Prognostic Significance of Left Atrial Volume Dilatation in Patients with Hypertrophic Cardiomyopathy

Sex-Related Differences in Left Ventricular Geometry Patterns in Patients With Arterial Hypertension

Background

Sex-specific differences in left ventricular (LV) geometry might help in developing tailored strategies for hypertension management.

Objectives

The purpose of the study was to evaluate sex-related differences in LV geometry at baseline and over time in hypertension.

Methods

From a prospective registry, we included hypertensives without prevalent cardiovascular disease, incident myocardial infarction, chronic kidney disease > stage III, and with normal LV ejection fraction. LV mass index >115 g/m2 in males and >95 g/m2 in females, identified LV hypertrophy (LVH). Relative wall thickness ≥0.43 defined LV concentric geometry. LVH in presence of concentric geometry was defined as concentric LVH, whereas relative wall thickness <0.43 was categorized as eccentric. Concentric geometry, or LVH, identified LV remodeling.

Results

Six thousand four hundred twenty-seven patients (age 53 ± 11 years, 43% females) were included. At baseline, females showed lower prevalence of normal geometric pattern and higher prevalence of LVH than males (50% vs 72%, P < 0.001; 47% vs 23%, P < 0.001, respectively), with a higher prevalence of eccentric LVH (40% vs 18%, P < 0.001). Female sex was independently associated with LV remodeling (OR: 2.36; 95% CI: 2.12-2.62; P < 0.001). At long-term follow-up (mean 6.1 years, IQR: 2.8-8.6 years), prevalence of LV remodeling increased in both sexes, although a normal LV geometry remained less frequent in females than males (43% vs 67%, P < 0.001), with differences persisting in eccentric (41% vs 21%, P < 0.001) and concentric LVH (11% vs 5%, P < 0.001).

Conclusions

We found sex-related differences in LV geometry among hypertensives. Females have higher risk of LV remodeling at baseline compared with males, with differences persisting at long-term follow-up.

Effect of Aficamten on Cardiac Structure and Function in Obstructive Hypertrophic Cardiomyopathy: SEQUOIA-HCM CMR Substudy

BACKGROUND

Obstructive hypertrophic cardiomyopathy (oHCM) is characterized by left ventricular (LV) hypertrophy, LV outflow tract obstruction, and left atrial dilation, which can be associated with progressive heart failure, atrial fibrillation, and stroke. Aficamten is a next-in-class cardiac myosin inhibitor that reduces outflow tract obstruction by modulating cardiac contractility, with the potential to reverse pathological remodeling and, in turn, reduce cardiovascular events.

OBJECTIVES

This study sought to investigate the effect of aficamten on cardiac remodeling compared with placebo using cardiovascular magnetic resonance (CMR) and its association with key clinical endpoints in the SEQUOIA-HCM (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM) CMR substudy.

METHODS

SEQUOIA-HCM was a phase 3 double-blind, placebo-controlled trial for adults with symptomatic oHCM who were randomized 1:1 to 24 weeks of aficamten (dose range: 5-20 mg) or placebo. Eligible participants were offered enrollment in the CMR substudy with studies performed at baseline and week 24. Image analysis was performed in a blinded fashion by a core laboratory.

RESULTS

Of the 282 randomized patients, 57 (20%) participated in the substudy, and of those, 50 (88%) completed both baseline and week 24 CMR. Baseline characteristics of the CMR cohort were similar to the overall study population. Of these 50 patients, 21 received aficamten and 29 received placebo. Relative to placebo, patients receiving aficamten demonstrated significant reductions (Δ least-squares mean) in LV mass index (-15 g/m2; 95% CI: -25 to -6 g/m2; P = 0.001), maximal LV wall thickness (-2.1 mm; 95% CI: -3.1 to -1.1 mm; P < 0.001), left atrial volume index (-13 mL/m2; 95% CI: -19 to -7 mL/m2; P < 0.001), native T1 relaxation time (-37 ms; 95% CI: -69 to -5 ms; P = 0.026), indexed extracellular volume fraction (-3.9 g/m2; 95% CI: -7.0 to -0.9 g/m2; P = 0.014), and indexed myocyte mass (-14 g/m2; 95% CI: -23 to -4 g/m2; P = 0.004), while there were no significant changes in LV chamber volumes, LV replacement fibrosis (late gadolinium enhancement mass -0.7 g; 95% CI: -2.9 to 1.6 g; P = 0.54), or extracellular volume (0.7%; 95% CI: -2.2% to 3.6%; P = 0.61).

CONCLUSIONS

The CMR substudy of SEQUOIA-HCM demonstrated that treatment with aficamten relative to placebo for 24 weeks resulted in favorable cardiac remodeling. These changes, particularly with regard to LV mass, wall thickness, and left atrial size, could potentially lead to reduced cardiovascular events including heart failure and atrial fibrillation with longer follow-up. (Phase 3 Trial to Evaluate the Efficacy and Safety of Aficamten Compared to Placebo in Adults With Symptomatic oHCM [SEQUOIA-HCM]; NCT05186818).

Echocardiographic Strain Abnormalities Precede Left Ventricular Hypertrophy Development in Hypertrophic Cardiomyopathy Mutation Carriers

Hypertrophic cardiomyopathy (HCM) is a genetic disease characterized by unexplained left ventricular hypertrophy (LVH), diastolic dysfunction, and increased sudden-death risk. Early detection of the phenotypic expression of the disease in genetic carriers without LVH (Gen+/Phen-) is crucial for emerging therapies. This clinical study aims to identify echocardiographic predictors of phenotypic development in Gen+/Phen-. Sixteen Gen+/Phen- (one subject with troponin T, six with myosin heavy chain-7, and nine with myosin-binding protein C3 mutations), represented the study population. At first and last visit we performed comprehensive 2D speckle-tracking strain echocardiography. During a follow-up of 8 ± 5 years, five carriers developed LVH (LVH+). At baseline, these patients were older than those who did not develop LVH (LVH-) (30 ± 8 vs. 15 ± 8 years, p = 0.005). LVH+ had reduced peak global strain rate during the isovolumic relaxation period (SRIVR) (0.28 ± 0.05 vs. 0.40 ± 0.11 1/s, p = 0.048) and lower global longitudinal strain (GLS) (-19.8 ± 0.4 vs. -22.3 ± 1.1%; p < 0.0001) than LVH- at baseline. SRIVR and GLS were not correlated with age (overall, p > 0.08). This is the first HCM study investigating subjects before they manifest clinically significant or relevant disease burden or symptomatology, comparing at baseline HCM Gen+/Phen- subjects who will develop LVH with those who will not. Furthermore, we identified highly sensitive, easily obtainable, age- and load-independent echocardiographic predictors of phenotype development in HCM gene carriers who may undergo early preventive treatment.

Prognostic Value of Mitral Regurgitation in Patients with Primary Hypertrophic Cardiomyopathy

Background and Objectives: Mitral valve pathology and mitral regurgitation (MR) are very common in patients with hypertrophic cardiomyopathy (HCM), and the evaluation of mitral valve anatomy and degree of MR is important in patients with HCM. The aim of our study was to examine the potential influence of moderate or moderately severe MR on the prognosis, clinical presentation, and structural characteristics of HCM patients. Materials and Methods: A prospective study examined 176 patients diagnosed with primary asymmetric HCM. According to the severity of the MR, the patients were divided into two groups: Group 1 (n = 116) with no/trace or mild MR and Group 2 (n = 60) with moderate or moderately severe MR. All patients had clinical and echocardiographic examinations, as well as a 24 h Holter ECG. Results: Group 2 had significantly more often the presence of the obstructive type of HCM (p < 0.001), syncope (p = 0.030), NYHA II class (p < 0.001), and atrial fibrillation (p = 0.023). Also, Group 2 had an enlarged left atrial dimension (p < 0.001), left atrial volume index (p < 0.001), and indirectly measured systolic pressure in the right ventricle (p < 0.001). Patients with a higher grade of MR had a significantly higher E/e' (p < 0.001) and, as a result, higher values of Nt pro BNP values (p < 0.001) compared to Group 1. Kaplan-Meier analysis demonstrated that the event-free survival rate during a median follow-up of 88 (IQR 40-112) months was significantly higher in Group 1 compared to Group 2 (84% vs. 45% at 8 years; log-rank 20.4, p < 0.001). After adjustment for relevant confounders, the presence of moderate or moderately severe MR remained as an independent predictor of adverse outcomes (HR 2.788; 95% CI 1.221-6.364, p = 0.015). Conclusions: The presence of moderate or moderately severe MR was associated with unfavorable long-term outcomes in HCM patients.

Role and Clinical Importance of Progressive Changes in Echocardiographic Parameters in Predicting Outcomes in Patients With Hypertrophic Cardiomyopathy

BACKGROUND

The prognostic utility of follow-up transthoracic echocardiography (FU-TTE) in patients with hypertrophic cardiomyopathy (HCM) is unclear, specifically in terms of whether changes in echocardiographic parameters in routine FU-TTE parameters are associated with cardiovascular outcomes.

METHODS

From 2010 to 2017, 162 patients with HCM were retrospectively enrolled in this study. Using echocardiography, HCM was diagnosed based on morphological criteria. Patients with other diseases that cause cardiac hypertrophy were excluded. TTE parameters at baseline and FU were analyzed. FU-TTE was designated as the last recorded value in patients who did not develop any cardiovascular event or the latest exam before event development. Clinical outcomes were acute heart failure, cardiac death, arrhythmia, ischemic stroke, and cardiogenic syncope.

RESULTS

Median interval between the baseline TTE and FU-TTE was 3.3 years. Median clinical FU duration was 4.7 years. Septal trans-mitral velocity/mitral annular tissue Doppler velocity (E/e'), tricuspid regurgitation velocity, left ventricular ejection fraction (LVEF), and left atrial volume index (LAVI) at baseline were recorded. LVEF, LAVI, and E/e' values were associated with poor outcomes. However, no delta values predicted HCM-related cardiovascular outcomes. Logistic regression models incorporating changes in TTE parameters had no significant findings. Baseline LAVI was the best predictor of a poor prognosis. In survival analysis, an already enlarged or increased size LAVI was associated with poorer clinical outcomes.

CONCLUSIONS

Changes in echocardiographic parameters extracted from TTE did not assist in predicting clinical outcomes. Cross-sectionally evaluated TTE parameters were superior to changes in TTE parameters between baseline and FU at predicting cardiovascular events.

Recommendations for Multimodality Cardiovascular Imaging of Patients with Hypertrophic Cardiomyopathy: An Update from the American Society of Echocardiography, in Collaboration with the American Society of Nuclear Cardiology, the Society for Cardiovascular Magnetic Resonance, and the Society of Cardiovascular Computed Tomography

Hypertrophic cardiomyopathy (HCM) is defined by the presence of left ventricular hypertrophy in the absence of other potentially causative cardiac, systemic, syndromic, or metabolic diseases. Symptoms can be related to a range of pathophysiologic mechanisms including left ventricular outflow tract obstruction with or without significant mitral regurgitation, diastolic dysfunction with heart failure with preserved and heart failure with reduced ejection fraction, autonomic dysfunction, ischemia, and arrhythmias. Appropriate understanding and utilization of multimodality imaging is fundamental to accurate diagnosis as well as longitudinal care of patients with HCM. Resting and stress imaging provide comprehensive and complementary information to help clarify mechanism(s) responsible for symptoms such that appropriate and timely treatment strategies may be implemented. Advanced imaging is relied upon to guide certain treatment options including septal reduction therapy and mitral valve repair. Using both clinical and imaging parameters, enhanced algorithms for sudden cardiac death risk stratification facilitate selection of HCM patients most likely to benefit from implantable cardioverter-defibrillators.

Projecting the Long-term Clinical Value of Mavacamten for the Treatment of Obstructive Hypertrophic Cardiomyopathy in the United States: An Assessment of Net Health Benefit

PURPOSE

The aim of the study was to project the long-term net health benefits of mavacamten for the treatment of symptomatic obstructive hypertrophic cardiomyopathy (HCM) in the United States.

METHODS

A Markov model with 4 mutually exclusive health states (New York Heart Association [NYHA] functional classes I, II, and III/IV and death) was developed to project the life-years (LYs) and quality-adjusted life-years (QALYs) over a lifetime horizon for patients with symptomatic obstructive HCM receiving mavacamten with or without β-blocker (BB) or calcium channel blocker (CCB) monotherapy or placebo with or without BB or CCB monotherapy. The model simulated a patient cohort with a starting age of 59 years and 41% women. Transition probabilities across NYHA functional classes were estimated using data from the Phase III Clinical Study to Evaluate Mavacamten (MYK-461) in Adults With Symptomatic Obstructive Hypertrophic Cardiomyopathy (EXPLORER-HCM) and the EXPLORER long-term extension (EXPLORER-LTE) cohort from the Long-term Safety Extension Study of Mavacamten in Adults who Have Completed MAVERICK-HCM or EXPLORER-HCM (MAVA-LTE) trial and were extrapolated after week 30. The mortality risks of NYHA functional class I were assumed to be the age- and sex-specific mortality risks of the US general population. The mortality risks for NYHA class II and III/IV were estimated using those for class I in conjunction with the relative mortality risks derived using patients with obstructive HCM from a large real-world registry. Health state utilities for each treatment were estimated from EXPLORER-HCM. Both LYs and QALYs were aggregated over a lifetime for each treatment arm, discounted at 3% annually, and compared between the 2 arms. Sensitivity analyses were conducted to evaluate the robustness of the model findings.

FINDINGS

Over a lifetime, treatment with mavacamten with or without BB or CCB monotherapy was associated with 3.67 incremental LYs compared with placebo with or without BB or CCB monotherapy (13.00 vs 9.33 LYs). Compared with individuals in the placebo group, patients in the mavacamten group were projected to spend 6.17 additional LYs in NYHA functional class I and 0.04 and 2.46 fewer LYs in NYHA functional classes II and III/IV, respectively. With utilities incorporated, mavacamten with or without BB or CCB monotherapy was associated with 4.17 additional QALYs compared with placebo with or without BB or CCB monotherapy (11.74 vs 7.57 QALYs). In the sensitivity analyses, incremental benefits ranged from 1.55 to 6.21 LYs and from 2.48 to 6.19 QALYs across the scenarios.

IMPLICATIONS

This model projected substantial net health benefits associated with mavacamten for symptomatic obstructive HCM owing to improved patient survival and quality of life. The projected QALY gain underscored the likely long-term clinical value of mavacamten in symptomatic obstructive HCM.

Prognostic Value of Transthoracic Doppler Echocardiography Coronary Flow Velocity Reserve in Patients With Asymmetric Hypertrophic Cardiomyopathy

Background

Microvascular dysfunction might be a major determinant of clinical deterioration and outcome in patients with hypertrophic cardiomyopathy (HCM). However, long‐term prognostic value of transthoracic Doppler echocardiography (TDE) coronary flow velocity reserve (CFVR) on clinical outcome is uncertain in HCM patients. Therefore, the aim of our study was to assess long‐term prognostic value of CFVR on clinical outcome in HCM population.

Methods and Results

We prospectively included 150 HCM patients (82 women; mean age 48±15 years). Patients’ clinical characteristics, echocardiographic and CFVR findings (both for left anterior descending [LAD] and posterior descending artery [PD]), were assessed in all patients. The primary outcome was a composite of: HCM related death, heart failure requiring hospitalization, sustained ventricular tachycardia and ischemic stroke. Patients were stratified into 2 subgroups depending on CFVR LAD value: Group 1 (CFVR LAD>2, [n=87]) and Group 2 (CFVR LAD≤2, [n=63]). During a median follow‐up of 88 months, 41/150 (27.3%) patients had adverse cardiac events. In Group 1, there were 8/87 (9.2%), whereas in Group 2 there were 33/63 (52.4%, P<0.001 vs. Group 1) adverse cardiac events. By Kaplan‐Meier analysis, patients with preserved CFVR LAD had significantly higher cumulative event‐free survival rate compared to patients with impaired CFVR LAD (96.4% and 90.9% versus 66.9% and 40.0%, at 5 and 8 years, respectively: log‐rank 37.2, P<0.001). Multivariable analysis identified only CFVR LAD≤2 as an independent predictor for adverse cardiac outcome (HR 6.54; 95% CI 2.83–16.30, P<0.001), while CFVR PD was not significantly associated with outcome.

Conclusions

In patients with HCM, impaired CFVR LAD (≤2) is a strong, independent predictor of adverse cardiac outcome. When the aim of testing is HCM risk stratification and CFVR LAD data are available, the evaluation of CFVR PD is redundant.

A Heterozygous Mutation in Cardiac Troponin T Promotes Ca2+ Dysregulation and Adult Cardiomyopathy in Zebrafish

Cardiomyopathies are a group of heterogeneous diseases that affect the muscles of the heart, leading to early morbidity and mortality in young and adults. Genetic forms of cardiomyopathy are caused predominantly by mutations in structural components of the cardiomyocyte sarcomeres, the contractile units of the heart, which includes cardiac Troponin T (TnT). Here, we generated mutations with CRISPR/Cas9 technology in the zebrafish tnnt2a gene, encoding cardiac TnT, at a mutational “hotspot” site to establish a zebrafish model for genetic cardiomyopathies. We found that a heterozygous tnnt2a mutation deleting Arginine at position 94 and Lysine at position 95 of TnT causes progressive cardiac structural changes resulting in heart failure. The cardiac remodeling is presented by an enlarged atrium, decreased ventricle size, increased myocardial stress as well as increased fibrosis. As early as five days post fertilization, larvae carrying the TnT RK94del mutation display diastolic dysfunction and impaired calcium dynamics related to increased Ca²⁺ sensitivity. In conclusion, adult zebrafish with a heterozygous TnT-RK94del mutation develop cardiomyopathy as seen in patients with TnT mutations and therefore represent a promising model to study disease mechanisms and to screen for putative therapeutic compounds.

Prognostic value of fast semi-automated left atrial long-axis strain analysis in hypertrophic cardiomyopathy

BACKGROUND

The prognostic value of left atrial (LA) size and function in hypertrophic cardiomyopathy (HCM) is well recognized, but LA function is difficult to routinely analyze. Fast LA long-axis strain (LA-LAS) analysis is a novel technique to assess LA function on cine cardiovascular magnetic resonance (CMR). We aimed to assess the association between fast LA-LAS and adverse clinical outcomes in patients with HCM.

METHODS

359 HCM patients and 100 healthy controls underwent routine CMR imaging. Fast LA-LAS was analyzed by automatically tracking the length between the midpoint of posterior LA wall and the left atrioventricular junction based on standard 2- and 4-chamber balanced steady-state free precession cine-CMR. Three strain parameters including reservoir strain (εs), conduit strain (εe), and active strain (εa) were assessed. The endpoint was set as composite adverse events including cardiovascular death, resuscitated cardiac arrest, sudden cardiac death aborted by appropriate implantable cardioverter-defibrillator discharge, and hospital admission related to heart failure.

RESULTS

During an average follow-up of 40.9 months, 59 patients (19.7%) reached endpoints. LA strains were correlated with LA diameter, LA volume index (LAVI) and LA empty fraction (LAEF) (all p < 0.05). In the stepwise multivariate Cox regression analysis, εs and εe (hazard ratio, 0.94 and 0.89; p = 0.019 and 0.006, respectively) emerged as independent predictors of the composite adverse events. Fast LA εs and LA εe are stronger prognostic factors than LA size, LAVI and the presence of left ventricular late gadolinium enhancement.

CONCLUSIONS

Fast LA reservoir and conduit strains are independently associated with adverse outcomes in HCM.

Combined Effect of Mediterranean Diet and Aerobic Exercise on Weight Loss and Clinical Status in Obese Symptomatic Patients with Hypertrophic Cardiomyopathy

We evaluated the impact of weight loss (WL) using a Mediterranean diet and mild-to-moderate-intensity aerobic exercise program, on clinical status of obese, symptomatic patients with hypertrophic cardiomyopathy (HCM). Compared with nonresponders, responders showed a significant reduction of left atrial diameter, left atrial volume index (LAVI), E/E'average, pulmonary artery systolic pressure (PASP), and a significant increase in Vo_2max (%) and peak workload. Body mass index changes correlated with reduction in left atrial diameter, LAVI, E/E'average, PASP, and increase of Vo_2max (mL/Kg/min), Vo_2max (%), peak workload. Mediterranean diet and aerobic exercise is associated with clinical-hemodynamic improvement in obese symptomatic HCM patients.

Hypertrophic Cardiomyopathy: Genetic Testing and Risk Stratification

PURPOSE OF REVIEW

Our knowledge of the genetic basis and molecular pathogenesis of hypertrophic cardiomyopathy (HCM) continues to evolve. We describe the genetic basis of HCM, recent advances in genetic testing and the role of genetics in guiding risk stratification and management, both now and in the future.

RECENT FINDINGS

While initially thought to be an exclusively Mendelian disease, we now know there are important HCM sub-groups. A proportion will have sarcomere variants as the cause of their disease, while others will have genetic variants in genes that can give rise to conditions that can mimic HCM. The role of genetics is primarily for cascade genetic testing, though there is emerging evidence of a role for prognosis and patient management. Genetic testing is a useful addition to management. Genotype may play a greater role in risk stratification, management, treatment and prognosis in future, offering improved outcomes for patients and their families with HCM.

Comparative assessment of left atrial volume in healthy cats by two-dimensional and three-dimensional echocardiography

Background

The left atrium (LA) is an important prognostic parameter in cardiac pathologies of cats. Its size is currently measured in one-dimensional methods, while human medicine considers two- and three-dimensional echocardiography as standard. The objectives of this study were to compare monoplane, biplane, triplane and real-time three dimensional echocardiography for volumetric measurement of the left atrium in healthy cats and establish a reference interval for further studies on cats with heart disease. Additionally, the influence of age, sex and weight on left atrial volume (LAV) was tested.

Results

One dimensional monoplane Simpson method of discs (SMOD) in the right parasternal four chamber view (r4) and the left apical 2 chamber view (l2) as well as biplane SMOD had no significant difference for left atrial maximum volume (LAMax). They can be used as equivalent in future studies and one common reference range was set up (1.96 ± 0.54 ml). Those three methods produced significantly higher volumes than triplane echocardiography (RTTPE) and real time three dimensional echocardiography (RT3DE) using TomTec® software. LA volumetry with RTTPE and RT3DE-TomTec™ was more feasible than expected, but low RT3DE image quality was the main reason for excluding patients. Neither age nor weight had an influence on LA volume in healthy cats. Male LAV results were only slightly, but in 2D and RTTPE significantly higher than those of female cats with a range of + 10.46% to + 19.58%.

Conclusions

Monoplane, biplane, triplane and real-time three dimensional echocardiography were feasible for LA volumetry in healthy cats and showed acceptable intra- and interobserver variability. One common LAMax reference range for monoplane r4, l2 and biplane SMOD was set up. Raw data can be used for LA volumes and does not need to be correlated with the cat’s weight or age. Male cats have only slightly but significantly larger atria than females in 2D and RTTPE. Therefore, under reservation, also sex related limit values were defined.

Prevention of sudden cardiac death in hypertrophic cardiomyopathy: Risk assessment using left atrial diameter predicted from left atrial volume

Background

Left atrial diameter (LAd) is included in the European Society for Cardiology's (ESC) risk model for assessment of sudden cardiac death (SCD) risk in hypertrophic cardiomyopathy (HCM), but the recommended measure of LA size is left atrial volume (LAv).

Hypothesis

We hypothesized that LAv could be used instead of LAd in the HCM risk‐SCD model. We aimed to determine the relation between LAd and LAv and to assess the impact of using LAv instead of LAd.

Methods

Echocardiographic measurements of anteroposterior LAd in the parasternal long‐axis window and LAv from Simpson's biplane method of disks were used. The 5‐year risk of SCD by measured LAd and by LAd predicted from LAv were estimated using the ESC risk‐SCD model.

Results

In 205 HCM patients (age 56 ± 14 years, 62% male), the relation between LAd and LAv was linear. Median 5‐year risk of SCD was 2.4% (interquartile range [IQR]: 1.6; 3.8) using measured LAd and 2.4% (IQR: 1.6; 3.7) using predicted LAd. The correlation between the SCD risk assessed by measured vs predicted LAd was excellent (r² = 0.96). Use of predicted LAd resulted in four patients (2%) being recategorized between the moderate and high‐risk categories.

Conclusions

The relation between LAd and LAv was linear with good agreement. On a population level, the correlation between the risk of SCD using measured LAd or LAd predicted from LAv was excellent. On a patient level, using LAd predicted from LAv resulted in the vast majority remaining in the same risk category; however, for a minority of patients, it changed the recommendation.

Echocardiographic Predictors of All-Cause Mortality in Patients with Hypertrophic Cardiomyopathy following Pacemaker Implantation

Objectives

To examine the association between the echocardiographic parameters measured as left atrial diameter (LAD) and left ventricular end-diastolic diameter (LVEDD) and long-term risk of all-cause mortality in adults with hypertrophic cardiomyopathy (HCM) following pacemaker implantation.

Methods

A total of 94 adult patients with HCM who underwent pacemaker implantation from November 2002 to June 2013 in our Arrhythmia Center for symptomatic bradycardia and did not receive an implantable cardiac defibrillator (ICD) or cardiac resynchronization therapy (CRT) during follow-up were retrospectively extracted.

Results

After careful examination of the medical records, we retrospectively evaluated the clinical characteristics of 74 patients with LAD records (58.1 ± 14.9 years) and 76 patients with LVEDD records (57.6 ± 15.2 years). Based on the receiver-operating characteristic (ROC) curve, the values of LAD = 44 mm and LVEDD = 43 mm were identified to predict the all-cause mortality. In the Kaplan–Meier survival, LAD ≥44 mm and LVEDD ≥43 mm were both significantly associated with all-cause mortality (log-rank test P < 0.05). Cox regression analysis indicated that LAD ≥44 mm (HR 3.580; 95% CI = 1.055–12.148; P=0.041) was an independent predictor of all-cause mortality, while LVEDD ≥43 mm was not significantly associated with all-cause mortality. LVOTO was also significantly associated with all-cause mortality (HR = 0.166; 95% CI = 0.036–0.771; P=0.022).

Conclusions

In HCM patients with pacemaker implantation, LAD ≥44 mm was an independent predictor of all-cause mortality.

Left atrial fibrosis correlates with extent of left ventricular myocardial delayed enhancement and left ventricular strain in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is associated with increased left ventricular (LV) mass, decreased myocardial strain, and the presence of LV fibrosis and scar. The relationship between LV scar and fibrosis with left atrial (LA) fibrosis in the setting of HCM has not been examined. The purpose of this study is to demonstrate a correlation between the degree of LA fibrosis and LV parameters in subjects with HCM. Twenty-eight subjects with HCM were imaged on a 1.5T MRI scanner with cine, LV and LA late gadolinium enhancement (LGE) sequences. LA LGE and LA measurements were correlated with LV measurements of volumes, mass, strain, and LGE. Other clinical conditions and medication usage were also examined and evaluated for correlation with LA and LV parameters. LV LGE was identified in 24 (86%) of the cases and LA LGE was identified in all of the cases. Extent of LA fibrosis significantly correlated with percent LV LGE (r = 0.64, p = 0.001), but not with indexed LV mass or maximum wall thickness. Extent of LA fibrosis also moderately correlated with decreased LV global strain (radial, r = - 0.50, p = 0.013; circumferential, r = 0.47, p = 0.02; longitudinal, r = 0.52, p = 0.013). Increased LA systolic volume correlated moderately with LV end diastolic volume (r = 0.50, p = 0.006). Patients on therapy with Renin-Angiotensin-Aldosterone System (RAAS) Inhibition had significantly less LA LGE compared to those without (18.6% vs 10.8%, p = 0.023). LA fibrosis, as measured by LGE, is prevalent in HCM and is correlated with LV LGE. The correlation between LA and LV LGE might suggest either that LA fibrosis is a consequence of LV remodeling, or that LA and LV fibrosis are both manifestations of the same cardiomyopathic process. Further study is warranted to determine the causality of LA scar in this population.

Left Atrial Volume during Stress Is Associated with Increased Risk of Arrhythmias in Patients with Hypertrophic Cardiomyopathy

Introduction:

In patients affected by hypertrophic cardiomyopathy (HCM), left atrial volume index (LAVi) is associated with an increased risk of tachyarrhythmias and major clinical events. To date, the clinical meaning of LAVi measured during exercise (stress LAVi [sLAVi]) has not yet been investigated in HCM. This study sought to evaluate the correlation between LAVi/sLAVi and clinical outcome (risk of arrhythmias and heart failure [HF]) in patients with HCM.

Methods and Results:

We enrolled a total of 51 consecutive patients with HCM (39 men; mean age: 39.41 ± 17.9 years) who underwent standard and stress echocardiography, following a common protocol. During follow-up (median follow-up was 1.82 years), the following composite endpoints were collected: ARRHYT endpoint (atrial fibrillation, paroxysmal supraventricular tachycardia, nonsustained ventricular tachycardia (VT), sustained VT, ventricular fibrillation, syncope of likely cardiogenic nature, and sudden cardiac death) and HF endpoint (worsening of functional class and left ventricular ejection fraction, hospitalization, and death for end-stage HF). Eight patients were lost at follow-up. ARRHYT endpoint occurred in 13 (30.2%) patients (8, 18.6%, supraventricular and 10, 23.2%, ventricular arrhythmias), whereas HF endpoint occurred in 5 (11.6%) patients. sLAVi (mean value of 31.16 ± 10.15 mL/m²) performed better than rLAVi as a predictor of ARRHYT endpoint (Akaike Information Criterion: 48.37 vs. 50.37, if dichotomized according to the median values). A sLAVi value of 30 mL/m² showed a predictive accuracy of 72.1% (C-statistics of 0.7346), with a high negative predictive value (87.5%).

Conclusion:

These findings encourage future studies on sLAVi, as a potential predictor of arrhythmias and adverse outcome in patients with HCM.

Development of and Progression of Overt Heart Failure in Nonobstructive Hypertrophic Cardiomyopathy

Only few studies aimed at identifying predictors of heart failure (HF) in hypertrophic cardiomyopathy (HC) patients. Furthermore, serial echocardiographic analyses are lacking in these patients and little is known about the natural progression of left ventricular (LV) abnormalities and their association with HF development. Aim of this study was to assess the prognostic value of LV global longitudinal strain (GLS) and other clinical and echocardiographic characteristics for the development of HF in patients with nonobstructive HC; furthermore, changes in echocardiographic parameters over time were correlated with HF development. Echocardiography was performed in 236 HC patients (68% men, age: 50 ± 14 years) at their initial visit and during follow-up (6.5(4.1 to 9.8) years). The end point of new HF development or progression to New York Heart Association class III/IV was noted and echocardiographic changes over time were compared among patients with and without HF using linear mixed model analysis. In total, 40 patients reached the HF end point. Multivariable cox regression analysis showed that age (HR 1.04(1.01 to 1.06), p = 0.016), New York Heart Association class (HR 2.30(1.07 to 4.95), p = 0.033), GLS (HR 1.15(1.05 to 1.22), p = 0.001), and left atrial volume (LAVI, HR 2.22(1.10 to 4.50), p = 0.027) were independently associated with the HF end point. Echocardiographic parameters, including GLS and LAVI, remained stable over time in patients without HF end point, but changed significantly in patients who developed HF (group-time interaction, p = 0.042 for GLS and p = 0.027 for LAVI). In conclusion, LV dysfunction is a progressive phenomenon in nonobstructive HC patients which can be detected by repeated echocardiography. Importantly, GLS and LAVI at baseline as well as their changes over time are associated with HF.

Value of Strain Imaging and Maximal Oxygen Consumption in Patients With Hypertrophic Cardiomyopathy

Longitudinal strain (LS) has been shown to be predictive of outcome in hypertrophic cardiomyopathy (HC). Percent predicted peak oxygen uptake (ppVO₂), among other cardiopulmonary exercise testing (CPX) metrics, is a strong predictor of prognosis in HC. However, there has been limited investigation into the combination of LS and CPX metrics. This study sought to determine how LS and parameters of exercise performance contribute to prognosis in HC. One hundred and thirty-one consecutive patients with HC who underwent CPX and stress echocardiography were included. Global, septal, and lateral LS were assessed at rest and stress. Eighty matched individuals were used as controls. Patients were followed for the composite end point of death and worsening heart failure. All absolute LS components were lower in patients with HC than in controls (global 14.3 ± 4.0% vs 18.8 ± 2.2%, p <0.001; septal 11.9 ± 4.9% vs 17.9 ± 2.7%, p <0.001; lateral 16.0 ± 4.7% vs 19.4 ± 3.1%, p = 0.001). Global strain reserve was also reduced in patients with HC (13 ± 5% vs 19 ± 8%, p = 0.002). Over a median follow-up of 56 months (interquartile range 14 to 69), the composite end point occurred in 53 patients. Global LS was predictive of outcome on univariate analysis (0.55 [0.41 to 0.74], p <0.001). When combined with CPX metrics, lateral LS was the only strain variable predictive of outcome along with indexed left atrial volume (LAVI) and ppVO₂. The worst outcomes were observed for patients with lateral LS <16.1%, LAVI >52 ml/m², and ppVO₂ <80%. The combination of lateral LS, LAVI, and ppVO₂ presents a simple model for outcome prediction.

Survival and prognostic factors in hypertrophic cardiomyopathy: a meta-analysis

Hypertrophic cardiomyopathy (HCM) is a clinically and genetically heterogeneous disorder but data on survival rates are still conflicting and have not so far been quantitatively reviewed. The aim of this study is to conduct a meta-analysis of cohort studies to assess pooled survival rates and prognostic factors for survival in patients with HCM. Nineteen studies were included representing 12,146 HCM patients. The pooled 1-, 3-, 5- and 10-year survival rates were 98.0%, 94.3%, 82.2% and 75.0%, respectively. Among patients with HCM, age, NYHA functional class, family history of sudden death (FHSD), syncope, atrial fibrillation, non-sustained ventricular tachycardia (nsVT), maximum left ventricular wall thickness and obstruction were significant prognostic factors for cardiovascular death. For sudden cardiac death, FHSD, nsVT, and obstruction showed significant predictive values. Moreover, estimation of population attributable risk (PAR) suggested that nsVT was the strongest predictor for cardiovascular death (13.02%, 95% CI 3.60–25.91%), while left ventricular outflow tract obstruction/mid-ventricular obstruction (LVO/MVO) was the strongest predictor for all-cause death and sudden cardiac death (10.09%, 95% CI 4.72–20.42% and 16.44%, 95% CI 7.45–31.55%, respectively). These risk factors may thus be useful for identifying HCM patients who might benefit from early diagnosis and therapeutic interventions.

Global Longitudinal Strain and Left Atrial Volume Index Provide Incremental Prognostic Value in Patients With Hypertrophic Cardiomyopathy

BACKGROUND

Current methods for predicting adverse events in patients with hypertrophic cardiomyopathy are still limited. Left ventricular global longitudinal strain (GLS) and left atrial volume index (LAVI) have been recently proposed as novel prognostic factors in several cardiovascular diseases. The objective of this study was to evaluate the prognostic value of GLS and LAVI in patients with hypertrophic cardiomyopathy.

METHODS AND RESULTS

Two-dimensional echocardiography was performed in 427 patients with hypertrophic cardiomyopathy (66% men, age 52±15 years), and LAVI and GLS were assessed. During follow-up, the primary end point of all-cause mortality, heart transplantation, sudden cardiac death, and appropriate implantable cardioverter defibrillator therapy was noted. A total of 103 patients reached the primary end point during a follow-up of 6.7 (interquartile range, 3.3-10.0) years. Multivariable Cox regression analysis revealed GLS and LAVI to be independently associated with the primary end point (hazard ratio GLS, 1.10 [1.03-1.19], P=0.007; hazard ratio LAVI, 4.27 [2.35-7.74], P<0.001) after correcting for other clinical variables. When applying the pre-specified cut-off values of 34 mL/m² for LAVI and -15% for GLS, Kaplan-Meier survival curves showed significant better survival for patients with LAVI <34 mL/m² (P<0.001) and GLS <-15% (P<0.001) as compared with their counterparts. The likelihood ratio test showed a significant incremental prognostic value of LAVI and GLS (P<0.001) as compared with a model with clinical and standard echocardiographic risk factors. The C-statistic for this model increased from 0.68 to 0.73 when adding GLS and LAVI.

CONCLUSIONS

GLS and LAVI are independently associated with adverse outcome in patients with hypertrophic cardiomyopathy and may help to optimize risk stratification in these patients.

Atrial Dilatation Development in Hypertensive Treated Patients: The Campania-Salute Network

BACKGROUND

Left atrial (LA) dilatation is associated with unfavorable outcome in hypertension. However, there are few data on clinical, demographic, and echocardiographic findings correlated with LA dilatation development.

METHODS

From the Campania-Salute Network registry, we identified 5,375 hypertensive patients (52±11 years, 38% women) in normal sinus rhythm, with normal LA diameter (parasternal short-axis <24.0 in women and <25.4mm/m in men), with normal left ventricular (LV) ejection fraction, and with at least 12 months of echocardiographic follow-up. We included in the clinic evaluation type of antihypertensive drugs.

RESULTS

Follow-up duration was of 70±48 months. During follow-up, 647 patients (12%) showed LA dilatation. Patients with incident LA dilatation were older, most likely to be women, more obese, more diabetics, with lower Modification of Diet in Renal Disease, higher total cholesterol, lower uric acid, higher pulse pressure, lower heart rate, higher LV mass, concentric geometry and lower E/A ratio at mitral level, longer E deceleration time, and higher intima-media carotid thickness. They take more drugs, and follow-up was longer (overall P < 0.05). In the Cox analysis, age, female gender, obesity, higher LV mass, LA diameter at baseline, and longer E deceleration time were determinants of LA dilatation. Furthermore, the use of diuretics protected against LA dilatation.

CONCLUSIONS

Our data identify a risk profile for LA dilatation, characterized by older age, female sex, obesity, higher LV mass, and worse diastolic function. In this subgroup of patients, the use of diuretics seems to protect against LA dilatation.

Echocardiographic diagnosis of the different phenotypes of hypertrophic cardiomyopathy

Hypertrophic Cardiomyopathy (HCM) is an inherited cardiovascular disorder of great genetic heterogeneity and has a prevalence of 0.1 – 0.2 % in the general population. Several hundred mutations in more than 27 genes, most of which encode sarcomeric structures, are associated with the HCM phenotype. Then, HCM is an extremely heterogeneous disease and several phenotypes have been described over the years. Originally only two phenotypes were considered, a more common, obstructive type (HOCM, 70 %) and a less common, non-obstructive type (HNCM, 30 %) (Maron BJ, et al. Am J Cardiol 48:418 –28, 1981). Wigle et al. (Circ 92:1680–92, 1995) considered three types of functional phenotypes: subaortic obstruction, midventricular obstruction and cavity obliteration. A leader american working group suggested that HCM should be defined genetically and not morphologically (Maron BJ, et al. Circ 113:1807–16, 2006). The European Society of Cardiology Working Group on Myocardial and Pericardial Diseases recommended otherwise a morphological classification (Elliott P, et al. Eur Heart J 29:270–6, 2008). Echocardiography is still the principal tool for the diagnosis, prognosis and clinical management of HCM. It is well known that the echocardiographic picture may have a clinical and prognostic impact. For this reason, in this article, we summarize the state of the art regarding the echocardiographic pattern of the HCM phenotypes and its impact on clinical course and prognosis.

Functional effects of losartan in hypertrophic cardiomyopathy-a randomised clinical trial

OBJECTIVE

There is a lack of disease-modifying treatments in hypertrophic cardiomyopathy (HCM). The aim of this randomised, placebo-controlled study was to assess if losartan could improve or ameliorate deterioration of cardiac function and exercise capacity.

METHODS

Echocardiography, exercise test and MRI or CT were performed at baseline and after 12 months in 133 patients (52±13 years, 35% female) randomly allocated to losartan (100 mg/day) or placebo.

RESULTS

Losartan had no effect on systolic function compared with placebo (mean difference for left ventricular ejection fraction (LVEF) 0% (95% CI -3% to 4%), p=0.84 or global longitudinal strain 0.7% (95% CI -0.2% to 1.6%), p=0.13). Neither Doppler measures of diastolic function, left atrial volume (mean difference 2 mL/m(2) (95% CI -4 to 8 mL/m(2)) p=0.53) nor exercise capacity (mean difference -0.3 metabolic equivalents (METS) (95% CI -1.0 to 0.3 METS), p=0.28) differed between the treatment groups. At follow-up, there was further progression of disease, with the most prominent impairment being an increase in left atrial volume of 6 mL/m(2) (95% CI 3 to 9 mL/m(2), p<0.0001) in both groups combined. LVEF decreased (mean change -2%, (95% CI -3% to -1%), p=0.037) and 4% of patients had end-stage HCM with a LVEF of less than 50% at the end of the study.

CONCLUSION

Treatment with losartan had no effect on cardiac function or exercise capacity compared with placebo. Losartan fail to improve myocardial performance and failed to alter the progression of the disease. These findings do not support the use of angiotensin II receptor blockers as disease modifiers in adult patients with overt HCM.

TRIAL REGISTRATION NUMBER

NCT01447654-results.

Changes in echocardiographic parameters according to the rate of residual renal function decline in incident peritoneal dialysis patients

Residual renal function (RRF) is associated with left ventricular (LV) hypertrophy as well as all-cause and cardiovascular (CV) mortality in patients with end-stage renal disease. However, no studies have yet examined the serial changes in echocardiographic findings according to the rate of RRF decline in incident dialysis patients. A total of 81 patients who started peritoneal dialysis (PD) between 2005 and 2012 at Yonsei University Health System, Seoul, South Korea, and who underwent baseline and follow-up echocardiography within the first year of PD were recruited. Patients were dichotomized into "faster" and "slower" RRF decline groups according to the median values of RRF decline slope (-1.60 mL/min/y/1.73 m(2)). Baseline RRF and echocardiographic parameters were comparable between the 2 groups. During the first year of PD, there were no significant changes in LV end-diastolic volume index (LVEDVI), left atrial volume index (LAVI), or LV mass index (LVMI) in the "faster" RRT decline group, while these indices decreased in the "slower" RRT decline group. The rate of RRF decline was a significant determinant of 1-year changes in LVEDVI, LAVI, and LVMI. The linear mixed model further confirmed that there were significant differences in the changes in LVEDVI, LAVI, and LVMI between the 2 groups (P = 0.047, 0.048, and 0.001, respectively). During a mean follow-up duration of 31.9 months, 4 (4.9%) patients died. Compared with the "slower" RRF decline group, CV composite (20.29/100 vs 7.18/100 patient-years [PY], P = 0.098), technique failure (18.80/100 vs 4.19/100 PY, P = 0.006), and PD peritonitis (15.73/100 vs 4.95/100 PY, P = 0.064) developed more frequently in patients with "faster" RRF decline rate. On multivariate Cox regression analysis, patients with "faster" RRF decline rate showed 4.82-, 4.44-, and 7.37-fold higher risks, respectively, for each clinical outcome. Preservation of RRF is important for conserving cardiac performance, resulting in an improvement in clinical outcomes of incident PD patients.

Right atrial volume is superior to left atrial volume for prediction of atrial fibrillation recurrence after direct current cardioversion

BACKGROUND

The value of right atrial volume as a predictor for recurrence of atrial fibrillation (AF) after direct current cardioversion (DCCV) is unknown.

METHODS

We sought to compare the performance of right atrial volume indexed to body surface area (RAVI), left atrial diameter, left atrial volume indexed to body surface area (LAVI), and biatrial volume index (BAVI) for the prediction of AF recurrence at 6 months after DCCV. This study included the first 95 consecutive patients from the AF Clinic at a large tertiary care hospital who underwent DCCV and who had an echocardiogram available within 6 months before DCCV. Maximal LAVI, RAVI, and BAVI were determined from the echocardiogram before DCCV. Electrocardiographic and clinical data were acquired at baseline, before cardioversion, and at each clinic visit.

RESULTS

Of the 95 patients (64 male; mean age, 63 ± 12 years), history of systemic hypertension, diabetes mellitus, heart failure, and transient ischemic attack/stroke was present in 60 (63%), 14 (15%), 27 (28%), and 5 (5%) patients, respectively. Mean duration from AF diagnosis to DCCV was 3.5 ± 5.0 years. At 6 months after DCCV, 53 (56%) had reverted to AF. RAVI had superior predictive ability (area under the receiver operator characteristic curve: RAVI, 0.77; left atrial diameter, 0.54; LAVI, 0.64; and BAVI, 0.70). RAVI ≥ 42 mL/m(2) provided the best accuracy for prediction of recurrence (76% accuracy, 71% sensitivity, 83% specificity, 90% positive predictive value, and 56% negative predictive value). Best accuracy for LAVI was ≥ 48 mL/m(2) (70% accuracy, 53% sensitivity, 79% specificity, 85% positive predictive value; 43% negative predictive value).

CONCLUSIONS

RAVI is superior to LAVI for the prediction of AF recurrence at 6 months after DCCV.

Comparison of area-length method by echocardiography versus full-volume quantification by cardiac magnetic resonance imaging for the assessment of left atrial volumes in children, adolescents, and young adults

Left atrial (LA) size is a known predictor of adverse cardiovascular events. Echocardiography is the modality of choice for the evaluation of atrial size; however, cardiac magnetic resonance imaging (cMRI) remains the "gold standard." We sought to calculate atrial volumes using the area-length method by both echocardiography and cMRI and compare them with area-volume quantification by cMRI. Thiry-eight patients (mean age 20 ± 12 years, 71% male) who underwent cMRI and echocardiography between September 2010 and June 2012 were retrospectively identified. The time interval between the two studies was ≤ 6 months. LA volumes by echocardiogram were estimated using the area-length method: LA volume = (0.85 × area(4ch) × area(2ch))/(shortest atrial length). The atrial length and area were measured in standard apical two-chamber and four-chamber planes. Measured values were indexed to body surface area (BSA). CMRI measurements were obtained from prospectively gated steady-state free precession cine stack images obtained in a standard four-chamber plane. LA volumes were calculated using Simpson's method: LA volume = LA area × (slice thickness + gap) per slice. Slice thickness ranged from 5 to 7 mm with contiguous slices of 5 to 7 mm. The values were indexed to BSA. Statistics were summarized using measures of central tendency. LA volumes by echocardiography were significantly less than those by full-volume cMRI quantification. The mean LA volume by echocardiography and full-volume cMRI were 35 ± 14.5 and 42.4 ± 17.2, respectively (p = 0.05). The mean difference between LA volumes obtained by the two methods was 7.4 ± 10.6. LA volume measured by cMRI using the area-length method closely approximated full-volume assessment by cMRI with mean values of 42.9 ± 17.4 versus 42.4 ± 17.2, respectively (p = 0.91). There were no significant differences in the patient characteristics between the two study modalities. LA volumes as measured by echocardiography using the area-length method consistently underestimated the true volume when compared with cMRI. LA volumes measured using the area-length method by cMRI is an alternative technique for accurately quantifying chamber size and can be useful in decreasing scan time or when full-volume data sets are incomplete.

Factors predicting long-term mortality in patients with hypertrophic cardiomyopathy

OBJECTIVES

In this study, we aimed to elucidate the factors affecting long-term all-cause mortality in patients with hypertrophic cardiomyopathy (HCM).

METHOD

We retrospectively examined 31 patients (22 males and 9 females) diagnosed with HCM from 1999 to 2013. All subjects had sinus rhythm at the time of evaluation. Four patients had history of paroxysmal atrial fibrillation (PAF). In addition to echocardiographic examination plasma angiotensin-converting enzyme (ACE) activity and gene polymorphism were determined. The variables that were found to be significant in mortality were then included in multivariate analysis.

RESULTS

At the final follow-up examination, 12 patients had died, including 2 due to congestive heart failure and 10 due to sudden cardiac death. Patients with PAF had significantly higher mortality (P = 0.008). Moreover, left ventricular (LV) end-diastolic diameter (P = 0.04), LV systolic diameter (P = 0.001), LV mass index (P = 0.01), and left atrium diameter (P = 0.003) were found to be significantly correlated with mortality. However, no significant correlation was noted between mortality and age, type of HCM (familial/nonfamilial and obstructive/nonobstructive), ACE gene polymorphism, and plasma ACE level. In the multivariate analysis, left atrial (LA) diameter was still significantly associated with mortality. The LA diameter with a cutoff value of 4.1 cm predicted 13-year mortality with a sensitivity of 82% and specificity of 78%.

CONCLUSION

Instead of the ACE genotype and activity, echocardiographic evaluation findings such as LV systolic and diastolic diameters, LV mass index, and particularly LA dimension may predict long-term mortality in patients with HCM. PAF has also significant importance in the long-term mortality in patients with HCM.

Left atrial remodeling and recurrence of congestive heart failure in patients initially diagnosed with heart failure

BACKGROUND

Left atrial volumes (LAVs) have been suggested to represent long-term exposure to elevated pressures. This study examined the recurrence of heart failure (HF) based on LAV in patients initially diagnosed with congestive HF (CHF).

METHODS

This study comprised 77 patients (age, 75 ± 8 years) with well-documented, clinically defined HF, and complete two-dimensional echocardiographic examinations. The echocardiographic examinations were performed on admission and after medical treatment (90 ± 43 days after initial examination). Patients with atrial fibrillation, flail mitral valve, or mitral valve replacement were excluded from this study.

RESULTS

The initial left ventricular ejection fraction (LVEF) was 44 ± 17% and the indexed LAV (LAVI) was 61 ± 22 mL/m(2) . After medical treatment, a decreased LAVI was observed in 38 patients and an increased LAVI (LA remodeling) was observed in 39 patients. With median follow-up periods of 454 days, compared to patients with decreased LAVI, patients with LA remodeling had a significantly higher incidence of CHF recurrence (P = 0.008). Patients with LA remodeling had a CHF-free survival rate of 36 ± 13% vs. 81 ± 9% (those without LA remodeling). A multivariate analysis indicated that, follow-up LV end-systolic volume (P = 0.04), LVEF (P = 0.005) and LAVI (P = 0.04) independently predicted CHF recurrence.

CONCLUSIONS

Patients initially diagnosed with CHF follow divergent courses based on their LAV. LA remodeling after medical treatment can be useful for predicting CHF recurrence during follow-up.

Prognostic value of left atrial volume in patients with dilated cardiomyopathy

BACKGROUND

Increased left atrial (LA) size is a prognostic marker of mortality in the general population. LA size varies considerably in patients with dilated cardiomyopathy (DCM), but its clinical significance has not been widely studied.

OBJECTIVE

To evaluate the long-term prognostic value of LA volume (LAV) in patients with DCM.

METHODS

We prospectively studied patients admitted from January to December 2004 with a diagnosis of DCM, in sinus rhythm. Complete echocardiographic study at rest and after pharmacological stress was performed in all patients. The composite endpoint of mechanical ventricular assistance (MVA), heart transplantation or death during follow-up was assessed by univariate and multivariate analysis using a Cox regression model.

RESULTS

The study population consisted of 35 patients (68.6% male, mean age 52.0) with DCM, 82.9% of non-ischemic etiology. Ejection fraction (EF) at rest was 31.1 ± 9.4%. During follow-up, eight patients died, one was placed on MVA and one underwent transplantation. Univariate Cox analysis showed various potential echocardiographic markers of prognosis in our population, including LA size in M-mode (HR 1.12, CI: 0.99-1.26, p=0.067), LAV (HR 1.03, CI: 1.00-1.07, p=0.046), LAV adjusted for body surface area (HR 1.03, CI: 0.99-1.26, p=0.049), E/A ratio (HR 0.99; CI: 0.99-1.81; p=0.060); E/A >2 (HR 7.00, CI: 1.48-32.43, p=0.014) and mitral E/E' ratio (HR 1.04, CI: 1.00-1.09, p=0.074). The only variable that remained in the multivariate model was LAV, with a cut-off value of 63 ml (HR 7.7, CI: 0.97-60.61, p=0.05).

CONCLUSIONS

LAV was the only echocardiographic determinant of MVA, heart transplantation or death in our population with DCM. The echocardiographic parameters commonly used for risk stratification such as EF, left ventricular end-diastolic diameter and contractile reserve did not show prognostic significance in our study.

Left atrial enlargement and reduced atrial compliance occurs early in Fabry cardiomyopathy

BACKGROUND

Fabry disease is associated with left ventricular hypertrophy (LVH) and myocardial fibrosis. The aim of this study was to evaluate left atrial (LA) size and function using tissue Doppler-derived strain in patients with Fabry disease.

METHODS

Echocardiography was performed in 33 Fabry patients (14 without LVH, 19 with LVH) before commencement of enzyme replacement therapy, and results were compared with those from age-matched and gender-matched controls (n=28 and n=38, respectively). Atrial strain and strain rate were measured from four segments in the apical four-chamber and two-chamber views of the LA, and global values were calculated. Systolic strain, systolic strain rate, early diastolic strain rate, and late diastolic strain rate were measured. Phasic LA volumes and fractions were calculated. Mitral inflow and tissue Doppler E' velocities were used to estimate left ventricular (LV) diastolic function.

RESULTS

LA volume was increased in Fabry patients, even in the absence of LVH. Importantly, diastolic function was normal in this subgroup without LVH, with E' velocities similar to those in controls. LA systolic strain and early diastolic strain rate were selectively reduced in Fabry patients with LVH and reflect reductions in LA and LV relaxation, respectively, consequent to increased LV mass. However, independent of LVH, both Fabry groups had significant reductions in systolic strain rate and increased LA stiffness index.

CONCLUSIONS

Fabry disease is associated with LA enlargement and reduced atrial compliance that occurs before the development of LVH. This suggests that Fabry cardiomyopathy may not only cause ventricular hypertrophy and fibrosis but also alters atrial myocardial properties early in the disease process. Consequently, measurements of LA size and function may be useful in the early diagnosis of Fabry disease, before the development of LVH.