UNASSIGNED: Hypertrophic cardiomyopathy is a genetic heart condition occurring in up to 1 in 200 patients in the United States, many of whom are young and otherwise healthy. This condition puts those affected at increased risk for adverse cardiac outcomes, including sudden cardiac arrest and death, with particular concern for this to occur during exercise and other forms of exertion. Recent studies aimed at evaluating the risk of exercise in hypertrophic cardiomyopathy patients have suggested that moderate and even vigorous exercise may be safe for certain patients. Clinical guidelines are changing to reflect this recent information and to encourage a shared decision-making approach, which can allow more hypertrophic cardiomyopathy patients to participate in health-promoting exercise activities.

Apical hypertrophic cardiomyopathy (HCM) is a rare variant of HCM. A 43-year-old female with a past medical history significant for hypertension and kidney transplantation presented with recurrent syncopal episodes and dyspnea on exertion. Electrocardiogram showed characteristic diffuse giant T-waves inversion, and cardiac magnetic resonance showed HCM with circumferential apical thickening. This case highlights the rapid development of apical HCM and its challenging diagnostic characteristics.

Genetic hypertrophic cardiomyopathy (HCM) is classically caused by pathogenic/likely pathogenic variants in sarcomere genes (G+). Currently, HCM is diagnosed if there is unexplained left ventricular (LV) hypertrophy with LV wall thickness ≥15 mm in probands or ≥13 mm in at-risk relatives. Although LV hypertrophy is a key feature, this binary metric does not encompass the full constellation of phenotypic features, particularly in the subclinical stage of the disease. Subtle phenotypic manifestations can be identified in sarcomere variant carriers with normal LV wall thickness, before diagnosis with HCM (G+/LV hypertrophy-; subclinical HCM). We conducted a systematic review to summarize current knowledge about the phenotypic spectrum of subclinical HCM and factors influencing penetrance and expressivity. Although the mechanisms driving the development of LV hypertrophy are yet to be elucidated, activation of profibrotic pathways, impaired relaxation, abnormal Ca2+ signaling, altered myocardial energetics, and microvascular dysfunction have all been identified in subclinical HCM. Progression from subclinical to clinically overt HCM may be more likely if early phenotypic manifestations are present, including abnormal ECG, longer mitral valve leaflets, lower global E\' velocities on Doppler echocardiography, and higher serum N-terminal propeptide of B-type natriuretic peptide. Longitudinal studies of variant carriers are critically needed to improve our understanding of penetrance, characterize the transition to disease, identify risk predictors of phenotypic evolution, and guide the development of novel treatment strategies aimed at influencing disease trajectory.

UNASSIGNED: Sudden cardiac death in athletes is a rare occurrence, the most common cause being hypertrophic cardiomyopathy, which increases the risk of sustained ventricular tachycardia or ventricular fibrillation. Most of these young athletes are asymptomatic prior to the cardiac arrest. Several electrocardiogram criteria such as the European Society of Cardiology group 2 Criteria changes, Seattle Criteria, Refined Criteria, and most recently the 2017 International Criteria, have sought to improve the accuracy of identifying these at-risk athletes during pre-participation screening while minimising unnecessary investigations for the majority of athletes at low risk.We aimed to compare the above four criteria in our Singapore athlete population to identify which criterion performed the best in detecting cardiac abnormalities on echocardiography.
UNASSIGNED: Out of 1,515 athletes included in Changi General Hospital, Singapore registry between June 2007 and June 2014, the electrocardiograms of 270 athletes with further cardiac investigations were analysed. We compared the above four electrocardiographic criteria to evaluate which performed best for detecting cardiac abnormalities on echocardiography in our Southeast Asian athlete population.
UNASSIGNED: The European Society of Cardiology, Seattle, Refined and 2017 International Criteria had a sensitivity of 20%, 0%, 20% and 5%, respectively; a specificity of 64%, 93%, 84% and 97%, respectively; a positive predictive value of 4%, 0%, 9% and 11%, respectively; and a negative predictive value of 91%, 92%, 93% and 93%, respectively for detecting abnormalities on echocardiography.
UNASSIGNED: The latest 2017 International Criteria performed the best as it had the highest specificity and positive predictive value, joint highest negative predictive value, and lowest false positive rate.

UNASSIGNED: Despite the growing recognition that sex can affect the presentation and outcomes in hypertrophic cardiomyopathy (HCM), this relationship is understudied in Asians. Therefore, we aimed to explore sex differences in Asian patients with HCM.
UNASSIGNED: A total of 295 consecutive patients diagnosed with HCM were recruited from a tertiary cardiology centre from 2010 to 2017 over a mean of 3.9±2.7 years. We evaluated the effects of sex on the outcomes of HCM in Asian patients.
UNASSIGNED: HCM patients were more commonly men (72%). Women were older and had more comorbidities, including hypertension and atrial fibrillation. On transthoracic echocardiography, the indexed left ventricular end-systolic and end-diastolic volumes were similar, but more women had more-than-moderate mitral regurgitation and had a smaller left ventricular outflow tract (LVOT). Women more commonly had findings of obstructive physiology with significant LVOT obstruction, defined as >30 mmHg at rest. The use of implantable cardioverter defibrillators was similar across sexes. On multivariable analysis, women were found to be more likely to develop progressive heart failure requiring admission (hazard ratio [HR] 2.10, 95% confidence interval [CI] 1.05-4.71, P=0.021) but had a lower rate of all-cause mortality (HR 0.36, 95% CI 0.19-0.70, P=0.003).
UNASSIGNED: Women diagnosed with HCM were older, had more comorbidities and were more likely to develop heart failure while men had a higher risk of all-cause mortality.

BACKGROUND: Previous studies have shown the importance of energy deficiency and malfunctioning mitochondria in the pathophysiology of hypertrophic cardiomyopathy (HCM). There has been a little research into the relationship between plasma free fatty acids (FFA), one of the heart\'s main energy sources, and HCM. We evaluated its clinical importance in HCM to see if there was a link between plasma FFA metabolism and HCM.
METHODS: In a single-center retrospective observational study, we investigated 420 HCM patients diagnosed at Beijing Anzhen Hospital between January 1, 2018, and December 31, 2022. Meanwhile, 1372 individuals without HCM (non-HCM) were recruited. 391 non-HCM patients were chosen as controls via a propensity score matching (PSM) study with a 1:1 ratio.
RESULTS: FFA in HCM patients showed statistically significant correlations with creatinine (r = 0.115, p = 0.023), estimated GFR (r=-0.130, p = 0.010), BNP (r = 0.152, p = 0.007), LVEF (r=-0.227, p < 0.001), LVFS (r=-0.160, p = 0.002), and LAD (r = 0.112, p = 0.028). Higher FFA levels were found in HCM patients who had atrial fibrillation and NYHY functional classes III or IV (p = 0.015 and p = 0.022, respectively). In HCM patients, multiple linear regression analysis revealed that BNP and LVEF had independent relationships with increasing FFA (Standardized = 0.139, p = 0.013 and =-0.196, p < 0.001, respectively).
CONCLUSIONS: Among HCM patients, the plasma FFA concentration was lower, and those with AF and NYHY functional class III or IV had higher FFA levels, and LVEF and BNP were independently associated with increasing FFA. The findings of the study should help inspire future efforts to better understand how energy deficiency contributes to hypertrophic cardiomyopathy (HCM) development.

BACKGROUND: In patients with hypertrophic cardiomyopathy (HCM), impaired augmentation of stroke volume and diastolic dysfunction contribute to exercise intolerance. Systolic-diastolic (S-D) coupling characterizes how systolic contraction of the left ventricle (LV) primes efficient elastic recoil during early diastole. Impaired S-D coupling may contribute to the impaired cardiac response to exercise in patients with HCM.
METHODS: Patients with HCM (n = 25, age = 47 ± 9 years) and healthy adults (n = 115, age = 49 ± 10 years) underwent a cardiopulmonary exercise testing (CPET) and echocardiogram. S-D coupling was defined as the ratio of LV longitudinal excursion of the mitral annulus during early diastole (EDexc) and systole (Sexc) and compared between groups. Peak oxygen uptake (peak V̇O2) (Douglas bags), cardiac index (C2H2 rebreathe), and stroke volume index (SVi) were assessed during CPET. Linear regression was performed between S-D coupling and peak V̇O2, peak cardiac index, and peak SVi.
RESULTS: S-D coupling was lower in HCM (Controls: 0.63 ± 0.08, HCM: 0.56 ± 0.10, p < 0.001). Peak V̇O2 and stroke volume reserve were lower in patients with HCM (Peak VO2 Controls: 28.5 ± 5.5, HCM: 23.7 ± 7.2 mL/kg/min, p < 0.001, SV reserve: Controls 39 ± 16, HCM 30 ± 18 mL, p = 0.008). In patients with HCM, S-D coupling was associated with peak V̇O2 (r = 0.47, p = 0.018), peak cardiac index (r = 0.60, p = 0.002), and peak SVi (r = 0.63, p < 0.001).
CONCLUSIONS: Systolic-diastolic coupling was impaired in patients with HCM and was associated with fitness and the cardiac response to exercise. Inefficient S-D coupling may link insufficient stroke volume generation, diastolic dysfunction, and exercise intolerance in HCM.

Hypertrophic cardiomyopathy (HCM) is a heart condition characterized by cellular and metabolic dysfunction, with mitochondrial dysfunction playing a crucial role. Although the direct relationship between genetic mutations and mitochondrial dysfunction remains unclear, targeting mitochondrial dysfunction presents promising opportunities for treatment, as there are currently no effective treatments available for HCM. This review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews guidelines. Searches were conducted in databases such as PubMed, Embase, and Scopus up to September 2023 using \"MESH terms\". Bibliographic references from pertinent articles were also included. Hypertrophic cardiomyopathy (HCM) is influenced by ionic homeostasis, cardiac tissue remodeling, metabolic balance, genetic mutations, reactive oxygen species regulation, and mitochondrial dysfunction. The latter is a common factor regardless of the cause and is linked to intracellular calcium handling, energetic and oxidative stress, and HCM-induced hypertrophy. Hypertrophic cardiomyopathy treatments focus on symptom management and complication prevention. Targeted therapeutic approaches, such as improving mitochondrial bioenergetics, are being explored. This includes coenzyme Q and elamipretide therapies and metabolic strategies like therapeutic ketosis. Understanding the biomolecular, genetic, and mitochondrial mechanisms underlying HCM is crucial for developing new therapeutic modalities.

肥厚型心肌病是常见的遗传性心脏疾病，也是引起年轻人心原性猝死的主要原因之一，经过谨慎评估后植入心律转复除颤器能够有效减少猝死发生。近年来，随着肥厚型心肌病新的猝死风险指标的不断出现，对猝死的评估也更加具体和精确，但是鉴于猝死发生的不确定性和低概率性，目前尚没有统一而全面的猝死风险评估标准。该文结合美国及欧洲最新指南，对肥厚型心肌病传统和新兴的风险预测因子进行综述，探讨进行室间隔切除术的梗阻性肥厚型心肌病患者的术后猝死风险，以期为心原性猝死的风险评估及预防提供参考。.

肥厚型心肌病是常见的遗传性心肌病，具有高度异质性和高猝死率的特点，是儿童心原性猝死的最常见原因。该文对儿童肥厚型心肌病的药物及侵入性治疗、心律失常管理、特殊类型肥厚型心肌病治疗等方面的研究进展进行综述，以期为临床治疗及进一步研究提供参考。.