The influence of age on gender-specific differences in the left ventricular cavity size and contractility in patients with hypertrophic cardiomyopathy

Gender Related Differences in the Clinical Presentation of Hypertrophic Cardiomyopathy—An Analysis from the SILICOFCM Database

Background and Objectives: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease that affects approximately 1 in 500 people. Due to an incomplete disease penetrance associated with numerous factors, HCM is not manifested in all carriers of genetic mutation. Although about two-thirds of patients are male, it seems that female gender is associated with more severe disease phenotype and worse prognosis. The objective of this study was to evaluate the gender related differences in HCM presentation. Materials and Methods: This study was conducted as a part of the international multidisciplinary SILICOFCM project. Clinical information, laboratory analyses, electrocardiography, echocardiography, and genetic testing data were collected for 362 HCM patients from four clinical centers (Florence, Newcastle, Novi Sad, and Regensburg). There were 33% female patients, and 67% male patients. Results: Female patients were older than males (64.5 vs. 53.5 years, p < 0.0005). The male predominance was present across all age groups until the age of 70, when gender distribution became comparable. Females had higher number of symptomatic individuals then males (69% vs. 52%, p = 0.003), most frequently complaining of dyspnea (50% vs. 30%), followed by chest pain (30% vs. 17%), fatigue (26% vs. 13%), palpitations (22% vs. 13%), and syncope (13% vs. 8%). The most common rhythm disorder was atrial fibrillation which was present in a similar number of females and males (19% vs. 13%, p = 0.218). Levels of N-terminal pro-brain natriuretic peptide were comparable between the genders (571 vs. 794 ng/L, p = 0.244). Echocardiography showed similar thickness of interventricular septum (18 vs. 16 mm, p = 0.121) and posterolateral wall (13 vs. 12 mm, p = 0.656), however, females had a lower number of systolic anterior motion (8% vs. 16%, p = 0.020) and other mitral valve abnormalities. Conclusions: Female patients are underrepresented but seem to have a more pronounced clinical presentation of HCM. Therefore, establishing gender specific diagnostic criteria for HCM should be considered.

Sex differences in the prognosis of patients with hypertrophic cardiomyopathy

We investigated sex-related differences in the prognosis of patients with hypertrophic cardiomyopathy (HCM) using the Korea National Health Insurance Service database. From 2010 to 2016, 9524 patients diagnosed with HCM and had more than 1-year follow-up period were analyzed. The primary endpoint was the composite of cardiovascular death or new-onset heart failure (HF) admission. Propensity score-matching analysis was performed to adjust for different baseline characteristics. With a 4.4-years’ median follow-up interval (range 2.0–6.6 years) and male predominance (77.6%), women with HCM were older (52.6 ± 9.7 vs. 51.4 ± 9.1, p < 0.001), had lower incomes, more comorbidities based on Charlson comorbidity index. Women with HCM had a higher incidence of the primary endpoint than men (incidence rate: 34.15 vs. 22.83 per 1000 person-years, log-rank p < 0.001). Multivariable Cox analysis showed that female sex was a poor prognostic factor for the primary endpoint (HR 1.43, 95% CI 1.24–1.64, p < 0.001). This was mainly driven by a higher incidence of new-onset HF admission (HR 1.55, 95% CI 1.34–1.80). However, there was no difference in the incidence of cardiovascular death between the sexes. This result was concordant in the propensity score-matched cohort. In conclusion, women with HCM have worse prognosis, which was mainly driven by a higher new-onset HF admission.

The Mitral Coaptation to Ventricular Septal Space: Two- and Three-Dimensional Transesophageal Echocardiographic Assessment

OBJECTIVES

To assess the dimensions and changes in the CSEPT (space between the ventricular septum and mitral coaptation point) before and after cardiopulmonary bypass (CPB) and to compare patients with and without aortic valve stenosis (AS) undergoing cardiac surgery.

DESIGN

Retrospective review of intraoperative transesophageal echocardiographic examinations.

SETTING

Single academic medical center.

PARTICIPANTS

The study comprised 91 elective cardiac surgical patients-30 with AS scheduled for aortic valve replacement and 61 without AS (non-AS).

INTERVENTIONS

Two- and 3-dimensional (2D and 3D) analysis of the CSEPT before and after CPB.

MEASUREMENTS AND MAIN RESULTS

Assessment of the CSEPT distances and areas was performed using 2D and 3D imaging before and after CPB. Two-dimensional measures of CSEPT distances were performed using midesophageal 5-chamber and long-axis windows. Three-dimensional measures were performed offline using multiplanar reconstruction. The CSEPT space was smaller after CPB (p < 0.01). Before and after CPB, the midesophageal 5-chamber and long-axis windows were similar to each other, and both were larger than the pre-CPB 3D CSEPT distance. Patients with AS had smaller before and after CPB distances and areas compared with non-AS patients (p < 0.05). The change in CSEPT area in AS patients was 24%.

CONCLUSIONS

The CSEPT space is smaller after CPB and more so for patients with AS undergoing aortic valve replacement. Two-dimensional CEPT distances vary compared with 3D CSEPT distances. Additional study using Doppler analysis will elucidate the added value of 3D assessment of the CSEPT space.

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.

Sex Differences at the Time of Myectomy in Hypertrophic Cardiomyopathy

BACKGROUND

One of the first clinically detectable alterations in heart function in hypertrophic cardiomyopathy (HCM) is a decline in diastolic function. Diastolic dysfunction is caused by changes in intrinsic properties of cardiomyocytes or an increase in fibrosis. We investigated whether clinical and cellular parameters of diastolic function are different between male and female patients with HCM at the time of myectomy.

METHODS AND RESULTS

Cardiac tissue from the interventricular septum of patients with HCM (27 women and 44 men) was obtained during myectomy preceded by echocardiography. At myectomy, female patients were 7 years older than male patients and showed more advanced diastolic dysfunction than men evident from significantly higher values for E/e' ratio, left ventricular filling pattern, tricuspid regurgitation velocity, and left atrial diameter indexed for body surface. Whereas most male patients (56%) showed mild (grade I) diastolic dysfunction, 50% of female patients showed grade III diastolic dysfunction. Passive tension in HCM cardiomyocytes was comparable with controls, and myofilament calcium sensitivity was higher in HCM compared with controls, but no sex differences were observed in myofilament function. In female patients with HCM, titin was more compliant, and more fibrosis was present compared with men. Differences between female and male patients with HCM remained significant after correction for age.

CONCLUSIONS

Female patients with HCM are older at the time of myectomy and show greater impairment of diastolic function. Furthermore, left ventricular and left atrial remodeling is increased in women when corrected for body surface area. At a cellular level, HCM women showed increased compliant titin and a larger degree of interstitial fibrosis.

Effect of Gender and Genetic Mutations on Outcomes in Patients With Hypertrophic Cardiomyopathy

Gender has been proposed to impact the phenotype and prognosis of hypertrophic cardiomyopathy (HC). Our aims were to study gender differences in the clinical presentation, phenotype, genotype, and outcome of HC. This retrospective single-center cohort study included 1,007 patients with HC (62% male, 80% genotyped) evaluated between 1977 and 2017. Hazard ratios (HR) were calculated using multivariable Cox proportional hazard regression models. At first evaluation, female patients presented more often with symptoms (43% vs 35%, p = 0.01), were older than male patients (56 ± 16 vs 49 ± 15 years, p <0.001), and more frequently had hypertension (38% vs 27%, p <0.001), left ventricular outflow tract obstruction (37% vs 27%, p <0.001), and impaired left ventricular systolic (17% vs 11%, p = 0.01) and diastolic (77% vs 62%, p <0.001) function. Overall, the genetic yield was similar between genders (54% vs 51%, p = 0.4); however, in patients ≥70 years, the genetic yield was less in women (15% vs 36%, p = 0.03). During 6.8-year follow-up (interquartile range 3.2 to 10.9), female gender was not independently associated with all-cause mortality (HR 1.25 [0.91 to 1.73]), cardiovascular mortality (HR 1.22 [0.83 to 1.79]), heart failure-related mortality (HR 1.77 [0.95 to 3.27]), or sudden cardiac death (SCD) and/or aborted SCD (HR 0.75 [0.44 to 1.30]). Interventions and nonfatal clinical events did not differ between the genders. In conclusion, female patients with HC present at a more advanced age with a different clinical, phenotypic, and genetic status. There is no independent association between female gender and all-cause mortality, cardiovascular mortality, heart failure-related mortality, or SCD.

The effect of hypertension on cardiac structure and function in different types of hypertrophic cardiomyopathy: A single-center retrospective study

OBJECTIVES

To determine whether hypertension (HTN) affects cardiac structure and function in different types of hypertrophic cardiomyopathy (HCM).

DESIGN

Patients with obstructive HCM (n = 40), septal HCM (n = 88), and apical HCM (n = 42) were separated into hypertensive and non-hypertensive subgroups, and echocardiographic parameters at baseline and at follow-up were compared between the subgroups.

RESULTS

At follow-up, hypertensive obstructive HCM patients showed a decrease in end-diastolic volume (from 93.87 ± 26.08 mL to 79.06 ± 20.07 mL; p= 0.045) and in left ventricular end-diastolic diameter (from 45.00 ± 5.32 mm to 41.83 ± 4.58 mm; p =0.042). Non-hypertensive obstructive HCM patients showed a decrease in maximum aortic velocity (from 2.01 ± 0.53 m/s to 1.28 ± 0.25 m/s; p= 0.011) and in aortic maximum pressure gradient (from 17.22 ± 9.57 mm Hg to 6.79 ± 2.44 mm Hg; p= 0.03). Hypertensive apical HCM patients showed an increase in end-diastolic volume (from 95.28 ± 16.54 mL to 119.74 ± 25.19 mL; p= 0.016) and in left ventricular end-diastolic diameter (from 45.28 ± 3.36 mm to 50.20 ± 4.56 mm; p= 0.007).

CONCLUSIONS

HTN can affect left ventricular capacity in obstructive HCM and apical HCM, causing a decrease in ventricular capacity in the former and increase in the latter; it has no significant effect on the size of the left ventricular cavity in septal HCM. HTN can lead to a poor therapeutic effect on aortic flow rate and pressure gradient in obstructive HCM patients.

Elevated Level of Troponin but Not N-Terminal Probrain Natriuretic Peptide Is Associated with Increased Risk of Sudden Cardiac Death in Hypertrophic Cardiomyopathy Calculated According to the ESC Guidelines 2014

The aim of this study was to assess the relationship between biomarkers (high-sensitive troponin I [hs-TnI], N-Terminal probrain natriuretic peptide [NT-proBNP]) and calculated 5-year percentage risk score of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). Methods. In 46 HCM patients (mean age 39 ± 7 years, 24 males and 22 females), echocardiographic examination, including the stimulating maneuvers to provoke maximized LVOT gradient, had been performed and next ECG Holter was immediately started. After 24 hours, the ECG Holter was finished and the hs-TnI and NT-proBNP have been measured. Patients were divided according to 1/value of both biomarkers (hs-TnI-positive and hs-TnI-negative subgroups) and 2/(NT-proBNP lower and higher subgroup divided by median). Results. In comparison between 19 patients (hs-TnI positive) versus 27 patients (hs-TnI negative), the calculated 5-year percentage risk of SCD in HCM was significantly greater (6.38 ± 4.17% versus 3.81 ± 3.23%, P < 0.05). In comparison between higher NT-proBNP versus lower NT-proBNP subgroups, the calculated 5-year percentage risk of SCD in HCM was not significantly greater (5.18 ± 3.63% versus 4.14 ± 4.18%, P > 0.05). Conclusions. Patients with HCM and positive hs-TnI test have a higher risk of SCD estimated according to SCD calculator recommended by the ESC Guidelines 2014 than patients with negative hs-TnI test.

Obstructive Form of Hypertrophic Cardiomyopathy-Left Ventricular Outflow Tract Gradient: Novel Methods of Provocation, Monitoring of Biomarkers, and Recent Advances in the Treatment

Dynamic (latent or/and labile) obstruction of left ventricular outflow (LVOT) was recognized from the earliest clinical descriptions of hypertrophic cardiomyopathy (HCM) and has proved to be a complex phenomenon, as well as arguably the most audible (“visible”) pathophysiological hallmark of this heterogeneous disease. The aim of the current review is focused on two novel issues in a subgroup of obstructive HCM. Firstly, the important methodological problem in HCM is the examination of a subgroup of patients with nonobstructive hypertrophy in resting conditions and hard, but possible provoking obstruction. Recently, investigators have proposed physiological stress test (with double combined stimuli) to disclose such type of patients. The upright exercise is described in the ESC guideline on hypertrophic cardiomyopathy from 2014 and may appear as a candidate for gold standard provocation test. The second novel area of interest is associated with elevated level of signaling biomarkers: hypercoagulation, hemolysis, acquired von Willebrand 2A disease, and enhanced oxidative stress. The accelerated and turbulent flow within narrow LVOT may be responsible for these biochemical disturbances. The most recent advances in the treatment of obstructive HCM are related to nonpharmacological methods of LVOT gradient reduction. This report extensively discusses novel methods.

Sex dimorphisms of crossbridge cycling kinetics in transgenic hypertrophic cardiomyopathy mice

Familial hypertrophic cardiomyopathy (HCM) is a disease of the sarcomere and may lead to hypertrophic, dilated, restrictive, and/or arrhythmogenic cardiomyopathy, congestive heart failure, or sudden cardiac death. We hypothesized that hearts from transgenic HCM mice harboring a mutant myosin heavy chain increase the energetic cost of contraction in a sex-specific manner. To do this, we assessed Ca(2+) sensitivity of tension and crossbridge kinetics in demembranated cardiac trabeculas from male and female wild-type (WT) and HCM hearts at an early time point (2 mo of age). We found a significant effect of sex on Ca(2+) sensitivity such that male, but not female, HCM mice displayed a decrease in Ca(2+) sensitivity compared with WT counterparts. The HCM transgene and sex significantly impacted the rate of force redevelopment by a rapid release-restretch protocol and tension cost by the ATPase-tension relationship. In each of these measures, HCM male trabeculas displayed a gain-of-function when compared with WT counterparts. In addition, cardiac remodeling measured by echocardiography, histology, morphometry, and posttranslational modifications demonstrated sex- and HCM-specific effects. In conclusion, female and male HCM mice display sex dimorphic crossbridge kinetics accompanied by sex- and HCM-dependent cardiac remodeling at the morphometric, histological, and cellular level.

Sex-dependent pathophysiological mechanisms in hypertrophic cardiomyopathy: implications for rhythm disorders

Differences in cardiac physiology are seen between men and women in terms of health and disease. Sex differences start to develop at puberty and are maintained during aging. The prevalence of almost all cardiovascular diseases is found to be higher in men than in women, and disease progression tends to be more rapid in male than in female patients. In cohorts of patients with hypertrophic cardiomyopathy (HCM), the most common autosomal inherited cardiac disease, men are overrepresented, suggesting increased penetrance of HCM-causing mutations in male patients. Cardiac remodeling in patients with HCM is higher in men than in women, the same is seen in HCM animal models. Patients with HCM are at increased risk of sudden cardiac death (SCD) and developing rhythm disorders. There seems to be no sex effect on the risk of SCD or arrhythmias in patients with HCM; however, animal studies suggest that certain mutations predispose men to SCD.

Hypertrophic cardiomyopathy with longevity to 90 years or older

Hypertrophic cardiomyopathy (HC) is the most common cause of sudden death in the young, but survival to particularly advanced age is less well appreciated. The investigators report the prevalence, clinical features, and demographics of patients with HC surviving to ≥90 years of age. Of 1,297 patients with HC in the Hypertrophic Cardiomyopathy Center database (Minneapolis Heart Institute Foundation), 26 (2.0%) were identified who had achieved the age of ≥90 years; 18 (69%) were women. HC diagnosis came late in life, at 61 to 92 years (mean 80 ± 8; ≥75 years in 21 patients), recognized fortuitously by the detection of a heart murmur or during family screening (n = 6) or after onset of new symptoms (n = 20). At most recent evaluation (or death) patients were aged 90 to 96.7 years (mean 92.2 ± 2), with 6 presently alive at 91 to 96 years of age; HC did not appear to be the primary cause of death in any patient. Left ventricular wall thicknesses were 15 to 31 mm (mean 20 ± 3); 8 patients (31%) had obstruction to left ventricular outflow at rest (peak instantaneous gradients, 38 to 135 mm Hg). Significant HC-related complications occurred in 13 patients (50%), including progressive heart failure symptoms, atrial fibrillation, and nonfatal embolic stroke. Although no patient died suddenly, 13 (50%) nevertheless carried conventional HC risk markers. A greater proportion of cohort patients reached ≥90 years of age (2.0%) than expected in the general population (0.8%) (p <0.001). In conclusion, HC may be unrecognized until late in life and is consistent with survival to particularly advanced age into the 10th decade of life without the need for major HC-related treatment interventions, and with demise ultimately largely unrelated to this disease. This principle regarding the natural history of HC can afford a measure of reassurance to many patients.

What we know and do not know about sex and cardiac disease

Cardiovascular disease (CVD) remains the single leading cause of death in both men and women. A large proportion of the population with CVD will die with a diagnosis of congestive heart failure (CHF). It is becoming increasingly recognized that sex differences exist in the etiology, development, and outcome of CHF. For example, compared to male counterparts, women that present with CHF are typically older and have systolic cardiac function that is not impaired. Despite a growing body of literature addressing the underlying mechanisms of sex dimorphisms in cardiac disease, there remain significant inconsistencies reported in these studies. Given that the development of CHF results from the complex integration of genetic and nongenetic cues, it is not surprising that the elucidation and subsequent identification of molecular mechanisms remains unclear. In this review, key aspects of sex differences in CVD and CHF will be highlighted with an emphasis on some of the unanswered questions regarding these differences. The contention is presented that it becomes critical to reference cellular mechanisms within the context of each sex to better understand these sex dimorphisms.

Relationship between sex, shape, and substrate in hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a disease characterized by substantial genetic, morphologic, and prognostic heterogeneity. Recently, sex-related differences in HCM were reported, with women being older at diagnosis and exhibiting greater left ventricular outflow tract obstruction than men. We sought to evaluate the influence of sex on the HCM phenotype in a large cohort of unrelated patients with genetically and morphologically classified HCM.

METHODS

Comprehensive genotyping of 13 HCM-susceptibility genes encoding myofilament and Z-disc proteins of the cardiac sarcomere was performed previously on 382 unrelated patients with HCM. Blinded to the genotype, the septal morphology was graded as reverse-curvature, sigmoidal, apical, or neutral-contour HCM by echocardiography.

RESULTS

Overall, women (a) were significantly older at diagnosis (45.1 +/- 20 vs 35.8 +/- 17 years, P < .001), (b) had greater left ventricular outflow tract obstruction (53.5 +/- 45 vs 41.7 +/- 42 mm Hg, P = .009), (c) were more likely to have concomitant hypertension (19% vs 11%, P = .02), and (d) had a higher rate of surgical myectomy (49% vs 36%, P = .01) than men. Interestingly, these sex-based differences were apparent only among patients with sigmoidal HCM (P < .001).

CONCLUSIONS

In this largest cohort of comprehensively genotyped and morphologically classified patients with clinically diagnosed HCM, we observed that the striking sex-related differences in the clinical phenotype are confined largely to the subset of mutation-negative sigmoidal HCM. Whereas mutations within the sarcomere appear to dominate the disease process, in their absence, sex has a significant modifying effect, specifically noted in cases of sigmoidal HCM.

Myofilament mechanical performance is enhanced by R403Q myosin in mouse myocardium independent of sex

Male but not female mice carrying a single R403Q missense allele for cardiac alpha-myosin heavy chain (M-alphaMHC(R403Q/+) and F-alphaMHC(R403Q/+), respectively) develop significant hypertrophic cardiomyopathy (HCM) compared with male and female wild-type mice (M-alphaMHC(+/+) and F-alphaMHC(+/+), respectively) after approximately 30 wk of age. We tested the hypothesis that myofilament mechanical performance differs between M-alphaMHC(R403Q/+) and F-alphaMHC(R403Q/+) at younger ages (10-20 wk) and could account for sex differences in HCM development. The sensitivity of chemically skinned myocardial strips to Ca(2+) activation (pCa(50)) was significantly (P < 0.05) enhanced in male mice independent of genotype (M-alphaMHC(R403Q/+): 5.70 +/- 0.06, M-alphaMHC(+/+): 5.63 +/- 0.05, F-alphaMHC(R403Q/+): 5.57 +/- 0.03, F-alphaMHC(+/+): 5.54 +/- 0.04) by two-way ANOVA, whereas maximum developed tension was significantly enhanced in alpha-MHC(R403Q/+) independent of sex (M-alphaMHC(R403Q/+): 29.3 +/- 2.3, M-alphaMHC(+/+): 26.0 +/- 1.4, F-alphaMHC(R403Q/+): 30.2 +/- 2.1, F-alphaMHC(+/+): 26.2 +/- 1.2 mN/mm(2)). The frequency of maximum work generated by sinusoidal length perturbation was significantly higher in alphaMHC(R403Q/+) mice than in sex-matched controls (M-alphaMHC(R403Q/+): 2.26 +/- 0.47, M-alphaMHC(+/+): 1.29 +/- 0.18, F-alphaMHC(R403Q/+): 3.21 +/- 0.33, F-alphaMHC(+/+): 2.52 +/- 0.36 Hz). Unloaded shortening velocity was significantly enhanced in alphaMHC(R403Q/+) and in female mice (M-alphaMHC(R403Q/+): 2.26 +/- 0.47, M-alphaMHC(+/+): 1.29 +/- 0.18, F-alphaMHC(R403Q/+): 3.21 +/- 0.33, F-alphaMHC(+/+): 2.52 +/- 0.36 muscle lengths/s), and normalized mechanical power, calculated from the tension-velocity relationship, was significantly enhanced in alphaMHC(R403Q/+) independent of sex (M-alphaMHC(R403Q/+): 60 +/- 2 10(-3), M-alphaMHC(+/+): 37 +/- 3 10(-3), F-alphaMHC(R403Q/+): 57 +/- 3 10(-3), F-alphaMHC(+/+) 25 +/- 3 10(-3) muscle lengths/s x normalized tension). We did not find a statistically significant sex x mutation interaction for any measure of myofilament performance. Therefore, sarcomeric incorporation of the R403Q myosin similarly enhanced left ventricular myofilament mechanical performance in both male and female mice. The sex-dependent development of HCM due to the R403Q myosin may then be inhibited by female sex hormones, which may additionally underlie the observed sex differences for pCa(50) and unloaded shortening velocity.

Gender-specific clinical characteristics of deep Q waves in hypertrophic cardiomyopathy

BACKGROUND

Despite male predominance in the prevalence of hypertrophic cardiomyopathy (HCM), repeated diagnosis at our institute indicates a possible higher prevalence of deep Q waves with HCM in women.

OBJECTIVE

The current study examined gender similarities and differences in the prevalence of deep Q waves in HCM and in the morphologic and electrocardiographic features of HCM with deep Q waves.

METHODS

Patients with HCM underwent cardiac magnetic resonance (CMR) imaging to identify the prevalence of deep Q waves in electrocardiographic limb leads, and to analyze the relationship between distribution patterns of deep Q waves and those of the localization of maximum amplitude of left ventricular (LV) hypertrophy. Contiguous LV short-axis images were obtained from the base toward the apex.

RESULTS

Of the 200 consecutive patients (172 males, aged 20-78 years; 28 females, aged 16-79 years) with HCM who underwent CMR imaging, 10 male and 8 female patients had deep Q waves. Deep Q waves were more prevalent in females with HCM than in their male counterparts (28.6% vs 5.8%, respectively; P<0.001). Of the 18 patients with deep Q waves, maximum wall thickness was localized at either the basal anterior wall or the midventricular septum in 9 (90%) of the 10 male patients and 6 (75%) of the 8 female patients. In both sexes, the Q wave distribution pattern of I and aVL and of II and aVF indicated localization of maximum hypertrophy at the midventricular septum in 6 (75%) of the 8 patients with the former pattern, and at the basal anterior wall in 9 (90%) of the 10 patients with the latter pattern.

CONCLUSIONS

Diagnostic deep Q waves were detected more frequently in female patients with HCM than in their male counterparts. In HCM with deep Q waves in limb leads, morphologic and electrocardiographic analysis showed similar features in both sexes.

Changes with age in left ventricular function and volumes at rest and postexercise in postmenopausal women

OBJECTIVES

In postmenopausal women, it has been reported that the plasma estrogen levels diminish immediately after menopause, and that this phenomenon affects left ventricular (LV) function and volumes. However, the effects of age on LV function and volumes for a relatively short period in the postmenopausal women remain to be established. Electrocardiographically gated-myocardial single-photon emission computed tomography (SPECT) has recently provided accurate estimations of perfusion, cardiac systolic and diastolic functions. We investigated the age-related changes in LV function and volumes in postmenopausal women using electrocardiographically gated-myocardial scintigraphy.

METHODS

Twenty-two consecutive healthy postmenopausal women (mean age of 63.8 +/- 9.4 years, from 42 to 77 years) without cardiac disease underwent stress/rest technetium-99m tetrofosmin gated-myocardial SPECT with 16 frames per cardiac cycle at baseline and follow-up (1.0 +/- 0.3 years later). LV ejection fraction (LVEF) and LV volumes were calculated by QGS software. Fourier series were retained for the analysis of the volume curve. From this volume curve, we derived the following diastolic indices: peak filling rate (PFR) and time to PFR (TPFR).

RESULTS

End-systolic volume index (ESVI) significantly decreased at postexercise (p = 0.02) and tended to decrease at rest (p = 0.06) from the baseline to the follow-up study. LVEF significantly increased at both postexercise (p = 0.01) and rest (p = 0.03) from the baseline to the follow-up study. The TPFR at rest tended to be prolonged from the baseline to the follow-up study (p = 0.07). The absolute increase in LVEF at postexercise tended to decrease with age [4.8% (50s) vs. 3.4% (60s) vs. 1.2% (70s)].

CONCLUSIONS

An age-related change in cardiac performance is apparent at an approximately 1 year follow-up in postmenopausal women. In particular, the increase in LV systolic function tends to show the greatest value in the 50s subjects among the 3 generations.

The genetic basis for cardiac remodeling

Cardiomyopathies are primary disorders of cardiac muscle associated with abnormalities of cardiac wall thickness, chamber size, contraction, relaxation, conduction, and rhythm. They are a major cause of morbidity and mortality at all ages and, like acquired forms of cardiovascular disease, often result in heart failure. Over the past two decades, molecular genetic studies of humans and analyses of model organisms have made remarkable progress in defining the pathogenesis of cardiomyopathies. Hypertrophic cardiomyopathy can result from mutations in 11 genes that encode sarcomere proteins, and dilated cardiomyopathy is caused by mutations at 25 chromosome loci where genes encoding contractile, cytoskeletal, and calcium regulatory proteins have been identified. Causes of cardiomyopathies associated with clinically important cardiac arrhythmias have also been discovered: Mutations in cardiac metabolic genes cause hypertrophy in association with ventricular pre-excitation and mutations causing arrhythmogenic right ventricular dysplasia were recently discovered in protein constituents of desmosomes. This considerable genetic heterogeneity suggests that there are multiple pathways that lead to changes in heart structure and function. Defects in myocyte force generation, force transmission, and calcium homeostasis have emerged as particularly critical signals driving these pathologies. Delineation of the cell and molecular events triggered by cardiomyopathy gene mutations provide new fundamental knowledge about myocyte biology and organ physiology that accounts for cardiac remodeling and defines mechanistic pathways that lead to heart failure.

Gender-related differences in the clinical presentation and outcome of hypertrophic cardiomyopathy

OBJECTIVES

The goal of this study was to assess gender-related differences in a multicenter population with hypertrophic cardiomyopathy (HCM).

BACKGROUND

Little is known regarding the impact of gender on the heterogeneous clinical profile and clinical course of HCM.

METHODS

We studied 969 consecutive HCM patients from Italy and the U.S. followed over 6.2 +/- 6.1 years.

RESULTS

Male patients had a 3:2 predominance (59%), similar in Italy and the U.S. (p = 0.24). At initial evaluation, female patients were older and more symptomatic than male patients (47 +/- 23 years vs. 38 +/- 18 years; p < 0.001; mean New York Heart Association [NYHA] functional class 1.8 +/- 0.8 vs. 1.4 +/- 0.6; p < 0.001), and more frequently showed left ventricular outflow obstruction (37% vs. 23%; p < 0.001). Moreover, female patients were less often diagnosed fortuitously by routine medical examination (23% vs. 41% in male patients, p < 0.001). Female gender was independently associated with the risk of symptom progression to NYHA functional classes III/IV or death from heart failure or stroke compared with male gender (independent relative hazard 1.5; p < 0.001), particularly patients > or =50 years of age and with resting outflow obstruction (p < 0.005). Hypertrophic cardiomyopathy-related mortality and risk of sudden death were similar in men and women.

CONCLUSIONS

Women with HCM were under-represented, older, and more symptomatic than men, and showed higher risk of progression to advanced heart failure or death, often associated with outflow obstruction. These gender-specific differences suggest that social, endocrine, or genetic factors may affect the diagnosis and clinical course of HCM. A heightened suspicion for HCM in women may allow for timely implementation of treatment strategies, including relief of obstruction and prevention of sudden death or stroke.

Clinical characteristics of and long-term outcome in Chinese patients with hypertrophic cardiomyopathy

BACKGROUND

Data on the phenotypical pattern and natural history of hypertrophic cardiomyopathy in Chinese patients are very limited. The purpose of this study was to describe the clinical characteristics of and long-term outcome in Chinese patients with hypertrophic cardiomyopathy.

METHODS

We evaluated 118 Chinese patients (62 male) who were diagnosed with hypertrophic cardiomyopathy at Queen Mary Hospital from 1973 to 2002. Diagnosis was based on the demonstration of left ventricular hypertrophy (wall thickness > or =15 mm during diastole), either in a specific region or with diffuse distribution, using echocardiography or magnetic resonance imaging. Clinical predictors of major cardiovascular events related to hypertrophic cardiomyopathy (cardiovascular death, potentially fatal cardiac arrhythmia, and refractory heart failure requiring cardiac transplantation or percutaneous alcohol septal ablation) were evaluated with univariate and multivariate Cox proportional hazards regression models.

RESULTS

The mean (+/- SD) age at presentation was 54 +/- 18 years. During a mean follow-up of 5.8 +/- 4.3 years (range, 1 to 29 years) from presentation, major cardiovascular events related to hypertrophic cardiomyopathy occurred in 19 patients (16%), including 9 deaths. Annual cardiovascular mortality was 1.6%. Fifty-five patients (47%) had one or more cardiovascular complications related to hypertrophic cardiomyopathy, of which atrial fibrillation was the most common (35%, n = 41). The most common type of hypertrophic cardiomyopathy was the apical variant (41%, n = 49). In multivariate analysis, female sex was the only independent predictor of major cardiovascular events related to hypertrophic cardiomyopathy (hazard ratio = 5.86; 95% confidence interval: 1.77 to 7.21; P = 0.007).

CONCLUSION

Hypertrophic cardiomyopathy in Chinese patients is characterized by late onset of presentation, a high incidence of the apical form of the condition, and adverse clinical outcome in female patients, which suggest a different phenotypical pattern than in white patients.