Noa Bachner-Hinenzon1, Assaf Malka2,3, Yaron Barac4, David Meerkin5, Offir Ertracht6, Shemy Carasso7,8, Rona Shofti3, Marina Leitman9,10, Zvi Vered9,10, Dan Adam11, Ofer Binah2,3. 1. Analyze IT Research Institute, Tuval, Israel. 2. Department of Physiology, Technion, Haifa, Israel. 3. Rappaport Faculty of Medicine, Technion, Haifa, Israel. 4. Department of Cardiothoracic Surgery, Rabin Medical Center, Petah Tikva, Israel. 5. Department of Cardiology, Shaare Zedek Medical Center, Jerusalem, Israel. 6. Eliachar Research Laboratory, Medical Center of the Galilee, Nahariya, Israel. 7. Faculty of Medicine, Bar-Ilan University, Tzfat, Israel. 8. Poriya Medical Center, Lower Galilee, Israel. 9. Department of Cardiology, Assaf Harofeh Medical Center, Zerifin, Israel. 10. Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. 11. Faculty of Biomedical Engineering, Technion, Haifa, Israel.
Abstract
BACKGROUND: Myocardial ischemia causes contractile dysfunction in ischemic, stunned, and tethered regions with larger infarcted zones having a negative prognostic impact on patients' outcomes. To distinguish the infarcted myocardium from the other regions, we investigated the diagnostic potential of circumferential strain (CS) and radial strain (RS) during the acute and chronic stages of myocardial infarction. METHODS: Ten pigs underwent 90-minute occlusion of the left anterior descending artery, followed by reperfusion. Echocardiography was performed at baseline, after 90-minute occlusion, and at 2 hours, 30, and 60 days postreperfusion. CS and RS were measured using speckle tracking echocardiography. Subsequently, the pigs were sacrificed, and histological analysis for infarct size was performed. RESULTS: After 90-minute occlusion, reduced strains were detected for all segments (infarcted anterior wall - baseline: CS: -17.6 ± 5.7%, RS: 54.4 ± 16.9%; 90 min: CS: -10.3 ± 3.0%, RS: 23.3 ± 7.0%; tethered posterior wall - baseline: CS: -18.4 ± 3.5%, RS: 68.7 ± 21.1%; 90 min: CS: -10.7 ± 6.4%, RS: 34.5 ± 14.7%, P < 0.001). However, postsystolic shortening was detected only in the infarcted segments, and the time-to-peak CS was 25% longer (P < 0.05). At 30 and 60 days postreperfusion, time-to-peak CS could only detect large scars in the anterior and anterior-septum walls (P < 0.05), while peak CS also detected smaller scars in the lateral wall (P < 0.05). RS failed to distinguish between normal, stunned/tethered, and infarcted myocardium. CONCLUSIONS: During occlusion and 2 hours postreperfusion, time-to-peak CS could distinguish between infarcted and stunned/tethered myocardial segments, while at 30 and 60 days postreperfusion, peak CS was the best detector of infarction.
BACKGROUND:Myocardial ischemia causes contractile dysfunction in ischemic, stunned, and tethered regions with larger infarcted zones having a negative prognostic impact on patients' outcomes. To distinguish the infarcted myocardium from the other regions, we investigated the diagnostic potential of circumferential strain (CS) and radial strain (RS) during the acute and chronic stages of myocardial infarction. METHODS: Ten pigs underwent 90-minute occlusion of the left anterior descending artery, followed by reperfusion. Echocardiography was performed at baseline, after 90-minute occlusion, and at 2 hours, 30, and 60 days postreperfusion. CS and RS were measured using speckle tracking echocardiography. Subsequently, the pigs were sacrificed, and histological analysis for infarct size was performed. RESULTS: After 90-minute occlusion, reduced strains were detected for all segments (infarcted anterior wall - baseline: CS: -17.6 ± 5.7%, RS: 54.4 ± 16.9%; 90 min: CS: -10.3 ± 3.0%, RS: 23.3 ± 7.0%; tethered posterior wall - baseline: CS: -18.4 ± 3.5%, RS: 68.7 ± 21.1%; 90 min: CS: -10.7 ± 6.4%, RS: 34.5 ± 14.7%, P < 0.001). However, postsystolic shortening was detected only in the infarcted segments, and the time-to-peak CS was 25% longer (P < 0.05). At 30 and 60 days postreperfusion, time-to-peak CS could only detect large scars in the anterior and anterior-septum walls (P < 0.05), while peak CS also detected smaller scars in the lateral wall (P < 0.05). RS failed to distinguish between normal, stunned/tethered, and infarcted myocardium. CONCLUSIONS: During occlusion and 2 hours postreperfusion, time-to-peak CS could distinguish between infarcted and stunned/tethered myocardial segments, while at 30 and 60 days postreperfusion, peak CS was the best detector of infarction.
Authors: William M Torres; Julia Jacobs; Heather Doviak; Shayne C Barlow; Michael R Zile; Tarek Shazly; Francis G Spinale Journal: Am J Physiol Heart Circ Physiol Date: 2018-07-13 Impact factor: 4.733
Authors: D S Mansell; V D Bruno; E Sammut; A Chiribiri; T Johnson; I Khaliulin; D Baz Lopez; H S Gill; K H Fraser; M Murphy; T Krieg; M S Suleiman; S George; R Ascione; A N Cookson Journal: Sci Rep Date: 2021-09-15 Impact factor: 4.379