Prognosis Of Hypertrophic Cardiomyopathy Research Articles

Evaluation of the prognostic value of papillary muscle-free strain in patients with hypertrophic cardiomyopathy.

The prognosis of hypertrophic cardiomyopathy (HCM) varies from mild disease with a normal life expectancy to heart failure and sudden cardiac death (SCD). The identification of patients who are at high risk for SCD remains challenging. In this study, we evaluated the prognostic value of papillary muscle-free strain in HCM patients. Seventy-nine patients with a diagnosis of HCM were included in this study. Patients were divided into low/intermediate-risk (n=57) and high-risk (n=22) groups. Two-dimensional (2-D) echocardiography and strain imaging were performed for each patient. The mean age of the study population was 53.85±15.88 years; 47 (59.5%) of them were male. During a mean follow-up duration of 74.45±17.03 months, 12 patients died. A comparison of the low-intermediate and high-SCD risk groups revealed that patients in the high-SCD risk group had greater maximal wall thickness, interventricular septum thickness, posterior wall thickness, and left ventricular mass index (LVMI) and lower (less negative) global longitudinal, anterolateral papillary muscle (ALPM) and posteromedial papillary muscle (PMPM) free strain. Additionally, a history of syncope and ICD implantation were found to be more common in patients with high SCD risk scores. The SCD risk score was positively correlated with the global longitudinal strain, ALPM-free strain, and PMPM-free strain (r=.528, r=.658, and r=.600, respectively; p<.001 for all). Our results showed that the LVMI, presence of syncope, global longitudinal strain, and ALPM-free strain were predictors of death. Decreased papillary muscle-free strain values might have prognostic value in patients with HCM.

Cardiac Magnetic Resonance Imaging in Hypertrophic Cardiomyopathy: What a Cardiologist Should Know

Abstract Hypertrophic cardiomyopathy (HCM) affects 1 in 200–500 of the general population, with about 10%–20% identified clinically. The primary goal of imaging for a cardiologist is to provide an accurate diagnosis and add prognostic value. Multiplanar electrocardiogram-gated cardiac magnetic resonance (CMR) imaging can evaluate all phases of the cardiac cycle. CMR excels in the accurate and reproducible evaluation of cardiac morphology, particularly in determining wall thickness and the distribution of hypertrophy. It can also assess the mitral valvular apparatus. Functional evaluation includes assessing contractility, accurate ejection fraction quantification, and visualizing and quantifying dynamic flow, particularly in the subaortic region. CMR strain imaging with feature tracking software evaluates segmental contractility. Late gadolinium enhancement (delayed enhancement), T1, and extracellular volume mapping add to the prognostic ability of CMR magnetic resonance imaging in predicting outcome by evaluating the myocardial fibrosis. CMR also adds value by evaluating the left atrium and right ventricle. A combination of the above helps accurately differentiate between phenotypes of HCM, suggest genetic forms of HCM, and monitor patients after treatment to track disease progression or changes. This review aims to describe the multiparametric strengths of CMR in the diagnosis and prognosis of HCM.

Association of Impaired Left Ventricular Mitral Filling from 4D Flow Cardiac MRI and Prognosis of Hypertrophic Cardiomyopathy.

Purpose To investigate whether the peak early filling rate normalized to the filling volume (PEFR/FV) estimated from four-dimensional (4D) flow cardiac MRI may be used to assess impaired left ventricular (LV) filling and predict clinical outcomes in individuals with hypertrophic cardiomyopathy (HCM). Materials and Methods Cardiac MRI with a 4D flow sequence and late gadolinium enhancement (LGE), as well as echocardiography, was performed in 88 individuals: 44 participants with HCM from a French prospective registry (ClinicalTrials.gov; NCT01091480) and 44 healthy volunteers matched for age and sex. In participants with HCM, a composite primary end point was assessed at follow-up, including unexplained syncope, new-onset atrial fibrillation, hospitalization for congestive heart failure, ischemic stroke, sustained ventricular arrhythmia, septal reduction therapy, and cardiac death. A Cox proportional hazard model was used to analyze associations with the primary end point. Results PEFR/FV was significantly lower in the HCM group (mean age, 51.8 years ± 18.5 [SD]; 29 male participants) compared with healthy volunteers (mean, 3.35 sec-1 ± 0.99 [0.90-5.20] vs 4.42 sec-1 ± 1.68 [2.74-11.86]; P < .001) and correlated with both B-type natriuretic peptide (BNP) level (r = -0.31; P < .001) and the ratio of pulsed Doppler early transmitral inflow to Doppler tissue imaging annulus velocities (E/E'; r = -0.54; P < .001). At a median follow-up of 2.3 years (IQR, 1.7-3.3 years), the primary end point occurred in 14 (32%) participants. A PEFR/FV of 2.61 sec-1 or less was significantly associated with occurrence of the primary end point (hazard ratio, 9.46 [95% CI: 2.61, 45.17; P < .001] to 15.21 [95% CI: 3.51, 80.22; P < .001]), independently of age, BNP level, E/E', LGE extent, and LV and left atrial strain according to successive bivariate models. Conclusion In HCM, LV filling evaluated with 4D flow cardiac MRI correlated with Doppler and biologic indexes of diastolic dysfunction and predicted clinical outcomes. Keywords: Diastolic Function, Left Ventricular Filling, Hypertrophic Cardiomyopathy, Cardiac MRI, 4D Flow Sequence Clinical trial registration no. NCT01091480 Supplemental material is available for this article. © RSNA, 2024.

Clinical characteristics and prognosis of patients with hypertrophic cardiomyopathy and heart failure with preserved ejection fraction.

Whether heart failure with preserved ejection fraction (HFpEF) is associated with an increased risk of developing systolic dysfunction and a poor prognosis in hypertrophic cardiomyopathy (HCM) patients is unknown. We aimed to assess risk factors for the development of end-stage (ES) heart failure (HF) (ejection fraction < 50%) and compare the prognosis of different HF phenotypes. This retrospective study was conducted on patients with HCM in China between January 2009 and February 2023. Patients were stratified into three different groups: HCM-non-HF, HCM-HFpEF and HCM-heart failure with reduced ejection fraction (HCM-HFrEF). The primary outcome was a composite of major adverse cardiac events (MACEs), including all-cause deaths, HF hospitalization, sudden cardiac death and ventricular tachycardia. Of 3,620 HCM patients enrolled, 1,553 (42.9%) had non-HF, 1,666 (46.0%) had HFpEF, and 579 patients (11.1%) had HFrEF at baseline. During the median follow-up period of 4.0 years (IQR 1.4-9.4 years), patients with HCM-HFpEF exhibited a higher incidence of ES-HF than those with HCM-non-HF (12.4% vs. 2.7%, P < 0.001). HFpEF was an independent risk factor for ES-HF development (HR 3.84, 2.54-5.80, P < 0.001). MACEs occurred in 26.9% with a higher incidence in HCM-HFpEF than HCM-non-HF (36.6% vs 12.2%, P < 0.001). HFpEF was an independent predictor of MACEs (HR 2.13, 1.75-2.59, P < 0.001). HFpEF is common in HCM. Compared to non-HF, it increases the risk of LVEF decline and poor prognosis. It may aid in risk stratification and need close echocardiography follow-up.

Profiling cardiomyocytes at single cell resolution reveals COX7B could be a potential target for attenuating heart failure in cardiac hypertrophy

Cardiac hypertrophy can develop to end-stage heart failure (HF), which inevitably leading to heart transplantation or death. Preserving cardiac function in cardiomyocytes (CMs) is essential for improving prognosis in hypertrophic cardiomyopathy (HCM) patients. Therefore, understanding transcriptomic heterogeneity of CMs in HCM would be indispensable to aid potential therapeutic targets investigation. We isolated primary CM from HCM patients who had extended septal myectomy, and obtained transcriptomes in 338 human primary CM with single-cell tagged reverse transcription (STRT-seq) approach. Our results revealed that CMs could be categorized into three subsets in nonfailing HCM heart: high energy synthesis cluster, high cellular metabolism cluster and intermediate cluster. The expression of electron transport chain (ETC) was up-regulated in larger-sized CMs from high energy synthesis cluster. Of note, we found the expression of Cytochrome c oxidase subunit 7B (COX7B), a subunit of Complex IV in ETC had trends of positively correlation with CMs size. Further, by assessing COX7B expression in HCM patients, we speculated that COX7B was compensatory up-regulated at early-stage but down-regulated in failing HCM heart. To test the hypothesis that COX7B might participate both in hypertrophy and HF progression, we used adeno associated virus 9 (AAV9) to mediate the expression of Cox7b in pressure overload-induced mice. Mice in vivo data supported that knockdown of Cox7b would accelerate HF and Cox7b overexpression could restore partial cardiac function in hypertrophy. Our result highlights targeting COX7B and preserving energy synthesis in hypertrophic CMs could be a promising translational direction for HF therapeutic strategy.

Association between left atrial myopathy and sarcomere mutation in patients with hypertrophic cardiomyopathy: insights into left atrial strain by MRI feature tracking.

Left atrial (LA) myopathy, characterized by LA enlargement and mechanical dysfunction, is associated with worse prognosis in hypertrophic cardiomyopathy (HCM) while the impact of sarcomere mutation on LA myopathy remains unclear. We aimed to assess the association between LA myopathy and sarcomere mutation and to explore the incremental utility of LA strain in mutation prediction. A total of 105 consecutive HCM patients (mean age 47.8 ± 11.9years, 71% male) who underwent HCM-related gene screening and cardiac MRI were retrospectively enrolled. LA volume, ejection fraction and strain indices in reservoir, conduit, and booster-pump phases were investigated respectively. Fifty mutation-positive patients showed higher LA maximal volume index (59.4 ± 28.2 vs 43.8 ± 18.1mL/m2, p = 0.001), lower reservoir (21.3 ± 7.9 vs 26.2 ± 6.6%, p < 0.001), and booster-pump strain (12.1 ± 5.4 vs 17.1 ± 5.0%, p < 0.001) but similar conduit strain (9.2 ± 4.5 vs 9.1 ± 4.5%, p = 0.909) compared with mutation-negative patients. In multivariate logistic regression, LA booster-pump strain was associated with sarcomere mutation (odds ratio = 0.86, 95% confidence interval: 0.77-0.96, p = 0.010) independent of maximal wall thickness, late gadolinium enhancement, and LA volume. Furthermore, LA booster-pump strain showed incremental value for mutation prediction added to Mayo II score (AUC 0.798 vs 0.709, p = 0.024). In HCM, mutation-positive patients suffered worse LA enlargement and worse reservoir and booster-pump functions. LA booster-pump strain was a strong factor for sarcomere mutation prediction added to Mayo II score. The independent association between sarcomere mutation and left atrial mechanical dysfunction provide new insights into the pathogenesis of atrial myopathy and is helpful to understand the adverse prognosis regarding atrial fibrillation and stroke in mutation-positive patients. • In patients with hypertrophic cardiomyopathy, left atrial (LA) reservoir and booster-pump function, but not conduit function, were significantly impaired in mutation-positive patients compared with mutation-negative patients. • LA booster-pump strain measured by MRI-derived feature tracking is feasible to predict sarcomere mutation with high incremental value added to Mayo II score.

The Importance of Left Ventricular Outflow Tract and Mid-Ventricular Gradients in Stress Echocardiography: A Narrative Review.

This review aims to serve as a guide for clinical practice and to appraise the current knowledge on exercise stress echocardiography in the evaluation of intraventricular obstruction in HCM, in patients with cardiac syndrome X, in athletes with symptoms related to exercise, and in patients with normal left ventricular systolic function and exercise-related unexplained tiredness. The appearance of intraventricular obstruction while exercising is considered rare, and it usually occurs in patients with hypertrophy of the left ventricle. The occurrence of intraventricular obstruction when exercising has been evidenced in patients with hypertrophic cardiomyopathy, athletes, patients with cardiac syndrome X, patients with syncope or dizziness related to exercise, and patients with dyspnea and preserved ejection fraction. The clinical significance of this observation and the exercise modality that is most likely to trigger intraventricular obstruction remains unknown. Supine exercise and lying supine after exercise are less technically demanding, but they are also less physiologically demanding than upright exercise. Importantly, in everyday life, human beings generally do not become supine after exercise, as takes place in post-exercise treadmill stress echocardiograms in most echocardiography labs. The presence of induced intraventricular obstruction might be considered when patients have exercise-related symptoms that are not understood, and to assess prognosis in hypertrophic cardiomyopathy.

Identifying Obstructive Hypertrophic Cardiomyopathy from Nonobstructive Hypertrophic Cardiomyopathy: Development and Validation of a Model Based on Electrocardiogram Features.

The clinical presentation and prognosis of hypertrophic cardiomyopathy (HCM) are heterogeneous between nonobstructive HCM (HNCM) and obstructive HCM (HOCM). Electrocardiography (ECG) has been used as a screening tool for HCM. However, it is still unclear whether the features presented on ECG could be used for the initial classification of HOCM and HNCM. We aimed to develop a pragmatic model based on common 12-lead ECG features for the initial identification of HOCM/HNCM. Between April 1st and September 30th, 2020, 172 consecutive HCM patients from the International Cooperation Center for Hypertrophic Cardiomyopathy of Xijing Hospital were prospectively included in the training cohort. Between January 4th and February 30th, 2021, an additional 62 HCM patients were prospectively included in the temporal internal validation cohort. External validation was performed using retrospectively collected ECG data with definite classification (390 HOCM and 499 HNCM ECG samples) from January 1st, 2010 to March 31st, 2020. Multivariable backward logistic regression (LR) was used to develop the prediction model. The discrimination performance, calibration and clinical utility of the model were evaluated. Of all 30 acquired ECG parameters, 10 variables were significantly different between HOCM and HNCM (all P < 0.05). The P wave interval and SV1 were selected to construct the model, which had a clearly useful C-statistic of 0.805 (0.697, 0.914) in the temporal validation cohort and 0.776 (0.746, 0.806) in the external validation cohort for differentiating HOCM from HNCM. The calibration plot, decision curve analysis, and clinical impact curve indicated that the model had good fitness and clinical utility. The pragmatic model constructed by the P wave interval and SV1 had a clearly useful ability to discriminate HOCM from HNCM. The model might potentially serve as an initial classification of HCM before referring patients to dedicated centers and specialists. What are the novel findings of this work? Evident differences exist in the ECG presentations between HOCM and HNCM.To the best of our knowledge, this study is the first piece of evidence to quantify the difference in the ECG presentations between HOCM and HNCM.Based on routine 12-lead ECG data, a probabilistic model was generated that might assist in the initial classification of HCM patients.

Is There a Sex Difference in the Prognosis of Hypertrophic Cardiomyopathy? A Systematic Review and Meta-Analysis.

Background It is still unclear whether there is a sex difference in the prognosis of patients with hypertrophic cardiomyopathy (HCM). Therefore, we performed a meta-analysis to elucidate the association between sex and adverse outcomes in patients with HCM. Methods and Results The PubMed, Cochrane Library, and Embase databases were used to search for studies on sex differences in prognosis in patients with HCM up to August 17, 2021. Summary effect sizes were calculated using a random effects model. The protocol was registered in PROSPERO (International prospective register of systematic reviews) (registration number- CRD42021262053). A total of 27 cohorts involving 42 365 patients with HCM were included. Compared with male subjects, female subjects had a higher age at onset (mean difference=5.61 [95% CI, 4.03-7.19]), a higher left ventricular ejection fraction (standard mean difference=0.09 [95% CI, 0.02-0.15]) and a higher left ventricular outflow tract gradient (standard mean difference=0.23 [95% CI, 0.18-0.29]). The results showed that compared with male subjects with HCM, female subjects had higher risks of HCM-related events (risk ratio [RR]=1.61 [95% CI, 1.33-1.94], I2=49%), major cardiovascular events (RR=3.59 [95% CI, 2.26-5.71], I2=0%), HCM-related death (RR=1.57 [95% CI, 1.34-1.82], I2=0%), cardiovascular death (RR=1.55 [95% CI, 1.05-2.28], I2=58%), noncardiovascular death (RR=1.77 [95% CI, 1.46-2.13], I2=0%) and all-cause mortality (RR=1.43 [95% CI, 1.09-1.87], I2=95%), but not atrial fibrillation (RR=1.13 [95% CI, 0.95-1.35], I2=5%), ventricular arrhythmia (RR=0.88 [95% CI, 0.71-1.10], I2=0%), sudden cardiac death (RR=1.04 [95% CI, 0.75-1.42], I2=38%) or composite end point (RR=1.24 [95% CI, 0.96-1.60], I2=85%). Conclusions Based on current evidence, our results show significant sex-specific differences in the prognosis of HCM. Future guidelines may emphasize the use of a sex-specific risk assessment for the diagnosis and management of HCM.

Assessing the relationship between monocyte-to-HDL cholesterol ratio and mortality in patients with hypertrophic cardiomyopathy

ObjectiveA new inflammatory marker, namely monocyte-to-high-density lipoprotein cholesterol ratio (MHR), has emerged as a useful indicator for adverse outcomes in several cardiovascular diseases; however, the relationship between MHR and the prognosis of hypertrophic cardiomyopathy (HCM) remains to be evaluated. We examined the relationship between MHR and all-cause mortality (ACM) in Chinese adult patients with HCM. MethodsWe retrospectively performed clinical evaluation in 305 patients with HCM (median age: 52.0 years, male: 54.10%). ResultsDuring a median follow-up of 4.9 years, ACM occurred in 57 (18.7%) patients. Based on the tertiles of baseline MHR, ACM increased with higher tertile. With tertile 1 as reference, adjusted ACM hazard ratios (HRs) were 2.68 for tertile 2 (95% confidence interval [CI]: 1.18-6.11, p = 0.019) and 4.85 for tertile 3 (95% CI: 2.16-10.89, p < 0.001). Stratified analysis and E-value analysis suggested the robustness of the above-mentioned results. Furthermore, adjusted smooth curve fitting exhibited a non-linear relationship between MHR and ACM (inflection point: 0.5), and the risk of ACM increased significantly with higher MHR only the value below the inflection point (HR: 4.37 per one standard deviation, 95% CI: 1.81-10.6, p = 0.001). Finally, sensitivity analysis was similar to the main findings. ConclusionIn Chinese adult patients with HCM, higher MHR is a strong independent predictor of ACM, and a non-linear relationship is also observed between MHR and ACM.

Contribution of artificial intelligence and left atrial strain in the prediction of sudden cardiac death in hypertrophic cardiomyopathy. Results of a multicentric cohort

Sudden cardiac death (SCD) remains a serious outcome in hypertrophic cardiomyopathy (HCM), with an estimated incidence of 1%/year. Its risk prediction stays challenging for clinicians. Implantation of cardioverter-defibrillator is recommended with a strong level of evidence when the HCM risk score is over 6%. However, the ESC HCM risk score is criticized for its moderate diagnostic performance (C-index 0,70), and its low sensibility. Recent studies suggest that low PALS (peak atrial longitudinal strain) is associated with poor prognosis in HCM. Artificial intelligence, wich is experiencing an unprecedented boom, may be an interesting tool in association to left atrial strain in Prognostication. This preliminar study aimed to evaluate the value of the left atrial strain coupled with artificial inteligence algorythm in the prediction of suddent cardiac death in hypertrophic cardiomyopathy. This restrospective multi-center cohort (Marseille la Timone, Bordeaux and Rennes) included 431 patients with sarcomeric HCM from 2007 to 2018. The average follow-up time was 57 months. The primary endpoint was all cause death, ventricular arythmias, recovered SCD and internal electric shock. Analyses were entrusted to the LIS laboratory specialized in Computer Science at Aix-Marseille University. Sixty-six percent of men composed the cohort with a mean age of 52 ± 16 yo. Sarcomeric mutations were found in 52% of them, the mean left ventricular ejection fraction was 63 ± 16, 23% had significant ventricular obstruction. The mean PALS was 25 ± 12%. In the multivariate analysis, PALS 4 chamber, left ventricular global longitudinal strain and syncope were associated with the primary endpoint, (respectivly HR 2,48 IC95% [1,09–5,63]; P 0,030; HR 1,13 IC95% [1,03–1,25]; P 0,012; HR 0,95 IC95% [0,92–0,99]; P: 0.023). The random Forrest algorithm was able to successfully classify the patient (occurrence of primary endpoint or not) in 92,2% of the cases. Left atrial strain coupled with the Random Forrest algorithm could offer an interesting implementative value for the prediction of sudden cardiac death in hypertrophic cardiomyopathy. Further analysis are required to define its sensibility and specificity.

Recent research on childhood hypertrophic cardiomyopathy caused by MYH7 gene mutations

Hypertrophic cardiomyopathy (HCM) is the most common monogenic inherited myocardial disease in children, and mutations in sarcomere genes (such as MYH7 and MYBPC3) are the most common genetic etiology of HCM, among which mutations in the MYH7 gene are the most common and account for 30%-50%. MYH7 gene mutations have the characteristics of being affected by environmental factors, coexisting with multiple genetic variations, and age-dependent penetrance, which leads to different or overlapping clinical phenotypes in children, including various cardiomyopathies and skeletal myopathies. At present, the pathogenesis, course, and prognosis of HCM caused by MYH7 gene mutations in children remain unclear. This article summarizes the possible pathogenesis, clinical phenotype, and treatment of HCM caused by MYH7 gene mutations, in order to facilitate the accurate prognostic evaluation and individualized management and treatment of the children with this disorder.

The role of cardiac catheterization in solving the issue of surgical treatment of symptomatic hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an underdiagnosed genetic heart disease with a prevalence of 0.2–0.5 %. Although the prognosis of HCM is relatively favorable, the annual overall mortality is about 0.7 %. The most common complication of HCM is obstruction of the left ventricular outflow tract (LVOT). Careful diagnosis and timely identification of high-risk patients by confirming the presence and degree of obstruction of the left ventricular outflow tract may reduce morbidity and mortality due to timely and correctly selected treatment. One-third of patients with HCM have echocardiographically confirmed LVOT obstruction at rest, and another third may have LVOT obstruction with provocation. Our clinical case demonstrates the presence of a small group of patients with HCM, whose LVOT obstruction is underestimated by transthoracic echocardiography (TTE) neither at rest nor when using provocative tests (Valsalva tests, exercise), and its hemodynamic significance is revealed only with invasive hemodynamic catheterization of the heart. Below, we illustrate the utility of hemodynamic catheterization as an adjunctive tool to echocardiography to help establish the presence, magnitude, and location of obstruction in patients with HCM in the absence of such data on TTE. In case of a high degree of suspicion that LVOT obstruction is responsible for refractory symptoms, catheterization can establish the presence of a hemodynamically significant LVOT gradient and, accordingly, without deviating from clinical recommendations, to carry out optimal surgical treatment, in our case – septal alcohol ablation with subsequent elimination of symptoms and restoration of the patient’s endurance to physical exertion.

Potential of non-contrast stress T1 mapping for the assessment of myocardial injury in hypertrophic cardiomyopathy

BackgroundIschemia of the hypertrophied myocardium due to microvascular dysfunction is related to a worse prognosis in hypertrophic cardiomyopathy (HCM). Stress and rest T1 mapping without contrast agents can be used to assess myocardial blood flow. Herein, we evaluated the potential of non-contrast stress T1 mapping in assessing myocardial injury in patients with HCM. MethodsForty-five consecutive subjects (31 HCM patients and 14 control subjects) underwent cardiac magnetic resonance (CMR) at 3T, including cine imaging, T1 mapping at rest and during adenosine triphosphate (ATP) stress, late gadolinium enhancement (LGE), and phase-contrast (PC) cine imaging of coronary sinus flow at rest and during stress to assess coronary flow reserve (CFR). PC cine imaging was performed on 25 subjects (17 patients with HCM and 8 control subjects). Native T1 values at rest and during stress were measured using the 16-segment model, and T1 reactivity was defined as the change in T1 values from rest to stress. ResultsATP stress induced a significant increase in native T1 values in both the HCM and control groups (HCM: p < 0.001, control: p = 0.002). T1 reactivity in the HCM group was significantly lower than that in the control group (4.2 ± 0.3% vs. 5.6 ± 0.5%, p = 0.044). On univariate analysis, T1 reactivity correlated with native T1 values at rest, left ventricular mass index, and CFR. Multiple linear regression analysis demonstrated that only CFR was independently correlated with T1 reactivity (β = 0.449; 95% confidence interval, 0.048–0.932; p = 0.032). Furthermore, segmental analysis showed decreased T1 reactivity in the hypertrophied myocardium and the non-hypertrophied myocardium with LGE in the HCM group. ConclusionsT1 reactivity was lower in the hypertrophied myocardium and LGE-positive myocardium compared to non-injured myocardium. Non-contrast stress T1 mapping is a promising CMR method for assessing myocardial injury in patients with HCM.Trial registration Retrospectively registered.

Prognosis of hypertrophic cardiomyopathy in Japanese patients with an implantable cardioverter defibrillator -focus on apical hypertrophic cardiomyopathy

Abstract Background Patients with hypertrophic cardiomyopathy (HCM) are at high risk of lethal arrhythmias, and implantable cardioverter defibrillators (ICD) are widely used for prevention of sudden cardiac death (SCD). Apical HCM is a phenotype variant of HCM, with hypertrophy predominantly affecting apex, that was initially described 30 years ago. Apical HCM patients may have different clinical prognosis compared with other subsets of HCM. In previous studies, apical HCM patients seem to have a more benign prognosis than other types of HCM. However, little is known about the long-term outcomes of apical HCM patients and there are many unclear points. Moreover, there are few reports about the clinical prognosis in apical HCM patients with an ICD. Objective The aim of this study is to identify the difference between the prognosis of apical and the other types of HCM patients with an ICD. Methods We retrospectively analyzed the database of our ICD clinic. All subjects underwent ICD implantation between October 2006 and September 2018. We classified HCM patients into LV outflow tract obstruction (LVOTO) and midventricular obstruction (MVO), apical HCM and other non-obstructive types. We divided all the patients into apical and other types of HCM, and examined their background, incidence of appropriate ICD therapies, hospitalization for heart failure, electrical storm and death. Results A total of consecutive 64 Japanese HCM patients with an ICD (follow-up period, 86±24 months; age, 65±14 years; male sex, 83%; left ventricular ejection fraction, 56±14%; LV max wall-thickness, 19±7mm; LV apical aneurysm, 9.4%; 5-year risk of SCD, 4.4±2.1) were enrolled in this study. We classified them into 14 apical HCM and 50 other types of HCM patients. The clinical characteristics and major clinical events of these patients are shown in the Table 1. During the follow-up periods, there were no significant differences in the incidence of electrical storm, hospitalization for heart failure and death between the 2 groups (p=0.11; p=0.60; p=0.39). Appropriate ICD therapies occurred in 6 of 14 (43%) patients with apical HCM and 5 of 50 (10%) patients with other types of HCM (p=0.010). The risk factors of patients with apical HCM patients are shown in Table 2. Conclusions Appropriate ICD therapy was more prevalent in patients with apical HCM, compared to patients with other types of HCM. Aggressive intervention such as catheter ablation for ventricular tachycardia and ventricular fibrillation may be considered in patients with apical HCM and higher score of 5-year risk of SCD. Further studies are needed to clarify the manifestations and long-term outcome of apical HCM patients. Funding Acknowledgement Type of funding sources: None.

Could echocardiographic left atrial characterization have additive value for detecting risks of atrial arrhythmias and stroke in patients with hypertrophic cardiomyopathy?

Abstract Background Atrial arrhythmia (AA) is considered a turning point for prognosis in hypertrophic cardiomyopathy (HCM) patients. Prediction of AA and associated stroke risk in patients with HCM is an important clinical challenge as these events can occur in young subjects and significantly impact their quality of life. (1) (2) Purpose We sought to assess whether an echocardiographic evaluation focused on the left atrial (LA) characterization could estimate the occurrence of AA and stroke in HCM patients. Methods 216 HCM-patients (52±16 years old) were enrolled between 2016 and 2019. All patients underwent transthoracic echocardiography for the evaluation of left atrial volume (LAV), left ventricular global longitudinal strain (LV-GLS), peak left atrial strain (PLAS) and peak atrial contraction strain (PACS) by speckle-tracking imaging. A composite endpoint was defined as a history of AA and/or a history of stroke or peripheral embolism and/or occurrence of AA. Results The patients were followed for 2.9 years. Among the 216 patients, 78 (36%) met the composite endpoint. These patients were older (50.3±16.7 vs. 57.1±14.4 years, p=0.0035), had a higher prevalence of arterial hypertension (42.3% vs. 62.3%; p=0.005) and had higher NT-proBNP levels. LAV (37.2±15.7 vs. 47±20 ml/m2, p=0.0001) was significantly higher in patients who met the composite endpoint, whereas PLAS and PACS were significantly impaired (26.6±9.12 vs. 19.3±9.54%; p&amp;lt;0.0001 and 13.1±6.3% vs. 8.8±6.5%; p&amp;lt;0.0001, respectively). After adjustment, PLAS and PACS remained independently associated with events with an odds ratio (OR) of 0.42 for PLAS (95% CI, [0.29–0.61]; p&amp;lt;0.0001). Stroke occurred in 67% of the patients without any clinical AA. PLAS with a cut-off of under 15.5% provided event detection with 91% specificity and demonstrated a predictive value for new-onset of AA. Although there was a high correlation between PLAS and LV-GLS, LV-GLS was not associated with the events. Conclusion The impairment of LA function assessed by 2D speckle-tracking echocardiography was strongly associated with AA and the risk of stroke, even in patients without any documented AA. Its value for guiding the management of HCM-patients requires further investigation. Funding Acknowledgement Type of funding sources: None.

Contemporary Diagnosis and Management of Hypertrophic Cardiomyopathy: The Role of Echocardiography and Multimodality Imaging.

Hypertrophic cardiomyopathy (HCM) is an underdiagnosed genetic heart disease with an estimated prevalence of 0.2–0.5%. Although the prognosis of HCM is relatively good, with an annual general mortality of ~0.7%, some patients have an increased risk of sudden death, or of developing severe heart failure requiring heart transplantation or left ventricular (LV) assist device therapy. Therefore, earlier diagnosis and proper identification of high-risk patients may reduce disease-related morbidity/mortality by promoting timely treatment. Echocardiography is the primary imaging modality for patients with suspected HCM; it plays central roles in differential diagnosis from other causes of LV hypertrophy and in evaluating morphology, hemodynamic disturbances, LV function, and associated valvular disease. Echocardiography is also an essential tool for the continuous clinical management of patients with confirmed HCM. Other imaging modalities, such as cardiac computed tomography (CT) and cardiac magnetic resonance imaging (MRI), can supplement echocardiography in identifying high-risk as well as milder HCM phenotypes. The role of such multimodality imaging has been steadily expanding along with recent advancements in surgical techniques and minimally invasive procedures, and the emergence of novel pharmacotherapies directly targeting pathogenic molecules such as myosin inhibitors. Here we review essential knowledge surrounding HCM with a specific focus on structural and functional abnormalities assessed by imaging modalities, leading to treatment strategies.

Right Ventricular Enlargement and Dysfunction Are Associated With Increased All-Cause Mortality in Hypertrophic Cardiomyopathy

ObjectiveTo assess whether right ventricular enlargement (RVE) and right ventricular dysfunction (RVD) adversely affect prognosis in hypertrophic cardiomyopathy (HCM). Patients and MethodsData were retrieved from Mayo Clinic’s prospectively collected HCM registry between January 1, 2000, and September 30, 2012. Right ventricle (RV) size and function were semiquantitatively categorized via echocardiography as normal (RV-Norm) versus abnormal (RV-Abn) (RVE or RVD). All-cause mortality was the primary endpoint. ResultsOf 1878 HCM patients studied (mean age 53±15 years; 41.6% female), only 71 (3.8%) had RV-Abn (24 RVE, 28 RVD, 19 combined RVE and RVD). Compared with HCM patients with RV-Norm, RV-Abn patients were older (57±14 vs 53±15 years, P=.02), more symptomatic (New York Heart Association functional class III-IV in 62.0% vs 48.6%, P=.03), had more atrial fibrillation (53.5% vs 17.3%, P<.001), and more prior implantable cardioverter-defibrillator implantation (23.9% vs 11.3%, P=.02). Median follow-up was 9.4 years with 311 deaths. Patients who were RV-Abn had higher all-cause mortality compared with RV-Norm (log-rank P<.001); 24.1% (95% CI, 15.5% to 35.3%) vs 6.1% (95% CI, 5.1% to 7.3%) at 5 years. In multivariable Cox modeling, RV-Abn (hazard ratio, 1.89; 95% CI, 1.18 to 3.03; P=.008) was associated independently with all-cause mortality after adjusting for age, female sex, New York Heart Association functional class, atrial fibrillation, hypertension, coronary artery disease, implantable cardioverter-defibrillator implantation, beta blocker use, prior septal reduction therapy, resting LV outflow tract gradient, maximal LV wall thickness, and moderate or greater tricuspid regurgitation. ConclusionAlthough perturbations in RV size and function were observed in fewer than 5% of patients with HCM, they were associated with nearly two-fold higher all-cause mortality at long-term follow-up.

Age-related sex differences in the outcomes of patients with hypertrophic cardiomyopathy.

BackgroundWe aimed to clarify the sex differences in various cardiovascular and non-cardiovascular outcomes, and to investigate whether sex differences in outcomes are affected by age in hypertrophic cardiomyopathy (HCM).MethodsA cohort of 835 patients with HCM initially evaluated during 2007–2019 were followed for a median of 6.4 years. Study outcomes were all-cause death, cardiovascular and non-cardiovascular death, sudden cardiac death (SCD)/SCD equivalent events, heart failure (HF) events, and the composite cardiovascular outcome including cardiovascular death, SCD/SCD equivalent events, admission for HF, and heart transplantation.ResultsWomen were 5 years older (women 59.9±13.5 vs. men 54.9±11.4 years), had worse dyspnea, and greater left ventricular (LV) diastolic dysfunction and obstructive physiology at presentation. Women compared to men had higher all-cause mortality and cardiovascular event rates, driven by more cardiovascular deaths and heart failure (HF) events. Conversely, non-cardiovascular mortality was not different between the sexes. Female sex was independently associated with all-cause death (HR 1.88, 95% CI 1.11–3.20) and composite cardiovascular events (HR 3.60, 95% CI 2.00–6.49), independent of age, body mass index, New York Heart Association class, SCD risk score, and LV ejection fraction. When stratified by the age of 60, sex differences were not significant at <60 years; however, at ≥60 years, women had worse LV diastolic function, greater obstructive physiology, as well as worse survival and composite cardiovascular outcomes. Sex differences in outcomes remained consistent after propensity score matching for age and other clinical characteristics.ConclusionsWomen with HCM have worse cardiovascular prognosis than men, driven by higher cardiovascular mortality and HF events. The negative impact of female sex on cardiac function and cardiovascular outcome became prominent at age ≥60 years, suggesting age-related sex differences in the prognosis of HCM.

Anatomical-MRI Correlations in Adults and Children with Hypertrophic Cardiomyopathy.

Hypertrophic Cardiomyopathy (HCM) is the most frequent hereditary cardiovascular disease and the leading cause of sudden cardiac death in young individuals. Advancements in CMR imaging have allowed for earlier identification and more accurate prognosis of HCM. Interventions aimed at slowing or stopping the disease’s natural course may be developed in the future. CMR has been validated as a technique with high sensitivity and specificity, very few contraindications, a low risk of side effects, and is overall a good tool to be employed in the management of HCM patients. The goal of this review is to evaluate the magnetic resonance features of HCM, starting with distinct phenotypic variants of the disease and progressing to differential diagnoses of athlete’s heart, hypertension, and infiltrative cardiomyopathies. HCM in children has its own section in this review, with possible risk factors that are distinct from those in adults; delayed enhancement in children may play a role in risk stratification in HCM. Finally, a number of teaching points for general cardiologists who recommend CMR for patients with HCM will be presented.