Evidencia de miocardiopatía incipiente con strain en la enfermedad de Chagas;
Evidence of Early Cardiomyopathy with Strain in Chagas Disease

Objetivo: investigar rol del Strain bidimensional en Enfermedad de Chagas y en la detección de  miocardiopatía incipiente. Métodos:  Estudio transversal, diciembre 2009/marzo 2011,  93 pacientes enfermedad de Chagas: 45 hombres, edad 46 ± 12, divididos en 3 grupos(G): G1 sin cardiopatía, 40 p (GSCD);  G2 anormal ECG, 17 p;  G3 con miocardiopatía, 36 p. Grupo control 35 sujetos, 19 hombres, edad 40 ± 10. Evaluación Eco-Doppler cardíaco: diámetros VI, área auricular izquierda, fracción de eyección VI (Simpson), Excursión sistólica  plano anillos mitral (ESPAM) y tricuspídeo (ESPAT), Flujograma mitral: ondas E y A, DTE,  relación E/A. Se comparó  Grupo Control y GSCD:  DPT anillos mitral y tricuspídeo: ondas E’, A’, relación E’/A y onda S’;  Strain Longitudinal Pico Sistólico Global (SLPSG) y segmentario (SLPSS) Resultados: El SLPSG presentó buena correlación con ESPAM (r: 0,75)  en  pacientes tomados en conjunto.  El análisis del SLPSS  discriminó 2 o más segmentos anormales (valor inferior -12%) en 10 p del GSCD.  El  subgrupo del GSDC  con segmentos anormales  mostró inferior SLPSG  (-19.78 %  vs - 22.28 %  p 0,09), menor valor E’/A’ en el DPT mitral (1.23 ± .59; p 0,021) y  tricuspídeo (0.73 ± .3; p 0,019), con inversión de la relación E’/A’ del anillo tricuspídeo, respecto resto del grupo (n= 30 p). Conclusiones: En enfermedad de Chagas el SLPSG correlacionó con ESPAM, y permitió discriminar en GSCD una subpoblación con segmentos anormales de Strain Longitudinal y  valores inferiores de SLPSG asociados a disfunción diastólica biventricular por DPT.  Su implicancia clínica requiere seguimiento longitudinal.

Background: In Chagas’ disease, cardiomyopathy is the most severe affection produced by this parasitic disease; its slow progressionhas led to several investigations in search of parameters capable of detecting incipient myocardial damage. Currently, the incorporationof strain by speckle tracking echocardiography opens a new horizon.Objective: The aim of this study was to investigate the role of two-dimensional echocardiography in Chagas disease and in the detectionof incipient cardiomyopathy.Methods: A cross-sectional study was performed between December 2009 and March 2011, including 93 patients with Chagasdisease. Forty-five patients were men and mean age was 46±12 years. The patients were divided into three groups (G): G1 (n=40)without demonstrable heart disease), G2 (n=17) with abnormal electrocardiogram and G3 (n=36) with cardiomyopathy. A controlgroup consisted of 35 subjects; 19 were men and mean age was 40±10 years. Doppler echocardiography was performed to evaluateleft ventricular diameters, left atrial area, left ventricular ejection fraction (Simpson), mitral annular plane systolic excursion andtricuspid annular plane systolic excursion. Mitral inflow pattern evaluated E wave, A wave, mitral E wave deceleration time and E/Aratio. Pulsed tissue Doppler imaging was used to measure and compare velocities at the lateral mitral annulus and tricuspid annulus(E’ wave, A’ wave, E’/A’ ratio and S’ wave) and global and segmental longitudinal peak systolic strain.Results: Global longitudinal peak systolic strain correlated with mitral annular plane systolic excursion (r: 0.75) in the pool of patientswith Chagas disease. Segmental longitudinal peak systolic strain differentiated two or more abnormal segments (value below-12%) in 10 patients of the group without demonstrable heart disease. This subgroup (n=10) had lower values of global longitudinalpeak systolic strain (-19.78% vs. -22.28%; p=0.009), lower E’/A’ ratio in the mitral annulus (1.23±0.59; p=0.021) and tricuspid annulus(0.73±0.3; p=0.019), with inverted E’/A’ ratio in the tricuspid annulus compared with the rest of the group (n=30).Conclusions: Global longitudinal peak systolic strain correlated with mitral annular plane systolic excursion. Segmental longitudinalpeak systolic strain differentiated a subpopulation in the group without demonstrable heart disease with abnormal segments,low values of global longitudinal peak systolic strain and biventricular diastolic dysfunction by pulsed tissue Doppler imaging. Theclinical value of this finding requires longitudinal follow-up.