Background: Previous studies showed different dyssynchrony patterns between ischemic and normal myocardium at early post-stress using Tl-201 gated SPECT myocardial perfusion imaging (MPI). The aim of this study was to assess the relation of stress-induced dyssynchrony and the extent of angiographic coronary artery disease (CAD).
Methods and results: The MPI images of 144 patients were retrospectively analyzed. With ≥70% stenosis as the criteria of CAD, 57 had no CAD, 32 had 1-vessel disease, 36 had 2-vessel disease, and 19 had 3-vessel disease, respectively. LV global and territorial dyssynchrony parameters were measured by the phase analysis from stress/rest Tl-201 SPECT MPI and compared between stress and rest among the patient groups. The patients with multi-vessel CAD had significantly more global dyssynchrony than the patients without ≥70% stenosis at stress. The patients with multi-vessel CAD showed significantly more global and territorial dyssynchrony on stress images than on rest. More patients with 3-vessel CAD were correctly classified as multi-vessel disease, when combining both visual interpretation and dyssynchrony assessment.
Conclusion: The patients with multi-vessel CAD had significantly more global and territorial dyssynchrony at early post-stress than at rest. Such quantitative measures of myocardial stunning may assist in the diagnosis of multi-vessel CAD.