부산대학교 도서관

Aim: To determine the long-term prognostic accuracy of circumferential and radial myocardial deformation parameters, based on speckle tracking, in predicting worsening of segmental kinetics in ST elevation acute myocardial infarction (STEMI). Methods: Prospective observational study of consecutive patients (pts) with STEMI undergoing primary angioplasty. Echocardiographic study was performed during the first 72h of hospitalization. The Wall Motion Score (WMS) was evaluated by two independent operators with assignment of the final classification by consensus, defining improvement in regional wall motion by a decrease in WMS at least one point. Systolic peak of circumferential strain (S)(SPCS), circumferential strain rate (Sr) (SPCSr), the protodiastolic peak ofcircumferential Sr (DPCSr), the systolic peak of radial S (SPRS), the end systolic radial S and displacement were assessed. The prognostic accuracy inpredicting long term worsening of segmental kinetics was determined by the area under the Receiver Operator Curve (AUC).Results: We studied 42 patients (male: 71%, 60 ± 13 years). The image quality was suitable to study circumferential and radial myocardial deformation in 631segments, of which 36% (N = 225) had abnormalities ofsegmental kinetics in the initial study (hypokinesia, akinesia and dyskinesiain 25.8%, 9, 7% and 0.2% respectively). The proportion of segments with segmental kinetic abnormalities did not differ regarding the ventricular level, although the proportion of akinetic segments was higher in apical segments (p =0.009). There was long-term worsening of wall motion, translated by a WMS increase in at least one point, in 5.7% of segments (N = 36). The risk of long term contractile worsening did not differ in function of the initial WMS. Non akinetic segments in the initial study (WMS <= 2) which become worse had significantly initial less negative values of SPCS, reduced SPRS (p = 0.002)and lower endsystolic radial strain (p <0.001). The accuracy of any of these parameters in predicting worsening of segmental kinetics was moderate, with the SPCS showing the best performance (AUC: 0.65, 95% CI 0.58 to 0.73, p= 0.002).Conclusion: The analysis of circumferential and radial myocardial deformation, by speckle tracking, predicts long term worsening of segmental kinetics in STEMI. PSSC is the parameter with greater accuracy.