The value of core lab stress echocardiography interpretations: observations from the ISCHEMIA Trial.

Akihisa Kataoka,Marielle Scherrer-Crosbie,Alfonso Lara,Gian Perna,Mohammad El-Hajjar,Sasko Kedev,Harmony R Reynolds,Michael H Picard,Denis Phaneuf,Roxy Senior,Gilbert Gosselin,Andrea Mortara,Leslee J Shaw,Gabriela Guzman

doi:10.1186/s12947-015-0043-2

Abstract

BackgroundStress echocardiography (SE) is dependent on subjective interpretations. As a prelude to the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) Trial, potential sites were required to submit two SE, one with moderate or severe left ventricular (LV) myocardial ischemia and one with mild ischemia. We evaluated the concordance of site and core lab interpretations.MethodsEighty-one SE were submitted from 41 international sites. Ischemia was classified by the number of new or worsening segmental LV wall motion abnormalities (WMA): none, mild (1 or 2) or moderate or severe (3 or more) by the sites and the core lab.ResultsCore lab classified 6 SE as no ischemia, 35 mild and 40 moderate or greater. There was agreement between the site and core in 66 of 81 total cases (81 %, weighted kappa coefficient [K] =0.635). Agreement was similar for SE type - 24 of 30 exercise (80 %, K = 0.571) vs. 41 of 49 pharmacologic (84 %, K = 0.685). The agreement between poor or fair image quality (27 of 36 cases, 75 %, K = 0.492) was not as good as for the good or excellent image quality cases (39 of 45 cases, 87 %, K = 0.755). Differences in concordance were noted for degree of ischemia with the majority of discordant interpretations (87 %) occurring in patients with no or mild LV myocardial ischemia.ConclusionsWhile site SE interpretations are largely concordant with core lab interpretations, this appears dependent on image quality and the extent of WMA. Thus core lab interpretations remain important in clinical trials where consistency of interpretation across a range of cases is critical.Trial registrationClinicalTrials.gov NCT01471522

Highlights

Stress echocardiography (SE) is dependent on subjective interpretations
In a prelude to the multicenter ISCHEMIA Trial, we examined the degree of agreement between enrolling site and core lab SE interpretations of cases that were representative of varying degrees of myocardial ischemia
We sought to assess the value of core lab interpretation in a real world experience involving multiple enrolling sites from multiple locations around the world with multiple levels of experience

Summary

Introduction

Stress echocardiography (SE) is dependent on subjective interpretations. As a prelude to the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) Trial, potential sites were required to submit two SE, one with moderate or severe left ventricular (LV) myocardial ischemia and one with mild ischemia. We evaluated the concordance of site and core lab interpretations. Stress echocardiography (SE) is widely used for diagnosis, risk stratification, and prognosis of patients with known or suspected coronary artery disease and has reasonable sensitivity and specificity for clinical decision making [1, 2]. Since SE relies on the subjective assessment of wall motion abnormality (WMA) there is the potential for differences in interpretation by different. Kataoka et al Cardiovascular Ultrasound (2015) 13:47 examine the concordance between site and core laboratory SE interpretation and to identify factors which might influence this concordance

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Discussion

Conclusion