Shingo Mizuno

Co-Existence of Carotid Artery Disease, Renal Artery Stenosis, and Lower Extremity Peripheral Arterial Disease in Patients With Coronary Artery Disease

In atherosclerosis, carotid artery stenosis (CAS), renal artery stenosis (RAS), lower extremity peripheral arterial disease (PAD), and coronary artery disease (CAD) are common pathologic lesions; their interrelationship is, however, unclear. We studied concomitant multiple atherosclerotic lesions in patients with CAD to understand their prevalence and relations. A cross-sectional analysis was performed on data from consecutive patients who underwent nonemergent coronary angiography. Simultaneous carotid and renal artery Doppler studies and ankle-brachial systolic pressure measurements were reviewed to diagnose concomitant lesions and their severity. The study included 1,734 patients (aged 71 ± 9 years; 70% men), with prevalences of CAS, RAS, lower extremity PAD, and CAD of 6%, 7%, 13%, and 72%, respectively. In patients with CAD (n = 1,253), the prevalences of CAS, RAS, and lower extremity PAD were 7%, 9%, and 16%, respectively; 24% CAD patients had ≥1 additional atherosclerotic lesion. Significant interactions among the prevalences of these lesions were found. In addition, the extent of CAD and the prevalences of CAS, RAS, and lower extremity PAD were significantly correlated. Multivariate analysis supported these relationships. In conclusion, the prevalences of CAS, RAS, lower extremity PAD, and CAD were strongly interrelated in the study population; CAD severity was related to that of other atherosclerotic lesions. Additional systematic screening of other concomitant atherosclerotic lesions is recommended, especially in CAD patients having multivessel disease, left main disease, and/or already diagnosed with other concomitant atherosclerotic lesions.

Effect of the local hemodynamic environment on the de novo development and progression of eccentric coronary atherosclerosis in humans: Insights from PREDICTION

BACKGROUND Eccentric distribution of atheroma has been associated with plaques likely to rupture and cause an acute coronary syndrome, but the factors responsible for the development of eccentricity remain unknown. Endothelial shear stress (ESS) drives plaque formation. We aimed to investigate the role of the local ESS characteristics in the de novo development and progressive worsening of plaque eccentricity in humans. METHODS Vascular profiling (3-vessel 3D coronary reconstruction by angiography/intravascular ultrasound, and blood flow simulation for ESS computation) was performed in 374 patients at baseline & 6-10 months follow-up. At baseline, we identified (i) disease-free segments (n=2157), and (ii) diseased regions of luminal obstructions (n=408). RESULTS In disease-free regions, baseline low ESS magnitude (p<0.001), marked ESS circumferential heterogeneity (p=0.001), and their interaction (p=0.026) were associated with an increased probability of de novo eccentric plaque formation at follow-up. In diseased regions, baseline low ESS (odds ratio [OR]: 2.33, p=0.003) and large plaque burden (OR: 2.46, p=0.002) were independent predictors of substantially increasing plaque eccentricity index with worsening lumen encroachment. This combined outcome was more frequent in obstructions with both features vs. all others (33 vs. 12%; p<0.001). The incidence of percutaneous coronary intervention in worsening obstructions with increasing plaque eccentricity was higher (13.3 vs. 4.3%, p=0.011). CONCLUSIONS The local hemodynamic environment has a critical effect on the development of eccentric coronary plaques at both an early and advanced stage of atherosclerosis. Local ESS assessment could help in predicting sites prone to plaque disruption and acute coronary syndromes in humans.

Percutaneous coronary intervention using a virtual 3-Fr guiding catheter†

Background: We have recently reported a novel percutaneous coronary intervention (PCI) system using a hydrophilic‐coated sheathless guiding catheter (Virtual 3‐Fr, Medikit, Tokyo, Japan), which provides us with less invasive angioplasty and a puncture site injury equivalent to a conventional 3‐Fr introducer sheath. Here, we report the initial results of PCI using this novel system. Methods: A total of 36 coronary artery lesions of 27 patients were treated by using a virtual 3‐Fr PCI system. Procedural outcomes of virtual 3‐Fr PCI were retrospectively evaluated. Results: The mean age was 73.0 ± 8.7 years (range, 46–84 years), and 15 were men (56%). Access sites included the radial artery in 18 patients (67%), the brachial artery in eight patients (30%), and the femoral artery in 1 patients (4%). Among 36 lesions, seven were chronic total occlusions, and a virtual 3‐Fr PCI was successful in 33 lesions (92%). Among the successfully treated 33 lesions, coronary stents were deployed in 32 (97%), and intravascular ultrasound examination was performed in 19 (58%). Hemostasis was achieved immediately after PCIs in all cases. No access‐site related complications including radial artery occlusion were observed. Conclusions: The performance of a virtual 3‐Fr PCI system appears to be comparable to one using a regular 5‐Fr guiding catheter while the puncture‐site damage remains equivalent to that of a 3‐Fr introducer sheath. Virtual 3‐Fr PCI may have a potential to serve as a minimally invasive strategy for the treatment of coronary artery diseases.

In Vitro and Human Studies of a 4F Double-Coaxial Technique (“Mother-Child” Configuration) to Facilitate Stent Implantation in Resistant Coronary Vessels

Background— We recently developed a 4F child catheter that can be inserted into 6F or larger conventional guiding catheters. The use of 4F mother-child technique may improve the delivery of coronary stents to complex lesions. Accordingly, we sought to determine the potential of using a 4F mother-child technique to treat complex coronary lesions. Methods and Results— The support power and the trackability of the mother-child technique of 4-in-6 were evaluated using a coronary artery tree model. In addition, the results of 51 lesions treated by using a 4F child catheter were retrospectively analyzed. The in vitro experiment demonstrated that backup support of the 4-in-6 system was increased when the child catheter was advanced into the coronary tree ≥5 cm (P⩽0.01); further, the 4F child catheter was associated with superior trackability as compared with a 5F child catheter (15.0 cm [15.0 to 15.0] versus 13.0 cm [12.8 to 13.0], P<0.005). A total of 51 lesions, in which conventional techniques had been unsuccessful, were treated using the 4F mother-child technique. Lesion success was achieved in 48 (94%) lesions. Stent deployment was attempted in 44 (86%) and was successful in 40 of 44 (91%). There were 2 instances of stent dislodgment. Conclusions— With the superior trackability of the 4F child catheter and with increased backup support of the mother-child system, the 4F mother-child system provided >90% success rate for lesions in which conventional techniques had failed. The 4F mother-child system may become a viable alternative to conventional techniques in treating complex coronary lesions.

Efficacy and safety of pioglitazone in patients with ST elevation myocardial infarction treated with primary stent implantation

Background: Recent studies have shown that thiazolidinediones reduce neointimal hyperplasia after bare metal stent (BMS) implantation, but this drug group sometimes cause fluid retention that may lead to heart failure. Objectives: To examine the safety and efficacy of pioglitazone in patients with ST elevation myocardial infarction (STEMI) treated with primary BMS implantation. Methods: Diabetic or non-diabetic patients with STEMI (<12 h from onset) successfully treated with primary BMS implantation were randomised to either the pioglitazone (15 mg, up to 30 mg) or control groups. Patients in cardiogenic shock were excluded. Primary efficacy end point was percentage neointimal volume within the stented segment at 6 months using three-dimensional intravascular ultrasound. Safety end point was a composite of all-cause mortality, reinfarction, or heart failure requiring hospitalisation. Results: Between October 2005 and July 2007, 96 patients were randomised into the pioglitazone (n = 48) or control group (n = 48). At follow-up, mean (SD) percentage neointimal volume and neointimal volume index were significantly reduced in the pioglitazone group (22 (13)% vs 28 (13)%, p = 0.04; 1.5 (0.9) vs 2.0 (0.8) mm3/mm, p = 0.02, respectively). During 6 months, two control patients died, four patients (one in the pioglitazone group, three controls) had stent thrombosis resulting in reinfarction and three patients (two in the pioglitazone group, one control) had heart failure, resulting in a similar incidence of safety end point (3 vs 6). Conclusions: Treatment of pioglitazone reduced neointimal hyperplasia in patients with STEMI treated with primary stent implantation without placing the patient at increased risk of complications. Additional larger trials will be necessary to establish the clinical benefit of pioglitazone.

Comparison of Short- and Long-Term Outcomes of Percutaneous Coronary Intervention for Chronic Total Occlusions Between Patients Aged ≥75 Years and Those Aged <75 Years

Few reports are available on the safety and efficacy of percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) in older patients. In the present study, 284 patients who underwent PCI for CTOs were retrospectively evaluated by comparing the characteristics of 67 patients aged ≥75 years (the older group) and 217 patients aged <75 years (the younger group). Technical success was achieved in 77% of the patients in the older group and 79% of those in the younger group (p = 0.66). No significant differences were observed between the 2 groups in terms of the incidence of procedural complications. In the older group, a comparison between the patients with successful and failed PCI revealed significantly superior 3-year cardiac survival (97.6% vs 76.9%, p = 0.005). The 3-year cardiac survival of those with successful PCI was similar to that observed in the younger group. On multivariate analysis, successful PCI was found to be associated with a lower incidence of cardiac death in the older group (hazard ratio 0.09, 95% confidence interval 0.01 to 0.91, p = 0.042). In conclusion, this single-center, observational study suggests that PCI for CTOs can be performed with a high rate of procedural success and acceptably low mortality and morbidity in older patients, resulting in improved cardiac survival. Thus, PCI for CTO lesions should be included among the treatment strategies for older patients.

Prehospital Transfer Pathway and Mortality in Patients Undergoing Primary Percutaneous Coronary Intervention

BACKGROUND It is recommended that not only door-to-balloon time but also prehospital delay for primary percutaneous coronary intervention (PCI) should be improved. We investigated the effect of prehospital transfer pathway on onset-to-balloon time and prognosis in patients with ST-segment elevation myocardial infarction (STEMI) in Japan. METHODSANDRESULTS We analyzed data from 540 consecutive patients with primary PCI for STEMI. Patient clinical data and mortality were compared between patients who visited the family physician or non-PCI-capable hospitals and were then transferred to PCI-capable centers (indirect transfer patients), and those who directly visited PCI-capable centers (direct transfer patients). Onset-to-balloon time was longer in indirect transfer patients than in direct transfer patients (mean, 270 min; range, 180-480 min vs. 180 min, 120-240 min; P<0.001). In addition, patient prognosis was evaluated on Cox proportional regression analysis. Cardiac death and all-cause death were significantly higher in indirect transfer patients (odds ratios [OR], 2.17; 95% confidence intervals [95% CI]: 1.17-4.01, P=0.01; OR, 1.71; 95% CI: 1.09-2.68, P=0.02). These results were confirmed using propensity score matching for adjusted analyses. CONCLUSIONS Patients with indirect transfer to regional emergency departments of PCI centers had longer onset-to-balloon time and worse prognosis than those with direct transfer.

AVJ-514 Trial ― Baseline Characteristics and 30-Day Outcomes Following MitraClip® Treatment in a Japanese Cohort ―

BACKGROUND The MitraClip®system is a transcatheter-based therapeutic option for patients with chronic mitral regurgitation (MR) who are at high risk for surgery. A prospective, multicenter, single-arm study was initiated to confirm the transferability of this system to Japan.Methods and Results:Patients with symptomatic chronic moderate-to-severe (3+) or severe (4+) functional or degenerative MR with a Society of Thoracic Surgery (STS) score ≥8%, or the presence of 1 predefined risk factor were enrolled. Patients with left ventricular (LV) ejection fraction (EF) <30% were excluded. MR severity and LV function were assessed by an independent echocardiography core lab. Primary outcome included major adverse events (MAE) at 30 days and acute procedural success (APS). A total of 30 patients (age: 80±7 years; STS score: 10.3%±6.6%) were treated with the MitraClip®. At baseline, all patients had MR 3+/4+ with 53%/47% patients with degenerative/functional etiology with mean LVEF of 50.2±12.8%, and 37% of patients were NYHA class III/IV. APS was achieved in 86.7% with no occurrence of MAE. At 30 days, 86.7% of patients had MR ≤2+ and 96.7% were NYHA class I/II. CONCLUSIONS The MitraClip®procedure resulted in clinically meaningful improvements in MR severity, function and quality of life measures, and low MAE rates. These early results suggest the transferability of this therapy to appropriately selected Japanese patients. (Trial Registration: clinicaltrials.gov Identifier NCT02520310.).

Arterial Remodeling and Endothelial Shear Stress Exhibit Significant Longitudinal Heterogeneity Along the Length of Coronary Plaques

Atherosclerosis is determined by both systemic risk factors and local vascular mechanisms. The arterial remodeling in response to plaque development plays a key role in atherosclerosis. Compensatory expansive remodeling is an adaptive mechanism that maintains lumen patency as a plaque develops. In

Comparison of long‐term patency after endovascular therapy for superficial femoral artery occlusive disease between patients with and without hemodialysis

To compare long‐term patency after endovascular therapy (EVT) for superficial femoral artery (SFA) occlusive disease between patients with hemodialysis (HD; HD+) and those without HD (HD−).