Rate Of Ventricular Tachycardia Research Articles

Comparing ventricular tachycardia across the nation: Stratification by different malignancies.

e23151 Background: Cardiac arrhythmias and cancer are prevalent conditions and share common predisposing factors. No studies have assessed VT rates and their outcomes stratified by cancer types. We aim to compare the occurrence of ventricular tachycardia (VT) and its outcomes in different malignancies. Methods: The national readmission database (2016-2020) was queried to identify all-cause admissions for patients with active malignancy of any origin. The study population was divided into six subgroups based on the type of cancer (colorectal, renal, lung, breast, prostate, and hematological). Multivariate regression analysis was utilized for adjusted odds of mortality. A propensity score matching (PSM) model matched malignancy of interest with other malignancies to obtain incidence rates. Results: Among 10.6 million all-cause cancer-related hospitalizations, about 0.8% developed VT. On a propensity-matched analysis & compared to other malignancies, VT had the highest incidence in hospitalizations associated with hematological malignancies (1%), followed by prostate (0.95%), lung (0.9%), renal (0.76%), colorectal (0.75%) & breast (0.50%) malignancies [p < 0.05]. Moreover, cancer hospitalizations complicated by VT were associated with higher mortality. VT was associated with the highest adjusted odds of mortality in renal malignancies (aOR:4.62), followed by breast (aOR:4.60), hematological (aOR:4.44), colorectal (aOR:3.75), prostrate (aOR:3.44), & lung (aOR:3.11) malignancies [p < 0.001]. The rates of 30-day VT-related readmission were highest in hematological malignancies (16.8%), followed by renal (15.9%), lung (15.7%), prostrate (15%), colorectal (14%) & breast (13.9%) malignancies [p < 0.05]. Conclusions: The rate of VT in nationwide hospitalizations among cancer patients was ~ 0.8 %. VT was found to have the highest incidence & readmissions in hematological malignancies, while VT-related mortality was highest in renal malignancies.

Ablation of hemodynamically unstable ventricular tachycardia guided by ultra-high density pacemapping and PASO correlation map, a multi-center clinical trial

Abstract Background Due to hemodynamic instability during ventricular tachycardia (VT), obtaining a complete electroanatomic map is often difficult if not impossible. Pace-mapping has progressed but still lacks precision and may not reveal sufficient details for complete ablation of the potential critical isthmus. Purpose We hypothesized that a novel strategy of combining ultra-high density (HD) pace-mapping using the PASO algorithm and Carto system to match the induced/clinical VT may aid in the reconstruction of the VT critical isthmus and effective VT ablation leading to reduce the risks of VT recurrence. Methods This was a prospective, multi-center trial conducted between January 2021 and July 2023. We enrolled 30 patients with ischemic heart disease and scar mediated recurrent VT clinically indicated for ablation. Following induction of clinical VT, we performed ultra-HD pace-mapping (5-10 mm distance between pacing points) of the identified ventricular substrate. Using PASO Module, a pacing correlation map (PCM) was constructed based on the percentage match to the induced VT. Using the PCM and the measured stimulation to electrogram intervals, the potential VT critical isthmus was reconstructed. Radiofrequency ablation was carried out to completely transect the delineated isthmus. Post ablation, repeat HD mapping and ablation was performed, until the PASO % correlation dropped from >93% to <70%, indicating at least uni-directional (orthodromic to the perceived VT circuit) conduction block through the ablation line. Follow-up data, including ICD interrogations were collected via chart review. Outcomes were compared to 60 propensity-score matched patients with an ICD who were enrolled in the Ranolazine in High-Risk Patients with Implanted Cardioverter-Defibrillators (RAID) trial who did not undergo VT ablation and served as the control group. The primary endpoint was the first occurrence of any VT at 1-year of follow-up. Results Patients enrolled had a mean age of 69 ± 9 years and 13% were women. Propensity matched patients from the RAID trial had similar baseline clinical characteristics to patients who underwent VT ablation (Table). At 1 year follow up, there was a significantly lower cumulative probability of VT/VF recurrent events in the patients who underwent PCM guided ablation as compared with the control group (17% vs 69%, respectively; log-rank p<0.001 Figure). There were no serious procedure related complications with all patients remaining free of adverse events or death at 30 days. Conclusion Our findings suggest that ablation for unstable or unmappable VT is enhanced by ultra-high density pace-mapping to reconstruct the potential VT circuit and is associated with a significantly lower rate of recurrent VT as compared with patients managed with aggressive and escalating medical therapy.Cumulative probability of ICD therapyBaseline clinical characteristics

Worse outcomes in patients with cardiac sarcoidosis and involvement of the right ventricle in cardiac magnetic resonance

Abstract Background Cardiac sarcoidosis (CS) can manifest with variety of unspecific symptoms. It can mimic all types of cardiomyopathies but most often it resembles dilated cardiomyopathy. Involvement of right ventricle (RV) is rare and may lead to a false diagnosis of arrhythmogenic right ventricular cardiomyopathy and delay of the immunosuppressive therapy. Purpose The aim of this research was to study the characteristics and the outcomes of this peculiar subtype of patients. Methods We analyzed 112 patients diagnosed with CS after elaborate work-up with cardiac magnetic resonance (CMR), FDG PET and endomyocardial biopsy (EMB). All patients underwent follow-up for occurrence of combined endpoint of death, LV assist device implantation or heart transplantation. Patients with evidence of late gadolinium enhancement (LGE) involving RV (RV group) were identified and compared to the rest (DCM group) for baseline clinical characteristics, arhythmic outcomes and combined endpoint. Results Involvement of the RV in CMR was observed in 19 (17%) patients. Patients in the RV group were more frequently male: 84% vs. 57%, P = 0.032. EMB confirmed CS in 63% vs. 19.4% in the DCM group; P= 0.0001. LV ejection fraction in the RV group was comparable to the DCM group: 42±14% vs. 45±14%; P = 0.3. Furthermore, in the RV group the rates of sustained ventricular tachycardia were significantly higher than the DCM: 68% vs. 34%; P = 0.009. Long-term immunosuppressive therapy was started in 74% in RV and in 70% of the DCM group; P=0.77. Despite this, during follow-up, the rate of death, LVAD implantation or heart transplantation was significantly higher in the RV than in the DCM group; 26.3% vs. 7.5%; P = 0.03. In binary logistic analysis, the OR for the combined endpoint was 4.4; 95% CI 1.2-15.7. Conclusions Patients with CS and RV involvement in CMR have worse outcomes as compared to patients presenting as DCM, despite the comparable LV EF and immunosuppressive therapy.

Current US prevalence of myocardial injury patterns and clinical outcomes among hospitalised patients with familial hypercholesterolaemia: insight from the National Inpatient Sample—a retrospective cohort study

BackgroundFamilial hypercholesterolaemia (FH) increases propensity for premature atherosclerotic disease. Knowledge of inpatient outcomes among patients with FH admitted with acute myocardial injury (AMI) is limited.ObjectivesOur study aimed to identify myocardial...

Efficacy of catheter ablation for ventricular tachycardia in ischemic cardiomyopathy patients without an ICD implantation

BackgroundThe implantable cardioverter-defibrillator (ICD) prevents sudden cardiac death in patients with ischemic cardiomyopathy (ICM). Catheter ablation has been shown to effectively reduce ventricular tachycardia (VT) recurrence, yet its efficacy in patients without an ICD implantation remains uncertain. ObjectiveWe aimed to investigate the outcomes of ablation for VT in patients with ICM without a backup ICD. MethodsPatients with ICM who received ablation for VT without an ICD implantation were included in this study. Ablation was guided by either activation mapping or substrate mapping. Endocardial ablation was the primary strategy; epicardial access was considered when endocardial ablation failed. The primary end point was VT recurrence during follow-up; secondary end points included cardiovascular rehospitalization, all-cause mortality, and a composite of these events. ResultsA total of 114 patients were included, with the mean age of 58.2 ± 11.1 years, 102 of whom (89.5%) were male. Twelve patients (10.5%) underwent endo-epicardial ablation, whereas the rest received endocardial ablation. With a median follow-up of 53.8 months (24.8–84.2 months), VT recurred in 45 patients (39.5%), and 6 patients (5.3%) died, including 2 sudden cardiac deaths. The recurrence rate of VT was significantly lower in patients undergoing endo-epicardial ablation than in those with endocardial ablation only (8.3% vs 43.1%; log-rank P = .032). After multivariate adjustment, epicardial ablation remained associated with a reduced risk of VT recurrence (hazard ratio, 0.14; 95% confidential interval, 0.02–0.98; P = .048). ConclusionPatients with ICM undergoing VT ablation without a backup ICD experienced a notably low rate of arrhythmic death. Most recurrences proved nonlethal.

Multiple ventricular fibrillation therapy triggered at slower ventricular tachycardia rate – What is the mechanism?

Multiple ventricular fibrillation therapy triggered at slower ventricular tachycardia rate – What is the mechanism?

Therapeutic potential of conduction system pacing as a method for improving cardiac output during ventricular tachycardia.

Ventricular tachycardia (VT) reduces cardiac output through high heart rates, loss of atrioventricular synchrony, and loss of ventricular synchrony. We studied the contribution of each mechanism and explored the potential therapeutic utility of His bundle pacing to improve cardiac output during VT. Study 1 aimed to improve the understanding of mechanisms of harm during VT (using pacing simulated VT). In 23 patients with left ventricular impairment, we recorded continuous ECG and beat-by-beat blood pressure measurements. We assessed the hemodynamic impact of heart rate and restoration of atrial and biventricular synchrony. Study 2 investigated novel pacing interventions during clinical VT by evaluating the hemodynamic effects of His bundle pacing at 5bpm above the VT rate in 10 patients. In Study 1, at progressively higher rates of simulated VT, systolic blood pressure declined: at rates of 125, 160, and 190bpm, -22.2%, -42.0%, and -58.7%, respectively (ANOVA p < 0.0001). Restoring atrial synchrony alone had only a modest beneficial effect on systolic blood pressure (+ 3.6% at 160bpm, p = 0.2117), restoring biventricular synchrony alone had a greater effect (+ 9.1% at 160bpm, p = 0.242), and simultaneously restoring both significantly increased systolic blood pressure (+ 31.6% at 160bpm, p = 0.0003). In Study 2, the mean rate of clinical VT was 143 ± 21bpm. His bundle pacing increased systolic blood pressure by + 14.2% (p = 0.0023). In 6 of 10 patients, VT terminated with His bundle pacing. Restoring atrial and biventricular synchrony improved hemodynamic function in simulated and clinical VT. Conduction system pacing could improve VT tolerability and treatment.

Determining the recurrence rate of premature ventricular complexes and idiopathic ventricular tachycardia after radiofrequency catheter ablation with the help of designing a machine-learning model

Ventricular arrhythmias increase cardiovascular morbidity and mortality. Recurrent PVCs and IVT are generally considered benign in the absence of structural heart abnormalities. Artificial intelligence is a rapidly growing field. In recent years, medical professionals have shown great interest in the potential use of ML, an integral part of AI, in various disciplines, including diagnostic applications, decision-making, prognostic stratification, and solving complex pathophysiological aspects of diseases from these data at extraordinary complexity, scale, and acquisition rate. The aim of this study was to design an ML model to predict the probability of PVC and IVT recurrence after RF ablation.Data of patients were collected and manipulated using traditional analysis and various artificial intelligence models, namely MLP, Gradient Boosting Machines, Random Forest, and Logistic Regression.Hypertension, male sex, and the use of non-irrigate catheters were associated with less freedom from arrhythmia. All these results were obtained through traditional analytic methods, and according to AI, none of the variables had a clear effect on the recurrence of arrhythmia.Each AI model presents unique strengths and weaknesses, and further optimization and fine-tuning of these models are necessary to increase their clinical utility. By expanding the dataset, improved predictions can be fostered to ultimately increase the clinical utility of AI in predicting PVC erosion outcomes.

Comparison of novel intrinsic versus conventional antitachycardia pacing for ventricular tachycardia among implantable cardioverter-defibrillator recipients.

Intrinsic antitachycardia pacing (iATP) is a novel automated antitachycardia pacing (ATP) that provides individual treatment to terminate ventricular tachycardia (VT). However, the clinical efficacy of iATP in comparison with conventional ATP is unknown. We aim to compare the termination rate of VT between iATP and conventional ATP in patients with implantable cardioverter-defibrillators using a unique setting of different sequential orders of both ATP algorisms. Patients with the iATP algorithm were assigned to iATP-first and conventional ATP-first groups sequentially. In the iATP-first group, a maximum of seven iATP sequences were delivered, followed by conventional burst and ramp pacing. In contrast, in the conventional ATP-first group, two bursts and ramp pacing were initially programmed, followed by iATP sequences. We compared the success rates of VT termination in the first and secondary programmed ATP zones between the two groups. Fifty-eight and 56 patients were enrolled in the iATP-first and conventional ATP-first groups, and 67 and 44 VTs were analyzed in each group, respectively. At the first single ATP therapy, success rates were 64% and 70% in the iATP and conventional groups, respectively. At the end of the first iATP treatment zone, the success rate increased from 64% to 85%. Moreover, secondary iATP therapy following the failure of conventional ATPs increased the success rate from 80% to 93%. There was a significant benefit of alternative iATP for VT termination compared to secondary conventional ATP (100% vs. 33%, p = .028). iATP may be beneficial as a secondary therapy after failure of conventional ATP to terminate VT.

Characterization of cardiac involvement in patients with LMNA splice-site mutation-related dilated cardiomyopathy and sudden cardiac death.

Introduction: LMNA splicing mutations occur in 9.1% of cases with cardiac involvement cases, but the phenotype and severity of disease they cause have not yet been systematically studied. The aim of this study was to understand the clinical and pathogenic characteristics of the LMNA splice-site mutation phenotype in patients with LMNA-related dilated cardiomyopathy (DCM) and sudden cardiac death (SCD). Methods and Results: First, we reported a novel family with LMNA-related DCM and SCD, and the clinical characteristics of all current patients with LMNA splicing mutations were further summarized through the ClinVar database. Seventeen families with a total of 134 individuals, containing a total of 15 LMNA splicing mutation sites, were enrolled. A total of 42 subjects (31.3%) had SCD. Compared without with the non-DCM group (n = 56), the patients within the DCM group (n = 78) presented a lower incidence of atrioventricular block (AVB) (p = 0.015) and a higher incidence rates of non-sustained ventricular tachycardia (p = 0.004),) and implantable cardioverter defibrillator (ICD) implantation (p = 0.005). Kaplan‒Meier survival analysis showed that the patients with pacemaker (PM) implantation had a significantly reduced the occurrence of SCD compared to patientswith those without PM implantation (log-rank p < 0.001), while there was no significant difference in ICD implantation between the two groups (log-rank p = 0.73). Second, we identified the family that we reported with a mutation in an LMNA c.513+1 G>A mutation in the reported family, and pathogenic prediction analysis showed that the mutation site was extremely harmful. Next, we conducted gene expression levels and cardiac pathological biopsy studies on the proband of this family. We found that the expression of normal LMNA mRNA from the proband was significantly downregulated in peripheral blood mononuclear cells than incompared with healthy individuals. Finally, we comprehensively summarized the pathological characteristics of LMNA-related DCM, including hypertrophy, atrophy, fibrosis, white blood cell infiltration, intercalated disc remodeling, and downregulation of desmin and connexin 43 (Cx43) expression. Discussion: Above all, Cardiaccardiac involvement in patients with LMNA splice-site mutation presented with a high rate of SCD. Implanting a pacemaker significantly reduced the SCD rate in non-DCM patients with AVB. The pathogenic characterization was not only haveinvolved suppressed the expression of the healthy LMNA allele, but was also associated with abnormal expression and distribution of desmin and Cx43.

Sex-Related Differences in Ventricular Tachyarrhythmia Events in Patients With Implantable Cardioverter-Defibrillator and Prior Ventricular Tachyarrhythmias

BackgroundData on the risk of ventricular tachycardia (VT), ventricular fibrillation (VF), and death by sex in patients with prior VT/VF are limited. ObjectivesThis study aimed to assess sex-related differences in implantable cardioverter-defibrillator (ICD)-treated VT/VF events and death in patients implanted for secondary prevention or primary prevention ICD indications who experienced VT/VF before enrollment in the RAID (Ranolazine Implantable Cardioverter-Defibrillator) trial. MethodsSex-related differences in the first and recurrent VT/VF requiring antitachycardia pacing or ICD shock and death were evaluated in 714 patients. ResultsThere were 124 women (17%) and 590 men observed during a mean follow-up of 26.81 ± 14.52 months. Compared to men, women were at a significantly lower risk of VT/VF/death (HR: 0.67; P = 0.029), VT/VF (HR: 0.68; P = 0.049), VT/VF treated with antitachycardia pacing (HR: 0.59; P = 0.019), and VT/VF treated with ICD shock (HR: 0.54; P = 0.035). The risk of recurrent VT/VF was also significantly lower in women (HR: 0.35; P < 0.001). HR for death was similar to the other endpoints (HR: 0.61; P = 0.162). In comparison to men, women presented with faster VT rates (196 ± 32 beats/min vs 177 ± 30 beats/min, respectively; P = 0.002), and faster shock-requiring VT/VF rates (258 ± 56 beats/min vs 227 ± 57 beats/min, respectively; P = 0.30). There was a significant interaction for the risk of VT/VF by race (P = 0.013) with White women having significantly lower risk than White men (HR: 0.36; P < 0.001), whereas Black women had a similar risk to Black men (HR: 1.06; P = 0.851). ConclusionsWomen with a history of prior VT/VF experienced a lower risk recurrent VT/VF requiring ICD therapy when compared to men. Black Women had a risk similar to men, whereas the lower risk for VT/VF in women was observed primarily in White women. (Ranolazine Implantable Cardioverter-Defibrillator Trial; NCT01215253)

Abstract 13943: Comparison of the Frequency and Time to True Ventricular Tachycardia Among Patients in the Cardiac, Medical/Surgical and Neurologic Intensive Care Units

Introduction: Continuous ECG monitoring is the non-invasive gold standard used to identify ventricular tachycardia (VT), yet 87% of current bedside monitor VTs could be false. Therefore, knowing the burden of true VT is essential to guide treatment to those at greatest risk of poor outcomes. Hypothesis: When stratifying by intensive care unit (ICU) (cardiac, medical/surgical, neurological), there will be differences in: 1) demographic and clinical characteristics of patients with true VT; and 2) frequency and time to first true VT. Methods: Retrospective cohort study of adults admitted to an academic medical center ICU, 9/13-4/15. Potential VTs among 5,679 consecutive ICU patients were manually annotated by clinicians as true/false. Patient-level data were extracted from the health record. We used Kaplan-Meier and Cox proportional hazards methods to calculate time to first true VT and 60-day VT rate by ICU type. Results: There were differences in all characteristics examined (p&lt;0.0001)(Table) and frequency of true VT, stratified by ICU type (log-rank p&lt;0.0001)(Figure). After adjustment for age, gender, and risk factors (Table), CICU patients had a 42% increased rate (HR 1.42, 95% CI 1.16-1.74) and NICU patients had a 28% decreased rate of VT (HR 0.72, 95% CI 0.59-0.89) compared to M/SICU patients. Conclusion: Patients in the CICU experienced true VT much earlier (1.5 days) after admission than patients in the M/SICU and NICU. In addition, CICU patients had a higher rate of true VT and associated VT risk factors as compared to M/SICU and NICU patients. As expected, known cardiac risk factors are associated with true VT, but may be hidden among false alarms during bedside monitoring.

Abstract 14684: Ambulatory Electrocardiogram for Mortality Risk Stratification in Arrhythmic Mitral Valve Prolapse

Introduction: Mitral valve prolapse (MVP) has been associated with sudden death. There is little data on whether ambulatory ECG monitoring can be used to better define risk. Hypothesis: Severity of ventricular arrhythmia (VA) on ambulatory ECG is associated with mortality in MVP patients. Methods: We studied patients aged 18 - 90 years with MVP on echocardiography between 2016-19 at our institution who underwent ambulatory ECG monitoring. Ambulatory ECGs were reviewed for PVC burden and rate of non-sustained ventricular tachycardia (NSVT). VA severity was classified as none (PVC&lt;1% and no NSVT), mild (PVC&gt;1% or NSVT&lt;120 beats per minute [bpm]), moderate (NSVT 120-179 bpm) and severe (NSVT≥180 bpm). Kaplan-Meier survival analysis was used to assess whether VA severity is associated with mortality. Results: Holter monitoring was performed in 188 (29.5%) of 637 MVP patients. None, mild, moderate and severe VA was present in 91 (48.4%), 27 (14.4%), 56 (29.8%) and 14 (7.5%), respectively. On multivariate analysis of clinical and echocardiographic features, only bileaflet prolapse was associated with moderate to severe VA (odds ratio [95% CI], 2.10 [1.05-4.16, p=0.03). After a median (IQR) follow-up of 33 (19-46) months, 8 (4.2%) died. VA severity was positively associated with mortality (p=0.0189). Conclusions: Ventricular arrhythmia is frequently present in MVP. Increased severity of ventricular arrhythmia on ambulatory monitoring portends a worse prognosis in MVP patients. Ambulatory ECG monitoring should be considered for risk stratification in MVP patients.

Vasovagal Responses to Human Monomorphic Ventricular Tachycardia: Hemodynamic Implications From Sinus Rate Analysis

BackgroundFactors determining hemodynamic stability during human ventricular tachycardia (VT) are incompletely understood. ObjectivesThe purposes of this study were to characterize sinus rate (SR) responses during monomorphic VT in association with hemodynamic stability and to prospectively assess the effects of vagolytic therapy on VT tolerance. MethodsThis is a retrospective analysis of patients undergoing scar-related VT ablation. Vasovagal responses were evaluated by analyzing sinus cycle length before VT induction and during VT. SR responses were classified into 3 groups: increasing (≥5 beats/min, sympathetic), decreasing (≥5 beats/min, vagal), and unchanged, with the latter 2 categorized as inappropriate SR. In a prospective cohort (n = 30) that exhibited a failure to increase SR, atropine was administered to improve hemodynamic tolerance to VT. ResultsIn 150 patients, 261 VT episodes were analyzed (29% untolerated, 71% tolerated) with median VT duration 1.6 minutes. A total of 52% of VT episodes were associated with a sympathetic response, 31% had unchanged SR, and 17% of VTs exhibited a vagal response. A significantly higher prevalence of inappropriate SR responses was observed during untolerated VT (sustained VT requiring cardioversion within 150 seconds) compared with tolerated VT (84% vs 34%; P < 0.001). Untolerated VT was significantly different between groups: 9% (sympathetic), 82% (vagal), and 32% (unchanged) (P < 0.001). Atropine administration improved hemodynamic tolerance to VT in 70%. ConclusionsNearly one-half of VT episodes are associated with failure to augment SR, indicative of an under-recognized pathophysiological vasovagal response to VT. Inappropriate SR responses were more predictive of hemodynamic instability than VT rate and ejection fraction. Vagolytic therapy may be a novel method to augment blood pressure during VT.

Dysrhythmia in acute coronary syndrome patients undergoing coronary artery bypass grafting surgery at hanoi heart hospital

Objectives: Many studies have demonstrated arrhythmias were common in acute coronary syndrome and coronary artery bypass grafting surgery. Although the most of these arrhythmias were transient and have a benign course, but it may represent a significant source of morbidity and mortality. This study aimed to establish the temporal change pattern of arrhythmias observed to determine the incidence and characteristics of dysrhythmia.&#x0D; Methods: A prospective method was used to study 52 consecutive patients with acute coronary syndrome who were assessed using 24-hour Holter recordings before CABG and 1 week, 3 months, and 6 months after the surgery from June 2016 to August 2018 at Hanoi Heart Hospital.&#x0D; Results: New appearance of atrial fibrillation after coronary artery bypass grafting surgery increased by time, at 7 days was 17.3%, after 3 and 6 months were 10 - 18.4%. Percentage of ventricular dysrhythmias was highest before surgery 8.67%, decreased after surgery and lowest after 6 months. The rate of short ventricular tachycardia at 7 days after surgery was highest (11.8%), followed by the preoperative period (3.8%), decreased and disappeared after 6 months. Ventricular arrhythmias with Lown (grade &gt; 3) preoperative was 44.2%, increased at 7 days postop was 51.9% and decreased postop 3 - 6 month (28 - 20%).&#x0D; Conclusion: New appearances of atrial fibrillation after coronary artery bypass grafting surgery increased by time. Dysrhythmia was acutely affected by myocardial ischemia and coronary artery bypass grafting surgery.

Monitoring for arrhythmia in transthyretin cardiac amyloidosis with remote patch devices

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Transthyretin cardiac amyloidosis (ATTR-CA) is associated with an increased incidence of arrhythmias. We hypothesized that non-invasive, two-week outpatient cardiac rhythm monitoring of patients with ATTR-CA would detect high rates of ventricular tachycardia and atrial fibrillation/flutter (AF). Purpose To characterize arrhythmia in patients with ATTR-CA on two-week, non-invasive cardiac rhythm monitors. Methods 38 patients with ATTR-CA (mean age 76.9 SD 10.0 years, 89.5% male) who underwent two-week remote external patch monitoring were included in this single center retrospective study. An age-matched control group included 38 patients (mean age 73.9 SD 12.3, 76.3% male) who underwent the same cardiac rhythm monitoring as part of neurological workups. Results NSVT was detected on the remote monitor in 81.6% of ATTR-CA patients and AF was detected in 26.3% of patients. ATTR-CA was associated with higher rates of NSVT and AF compared to the control group (28.9% with NSVT and 5.3% with AF). As seen in Figure 1, there were only three ATTR-CA patients without either AF, NSVT, advanced atrioventricular block, or a significant pause detected on remote monitor. Among the ATTR-CA group, at median 45 weeks follow-up, there were 4 heart failure hospitalizations, 2 cardiovascular events (1 episode of sustained VT and 1 stroke), 6 permanent pacemakers placed, and 3 implantable cardioverter-defibrillators placed, including one for sustained VT. NSVT and AF were not associated with a composite of these adverse outcome. Conclusion ATTR-CA was associated with high rates of NSVT and AF on noninvasive remote monitors. While evidence regarding the management of arrhythmias, particularly NSVT/VT, in ATTR-CA remains limited, two-week noninvasive cardiac monitoring can be considered to aid in risk stratification for both atrial and ventricular arrhythmias in ATTR-CA.

Hemodynamical consequences and tolerance of sustained ventricular tachycardia.

Factors underlying clinical tolerance and hemodynamic consequences of monomorphic sustained ventricular tachycardia (VT) need to be clarified. Intra-arterial pressures (IAP) during VT were collected in patients admitted for VT ablation and correlated to clinical, ECG and baseline echocardiographical parameters. 114 VTs from 58 patients were included (median 67 years old, 81% ischemic heart disease, median left ventricular ejection fraction 30%). 61 VTs were untolerated needing immediate termination (54%). VT tolerance was tightly linked to the evolution of IAPs. Faster VT rates (p<0.0001), presence of resynchronization therapy (p = 0.008), previous anterior myocardial infarction (p = 0.009) and more marginally larger baseline QRS duration (p = 0.1) were independently associated with VT tolerance. Only an inferior myocardial infarction was more often present in patients with only tolerated VTs vs patients with only untolerated VTs in multivariate analysis (OR 3.7, 95% CI 1.4-1000, p = 0.03). In patients with both well-tolerated and untolerated VTs, a higher VT rate was the only variable independently associated with untolerated VT (p = 0.02). Two different patterns of hemodynamic profiles during VT could be observed: a regular 1:1 relationship between electrical (QRS) and mechanical (IAP) events or some dissociation between both. VT with the second pattern were more often untolerated compared to the first pattern (78% vs 29%, p<0.0001). This study helps to explain the large variability in clinical tolerance during VT, which is clearly related to IAP. VT tolerance may be linked to resynchronization therapy, VT rate, baseline QRS duration and location of myocardial infarction.

Systematic Electrophysiological Study Prior to Pulmonary Valve Replacement in Tetralogy of Fallot: A Prospective Multicenter Study.

Ventricular arrhythmias and sudden death are recognized complications in tetralogy of Fallot. Electrophysiological studies (EPS) before pulmonary valve replacement (PVR), the most common reintervention in tetralogy of Fallot, could potentially inform therapy to improve arrhythmic outcomes. A prospective multicenter study was conducted to systematically assess EPS with programmed ventricular stimulation in patients with tetralogy of Fallot referred for PVR from January 2020 to December 2021. A standardized stimulation protocol was used across all centers. A total of 120 patients were enrolled, mean age 39.2±14.5 years, 53.3% males. Sustained ventricular tachycardia was induced in 27 (22.5%) patients. When identifiable, the critical isthmus most commonly implicated (ie, in 90.0%) was between the ventricular septal defect patch and pulmonary annulus. Factors independently associated with inducible ventricular tachycardia were history of atrial arrhythmia (OR, 8.56 [95% CI, 2.43-34.73]) and pulmonary annulus diameter >26 mm (OR, 5.05 [95% CI, 1.47-21.69]). The EPS led to a substantial change in management in 23 (19.2%) cases: 18 (15.0%) had catheter ablation, 3 (2.5%) surgical cryoablation during PVR, and 9 (7.5%) defibrillator implantation. Repeat EPS 5.1 (4.8-6.2) months after PVR was negative in 8 of 9 (88.9%) patients. No patient experienced a sustained ventricular arrhythmia during 13 (6.1-20.1) months of follow-up. Systematically performing programmed ventricular stimulation in patients with tetralogy of Fallot referred for PVR yields a high rate of inducible ventricular tachycardia and carries the potential to alter management. It remains to be determined whether a standardized treatment approach based on the results of EPS will translate into improved outcomes. URL: https://www. gov; Unique identifier: NCT04205461.

Abstract P539A: Advanced Chronic Kidney Disease Does Not Significantly Affect All-Cause Mortality and Rate of Hemodynamic Complications in Acute Pericarditis

Background: Advanced chronic kidney disease (advanced CKD) patients have several metabolic, immunologic, and hemodynamic derangements that can negatively impact the natural history of cardiac disease. Some efficacious treatments for acute pericarditis such as colchicine and NSAIDS may not be well tolerated by advanced CKD patients. Hypothesis: Advanced CKD may portend worse outcomes based on clinical severity and likely higher side effect of treatments among patients hospitalized with acute pericarditis. Method: A retrospective cohort study with data from the 2016 to 2018 combined National Inpatient Sample (NIS) database was employed. ICD-10 codes were used to sample all adult admissions for acute pericarditis who were dichotomized based on the presence of a secondary diagnosis of advanced CKD including CKD stage 4, stage 5 and dialysis dependent patients. Primary outcomes of study were Mortality rate, length of stay and total hospital charge. Secondary outcomes were cardiac tamponade, cardiogenic shock, pericardial window rate, supraventricular tachycardia (SVT), ventricular tachycardia (VT) and gastrointestinal (GI) bleeding rate. Multivariate linear and logistic regressions were used to adjust for confounders. Results: We identified a total of 36570 admissions for acute pericarditis and among these, 4139.99 representing 5.96% had associated advanced CKD diagnosis. These patients were averagely 5 years older (57.14 vs 52.35, adjusted difference of 4.80 years, 95%CI: 3.11 - 6.48, p-value &lt;0.001) and predominantly female (44.5% vs 39.12%, AOR 1.25, 95%CI: 1.02 - 1.52, p value: 0.029) compared to the counterpart cohort group. Details of study outcomes are summarized in table 1 below. Conclusion: Among patients hospitalized with acute pericarditis, the presence of advanced CKD as a secondary diagnosis was associated with increase length of stay and total charge but without statistical significance effect on odds of mortality and odds of relevant hemodynamic complications.

A Review of Novel and Emerging Non-Radiofrequency Ablation Modalities for Ventricular Arrhythmias: Towards an Individualized Substrate-guided Choice of Ablation Technology

Radiofrequency (RF) catheter ablation is the first-line modality for ventricular tachycardia (VT) ablation. Yet, recurrence rates of scar-related VTs are substantial, particularly in the complex and heterogenous nonischaemic cardiomyopathies. To address the still unmet need of delivering durable lesions to all functionally critical areas, including in conventionally inaccessible (e.g. deep mid-myocardial) or prohibitive areas (e.g. proximity to coronaries), a number of alternative interventional approaches have been proposed. Multiple reviews have summarized advanced RF strategies of how to target challenging VT substrates, but the spectrum for ablation modalities to treat ventricular arrhythmias is also rapidly growing beyond the well-established RF technology. Alternative energy sources and delivery modes to treat ventricular arrhythmias include ultra-low temperature cryoablation, pulsed field ablation, laser ablation, high-intensity focused ultrasound ablation and shock wave ablation. Stereotactic body radiation, chemical ablation with ethanol and autonomous nervous system modulation are further promising technologies to reduce arrhythmia burden. The wide variety of emerging approaches and techniques offers new opportunities to select tailored VT ablation strategies based on the individual substrate and VT characteristics. This review aims to present rational and evidence of emerging and cutting-edge non-RF VT ablation technologies to provide the reader with a compact update of this rapidly evolving field of cardiac electrophysiology. This will be complemented by a discussion about the specific VT substrates for which the individual technologies may prove to be most useful.