Stress echo 2020: the international stress echo study in ischemic and non-ischemic heart disease

Abstract

Background: Stress echocardiography (SE) has an established role in evidence-based guidelines, but recently its breadth and variety of applications have extended well beyond coronary artery disease (CAD). We lack a prospective research study of SE applications, in and beyond CAD, also considering a variety of signs in addition to regional wall motion abnormalities.

Methods: In a prospective, multicenter, international, observational study design, > 100 certified high-volume SE labs (initially from Italy, Brazil, Hungary, and Serbia) will be networked with an organized system of clinical, laboratory and imaging data collection at the time of physical or pharmacological SE, with structured follow-up information. The study is endorsed by the Italian Society of Cardiovascular Echography and organized in 10 subprojects focusing on: contractile reserve for prediction of cardiac resynchronization or medical therapy response; stress B-lines in heart failure; hypertrophic cardiomyopathy; heart failure with preserved ejection fraction; mitral regurgitation after either transcatheter or surgical aortic valve replacement; outdoor SE in extreme physiology; right ventricular contractile reserve in repaired Tetralogy of Fallot; suspected or initial pulmonary arterial hypertension; coronary flow velocity, left ventricular elastance reserve and B-lines in known or suspected CAD; identification of subclinical familial disease in genotype-positive, phenotype- negative healthy relatives of inherited disease (such as hypertrophic cardiomyopathy).

Results: We expect to recruit about 10,000 patients over a 5-year period (2016-2020), with sample sizes ranging from 5,000 for coronary flow velocity/ left ventricular elastance/ B-lines in CAD to around 250 for hypertrophic cardiomyopathy or repaired Tetralogy of Fallot. This data-base will allow to investigate technical questions such as feasibility and reproducibility of various SE parameters and to assess their prognostic value in different clinical scenarios.

Conclusions: The study will create the cultural, informatic and scientific infrastructure connecting high-volume, accredited SE labs, sharing common criteria of indication, execution, reporting and image storage of SE to obtain original safety, feasibility, and outcome data in evidence-poor diagnostic fields, also outside the established core application of SE in CAD based on regional wall motion abnormalities. The study will standardize procedures, validate emerging signs, and integrate the new information with established knowledge, helping to build a next-generation SE lab without inner walls.

Keywords: Effectiveness; Imaging; Prognosis; Stress echocardiography.

Fig. 1

In the box, the contemporary spectrum of patients for whom SE can offer potentially unique diagnostic information: coronary artery disease; heart failure (with either reduced or preserved left ventricular function); hypertrophic cardiomyopathy; valvular heart disease; extreme physiology; adult repaired congenital heart disease; early, at risk, or borderline pulmonary arterial hypertension. For each clinical condition, a different key SE parameter can be used, evaluated at rest (left column) and during stress (right column), maximizing the versatility of the technique. From top to bottom rows, regional wall motion (for ischemia and viability), coronary flow velocity reserve (CFVR), mitral insufficiency, end-systolic volume of the left ventricle (necessary to assess left ventricular elastance), and B-lines (a marker of extravascular lung water). Modified and adapted from ref 4 (Picano and Pellikka [4])

Fig. 2

The computerized case report form for the regional wall motion abnormalities of the SE 2020 study. The grading of the response is reported in tabular (right side, lower panel) and graphic (right side, upper panel) format, with normal values of Wall Motion Score Index in green, mild impairment in yellow, moderate in orange, and severe impairment in red

Fig. 3

The road to SE2020 for the individual stress echo laboratories. The overall recruitment plan for SE2020 targets 10,000 patients by the end of 2020

Fig. 4

The key echocardiographic parameter for each project, around the logo of SE2020. Clockwise: regional wall motion (project 1, but important in all other projects, mainly project 9); end-systolic volume as part of left ventricular elastance assessment (project 2); left ventricular outflow tract gradient (project 3, but also important in project 10); E/e' ratio (project 4); mitral insufficiency (project 5, but also important in project 2); B-lines (essential in project 6, but also important in project 2, 4 and 9); right ventricular function (project 7); pulmonary hemodynamics (project 8 and 10); regional coronary flow velocity reserve (useful in project 9, but also important in projects 2, 3 and 10)