Prevalence of papillary muscle hypertrophy in fabry disease.

BACKGROUND AND AIMS: Fabry disease (FD) is an X-linked genetic lysosomal disease, in which a deficit in the alpha-galactosidase A enzyme results in lysosomal build-up of globotriaosylceramide in several organs, causing cardiac, renal and cerebrovascular complications. The aim of this study was to assess the prevalence of papillary muscle hypertrophy (PMH) in patients with FD. METHODS: A group of 63 patients with FD and a positive genetic diagnosis were studied and were divided into two groups: one included 24 patients with FD and LVH and another group included 39 patients with FD and without LVH. Papillary muscles were measured from the left parasternal short axis view, defining PMH as a diastolic thickness greater than 11 mm in any diameter. RESULTS: Patients with FD and LVH had a high prevalence of anterolateral PMH (66.6%), and such prevalence was lower for the posteromedial PMH (33.3%). However, patients who had not yet developed LVH had a high prevalence of anterolateral PMH (33.3%). CONCLUSIONS: Patients with FD in the pre-clinical stage (without LVH) have a high prevalence of PMH, especially involving the anterolateral papillary muscle. This finding could be an early marker for the development of LVH, allowing to suspect the disease during its early stages, and begin enzyme replacement therapy in the appropriate patients.

Speckle tracking echocardiography in the indeterminate form of Chagas disease.

BACKGROUND: Chagas disease is one of the most common diseases in Latin-America, and cardiac involvement is a significant cause of death. Assessment of myocardial strain may detect early myocardial damage. OBJECTIVES: To determine differences in longitudinal strain using speckle tracking to assess regional and global left ventricular function in patients with the indeterminate form of Chagas disease, in comparison with a control group. METHODS: This is a retrospective matched case-control study, conducted in a single center. We evaluated 45 adult patients with Chagas disease, diagnosed with 2 serological methods, without evidence of cardiac involvement, who were compared with 45 healthy control subjects, who were sex- and age-matched. All patients underwent Doppler echocardiography and longitudinal strain with speckle tracking. RESULTS: Median age was 59 years, and 60% were female. Echocardiographic parameters were similar in patients with Chagas and control subjects. In patients with Chagas, global strain differed significantly from that of control subjects (-17 vs -20.3, P < .001). Segmental strain showed 7 abnormal segments in patients with Chagas (P < .05). CONCLUSIONS: In patients with the indeterminate form of Chagas disease, global and segmental longitudinal peak systolic strain is reduced compared with healthy subjects, thus suggesting that it could be a sensitive technique to detect early myocardial damage. These findings could provide useful information regarding the pathophysiology of cardiac involvement and understand whether they might have prognostic usefulness or help develop strategies to modify the course and prognosis of patients with Chagas disease. A longitudinal prospective study would be necessary to validate our findings.

Detection of angiographically significant coronary obstruction using resting transthoracic coronary Doppler echocardiography.

BACKGROUND: Transesophageal Doppler echocardiography has shown that significant stenosis can be detected based on the presence of aliasing with color Doppler in the stenotic area. The study aimed to assess the detection of angiographically significant coronary stenosis (ASCS) by analyzing the characteristics and velocities of resting coronary artery flow (RCF) using transthoracic coronary Doppler echocardiography (TCDE). METHODS: TCDE was performed before diagnostic coronary angiography (CA). The following velocities were measured: peak systolic velocity (PSV), peak diastolic velocity (PDV), mean diastolic velocity (MDV), end-diastolic velocity (EDV), and distal to proximal velocity ratios. RESULTS: Twenty-five patients were included, and CA revealed ASCS in 14 patients. With TCDE, the proximal and distal portions of the left anterior descending artery (LAD) could be measured in 84% of cases. Among 12 patients with ASCS in the distal left main coronary artery (LMCA) or proximal or mid LAD, proximal and distal flow could be measured in ten patients. Proximal diastolic velocities were higher in patients with ASCS in the LAD, and a distal MDV/proximal MDV ratio < 0.5 had a 60% sensitivity and a 92% specificity for the detection of ASCS (AUC 0.77, 95% CI 0.56-0.92). For the detection of ASCS limited to the LMCA and/or proximal LAD, the distal MDV/proximal MDV ratio had a sensitivity of 100% and a specificity of 89% (AUC 0.98, 95% CI 0.81-0.99). CONCLUSIONS: Resting TCDE can detect ASCS in the LAD, particularly at the proximal level, analyzing the ratio between distal and proximal flow velocities. These results could not be demonstrated in the RCA and CX arteries.

Speckle tracking echocardiography to assess regional ventricular function in patients with apical hypertrophic cardiomyopathy.

AIM: To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy (HCM). METHODS: We prospectively assessed 20 patients (mean age 53 ± 16 years, range: 18-81 years, 10 were male), with apical HCM. We measured global longitudinal peak systolic strain (GLPSS) in the midwall and endocardium of the left ventricle. RESULTS: The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolic function with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular (LV) systolic function, midwall GLPSS was decreased in all patients, more in the apical (-7.3% ± -8.8%) than in basal segments (-15.5% ± -6.93%), while endocardial GLPPS was significantly greater and reached normal values (apical: -22.8% ± -7.8%, basal: -17.9% ± -7.5%). CONCLUSION: This study shows that two-dimensional strain was decreased mainly confined to the mesocardium, while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM.