Early left ventricular dyssynchrony in acute ST elevation myocardial infarction: A gated single photon emission computed tomography study

• Main Authors: Akram Abdelbary, Alaa Abdelhay, M.H. Khedr, M. Emam, Khayri Tohamy
• Format: Article
• Language: English
• Published: Wolters Kluwer 2016-08-01
• Series: Egyptian Journal of Critical Care Medicine
• Subjects: Myocardial perfusion imaging; Phase analysis; Gated SPECT; PCI
• Online Access: http://www.sciencedirect.com/science/article/pii/S209073031630024X

Introduction: The resulting left ventricular (LV) dysfunction in acute STEMI is definitely secondary to loss of myocardial muscle mass (Krumholz et al., 2009; Guerchicoff et al., 2014) but may have an additional component of LV dyssynchrony. Aim: Detection of LV dyssynchrony in acute STEMI patients and its relation to LV dysfunction in these patients. Patients and methods: 60 patients presenting with acute STEMI were injected with 25 mCi of Tc99m SestaMIBI prior to primary PCI. Acquisition was deferred after the procedure within 6 h of injection. Images were analyzed using QGS Cedars Sinai software to measure the histogram bandwidth, standard deviation and entropy using GSPECT phase analysis. The results were compared to 60 patients with negative perfusion scans upon maximal exercise imaged using the same protocol during rest. Results: Our study included a total number of 60 acute STEMI patients, 54 males, mean age 54.8 ± 10.38 years, Compared to 60 controls mean age 50.7 + 20.3 years. Risk factors for CAD were smoking in 41 patients, hypertension in 17, dyslipidemia in 7, diabetes in 15, and positive family history of CAD in 21. 30 patients had acute anterior STEMI and 30 had inferior. LVEDV and LVESV were larger compared to controls; 133.0 ± 88.7 vs. 62.0 ± 19.2 ml and 89.7 ± 82.1 vs. 19.9 ± 12.3 ml respectively, p < 0.001, and lower LVEF 39.0 ± 16.8 vs. 71.1 ± 10.4%, p < 0.001. Histogram bandwidth (BW), standard deviation (SD) and entropy (E) values were significantly higher in patients when compared to controls; 76.2 ± 54.7 vs. 17.8 ± 5.3, 20.7 ± 15.2 vs. 4.1 ± 2.0 and 51.1 ± 18.6 vs. 21.8 ± 7.1 degrees respectively, p < 0.001. BW, SD and E significantly negatively correlated with LVEF in acute STEMI cases; r = −.733, p < 0.001, r = −.75, p < 0.001, and r = −.858, p < 0.001 respectively. Conclusion: LV dyssynchrony may be acquired acutely very early in STEMI and may have a negative impact on LV ejection fraction.