Evaluation of myocardial viability by a secondary delayed 99mTc-MIBI nuclear scanning in ST-elevation myocardial infarction patients with delay in referral and nonviable myocardium in the first scintigraphy: a preliminary cohort study

Nucl Med Commun. 2023 Aug 1;44(8):697-702. doi: 10.1097/MNM.0000000000001716. Epub 2023 Jun 5.

Abstract

Objective: In the management of ST-segment elevation myocardial infarction (STEMI), if the treatment has not been initiated within the first 24 h and the patient no longer exhibits any symptoms, the decision to begin revascularization therapy is based on myocardial viability. If the tissue is nonviable, current guidelines advise against further revascularization therapy; however, collateral vessels represent an alternative source of blood supply and may help the damaged tissue to resume function; though at first, this tissue may not be considered viable. Thus, in patients whose first myocardial perfusion scintigraphy (MPS) revealed nonviable myocardium, a secondary MPS to assess viability may be beneficial and alter the course of treatment strategies.

Methods: This prospective cohort study was conducted on 30 STEMI patients referred to Mazandaran Heart Center. If no myocardial viability was found using 99mTc-MIBI MPS, the patient was referred for a secondary MPS after 3 months.

Results: In total, out of 30 patients, 3 became viable. There was no significant relationship between the viability of different Rentrop classes. Comparison of viability between patients with different numbers of occluded vessels showed no significant relationship. Three patients (17%) among 17 patients with Rentrop class nonzero became viable in the second MPS. Also, among four patients (13.3%) with Rentrop class three, one patient (25%) became viable and among seven patients (23.3%) with Rentrop class one, two patients (28.6%) became viable.

Conclusion: Considering the results of this study, although nonsignificant, this subject requires further investigation to reach a definite conclusion.

MeSH terms

  • Cohort Studies
  • Humans
  • Myocardium
  • Prospective Studies
  • Radionuclide Imaging
  • Referral and Consultation
  • ST Elevation Myocardial Infarction* / diagnostic imaging