Roberta Ancona

Atrial reservoir function by strain rate imaging in asymptomatic mitral stenosis: prognostic value at 3 year follow-up

AIMS Assessment of left and right systolic atrial reservoir function in asymptomatic mitral stenosis (MS) by strain and strain rate imaging (SRI) and their prognostic power at 3 year follow-up was the purpose of this study. There is clear indication to treat (by surgery or percutaneous valvotomy) symptomatic patients with MS, whereas for the asymptomatic ones, the question is much debated. So, we need new echocardiographic parameters helpful for the management of asymtomatic patients. Atrial reservoir function by SRI could help in evaluation of these patients. METHODS AND RESULTS Fifty-three asymptomatic patients with MS and 53 healthy controls were evaluated by the standard echo-Doppler study [mitral valve (MV) area, mean gradient, systolic pulmonary pressure, left atrial (LA) width, LA volumes, LA compliance index] and by Doppler myocardial imaging (velocity, strain, and SR of both atria). The endpoint at 3 year follow-up was symptoms, hospitalization for cardiac cause, atrial fibrillation, thrombo-embolic events, valvular surgery, or percutaneous commissurotomy. LA width, volumes, and systolic pulmonary pressure were significantly increased in MS patients (P < 0.001). Atrial myocardial velocities and deformation indices were significantly compromised in MS patients (P < 0.0001). Significant correlation was found between atrial myocardial velocity and MV area (by pressure half-time method: P = 0.019, R = 0.41; by planimetric method: P = 0.016, R = 0.43). Peak systolic LA myocardial strain and SR were significantly correlated with atrial volumes (strain: P = 0.03, R = -0.28; SR: P = 0.0008, R = -0.42), with atrial compliance index (strain: P = 0.04, R = 0.26; SR: P = 0.04, R = 0.16), with atrial ejection fraction (strain: P < 0.0001, R = 0.56; SR: P = 0.03, R = 0.43). At 3 year follow-up, 22 (41%) patients had events. Comparing the MS patients who had events during the 3 year follow-up with those who did not, the former had bigger LA volumes, although these parameters did not reached a significant value, whereas atrial myocardial systolic SR was significantly impaired in patients with events. In multivariate analysis, the best predictor of adverse events was LA peak systolic SR average (P = 0.04; coefficient: 0.113; SE: 0.055; cut-off value of 1.69 s(-1) for LA peak systolic SR average) with a sensitivity of 88%, specificity of 80.6%, area under the receiver operating characteristic curve of 0.852 (SE: 0.048; 95% CI: 0.74-0.93, P = 0.0001). CONCLUSION Atrial myocardial deformation properties, assessed by SRI, are abnormal in asymptomatic patients with rheumatic MS. The degree of this impairment is predictor of events in a 3 year follow-up. SRI could be helpful in decision-making of asymtomatic patients with MS.

Heart rate variability is a weak predictor of sudden death in children and young patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) carries a relatively high risk of sudden death, particularly in young people.1,2 To date, the clinical significance of heart rate variability (HRV) in patients with HCM is still controversial.3,4 Our study aimed to analyse HRV in a relatively large cohort of children and young patients with HCM, and to assess potential correlations with clinical markers of sudden death. In all, 53 patients diagnosed with HCM between the ages of 18 and 40 years and body surface area-matched controls were included in this study. The diagnosis of HCM was based on echocardiographic evidence of increased wall thickness, 2 standard deviations (SD) or more compared with age, sex and body surface area-matched people. Maximal ventricular wall thickness (MWT) was defined as the greatest thickness in any segment and measured as the absolute value and as Z score. At the time of the study, age of patients ranged from 1 to 220 months (mean 75.6 (SD 73.7)). Patients with HCM underwent physical examination, rest electrocardiography, conventional echocardiography, exercise test and 24-h …

Clinical Course and Risk Profile in Adolescents With Idiopathic Dilated Cardiomyopathy

We sought to analyze the prevalence, clinical course, and risk profile of left ventricular systolic dysfunction in adolescents with idiopathic dilated cardiomyopathy. Patients with clinical onset at <13 years (n = 18) or >19 years (n = 14) of age and/or patients followed up for <12 months were excluded. Clinical and biochemical markers were evaluated during 4 +/- 3 years of follow-up to determinate predictors of adverse outcome. A composite end point (hospitalization for worsening heart failure, cardiac transplantation, and death) was investigated. The final cohort consisted of 48 patients (median age 17 years) with idiopathic dilated cardiomyopathy. During follow-up, 11 patients required hospitalization for heart failure (21%) and 6 patients entered the transplantation list (4 underwent orthotopic cardiac transplantation, 8%). A Cox multivariate model evidenced N-terminus pro-brain natriuretic peptide (NT-pro-BNP; odds ratio 1, confidence interval 1 to 1.1, p = 0.001), New York Heart Association (NYHA) classes III to IV (odds ratio 2.5, confidence interval 1 to 5.9, p = 0.04), and electrocardiographic atrial enlargement (odd ratios 6.7, confidence interval 1.8 to 25, p = 0.005) as predictors of adverse events (composite end point) at 60 months. The association of NYHA classes III to IV, electrocardiographic atrial enlargement, and NT-pro-BNP value > or =250 pg/ml (are under the curve 0.88) showed 100% sensitivity, 77% specificity, 62% positive predictive value, and 100% negative predictive value. In conclusion, compared to other clinical, echocardiographic, and biochemical parameters, the combination of advanced NYHA class, electrocardiographic atrial enlargement, and NT-pro-BNP > or =250 pg/ml seem to better predict the risk of adverse events in adolescent with long-term systolic dysfunction.

Potential clinical perspectives of Doppler myocardial imaging and strain rate imaging during stress echocardiography.

Stress echocardiography has become a common non-invasive test in patients with chest pain and known or suspected coronary artery disease, but, as with exercise electrocardiography, it shows several major limitations. Analysis of gray-scale images based on subjective visual interpretation of wall motion and thickening has considerable variability even among experts. Doppler myocardial imaging and strain rate imaging echocardiography provides additional information in comparison with conventional echocardiography. These techniques provide quantification of regional wall motion at rest and during stress. Quantification of both systolic and diastolic myocardial function by either Doppler myocardial imaging or strain rate imaging mapping during dobutamine stress test has been shown to be a feasible, accurate, non-invasive tool that should be considered to be a sensitive alternative to the present echocardiographic and scintigraphic imaging techniques for stress tests. Time consuming off-line analysis of color images is required in the present state of technology. However, these non-invasive techniques are rapidly evolving and expanding. Further refinements in signal processing and quantitative analysis are likely in the near future.

The normal right ventricle in young people: assessment of volumes and myocardial deformation properties by three-dimensional echocardiography and Speckle tracking

Background: Right ventricular (RV) function plays an important role in determining cardiac symptoms in several diseases. It has been demonstrated that the new imaging modality of three-dimensional echocardiography (3DE) is interchangeable to cardiac magnetic resonance in reproducibility and accuracy. Speckle Tracking is a sensitive tool to quantitatively assess regional deformation properties. Purpose: To obtain normal reference ranges for RV volumes, RV EF, by 3DE (TomTec) and RV deformation properties by Speckle Tracking and intra and inter-observer reproducibility. Methods: 60 subjects, 32 males and 28 females, aged 25±7 yrs, without any cardiovascular disease, were included. By E9GE we measured RV maximum and minimum volumes by tracing RV endocardial borders during enddiastolic (largest RV volume) and end-systolic (smallest RV volume) phases, in apical 4-chamber, short-axis, and coronal views. Volumes were indexed for body surface. By Speckle tracking we measured 2D longitudinal systolic RV Strain (S) and Strain rate (SR) in apical 4-chambers view, at level of RV free wall (basal, medium and apical segments). A reproducibility study was performed to compare the intra and inter-observer variability. Results: We have reported references range in young people for volumes and EF (3D RV end-diastolic:33±11ml/mq; end-systolic volume:16±6ml/mq; 3D RVEF 67±8%). RV systolic 2D S values in young people were for apical segment -24,59±4,8%, for medium -29,69±4,78%, for basal -30,1±5,88% and RV systolic 2D SR were for apical -1,44±0,25 S-1, for medium: -1,78±0,37 S-1, for basal:-2±0,4 S-1. Inter and intraobserver variability coefficients were 8% and 7% for 3D volumes and 8% and 4% for S-SR measurements, respectively. Conclusions: The present study provides normal reference values for RV volumes and RVEF by 3DE and normal longitudinal RV deformation values in young people. 3DE is an alternative imaging modality for quantification of RV volumes and EF, showing improved accuracy and lower interobserver and intraobserver variability compared to 2D echocardiography; it overcomes the limitations due to the complex anatomy of the RV.