AimsOptical frequency domain imaging (OFDI) is a recently developed, light-based, high-resolution intravascular imaging technique. Intravascular ultrasound (IVUS) is a widely used, conventional imaging technique for guiding percutaneous coronary intervention (PCI). We aimed to demonstrate the non-inferiority of OFDI-guided PCI compared with IVUS-guided PCI in terms of clinical outcomes.Methods and resultsWe did a prospective, multicentre, randomized (ratio 1:1), active-controlled, non-inferiority study to compare head-to-head OFDI vs. IVUS in patients undergoing PCI with a second generation drug-eluting stent. The primary endpoint was target vessel failure defined as a composite of cardiac death, target-vessel related myocardial infarction, and ischaemia-driven target vessel revascularization until 12 months after the PCI. The major secondary endpoint was angiographic binary restenosis at 8 months. We randomly allocated 829 patients to receive OFDI-guided PCI (n = 414) or IVUS-guided PCI (n = 415). Target vessel failure occurred in 21 (5.2%) of 401 patients undergoing OFDI-guided PCI, and 19 (4.9%) of 390 patients undergoing IVUS-guided PCI, demonstrating non-inferiority of OFDI-guided PCI to IVUS-guided PCI (hazard ratio 1.07, upper limit of one-sided 95% confidence interval 1.80; Pnon-inferiority = 0.042). With 89.8% angiographic follow-up, the rate of binary restenosis was comparable between OFDI-guided PCI and IVUS-guided PCI (in-stent: 1.6% vs. 1.6%, P = 1.00; and in-segment: 6.2% vs. 6.0%, P = 1.00).ConclusionThe 12-month clinical outcome in patients undergoing OFDI-guided PCI was non-inferior to that of patients undergoing IVUS-guided PCI. Both OFDI-guided and IVUS-guided PCI yielded excellent angiographic and clinical results, with very low rates of 8-month angiographic binary restenosis and 12-month target vessel failure.Clinical registrationClinicalTrials.gov, number NCT01873027.

There were several differences in local findings between OFDI- and IVUS-guided PCI as expected given the different protocols for stent sizing in the 2 groups. The minimum lumen area at the 8-month follow-up was comparable, suggesting that OFDI- and IVUS-guided PCI are similarly feasible using the current-generation drug-eluting stents. (OPtical frequency domain imaging versus INtravascular ultrasound in percutaneous coronary interventiON; NCT01873222).

We explore the feasibility of coronary calcium subtraction computed tomography angiography (CCTA) in patients with high calcium scores using invasive coronary angiography as the gold standard. Eleven patients with calcium scores of >400 underwent CCTA using a subtraction protocol followed by invasive coronary angiography. In addition to standard reconstructions, subtracted images were obtained using a dedicated subtraction algorithm. A total of 55 calcified segments were evaluated for image quality [using a 4-point scale ranging from 1 (uninterpretable) to 4 (good)] and the presence of significant (≥ 50 %) luminal stenosis. Conventional and subtracted CCTA were compared using quantitative coronary angiography (QCA) as the gold standard. The average image quality of conventional CCTA was 2.5 ± 0.6 versus 3.1 ± 0.6 on subtraction CCTA (P < 0.001). The percentage of segments with a score 1 or 2 was reduced from 41.8 to 12.7 % after coronary calcium subtraction (P = 0.002). On QCA, significant stenosis was observed in 16 segments. The area under the receiver operating characteristics curve to detect ≥ 50 % stenosis on QCA increased from 0.741 [95 % confidence interval (CI) 0.598-0.885] for conventional CCTA to 0.905 (95 % CI 0.791-1.000) for subtraction CCTA (P = 0.003). In patients with extensive calcifications undergoing CCTA, coronary calcium subtraction may improve the evaluation of calcified segments.

Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp igh serum levels of low-density lipoprotein-cholesterol (LDL-C) are a major risk factor for atherosclerotic cardiovascular disease. 1 Controlled lowering of LDL-C levels is important for primary and secondary prevention of coronary artery disease (CAD). 2,3 A previous study showed a significant reduction in coronary plaque volume at blood LDL-C levels <100 mg/dl after statin therapy. 4,5 The Framingham study demonstrated that higher LDL-C was a higher relative risk predictor for coronary events. Furthermore, a subgroup analysis of LDL-C and high-density lipoprotein-cholesterol (HDL-C) levels showed that the ratio was a more precise predictor for the relative risk of cardiac events. 6 Another recent study has shown that the predictive value for a cardiovascular event using LDL-C/HDL-C (L/H) ratio is equivalent to the apolipoprotein (Apo) B/ApoA-1 ratio, a precise marker of lipid metabolism. 7 Moreover, posthoc subanalysis of the Treating to New Targets trial, which investigated the correlation between lipid profile and cardiovascular events after statin use for 3 months, showed that the risk of cardiovascular events was increased as the L/H ratio increased, indicating that this ratio is a strong predictor for cardiovascular events. 8 A recent meta-analysis using intravascular ultrasound (IVUS) for evaluating coronary plaque has demonstrated that an L/H ratio >2.0 was associated with progression, while an L/H ratio ≤2.0 was associated with regression of plaque volume. 9

When completed, the OPINION trial will contribute to define the clinical value of the OFDI guidance in PCI.