Independent Predictor Of Ventricular Arrhythmias Research Articles

Using the 3D architecture of scar to predict life-threatening ventricular arrhythmias, still a long way to go

Abstract Background Late gadolinium enhancement (LGE) has been proposed as an independent predictor of ventricular arrhythmias. Purpose The purpose of this study was to assess if myocardial scar characterization could enhance the risk stratification for life-threatening arrhythmias and sudden cardiac death (SCD). Methods We included patients with an indication for ICD or CRT-D implantation who underwent cardiac magnetic resonance for clinical proposes since February/2018 and in whom a 3D-LGE dataset was obtained. Patients with channelopathies (n=2) or inappropriate imaging quality (imaging artifacts; n=7) were excluded. Scar characterization using ADAS software was performed in 3D-LGE datasets in all but 16 patients, where 2D datasets were used. The primary endpoint was the composite of appropriate ICD therapy (classified as ATP or shock), sustained ventricular tachycardia or SCD. Results A total of 116 patients were analysed (mean age 66 ± 14 years; 81% male; mean LVEF 34 ± 14%; 74 patients with ischemic and 42 with non-ischemic cardiomyopathy; 40 patients received a device in the setting of secondary prevention). During a median follow-up of 2.3 years (IQR 1.3 – 3.3 years) there were 23 events (18 appropriate ICD therapies [9 shocks and 9 ATP], 3 episodes of VT under the threshold for ICD therapy and 2 SCD). No statistically significant differences were found between patients with or without events in terms of scar mass, border zone (BZ) mass, BZ channels (BZC), BZC mass, number of channels detected, and scar heterogeneity (BZ mass / scar mass ratio) - all p values > 0.2 – Figure. Restricting the analysis to only primary prevention cases yielded similar results. Overall, 26 patients did not show any channel. Four of these (all with non-ischemic LGE) experienced an arrhythmic event, yielding a negative predictive value of 83% (95% CI 64-93%) for the absence of channels. Conclusion In this cohort with still relatively limited follow-up duration, no single parameter reflecting scar tissue characterization was able to predict appropriate device therapies or sudden cardiac death.

Myocardial edema measured by T2 mapping is an independent predictor of ventricular arrhythmias in hypertrophic cardiomyopathy

Abstract Introduction Clinical outcome of patients with hypertrophic cardiomyopathy (HCM) largely depends on ventricular arrhythmias. Parametric T2 mapping from Cardiac MRI (CMR) was found to be a measure of myocardial edema. We sought to study whether elevated T2 values on CMR in patients with hypertrophic cardiomyopathy (HCM) might predict ventricular arrhythmias (VA) and adverse clinical outcome. Methods Consecutive patients with HCM (n = 59) and healthy volunteers (n = 21) underwent 3 Tesla CMR. T2 mapping values were independently analyzed by 2 independent readers and presented using a 16-segment AHA model. VA was recorded by 24-hour Holter monitoring and/or during exercise stress test. Composite outcome was defined as ventricular tachycardia (VT) per Holter and/or ergometry, admission due to arrhythmias, ICD insertion and all-cause mortality. Statistical analysis was a t-test for VA and multi-variant logistic regression model adjusted for age and gender. Results Septal and apical variants of HCM were found in 42 and 17 patients, respectively. We found good interobserver agreement in T2 values (ICC=0.92, 95% CI 0.86 - 0.96, p value <0.001). The 3rd tertile of T2 values (48 ± 8 msec) was significantly associated with VA 92% vs. 57 and 40% in lower tertiles, p = 0.02. Logistic regression analysis showed the 3rd tertile was an independent predictor of composite outcome (VT per Holter and/or ergometry, admission due to arrhythmias, ICD and all-cause mortality) OR 95% CI = 22.8 (1.4 - 361.6), p = 0.026. ROC analysis to find best cut-off of T2 for prediction of outcome showed AUC 0.7 (Figure 1). Conclusion Elevated T2 is an independent predictor of VA and adverse outcome in HMC patients. These results suggest the impact of myocardial edema in myocardial disease activity in HCM.ROC analysis to find best cut-off of T2

Using the 3D architecture of scar to predict life-threatening ventricular arrythmias - still a long way to go

Abstract Funding Acknowledgements Type of funding sources: None. Background Late gadolinium enhancement (LGE) has been proposed as an independent predictor of ventricular arrhythmias. Purpose The purpose of this study was to assess if myocardial scar characterization could enhance the risk stratification for life-threatening arrhythmias and sudden cardiac death (SCD). Methods We included patients with an indication for ICD or CRT-D implantation who underwent cardiac magnetic resonance for clinical proposes since February/2018 and in whom a 3D-LGE dataset was obtained. Patients with channelopathies (n=2) or inappropriate imaging quality (imaging artifacts; n=7) were excluded. Scar characterization using ADAS software was performed in 3D-LGE datasets in all but 5 patients, where 2D datasets were used. The primary endpoint was the composite of appropriate ICD therapy (classified as ATP or shock) or SCD. Results A total of 75 patients were analysed (mean age 63 ± 13 years; 83% male; mean LVEF 31 ± 13%; 50 patients with ischemic and 25 with non-ischemic cardiomyopathy; 14 patients received a device in the setting of secondary prevention). During a median follow-up of 1.4 years (IQR 0.7 – 2.4 years) there were 15 events (12 appropriate ICD therapies [8 shocks and 4 ATP] and 3 SCD). No statistically significant differences were found between patients with or without events in terms of scar mass, border zone (BZ) mass, BZ channels (BZC), BZC mass, number of channels detected, and scar heterogeneity (BZ mass / scar mass ratio) - all p values > 0.2 – Figure. Restricting the analysis to only primary prevention cases yielded similar results. Overall, 11 patients did not show any channel. Two of these experienced an arrhythmic event, yielding a negative predictive value of 80% (95% CI 75-83%) for the absence of channels. Conclusion In this cohort with still relatively limited follow-up duration, no single parameter reflecting scar tissue characterization was able to predict appropriate device therapies or sudden cardiac death.

PO-03-086 USING THE 3D ARCHITECTURE OF SCAR TO PREDICT LIFE-THREATENING VENTRICULAR ARRHYTHMIAS – STILL A LONG WAY TO GO

Late gadolinium enhancement (LGE) has been proposed as an independent predictor of ventricular arrhythmias. The purpose of this study was to assess if myocardial scar characterization could enhance the risk stratification for life-threatening arrhythmias and sudden cardiac death (SCD). We included patients with an indication for ICD or CRT-D implantation who underwent cardiac magnetic resonance for clinical proposes since February/2018 and in whom a 3D-LGE dataset was obtained. Patients with channelopathies (n=2) or inappropriate imaging quality (imaging artifacts; n=7) were excluded. Scar characterization using ADAS software was performed in 3D-LGE datasets in all but 16 patients, where 2D datasets were used. The primary endpoint was the composite of appropriate ICD therapy (classified as ATP or shock), sustained ventricular tachycardia or SCD. A total of 116 patients were analysed (mean age 66 ± 14 years; 81% male; mean LVEF 34 ± 14%; 74 patients with ischemic and 42 with non-ischemic cardiomyopathy; 40 patients received a device in the setting of secondary prevention). During a median follow-up of 2.3 years (IQR 1.3 – 3.3 years) there were 23 events (18 appropriate ICD therapies [9 shocks and 9 ATP], 3 episodes of VT under the threshold for ICD therapy and 2 SCD). No statistically significant differences were found between patients with or without events in terms of scar mass, border zone (BZ) mass, BZ channels (BZC), BZC mass, number of channels detected, and scar heterogeneity (BZ mass / scar mass ratio) - all p values > 0.2 – Figure. Restricting the analysis to only primary prevention cases yielded similar results. Overall, 26 patients did not show any channel. Four of these (all with non-ischemic LGE) experienced an arrhythmic event, yielding a negative predictive value of 83% (95% CI 64-93%) for the absence of channels. In this cohort with still relatively limited follow-up duration, no single parameter reflecting scar tissue characterization was able to predict appropriate device therapies or sudden cardiac death.

Genetic testing in children with Brugada syndrome: results from a large prospective registry.

A pathogenic/likely pathogenic (P/LP) variant in SCN5A is found in 20-25% of patients with Brugada syndrome (BrS). However, the diagnostic yield and prognosis of gene panel testing in paediatric BrS is unclear. The aim of this study is to define the diagnostic yield and outcomes of SCN5A gene testing with ACMG variant classification in paediatric BrS patients compared with adults. All consecutive patients diagnosed with BrS, between 1992 and 2022, were prospectively enrolled in the UZ Brussel BrS registry. Inclusion criteria were: (i) BrS diagnosis; (ii) genetic analysis performed with a large gene panel; and (iii) classification of gene variants following ACMG guidelines. Paediatric patients were defined as ≤16 years of age. The primary endpoint was ventricular arrhythmias (VAs). A total of 500 BrS patients were included, with 63 paediatric patients and 437 adult patients. Among children with BrS, 29 patients (46%) had a P/LP variant (P+) in SCN5A and no variants were found in 34 (54%) patients (P-). After a mean follow-up of 125.9 months, 8 children (12.7%) experienced a VA, treated with implanted cardioverter defibrillator shock. At survival analysis, P- paediatric patients had higher VA-free survival during the follow-up, compared with P+ paediatric patients. P+ status was an independent predictor of VA. There was no difference in VA-free survival between paediatric and adult BrS patients for both P- and P+. In a large BrS cohort, the diagnostic yield for P/LP variants in the paediatric population is 46%. P+ children with BrS have a worse arrhythmic prognosis.

A New Scoring System for Predicting Ventricular Arrhythmia Risk in Patients with Acute Myocardial Infarction.

In this study, a risk score for ventricular arrhythmias (VA) were evaluated for predicting the risk of ventricular arrhythmia (VA) of acute myocardial infarction (AMI) patients. Patients with AMI were divided into two sets according to whether VA occurred during hospitalization. Another cohort was enrolled for external validation. The area under the curve (AUC) of receiver operating characteristic (ROC) was calculated to evaluate the accuracy of the model. A total of 1493 eligible patients with AMI were enrolled as the training set, of whom 70 (4.7%) developed VA during hospitalization. In-hospital mortality was significantly higher in the VA set than in the non-VA set (31.4% vs 2.7%, P=0.001). The independent predictors of VA in patients with AMI including Killip grade ≥3, STEMI patients, LVEF <50%, frequent premature ventricular beats, serum potassium <3.5 mmol/L, type 2 diabetes, and creatinine level. The AUC of the model for predicting VT/VF in the training set was 0.815 (95% CI: 0.763-0.866). A total of 1149 cases were enrolled from Xuzhou Center Hospital as the external validation set. The AUC of the model in the external validation set for predicting VT/VF was 0.755 (95% CI: 0.687-0.823). Calibration curves indicated a good consistency between the predicted and the observed probabilities of VA in both sets. We have established a clinical prediction risk score for predicting the occurrence of VA in AMI patients. The prediction score is easy to use, performs well and can be used to guide clinical practice.

Cardiac magnetic resonance imaging predictors of ventricular arrhythmia in mid-cavity obstructive hypertrophic cardiomyopathy

Abstract Background/Introduction Left ventricular (LV) mid-cavity obstruction (LVMCO) in hypertrophic cardiomyopathy (HCM) is an uncommon phenotypic feature predisposed to the formation of myocardial fibrosis and apical aneurysms (LVAA). These features may be independently proarrhythmic, and LVAA is considered a class 2a indication for implantable cardioverter defibrillator (ICD) in current US, but not European guidelines for the primary prevention of sudden cardiac death (SCD). Cardiac magnetic resonance (CMR) imaging is the preferred modality for detecting these and other phenotypic features critical to SCD risk assessment. Purpose To assess the ability of CMR imaging parameters to predict occurrence of non-sustained ventricular tachycardia (NSVT) in HCM patients with Doppler-derived evidence of LVMCO. Methods Multi-modality imaging records were retrospectively assessed to identify HCM patients with Doppler-LVMCO and CMR scans. CMR images were assessed by an investigator blinded to clinical status. Late gadolinium enhancement (LGE) was quantified using the full-width, half-maximum technique. CMR imaging parameters were assessed for predictive ability using Cox proportional hazards during univariate and multivariate analyses, accounting for time to event (NSVT or censorship of follow-up). Results The study cohort included 58 patients (57±11 years, 74% male) with a median follow-up of 6.2 (IQR 4.3) years. Mean mid-cavity gradient was 33±23 mmHg. NSVT was detected in 27/58 (47%) patients, was 4 beats or longer in 23/27 (85%) and was monomorphic in 21/27 (77%). On univariate analysis, predictors of NSVT during follow-up include LV mass index (HR 1.02, 95% CI 1.00–1.04, p=0.03), LGE in grams (HR 1.04, 95% CI 1.01–1.06, p=0.005), and LVAA (HR 2.57, 95% CI 1.14–5.79, p=0.023). After multivariate adjustment (Table 2), none were significantly associated. Conclusions In LVMCO, magnitude of LV hypertrophy, extent of LGE and the presence of an apical aneurysm may not be independent predictors of ventricular arrhythmias. SCD algorithms based on qualitative assessments of these features may overestimate risk. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): National Institute of Health Research (NIHR)

Looking for appropriate criterias for SCD prevention: prognostic role of MRI in patients with nonischemic ventricular arrhythmias

Abstract Background Currently left ventricular ejection fraction (LVEF) remains the only indicator for identifying candidates for implantable cardioverter-defibrillator (ICD)therapy for the primary prevention of sudden cardiac death (SCD). However the majority of patients suffering SCD have a preserved LVEF and some of them with poor LVEF do not benefit from ICD therapy. Late gadolinium enhancement (LGE) on cardiac-MRI (CMR) has been proposed as an independent predictor of ventricular arrhythmias. Limited data exist on the role and methods of LGE quantification in patients with a nonischemic ventricular arrhythmias. Purpose The goal of this study is to explore whether theextent of LGE would improve risk stratification in patients with a nonischemic ventricular arrhythmias with an indication for implantable cardioverter-defibrillator (ICD) therapy for the primary or secondary prevention of SCD. Methods Fifty six patients with a nonischemic ventricular arrhythmias underwent LGE-CMR prior to ICD implantation for primary and secondary prevention of SCD. LGE extent was quantified using both the full-width half-maximum (FWHM) andthe standard deviation–based (2-SD) method. The primary endpoint was appropriate ICD discharge for sustained ventricular tachyarrhythmia. Results During a median follow-up of 18 [11,5–26,0] months the primary endpoint occurred in 22 patients. The median percentage of LV myocardium fibrosis assessed by the 2-SD method was 9,8 [6,0–18,8]%, while for the FWHM method it was 5,1 [3,0–10,6]% (p&amp;lt;0,001). Intra-observer and inter-observer variability of the FWHM technique was excellent, intraclass correlation coefficients (ICC) 0,97 (95% CI: 0,92–0,99) for intraobserver variability and 0,95 (95% CI: 0,85–0,98) for interobserver variability. The ICC for the 2-SD method were lower: 0,92 (95% CI: 0,76–0,97) and 0,90 (95% CI: 0,69–0,96), for intra- and interobserver variability, respectively. By Cox univariate regression analysis, past syncope, HR: 3,14; (CI: 1,28–7,73), past sustained VT, HR: 8,24; (CI: 2,43–27,96), the presence of LBBB before implantation cardiac resynchronization therapy defibrillator (CRT-D), HR: 0,22; (CI: 0,05–0,96) as well as extent of LGE, HR: 1,067; per 1% increase in the extent of LGE, (CI: 1,029–1,107) demonstrated the strongest association with the appropriate ICD discharge. In multivariate regression analysis, the history of sustained VT, HR: 9,17; (CI: 2,60–32,38; p=0,001) and the value of the extent of LGE, HR: 1,081; per 1% increase in volume of LGE, (CI: 1,034–1,131; p=0,001) demonstrated an independent association with the appropriate ICD discharge. Conclusions FWHM is the optimal semi-automated quantification method in patients with nonischemic ventricular arrhythmias, demonstrating the highest technical consistency. LGE extent is an independent predictor of adverse outcomes in patients with nonischemic ventricular arrhythmia and may have an important role in risk stratification. Funding Acknowledgement Type of funding sources: None. LGE QuantificationEvent-Free Survival

B-PO03-165 MEAN SCAR ENTROPY PREDICTS VENTRICULAR ARRHYTHMIAS EVENTS IN HYPERTROPHIC CARDIOMYOPATHY USING LATE GADOLINIUM ENHANCEMENT CARDIAC MAGNETIC RESONANCE

Ventricular arrhythmias (VAs) is associated with sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). Previous studies have found late gadolinium enhanced (LGE) on cardiac magnetic resonance (CMR)was independently associated with VAs in HCM. Risk stratification of VAs remains complex and LGE is present in the majority of HCM patients. This study was to determine whether the LGE by CMR derived entropy within the scar and the left ventricular (LV) myocardium predicts VAs in HCM. Consecutive HCM patients with scar by LGE-CMR were included. Routine left ventricular function parameters including LV ejection fraction (LVEF) and %LGE defined as percentage of LGE to LV mass (%LGE) using software CVI 42. The scar heterogeneity, quantified by entropy within the scar and LV myocardium was derived. The presence of VAs was defined as previous aborted cardiac arrest, documented sustained ventricular tachycardia (VT) and non-stained VT (nsVT) by Holter or implantable cardiac devices (ICD) monitoring. A total of 68 HCM patients (54.6 ±14.3 years, 69.1% male, LVEF 67.2 ±12.9 %) with LGE CMR were enrolled with a median follow-up of 25 (IQR 13-13) months. Thirty-one patients in VAs group and 37 patients in No-VAs group were included. From multivariable analysis, higher entropy of the scar (Hazard ratio [HR] 2.682;95% confidence interval [CI]:1.022 to 7.037; P=0.039) was independently associated with VAs, after adjusting for LVEF, %LGE, the LV maximal wall thickness (MWT) and the left atrium (LA) diameter. High entropy within the scar was an independent predictor of VAs and may indicate an arrhythmogenic scar. It seemed to be valuable for assessing the clinical status of VAs in HCM patients.

Sex-Specific Ventricular Arrhythmias and Mortality in Cardiac Resynchronization Therapy Recipients.

The study goal was to examine whether there are sex-related differences in the incidence of ventricular arrhythmias and mortality in CRT-defibrillator (CRT-D) recipients. Few studies have evaluated sex-related benefits of cardiac resynchronization therapy (CRT). Moreover, data on sex-related differences in the occurrence of ventricular tachyarrhythmias in this population are limited. A multicenter retrospective study was conducted in 460 patients (355 male subjects and 105 female subjects) from the UMBRELLA (Incidence of Arrhythmia in Spanish Population With a Medtronic Implantable Cardiac Defibrillator Implant) national registry. Patients were followed up through remote monitoring after the first implantation of a CRT-D during a median follow-up of 2.2 ± 1.0 years. Sex differences were analyzed in terms of ventricular arrhythmia-treated incidence and death during the follow-up period, with a particular focus on primary prevention patients. Baseline New York Heart Association functional class was worse in women compared with that in men (67.0% of women in New York Heart Association functional class III vs. 49.7% of men; p=0.003), whereas women had less ischemic cardiac disease (20.8% vs. 41.7%; p<0.001). Female sex was an independent predictor of ventricular arrhythmias (hazard ratio: 0.40; 95% confidence interval: 0.19 to 0.86; p=0.020), as well as left ventricular ejection fraction and nonischemic cardiomyopathy. Mortality in women was one-half that of men, although events were scarce and without significant differences (2.9% vs. 5.6%; p=0.25). Women with left bundle branch block and implanted CRT have a lower rate of ventricular tachyarrhythmias than men. All-cause mortality in patients is, at least, similar between female and male subjects.

Usefulness of late gadolinium enhancement cardiac magnetic resonance to predict appropriate therapies in implantable cardioverter defibrillator patients in primary prevention

Abstract Background The scar and the amount of border zone measured by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) has been proposed as an independent predictor of ventricular arrhythmias in patients with ischemic and non-ischemic cardiomyopathy. However, at the present time, the guidelines are based only on the ejection fraction to recommend an implantable cardioverter defibrillator (ICD) in primary prevention, and only a minority of these patients receive appropriate therapies. So, prevention needs to be improved. Purpose To identify predictors of appropriate therapies in patients with a primary prevention ICD using cardiac magnetic resonance imaging and a dedicated software (ADAS-3D) to characterize the scar. Methods Patients who underwent a LGE-MR prior to ICD implantation in primary prevention were retrospectively included. Clinical and cardiac imaging characteristics were collected. The myocardium was segmented with ADAS-3D software in 10 layers (from endocardium to epicardium). The scar, border zone, core and conducting channels were automatically measured in grams by the software. Results Since 2008 to 2017, 206 patients were included. Mean age was 67±28 years, 80% men, mean ejection fraction 26%±9, 52% with ischemic cardiomyopathy and 48% non-ischemic. The primary endpoint was appropriate therapies and/or sudden cardiac death (SCD). Median follow-up was 46.33 months. 46 patients (22%) reached the primary endpoint. Greater scar mass (36.05 grams vs 21.5 grams; HR 1.04; 95% CI (1.03–1-05), p&amp;lt;0.001), core mass (9.8 grams vs 5.6 grams; HR 1.06; 95% CI (1.04–1-09), p&amp;lt;0.001), border zone mass (26.2 grams vs 15.9 grams; HR 1.05; 95% CI (1.04–1-09), p&amp;lt;0.001) and channel mass (3.0 grams vs 1.6 grams; HR 1.15 95% CI (1.06–1.25), p&amp;lt;0.001) were associated with appropriate therapies and SCD. A border zone mass &amp;gt;5.3 grams was independently associated with the primary endpoint (HR: 4.77; 95% CI (1.15–19.73), p=0.03). Conclusions The amount of border zone, core and channel mass measured by LGE-MR and ADAS software are independent predictors of appropriate therapies and SCD in patients with ICD in primary prevention. Scar characterization Funding Acknowledgement Type of funding source: None

P575Usefulness of late gadolinium enhancement cardiac magnetic resonance to predict appropriate therapies in implantable cardioverter defibrillator patients in primary prevention

Abstract Funding Acknowledgements No funding acknowledgements OnBehalf VT and sudden cardiac death Background The scar and the amount of border zone measured by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) has been proposed as an independent predictor of ventricular arrhythmias in patients with ischemic and non-ischemic cardiomyopathy. However, at the present time, the guidelines are based only on the ejection fraction to recommend an implantable cardioverter defibrillator (ICD) in primary prevention, and only a minority of these patients receive appropriate therapies. So, prevention needs to be improved. Purpose To identify predictors of appropriate therapies in patients with a primary prevention ICD using cardiac magnetic resonance imaging and a dedicated software (ADAS-3D) to characterize the scar. Methods All consecutive patients who underwent a LGE-MR prior to ICD implantation in primary prevention were prospectively included. Clinical and cardiac imaging characteristics were collected. The myocardium was segmented with ADAS-3D software in 10 layers (from endocardium to epicardium). The scar, border zone, core and conducting channels were automatically measured in grams by the software. Results Since 2008 to 2017, 206 patients were included. Mean age was 67 +/- 28 years, 80% men, mean ejection fraction 26%+/-9, 52% with ischemic cardiomyopathy and 48% non-ischemic. The primary endpoint was appropriate therapies and/or sudden cardiac death (SCD). Median follow-up was 46,33 months. 46 patients (22%) reached the primary endpoint. Greater scar mass (36,05 grams vs 21,5 grams; HR 1.04; 95% CI (1.03-1-05), p &amp;lt;0.001), core mass (9,8 grams vs 5,6 grams; HR 1.06; 95% CI (1.04-1-09), p &amp;lt;0.001), border zone mass (26,2 grams vs 15,9 grams; HR 1.05; 95% CI (1.04-1-09), p &amp;lt;0.001) and channel mass (3,0 grams vs 1,6 grams; HR 1.15 95% CI (1.06-1.25), p &amp;lt;0.001) were associated with appropriate therapies and SCD. A border zone mass &amp;gt;5.3 grams was independently associated with the primary endpoint (HR: 4.77; 95% CI (1.15-19.73), p = 0.03). Conclusions The amount of border zone, core and channel mass measured by LGE-MR and ADAS software are independent predictors of appropriate therapies and SCD in patients with ICD in primary prevention. Abstract Figure. Scar characterization

Revascularization of coronary chronic total occlusions in an infarct‐related artery and recurrence of ventricular arrhythmias among patients with secondary prevention implantable cardioverter defibrillator

To evaluate whether the revascularization of a coronary chronic total occlusion in an infarct-related artery (IRACTO) may be associated with lower recurrence of ventricular arrhythmias (VA) among patients with a secondary prevention implantable cardioverter defibrillator (ICD). IRACTO is increasingly recognized as an independent predictor of VA. It is unknown whether IRACTO revascularization can reduce the burden of VA. Multicenter observational cohort study that included consecutive patients with prior myocardial infarction and secondary prevention ICD. The primary endpoint was any appropriate ICD therapy. Among the 460 patients included, 269 (58%) had at least one IRACTO at the coronary angiogram performed before ICD implantation; of these, 20 (7%) had their IRACTO successfully revascularized (IRACTO-R) afterwards. During a median follow-up of 48 months, 229 patients (49%) had at least one appropriate ICD therapy. Patients with IRACTO not revascularized (IRACTO-NR) had the highest incidence of ICD therapies (65%) while patients with IRACTO-R had the lowest (10%, p < .001). In the entire cohort, IRACTO-NR was an independent predictor of appropriate ICD therapies (HR 2.85, p < .001) and appropriate ICD shocks (HR 2.94, p < .001). Among patients with IRACTO at baseline, IRACTO-R was independently associated with a marked reduction of appropriate ICD therapies (HR 0.12, p = .002) and appropriate ICD shocks (HR 0.21, p = .03). In patients with prior myocardial infarction and secondary prevention ICD, IRACTO revascularization was independently associated with a markedly lower incidence of appropriate ICD therapies and shocks. These results should be corroborated by larger prospective studies.

Heart rate variability reduction as a non-ivasive predictor of ventricular tachyarrythmias in patients with coronary artery disease

Highlights. The implantation of cardioverter-defibrillator is the most effective method for preventing sudden cardiac death. However, almost 25% patients have normally functioning CD at the 5-years follow-up. This has necessitated the search for new non-invasive diagnostic methods for detecting patients at high risk of ventricular tachyarrhythmias. Aim. To evaluate whether the estimated heart rate variability may be used as a predictor for ventricular arrhythmias (VTA) in patients with coronary artery disease. Methods . 51 patients (mean age of 65.4±8.4 year; 41 male patients (80,3%)) with coronary artery disease (CAD) and indications for cardioverter-defibrillator (ICD) implantation were included to the study. The 6-minute walk distance, echocardiography, heart rate variability (HRV) were assessed and compared between the groups. The statistical analysis was performed using the Statistica 10.0, StatSoft (USA) and MedCalc statistical software (USA). Results . 43 (84.3%) patients with VTA within the 18-months follow-up were assigned to Group 1, and 8 (15.7%) patients without VTA during the 18-month follow-up were assigned to Group 2. The univariate ROC-analysis showed that a reduction in the average NN interval less than 1130 ms (p = 0.0282), root mean square of successive differences less than 18 ms (p = 0.0037) and high frequency spectral component less than 770 ms (p = 0.0001) contributed to the onset of of VTA. Multivariate ROC-analysis demonstrated that the end-diastolic index (p = 0.0185) and standard deviation of NN interval (p = 0.0370) were independent predictors of VTA. An increase of the VTA predictive index (calculated according to the presented predictive model) by &gt;0.5613 suggested the onset of VTA (AUC = 0.927; p = 0.0001). Conclusion . Reduced HRV may be a non-invasive VTA predictor in patients with CAD. The combined use of echocardiography and HRV analysis allows identifying a group of patients with high risk of sudden cardiac death.

Risk Stratification in Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia Without an Implantable Cardioverter-Defibrillator.

The purpose of this study was to identify clinical factors associated with arrhythmic events and sudden cardiac death (SCD), and to evaluate the prognostic value of electrophysiological study (EPS) in arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) patients without implantable cardioverter-defibrillators (ICDs). ARVC/D is an inherited cardiomyopathy characterized by a risk of SCD. Few studies have evaluated predictive factors of ventricular arrhythmias (VAs) in patients without ICDs. Between 2000 and 2010, all consecutive patients with ARVC/D without ICDs and with EPS at diagnosis were enrolled. Patients that received an ICD during follow-up were censored at the date of implantation, and in that case, only VAs that occurred before ICD implantation were analyzed. Risk factors for any VA event were determined by Cox regression. Patients that only experienced SCD or aborted cardiac arrest (ACA) were reported. A total of 137 consecutive patients (78% male) diagnosed with ARVC/D without ICD were enrolled. 31% had sustained ventricular tachycardia at diagnosis. After mean follow-up of 42 ± 31 months, 19 patients experienced an episode of sustained VA and 5 patients experienced a SCD/ACA. No event occurred in asymptomatic patients. Left ventricular ejection fraction≤50% (p= 0.024), positive EPS (p= 0.017), and physical activity >6 h/week (p= 0.025) were independently associated with occurrence of VAs. SCD/ACA exclusively occurred in male probands with definite diagnosis and syncope. In this cohort of ARVC/D patients without ICD, left ventricular ejection fraction≤50%, positive EPS, and physical activity >6 h/week were independent predictors of VAs, whereas asymptomatic patients at diagnosis were at low risk. EPS predicted all VAs but had limited value to predict SCD/ACA.

Meta-Analysis of Risk of Ventricular Arrhythmias and All-Cause Mortality in Patients With Chronic Total Occlusion of a Coronary Artery and/or Implantable Cardioverter-Defibrillator

Implantable cardioverter-defibrillator (ICD) has been increasingly used to prevent sudden death in patients with high risk of ventricular arrhythmias (VAs). Chronic total occlusion (CTO) is a severe condition of coronary artery disease. However, the prognostic impact of CTO in ICD recipients remains controversial. We systematically searched the PubMed, EMBASE, and Cochrane databases for documents published before October 1, 2017 to identify studies that investigated the prognostic impact of CTO on VAs and all-cause mortality (ACM) in ICD recipients. The effect size was expressed by hazard ratio (HR) and 95% confidence interval (CI). Overall, 6 studies with 1,423 patients were included. We found that CTO independently predicted the occurrence of VAs in the global population (HR 1.77, 95% CI 1.14 to 2.76, p = 0.01). Subgroup analysis revealed that CTO only predicted VAs in patients receiving ICD as secondary prevention (HR 1.96, 95% CI 1.55 to 2.48, p <0.01). However, CTO was not associated with ACM in the global population (HR 1.51, 95% CI 0.99 to 2.32, p = 0.06). Further subgroup analysis still showed no association between CTO and ACM in patients receiving ICD as primary prevention (HR 1.49, 95% CI 0.43 to 5.21, p = 0.53) or secondary prevention (HR 1.56, 95% CI 0.87 to 2.78, p = 0.13). In conclusion, CTO is an independent predictor of VAs in patients with secondary-prevention ICD, but not for ACM. Our study provided additional evidence for improving the risk stratification and management of VAs in ICD recipients.

Usefulness of Speckle Tracking Strain Echocardiography for Assessment of Risk of Ventricular Arrhythmias After Placement of a Left Ventricular Assist Device

Patients with continuous-flow left ventricular assist devices (LVADs) are at elevated risk of developing ventricular arrhythmias (VA), which can result in right ventricular dysfunction and abnormal LVAD function. Predictors of postoperative VA after LVAD placement are unclear. We hypothesized that global left ventricular circumferential strain (LVCS), a marker of transmural impairment in myocardial function, would independently predict postoperative VA in patients who underwent LVAD implantation. We studied 98 consecutive patients (57 ± 11 years, 83% men) who underwent HeartMate II axial flow LVAD placement. Speckle tracking-derived global circumferential strain was assessed from mid-left ventricular short-axis images. The primary composite end point was defined as any ventricular tachycardia that required intervention (anti-arrhythmic medication, cardioversion, implantable cardioverter defibrillator placement, implantable cardioverter defibrillator shock) or any ventricular fibrillation. A total of 33 patients (34%) experienced the primary end point (median follow-up: 7 months). Reduced LVCS was statistically significantly related to the primary end point (hazard ratio 1.77, 95% confidence interval 1.09 to 2.87 per 1 standard deviation reduction in LVCS, p = 0.02). LVCS above a cut-off value of -9.7% was associated with significantly reduced arrhythmia-free survival (log-rank p = 0.001). In conclusion, global LVCS is an independent predictor of ventricular arrhythmias after LVAD placement.

Clinical Application of the QRS-T Angle for the Prediction of Ventricular Arrhythmias in Patients with the Fontan Palliation

Fontan palliation patients are at risk for ventricular arrhythmias post-operatively. This study aimed to evaluate whether differences in the spatial QRS-T angle can reliably predict ventricular arrhythmias in patients who had undergone Fontan palliation. A total of 117 patients who had theFontan palliation and post-Fontan catheterization were included. Ventricular arrhythmias were identified in nine patients. Measurements of ECG parameters including QRS vector magnitude, QRS duration, corrected QT interval, and spatial peaks QRS-T angles were performed, and compared between those with and without ventricular arrhythmias. The only ECG parameter to distinguish those with versus those without VA was the SPQRS-T angle (p<0.001), which at a cut-off value of 102.9° gave sensitivity, specificity, positive and negative predictive values of 100.0, 57.0, 17.6 and 100.0%, respectively. Only the spatial peaks QRS-T angle differentiated those with and without ventricular arrhythmia development with a univariate HR 1.237 (95% CI 1.021-1.500) and a multivariate HR of 1.032 (1.009-1.056) when catheter measured parameters were taken into account. In Fontan patients, the spatial peaks QRS-T angle is a significant independent predictor of ventricular arrhythmias. Clinical usefulness of this parameter remains to be seen and should be tested prospectively.

Chronic total occlusion of an infarct-related artery: a new predictor of ventricular arrhythmias in primary prevention implantable cardioverter defibrillator patients.

The aim of this article is to evaluate the impact of a coronary chronic total occlusion in an infarct-related artery (IRA-CTO) on the occurrence of ventricular arrhythmias (VAs) in patients implanted with an implantable cardioverter defibrillator (ICD) for primary prevention. The study includes a prospective cohort of 108 consecutive patients with ischaemic cardiomyopathy, in whom an ICD was implanted for primary prevention and a coronary angiography performed before ICD implantation. About 49 patients (45%) had a CTO and 34 (31%) had an IRA-CTO. Patients with IRA-CTO did not differ from the rest of the population in terms of basal characteristics and severity of cardiac disease. Median follow-up was 33 months (interquartile range 46). Infarct-related artery-CTO was associated with higher rates of any VA (53 vs. 26%, P = 0.006) and fast ventricular tachycardia (fast VT, cycle length <300 ms) or ventricular fibrillation (VF) (47 vs. 19%, P = 0.002). At multivariate Cox regression, IRA-CTO was the only independent predictor of any VA [hazard ratio (HR) 3.64, P = 0.002] and fast VT/VF (HR 3.36, P = 0.008). On the contrary, CTO not associated with a prior infarction in their territory did not increase the risk of VA. Infract-related artery-CTO was also an independent predictor of cardiac mortality or heart transplantation (HR 3.46, P = 0.022). In ischaemic patients implanted with an ICD for primary prevention, a CTO associated with a previous infarction in its territory is an independent predictor of VA and, especially, of fast VT/VF, identifying a subgroup of patients with a very high rate of arrhythmic events at follow-up.

Left ventricular markers of mortality and ventricular arrhythmias in heart failure patients with cardiac resynchronization therapy.

AimsCardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure. However, prediction of the outcome remains difficult. We aimed to investigate for echocardiographic predictors of ventricular arrhythmias and fatal outcome and to explore how myocardial function is changed by biventricular pacing in heart failure.Methods and resultsWe prospectively included 170 heart failure patients (66 ± 10 years, New York Heart Association class 2.8 ± 0.5, 48% ischaemic cardiomyopathy) and recorded ventricular arrhythmias and fatal end point defined as death, heart transplantation, or left ventricular assist device implantation during 2 years. Two-dimensional echocardiography was performed before and 6 months after CRT implantation. CRT response was defined as ≥15% reduction in end-systolic volume at 6 months. Speckle-tracking technique was performed to assess longitudinal and circumferential left ventricular function, defined as global longitudinal (GLS) and circumferential strain (GCS), and to assess mechanical dyssynchrony, defined as mechanical dispersion. GLS before CRT was a predictor of fatal end point independently of CRT response [hazard ratio, HR 1.14 (1.02–1.27), P = 0.02]. Patients with GLS better than −8.3% showed event-free survival benefit (log rank, P < 0.001). Mechanical dispersion at 6 months was an independent predictor of ventricular arrhythmias [HR 1.20 (1.06–1.35), P = 0.005]. CRT responders (59%) had improvement of both GLS and GCS.ConclusionIn heart failure patients with CRT, worse longitudinal function before CRT was an important predictor of fatal outcome during 2 years, independently of CRT response. Mechanical dispersion at 6 months was a strong predictor of ventricular arrhythmias. CRT response by reverse remodelling was dependent on improvement of both longitudinal and circumferential function.