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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

Background Non-invasive measurement of cardiac output (CO) may become an important modality for the treatment of heart failure. Among the several methods proposed, impedance cardiography (ICG) has gained particular attention. There are 2 basic technologies of ICG: thoracic and whole-body ICG whereby the electrodes are applied either to the chest or to the limbs. The present study is aimed to test the effectiveness of the NonInvasive Cardiac System (NICaS), a new ICG device working with a wrist-to-ankle configuration. Methods and Results To evaluate the reliability of NICaS derived CO (NI-CO), 50 CO measurements were taken simultaneously with thermodilution (TD-CO) and modified Fick (Fick-CO) in 35 cardiac patients, with the TD-CO serving as the gold-standard for the evaluation. Overall, 2-tailed Pearson’s correlation and Bland-Altman limits of agreement between NI-CO and TD-CO were r=0.91 and ‐1.06 and 0.68 L/min and between Fick-CO and TD-CO, r=0.80 and ‐1.52 and 0.88 L/min, respectively. Good correlation was observed in patients with loading conditions altered by nitroglycerin and also in patients with moderate valvular diseases. Conclusion Agreement between NI-CO and TD-CO is within the boundaries of the FDA guidelines of bioequivalence. NI-CO is applicable for non-invasive assessment of cardiac function. (Circ J 2006; 70: 1164 ‐ 1168)

Background: Although cardiac output index (CI), stroke volume index (SVI), and total systemic vascular resistance (TSVR) are important hemodynamic parameters for the prognosis of chronic heart failure (CHF), they are difficult to measure in an outpatient setting. Whole body bioimpedance monitoring using a Non-Invasive Cardiac System (NICaS) allows for easy, non-invasive estimation of these parameters. Here, whether NICaS-derived hemodynamic parameters are clinically significant was investigated by relating them to other conventional car diovascular functional indices, and by evaluating their predictive accuracy for CHF readmission. Methods and Results: Study subjects of 68 patients with CHF were enrolled in the study immediately upon discharge from the hospital. NICaS-derived CI, -SVI, and -TSVR values obtained at an outpatient clinic were significantly related with left ventricular ejection fraction (LVEF) measured by echocardiography, serum B-type natriuretic peptide (BNP), and exercise tolerance. During the 100±98 days follow-up, 15 patients were readmitted to our hospital for CHF recurrence. Multivariate analysis indicated that LVEF, NICaS-derived CI, NICaS-derived SVI, and plasma BNP were significant indicators (receiver operating characteristic curve cut-off point, LVEF: 37%, NICaS-derived CI: 2.49 L · min–1 · m–2, NICaS-derived SVI: 27.2 ml/m2, plasma BNP: 344 pg/ml) for readmission. Conclusions: Hemodynamic parameters derived by NICaS are applicable for the non-invasive assessment of cardiac function in outpatient CHF follow up. (Circ J 2009; 73: 1074 – 1079)

Non-invasive measurement of cardiac output (CO) may become an important modality for the treatment of heart failure. Among the several methods proposed, impedance cardiography (ICG) has gained particular attention. There are 2 basic technologies of ICG: thoracic and whole-body ICG whereby the electrodes are applied either to the chest or to the limbs. The present study is aimed to test the effectiveness of the Non-Invasive Cardiac System (NICaS), a new ICG device working with a wrist-to-ankle configuration.To evaluate the reliability of NICaS derived CO (NI-CO), 50 CO measurements were taken simultaneously with thermodilution (TD-CO) and modified Fick (Fick-CO) in 35 cardiac patients, with the TD-CO serving as the gold-standard for the evaluation. Overall, 2-tailed Pearson's correlation and Bland-Altman limits of agreement between NI-CO and TD-CO were r=0.91 and -1.06 and 0.68 L/min and between Fick-CO and TD-CO, r=0.80 and -1.52 and 0.88 L/min, respectively. Good correlation was observed in patients with loading conditions altered by nitroglycerin and also in patients with moderate valvular diseases.Agreement between NI-CO and TD-CO is within the boundaries of the FDA guidelines of bio-equivalence. NI-CO is applicable for non-invasive assessment of cardiac function.

Among percutaneous coronary intervention post procedural complications, renal acute dysfunction due to administration of contrast agent is commonly seen in patients with pre-existing renal impairment, especially with co-existent diabetes mellitus and/or congestive heart failure. Although several strategies have been proposed to ameliorate this condition, their effects are inconsistent. A 66-year-old diabetic man at high risk for this complication underwent three distinct percutaneous coronary intervention procedures. Different strategies were used during each intervention to prevent the development of contrast medium-induced nephropathy. Dramatic renal protection was observed with human atrial natriuretic peptide administration or hemofiltration, whereas saline hydration had no apparent effect.

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.