The value of technicium-99m sestamibi SPECT scan post coronary angioplasty.

Abstract

BACKGROUND: Evaluation of the increasing rate or referral of patients for SPECT myocardial perfusion imaging after PCI, at the local general hospital has not yet been performed. The problem is that patients are being referred for a Sestamibi scan either too early post intervention where restenosis has not yet occurred or too late post intervention where restenosis has followed. OBJECTIVES: The purpose of the study was to evaluate the value of Tc99M Sestamibi SPECT scans post coronary angioplasty. The correlations were investigated by testing hypothesis. This include: Hypothesis I - The PCI site on angioplasty with the perfusion defect (if any) on SPECT, Hypothesis 2- The timing of the SPECT scan after PCI and the SPECT result in relation to the territory of the original PCI, Hypothesis 3 - The timing of the. SPECT scan after PCI and the SPECT result in relation to territories different from the original site and Hypothesis 4 - The timing of the SPECT scan after PCI and the SPECT result. METHOD: The study is quantitative, non-experimental and retrospective. 155 patients who had undergone a SPECT scan after single vessel PCI from January 2008 till December 2010 were studied. The data was gathered from the Nuclear Medicine Suite and the Cardiac Catheterization Suite. RESULTS: Hypothesis one: There is a significant association between the PCI site and ischemic sites on SPECT (p= 0.02). Hypothesis 2 and 3: There is no significant association between the timing of SPECT after PCI and ischemia in PCI sites and sites remote from the original PCI site (p= 0.15). Hypothesis 4: There is no association between the timing of SPECT after PCI and the level of perfusion in terms of the SSS for both ischemic and non-ischemic patients (p=0.18 & p=0.82). CONCLUSION: Ischemia detected on SPECT in patients post PCI maybe due to restenosis within the same vessel of PCI especially in the LAD, followed by the RCA and LCX respectively. By the passing of time, ischemia is evident within a similar frequency in both patients with ischemia in the same site of PCI and in remote sites. With regards to testing, locally, non-ischemic patients are being scanned within the same frequency of ischemic patients.