Frequency of Lipid-Rich Coronary Plaques in Stable Angina Pectoris versus Acute Coronary Syndrome (from the Lipid Rich Plaque Study).

The multicenter prospective Lipid Rich Plaque (LRP) registry showed that nonculprit (NC) lipid-rich plaques identified by near-infrared spectroscopy (maxLCBI4mm >400) with an intravascular ultrasound plaque burden (PB) >70% and/or minimum lumen area (MLA) <4 mm2 within the maxLCBI4mm segment were more frequently associated with major adverse cardiac events (MACE) within 2 years. The aim of this sub-study was to report the relationship between initial clinical presentation and subsequent NC-MACE. Patients enrolled in the LRP study were stratified post hoc as having a stable angina pectoris or silent ischemia presentation versus acute coronary syndrome, excluding patients presenting with acute ST-elevation myocardial infarction. Among the 1552 patients, 717 presented with stable angina pectoris or silent ischemia. Patients presenting with acute coronary syndrome were more likely to be younger and Black, current smokers, and have less chronic kidney disease. Of the scanned nonculprit vessels, there was no difference between the 2 clinical presentation groups regarding lipidic content, and the rate of lipid-rich plaques (maxLCBI4mm >400) was 31.9% in both groups. Finally, there was no difference in NC-MACE at 2 years' follow-up, although within each group (stable versus acute coronary syndrome), the NC-MACE rate associated with maxLCBI4mm >400 was significantly higher than maxLCBI4mm ≤400 (stable 13.8% vs 6.5%; acute patients 11.6% vs 6.3%, respectively). In conclusion, in patient groups that present with stable angina pectoris or silent ischemia versus acute coronary syndrome, the NC lipidic content was similar, as was NC-MACE, through 2 years of follow-up.

Lipid-rich plaques detected by near-infrared spectroscopy predict coronary events irrespective of age: A Lipid Rich Plaque sub-study.

BACKGROUND AND AIMS: In this Lipid Rich Plaque (LRP) sub-study, 1551 patients undergoing coronary angiography for acute coronary syndromes or stable angina were examined with near-infrared spectroscopy (NIRS) and intravascular ultrasound (IVUS). We aimed to assess the correlation of patient age with the presence of high-risk plaques, defined as maximum 4-mm Lipid Core Burden Index (maxLCBI4mm) >400 and plaque burden >70%, and 2-year incidence of non-culprit major adverse cardiovascular events (NC-MACE). METHODS: The study population was divided into four groups according to age: <50 years (122), 50-64 years (700), 65-74 years (502), and ≥75 years (227). The primary outcome was NC-MACE from index procedure to event or the end of the study. Cox regression and mixed-effects Cox regression models were used to assess the effect of age on the association between LCBI and NC-MACE at the patient and plaque levels. RESULTS: Average maxLCBI4mm and percentage of patients with at least one segment with maxLCBI4mm > 400 were similar across the four age groups at both the patient and coronary segment levels. Having at least one segment with maxLCBI4mm > 400 was strongly associated with NC-MACE, and that association did not differ significantly across age subgroups. Although less common (prevalence of 0.8%-1.3%), a similar trend toward greater NC-MACE rates was seen in patients with plaque burden >70% at the maximum LCBI site across age subgroups. CONCLUSIONS: Lipid-rich plaques were as frequent in older as in younger patients and predicted a higher incidence of NC-MACE over 2-year follow-up irrespective of age.

Identification of patients and plaques vulnerable to future coronary events with near-infrared spectroscopy intravascular ultrasound imaging: a prospective, cohort study.

BACKGROUND: Near-infrared spectroscopy (NIRS) intravascular ultrasound imaging can detect lipid-rich plaques (LRPs). LRPs are associated with acute coronary syndromes or myocardial infarction, which can result in revascularisation or cardiac death. In this study, we aimed to establish the relationship between LRPs detected by NIRS-intravascular ultrasound imaging at unstented sites and subsequent coronary events from new culprit lesions. METHODS: In this prospective, cohort study (LRP), patients from 44 medical centres were enrolled in Italy, Latvia, Netherlands, Slovakia, UK, and the USA. Patients with suspected coronary artery disease who underwent cardiac catheterisation with possible ad hoc percutaneous coronary intervention were eligible to be enrolled. Enrolled patients underwent scanning of non-culprit segments using NIRS-intravascular ultrasound imaging. The study had two hierarchal primary hypotheses, patient and plaque, each testing the association between maximum 4 mm Lipid Core Burden Index (maxLCBI4mm) and non-culprit major adverse cardiovascular events (NC-MACE). Enrolled patients with large LRPs (≥250 maxLCBI4mm) and a randomly selected half of patients with small LRPs (<250 maxLCBI4mm) were followed up for 24 months. This study is registered with ClinicalTrials.gov, NCT02033694. FINDINGS: Between Feb 21, 2014, and March 30, 2016, 1563 patients were enrolled. NIRS-intravascular ultrasound device-related events were seen in six (0·4%) patients. 1271 patients (mean age 64 years, SD 10, 883 [69%] men, 388 [31%]women) with analysable maxLCBI4mm were allocated to follow-up. The 2-year cumulative incidence of NC-MACE was 9% (n=103). Both hierarchical primary hypotheses were met. On a patient level, the unadjusted hazard ratio (HR) for NC-MACE was 1·21 (95% CI 1·09-1·35; p=0·0004) for each 100-unit increase maxLCBI4mm) and adjusted HR 1·18 (1·05-1·32; p=0·0043). In patients with a maxLCBI4mm more than 400, the unadjusted HR for NC-MACE was 2·18 (1·48-3·22; p<0·0001) and adjusted HR was 1·89 (1·26-2·83; p=0·0021). At the plaque level, the unadjusted HR was 1·45 (1·30-1·60; p<0·0001) for each 100-unit increase in maxLCBI4mm. For segments with a maxLCBI4mm more than 400, the unadjusted HR for NC-MACE was 4·22 (2·39-7·45; p<0·0001) and adjusted HR was 3·39 (1·85-6·20; p<0·0001). INTERPRETATION: NIRS imaging of non-obstructive territories in patients undergoing cardiac catheterisation and possible percutaneous coronary intervention was safe and can aid in identifying patients and segments at higher risk for subsequent NC-MACE. NIRS-intravascular ultrasound imaging adds to the armamentarium as the first diagnostic tool able to detect vulnerable patients and plaques in clinical practice. FUNDING: Infraredx.