Accuracy of global and regional longitudinal strain at peak of dobutamine stress echocardiography to detect significant coronary artery disease

Abstract

Dobutamine stress echocardiography (DSE) is sensitive but subjective diagnostic tool to detect inducible ischemia. Nowadays, speckle tracking allows an objective quantification of regional wall function. We aimed to investigate the feasibility and accuracy of global (GLS) and regional longitudinal strain (RLS) during DSE to detect significant coronary stenosis (SCS). We conducted a prospective observational multicenter study including patients undergoing DSE for suspected SCS. 50 patients with positive DSE underwent coronary angiography. Besides visual regional wall motion score index (WMSI), GLS and RLS were determined at rest and at peak stress by Automated Function Imaging. DSE GLS feasibility was 96%. Among 35 patients with SCS, 12 patients were affected by multivessel disease, 18 had stenosis of left anterior descending artery (LAD), 18 of left circumflex (LCX) and 15 of right coronary artery (RCA). At peak stress, both GLS reduction (p = 0.037) and WMSI worsening (p = 0.04) showed significant agreement with coronary angiography for detecting SCS. When single lesion was considered, peak stress GLS and LAD RLS were lower in the obstructed LAD regions than in normo-perfused territories (17.4 ± 5.5 vs. 20.5 ± 4.4%, p = 0.03; 17.1 ± 7.6 vs. 21.6 ± 5.5%, p < 0.02, respectively). Furthermore, the addition of RLS to regional WMSI was able to improve accuracy in LAD SCS prediction (AUC 0.68, p = 0.037). Conversely, in presence of LCX or RCA SCS, LS was less accurate than WMSI at peak stress. In conclusion, DSE strain analysis is feasible and may improve prediction of LAD SCS, whereas regional WMSI assessment performs better in presence of SCS of LCX and RCA.

Keywords: Anterior myocardial ischemia; Dobutamine stress echocardiography; Regional longitudinal strain; Speckle tracking.

Fig. 1

Circumferential polar plot of the 17 myocardial segments derived by visual wall motion assessment and speckle tracking echocardiography, showing the definition of regions supplied by respective coronary arteries. LAD left anterior descending artery; LCX left circumflex coronary artery; RCA right coronary artery

Fig. 2

Bar graph showing comparison between global and regional WMSI, GLS and RLS according to the perfusion territory supplied by the given SCS at peak stress

Fig. 3

Diagnostic performance of RLS, regional WMSI and their combination for the detection of regional myocardial ischemia in territories supplied by obstructed LAD (a), LCX (b) and RCA (c). AUC area under the curve; CI confidence intervals; LAD left anterior descending artery; LCX left circumflex coronary artery; RCA right coronary artery; rWMSI regional wall motion score index

Fig. 4

Bar graph showing comparison between global and regional WMSI, GLS and RLS according to the perfusion territory supplied by the given SCS at peak stress in patients with previous wall motion abnormalities

Fig. 5

Application of AFI analysis during dobutamine stress echo in patients with severe obstruction of the LAD. Upper panels showing resting apical long-axis view during end-systole (a), and strain analysis performed at the same time (b). Lower panels peak stress apical long-axis view depicting an abnormal response with increased left ventricular end-systolic diameter and hypokinetic contraction of the mid-apical segment of the anterior portion of the septum (c). Strain analysis performed at peak stress showing a clear concomitant RLS reduction in the LAD territory (dotted yellow lines) and GLS reduction compared to baseline values (d)