Stage-specific therapy for hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most common inherited myocardial disease and is defined by otherwise unexplained left ventricular hypertrophy. The main complications include heart failure and arrhythmias such as atrial fibrillation and ventricular arrhythmias. Current treatment rests on septal reduction therapies, prevention of sudden cardiac death through implantable cardioverter defibrillator, and use of drugs such as beta-blockers, calcium antagonists, or amiodarone. In the last years, new pharmacological agents specifically targeting the pathophysiology of the disease have been developed with encouraging results in terms of functional capacity and symptoms improvement from clinical trials. In this review, we summarize the possible treatment approaches for each phase of the natural history of the disease: pre-phenotype expression, classic phenotype, adverse remodelling, and overt dysfunction.

Coronary microvascular function is impaired in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

BACKGROUND AND PURPOSE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare inherited disease caused by NOTCH3 gene mutations. Although the main clinical features reflect brain injury, CADASIL is a systemic microangiopathy, and cardiac involvement has been observed but not systematically assessed. We aimed to study the prevalence and severity of coronary microvascular dysfunction (CMD) in CADASIL patients. METHODS: Seventeen patients with genetically confirmed CADASIL, aged <60 years (mean age 40 ± 9 years), with ≤1 cardiovascular risk factor underwent neurological and neuropsychological evaluation, 3T brain magnetic resonance imaging (MRI), 12-lead electrocardiography (ECG), standard echocardiography, and measurement of myocardial blood flow at rest (resting MBF) and of maximal myocardial blood flow following Regadenoson infusion (Reg-MBF) by 13 NH3 positron emission tomography (PET). Coronary flow reserve (CFR) was defined as Reg-MBF/resting MBF. PET results were compared to those of 15 healthy controls who were age and sex matched. RESULTS: Twelve patients (71%) presented migraine, none (53%) had psychiatric disturbances, and one (6%) had a previous stroke. None had cognitive impairment or ECG or echocardiography abnormalities. Both Reg-MBF and CFR were blunted in CADASIL patients compared with controls (Reg-MBF 2.46 ± 0.54 vs. 3.09 ± 0.44 ml/g/min, respectively; p < 0.01; CFR 2.74 ± 0.36 vs. 3.28 ± 0.66, respectively, p < 0.01). No correlations were found between Reg-MBF values and neuropsychological performance or cerebral lesion burden on MRI. CONCLUSIONS: CADASIL patients exhibit blunted CFR due to CMD, which can be severe and is independent of the severity of brain lesion load and cognitive performances. CADASIL is a systemic microcirculation disease, and active surveillance of cardiac symptoms should be considered in these patients.

Mavacamten, a Novel Therapeutic Strategy for Obstructive Hypertrophic Cardiomyopathy.

PURPOSE OF REVIEW: Pharmacological treatment options for hypertrophic cardiomyopathy (HCM) are currently limited and comprise non-disease specific therapies such as ß-blockers, non-dihydropyridine calcium channel blockers, and disopyramide. These agents that offer a variable degree of symptomatic relief, often suboptimal, are often limited by side-effects and fail to address the key molecular abnormalities of the disease. RECENT FINDINGS: Mavacamten is a novel, first-in-class, allosteric inhibitor of cardiac myosin ATPase, which reduces actin-myosin cross-bridge formation, thereby reducing myocardial contractility and improving myocardial energetic consumption in experimental HCM models. Following a successful Phase 2 study, the recently published phase III, placebo-controlled, randomized EXPLORER-HCM trial demonstrated the efficacy and safety of mavacamten in reducing left ventricular outflow tract obstruction and ameliorating exercise capacity, New York Heart Association functional class and health status in patients with obstructive HCM. Mavacamten represents the first agent specifically developed for HCM successfully tested in a Phase III trial, to be registered soon for clinical use, representing a radical change of paradigm in the pharmacological treatment of HCM.

Targeted Medical Therapies for Hypertrophic Cardiomyopathy.

PURPOSE OF REVIEW: The management of hypertrophic cardiomyopathy (HCM) has changed considerably over the years, although molecular therapies targeting core mechanisms of the disease are still lacking. This review provides an overview of the contemporary medical approach to patients with HCM, and of promising novel developments hopefully soon to enter the clinical arena. RECENT FINDINGS: Our perception of therapeutic targets for medical therapy in HCM is rapidly evolving. Novel approaches include myocardial metabolic modulation, late sodium current inhibition, and allosteric myosin inhibition, actively pursued to reduce and hopefully prevent the development of severe HCM phenotypes, improve symptom control, and preserve patients from disease-related complications. Clinical management of patients with HCM should be guided by in-depth knowledge of the complex mechanisms at the energetic, metabolic, and electrophysiologic level. Until new experimental therapies become available, tailored management of modifiable disease manifestations should be pursued, including lifestyle counseling and prevention of comorbidities.

Cardiovascular magnetic resonance myocardial feature tracking using a non-rigid, elastic image registration algorithm: assessment of variability in a real-life clinical setting.

BACKGROUND: Cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) is a promising technique for quantification of myocardial strain from steady-state free precession (SSFP) cine images. We sought to determine the variability of CMR-FT using a non-rigid elastic registration algorithm recently available in a commercial software package (Segment, Medviso) in a real-life clinical setting. METHODS: Firstly, we studied the variability in a healthy volunteer who underwent 10 CMR studies over five consecutive days. Secondly, 10 patients were selected from our CMR database yielding normal findings (normal group). Finally, we prospectively studied 10 patients with known or suspected myocardial pathology referred for further investigation to CMR (patient group). In the patient group a second study was performed respecting an interval of 30 min between studies. All studies were manually segmented at the end-diastolic phase by three observers. In all subjects left ventricular (LV) circumferential and radial strain were calculated in the short-axis direction (EccSAX and ErrSAX, respectively) and longitudinal strain in the long-axis direction (EllLAX). The level of CMR experience of the observers was 2 weeks, 6 months and >20 years. RESULTS: Mean contouring time was 7 ± 1 min, mean FT calculation time 13 ± 2 min. Intra- and inter-observer variability was good to excellent with an coefficient of reproducibility (CR) ranging 1.6% to 11.5%, and 1.7% to 16.0%, respectively and an intraclass correlation coefficient (ICC) ranging 0.89 to 1.00 and 0.74 to 0.99, respectively. Variability considerably increased in the test-retest setting with a CR ranging 4.2% to 29.1% and an ICC ranging 0.66 to 0.95 in the patient group. Variability was not influenced by level of expertise of the observers. Neither did the presence of myocardial pathology at CMR negatively impact variability. However, compared to global myocardial strain, segmental myocardial strain variability increased with a factor 2-3, in particular for the basal and apical short-axis slices. CONCLUSIONS: CMR-FT using non-rigid, elastic registration is a reproducible approach for strain analysis in patients routinely scheduled for CMR, and is not influenced by the level of training. However, further improvement is needed to reliably depict small variations in segmental myocardial strain.

Cancer Treatment-Related Complications in Patients With Hypertrophic Cardiomyopathy.

OBJECTIVE: To describe the potential clinical cardiotoxicity of oncological treatments in a cohort of consecutive patients with hypertrophic cardiomyopathy (HCM), systematically followed-up at two national referral centers for HCM. Cardiotoxicity relates to the direct effects of cancer-related treatment on heart function, commonly presenting as left ventricular contractile dysfunction. However, limited data are available regarding cardiotoxic effects on HCM as most studies have not specifically analyzed the effects of oncological treatment in HCM populations. This gap in knowledge may lead to unjustified restriction of HCM patients from receiving curative cancer treatments. METHODS: We retrospectively analyzed clinical and instrumental data of all consecutive HCM patients who underwent oncological treatment between January 2000 and December 2020 collected in a centralized database. RESULTS: Of 3256 HCM patients, 121 (3.7%) had cancer; 110 (90.9%) underwent oncological surgery, 45 (37.2%) received chemotherapy, and 22 (18.2%) received chest radiation therapy (cRT). After a median follow-up of 5.2 years (Q1-Q3: 2-13 years) from oncological diagnosis, 32 patients died. The cumulative survival at 5 years was 79.9%. The cause of death was mainly attributed to the oncological condition, whereas four patients died of sudden cardiac death without receiving previous chemotherapy or cRT. No patient interrupted or reduced the dose of oncological treatment due to cardiac dysfunction. No sustained ventricular tachyarrhythmia was induced by chemotherapy or radiation therapy. CONCLUSION: Cancer treatment was well tolerated in HCM patients. In our consecutive series, none died of cardiovascular complications induced by chemotherapy or cRT and they did not require interruption or substantial treatment tapering due to cardiovascular toxic effects. Although a multidisciplinary evaluation is necessary and regimens must be tailored individually, the diagnosis of HCM per se should not be considered a contraindication to receive optimal curative cancer treatment.

Impact of pregnancy on the natural history of women with hypertrophic cardiomyopathy.

AIMS: Whether pregnancy is a modifier of the long-term course and outcome of women with hypertrophic cardiomyopathy (HCM) is unknown. We assessed the association of pregnancy with long-term outcomes in HCM women. METHODS AND RESULTS: Retrospective evaluation of women with HCM from 1970 to 2021. Only women with pregnancy-related information (pregnancy present or absent) and a follow-up period lasting ≥1 year were included. The peri-partum period was defined as -1 to 6 months after delivery. The primary endpoint was a composite for major adverse cardiovascular events [MACE: cardiovascular death, sudden cardiac death, appropriate defibrillator shock and heart failure (HF) progression]. Overall, 379 (58%) women were included. There were 432 pregnancies in 242 (63%) patients. In 29 (7.6%) cases, pregnancies (n = 39) occurred after HCM diagnosis. Among these, three carrying likely pathogenic sarcomeric variants suffered MACEs in the peri-partum period. At 10 ± 9 years of follow-up, age at diagnosis [hazard ratio (HR) 1.034, 95% confidence interval (CI) 1.018-1.050, P < 0.001] and New York Heart Association (NYHA) class (II vs. I: HR 1.944, 95% CI 0.896-4.218; III vs. I: HR 5.291, 95% CI 2.392-11.705, P < 0.001) were associated with MACE. Conversely, pregnancy was associated with reduced risk (HR 0.605; 95% CI 0.380-0.963, P = 0.034). Among women with pregnancy, multiple occurrences did not modify risk. CONCLUSIONS: Pregnancy is not a modifier of long-term outcome in women with HCM and mostly occurs before a cardiac diagnosis. Most patients tolerate pregnancy well and do not show a survival disadvantage compared to women without. Pregnancy should not be discouraged, except in the presence of severe HF symptoms or high-risk features.

Hypertrophic cardiomyopathy (HCM) is the most common genetic disorder of the myocardium and is characterized by important gender-related differences: women are typically 5 years older than men at diagnosis, over half are diagnosed >50 years of age and consistently show greater propensity than men for heart failure (HF)-related complications and adverse outcome. Whether pregnancy is a modifier of the long-term course and outcome of women with HCM is unknown. In this study, pregnancy was not a modifier of long-term outcome in women with HCM. In particular: At 10 ± 7 years, most patients tolerated pregnancy well and did not show a survival disadvantage compared to women without pregnancies. Only baseline heart failure symptoms and age were associated with adverse outcome.Pregnancy should not be discouraged, except in the presence of severe HF symptoms or high-risk features. Nevertheless, cardio-obstetric counselling and close supervision are key in all instances, particularly in the peri-partum period.

Real-world candidacy to mavacamten in a contemporary hypertrophic obstructive cardiomyopathy population.

AIMS: In the EXPLORER-HCM trial, mavacamten reduced left ventricular outflow tract obstruction (LVOTO) and improved functional capacity of symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients. We sought to define the potential use of mavacamten by comparing real-world HOCM patients with those enrolled in EXPLORER-HCM and assessing their eligibility to treatment. METHODS AND RESULTS: We collected information on HOCM patients followed up at 25 Italian HCM outpatient clinics and with significant LVOTO (i.e. gradient ≥30 mmHg at rest or ≥50 mmHg after Valsalva manoeuvre or exercise) despite pharmacological or non-pharmacological therapy. Pharmacological or non-pharmacological therapy resolved LVOTO in 1044 (61.2%) of the 1706 HOCM patients under active follow-up, whereas 662 patients (38.8%) had persistent LVOTO. Compared to the EXPLORER-HCM trial population, these real-world HOCM patients were older (62.1 ± 14.3 vs. 58.5 ± 12.2 years, p = 0.02), had a lower body mass index (26.8 ± 5.3 vs. 29.7 ± 4.9 kg/m2 , p < 0.0001) and a more frequent history of atrial fibrillation (21.5% vs. 9.8%, p = 0.027). At echocardiography, they had lower left ventricular ejection fraction (LVEF, 66 ± 7% vs. 74 ± 6%, p < 0.0001), higher left ventricular outflow tract gradients at rest (60 ± 27 vs. 52 ± 29 mmHg, p = 0.003), and larger left atrial volume index (49 ± 16 vs. 40 ± 12 ml/m2 , p < 0.0001). Overall, 324 (48.9%) would have been eligible for enrolment in the EXPLORER-HCM trial and 339 (51.2%) for treatment with mavacamten according to European guidelines. CONCLUSIONS: Real-world HOCM patients differ from the EXPLORER-HCM population for their older age, lower LVEF and larger atrial volume, potentially reflecting a more advanced stage of the disease. About half of real-world HOCM patients were found eligible to mavacamten.

Role of cardiovascular magnetic resonance in the clinical evaluation of left ventricular hypertrophy: a 360° panorama.

Left ventricular hypertrophy (LVH) is a frequent imaging finding in the general population. In order to identify the precise etiology, a comprehensive diagnostic approach should be adopted, including the prevalence of each entity that may cause LVH, family history, clinical, electrocardiographic and imaging findings. By providing a detailed evaluation of the myocardium, cardiovascular magnetic resonance (CMR) has assumed a central role in the differential diagnosis of left ventricular hypertrophy, with the technique of parametric imaging allowing more refined tissue characterization. This article aims to establish a parallel between pathophysiological features and imaging findings through the broad spectrum of LVH entities, emphasizing the role of CMR in the differential diagnosis.

[Therapeutic approaches in hypertrophic cardiomyopathy: from symptom relief to precision therapy]. / Approcci terapeutici nella cardiomiopatia ipertrofica: dal controllo dei sintomi alla terapia di precisione.

Hypertrophic cardiomyopathy is the most common genetic cardiomyopathy. Main complications include the development of arrhythmias and heart failure, and the latter may be triggered by left ventricular outflow tract obstruction. The treatment of left ventricular outflow tract obstruction includes pharmacological therapies (beta-blockers, calcium channel blockers, disopyramide) and septal reduction therapies (alcohol septal ablation, surgical myectomy). Myosin inhibitors represent a new therapeutic opportunity and in recent clinical trials proved effective in symptom relief, improvement of functional capacity and quality of life in patients with obstructive hypertrophic cardiomyopathy. In this narrative review we will summarize the available and under development therapeutic approaches for hypertrophic cardiomyopathy.

Genetic Testing and Counselling in Hypertrophic Cardiomyopathy: Frequently Asked Questions.

Genetic counselling and genetic testing in hypertrophic cardiomyopathy (HCM) represent an integral part of the diagnostic algorithm to confirm the diagnosis, distinguish it from phenocopies, and suggest tailored therapeutic intervention strategies. Additionally, they enable cascade genetic testing in the family. With the implementation of Next Generation Sequencing technologies (NGS), the interpretation of genetic data has become more complex. In this regard, cardiologists play a central role, aiding geneticists to correctly evaluate the pathogenicity of the identified genetic alterations. In the ideal setting, geneticists and cardiologists must work side by side to diagnose HCM as well as convey the correct information to patients in response to their many questions and concerns. After a brief overview of the role of genetics in the diagnosis of HCM, we present and discuss the frequently asked questions by HCM patients throughout our 20-year genetic counselling experience. Appropriate communication between the team and the families is key to the goal of delivering the full potential of genetic testing to our patients.

Safety and efficacy of ranolazine in hypertrophic cardiomyopathy: Real-world experience in a National Referral Center.

OBJECTIVES: We assessed the efficacy and safety of ranolazine in real-world patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Ranolazine is an anti-anginal drug that inhibits the late phase of the inward sodium current. In a small prospective trial, ranolazine reduced the arrhythmic burden and improved biomarker profile in HCM patients. However, systematic reports reflecting real-world use in this setting are lacking. METHODS: Changes in clinical and instrumental features, symptoms and arrhythmic burden were evaluated in 119 patients with HCM before and during treatment with ranolazine at a national referral centre for HCM. RESULTS: Patients were treated with ranolazine for 2 [1-4] years; 83 (70%) achieved a dosage ≥1000 mg per day. Treatment interruption was necessary in 24 patients (20%) due to side effects (n = 10, 8%) or disopyramide initiation (n = 8, 7%). Seventy patients (59%) were treated with ranolazine for relief of angina. Among them, 51 (73%) had total symptomatic relief and 47 patients (67%) showed ≥2 Canadian Cardiovascular society (CCS) angina grade improvement. Sixteen patients (13%) were treated for recurrent ventricular arrhythmias, including 4 with a clear ischemic trigger, who experienced no further arrhythmic episodes while on ranolazine. Finally, 33 patients (28%) were treated for heart failure associated with severe diastolic dysfunction: no symptomatic benefit could be observed in this group. CONCLUSION: Ranolazine was safe and well tolerated in patients with HCM. The use of ranolazine may be considered in patients with HCM and microvascular angina.

Focus on Paediatric Restrictive Cardiomyopathy: Frequently Asked Questions.

Restrictive cardiomyopathy (RCM) is characterized by restrictive ventricular pathophysiology determined by increased myocardial stiffness. While suspicion of RCM is initially raised by clinical evaluation and supported by electrocardiographic and echocardiographic findings, invasive hemodynamic evaluation is often required for diagnosis and management of patients during follow-up. RCM is commonly associated with a poor prognosis and a high incidence of heart failure, and PH is reported in paediatric patients with RCM. Currently, only a few therapies are available for specific RCM aetiologies. Early referral to centres for advanced heart failure treatment is often necessary. The aim of this review is to address questions frequently asked when facing paediatric patients with RCM, including issues related to aetiologies, clinical presentation, diagnostic process and prognosis.

Emerging Medical Treatment for Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a common myocardial disease characterized by otherwise unexplained left ventricular hypertrophy. The main cause of disabling symptoms in patients with HCM is left ventricular outflow tract (LVOT) obstruction. This phenomenon is multifactorial, determined both by anatomical and functional abnormalities: myocardial hypercontractility is believed to represent one of its major determinants. The anatomical anomalies are targeted by surgical interventions, whereas attenuating hypercontractility is the objective of old and new drugs including the novel class of allosteric myosin inhibitors. This review summarizes the current treatment modalities and discusses the emerging therapeutical opportunities focusing on the recently developed cardiac myosin ATPase inhibitors Mavacamten and CK-274. Novel surgical and interventional approaches are also discussed.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome): Prospective evaluation at a tertiary referral centre.

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic vasculitis. Cardiac specific involvement (CSI) is caused by coronary artery vasculitis, but also by myocardial eosinophilic infiltration. To date, the prevalence of CSI associated with EGPA is unresolved. Aim of this study was to systematically assess the prevalence and clinical impact of CSI in a consecutive outpatient EGPA population. METHODS: Between October 2018 and July 2019, we prospectively enrolled 52 consecutive EGPA patients. All underwent comprehensive evaluation including a standardized questionnaire, physical examination, 12-lead-ECG, echocardiography. Cardiac magnetic resonance and 24 h-Holter were performed as deemed clinically appropriate. Cardiac abnormalities were defined as CSI based on the likelihood of their relation to EGPA vasculitis, after exclusion of alternative diagnoses. RESULTS: 52 enrolled patients, mean age 59±1 years. Thirteen of the 52 patients (25%) were classified as CSI+. CSI was characterized by myocarditis in four patients, non-scar-related regional wall motions abnormalities (RWMA) in three, apical thrombosis in two (one also had RWMA), pericarditis in three and non-atherosclerotic coronary disease (Prinzmetal angina and coronaritis) in 2. Five (38%) of the 13 CSI+ patients, presented an apical aneurysm. Peak eosinophil count at diagnosis was higher in CSI+: 8000 /µl vs CSI-: 3000 /µl, p = 0.017. Overall, 2 patients had severe LV dysfunction, 5 required urgent hospitalization and 8 required long-term cardioactive therapy. CONCLUSIONS: CSI was present in one-quarter of patients, often associated with high peak eosinophils. Myocarditis, RWMA and apical aneurysms were the most common manifestations. Although rarely severe and life-threatening, CSI often required long-term cardioactive treatment.

Maximal Wall Thickness Measurement in Hypertrophic Cardiomyopathy: Biomarker Variability and its Impact on Clinical Care.

OBJECTIVES: The aim of this study was to define the variability of maximal wall thickness (MWT) measurements across modalities and predict its impact on care in patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Left ventricular MWT measured by echocardiography or cardiovascular magnetic resonance (CMR) contributes to the diagnosis of HCM, stratifies risk, and guides key decisions, including whether to place an implantable cardioverter-defibrillator (ICD). METHODS: A 20-center global network provided paired echocardiographic and CMR data sets from patients with HCM, from which 17 paired data sets of the highest quality were selected. These were presented as 7 randomly ordered pairs (at 6 cardiac conferences) to experienced readers who report HCM imaging in their daily practice, and their MWT caliper measurements were captured. The impact of measurement variability on ICD insertion decisions was estimated in 769 separately recruited multicenter patients with HCM using the European Society of Cardiology algorithm for 5-year risk for sudden cardiac death. RESULTS: MWT analysis was completed by 70 readers (from 6 continents; 91% with >5 years' experience). Seventy-nine percent and 68% scored echocardiographic and CMR image quality as excellent. For both modalities (echocardiographic and then CMR results), intramodality inter-reader MWT percentage variability was large (range -59% to 117% [SD ±20%] and -61% to 52% [SD ±11%], respectively). Agreement between modalities was low (SE of measurement 4.8 mm; 95% CI 4.3 mm-5.2 mm; r = 0.56 [modest correlation]). In the multicenter HCM cohort, this estimated echocardiographic MWT percentage variability (±20%) applied to the European Society of Cardiology algorithm reclassified risk in 19.5% of patients, which would have led to inappropriate ICD decision making in 1 in 7 patients with HCM (8.7% would have had ICD placement recommended despite potential low risk, and 6.8% would not have had ICD placement recommended despite intermediate or high risk). CONCLUSIONS: Using the best available images and experienced readers, MWT as a biomarker in HCM has a high degree of inter-reader variability and should be applied with caution as part of decision making for ICD insertion. Better standardization efforts in HCM recommendations by current governing societies are needed to improve clinical decision making in patients with HCM.

Prevalence, causes and predictors of cardiovascular hospitalization in patients with hypertrophic cardiomyopathy.

BACKGROUND: Despite numerous studies assessing the natural history of patients with hypertrophic cardiomyopathy (HCM), there is lack of data regarding the burden of hospitalization. Aim of this study was to describe prevalence, causes and predictors of cardiovascular hospitalization in patients with HCM. METHODS: We retrospectively included 253 patients with HCM undergoing first evaluation at our center. Enrolment criteria included cardiac magnetic resonance imaging (CMRI) at baseline and > 1-year follow-up. All hospital admissions were recorded during follow-up and adjudicated as acute vs elective and cardiovascular (CV) vs non-cardiovascular (non-CV). RESULTS: During 6.4 ± 4.0 years there were 187 hospitalizations in 92 patients (36%, at a rate of 5.7%/year). Most were CV-related (158/187,84.5%; 4.8%/year) while non-CV admissions were 29/187 (15.5%, 0.88%/year). There was a slight predominance of elective (n = 96, 58%, 2.8%/year) vs acute (n = 62, 41.8%, 2.0%/year) CV hospitalizations. Independent predictors of CV hospitalization were baseline symptoms (NYHA class II vs I: HR 2.06; 95% CI 1.24-3.43, NYHA III-IV vs I: HR 3.05; 95% CI 1.40-6.65, p = .004), indexed left atrial (LA) volume (HR 1.03; 95% CI 1.01-1.04, p < .001), and lower indexed right ventricular end-diastolic volume iRVEDV) at cardiac magnetic resonance (HR 0.99; 95% CI 0.97-0.99, p = .03). CONCLUSIONS: In little over 6 years, CV hospitalization was required in over one-in-three of our HCM patients, often unplanned and due to acute disease-related complications. Symptomatic status, larger LA volume and reduced iRVEDV at baseline were independently associated with CV admissions. Strategies aimed at preventing hospitalizations are an important target to reduce the burden of disease in HCM patients.

Sex-related differences in exercise performance and outcome of patients with hypertrophic cardiomyopathy.

AIMS: Exercise performance is known to predict outcome in hypertrophic cardiomyopathy (HCM), but whether sex-related differences exist is unresolved. We explored whether functional impairment, assessed by exercise echocardiography, has comparable predictive accuracy in females and males with HCM. METHODS: We retrospectively evaluated 292 HCM patients (46 ± 16 years, 72% males), consecutively referred for exercise echocardiography; 242 were followed for 5.9 ± 4.2 years. RESULTS: Peak exercise capacity was 6.5 ± 1.6 metabolic equivalents (METs). Sixty patients (21%) showed impaired exercise capacity (≤5 METs). Exercise performance was reduced in females, compared with males (5.6 ± 1.6 vs 6.9 ± 1.5 METs, p < 0.001; peak METs ≤ 5 in 40% vs 13%, p < 0.001), largely driven by a worse performance in women >50 years of age. At multivariable analysis, female sex was independently associated with impaired exercise capacity (odds ratio: 4.67; 95% confidence interval (CI): 1.83-11.90; p = 0.001). During follow-up, 24 patients (10%) met the primary endpoint (a combination of cardiac death, heart failure requiring hospitalization, sustained ventricular tachycardia, appropriate implantable cardioverter defibrillator discharge, resuscitated sudden cardiac death and cardioembolic stroke). Event-free survival was reduced in females (p = 0.035 vs males). Peak METs were inversely related to outcome in males (hazard ratio (HR) per unit increase: 0.57; 95% CI: 0.39-0.84; p = 0.004) but not in females (HR: 1.22; 95% CI: 0.66-2.24; p = 0.53). CONCLUSIONS: Female patients with HCM showed significant age-related impairment in functional capacity compared with males, particularly evident in post-menopausal age groups. While women were at greater risk of HCM-related complications and death, impaired exercise capacity predicted adverse outcome only in men. These findings suggest the need for sex-specific management strategies in HCM.