The value of core lab stress echocardiography interpretations: observations from the ISCHEMIA Trial
Kataoka et al. Cardiovascular Ultrasound
The value of core lab stress echocardiography interpretations: observations from the ISCHEMIA Trial
Akihisa Kataoka 0
Marielle Scherrer-Crosbie 0
Roxy Senior 2
Gilbert Gosselin 1
Denis Phaneuf 7
Gabriela Guzman 6
Gian Perna 5
Alfonso Lara 4
Sasko Kedev 9
Andrea Mortara 8
Mohammad El-Hajjar 3
Leslee J. Shaw 10
Harmony R. Reynolds 11
Michael H. Picard 0
0 Cardiac Ultrasound Laboratory, Massachusetts General Hospital and Harvard Medical School , 55 Fruit Street Yawkey 5E, Boston, MA 02114 , USA
1 Department of Medicine, Montreal Heart Institute , 5000 Belanger St, Montreal QC H1T 1C8 , Canada
2 Department of Cardiovascular Medicine, Division of Cardiology, National Heart and Lung Institute, Imperial College , Sydney Street, London SW3 6NP , UK
3 Division of Cardiology, Internal Medicine, Albany Medical College and Stratton VA Medical Center , 47 New Scotland Ave. MC 44, Albany, NY 12208 , USA
4 Hospital de Especialidades, Centro Medico Nacional 'La Raza', CRC IMSS, Gabriel Mancera 222 Col. del Valle , Benito Juarez, DF 3100 , Mexico
5 Cardiologia Riabilitativa e Preventiva, Ospedali Riuniti of Ancona , via Conca 71, Ancona, Marche 60020 , Italy
6 Departamento de Cardiologia, Hospital Universitario La Paz , Paseo de la Castellana, 261, Madrid 28046 , Spain
7 Department of Cardiology Research, CSSS du Sud de Lanaudiere , 911 Montee des Pionniers, Terrebonne QC J6V 2H2 , Canada
8 Department of Clinical Cardiology and Heart Failure, Policlinico de Monza , Via Amati 111, Monza, MB 20900 , Italy
9 Interventional Cardiology, University Clinic of Cardiology , Vodnjanska 17, Skopje , Macedonia
10 Department of Medicine, Division of Cardiology, Emory University School of Medicine , 1462 Clifton Road, Atlanta, GA 30322 , USA
11 Department of Medicine, Division of Cardiology, New York University Langone Medical Center , 423 East 23rd Street 15150 N, New York, NY 10010 , USA
Background: 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. Methods: Eighty-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. Results: Core 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. Conclusions: While 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 registration: ClinicalTrials.gov NCT01471522
Stress echocardiography; ISCHEMIA Trial; Interpretation variability; Left ventricular myocardial ischemia; Image quality
Background
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
readers to influence its generalizability. In fact, SE
interpretations at individual institutions may be influenced by
local standards and conventions and thus if reviewed at
other institutions might result in different diagnoses
especially in borderline cases [3]. Guidelines have been
developed in order to reduce inter-reader variability [
4
].
However, there is still the potential for less agreement in
SE readings when compared beyond a single institution,
such as when utilized in multicenter studies, and this risk
is a major justification for the use of a centralized core
laboratory interpretation. We utilized SE from sites
participating in an international multicenter trial in order to
examine the concordance between site and core
laboratory SE interpretation and to identify factors which might
influence (...truncated)