Abstract 243: Area Strain by 3D Wall Motion Tracking Method is Useful to Detect Adenosine-Induced Myocardial Dysfunction: Comparisons With 99mTc Myocardial Perfusion Scintigraphy
Background: Area strain is a new index of regional myocardial function in three-dimensional (3D) echocardiography and shows % change of area in endocardial layer. The character combines longitudinal and circumferential strains. However, it remains unclear whether assessment of area strain is useful to detect myocardial ischemia in patients with ischemic heart disease (IHD).
Purpose: We investigated whether area strain by 3D wall motion tracking method can detect regional adenosine-induced myocardial ischemia.
Methods: We examined 18 patients with suspected IHD who underwent adenocine-stress 99mTc myocardial scintigraphy. During scintigraphy, 3D full volume images were acquired (Artia™, Toshiba) at rest and during adenosine infusion. The values of area strain were obtained in 6 mid wall segments, and the values of strain at end-systole (A) and at the 30% point of diastolic duration (B) were measured. The diastolic index (DI) was determined as (A−B)/A ×100 (%). We assessed the ratio of DI from rest to during hyperemia (DI ratio) to identify adenosine-induced myocardial ischemia, and compared to the findings of scintigraphy.
Results: DI ratio was significantly decreased in ischemic segments compared to non-ischemic segments (0.73±0.39 vs. 6.00±4.04, P<0.05). By ROC curve for identification of myocardial ischemia determined as perfusion abnormality by scintigraphy, the optimal cut off value of DI ratio was 0.495. The area under curve was 0.74, and the sensitivity and specificity were 77.2% and 85.7%, respectively.
Conclusion: The change of diastolic index in area strain by 3D stress echocardiography is useful to detect regional myocardial ischemia in patients with IHD.