Impact of early post-stress 99m Tc sestamibi ECG-gated SPECT myocardial perfusion imaging on the detection of ischemic LV dyssynchrony: an early step in the stunning cascade

• Published in: The international journal of cardiovascular imaging Vol. 37; no. 5; p. 1789
• Main Authors: Cortés, Claudia Mariana, Aramayo G, E Natalia, Barboza, Paula Elizabeth, Crottogini, Alberto, Embon, Mario Alberto
• Format: Journal Article
• Language: English
• Published: United States 01-05-2021
• Subjects: Myocardial perfusion imaging; Ischemia; Intraventricular dyssynchrony; Gated-SPECT
• ISSN: 1875-8312

Transient alterations in ventricular conduction and synchronized cardiac performance have been reported in experimental models of myocardial ischemia. In post-stress
Tc-sestamibi-gated-SPECT myocardial perfusion imaging (MPI), the time elapsed between tracer injection and image acquisition could influence the detection of ischemic left ventricular mechanical dyssynchrony (LVMD). We aimed at evaluating whether early vs. delayed post-stress MPI improve ischemic LVMD detection using the phase analysis parameters standard deviation (SD) and histogram bandwidth (HB) and to assess the correlation between stress-induced changes in SD and HB and other functional parameters. We prospectively studied 32 control subjects (Group-1) and 60 ischemic patients (Group-2). Stress-induced changes were calculated as stress minus rest (Δ). LVMD was defined as post-stress increases of either SD or HB. Group-2 showed higher ΔSD and ΔHB in early than in delayed images: early ΔSD: 1.63 (- 0.37 to 4.83) vs. delayed ΔSD: - 0.39 (- 3.82 to 1.74); early ΔHB: 2.50 (- 4 to 12) vs. ΔHB delayed: - 4 (- 15.75 to 4), all p < 0.01. ΔSD and ΔHB correlated linearly with ΔLV-ejection-fraction (EF) and ΔLV-end systolic-volume (ESV) in early images, all p < 0.01. Early images detected LVMD in more patients than delayed scans (78% vs. 38%; p < 0.01) All patients with LVEF drop in early post-stress evaluation had LVMD. Early post-stress images improve ischemic LVMD detection. Ischemic LVEF and LVESV changes correlate with ΔSD and ΔHB.