Use of 99mTc-sestamibi gated SPECT to assess the influence of anterograde flow before primary coronary angioplasty on tissue salvage and functional recovery in acute myocardial infarction

Abstract

Abstract.Purpose: Preserved thrombolysis in myocardial infarction (TIMI) flow before percutaneous coronary intervention (PCI) in acute myocardial infarction is related to improved outcome. Gated single-photon emission computed tomography (SPECT) allows the simultaneous assessment of left ventricular perfusion and function. We evaluated the initial risk area and subsequent evolution of perfusion and function according to TIMI flow before successful primary PCI. Methods: In 36 patients, treated with abciximab, primary PCI and stenting, 99m Tc-sestamibi was injected before PCI and gated SPECT acquired thereafter. Gated SPECT was repeated 7 and 30 days later. Perfusion defect, wall motion score index, left ventricular ejection fraction and volumes were examined. Results: Before PCI, 14 patients (group A) showed TIMI flow 2-3 and 22 (group B) TIMI flow 0-1, but no differences in clinical variables, initial risk area, wall motion score, ejection fraction or volumes. Perfusion defect was smaller in group A at 7 (9%±11% vs 19%±14%, p<0.02) and 30 days (7%±7% vs 16%±12%, p<0.02) and the salvage index was higher at 30 days (77%±22% vs 55%±28%, p<0.02). Wall motion score was lower in group A at 30 days (p<0.05). Ejection fraction significantly improved in both groups at 7 and 30 days. Enddiastolic volume showed a trend towards a reduction in group A, whilst it was significantly increased in group B. Conversely, end-systolic volume was significantly decreased in group A but remained unchanged in group B. Conclusion: In the setting of optimal myocardial reperfusion for myocardial infarction, preserved TIMI flow before PCI does not limit the initial risk area but it does improve myocardial salvage and functional recovery.

Effects of a timely therapy with doxycycline on the left ventricular remodeling according to the pre-procedural TIMI flow grade in patients with ST-elevation acute myocardial infarction

“…In agreement with previous studies [1,3,4] and with the latest results obtained by De Luca et al [2] on a large series of over 790 patients treated by primary PCI, we also observed that pre-procedural TIMI flow grade significantly affected enzymatic final infarct size, even when an optimal TIMI flow grade 3 post-PCI was obtained. This ominous relationship between low baseline TIMI flow grade and infarct size has been attributed to different factors resulting from the longer time of ischemia [8], as well as microembolization [7], blood clots and platelet plugs in the microcirculation [9], and a greater myocardial reperfusion injury [10].…”

“…ST-elevation myocardial infarction (STEMI) before primary percutaneous coronary intervention (PCI), which may imply shorter ischemia time, a smaller infarct size [1][2][3], and better left ventricular (LV) function [1,3,4], and patient outcome [5,6]. Conversely, an occluded IRA (TIMI flow grade B1) before primary PCI, which is observed in almost 2/3 of patients with STEMI [2], is associated with increased LV remodeling despite an optimal epicardial mechanical recanalization (post-PCI TIMI flow grade 3) [4].…”

“…A 2D-Echo was performed at baseline and at 6 months, together with a coronary angiography, for the remodeling and IRA patency assessment, respectively. The LV end-diastolic volume index ( [1,3,4], and patient outcome [5,6]. Conversely, an occluded IRA (TIMI flow grade B1) before primary PCI, which is observed in almost 2/3 of patients with STEMI [2], is associated with increased LV remodeling despite an optimal epicardial mechanical recanalization (post-PCI TIMI flow grade 3) [4].…”

“…The LV end-diastolic volume index ( [1,3,4], and patient outcome [5,6]. Conversely, an occluded IRA (TIMI flow grade B1) before primary PCI, which is observed in almost 2/3 of patients with STEMI [2], is associated with increased LV remodeling despite an optimal epicardial mechanical recanalization (post-PCI TIMI flow grade 3) [4]. This ominous relationship between low baseline TIMI flow grade and LV remodeling has been attributed to different factors [7][8][9] including a greater ischemia/reperfusion injury [10].…”

Time-to-treatment and infarct size in STEMI patients undergoing primary angioplasty

“…However, the same group has subsequently observed a significant impact of preprocedural TIMI 3 flow (surrogate marker of ischemic time) on scintigraphic infarct size [28]. In fact, a similar impact of preprocedural TIMI flow was observed also in other studies [29][30][31].…”