A rare case of ventricular tachycardia caused by an intramyocardial fibroma with successful surgical resection in an adult.

BACKGROUND: Cardiac fibromas are extremely rare in adults. The preferred treatment is surgical resection, but antiarrhythmic medications or heart transplantation have also been used previously. The cardiac imaging, particularly MRI, can be useful to help delineate between primary cardiac tumors, and surgical factors such as the extent/size of the fibroma, involvement of the coronary arteries or mitral apparatus and amount of residual myocardium influence whether surgical resection is feasible. CASE PRESENTATION: A 42-year-old male presented with a wide-complex tachycardia, unresponsive to amiodarone. An echocardiogram was performed which showed a possible posterior wall mass. A cardiac MRI showed a well circumscribed lateral wall intracardiac fibroma, measuring 5.2 × 5.1 × 3.8 cm with preserved function. Surgical resection was successful, and he was discharged without a defibrillator. CONCLUSIONS: Cardiac fibromas are encapsulated tumors which do not infiltrate myocardium and should be surgically resected if possible.

Electric storm triggered by short-coupled premature ventricular complexes in a young patient with non-obstructive hypertrophic cardiomyopathy.

Ventricular arrhythmias are commonly associated with hypertrophic cardiomyopathy with and without midventricular obstruction. Although the overall prognosis is relatively good with an annual mortality rate <1%, the propensity to potentially fatal ventricular arrhythmias (ventricular tachycardia) is the most feared complication. Electrical storms are a severe manifestation of ventricular arrhythmias, with poor outcomes. In this report, we present a case of a young patient with non-obstructive hypertrophic cardiomyopathy who presents after a syncopal episode and is found to have an electric storm that is refractory to medical therapy.

Substrate Characterization and Outcomes of Ventricular Tachycardia Ablation in Amyloid Cardiomyopathy: A Multicenter Study.

BACKGROUND: Sustained ventricular tachycardia (VT) in cardiac amyloidosis is uncommon, and the substrate and outcomes of catheter ablation are not defined. METHODS: We included 22 consecutive patients (mean age, 68±10 years; male sex, 91%) with cardiac amyloidosis (ATTR [transthyretin], n=16; light chain, n=6) undergoing catheter ablation for VT/ventricular fibrillation (VF) between 2013 and 2023 in a retrospective, observational, international study. The primary efficacy outcome was recurrent VT/VF during follow-up, while the primary safety end point included major procedure-related adverse events. RESULTS: The indication for ablation was drug-refractory VT in 17 patients (77%), and premature ventricular complex-initiated polymorphic VT/VF in 5 patients (23%). Catheter ablation was performed using endocardial (n=17.77%) or endo-epicardial approaches (n=5.23%). Complete endocardial electroanatomical voltage maps of the left and right ventricles were obtained in 17 (77%) and 10 (45%) patients, respectively. Each patient had evidence of low-voltage areas, most commonly involving the interventricular septum (n=16); late potentials were recorded in 16 patients (73%). A median of 1 (1-2) VT was inducible per patient; 12 of the 26 mappable VTs (46%) originated from the interventricular septum. Complete procedural success was achieved in 16 patients (73%), with 4 (18%) major procedure-related adverse events. After a median follow-up of 32 (14-42) months, sustained VT/VF recurrence was observed in 9 patients (41%); survival free from VT/VF recurrence was 56% (95% CI, 36%-86%) at 36-month follow-up, and most patients remained on antiarrhythmic drugs. A significant reduction in per patient implantable cardioverter defibrillator therapies was noted in the 6-month period after ablation (before: 6 [4-9] versus after: 0 [0-0]; P<0.001). In multivariable analysis, complete procedural success was associated with reduced risk of recurrent VT/VF (hazard ratio, 0.002; P=0.034). CONCLUSIONS: Catheter ablation can achieve control of recurrent VT/VF in more than half of patients with cardiac amyloidosis, and the reduction in VT/VF burden post-ablation may be relevant for quality of life. Septal substrate and risk of procedure-related complications challenge successful management of patients with cardiac amyloidosis and VT/VF.

Whole-Heart Histological and Electroanatomic Assessment of Postinfarction Cardiac Magnetic Resonance Imaging Scar and Conducting Channels.

BACKGROUND: Cardiac magnetic resonance imaging (CMR)-defined ventricular scar and anatomic conduction channels (CMR-CCs) offer promise in delineating ventricular tachycardia substrate. No studies have validated channels with coregistered histology, nor have they ascertained the histological characteristics of deceleration zones (DZs) within these channels. We aimed to validate CMR scar and CMR-CCs with whole-heart histology and electroanatomic mapping in a postinfarction model. METHODS: Five sheep underwent anteroseptal infarction. CMR (116±20 days post infarct) was postprocessed using ADAS-3D, varying pixel intensity thresholds (5545, 6040, 6535, and 7030). DZs were identified by electroanatomic mapping (129±12 days post infarct). Explanted hearts were sectioned and stained with Picrosirius red, and whole-heart histopathologic shells were generated. Scar topography as well as percentage fibrosis, adiposity, and remaining viable myocardium within 3 mm histological biopsies and within CMR-CCs were determined. RESULTS: Using the standard 6040 thresholding, CMR had 83.8% accuracy for identifying histological scar in the endocardium (κ, 0.666) and 61.4% in the epicardium (κ, 0.276). Thirty-seven CMR-CCs were identified by varying thresholding; 23 (62%) were unique. DZs colocalized to 19 of 23 (83%) CMR-CCs. Twenty (87%) CMR-CCs were histologically confirmed. Within-channel histological fibrosis did not differ by the presence of DZs (P=0.242). Within-channel histological adiposity was significantly higher at sites with versus without DZs (24.1% versus 8.3%; P<0.001). CONCLUSIONS: Postprocessed CMR-derived scars and channels were validated by histology and electroanatomic mapping. Regions of CMR-CCs at sites of DZs had higher adiposity but similar fibrosis than regions without DZs, suggesting that lipomatous metaplasia may contribute to arrhythmogenicity of postinfarction scar.

Ventricular arrhythmias and primary prevention of sudden cardiac death in Anderson-Fabry disease.

The Anderson-Fabry disease (AFD) is a X-linked lysosomal storage disorder due to the deficiency in the α-galactosidase A enzyme. Cardiovascular mortality is a major cause of death in patients with AFD and sudden cardiac death (SCD) is one of the main causes of death. The storage of glycosphingolipid along with ionic channel impairment, inflammation and fibrosis are involved in the arrhythmogenesis. Some risk factors have been associated with ventricular tachycardia (VT)/ventricular fibrillation (VF) and SCD. Left ventricular hypertrophy (LVH), cardiac fibrosis, non-sustained VTs seem to be the most important. Older age and male gender might be associated with higher risk of ventricular arrhythmias and SCD. Currently, the implantable cardioverter-defibrillator (ICD) is recommended in patients with AFD who have survived a cardiac arrest secondary to VT/VF or who experienced sustained VT causing syncope or hemodynamic compromise, and have a life expectancy >1 year. ICD implantation is also recommended in patients considered to be at high risk (e.g., patients with severe LVH or fibrosis). The present review sought to summarize the risk of ventricular arrythmias in AFD, the indications for ICD, focusing on pathophysiology and analyzing the role of possible predictors of arrhythmias in preventing SCD, especially as primary prevention.

Catheter ablation as first-line treatment for ventricular tachycardia in patients with structural heart disease and preserved left ventricular ejection fraction: a systematic review and meta-analysis.

In this systematic review and meta-analysis, we aim to evaluate the efficacy and safety of catheter ablation as the first-line treatment of ventricular tachycardia (VT) in patients with structural heart disease (SHD) and preserved left ventricular ejection fraction (LVEF). Patients with SHD are particularly susceptible to VT, a condition that increases the risk of sudden cardiac death (SCD). Implantable cardioverter-defibrillators (ICDs) can terminate VT and prevent SCD but do not prevent VT recurrence. The efficacy and safety of CA as a first-line treatment in SHD patients with preserved LVEF remain unclear. We searched PubMed/Medline, EMBASE, Web of Science, and Cochrane CENTRAL for studies reporting the outcomes of CA therapy in patients with VT and preserved LVEF, published up to January 19, 2023. The primary outcome was the incidence of SCD following catheter ablation as the first-line treatment of VT in patients with SHD and preserved LVEF. Secondary outcomes included all-cause mortality, VT recurrence, procedural complications, CA success rate, and ICD implantation after catheter ablation. We included seven studies in the meta-analysis, encompassing a total of 920 patients. The pooled success rate of catheter ablation was 84.6% (95% CI 67.2-93.6). Complications occurred in 6.4% (95% CI 4.0-9.9) of patients, and 13.9% (95% CI 10.1-18.8) required ICD implantation after ablation. VT recurrence was observed in 23.2% (95% CI 14.8-34.6) of patients, while the rate of sudden cardiac death (SCD) was 3.1% (95% CI 1.7-5.6). The overall prevalence of all-cause mortality in this population was 5% (95% CI 1.8-13). CA appears promising as a first-line VT treatment in patients with SHD and preserved LVEF, especially for monomorphic hemodynamically tolerated VT. However, due to the lack of direct comparisons with ICDs and anti-arrhythmic drugs, further research is needed to confirm these findings.

Natural Course of Electrocardiographic Features in Arrhythmogenic Right Ventricular Cardiomyopathy and Their Relation to Ventricular Arrhythmic Events.

BACKGROUND: Electrocardiographic abnormalities are common in arrhythmogenic right ventricular cardiomyopathy and are included in the 2010 Task Force Criteria. Their time course, however, remains uncertain. In this retrospective observational study, we aimed to assess the long-term evolution of electrocardiographic characteristics and their relation to ventricular arrhythmias. METHODS AND RESULTS: Three hundred fifty-three patients with arrhythmogenic right ventricular cardiomyopathy as per the 2010 Task Force Criteria with 6871 automatically processed 12-lead digital ECGs were included. The relationship between the electrocardiographic parameters and the risk of ventricular arrhythmias was assessed at 10 years from the first ECG. Electrocardiographic parameters were compared between the first contact ECG, the ECG at diagnosis, and the most recent ECG. Median time between the first and the latest ECG was 6 [interquartile range, 1-14] years. Reductions of QRS voltage, R- and T-wave amplitudes between the first, diagnostic, and the latest ECGs were observed across precordial and extremity leads. Mean QRS duration increased from 96 to 102 ms (P<0.001), terminal activation duration (V1) from 47 to 52 ms (P<0.001), and QTc from 419 to 432 ms (P<0.001). T-wave inversions in leads V3 to V6 and aVF at first ECG were associated with ventricular arrhythmias (adjusted hazard ratio [HRadj][V3], 2.03 [95% CI, 1.23-3.34] and HRadj[aVF], 1.87 [95% CI, 1.13-3.08]). CONCLUSIONS: Depolarization and repolarization parameters evolved over time in patients with arrhythmogenic right ventricular cardiomyopathy, supporting the progressive nature of arrhythmogenic right ventricular cardiomyopathy. Electrocardiographic abnormalities may be detected before diagnosis and might, although not fulfilling the 2010 Task Force Criteria, be markers of early disease. T-wave inversion in leads V3 or aVF before diagnosis was associated with ventricular arrhythmias during follow-up.

Sympathetic structural and electrophysiological remodeling in a rabbit model of reperfused myocardial infarction.

Chondroitin sulfate proteoglycans (CSPGs) inhibit sympathetic reinnervation in rodent hearts post-myocardial infarction (MI), causing regional hypoinnervation that is associated with supersensitivity of ß-adrenergic receptors and increased arrhythmia susceptibility. To investigate the role of CSPGs and hypoinnervation in the heart of larger mammals, we used a rabbit model of reperfused MI and tested electrophysiological responses to sympathetic nerve stimulation (SNS). Innervated hearts from MI and sham rabbits were optically mapped using voltage and Ca2+-sensitive dyes. SNS was performed with electrical stimulation of the spinal cord, and ß-adrenergic responsiveness was tested using isoproterenol. Sympathetic nerve density and CSPG expression were evaluated using immunohistochemistry. CSPGs were robustly expressed in the infarct region of all MI hearts, and the presence of CSPGs was associated with reduced sympathetic nerve density in the infarct versus remote region. Action potential duration (APD) dispersion and tendency for induction of ventricular tachycardia/fibrillation (VT/VF) were increased with SNS in MI but not sham hearts. SNS decreased APD at 80% repolarization (APD80) in MI but not sham hearts, whereas isoproterenol decreased APD80 in both groups. Isoproterenol also shortened Ca2+ transient duration at 80% repolarization in both groups but to a greater extent in MI hearts. Our data suggest that sympathetic remodeling post-MI is similar between rodents and rabbits, with CSPGs associated with sympathetic hypoinnervation. Despite a reduction in sympathetic nerve density, the infarct region of MI hearts remained responsive to both physiological SNS and isoproterenol, potentially through preserved or elevated ß-adrenergic responsiveness, which may underlie increased APD dispersion and tendency for VT/VF.NEW & NOTEWORTHY Here, we show that CSPGs are present in the infarcts of rabbit hearts with reperfused MI, where they are associated with reduced sympathetic nerve density. Despite hypoinnervation, sympathetic responsiveness is maintained or enhanced in MI rabbit hearts, which also demonstrate increased APD dispersion and tendency for arrhythmias following sympathetic modulation. Together, this study indicates that the mechanisms of sympathetic remodeling post-MI are similar between rodents and rabbits, with hypoinnervation likely associated with enhanced ß-adrenergic sensitivity.

Ventricular arrhythmias in the context of chronic kidney disease and electrolyte imbalance.

Patients with chronic kidney disease face a high risk of sudden cardiac death, particularly in more advanced stages of renal dysfunction. Ventricular arrhythmias are prevalent and contribute to the heightened cardiovascular mortality. This review aims to explore the intricate interplay of disease-specific risk factors, arrhythmic triggers, and electrolyte disorders that amplify susceptibility to ventricular arrhythmias and sudden cardiac death in this population and influence the efficacy of available treatments.

Electrocardiogram repolarization markers and ventricular arrhythmias in patients with takotsubo syndrome.

The predictive value of various ECG repolarization markers for the emergence of VA in patients with TTS was reviewed. The literature reports on QT, more recently on Tpe, and rarely on some more QT-derived metrics, revealing a contribution of these variables for the prediction of VA, complicating the acute, subacute, and follow-up clinical trajectory of patients with TTS. More recent literature reveals that Tpe and some other QT-based metrics, have outperformed the traditionally employed QT marker, although certainty about this awaits confirmation by future carefully designed and implemented studies.

Cardiac magnetic resonance for ventricular arrhythmias: a systematic review and meta-analysis.

BACKGROUND: Cardiac magnetic resonance (CMR) allows comprehensive myocardial tissue characterisation, revealing areas of myocardial inflammation or fibrosis that may predispose to ventricular arrhythmias (VAs). With this study, we aimed to estimate the prevalence of structural heart disease (SHD) and decipher the prognostic implications of CMR in selected patients presenting with significant VAs. METHODS: Electronic databases were searched for studies enrolling adult patients that underwent CMR for diagnostic or prognostic purposes in the setting of significant VAs. A random effects model meta-analysis of proportions was performed to estimate the prevalence of SHD. HRs were pooled together in order to evaluate the prognostic value of CMR. RESULTS: The prevalence of SHD was reported in 18 studies. In all-comers with significant VAs, the pooled rate of SHD post-CMR evaluation was 39% (24% in the subgroup of premature ventricular contractions and/or non-sustained ventricular tachycardia vs 63% in the subgroup of more complex VAs). A change in diagnosis after use of CMR ranged from 21% to 66% with a pooled average of 35% (29%-41%). A non-ischaemic cardiomyopathy was the most frequently identified SHD (56%), followed by ischaemic heart disease (21%) and hypertrophic cardiomyopathy (5%). After pooling together data from six studies, we found that the presence of late gadolinium enhancement was associated with increased risk of major adverse outcomes in patients with significant VAs (pooled HR: 1.79; 95% CI 1.33 to 2.42). CONCLUSION: CMR is a valuable tool in the diagnostic and prognostic evaluation of patients with VAs. CMR should be considered early after initial evaluation in the diagnostic algorithm for VAs of unclear aetiology as this strategy may also define prognosis and improve risk stratification.

An Unusual Case of Takotsubo Cardiomyopathy with Cardiac Arrest: The Importance of Clinical Context in Implanted Cardioverter Defibrillator Candidacy.

Takotsubo syndrome (TTS), also known as stress-induced cardiomyopathy, is characterized by acute heart failure, reversible left ventricular dysfunction, and other complications such as life-threatening arrhythmias. The management of TTS is challenging due to its unpredictable clinical course and the lack of evidence-based treatment recommendations. In this case report, we present a 71-year-old female who developed TTS with ventricular tachycardia (VT) cardiac arrest following septic shock and an exploratory laparotomy for appendicitis. Despite the presence of VT cardiac arrest and a left ventricular ejection fraction of 30-35%, an implanted cardioverter-defibrillator (ICD) was not indicated due to the rapid and satisfactory recovery of the patient's ventricular function. This case highlights the importance of considering the clinical context and the transient nature of TTS in the decision-making process for ICD candidacy.

Mechanical and electrical uncoupling: the role of cardiac magnetic resonance imaging in arrhythmogenic cardiomyopathy. Proof of concept.

OBJECTIVES: Arrhythmogenic cardiomyopathy (ACM) is a complex cardiac disorder associated with ventricular arrhythmias. Understanding the relationship between mechanical uncoupling and cardiac structural changes in ACM patients is crucial for improved risk stratification and management. METHODS: In this study, we enrolled 25 ACM patients (median age 34 years, 72% men) based on the 2019 Modified Task Force and Padua criteria. Patients were categorized by the presence or absence of clinically relevant ventricular tachycardia (crVT), necessitating emergency interventions. Right ventricular-arterial coupling (VAC) was assessed using echocardiography. Low-rank regression splines were employed to model left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) in relation to VAC. RESULTS: Positive associations were observed between VAC and LVEF (ρ = 0.472, p = 0.023), RVEF (ρ = 0.522, p = 0.038), and right ventricular (RV) indexed stroke volume (ρ = 0.79, p < 0.001). Patients with crVT exhibited correlations with RV shortening, reduced RVEF (39.6 vs. 32.2%, p = 0.025), increased left ventricular (LV) mass (38.99 vs. 45.55, p = 0.045), and LV end-diastolic volume (LVEDV) (56.99 vs. 68.15 mL/m2, p = 0.045). Positive associations for VAC were noted with LVEDV (p = 0.039) and LV mass (p = 0.039), while negative correlations were observed with RVEF by CMR (p = 0.023) and RV shortening by echocardiography (p = 0.026). CONCLUSIONS: Our findings underscore the significance of right VAC in ACM, demonstrating correlations with RV and LVEF, RV stroke volume, and clinically relevant arrhythmias. Insights into RVEF, LV mass, and end-diastolic volume provide valuable contributions to the understanding of ACM pathophysiology and may inform risk assessment strategies.

OBJETIVOS: La miocardiopatía arritmogénica (MCA) es un trastorno cardíaco complejo asociado con arritmias ventriculares (AV). Comprender la relación entre el desacoplamiento mecánico y los cambios estructurales cardíacos en pacientes con MCA es crucial para una estratificación de riesgos y una gestión mejorada. MÉTODOS: En este estudio, reclutamos a 25 pacientes con MCA (edad media 34 años, 72% hombres) basándonos en los criterios del Task Force 2019 y los criterios de Padua. Los pacientes se clasificaron según la presencia o ausencia de taquicardia ventricular clínicamente relevante (crVT), que requería intervenciones de emergencia. Se evaluó el acoplamiento ventricular derecho-arterial (VAC) mediante ecocardiografía. Se utilizaron low-rank regression splines para modelar la fracción de eyección del ventrículo izquierdo (FEVI) y la fracción de eyección del ventrículo derecho (FEVD) en relación con el VAC. RESULTADOS: Se observaron asociaciones positivas entre el VAC y la FEVI (ρ = 0.472, p = 0.023), la FEVD (ρ = 0.522, p = 0.038) y el volumen de eyección indexado del ventrículo derecho (ρ = 0.79, p < 0.001). Los pacientes con crVT mostraron correlaciones con acortamiento del ventrículo derecho, disminución de la FEVD (39.6 vs. 32.2%, p = 0.025), aumento de la masa ventricular izquierda (38.99 vs. 45.55, p = 0.045) y volumen diastólico final del ventrículo izquierdo (VDVI) (56.99 vs. 68.15 mL/m2, p = 0.045). Se observaron asociaciones positivas para el VAC con el VDVI (p = 0.039) y la masa ventricular izquierda (p = 0.039), mientras que se observaron correlaciones negativas con la FEVD por RMC (p = 0.023) y el acortamiento del ventrículo derecho por ecocardiografía (p = 0.026). CONCLUSIONES: Nuestros hallazgos subrayan la importancia del VAC derecho en la MCA, demostrando correlaciones con la FEVD y FEVI, el volumen de eyección del ventrículo derecho y arritmias clínicamente relevantes. Las percepciones sobre la FEVD, la masa ventricular izquierda y el volumen diastólico final proporcionan contribuciones valiosas para comprender la fisiopatología de la MCA y pueden informar estrategias de evaluación de riesgos.

Acute post-procedural inducibility is a poor predictor of clinical outcomes in high-risk patients (PAINESD > 17) undergoing scar-related ventricular tachycardia ablation.

AIMS: Ventricular tachycardia (VT) non-inducibility in response to programmed ventricular stimulation (PVS) is a widely used procedural endpoint for VT ablation despite inconclusive evidence with respect to clinical outcomes in high-risk patients. The aim is to determine the utility of acute post-ablation VT inducibility as a predictor of VT recurrence, mortality, or mortality equivalent in high-risk patients. METHODS AND RESULTS: We conducted a retrospective analysis of high-risk patients (defined as PAINESD > 17) who underwent scar-related VT ablation at our institution between July 2010 and July 2022. Patients' response to PVS (post-procedure) was categorized into three groups: Group A, no clinical VT or VT with cycle length > 240 ms inducible; Group B, only non-clinical VT with cycle length > 240 ms induced; and Group C, all other outcomes (including cases where no PVS was performed). The combined primary endpoint included death, durable left ventricular assist device placement, and cardiac transplant (Cox analysis). Ventricular tachycardia recurrence was considered a secondary endpoint (competing risk analysis). Of the 1677 VT ablation cases, 123 cases met the inclusion criteria for analysis. During a 19-month median follow-up time (interquartile range 4-43 months), 82 (66.7%) patients experienced the composite primary endpoint. There was no difference between Groups A and C with respect to the primary [hazard ratio (HR) = 1.21 (0.94-1.57), P = 0.145] or secondary [HR = 1.18 (0.91-1.54), P = 0.210] outcomes. These findings persisted after multivariate adjustments. The size of Group B (n = 13) did not permit meaningful statistical analysis. CONCLUSION: The results of post-ablation PVS do not significantly correlate with long-term outcomes in high-risk (PAINESD > 17) VT ablation patients.

Peripartum ventricular tachycardia and PVC-induced cardiomyopathy: delivering optimal care when it's time to deliver.

Ventricular tachycardia (VT) is a rare but potentially fatal complication in pregnancy. We present a case of a pregnant woman with cardiomyopathy due to frequent premature ventricular complexes (PVCs) and VT originating from the left ventricular outflow tract. After presenting late in the third trimester, the decision was made to deliver the fetus after 4 days of medication titration due to continued sustained episodes of VT. After delivery, the patient continued to have frequent PVCs and VT several months after discharge, and she ultimately underwent a PVC ablation with dramatic reduction in PVC burden and improvement in cardiomyopathy. Multidisciplinary planning with a pregnancy heart team led to appropriate contingency planning and a successful delivery. This case highlights how multidisciplinary management is best practice in pregnancy complicated by VT and the need for better diagnostic guidelines for PVC-induced cardiomyopathy in the setting of pregnancy.

Sudden cardiac arrest occurring in temporal proximity to consumption of energy drinks.

BACKGROUND: Energy drinks potentially can trigger life-threatening cardiac arrhythmias. It has been postulated that the highly stimulating and unregulated ingredients alter heart rate, blood pressure, cardiac contractility, and cardiac repolarization in a potentially proarrhythmic manner. OBJECTIVE: The purpose of this study was to describe our experience regarding sudden cardiac arrest (SCA) occurring in proximity to energy drink consumption in patients with underlying genetic heart diseases. METHODS: The electronic medical records of all SCA survivors with proven arrhythmias referred to the Mayo Clinic Windland Smith Rice Genetic Heart Rhythm Clinic for evaluation were reviewed to identify those who consumed an energy drink before their event. Patient demographics, clinical characteristics, documented energy drink consumption, and temporal relationship of energy drink consumption to SCA were obtained. RESULTS: Among 144 SCA survivors, 7 (5%; 6 female; mean age at SCA 29 ± 8 years) experienced an unexplained SCA associated temporally with energy drink consumption. Of these individuals, 2 had long QT syndrome and 2 had catecholaminergic polymorphic ventricular tachycardia; the remaining 3 were diagnosed with idiopathic ventricular fibrillation. Three patients (43%) consumed energy drinks regularly. Six patients (86%) required a rescue shock, and 1 (14%) was resuscitated manually. All SCA survivors have quit consuming energy drinks and have been event-free since. CONCLUSION: Overall, 5% of SCA survivors experienced SCA in proximity to consuming an energy drink. Although larger cohort studies are needed to elucidate the incidence/prevalence and quantify its precise risk, it seems prudent to sound an early warning on this potential risk.

Long-Term Freedom From Ventricular Arrhythmias in ARVC With Endocardial Only Ablation: Predictors of Success.

BACKGROUND: Although the epicardial predominance of substrate abnormalities has been well demonstrated in early stages of arrhythmogenic right ventricular cardiomyopathy (ARVC), endocardial (ENDO) ablation may suffice to eliminate ventricular tachycardia (VT) in some patients. OBJECTIVES: This study aimed to report the long-term outcomes of ENDO-only ablation in ARVC patients and factors that predict VT-free survival. METHODS: We included consecutive patients with Task Force Criteria diagnosis of ARVC undergoing a first ENDO-only VT ablation between 1998 and 2020. Ablation was predominantly guided by activation/entrainment mapping for mappable VTs and pace mapping/targeting abnormal electrograms for unmappable VTs. The primary endpoint was freedom from any recurrent sustained VT after the last ENDO-only ablation. RESULTS: Seventy-four ARVC patients underwent ENDO-only VT ablation. VT noninducibility was achieved in 49 (66%) patients. During median follow-up of 6.6 years (Q1-Q3: 3.4-11.2 years), 40 (54.1%) patients remained free from any VT recurrence with rare VT ≤2 episodes in additional 12.2%. Among patients with noninducibility, VT-free survival was 75.5% during long-term follow-up. In multivariable analysis, >45 y of age at diagnosis (HR: 0.41; 95% CI: 0.17-0.98) and VT noninducibility (HR: 0.36; 95% CI: 0.16-0.80) were predictors of VT-free survival. CONCLUSIONS: Long-term VT-free survival can be achieved in over half of ARVC patients following ENDO-only VT ablation, increasing to over 75% if VT noninducibility is achieved. Our results support consideration of a stepwise ENDO-only approach before proceeding to epicardial ablation if VT noninducibility can be achieved particularly in older patients.

Ventricular tachycardia due to left ventricular metastasis: A case report.

We present the case of a 60-year-old male patient who was admitted to our hospital after experiencing a syncopal episode. First ECGs showed sinus rhythm with polymorphic premature ventricular complexes and later ventricular tachycardia with a left bundle branch block morphology were recorded. Imaging with TEE and MRI revealed a space-occupying lesion in the left ventricle, which was ultimately identified as a rare cardiac metastasis of renal cell carcinoma. Treatment was initiated with monoclonal antibodies resulting in lesion regression. This case highlights the importance of comprehensive diagnostic in patients with history of malignancy.