Comparison of left atrial size and function in hypertrophic cardiomyopathy and in Fabry disease with left ventricular hypertrophy.

Fabry disease (FD) and hypertrophic cardiomyopathy (HCM) are two diseases with a different pathophysiology, both cause left ventricular hypertrophy (LVH) and myocardial fibrosis. Although remodeling and systolic dysfunction of the left atrium (LA) are associated with atrial fibrillation and stroke in HCM, changes in the size and function of the LA have not been well studied in FD with LVH. The following groups were studied prospectively, and their respective findings compared: 19 patients with non-obstructive HCM (Group I), 20 patients with a diagnosis of Fabry cardiomyopathy (Group II), and 20 normal subjects matched for sex and age (Group III). Left ventricular mass index was measured using Devereux' formula, left atrial volume with Simpson's biplane method and left atrial mechanical function, including strain and strain rate, was measured using the speckle tracking technique. Strain and strain rate of the reservoir were measured during the three phases: reservoir (SR S), passive conduit (SR E) and atrial contraction (SR A). Patients with HCM had a larger left atrial volume than patients with FD (48.16 ± 14.3 mL/m2 vs 38.9 ± 14.9 mL/m2 respectively, P < .001), but in both disorders there was a severe decrease in left atrial function: reservoir strain in the apical four-chamber view: 17.47% in HCM vs 22.5% in FD, P = .24), strain rate in the apical chamber view: SR A: -0.80/seconds in HCM vs -1.04/seconds in FD (P = .88), SR S: 0.69/seconds in HCM vs 0.93 in FD (P = .12), SR E: -0.80 seconds in HCM vs -0.97/seconds in FD (P = .18). In this echocardiographic study we used speckle tracking to assess left atrial mechanical function and showed that FD is associated to an atrial cardiomyopathy, affecting the three phasic functions of the LA. Although in patients with HCM left atrial volume is larger than in patients with FD, both disorders exhibit severe decrease in left atrial function. These findings should be considered, given the potentially serious complications that can occur with the two diseases.

Saccheri MC ，Cianciulli TF ，Challapa Licidio W ，Lax JA ，Beck MA ，Morita LA ，Gagliardi JA ，AADELFA ... -  《-》

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

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. 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. 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. 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.

Boyd AC ，Lo Q ，Devine K ，Tchan MC ，Sillence DO ，Sadick N ，Richards DA ，Thomas L ... -  《-》

Assessment of left atrial function in patients with hypertrophic cardiomyopathy using two-dimensional strain: a comparison with volume-derived values.

Huang J ，Yan ZN ，Rui YF ，Fan L ，Shen D ，Chen DL ... -  《-》

Incremental value of left atrial active function measured by speckle tracking echocardiography in patients with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) impairs left ventricular (LV) diastolic function leading to left atrial (LA) dilatation. Because Doppler echocardiography cannot accurately assess LV diastolic function in hearts with heterogeneous hypertrophy, assessment of LA function might be useful for risk stratification of patients with HCM. This study aimed to elucidate the impact of LA function on outcome in patients with patients. Seventy-six patients with HCM who underwent echocardiographic and cardiac magnetic resonance imaging were retrospectively enrolled. Twenty-six control subjects were also included. Using speckle tracking echocardiography, LA function was divided into active and passive strain indices based on the timing of the second positive peak of LA strain rate that occurred during LV systole. Left atrial strain indices of active and passive function were significantly impaired concomitantly with increased LA volume index in HCM patients compared with controls. During follow-up (2.6 ± 1.7 years), 14 patients with HCM developed cardiac events (heart failure hospitalization or atrial fibrillation). The association of LA active strain with cardiac events was independent of and incremental to clinical and echocardiographic parameters (age, gender, E/e', LV global longitudinal strain, and LA volume index) in sequential models. Cardiac events were more frequent in HCM patients with LA active strain <20.3% than with active strain ≥20.3% (P = .01). Loss of LA active function was associated with increased cardiac events in patients with HCM.

Fujimoto K ，Inoue K ，Saito M ，Higashi H ，Kono T ，Uetani T ，Aono J ，Nagai T ，Nishimura K ，Suzuki J ，Okura T ，Ikeda S ，Nakatani S ，Higaki J ... -  《-》

Systolic and diastolic function assessment in fabry disease patients using speckle-tracking imaging and comparison with conventional echocardiographic measurements.

Fabry cardiomyopathy is characterized by progressive left ventricular hypertrophy (LVH) associated with diastolic dysfunction and is the most common cause of death in Fabry disease (FD). However, LVH is not present in all subjects, particularly early in disease progression and in female patients. Direct assessment of myocardial deformation by strain and strain rate (SR) analysis may be sensitive to detect subclinical Fabry cardiomyopathy independent of the presence of LVH. Systolic (longitudinal, circumferential, and radial systolic strain and SR) and diastolic (SR during isovolumic relaxation [SR(IVR)] and early diastole and strain at peak transmitral E wave) function was assessed in 16 patients with FD using two-dimensional speckle-tracking echocardiography. In addition, mean S' and E' mitral annular velocities by Doppler tissue imaging were measured. Diastolic filling indices, including E/SR(IVR) and E/E' ratios, were calculated. The patients were compared with 24 healthy age-matched and gender-matched controls. All 16 patients with FD had normal left ventricular ejection fractions, and nine patients had LVH. Compared with controls, patients with FD had reduced longitudinal systolic strain (P < .001) and systolic SR (P = .007), while there were no differences in circumferential systolic strain and S'. Diastolic function assessment showed reduced longitudinal early diastolic SR (P = .001), SR(IVR) (P < .001), and E/SR(IVR) (P < .001), while radial and circumferential diastolic function was not affected. Of the conventional diastolic function indices, reductions were seen in E (P = .006), E' (P = .021), and E/E' ratio (P < .001). After correcting for LVH, only SR(IVR) (P < .001) and E/SR(IVR) (P = .025) remained significantly different between patients with FD and controls, with sensitivity of 94% and specificity of 92% for SR(IVR) of 0.235 sec(-1) (area under the receiver operating characteristic curve, 0.953). Strain and SR analysis is useful in identifying patients with FD with reduced myocardial function, with longitudinal systolic strain and diastolic isovolumic SR being superior to the other echocardiographic measurements of myocardial contraction and relaxation and independent of LVH.

Shanks M ，Thompson RB ，Paterson ID ，Putko B ，Khan A ，Chan A ，Becher H ，Oudit GY ... -  《-》