Impact of Baseline Imaging of Non-Culprit Coronary Lesions on Adverse Events: Insight From LRP Study.

Background/purpose: Intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) can identify vulnerable coronary atherosclerotic plaques. We aimed to compare the presence or absence of baseline intravascular imaging of non-culprit lesions and their subsequent adverse events.

Methods/materials: We identified patients from the Lipid Rich Plaque (LRP) study who had a non-culprit-lesion adverse event and divided them into 2 cohorts: those with lesions detected with NIRS-IVUS imaging at baseline and those with lesions not imaged at baseline.

Results: Overall, 73 patients had an adverse event (99 coronary segments) during the 24-month follow-up period. Among them, 41 patients (56.2%) had a non-culprit-lesion adverse event related to a coronary segment imaged at baseline, and 32 patients (43.8%) had a non-culprit-lesion adverse event adjudicated to a segment that was not scanned at baseline. Angiographic core laboratory analysis suggested that unscanned lesions were more often in the right coronary artery (~50%); branches of the left coronary artery, i.e., diagonal or left obtuse marginal arteries (~20%); smaller vessels; or more tortuous vessels; and less often in the left anterior descending or distal locations. There was a weak trend for acute severe events (adjudicated myocardial infarction and acute coronary syndrome) in patients with lesions not scanned at baseline (50.0% versus 36.6%, p = 0.250).

Conclusions: In patients with follow-up non-culprit-lesion adverse events, nearly half were not imaged with NIRS-IVUS at baseline. Because events related to non-imaged lesions were at least as severe as events related to imaged lesions, future clinical trials and clinical protocols should be designed to minimize this issue.

Clinical Trial Registration: The Lipid-Rich Plaque Study (LRP), https://clinicaltrials.gov/ct2/show/NCT02033694, NCT02033694.