Dissertação
Parâmetros ecocardiográficos indicadores de gravidade na doença falciforme: valor do strain bidimensional
Fecha
2018-05-24Autor
Maria Betânia Solis Resende
Institución
Resumen
Sickle cell disease (SCD) is a multisystem disease caused by a mutation in the globin gene,
leading to the formation of abnormal hemoglobin resulting in haemolytic anemia, vaso
occlusion phenomena and ischemic tissue damage. Early identification of cardiovascular
abnormalities in patients with SCD allows establishing effective therapeutic strategies with
direct impact on morbidity and mortality. Two-dimensional speckle-tracking strain
echocardiography (STE) has been increasingly used for detection of early myocardial
changes in a number of pathophysiological processes of the heart. OBJECTIVES: the study
was designed to examine the prognostic value of STE in predicting clinical outcome in
patients with SCD and to assess echocardiographic parameters that indicate disease
severity. METHODS: A total of 233 SCD adult patients were prospectively enrolled. Patients
performed two-dimensional Doppler echocardiography. Measurements of STE were
quantified and evaluated. The study endpoint was a composite of the following events during
the follow-up: (1) all-cause mortality, (2) three or more acute painful episodes that require
hospitalization in one year, (3) acute chest syndrome and (4) hospitalization for disease
complication. RESULTS: 165 patients (72.7%) carrying hemoglobin (Hb) SS, 56 patients (24.7%) HbSC and 6 patients (2.6%) with sickle cell-beta zero thalassemia (HbS-β0-thal).
The mean age of the patients was 33 ± 11 years (range 18-69 years). During the mean
follow-up of 32 months (ranging from 1.2 to 82.6 months), 69 patients (32%) had reached the
endpoint, including 8 deaths due to SCD (3.6%). The majority of the patients had preserved
systolic function, with LV and LA diameters enlargement. Left atrial volume index and LV
indexed mass were increased. No difference was observed in the parameters of diastolic
function when we compared the groups with and without adverse events during the follow
up. Right ventricle (RV) systolic function was similar in both groups, including RV global
longitudinal strain. LV global longitudinal strain ranged from -12.25 to -25.44 (mean -20.26 ±
2.3). Several clinical, laboratory and echocardiographic variables were tested to evaluate a
possible association with adverse events. In the multivariate analysis, the maximal velocity of
tricuspid regurgitation, LV ejection fraction, LV indexed mass, LA volume index and LV global
longitudinal strain were associated with adverse events. CONCLUSION: Higher LV global
longitudinal strain was an independent predictor of adverse outcome in patients with SCD,
adding incremental prognostic value to the other echocardiographic parameters. Strain
assessment has a potential value for clinical risk stratification in SCD patients.