricular fibrillation (VF) occurs in 35% within 3 years with a 55% risk of subsequent device therapies;2 if the device has been implanted for secondary prevention after one episode of VT/VF, 33–69% of patients receive at least one appropriate ICD therapy within 2 years.3,4 Of importance, monomorphic VT accounts for 83–93% of all device-treated episodes.2,5,6 Although adjustment of arrhythmia detection and anti-tachycardia pacing can reduce the proportion of VTs treated with shocks, up to 21% of all monomorphic VT in 10–13% patients still necessitates shocks5,6 which have an important impact on quality of life. In addition, in patients with heart failure two or more than two appropriate shocks were associated with an eight-fold increased risk of death.7 Antitachycardia pacing can be accompanied by (pre-)syncope and followed by a shock if pacing fails; the occurrence of a single …

Current practice of ventricular tachycardia ablation in patients with implantable cardioverter-defibrillators

We performed a survey on current practice of ventricular tachycardia (VT) ablation in patients with implantable cardioverter-defibrillators among the European Heart Rhythm Association Research Network. The main indication for the procedure is the occurrence of multiple shocks or electrical storm, while prophylactic ablation is only rarely performed. The epicardial approach is seldom used and mostly only after failure of endocardial ablation. The main ablation strategy is targeting the clinical VT only by substrate mapping and ablation, and by targeting fractionated potentials with utilization of modern electroanatomical mapping systems. Still, a considerable number of centres frequently perform the procedure using conventional mapping catheters only.

Ventricular Tachycardia Ablation in Patients with HeartMate II Left Ventricular Assist Devices: Rhythm Still Matters in the Bionic Age

Ventricular Tachycardia Ablation in Patients with HeartMate II Left Ventricular Assist Devices: Rhythm Still Matters in the Bionic Age

Ventricular Tachycardia Ablation Remains Treatment of Last Resort in Structural Heart Disease: Argument for Earlier Intervention

Despite advances in ablation of ventricular tachycardia (VT), recognized toxicity of amiodarone, and potential harm of implantable cardioverter defibrillator (ICD) shocks, there appears to be reluctance to pursue catheter ablation. We tested the hypothesis that patients with structural heart disease and VT are referred late for ablation and may have worse outcomes as a result. Consecutive patients with VT and structural heart disease referred to a single center, between January 2008 and April 2009 were studied. Patients with prior VT ablations were excluded. Late referrals were defined as those with 2 or more episodes of VT, separated by at least 1 month. Ninety-eight consecutive patients were analyzed. Ninety-six percent of patients had an ICD implanted prior to ablation, 58% were in VT storm and 67% taking ≥400 mg daily of amiodarone or amiodarone intolerant (10%). Thirty-six patients fit the definition of early referral and 62 late. Overall acute procedural success was achieved in 89%. Amiodarone dose decreased from a mean and median of 559 and 400 mg daily preablation to 98 and 0 postablation (P < 0.01). Mean and median VT episodes decreased from 17 and 6 in the month preceding ablation to 1 and 0 in the 6 months following ablation (P < 0.01). In Kaplan-Meier analysis, the early referral group had superior 1-year VT free survival (P = 0.01). VT ablation is frequently reserved for patients receiving recurrent ICD shocks despite high dose amiodarone. Stronger consideration should be given to earlier referral for VT ablation in patients with structural heart disease.

Isolated Potentials and Pace‐Mapping as Guides for Ablation of Ventricular Tachycardia in Various Types of Nonischemic Cardiomyopathy

In patients with prior infarction, isolated potentials (IPs) during sinus rhythm reflect fixed scar and often indicate sites critical for ventricular tachycardia (VT). The purpose of this study was to determine the value of IPs in conjunction with pace-mapping to guide VT ablation in patients with various types of nonischemic cardiomyopathy. Mapping and ablation of VT were performed in 35 consecutive patients (26 men, age 55 ± 13 years, ejection fraction 0.31 ± 0.14) with VT and various etiologies of nonischemic cardiomyopathy. Pace-mapping was performed at sites with low voltage. Radiofrequency energy was delivered at sites with concealed entrainment or matching pace-maps. One hundred ninety-five VTs (mean cycle length 363 ± 88 ms) were induced. Sites with prespecified ablation criteria displaying IPs during sinus rhythm were recorded in 21 of 35 patients (60%, IP-positive). In these patients, a total of 216 sites meeting prespecified ablation criteria were identified and 146 of 216 sites (68%) displayed IPs. Fifteen of 21 IP-positive patients (71%) no longer had inducible VT after ablation. In 14 of 35 patients, no sites with IPs where prespecified ablation criteria were met were identified (IP-negative) despite combined endocardial and epicardial mapping in 7 of 14 patients. Only 1 of 14 IP-negative patients (7%) no longer had inducible VT at the end of the ablation procedure. During a mean follow-up of 18 ± 13 months, 14 of 21 IP-positive patients (67%) remained arrhythmia-free, compared to 1 of 14 IP-negative patients (7%; P < 0.01). Half of the IP-negative patients had major adverse events due to recurrent arrhythmias, compared to none in IP-positive patients. IPs in conjunction with pace-mapping are helpful for identifying critical isthmus areas for ablation of VT in patients with various types of nonischemic cardiomyopathy. Patients with nonischemic cardiomyopathy in whom the arrhythmogenic substrate is characterized by IPs have a more favorable outcome than patients in whom IPs are absent.