Impact of antiplatelet therapy on tissue prolapse at super acute phase after stenting: serial OCT study in acute coronary syndrome patients.

Although drug-eluting stents have improved clinical outcomes, percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remains a challenging procedure in terms of thrombus management. A new-generation P2Y12 receptor inhibitor, prasugrel, provides more rapid and potent antiplatelet action compared with clopidogrel. Prasugrel achieved significant reduction of ischemic events compared with clopidogrel in ACS. The aim of this optical coherence tomography (OCT) study was to evaluate temporal changes in tissue prolapse after stenting under different antiplatelet regimens (aspirin plus prasugrel or clopidogrel) in ACS patients. A total of 119 ACS patients were randomized to either prasugrel or clopidogrel at the time of PCI. OCT analysis was available in 119 patients at baseline (just after stenting), 77 patients at 2 weeks, and 62 patients at 4 months after stenting. Cross-sectional analysis for every 1 mm was performed at in-stent and adjacent reference segment. Tissue prolapse area was calculated by lumen area minus stent area within the stented segment. Baseline patient and procedural characteristics were not different between the prasugrel and clopidogrel groups. Tissue prolapse area was significantly lower in the prasugrel compared with the clopidogrel group after stenting (0.24 ± 0.23 vs. 0.36 ± 0.23 mm2, p = 0.003) and at 2 weeks (0.11 ± 0.13 vs. 0.19 ± 0.16 mm2, p = 0.005). However, there was no significant difference at 4 months. In conclusion, our study suggests prasugrel was effective in reducing tissue prolapse in the super acute phase in ACS patients compared with clopidogrel. However, the effect of tissue prolapse reduction was not different up to 4 months follow-up.

Clinical comparison study between a newly developed optical-based fractional flow reserve device and the conventional fractional flow reserve device.

BACKGROUND: Fractional flow reserve (FFR) measurement is the gold standard for identifying the functional severity of coronary artery disease. Although we can use newly developed pressure wires with optical fibers are now available, their safety and accuracy for FFR measurement are not clear. Therefore, we planned a clinical comparison study between pressure wires with optical fibers and the conventional FFR device. METHODS: We prospectively enrolled 51 patients (51 lesions) with intermediate coronary artery stenosis. For these lesions, FFR measurements with pressure wires with optical fibers were compared with those obtained with a conventional wire. RESULTS: All procedures were successfully completed without any complications. The procedure time with pressure wires with optical fibers and a conventional wire was 6.8 ± 3.0 and 6.9 ± 2.6 minutes (P = 0.89), respectively. There was no significant difference in FFR values between pressure wires with optical fibers and a conventional wire (0.83 ± 0.10 vs. 0.83 ± 0.12, P = 0.66). An excellent correlation was observed between FFR obtained with pressure wires with optical fibers and FFR obtained with a conventional wire (r = 0.81, P < 0.001). The pressure drift before and after FFR measurements was not significantly different between pressure wires with optical fibers and a convention wire (-0.01 ± 0.02 vs. -0.02 ± 0.06, P = 0.42). There was no significant difference in pressure drift defined as >0.03 or <-0.03 between pressure wires with optical fibers and a convention wire (13.7 vs. 17.6%, P = 0.79). CONCLUSION: Excellent correlations were observed between FFR values measured using pressure wires with optical fibers and a conventional wire. Furthermore, measurement of FFR with pressure wires with optical fibers was as well tolerated and reliable as that with a conventional wire.

TangleSolve: topological analysis of site-specific recombination.

UNLABELLED: TangleSolve is a program for analysing site-specific recombination using the tangle model. The program offers an easy-to-use graphical user interface and a visualization tool. Biologists working in topological enzymology can use this program to compute and visualize site-specific recombination mechanisms that accommodate their experimental data. TangleSolve can also prove useful as a teaching aid for mathematical biology and computational molecular biology courses. AVAILABILITY: http://bio.math.berkeley.edu/TangleSolve/