Abstract 701: Novel Echocardiographic Speckle Tracking Methods for Diagnosing Constrictive Pericarditis -The Significance of Longitudinal Strain Impairment in the Left Ventricular Free Wall Preserving Transverse Strain
Constrictive pericarditis (CP) is caused by a thickened, inflamed, adherent, or calcific pericardium that limits myocardial free wall motion without systolic radial ventricular asynergy. Echocardiographic speckle tracking can calculate different directional strains. We hypothesized that longitudinal strains of myocardial free wall might reduce without the reduction of transverse strain of that in CP because epicardial abnormlity could affect the wall motion toward the longitudinal direction more than the transverse direction. Consecutive 7 patients with CP (CP group: 67 ± 16 years) and 15 healthy volunteers (normal group: 29 ± 6 years) were enrolled to this study. We calculated transverse and longitudinal strain of the septal and lateral walls in the four chamber view and compared the ratio of septal and lateral wall strain (SL ratio) between CP and normal control. The parmetric transverse and longitudinal images were also compared between them. We assessed the longitudinal change of those paremeters in four patients underwent surgical treatment. There was no significant between SL ratios of transverse strain in CP and normal group (1.16 ± 0.22 and 1.04 ± 0.18, N.S.). The SL ratio of longitudinal strain in CP group was significantly higher than that in normal group (3.9 ± 1.42 and 0.91 ± 0.06, p = 0.0002). A cut off value of 1.1–2.0 in SL ratio of longitudinal strain discriminated CP from normal with a sensitivity of 100%, specificity of 100%, and predictive accuracy of 100%. In patients with CP underwent surgical treatment, the SL ratio of longitudinal strain decreased from 3.93 ± 1.92 to 1.25 ± 0.17 significantly (p=0.02) although the SL ratio of transeverse strain did not change significantly. Although the transeverse parametric images in CP group were no significant abnormalities, the longitudinal parametric images in CP disclosed the impaired strain color images in the lateral wall. Novel echocardiographic speckle tracking methods disclosed that the impairment of longitudinal strain in the lateral wall preserving transverse strain in patients with CP and could be useful for diagnosing CP and evaluating the effect of the surgical treatment.