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.

Genetic Architecture of Acute Myocarditis and the Overlap With Inherited Cardiomyopathy.

BACKGROUND: Acute myocarditis is an inflammatory condition that may herald the onset of dilated cardiomyopathy (DCM) or arrhythmogenic cardiomyopathy (ACM). We investigated the frequency and clinical consequences of DCM and ACM genetic variants in a population-based cohort of patients with acute myocarditis. METHODS: This was a population-based cohort of 336 consecutive patients with acute myocarditis enrolled in London and Maastricht. All participants underwent targeted DNA sequencing for well-characterized cardiomyopathy-associated genes with comparison to healthy controls (n=1053) sequenced on the same platform. Case ascertainment in England was assessed against national hospital admission data. The primary outcome was all-cause mortality. RESULTS: Variants that would be considered pathogenic if found in a patient with DCM or ACM were identified in 8% of myocarditis cases compared with <1% of healthy controls (P=0.0097). In the London cohort (n=230; median age, 33 years; 84% men), patients were representative of national myocarditis admissions (median age, 32 years; 71% men; 66% case ascertainment), and there was enrichment of rare truncating variants (tv) in ACM-associated genes (3.1% of cases versus 0.4% of controls; odds ratio, 8.2; P=0.001). This was driven predominantly by DSP-tv in patients with normal LV ejection fraction and ventricular arrhythmia. In Maastricht (n=106; median age, 54 years; 61% men), there was enrichment of rare truncating variants in DCM-associated genes, particularly TTN-tv, found in 7% (all with left ventricular ejection fraction <50%) compared with 1% in controls (odds ratio, 3.6; P=0.0116). Across both cohorts over a median of 5.0 years (interquartile range, 3.9-7.8 years), all-cause mortality was 5.4%. Two-thirds of deaths were cardiovascular, attributable to worsening heart failure (92%) or sudden cardiac death (8%). The 5-year mortality risk was 3.3% in genotype-negative patients versus 11.1% for genotype-positive patients (Padjusted=0.08). CONCLUSIONS: We identified DCM- or ACM-associated genetic variants in 8% of patients with acute myocarditis. This was dominated by the identification of DSP-tv in those with normal left ventricular ejection fraction and TTN-tv in those with reduced left ventricular ejection fraction. Despite differences between cohorts, these variants have clinical implications for treatment, risk stratification, and family screening. Genetic counseling and testing should be considered in patients with acute myocarditis to help reassure the majority while improving the management of those with an underlying genetic variant.

Indications and utility of cardiac genetic testing in athletes.

Sports Cardiology practice commonly involves the evaluation of athletes for genetically determined cardiac conditions that may predispose to malignant arrhythmias, heart failure, and sudden cardiac death. High-level exercise can lead to electrical and structural cardiac remodelling which mimics inherited cardiac conditions (ICCs). Differentiation between 'athlete's heart' and pathology can be challenging and often requires the whole armamentarium of available investigations. Genetic studies over the last 30 years have identified many of the genetic variants that underpin ICCs and technological advances have transformed genetic testing to a more readily available and affordable clinical tool which may aid diagnosis, management, and prognosis. The role of genetic testing in the evaluation and management of athletes with suspected cardiac conditions is often unclear beyond the context of specialist cardio-genetics centres. This document is aimed at physicians, nurses, and allied health professionals involved in the athlete's care. With the expanding role and availability of genetic testing in mind, this document was created to address the needs of the broader sports cardiology community, most of whom work outside specialized cardio-genetics centres, when faced with the evaluation and management of athletes with suspected ICC. The first part of the document provides an overview of basic terminology and principles and offers guidance on the appropriate use of genetic testing in the assessment of such athletes. It outlines key considerations when contemplating genetic testing, highlighting the potential benefits and pitfalls, and offers a roadmap to genetic testing. The second part of the document presents common clinical scenarios in Sports Cardiology practice, outlining the diagnostic, prognostic, and therapeutic implications of genetic testing, including impact on exercise recommendations. The scope of this document does not extend to a comprehensive description of the genetic basis, investigation, or management of ICCs.

Myocarditis following COVID-19 vaccine: incidence, presentation, diagnosis, pathophysiology, therapy, and outcomes put into perspective. A clinical consensus document supported by the Heart Failure Association of the European Society of Cardiology (ESC) and the ESC Working Group on Myocardial and Pericardial Diseases.

Over 10 million doses of COVID-19 vaccines based on RNA technology, viral vectors, recombinant protein, and inactivated virus have been administered worldwide. Although generally very safe, post-vaccine myocarditis can result from adaptive humoral and cellular, cardiac-specific inflammation within days and weeks of vaccination. Rates of vaccine-associated myocarditis vary by age and sex with the highest rates in males between 12 and 39 years. The clinical course is generally mild with rare cases of left ventricular dysfunction, heart failure and arrhythmias. Mild cases are likely underdiagnosed as cardiac magnetic resonance imaging (CMR) is not commonly performed even in suspected cases and not at all in asymptomatic and mildly symptomatic patients. Hospitalization of symptomatic patients with electrocardiographic changes and increased plasma troponin levels is considered necessary in the acute phase to monitor for arrhythmias and potential decline in left ventricular function. In addition to evaluation for symptoms, electrocardiographic changes and elevated troponin levels, CMR is the best non-invasive diagnostic tool with endomyocardial biopsy being restricted to severe cases with heart failure and/or arrhythmias. The management beyond guideline-directed treatment of heart failure and arrhythmias includes non-specific measures to control pain. Anti-inflammatory drugs such as non-steroidal anti-inflammatory drugs, and corticosteroids have been used in more severe cases, with only anecdotal evidence for their effectiveness. In all age groups studied, the overall risks of SARS-CoV-2 infection-related hospitalization and death are hugely greater than the risks from post-vaccine myocarditis. This consensus statement serves as a practical resource for physicians in their clinical practice, to understand, diagnose, and manage affected patients. Furthermore, it is intended to stimulate research in this area.

Diagnosis and treatment of cardiac amyloidosis. A position statement of the European Society of Cardiology Working Group on Myocardial and Pericardial Diseases.

Cardiac amyloidosis is a serious and progressive infiltrative disease that is caused by the deposition of amyloid fibrils at the cardiac level. It can be due to rare genetic variants in the hereditary forms or as a consequence of acquired conditions. Thanks to advances in imaging techniques and the possibility of achieving a non-invasive diagnosis, we now know that cardiac amyloidosis is a more frequent disease than traditionally considered. In this position paper the Working Group on Myocardial and Pericardial Disease proposes an invasive and non-invasive definition of cardiac amyloidosis, addresses clinical scenarios and situations to suspect the condition and proposes a diagnostic algorithm to aid diagnosis. Furthermore, we also review how to monitor and treat cardiac amyloidosis, in an attempt to bridge the gap between the latest advances in the field and clinical practice.

Diagnosis and treatment of cardiac amyloidosis: a position statement of the ESC Working Group on Myocardial and Pericardial Diseases.

Cardiac amyloidosis is a serious and progressive infiltrative disease that is caused by the deposition of amyloid fibrils at the cardiac level. It can be due to rare genetic variants in the hereditary forms or as a consequence of acquired conditions. Thanks to advances in imaging techniques and the possibility of achieving a non-invasive diagnosis, we now know that cardiac amyloidosis is a more frequent disease than traditionally considered. In this position paper the Working Group on Myocardial and Pericardial Disease proposes an invasive and non-invasive definition of cardiac amyloidosis, addresses clinical scenarios and situations to suspect the condition and proposes a diagnostic algorithm to aid diagnosis. Furthermore, we also review how to monitor and treat cardiac amyloidosis, in an attempt to bridge the gap between the latest advances in the field and clinical practice.

Diagnosis of arrhythmogenic cardiomyopathy: The Padua criteria.

The original designation of "Arrhythmogenic right ventricular (dysplasia/) cardiomyopathy"(ARVC) was used by the scientists who first discovered the disease, in the pre-genetic and pre-cardiac magnetic resonance era, to describe a new heart muscle disease predominantly affecting the right ventricle, whose cardinal clinical manifestation was the occurrence of malignant ventricular arrhythmias. Subsequently, autopsy investigations, genotype-phenotype correlations studies and the increasing use of contrast-enhancement cardiac magnetic resonance showed that the fibro-fatty replacement of the myocardium represents the distinctive phenotypic feature of the disease that affects the myocardium of both ventricles, with left ventricular involvement which may parallel or exceed the severity of right ventricular involvement. This has led to the new designation of "Arrhythmogenic Cardiomyopathy" (ACM), that represents the evolution of the original term of ARVC. The present International Expert Consensus document proposes an upgrade of the criteria for diagnosis of the entire spectrum of the phenotypic variants of ACM. The proposed "Padua criteria" derive from the diagnostic approach to ACM, which has been developed over 30 years by the multidisciplinary team of basic researchers and clinical cardiologists of the Medical School of the University of Padua. The Padua criteria are a working framework to improve the diagnosis of ACM by introducing new diagnostic criteria regarding tissue characterization findings by contrast-enhanced cardiac magnetic resonance, depolarization/repolarization ECG abnormalities and ventricular arrhythmia features for diagnosis of the left ventricular phenotype. The proposed diagnostic criteria need to be further validated by future clinical studies in large cohorts of patients.

Genetic Variants Associated With Cancer Therapy-Induced Cardiomyopathy.

BACKGROUND: Cancer therapy-induced cardiomyopathy (CCM) is associated with cumulative drug exposures and preexisting cardiovascular disorders. These parameters incompletely account for substantial interindividual susceptibility to CCM. We hypothesized that rare variants in cardiomyopathy genes contribute to CCM. METHODS: We studied 213 patients with CCM from 3 cohorts: retrospectively recruited adults with diverse cancers (n=99), prospectively phenotyped adults with breast cancer (n=73), and prospectively phenotyped children with acute myeloid leukemia (n=41). Cardiomyopathy genes, including 9 prespecified genes, were sequenced. The prevalence of rare variants was compared between CCM cohorts and The Cancer Genome Atlas participants (n=2053), healthy volunteers (n=445), and an ancestry-matched reference population. Clinical characteristics and outcomes were assessed and stratified by genotypes. A prevalent CCM genotype was modeled in anthracycline-treated mice. RESULTS: CCM was diagnosed 0.4 to 9 years after chemotherapy; 90% of these patients received anthracyclines. Adult patients with CCM had cardiovascular risk factors similar to the US population. Among 9 prioritized genes, patients with CCM had more rare protein-altering variants than comparative cohorts ( P≤1.98e-04). Titin-truncating variants (TTNtvs) predominated, occurring in 7.5% of patients with CCM versus 1.1% of The Cancer Genome Atlas participants ( P=7.36e-08), 0.7% of healthy volunteers ( P=3.42e-06), and 0.6% of the reference population ( P=5.87e-14). Adult patients who had CCM with TTNtvs experienced more heart failure and atrial fibrillation ( P=0.003) and impaired myocardial recovery ( P=0.03) than those without. Consistent with human data, anthracycline-treated TTNtv mice and isolated TTNtv cardiomyocytes showed sustained contractile dysfunction unlike wild-type ( P=0.0004 and P<0.002, respectively). CONCLUSIONS: Unrecognized rare variants in cardiomyopathy-associated genes, particularly TTNtvs, increased the risk for CCM in children and adults, and adverse cardiac events in adults. Genotype, along with cumulative chemotherapy dosage and traditional cardiovascular risk factors, improves the identification of patients who have cancer at highest risk for CCM. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01173341; AAML1031; NCT01371981.

Ablation compared with drug therapy for recurrent ventricular tachycardia in arrhythmogenic right ventricular cardiomyopathy: Results from a multicenter study.

BACKGROUND: The comparative efficacy of antiarrhythmic drug (AAD) therapy vs ventricular tachycardia (VT) ablation in arrhythmogenic right ventricular cardiomyopathy (ARVC) is unknown. OBJECTIVE: We compared outcomes of AAD and/or ß-blocker (BB) therapy with those of VT ablation (with AAD/BB) in patients with ARVC who had recurrent VT. METHODS: In a multicenter retrospective study, 110 patients with ARVC (mean age 38 ± 17 years; 91[83%] men) with a minimum of 3 VT episodes were included; 77 (70%) were initially treated with AAD/BB and 32 (29%) underwent ablation. Subsequently, 43 of the 77 patients treated with AAD/BB alone also underwent ablation. Overall, 75 patients underwent ablation. RESULTS: When comparing initial AAD/BB therapy (n = 77) and VT ablation (n = 32) after ≥3 VT episodes, a single ablation procedure rendered 35% of patients free of VT at 3 years compared with 28% of AAD/BB-only-treated patients (P = .46). Of the 77 AAD/BB-only-treated patients, 43 subsequently underwent ablation. For all 75 patients who underwent ablation, 56% were VT-free at 3 years after the last ablation procedure. Epicardial ablation was used in 40/75 (53%) and was associated with lower VT recurrence after the last ablation procedure (endocardial/epicardial vs endocardial-only; 71% vs 47% 3-year VT-free survival; P = .05). Importantly, there was no difference in survival free of death or transplantation between the ablation- and AAD/BB-only-treated patients (P = .61). CONCLUSION: In patients with ARVC and a high VT burden, mortality and transplantation-free survival are not significantly different between drug- and ablation-treated patients. These patients have a high risk of recurrent VT despite drug therapy. Combined endocardial/epicardial ablation is associated with reduced VT recurrence as compared with endocardial-only ablation.

Individualized surgical strategies for left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

OBJECTIVES: Surgical strategies to treat drug refractory left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy include septal myectomy (SM) and, less frequently, mitral valve (MV) repair or replacement. The primary aim of this study was to report the surgical technique and management outcomes in a consecutive group of patients with variable phenotypes of hypertrophic cardiomyopathy in a broad national specialist practice. METHODS: A total of 203 consecutive patients, 132 men (mean age 48.6 ± 14.6 years) underwent surgery for the management of LVOTO. Surgical approaches included SM (n = 159), SM with MV repair (n = 25), SM with MV replacement (n = 9) and MV replacement alone (n = 10). Specific surgical approaches were performed based on the underlying mechanism of obstruction. Eleven (5.4%) patients had previous alcohol septal ablation for the management of LVOTO. Concomitant non-mitral cardiac procedures were carried out in 22 (10.8%) patients. RESULTS: Operative survival rate was 99.0% with 2 deaths within 30 days. The mean bypass time was 92.9 ± 47.8 min, with a mean length of hospital stay of 10.5 ± 7.8 days. Surgical complications included 3 ventricular septal defects requiring repair (1.5%), 1 Gerbode defect surgically repaired, 2 aortic valve repairs (1.0%), 2 transient ischaemic attacks (1.0%) and 4 strokes (2.0%). Thirty-nine (19.2%) patients had perioperative new-onset atrial fibrillation and 8 (3.9%) patients had unexpected atrioventricular block requiring a permanent pacemaker. Mean resting left ventricular outflow tract gradient improved from 70.6 ± 40.3 mmHg preoperatively to 11.0 ± 10.5 mmHg at 1 year postoperatively (P < 0.001). Mean New York Heart Association class improved from 2.6 ± 0.5 preoperatively to 1.6 ± 0.6 at 1 year after the procedure. CONCLUSIONS: In variable phenotypes of LVOTO in hypertrophic cardiomyopathy, an individualized surgical approach provided effective reductions in left ventricular outflow tract gradients and good symptomatic relief with acceptable mortality and morbidity.

Early and medium-term outcomes of Alfieri mitral valve repair in the management of systolic anterior motion during septal myectomy.

BACKGROUND: This report studies the early and medium-term clinical and echocardiographic outcomes of the Alfieri edge-to-edge mitral valve repair, as adjunctive therapy, to prevent and treat systolic anterior motion (SAM) at the time of septal myectomy (SM) for left ventricular outflow tract obstruction in hypertrophic cardiomyopathy. METHODS: From 2009-2015, 11 consecutive patients had a trans-atrial Alfieri repair, to prevent (n = 7) or treat (n = 4) SAM at the time of SM. RESULTS: No patients were lost to follow-up. There were no perioperative or late deaths. Pre-bypass, the mean left ventricular outflow tract gradient, measured directly by simultaneous needle insertion, was 40.7 ± 19.9 mmHg at rest and 115.8 ± 30.4 mmHg on provocation with Isoproterenol, which reduced after SM and Alfieri repair and discontinuation of bypass, to a mean gradient of 8.3 ± 9.8 mmHg at rest and 25.8 ± 9.2 mmHg on provocation. One patient who required mitral valve replacement on day 4, was hospitalized at 2.7 years with heart failure requiring diuresis and remains well at 6 years. One patient developed postoperative atrial fibrillation. There were no other early or late complications. At a median follow-up of 6.6 years (international quartile range 1.2-7.4), clinical and echocardiographic data demonstrated maintained improvement in mean New York Heart Association class from 2.6 ± 0.9 preoperatively to 1.7 ± 0.4 and reduction in mean grade of mitral regurgitation from 2.7 ± 0.8 preoperatively to 0.7 ± 0.6. CONCLUSIONS: The Alfieri repair, as adjunctive therapy, for the prevention or treatment of SAM at the time of SM demonstrates satisfactory early and medium-term clinical and echocardiographic outcomes supporting the ongoing utility of this approach.

Electrical and Structural Substrate of Arrhythmogenic Right Ventricular Cardiomyopathy Determined Using Noninvasive Electrocardiographic Imaging and Late Gadolinium Magnetic Resonance Imaging.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a significant cause of sudden cardiac death in the young. Improved noninvasive assessment of ARVC and better understanding of the disease substrate are important for improving patient outcomes. METHODS AND RESULTS: We studied 20 genotyped ARVC patients with a broad spectrum of disease using electrocardiographic imaging (a method for noninvasive cardiac electrophysiology mapping) and advanced late gadolinium enhancement cardiac magnetic resonance scar imaging. Compared with 20 healthy controls, ARVC patients had longer ventricular activation duration (median, 52 versus 42 ms; P=0.007) and prolonged mean epicardial activation-recovery intervals (a surrogate for local action potential duration; median, 275 versus 241 ms; P=0.014). In these patients, we observed abnormal and varied epicardial activation breakthrough locations and regions of nonuniform conduction and fractionated electrograms. Nonuniform conduction and fractionated electrograms were present in the early concealed phase of ARVC. Electrophysiological abnormalities colocalized with late gadolinium enhancement scar, indicating a relationship with structural disease. Premature ventricular contractions were common in ARVC patients with variable initiation sites in both ventricles. Premature ventricular contraction rate increased with exercise, and within anatomic segments, it correlated with prolonged repolarization, electric markers of scar, and late gadolinium enhancement (all P<0.001). CONCLUSIONS: Electrocardiographic imaging reveals electrophysiological substrate properties that differ in ARVC patients compared with healthy controls. A novel mechanistic finding is the presence of repolarization abnormalities in regions where ventricular ectopy originates. The results suggest a potential role for electrocardiographic imaging and late gadolinium enhancement in early diagnosis and noninvasive follow-up of ARVC patients.

Desmoplakin missense and non-missense mutations in arrhythmogenic right ventricular cardiomyopathy: Genotype-phenotype correlation.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is traditionally considered as primarily affecting the right ventricle. Mutations in genes encoding desmosomal proteins account for 40-60% of cases. Genotype-phenotype correlations are scant and mostly non gene-specific. Accordingly, we assessed the genotype-phenotype correlation for desmoplakin (DSP) missense and non-missense mutations causing ARVC. METHODS AND RESULTS: We analyzed 27 ARVC patients carrying a missense or a non-missense DSP mutation, with complete clinical assessment. The two groups were compared for clinical parameters, basic demographics such as sex, age at diagnosis, age at disease onset, as well as prevalence of symptoms and arrhythmic events. Missense DSP variants were present in 10 patients and non-missense in 17. Mean age at diagnosis and at first arrhythmic event did not differ between the two groups. Also the prevalence of symptoms, either major (60% vs 59%, p=1) or all (80% vs 88%, p=0.61), did not differ. By contrast, left ventricular (LV) dysfunction was significantly more prevalent among patients with non-missense mutations (76.5% vs 10%, p=0.001), who were also much more likely to have a structural LV involvement by Cardiac Magnetic Resonance (CMR) (92% vs 22%, p=0.001). CONCLUSIONS: For ARVC patients, both missense and non-missense DSP mutations carry a high arrhythmic risk. Non-missense mutations are specifically associated with left-dominant forms. The presence of DSP non-missense mutations should alert to the likely development of LV dysfunction. These findings highlight the clinical relevance of genetic testing even after the clinical diagnosis of ARVC and the growing clinical impact of genetics.

Relationship between aetiology and left ventricular systolic dysfunction in hypertrophic cardiomyopathy.

BACKGROUND: Severe left ventricular (LV) systolic dysfunction is an uncommon complication of hypertrophic cardiomyopathy (HCM) that is associated with poor prognosis. Small observational series suggest that patients with rare causes of HCM are more likely to develop systolic impairment than those with idiopathic disease or mutations in cardiac sarcomeric protein genes. The aim of this study was to test this hypothesis by comparing the prevalence of systolic dysfunction and its impact on prognosis in patients with different causes of HCM. METHODS AND RESULTS: 1697 patients (52 (40-63) years, 1160 (68%) males) with HCM followed at two European referral centres were studied. Diagnosis of specific aetiologies was made on the basis of clinical examination, cardiac imaging and targeted genetic and biochemical testing. The primary survival outcome was all-cause mortality or heart transplantation (HTx) for end-stage heart failure (HF). Secondary outcomes were HF-related death, sudden cardiac death, stroke-related death and non-cardiovascular death. Systolic dysfunction (LV ejection fraction <50% by two-dimensional (2D) echocardiography) at first evaluation was more frequent in rare phenocopies than in idiopathic or sarcomeric HCM (105/409 (26%) vs 40/1288 (3%), respectively (p<0.0001)). All-cause death/HTx and HF-related death were more frequent in rare phenocopies compared with idiopathic or sarcomeric HCM (p<0.0001). All-cause mortality and HF-related death were highest in patients with cardiac amyloidosis (p<0.0001). CONCLUSIONS: In adults with HCM, LV systolic dysfunction is more frequent in those with rare phenocopies. When combined with age at presentation, it is a marker for specific aetiologies and is associated with poorer long-term survival.

The ventricular ectopic QRS interval (VEQSI): Diagnosis of arrhythmogenic right ventricular cardiomyopathy in patients with incomplete disease expression.

BACKGROUND: The ventricular ectopic QRS interval (VEQSI) has been shown to identify structural heart disease and predict mortality. In arrhythmogenic right ventricular cardiomyopathy (ARVC), early diagnosis is difficult using current methods, and life-threatening arrhythmias are common and difficult to predict. OBJECTIVE: The purpose of this study was to assess the utility of ventricular ectopic indices including VEQSI in ARVC diagnosis. METHODS: We studied 70 patients with ARVC [30 with definite disease (age 47 ± 12 years; 60% male), 40 with incomplete disease expression (age 44 ± 18 years; 44% male)], 116 healthy controls (age 40 ± 15 years; 56% male), and 26 patients with normal heart right ventricular outflow tract (RVOT) ectopy (age 46 ± 17 years; 27% male). The duration of the broadest ventricular ectopic beat during 12-lead Holter monitoring was recorded as VEQSI max. RESULTS: VEQSI max was associated with age and gender, but not with conducted QRS duration. Adjusted VEQSI max was greater in ARVC patients than in control groups. In healthy males (44.5 years), estimated VEQSI max was 163 ms (95% confidence interval [CI] 159-167 ms); in definite ARVC 212 ms (95% CI 206-217 ms); in incompletely expressed ARVC 204 ms (95% CI 199-210 ms); and in normal heart RVOT ectopy 171 ms (95% CI 165-178 ms). VEQSI max >180 ms had 98% sensitivity and specificity for diagnosis of ARVC (area under the curve 0.99, 95% CI 0.980-0.998). In our incompletely expressed ARVC patients, VEQSI max >180 ms identified 88% as affected. CONCLUSION: VEQSI max distinguishes ARVC patients, including those with incomplete disease expression, from healthy controls and patients with normal heart RVOT ectopy.

Diagnosis and management of hypertrophic cardiomyopathy.

The clinical spectrum of hypertrophic cardiomyopathy (HCM) is complex and includes a variety of phenotypes, which leads to different types of manifestations. Although most of the patients are asymptomatic, a significant proportion of them will develop symptoms or risk of arrhythmias and sudden cardiac death (SCD). Therefore, the objectives of HCM diagnosis and management are to relieve the patients' symptoms (chest pain, heart failure, syncope, palpitations, etc.), prevent disease progression and major cardiovascular complications and SCD. The heterogeneity of HCM patterns, their symptoms and assessment is a challenge for the cardiologist.