RESUMO
OBJECTIVE: To compare the values of three different forms of tissue Doppler imaging (TDI) processing in predicting left ventricular (LV) reverse remodelling-namely, tissue velocity, displacement and strain mapping. DESIGN: Standard echocardiography with TDI was performed before and 3 months after cardiac resynchronisation therapy (CRT). SETTING: University teaching hospital. PATIENTS: 55 patients with heart failure who received CRT and were followed up for at least 3 months were recruited. INTERVENTIONS: During off-line analysis, the time to peak systolic velocity in the ejection phase, time to peak positive displacement and time to peak negative strain were measured in the six basal, six mid-segmental model. Parameters of systolic asynchrony derived by velocity, displacement and strain mapping were correlated with percentage reduction in LV end systolic volume (LVESV) and absolute gain in ejection fraction (EF). RESULTS: Among the three TDI processing technologies, all parameters of tissue velocity correlated with LV reverse remodelling (r = -0.49 to r = -0.76, all p < 0.001), but the predictive value was strongest in models with 12 LV segments. For displacement mapping, only the two parameters that included 12 LV segments correlated modestly with reduction in LVESV (r = -0.36, p < 0.05) and gain in EF. However, none of the strain mapping parameters predicted a favourable echocardiographic response. The receiver operating characteristic (ROC) curve areas were higher for parameters of tissue velocity based on 12 LV segments (ROC areas 0.88 and 0.94) than the corresponding areas derived from displacement mapping (ROC areas 0.72 and 0.71). CONCLUSION: Tissue velocity parameters of systolic asynchrony are superior to those of displacement and strain mapping in predicting LV reverse remodelling response after CRT.
Assuntos
Insuficiência Cardíaca/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Remodelação Ventricular/fisiologia , Idoso , Estimulação Cardíaca Artificial , Ecocardiografia Doppler/métodos , Ecocardiografia Doppler/normas , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Masculino , Sensibilidade e EspecificidadeRESUMO
AIM: This study made use of acoustic quantification (AQ) to investigate if left atrial (LA) mechanical function was impaired in patients with diastolic dysfunction, which might not be detected by conventional Doppler echocardiography. METHODS: One hundred and ten patients with coronary artery disease (mean age 65+/-11 years, 80% male) underwent echocardiography prospectively while AQ was performed using harmonic imaging at the apical four-chamber view to evaluate LA function. RESULTS: By Doppler echocardiography, left ventricular (LV) diastolic dysfunction in the form of abnormal relaxation pattern (ARP) was present in 84, pseudonormal (PN) in nine and restrictive filling pattern (RFP) in 10 patients. LA mechanical dysfunction with impaired total fractional area change (FAC) of =20% was present in 17/19 (89%) patients in the RFP/PN group, but was observed in 27/84 (32%) patients with ARP. Despite identical diastolic Doppler indices between patients with ARP with preserved (n=57) and impaired total FAC, the latter group had significantly lower LV ejection fraction (P<0.001), larger LV volumes (P<0.05 and 0.002, respectively), as well as larger LA area (P<0.001) and lower LA peak emptying and filling rates (both P=0.001). In contrast, there was no difference in nearly all of the parameters of LA function, LV systolic function and LV volume between patients with RFP/PN and ARP with FAC =20%. Both active and passive LA pump functions were impaired in patients with RFP/PN or ARP with FAC =20%. CONCLUSION: LA mechanical dysfunction was found to be present in one-third of the patients with ARP of diastolic dysfunction despite a high MV-A. It was also present in almost all the patients with RFP/PN pattern of diastolic dysfunction. Therefore, AQ may provide information on atrial mechanical function complementary to that of Doppler echocardiography.