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Aims Since the intravascular ultrasound (IVUS) cannot detect neointimal layers in the majority of sirolimus-eluting stents (SES) at the chronic phase, it is still controversial to what extent SES remain uncovered. However, optical coherence tomography (OCT) with excellent resolution may be able to detect thinner neointima. Methods and results A total of 34 patients (57 SES) underwent OCT and IVUS evaluations at 6-month follow-up. The thickness of neointima on each SES strut cross-section and strut apposition to the vessel wall was evaluated. By OCT evaluation, the median (25th, 75th percentiles) neointima thickness was 52.5 µm (28.0 µm, 147.6 µm) and the prevalence of struts covered by thin neointima undetectable by IVUS was 64%. The average rate of neointima-covered struts in an individual SES was 89%. Nine SES (16%) showed full coverage by neointima, whereas the remaining stents had partially uncovered strut lesions. Among the 6840 struts visualized by OCT in all of the SES, 79 struts showed malapposition without neointimal coverage, and were frequently observed in the areas of SES overlap. Conclusion At 6 months, most of the SES were covered with thin neointima, but few showed full coverage.

Aims Plasma brain natriuretic peptide (BNP) concentration increases in proportion to heart failure (HF) severity. Although plasma BNP decreases to a certain level by optimal treatment, there is significant heterogeneity in the baseline value among individuals. The underlying mechanism of the steady-state plasma BNP levels remains still controversial. We investigated the hypothesis that myocardial stiffness ( K m) is a major determinant of the plasma BNP level. Methods and results In 19 patients with diastolic HF [DHF; left ventricular ejection fraction (LVEF)≥45%], 18 with systolic HF (SHF; LVEF

ObjectivesThis study evaluated the efficacy of catheter-based transcoronary myocardial hypothermia (CTMH) in pigs with acute myocardial ischemia.BackgroundAlthough it has been suggested that hypothermia therapy can attenuate myocardial necrosis, few applications have been accepted for clinical use.MethodsThis study comprises 2 substudies. In both studies, pigs underwent 60 min of coronary occlusion and 180 min of reperfusion. In study 1, after 15 min of coronary occlusion with an over-the-wire-type balloon (OTWB), pigs in the hypothermia group (H) (n = 13) were directly infused with 4°C saline into the coronary artery through the OTWB wire lumen (2.5 ml/min) for 60 min. Pigs in the normothermia group (N) (n = 15) received the same amount of 36.5°C saline. In study 2, pigs in the hypothermia-reperfusion group (HR) (n = 5) were infused with 4°C saline through the infusion catheter (8 ml/min) for 30 min with a later start (60 min after coronary occlusion), whereas simple reperfusion was used for the reperfusion group (R) (n = 6).ResultsCatheter-based transcoronary myocardial hypothermia was successful in both studies. In study 1, CTMH significantly decreased ventricular arrhythmia and the ratio of necrosis to ischemic risk area (H: 9 ± 2%; N: 36 ± 4%; p < 0.0001) with a significant reduction of enzyme leaks. In study 2, CTMH tended to reduce the ratio of necrosis (HR: 33 ± 2%; R: 45 ± 5%; p = 0.08). In both studies, CTMH significantly suppressed the increase of 8-iso-prostaglandin F2αwhile preserving the coronary flow reserve.ConclusionsCatheter-based transcoronary myocardial hypothermia reduced myocardial necrosis while preserving coronary flow reserve, due, in part, to attenuation of oxidative stress.