Clinical utility of reverse perfusion pattern with 99mTc myocardial stress perfusion scintigraphy

Abstract

Background: Reverse distribution is a pattern that is occasionally observed with 99mTc sestamibi myocardial stress perfusion scintigraphy. The actual cause for this kind of pattern to occur is still under evaluation with no specific aetiology identified. Methods: We retrospectively studied 1195 patients who underwent 99mTc sestamibi myocardial stress perfusion scintigraphy. There was no history of acute myocardial infraction 1 month before the scan; no prior percutaneous transluminal coronary angioplasty was performed in any of these patients. Twenty-seven patients (2.2%) were found to have reverse distribution pattern based on the criteria after ruling out artefacts. Results: Their mean age was 53.5 ± 10.4 years; there were 18 females. Their mean body mass index (BMI) was 27.6 ± 3.4 kg/m2. Six patients had a history of hypertension, 4 patients had a history of diabetes mellitus and 2 patients had both before the scan. Scan findings suggested low probability for coronary artery disease (CAD) in 24 patients and high probability for CAD in three patients. Left anterior descending artery (LAD) territory, posterior descending artery and left circumflex (LCX) artery territory were involved in 22, 8 and 1 patient respectively. The mean time of follow-up was 36.3 ± 4.3 months. None of the patients later had any recurrent episode of chest pain or worsening of symptoms or sentinel events such as death after the scan. Conclusions: Reverse distribution pattern is sometimes observed with 99mTc-MIBI stress MPI. Such a finding has minimal prognostic significance, especially in patients with low and intermediate probability for CAD on imaging.

Keywords

• 99mtc methoxy isobutyl isonitrile
• 99mtc myocardial perfusion scintigraphy
• reverse distribution
• reverse perfusion