Poster Session - Poster session 2

Abstract

Background: Preliminary studies suggest that myocardial scar can be visualised by transthoracic echocardiography (TTE) using a low mechanical index (MI). Data describing the usefulness of scar imaging by TTE to predict myocardial viability are limited. Purpose: We investigated the association between myocardial scar, as imaged by low MI TTE, and viability as assessed by low-dose dobutamine stress echocardiography (DSE). Methods: We analysed 59 patients who had rest echocardiography including low MI (0.4-0.5) scans and DSEs, performed for myocardial viability between 29/04/2015 to 16/05/2018. Median age was 64 years (interquartile range 57-71), 55 (93%) were male. Left ventricular contrast opacification SonoVue (Braco) was used according to American Society of Echocardiography (ASE) standards (n = 39). Two experienced cardiologists blindly and independently performed 16-segment scar assessment at rest. Viability by DSE was used to represent the ‘gold standard’, from which sensitivity, specificity, negative and positive predictive values of viability assessed by scar at rest were calculated. Results: 42 (71%) of studies had evidence of scar at rest identified by low MI imaging. Presence of scar at rest has a sensitivity of 42%, specificity of 92%, positive and negative predictive values of 82 and 64%, respectively (Table 1). Specificity was higher in non-contrast compared to contrast images, at 97 and 90 %, respectively. The right coronary artery territory had a lower specificity compared to left anterior descending and circumflex territories. Conclusions: Presence of scar at rest has a low sensitivity but high specificity to predict non-viability on low-dose DSE. The presence of scar at rest TTE has the potential to reduce the need for low-dose DSE as these patients are unlikely to have viable myocardium in this region.