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Factors influencing measurements and accurate evaluation of stent apposition by optical coherence tomography (OCT) are not established.Phantom models of known luminal sizes and lengths were evaluated by OCT under various conditions and measurements were compared with actual values. Stents implanted into phantom models were examined by OCT to validate the measurement point on the stent strut surface for accurate evaluation of stent apposition. Strut thickness was measured at 3 points (midpoint, inner and outer surfaces of the stent shadow). The precision of OCT measurements of lumen diameter and area was satisfactory when the image wire was positioned in the center, but the error and deviation were unsatisfactory when the image wire was positioned eccentrically using a low frame acquisition rate. Longitudinal OCT measurements were close to actual values under all conditions examined. Measurements from the midpoint of the stent shadow to the adjacent vessel wall surface coincided with actual stent thickness.Significant measurement error can occur if the image wire is positioned eccentrically with a lower frame acquisition rate than specified by the manufacturer. To accurately evaluate stent apposition, the stent surface should be measured from the center of the stent reflection.

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)

Background: Sirolimus-eluting stents (SES) have incomplete neointimal coverage at 6-month follow up as determined with optical coherence tomography (OCT). The long-term detailed changes of neointima in SES remains to be clarified. Methods and Results: Serial changes in neointimal coverage of SES from 6 months to 12 months using OCT were examined. Of 21 SES in 13 patients, OCT was used to visualize 2,321 stent struts at 6 months and 2,285 stent struts at 12 months. The frequency of struts without neointimal coverage decreased from 6 months to 12 months (from 10.4 to 5.7%). The frequency of malapposed struts decreased from 6 months to 12 months (from 1.7 to 0.2%). The average thickness of the neointima increased (from 112 ±123 to 120 ±130 μm). The frequency of struts located at the side branch orifice without neointima decreased (from 4 out of 17 (24%) to 0 out of 17 (0%)). Complete coverage with neointima was observed in 14% (3 of 21 SES) at 6 months, and 24% (5 of 21 SES) at 12 months. Conclusions: Additional neointimal coverage was observed between 6 and 12 months, with a small increase in the neointimal thickness. The incidence of complete coverage, however, was still low at 12 months. These findings suggest delayed neointimalization on SES. (Circ J 2009; 73: 1033-1037)

ObjectivesWe sought to evaluate coronary epicardial and intramyocardial resistance, arterial vasomotor function, local inflammatory reaction, and superoxide anion (O2·−) production after overlapping paclitaxel-eluting stent (PES) implantation in a porcine model.BackgroundPES implantation has been shown to elicit coronary vasomotor dysfunction. However, underlying mechanisms remain largely unknown.MethodsNine pigs received overlapping PES and bare-metal stents (BMS) in the coronary arteries, and 3 sham animals were naïve. At 1 month, inflammatory response at the overlapped region was assessed by histopathology and scanning electron microscopy. Endothelial vasomotor function and O2·− at nonstented coronary reference segments were measured by angiography and organ chamber tensiometry, and lucigenin luminometry; vasomotor function of distal resistance arteries was measured by myography.ResultsPaclitaxel-eluting stents showed reduced late lumen loss, but inflammation and luminal inflammatory cell adherence were higher than for BMS (p < 0.001) at overlapped segments. Endothelium-dependent relaxation to substance P was significantly impaired in PES at nonstented coronary reference segments (≥15 mm proximally and distally) and perfusion bed resistance arteries (p < 0.05). In contrast, endothelium-independent relaxation to nitroglycerin and sodium-nitroprusside was similar between groups. Local O2·− production at both proximal and distal nonstented coronary reference segments was elevated for PES when compared with O2·− production in BMS and naïve arteries (p < 0.001).ConclusionsAbnormal endothelium-dependent relaxation at both coronary conduit and resistance arteries was demonstrated after overlapping PES implantation. Profound localized inflammatory reaction, as well as enhanced local oxidative stress, may contribute to vasomotor dysfunction.

Background ; Few studies have investigated the association between biomarkers and in vivo plaque vulnerability in patients with stable coronary artery disease (CAD). Methods ; We examined two or three vessels of 55 stable CAD patients with combined use of virtual histology intravascular ultrasound (VH-IVUS) and optical coherence tomography (OCT), and diagnosed thin-cap fibroatheroma (TCFA). The definition of TCFA was described as follow: necrotic core rich lesion (%necrotic-core>10%) without evident overlying fibrous component and %plaque-volume>40% by VH-IVUS analysis, and the thinnest fibrous-cap thickness Results ; In 55 patients, we could observe 126 vessels (2.29±0.46 vessel/patient) with both modality and we identified 37 TCFA in them. At least one TCFA was identified in 24 patients (43.6%) and not in 31 patients. There were no differences in the clinical characteristics between the two groups. However, a greater number of patients with TCFA had a past history of ACS than those without TCFA (P=0.04). As for laboratory data, there were no differences in lipid and sugar profiles and inflammatory markers, but patients with TCFA had lower plasma adiponectin levels and higher urine- 8-isoprostane/creatinine levels, which is considered as reliable in vivo oxidative stress marker, than patients without TCFA (p=0.0002, P=0.04, respectively). Multivariate logistic regression analysis revealed the most powerful indicative factor of TCFA prevalence in stable CAD was plasma adiponectin levels (P=0.001). The receiver-operating characteristic curve analysis identified plasma adiponectin Conclusion ; Plasma adiponectin levels and urine-8-isoprostane may be one of the tools that help to stratify vulnerable patients into risk categories in patients with stable CAD.

Background: Abnormal endothelium-dependent vasorelaxation of coronary arteries adjacent to drug-eluting stent (DES) implants has been reported and may be associated with late stent thrombosis. However, epicardial resistance vessel vasomotor function in the distal perfusion bed of DES has not been studied. We tested small vessel function 1 mo after coronary artery paclitaxel-eluting stent (PES) implant. Methods: Pigs (n=9) received overlapping bare metal stent (BMS) and PES as well as naïve vessels. One month later, myocardium distal to the stented region, as well as similar location in non-stented vessel (nSV) was harvested. Eighteen epicardial resistance arteries (lumen diameter ~ 250μm) were isolated under a dissecting microscope and mounted on a myograph apparatus. Vasoconstriction (KCl, PGF2α & ET-1), endothelial-dependent relaxation (EDdR) response to substance P (SP), and endothelial-independent relaxation (EDiR) to sodium nitroprosside (SNP) were measured. Results: Angiographic late lumen loss at 1-mo was less for PES than BMS (p=0.002). Epicardial resistance artery relaxation was attenuated in the perfusion distribution of PES, as maximal EDdR in response to SP was 56.0±7.0% compared to vessels isolated from the perfusion distribution of BMS (85.0±7.0%) and non-stented coronary segments (107±2.0%, P=0.034 vs. PES). Maximal EDiR in response to SNP, however, was similar among the groups (90.0±6.0%, PES; 98.0±2.0%, BMS; 123±5.0%, nSV; P=NS respectively). Similarly contraction to endothelin-1 was not affected by stent type (3.95±0.56%, PES; 3.07±0.65%, BMS; 3.01±0.36%, nSV; ratio of contraction ET-1/KCl; P=NS respectively). Conclusions: Epicardial resistance artery endothelial-dependent vasomotor dysfunction is present one month after overlapping coronary PES implant in swine. Derangement of microcirculatory vasomotor function may also be present with DES implant in humans and be associated with a spectrum of adverse clinical sequelae.

Angioscopic analyses have shown the presence of subclinical thrombus in sirolimus-eluting stents (SES) is more common than the clinical incidence of stent thrombosis. However, the determinants and long term significance of subclinical thrombus remain unknown. Thirty five patients (44 stents) who received SES underwent 6 months follow-up optical coherence tomography (OCT). Patients were divided into 2 groups according to the presence of thrombus by OCT. Cross-sectional images were analyzed every 1mm. Stent eccentricity index (SEI; minimum stent diameter divided by maximum stent diameter) was determined in each cross section (CS). To assess the unevenness of neointimal thickness (NIT), a neointimal unevenness score (NUS) was calculated for each CS as maximum NIT in the CS divided by the average NIT of the same CS. Average SEI and NUS were also calculated for each stent. Major adverse cardiac event (MACE) was defined as a composite of death, myocardial infarction, and target vessel revascularization. Eight cases of thrombus were detected by OCT (18%). The thrombus cases were associated with longer stent length, larger numbers of uncovered struts, smaller average SEI, and greater average NUS (Table ). A significant relationship existed between the average SEI and average NUS ( P P =0.005, R=0.47). There was no significant difference in MACE during follow-up (median: 655days) (Thrombus: 0%, Non-thrombus: 7.4%, P=0.43). Based on OCT, longer stents, a larger number of uncovered stent struts, asymmetric stent expansion, and unevenness of NIT may be important determinants of thrombus formation in patients treated with SES. Asymmetric stent expansion may interfere with even neointimal coverage after SES deployment, perhaps a key mechanism for thrombus formation. In this small cohort, the presence of thrombus did not seem to increase the risk of MACE.

The present study was designed to evaluate a novel bioerodible sol-gel film coated paclitaxel-eluting stent (sol-gel-PES, 3 microg per stent) in a porcine coronary artery model.Although current polymer-based PES decrease restenosis, the permanent polymer and bound drug have raised concerns regarding delayed vessel healing and late stent thrombosis.Polymer-based PES (poly-PES, n = 8), sol-gel-PES (n = 15), bare metal (BMS, n = 14), and sol-gel film only (sham, n = 12), stents were implanted in 17 juvenile pigs. Animals were terminated 28 days post-implant for angiographic restudy and complete histopathologic and histomorphometric analyses.Angiographic late loss was equally reduced for both poly-PES and sol-gel-PES (0.51 +/- 0.64 and 0.61 +/- 0.52 mm, respectively) compared to both BMS and sham (0.98 +/- 0.74 and 1.25 +/- 0.72 mm, p0.05). Similarly beneficial results were observed for histomorphometric parameters of neointimal thickness and area, yielding reductions of in-stent stenosis by 43% and 48% for poly-PES, as well as 31% and 37% for sol-gel-PES, vs. BMS and sham, respectively (p0.05). Re-endothelialization was complete in all groups. Although the inflammatory cell infiltration and intramural thrombus scores were no different between poly- and sol-gel-PES, medial necrosis was increased for poly-PES (p0.05 vs. all others).A novel bioerodible sol-gel film coated with low-dose paclitaxel demonstrates less toxicity to the coronary tunica media, while retaining effective inhibition of neointimal formation at 28 days.

Noninvasive methods to derive fractional flow reserve from coronary CT angiography data depend on the accuracy of the luminal boundary extracted from image data. The spatial resolution of coronary CTA data has been considered as a fundamental upper limit on the accuracy and precision of FFRCT, but

Elevated circulating C-reactive protein (CRP)is commonly observed in patients with acute coronary syndrome(ACS), suggesting enhanced inflammation in vulnerable plaques. However, few data are available on the relationship between the levels of CRP and the histological composition of coronary plaque. We investigated the relationship between plasma high sensitive CRP level and coronary plaque component with Virtual Histology intravascular ultrasound (VH-IVUS).Twenty eight patients with ACS and 37 patients with non-ACS were enrolled in the study. Plasma high sensitve CRP levels were measured before catheterization. A total of 125 lesions (ACS; 24 culprit lesions, 30 non-culprit lesions, non-ACS; 34 culprit lesions, 37 non-culprit lesions)underwent IVUS volumetric investigation, and the volume of plaque and media were calculated. Spectral analysis of IVUS radiofrequency data was performed with VH software, and plaque and media were classified into fibrous, fibro-fatty, dense calcium, and necrotic core elements.Although the plasma high sensitive CRP level in patients with ACS was higher than that in those with non-ACS (0.26 +/- 0.2 vs 0.15 +/- 0.17 mg/dl, p0.05), necrotic core volume was not different between the two groups(11.7 +/- 7.3 vs 12.3 +/- 7.2mm3/cm, p = 0.71). There was a positive correlation between high sensitve CRP and necrotic core volume in patients with ACS, not only in culprit lesions (p = 0.0004, r2 = 0.564) but also in non-culprit lesions (p = 0.0008, r2 = 0.473), whereas patients with non-ACS showed no correlations.IVUS spectral analysis revealed that elevated plasma high sensitve CRP level was correlated with necrotic core volume in patients with ACS, both in culprit and non-culprit lesions, suggesting enhanced vascular inflammation.

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.

Technology and techniques of cardiac catheterization to assess the ventricular function have been developed in the recent decades. The approach for assessing function is based on the measurement of cardiac output which depends on preload, afterload and ventricular contractility. Clinical application of Frank-Starling principle is useful for characterizing human heart failure. Conventionally, the isovolumic phase index(peak positive dP/dt) and ejection phase index (ejection fraction) have been applied to evaluate ventricular systolic function. Recently, ventricular diastolic function as well as systolic function can be estimated using ventricular pressure-volume loops obtained by simultaneous measurement of pressure and volume. The slope of end-systolic pressure-volume relation represents a load-independent index of ventricular contractility and assessing ventricular end-diastolic pressure-volume relation can express ventricular passive diastolic compliance for the evaluation of human heart failure.

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.

Background— The neurotrophin (NT) family, including nerve growth factor NT-3 and brain-derived neurotrophic factor (BDNF), has a critical role in the survival, growth, maintenance, and death of central and peripheral neurons. NTs and their receptors are expressed in atherosclerotic lesions; however, their significance in cardiovascular disease remains unclear. Methods and Results— To clarify the role of NTs in the pathogenesis of coronary artery disease, NT plasma levels in the aorta, coronary sinus, and peripheral veins of patients with unstable angina (n=38), stable effort angina (n=45), and non–coronary artery disease (n=24) were examined. In addition, regional expression of BDNF in coronary arteries was examined in autopsy cases and patients with angina pectoris by directional coronary atherectomy. The difference in BDNF levels, but not NT-3, between the coronary sinus and aorta was significantly greater in the unstable angina group compared with the stable effort angina and non–coronary artery disease groups. Immunohistochemical investigations demonstrated BDNF expression in the atheromatous intima and adventitia in atherosclerotic coronary arteries. BDNF expression was enhanced in macrophages and smooth muscle cells in atherosclerotic coronary arteries. Stimulation with recombinant BDNF significantly enhanced NAD(P)H oxidase activity and the generation of reactive oxygen species in cultured human coronary artery smooth muscle cells. Conclusions— BDNF has an important role in atherogenesis and plaque instability via the activation of NAD(P)H oxidase.

Objective— NADH/NADPH oxidase is an important source of reactive oxygen species (ROS) in the vasculature. Recently, we demonstrated that p22 phox , an essential component of this oxidase, was expressed in human coronary arteries and that its expression was enhanced with the progression of atherosclerosis. The present study was undertaken to investigate its functional importance in the pathogenesis of coronary artery disease. For this aim, the expression of p22 phox , the distribution of oxidized low density lipoprotein (LDL), and the generation of ROS in directional coronary atherectomy (DCA) specimens were examined. Methods and Results— DCA specimens were obtained from patients with stable or unstable angina pectoris. The distribution of p22 phox and of oxidized LDL was examined by immunohistochemistry. The generation of superoxide in DCA specimens was assessed by the dihydroethidium method and lucigenin-enhanced chemiluminescence. ROS were closely associated with the distribution of p22 phox and oxidized LDL. Not only inflammatory cells but also smooth muscle cells and fibroblasts generated ROS. There was a correlation between ROS and the expression of p22 phox or oxidized LDL. The generation of ROS was significantly higher in unstable angina pectoris compared with stable angina pectoris. Conclusions— ROS generated by p22 phox -based NADH/NADPH oxidase likely mediate the oxidative modification of LDL and might play a major role in pathogenesis of atherosclerotic coronary artery disease.

Several reports have been published of the acceptable patency and limb salvage rates following infra-popliteal interventions for the treatment of critical limb ischemia (CLI). However, the optimal angiographic endpoint of endovascular therapy (EVT) remains unclear. The aim of this study was to

Early phase arterial reaction after 2 second-generation drug-eluting stents (2nd DES) and bare-metal stent (BMS) implantation in patients with ST-segment elevated myocardial infarction (STEMI) remains unclear. MECHANISM pilot study is a multi-center prospective registry enrolling 24 STEMI patients

The assessment of right ventricular (RV) function plays an important role in the management of patients with pulmonary hypertension (PH). The current guideline's recommendation has been routinely to use tricuspid annular plane systolic excursion (TAPSE) as a simple method of estimating RV function.

Adverse plaque characteristics (APCs) by coronary CT angiography (CTA) are associated with myocardial ischemia and future acute coronary syndromes. We sought to determine whether APCs on CTA are associated with vulnerable plaque features by optical coherence tomography (OCT). Sixty-eight coronary

Background —The results of recent studies suggest that NO synthase may increase in the failing myocardium and that NO modulates the myocardial contractile response to β-adrenergic stimulation. However, there are few data regarding the physiological role of NO in patients with heart failure. The aim of the present study was to address the role of NO in left ventricular (LV) contractile response to β-adrenergic stimulation and corresponding oxygen expenditure in human heart failure. Methods and Results —We studied 15 patients with heart failure due to idiopathic dilated cardiomyopathy (mean ejection fraction 0.33). We examined LV contractility (E max , the slope of end-systolic pressure-volume relation), LV external work (EW), myocardial oxygen consumption (MV̇ o 2 ), and mechanical efficiency (measured as EW/MV̇ o 2 ) with the use of conductance and coronary sinus thermodilution catheters before and during dobutamine (DOB) infusion via a peripheral vein (4.8±0.3 μg · kg −1 · min −1 IV). Heart rate was kept constant with atrial pacing. We carried out a similar protocol during the intracoronary infusion of the NO synthase inhibitor N G -monomethyl- l -arginine (L-NMMA; 200 μmol). DOB increased E max , EW, and MV̇ o 2 (by 77±17%, 39±5%, and 21±5%, respectively), leading to an increase in mechanical efficiency (25.4±3.1% to 29.6±4.1%). L-NMMA alone did not significantly change these variables. Although the concurrent infusion of DOB with L-NMMA increased E max , EW, and MV̇ o 2 (by 140±21%, 64±9%, and 35±5%, respectively) more than DOB alone, mechanical efficiency did not increase further (24.3±3.3% to 29.5±4.5%) because EW and MV̇ o 2 increased in parallel. Conclusions —These data suggest that in patients with idiopathic dilated cardiomyopathy, endogenous NO spares MV̇ o 2 through attenuation of LV contractile response to β-adrenergic stimulation while maintaining LV energy-converting efficiency.

It has been shown recently that the force-frequency relationship is blunted in experimental heart failure models. Furthermore, tachycardia is thought to have adverse effects on the diseased heart for several reasons, one of which is an increase in myocardial oxygen consumption. Inversely, the oxygen-saving effects of bradycardia may be beneficial for the treatment of heart failure. The aim of this study was to elucidate how heart rate (HR) modulates cardiac mechanics and energetics in patients with left ventricular (LV) dysfunction. LV pressure-volume data and myocardial oxygen consumption (MVO2) was assessed using conductance and coronary sinus thermodilution catheters in 14 patients with moderate LV dysfunction (mean ejection fraction 34%) under 3 conditions: (a) basal, (b) HR increased by 20% using atrial pacing, and (c) HR decreased by 16% using a specific bradycardic agent, zatebradine (7.5 mg po). Atrial pacing decreased external work (EW) (from 0.39 to 0.31 J beat-1 m-2, p

Pathological studies have revealed atherosclerotic neointima (AN) after stent implantation. However, the risk factor of neoatherosclerosis and its impact on future clinical events remain unclear. From the Kobe university OCT database, 137 consecutive patients (253 stents) who underwent OCT

Recent optical coherence tomography (OCT) analyses have suggested strut–vessel wall (SV) distance of acute incomplete strut apposition (ISA) might predict persistent ISA after 1st–generation drug–eluting stents implantation. The impacts of SV distance and plaque character underneath acute ISA

Newer generation drug-eluting stents (DES) have applied better polymers including biodegradable one, however the long-term safety is still unclear. The aim of this study was to evaluate the long-term safety following sirolimus eluting (SES), everolimus eluting (EES), and biolimus eluting stent (BES

Background Drug coated balloons (DCBs) have shown efficacy for treatment of coronary artery disease. In PEPCAD II ISR trial, paclitaxel-coated balloon (PCB) reduced in-stent restenosis (ISR) compared with paclitaxel-eluting stent (PES). Here we evaluated the efficacy of PCB in porcine ISR model. Materials and methods 32 coronary arteries (LAD: n=12, LCX: n=11, RCA: n=9) of 12 Yorkshire pigs were assigned to two (2) groups randomly. PCB (SeQuent, length 20 mm, n=16) or non-coating balloon (NCB, length 20 mm n=16) were inflated for 60 s with B:A 1.2:1 followed by BMS (length 12 mm) implantation (S/A 1.5:1) within the target region. At 28 days, animals underwent restudy for the assessment of quantitative coronary angiography (QCA) and optical coherence tomography (OCT). Results There were no differences between groups among all of the parameters measured by QCA and OCT. QCA late luminal loss was 1.27±0.57 mm for PCB and 1.11±0.52 mm for NCB (p=NS). Similarly, the percent of in-stent stenosis was 34.5±15.0% for PCB and 36.2±13.6% for NCB (p=NS). OCT image analysis, showed that the mean thickness of neointimal hyperplasia (NIH) on stent strut was 585±219 μm for PCB compared to 661±183 μm for NCB (p=NS), and the percent of in-stent area stenosis was 43.2±14.9% for PCB, and 49.5±11.5% for NCB (p=NS). Conclusions In the current experimental setting, we didn9t observed inhibition of neointimal formation response to PCB therapy as determined by both QCA and OCT measurement.

Purpose: The purpose of our study was to evaluate the procedural success, 6-month patency, and clinical outcome of a new 4F sheath-compatible, selfexpanding nitinol stent after failed conventional angioplasty or atherectomy of infrapopliteal lesions in critical limb ischemia (CLI). Methods: Clinical records of 13 patients with CLI (Rutherford class 4–6), who underwent stent implantation following percutaneous transluminal angioplasty (PTA) and/or atherectomy were reviewed. Stent placement was carried out due flow-limiting dissections, or elastic recoil after PTA. Before and after the intervention and during the 6-month follow-up, clinical evaluation and color-flow and duplex Doppler ultrasonography were performed. Technical success, primary patency at 6 months, and clinical improvement as defined by Rutherford with clinical and hemodynamic measures and complications were evaluated. Results: A total of 19 arterial territories were intervened upon. 4F Sheathcompatible, self-expanding nitinol stent system (XPERT; Abbott Vascular) with a diameter of 3–5 mm and a length of 20–60 mm was used. A total of 29 stents were deployed. Stent implantation was successfully performed in all patients. After stent placement, the primary cumulative patency rate for the study group at 6 months was 90%. The mean resting ankle-brachial index at baseline was 0.40±0.1 and significantly increased to 0.90±0.13 (Pb.001) at 24 h after intervention and 0.84±0.15 at 6-month follow-up (P b.001). The sustained clinical improvement rate was 78% at the 6-month follow-up. The 6-month limb salvage rate regarding major amputation was 85%. One patient (7.7%) developed major access site bleeding requiring transfusion. Conclusions: Nitinol self-expanding stents in infrapopliteal arteries can be deployed safely with good short-term patency rate and clinical benefit in the treatment of CLI.

Purpose: The purpose of our study was to evaluate the procedural success, 6-month patency, and clinical outcome of a new 4F sheath-compatible, selfexpanding nitinol stent after failed conventional angioplasty or atherectomy of infrapopliteal lesions in critical limb ischemia (CLI). Methods: Clinical records of 13 patients with CLI (Rutherford class 4–6), who underwent stent implantation following percutaneous transluminal angioplasty (PTA) and/or atherectomy were reviewed. Stent placement was carried out due flow-limiting dissections, or elastic recoil after PTA. Before and after the intervention and during the 6-month follow-up, clinical evaluation and color-flow and duplex Doppler ultrasonography were performed. Technical success, primary patency at 6 months, and clinical improvement as defined by Rutherford with clinical and hemodynamic measures and complications were evaluated. Results: A total of 19 arterial territories were intervened upon. 4F Sheathcompatible, self-expanding nitinol stent system (XPERT; Abbott Vascular) with a diameter of 3–5 mm and a length of 20–60 mm was used. A total of 29 stents were deployed. Stent implantation was successfully performed in all patients. After stent placement, the primary cumulative patency rate for the study group at 6 months was 90%. The mean resting ankle-brachial index at baseline was 0.40±0.1 and significantly increased to 0.90±0.13 (Pb.001) at 24 h after intervention and 0.84±0.15 at 6-month follow-up (P b.001). The sustained clinical improvement rate was 78% at the 6-month follow-up. The 6-month limb salvage rate regarding major amputation was 85%. One patient (7.7%) developed major access site bleeding requiring transfusion. Conclusions: Nitinol self-expanding stents in infrapopliteal arteries can be deployed safely with good short-term patency rate and clinical benefit in the treatment of CLI.