Autopsy of all young sudden death cases is important to increase survival in family members left behind.

Sudden cardiac death (SCD) is an important public health problem worldwide, accounting for an estimated 6 to 20% of total mortality. A significant proportion of SCD is caused by inherited heart disease, especially among the young. An autopsy is crucial to establish a diagnosis of inherited heart disease, allowing for subsequent identification of family members who require cardiac evaluation. Autopsy of cases of unexplained sudden death in the young is recommended by both the European Society of Cardiology and the American Heart Association. Overall autopsy rates, however, have been declining in many countries across the globe and there is a lack of skilled trained pathologists able to carry out full autopsies. Recent studies show that not all cases of sudden death in the young are autopsied, likely due to financial, administrative, and organizational limitations as well as awareness among police, legal authorities, and physicians. Consequently, diagnoses of inherited heart disease are likely missed, along with the opportunity for treatment and prevention among surviving relatives. This article reviews the evidence for the role of autopsy in sudden death, how the cardiologist should interpret the autopsy-record and how this can be integrated and implemented in clinical practice. Finally, we identify areas for future research along with potential for healthcare reform aimed at increasing autopsy awareness and ultimately reducing mortality from SCD.

Mitral Annular Disjunction in the Context of Mitral Valve Prolapse: Identifying the At-Risk Patient.

Mitral annular disjunction (MAD), a separation between the left atrium/mitral valve annulus and the left ventricular myocardium, is frequently seen in patients with arrhythmic mitral valve prolapse. Although an association exists between MAD and ventricular arrhythmias, little is known regarding the identification of individuals at high risk. Multimodality imaging including echocardiography, computed tomography, cardiac magnetic resonance, and positron emission tomography can play an important role in both the diagnosis and risk stratification of MAD. Due to a paucity of data, clinical decision making in a patient with MAD is challenging and remains largely empirical. Although MAD itself can be corrected surgically, the prevention and treatment of associated arrhythmias may require medical therapy, catheter ablation, and an implantable cardioverter-defibrillator. Prospective data are required to define the role of implantable cardioverter-defibrillators, targeted catheter ablation, and surgical correction in selected, at-risk patients.

Long-term efficacy and safety of tailored immunosuppressive therapy in immune-mediated biopsy-proven myocarditis: A propensity-weighted study.

AIMS: Standardized immunosuppressive therapy (IS) had been previously investigated in biopsy-proven (BP) lymphocytic myocarditis with heart failure (HF). This study evaluated efficacy and safety of tailored IS in BP immune-mediated myocarditis, irrespective of histology and clinical presentation. METHODS AND RESULTS: Consecutive BP myocarditis patients treated with long-term tailored IS on top of optimal medical therapy (OMT), were compared with OMT non-IS controls using propensity-score weighting. The primary outcome was a composite of death or heart transplant, the secondary outcome was a composite of biventricular function, New York Heart Association (NYHA) class variation, and relapse. IS was managed by a multidisciplinary Cardioimmunology Team, involved a safety checklist and active patients' education. Ninety-one IS patients were compared with 267 non-IS patients. IS patients more frequently had systemic immune-mediated diseases (35% vs. 9.7%), lower baseline echocardiographic left ventricular ejection fraction (35% vs. 43%), lower right ventricular fractional area change (34% vs. 41%) and higher frequency of active lymphocytic, eosinophilic and giant cell myocarditis (71% vs. 58%, 12% vs. 1.1%, and 6.6% vs. 1.5%, respectively). At 5-year follow up, no difference was observed in the primary outcome (survival rate 93% in IS vs. 87% in non-IS), but IS patients had a higher relapse rate. Thus, IS patients, with a lower biventricular function and a higher risk profile at baseline, presented similar biventricular function and NYHA class to non-IS patients at follow-up. Minor adverse drug reactions occurred in 13% of patients, all resolved with therapy switch. CONCLUSIONS: Prolonged tailored IS is effective and safe in BP immune-mediated myocarditis irrespective of histology and clinical presentation.

CMR Predictors of Favorable Outcome in Myocarditis: A Single-Center Experience.

Background: Cardiovascular magnetic resonance (CMR) has emerged as the most accurate, non-invasive method to support the diagnosis of clinically suspected myocarditis and as a risk-stratification tool in patients with cardiomyopathies. We aim to assess the diagnostic and prognostic role of CMR at diagnosis in patients with myocarditis. Methods: We enrolled consecutive single-center patients with 2013 ESC consensus-based endomyocardial biopsy (EMB)-proven or clinically suspected myocarditis undergoing CMR at diagnosis. The pre-specified outcome was defined as NYHA class > I and echocardiographic left ventricular ejection fraction (LVEF) < 50% at follow-up. Results: We included 207 patients (74% male, median age 36 years; 25% EMB-proven). CMR showed the highest sensitivity in myocarditis with infarct-like presentation. Patients with EMB-proven myocarditis were more likely to have diffuse LGE and right ventricular LGE (p < 0.001), which was also more common among patients with arrhythmic presentation (p = 0.001). The outcome was met in 17 patients at any follow-up time point, more commonly in those with larger biventricular volumes (p < 0.001), CMR-based diagnosis of dilated cardiomyopathy (p < 0.001), and ischemic LGE (p = 0.005). Higher biventricular systolic function (p < 0.001) and greater LGE extent (p = 0.033) at diagnosis had a protective effect. Conclusions: In our single-center cohort of rigorously defined myocarditis patients, higher biventricular systolic function and greater LGE extent on CMR at diagnosis identified patients with better functional class and higher left ventricular ejection fraction at follow-up. Conversely, larger biventricular volumes, CMR-based DCM features, and the presence of an ischemic LGE pattern at diagnosis were predictors of worse functional class and LV systolic dysfunction at follow-up. Larger prospective studies are warranted to extend our findings to multi-center cohorts.

Radioiodine whole body scan pitfalls in differentiated thyroid cancer.

PURPOSE: whole body scan (WBS) performed following diagnostic or therapeutic administration of I-131 is useful in patients with differentiated thyroid carcinoma. However, it can be falsely positive in various circumstances. We aimed to report a series of pitfalls in a clinical perspective. METHODS: A search in the database PubMed utilizing the following terms: "false radioiodine uptake" and "false positive iodine 131 scan" has been made in January 2023. Among the 346 studies screened, 230 were included in this review, with a total of 370 cases collected. Physiological uptakes were excluded. For each patient, sex, age, dose of I-131 administered, region and specific organ of uptake and cause of false uptake were evaluated. RESULTS: 370 cases of false radioiodine uptake were reported, 19.1% in the head-neck region, 34.2% in the chest, 14.8% in the abdomen, 20.8% in the pelvis, and 11.1% in the soft tissues and skeletal system. The origin of false radioiodine uptake was referred to non-tumoral diseases in 205/370 cases (55.1%), benign tumors in 108/370 cases (29.5%), malignant tumors in 25/370 cases (6.7%), and other causes in 32/370 cases (8.7%). CONCLUSIONS: WBS is useful in the follow-up of patients with differentiated thyroid carcinoma, however it can be falsely positive in various circumstances. For this reason, it is critically important to correlate the scintigraphic result with patient's medical history, serum thyroglobulin levels, additional imaging studies and cytologic and/or histologic result.

Phenotypic Expression and Clinical Outcomes in Patients With Arrhythmogenic Cardiomyopathies.

BACKGROUND: In recent years, it has become evident that arrhythmogenic cardiomyopathy (ACM) displays a wide spectrum of ventricular involvement. Furthermore, the influence of various clinical phenotypes on the prognosis of the disease is currently being assessed. OBJECTIVES: The purpose of this study was to evaluate the impact of phenotypic expression in ACM on patient outcomes. METHODS: We conducted an analysis of 446 patients diagnosed with ACM. These patients were categorized into 3 groups based on their phenotype: arrhythmogenic right ventricular cardiomyopathy (ARVC) (right-dominant ACM), arrhythmogenic left ventricular cardiomyopathy (ALVC) (left-dominant ACM), and biventricular arrhythmogenic cardiomyopathy (BIV). We compared clinical, instrumental, and genetic findings among these groups and also evaluated their outcomes RESULTS: Overall, 44% of patients were diagnosed with ARVC, 23% with ALVC, and 33% with BIV forms. Subjects showing with ARVC and BIV phenotype had a significantly higher incidence of life-threatening ventricular arrhythmias compared with ALVC (P < 0.001). On the other hand, heart failure, heart transplantation, and death caused by cardiac causes were more frequent in individuals with BIV forms compared to those with ALVC and ARVC (P < 0.001). Finally, patients with an ALVC phenotype had a higher incidence of hot phases compared with those with ARVC and BIV forms (P = 0.013). CONCLUSIONS: The comparison of ACM phenotypes demonstrated that patients with right ventricular involvement, such as ARVC and BIV forms, exhibit a higher incidence of life-threatening ventricular arrhythmias. Conversely, ACM forms characterized by left ventricular involvement, such as ALVC and BIV, show a higher incidence of heart failure, heart transplantation, and hot phases.

Causes of sudden cardiac arrest and death and the diagnostic yield of sport preparticipation screening in children.

OBJECTIVE: Evidence on the increased risk of sports-related sudden cardiac arrest and death (SCA/D) and the potential benefit of cardiovascular preparticipation screening (PPS) in children is limited. We assessed the burden and circumstances of SCA/D and the diagnostic yield of cardiovascular PPS in children aged 8-15 years. METHODS: Data on the incidence and causes of SCA/D from 2011 to 2020 were obtained from the Veneto region (Italy) sudden death registry, hospital records and local press. During the same period, we assessed the results of annual PPS in 25 251 young competitive athletes aged 8-15 years who underwent 58 185 evaluations (mean 2.3/athlete) in Padua, Italy. RESULTS: Over 10 years, 26 SCA/D occurred in children aged 8-15 years in the Veneto region: 6 in athletes (incidence 0.7/100 000/year, all ≥12 years) versus 20 in non-athletes (0.7/100 000/year, 17/20 ≥12 years). In total, 4/6 athletes versus 1/20 non-athletes survived. The cause of SCA/D remained unexplained in four athletes and in nine non-athletes. No athlete suffered SCA/D from structural diseases potentially identifiable by PPS. The incidence of SCA/D in athletes and non-athletes was 0.2/100 000/year in the 8-11 years group versus 1.3/100 000/year in the 12-15 years group. PPS identified 26 new diagnoses of cardiovascular diseases (CVDs) at risk of SCA/D, more often in children ≥12 years old (0.06%/evaluation) than <12 years old (0.02%/evaluation, p=0.02). Among athletes with a negative PPS, two suffered unexplained SCA/D during follow-up, one during exercise. CONCLUSIONS: In children aged 8-15 years, the incidence of SCA/D and the yield of PPS for identifying at-risk CVD were both substantially higher in those ≥12 years, suggesting that systematic PPS may be more useful beyond this age.

Bicuspid aortic valve: The most frequent and not so benign congenital heart disease.

Bicuspid aortic valve (BAV) is the most frequent congenital heart disease, with an incidence of approximately 1%. It can be silent and associated with normal valve function. However, a series of complications, even catastrophic, may occur with time: valve incompetence, valve stenosis by dystrophic calcification, infective endocarditis, progressive dilatation of the ascending aorta, aortic dissection, sudden death. The problem of BAV is not just about the number of semilunar cusps, but also the aortic wall. Severe noninflammatory degenerative changes (elastic fiber fragmentation, smooth muscle cells death, mucoid extracellular matrix accumulation=MEMA) are observed in the aortic wall of BAV patients, with intrinsic weakness accounting for progressive aneurysmal dilatation of the ascending aorta, valve incompetence, and wall dissection. The link between valve and aortic wall pathology finds most probably an explanation in the embryology of the arterial pole since neurocrestal cells play a role in the development of both the ascending aorta, aortic arch, and semilunar valves. The frequent association of adult aortic coarctation and BAV provides evidence for this hypothesis. BAV has a significant genetic component as to require screening of first-degree relatives, as outlined by AHA/ACC 2022 guidelines.

Commotio cordis: Another cardiac arrest "sine materia". The 1707 early report and interpretation by G.M. Lancisi.

Sudden death by commotio cordis is rare. It is the consequence of a blunt trauma of the chest overlying the heart. The mechanism is a cardiac arrest by ventricular fibrillation in the absence of grossly or microscopically apparent myocardial injury. It has been reproduced in animals. The first historical case was reported by Giovanni Maria Lancisi in his book "De Subitaneis Mortibus'' published in 1707. Sudden death occurred in a man receiving a powerful blow under the xiphoid cartilage. Lancisi advanced the hypothesis of acute heart failure by a diastolic stand still ("death in diastole'').

Characteristics and Clinical Value of Electroanatomic Voltage Mapping in Cardiac Amyloidosis.

BACKGROUND: Cardiac amyloidoses (CAs) are an increasingly recognised group of infiltrative cardiomyopathies associated with high risk of adverse cardiac events. We sought to characterise the characteristics and clinical value of right ventricular (RV) electroanatomic voltage mapping (EVM) in CA. METHODS: Fifteen consecutive patients undergoing endomyocardial biopsy (EMB) for suspected CA (median age 75 years, 1st-3rd quartiles 64-78 years], 67% male) were enrolled in an observational prospective study. Each patient underwent RV high-density EVM using a multipolar catheter and EMB. The primary outcome was death or heart failure hospitalisation at 1-year follow-up. We recorded electrographic features at EMB sampling sites and electroanatomic data in the overall RV, and explored their correlations with histopathologic findings and primary outcomes events. RESULTS: A final EMB-proven diagnosis of immunoglobulin light chain or transthyretin CA was formulated in 6 and 9 patients, respectively. Electrogram amplitudes in the bipolar and unipolar configurations averaged 1.55 ± 0.44 mV and 5.14 ± 1.50 mV, respectively, in the overall RV, with lower values in AL CA patients. We found a significant inverse correlation between both bipolar and unipolar electrogram amplitude and amyloid burden according to EMB (P = 0.001 and P = 0.025, respectively). At 1-year follow-up, 7 patients (47%) experienced a primary outcome event; the extent of bipolar dense scar area at RV EVM was an independent predictor of primary outcome events at multivariable analysis (odds ratio 2.40; P = 0.037). CONCLUSIONS: In CA, electrogram amplitudes are around the lower limit of normal yet disproportionately low compared with the increased wall thickness. Out data suggest that RV electrogram amplitude may be a quantitative marker of amyloid burden, and that RV EVM may have prognostic value.

Proposed diagnostic criteria for arrhythmogenic cardiomyopathy: European Task Force consensus report.

Arrhythmogenic cardiomyopathy (ACM) is a heart muscle disease characterized by prominent "non-ischemic" myocardial scarring predisposing to ventricular electrical instability. Diagnostic criteria for the original phenotype, arrhythmogenic right ventricular cardiomyopathy (ARVC), were first proposed in 1994 and revised in 2010 by an international Task Force (TF). A 2019 International Expert report appraised these previous criteria, finding good accuracy for diagnosis of ARVC but a lack of sensitivity for identification of the expanding phenotypic disease spectrum, which includes left-sided variants, i.e., biventricular (ABVC) and arrhythmogenic left ventricular cardiomyopathy (ALVC). The ARVC phenotype together with these left-sided variants are now more appropriately named ACM. The lack of diagnostic criteria for the left ventricular (LV) phenotype has resulted in clinical under-recognition of ACM patients over the 4 decades since the disease discovery. In 2020, the "Padua criteria" were proposed for both right- and left-sided ACM phenotypes. The presently proposed criteria represent a refinement of the 2020 Padua criteria and have been developed by an expert European TF to improve the diagnosis of ACM with upgraded and internationally recognized criteria. The growing recognition of the diagnostic role of CMR has led to the incorporation of myocardial tissue characterization findings for detection of myocardial scar using the late­gadolinium enhancement (LGE) technique to more fully characterize right, biventricular and left disease variants, whether genetic or acquired (phenocopies), and to exclude other "non-scarring" myocardial disease. The "ring-like' pattern of myocardial LGE/scar is now a recognized diagnostic hallmark of ALVC. Additional diagnostic criteria regarding LV depolarization and repolarization ECG abnormalities and ventricular arrhythmias of LV origin are also provided. These proposed upgrading of diagnostic criteria represents a working framework to improve management of ACM patients.

A cardiac intimal sarcoma mimicking infective endocarditis.

Primary malignant cardiac tumors are rare and usually misdiagnosed because they can mimic more common intracardiac lesions, therefore, in clinical practice it is important to always consider even uncommon diseases in order to avoid delayed diagnosis and to plan the most appropriate therapeutic strategy in a timely fashion. We report a case of a 73-year-old man with clinical signs and imaging findings (echocardiography) suggesting infective bacterial endocarditis of the mitral valve. However, intraoperative evaluation raised suspicion that the mitral lesions had a different nature. Surgical removal of the mass was performed, and the final correct diagnosis was made through pathologic examination, revealing a mitral valve sarcoma thus allowing for the beginning of specific oncological treatment.

Left ventricular fibrosis in arrhythmic mitral valve prolapse: quantification and comparison of semi-automated techniques assessed by cardiac magnetic resonance.

PURPOSE: Left ventricular (LV) fibrosis has a key role in arrhythmogenesis in patients with mitral valve prolapse (MVP). Cardiac magnetic resonance identifies LV fibrosis by using late gadolinium enhancement (LGE) technique. LGE assessment and quantification in patients with MVP lacks of standardization protocols. METHODS: 66 MVP patients with normal systolic function and without significant regurgitation were enrolled. Semi-automated gray-scale thresholding techniques using full width at half maximum (FWHM) and 2, 3 and 5 standard deviation (SD) above the remote myocardium were used and compared with the visual assessment, considered as the gold standard. RESULTS: LGE was identified in 41 MVP patients (62%) and quantified. The mean quantity of LGE visually assessed was 2.40 ± 1.07% or 1.40 ± 0.82 g. With FWHM, LGE resulted 3.56 ± 1.23% or 1.99 ± 1.13 g. Using thresholding, the mean LGE quantity was 9.2 ± 3.1% or 4.82 ± 2.28 g for 2-SD, 5.72 ± 1.75% or 3.06 ± 1.47 g for 3-SD and 2.36 ± 0.99% or 1.29 ± 0.79 g for 5-SD. The 5-SD measurement in percentage demonstrated a good correlation with LGE quantification visually assessed (2.40 ± 1.07 vs. 2.363 ± 0.9909, p = 0.543). When compared with the gold standard, the 5-SD threshold quantification, both in percentage and in grams, revealed the least intra-observer (respectively, ICC: 0.976 and 0.966) and inter-observer variability (respectively ICC: 0.948 and 0.935). CONCLUSION: The 5-SD gray-scale threshold technique in percentage revealed the best correlation with the visual assessment and an optimal reproducibility in MVP patient.

A novel DSP zebrafish model reveals training- and drug-induced modulation of arrhythmogenic cardiomyopathy phenotypes.

Arrhythmogenic cardiomyopathy (AC) is an inherited disorder characterized by progressive loss of the ventricular myocardium causing life-threatening ventricular arrhythmias, syncope and sudden cardiac death in young and athletes. About 40% of AC cases carry one or more mutations in genes encoding for desmosomal proteins, including Desmoplakin (Dsp). We present here the first stable Dsp knock-out (KO) zebrafish line able to model cardiac alterations and cell signalling dysregulation, characteristic of the AC disease, on which environmental factors and candidate drugs can be tested. Our stable Dsp knock-out (KO) zebrafish line was characterized by cardiac alterations, oedema and bradycardia at larval stages. Histological analysis of mutated adult hearts showed reduced contractile structures and abnormal shape of the ventricle, with thinning of the myocardial layer, vessels dilation and presence of adipocytes within the myocardium. Moreover, TEM analysis revealed "pale", disorganized and delocalized desmosomes. Intensive physical training protocol caused a global worsening of the cardiac phenotype, accelerating the progression of the disease. Of note, we detected a decrease of Wnt/ß-catenin signalling, recently associated with AC pathogenesis, as well as Hippo/YAP-TAZ and TGF-ß pathway dysregulation. Pharmacological treatment of mutated larvae with SB216763, a Wnt/ß-catenin agonist, rescued pathway expression and cardiac abnormalities, stabilizing the heart rhythm. Overall, our Dsp KO zebrafish line recapitulates many AC features observed in human patients, pointing at zebrafish as a suitable system for in vivo analysis of environmental modulators, such as the physical exercise, and the screening of pathway-targeted drugs, especially related to the Wnt/ß-catenin signalling cascade.

Uneventful COVID-19 Infection and Vaccination in a Cohort of Patients with Prior Myocarditis.

Myocarditis has in rare cases been associated with COVID-19 infection and has emerged as a possible rare side effect of vaccination with anti-COVID-19 messenger RNA vaccines. However, little is known about possible COVID-19 infection- and/or vaccination-related myocarditis relapse in patients with previous clinically suspected or biopsy-proven myocarditis. Myocarditis may relapse, particularly in females with immune-mediated/autoimmune features and a predisposing immunogenetic background. We aimed to assess the prevalence of myocarditis relapse during the COVID-19 outbreak and following COVID-19 vaccination in a cohort of patients with prior myocarditis. We included in the analysis myocarditis patients on active follow-up, for whom COVID-19 infection and vaccination statuses were known, and collected data on clinical, laboratory and echocardiographic findings, and myocarditis relapse. We enrolled 409 patients, of whom 114 (28%) reported COVID-19 infection and 347 (85%) completed the vaccination scheme. Only one patient, having COVID-19 infection before the vaccination campaign started, was admitted to hospital because of pneumonia; the remaining patients had an uneventful COVID-19 infection course, with only mild symptoms. No myocarditis relapse was recorded following COVID-19 infection or vaccination. Moreover, the frequency of new myocarditis cases following the COVID-19 outbreak was not different compared to the three-year period preceding the COVID-19 era. In conclusion, in our cohort of patients with prior myocarditis, both COVID-19 infection and vaccination were uneventful.

A New Inherited Syndrome Causing Sudden Cardiac Death with Distinct ST-Segment Depression and Ankyrin-2-Mutation.

Introduction: Sudden cardiac death (SCD) is a serious threat. In individuals under the age of 35 years sudden arrhythmic death is the most frequent cause. In younger persons, genetically determined cardiac diseases (eg, cardiomyopathies and ion-channel diseases) account for an important proportion of these cases. Methods: We investigated the case of a 23-year-old male with SCD, specific ECG changes and left ventricular hypertrophy. Family history was significant for SCD in the paternal line. A precise analysis was performed by an international multidisciplinary expert panel including autopsy of the index patient's heart, molecular autopsy, whole-exome sequencing, analysis of the pedigree and examination of available family members. Results: Three cases of SCD were reported in paternal relatives. The index patient exhibited specific ECG changes (ST-depression), which were also found in five paternal relatives and the brother of the index patient. Post-mortem analysis of the heart yielded mild idiopathic concentric hypertrophy without myocardial disarray. The genetic analysis of the index patient showed two nucleotide variations in two different genes (ANK2: c.11791G>A, MYO18B: c.3761G>A), which were also expressed in five relatives. Two family members had showed all indicators of the inherited syndrome including distinct ECG changes and genetic changes. Conclusion: We describe a distinct inheritable syndrome causing SCD, characterized by specific ECG changes and mutations of ANK2 and MYO18. As far as we know this is the first description of this syndrome.

Clinical profiling and outcomes of viral myocarditis manifesting with ventricular arrhythmias.

Aims: Clinical features and risk stratification of patients with viral myocarditis (VM) complicated by ventricular arrhythmias (VA) are incompletely understood. We aim to describe arrhythmia patterns and outcomes in patients with VM and early-onset VA. Methods and results: We present a single-centre study, enrolling patients with VM proven by endomyocardial biopsy, and evidence of VA within 24 h of hospitalization. The incidence of major adverse events (MAE), including all-cause death, severe heart failure, advanced atrioventricular blocks, or major VA, was evaluated during a 24-month follow-up (FU) and compared with a matched group of virus-negative myocarditis. Of patients with VM (n = 74, mean age 47 ± 16 years, 66% males, and left ventricular ejection fraction 51 ± 13%), 20 (27%) presented with major VA [ventricular tachycardia/ventricular fibrillation (VT/VF)], and 32 (44%) had polymorphic VA. Patients with polymorphic VA more commonly had evidence of ongoing systemic infection (24/32 vs. 10/42, P = 0.004) and experienced greater occurrence of MAE at discharge (15/32 vs. 2/42, P < 0.001). However, the incidence of MAE during FU was higher in patients with monomorphic VA compared to those with polymorphic VA (17/42 vs. 2/28, P = 0.002). Patients with monomorphic VA displayed frequently signs of chronic cardiomyopathy and had outcomes comparable with virus-negative myocarditis (log rank P = 0.929). Presentation with VT/VF was independently associated with MAE [at discharge: hazard ratio (HR) 4.7, 95% confidence interval (CI) 1.6-14.0, P = 0.005; during FU: HR 6.3, 95% CI 2.3-17.6, P < 0.001]. Conclusion: In patients with VM, polymorphic VA point to ongoing systemic infection and early adverse outcomes, whereas monomorphic VA suggest chronic cardiomyopathy and greater incidence of MAE during FU. Presentation with VT/VF is independently associated with MAE.