Residual Inflammation and Plaque Progression Long-term Evaluation

Overview

Inflammation drives atherosclerotic plaque rupture triggering most acute coronary syndromes. Despite advances in diagnosis and management of atherosclerosis, patients with myocardial infarction (MI) remain at increased risk of recurrent events. The RIPPLE study aims to examine the relationship between residual coronary inflammation detected by 68Ga-DOTATATE PET in patients treated for MI to long-term plaque progression measured by CT coronary angiography (CTCA). The association between infarct-related myocardial 68Ga-DOTATATE PET and myocardial function and viability will also be assessed.

While vascular inflammation can be detected using 18F-FDG PET, this method lacks inflammatory cell specificity and is unreliable for coronary imaging because of high background signals from the myocardium. Upregulation of somatostatin receptor subtype-2 (SST2) occurs in activated macrophages, offering a novel inflammation imaging target. 68Ga-DOTATATE, an SST2 PET tracer with low myocardial binding, shows promise for imaging coronary inflammation. Having previously demonstrated increased 68Ga-DOTATATE signals in coronary atherosclerotic lesions post-MI, we now aim to study the natural history of residual arterial inflammation in non-culprit arteries and better understand how 68Ga-DOTATATE signals relate to plaque morphology, progression and rupture. Residual infarct-related myocardial inflammation and its association with ischemic myocardial remodelling will also be examined.

Conditions