Toshinari Onishi

Serial Angioscopic Evidence of Incomplete Neointimal Coverage After Sirolimus-Eluting Stent Implantation Comparison With Bare-Metal Stents

Background— The time course of neointimal formation after stent implantation has not been studied extensively by angioscopy in the drug-eluting stent era. Methods and Results— Serial angioscopic findings at first follow-up (3.6±1.1 months), second follow-up (10.5±1.6 months), and third follow-up (21.2±2.2 months) after stent implantation were compared between sirolimus-eluting stents (SES, n=17) and bare-metal stents (BMS, n=11). Neointimal coverage, thrombus, and presence of yellow plaques underneath the stents were assessed. Neointimal coverage was graded as follows: grade 0, stent struts were fully visible; grade 1, struts bulged into the lumen, although they were covered; grade 2, struts were embedded by the neointima but were seen translucently; or grade 3, struts were fully embedded and invisible. Neointimal coverage was remarkably different between SES and BMS at each follow-up point. Neointimal coverage grade was 1.1±0.5 in SES versus 2.9±0.3 in BMS at the first follow-up (P<0.0001), 1.1±0.5 in SES versus 3.0±0.0 in BMS (P<0.0001) at the second follow-up, and 1.3±0.5 in SES versus 3.0±0.0 in BMS at the third follow-up (P=0.0009). No significant serial changes in coverage grade were noted in the BMS group, whereas coverage grade slightly but significantly increased at the third follow-up in the SES group (P<0.05). Thrombi were detected in 4 SES: a red thrombus was seen from the first to the third follow-up in 2; another was detected only at the third follow-up; and the fourth was seen at the first follow-up but disappeared at the second follow-up, associated with a new white thrombus despite dual antiplatelet therapy. Yellow plaques had disappeared by the time of the second follow-up in BMS. In contrast, yellow plaques were exposed in 71% of SES at the first follow-up and remained exposed until the third follow-up. Neointimal coverage grades correlated with thrombi (P=0.002) and with yellow plaques (P<0.0001). Conclusions— Serial angioscopic findings up to 2 years after SES implantation were markedly different from those after BMS. Neointimal coverage was completed by 3 to 6 months in BMS. In contrast, SES demonstrated the presence of thrombi and yellow plaques even as much as 2 years after implantation.

New Self-Expanding Transcatheter Aortic Valve Device for Transfemoral Implantation – Early Results of the First-in-Asia Implantation of the ACURATE Neo/TF TM System –

BACKGROUND Feasibility and early results of transfemoral aortic valve implantation using the ACURATE neo/TF(TM)self-expanding stent are reported. METHODS AND RESULTS The study group of 15 patients (mean age 83.3±6.0) was enrolled with a mean EuroSCORE and STS score of 21.9±11.6% and 7.5±3.1%, respectively. Clinical and echocardiographic evaluations were performed at baseline, discharge, 30 days and 6 months. The primary endpoint was all-cause mortality at 30 days. Transcatheter aortic valve implantation (TAVI) using the ACURATE neo/TF device was successful in 14 patients; 1 patient underwent valve-in-valve implantation because the prosthetic valve embolized during withdrawal of the delivery system. Conversion to surgery, coronary obstruction, peri-operative stroke, and pacemaker implantation did not occur at 30 days. Mean transvalvular gradients at discharge significantly decreased from 44.2±10.5 mmHg (preprocedural) to 7.7±3.1 mmHg (P<0.0001) and effective orifice area significantly increased from 0.77±0.12 to 1.69±0.25 cm(2)(P<0.0001). None or trace paravalvular leak was revealed in 50.0%, and no patient exhibited moderate or higher paravalvular leak. The overall mortality at 30 days and 6 months was 0% and 6.7%, respectively. CONCLUSIONS A new self-expanding TF TAVI device, ACURATE neo/TF, is safe and effective in the treatment of severe aortic stenosis in elderly patients at high risk for surgery.

Clinical Outcomes and Bioprosthetic Valve Function After Transcatheter Aortic Valve Implantation Under Dual Antiplatelet Therapy vs. Aspirin Alone

BACKGROUND Dual antiplatelet therapy (DAPT) is commonly used after transcatheter aortic valve implantation (TAVI); however, the supporting evidence is limited. To determine if aspirin alone is a better alternative to DAPT, we compared the outcomes of patients treated with DAPT or aspirin alone after TAVI.Methods and Results:We analyzed a total of 144 consecutive patients (92 females, mean age 83±6 years) who underwent implantation of a balloon-expandable transcatheter valve (SAPIEN or SAPIEN XT, Edwards Lifesciences). Patients were divided into DAPT (n=66) or aspirin-alone treatment groups (n=78). At 1 year after TAVI, the composite endpoint, which consisted of all-cause death, myocardial infarction, stroke, and major or life-threatening bleeding complications, occurred significantly less frequently (Kaplan-Meier analysis) in the aspirin-alone group (15.4%) than in the DAPT group (30.3%; P=0.031). Valve function assessed by echocardiography was similar between the 2 treatment groups with respect to effective orifice area (1.78±0.43 cm2in DAPT vs. 1.91±0.46 cm2in aspirin-alone group; P=0.13) and transvalvular pressure gradient (11.1±3.5 mmHg in DAPT vs. 10.3±4.1 mmHg in aspirin-alone group; P=0.31). CONCLUSIONS Treatment with aspirin alone after TAVI had greater safety benefits and was associated with similar valve function as DAPT. These results suggest that treatment with aspirin alone is an acceptable regimen for TAVI patients.

Early Outcomes in Japanese Dialysis Patients Treated With Transcatheter Aortic Valve Implantation

BACKGROUND Although transcatheter aortic valve implantation (TAVI) is a new alternative treatment with acceptable midterm results for high surgical risk patients, at present performing the procedure in dialysis patients is not reimbursed in Japan. METHODSANDRESULTS The study group of 17 dialysis patients (mean age, 76.7±5.0 years) underwent TAVI with the SAPIEN/SAPIEN XT. EuroSCORE and STS score were 25.0±19.0% and 15.4±12.3%, respectively. Transiliofemoral and transapical approaches were performed in 7 (41.2%) and 10 patients (58.8%), respectively. ICU and hospital stays after TAVI were 1.8±1.6 and 12.9±12.7 days, respectively. Mean transvalvular gradients at discharge significantly decreased from 45.9±13.3 mmHg to 10.7±4.3 mmHg (P<0.0001) and effective orifice area significantly increased from 0.78±0.17 to 1.69±0.37 cm(2)(P<0.0001). Device success was 87.5%. One patient required a valve-in-valve procedure on 187-postoperative-day for an acute increase in paravalvular leakage caused by initial lower implantation of the device. The overall mortality at 1 year was 0% and clinical efficacies at 30 days, 6 months, and 1 year were 93.8%, 83.3%, and 69.2%, respectively. CONCLUSIONS Satisfactory early results were achieved with TAVI in Japanese dialysis patients with a high surgical risk, indicating it is a safe and effective alternative for the treatment of aortic valve stenosis in such patients.

Clinical Significance of Pulmonary Arterial Capacitance Calculated by Echocardiography in Patients With Advanced Heart Failure

BACKGROUND Advanced left heart failure (HF) often accompanies post-capillary pulmonary hypertension related to RV afterload. Although pulmonary arterial capacitance (PAC), a measure of pulmonary artery compliance, reflects right ventricular (RV) afterload, the clinical utility of PAC obtained by echocardiography (echo-PAC) is not well established in advanced HF.Methods and Results:We performed right heart catheterization in advanced HF patients (n=30), calculating echo-PAC as stroke volume/(tricuspid regurgitation pressure gradient-pulmonary regurgitation pressure gradient). The difference between the echo-PAC and catheter-measured PAC values was insignificant (0.21±0.17 mL/mmHg, P=0.23). Echo-PAC values predicted both pulmonary arterial wedge pressure (PAWP) ≥18 mmHg and pulmonary vascular resistance ≥3 Wood units (P=0.02, area under the curve: 0.88, cutoff value: 1.94 mL/mmHg). Next, we conducted an outcome study with advanced HF patients (n=72). Patients with echo-PAC <1.94 mL/mmHg had more advanced New York Heart Association functional class, higher B-type natriuretic peptide plasma levels, larger RV and lower RV fractional area change than those with echo-PAC ≥1.94 mL/mmHg. They also had a significantly higher rate of ventricular assist device implantation or death, even after adjustment for indices related to HF severity or RV function during a 1-year follow-up period (P<0.01). CONCLUSIONS Decreased PAC as measured by echocardiography, indicating elevated PAWP and RV dysfunction, predicted poorer outcomes in patients with advanced HF.

Ratio of pulmonary artery diameter to ascending aortic diameter and severity of heart failure

BACKGROUND Treatment decisions in dilated cardiomyopathy (DCM) patients with severe heart failure (HF) and short clinical history are challenging because of the difficulty of determining HF stage or prognosis in the acute HF phase. We hypothesized that persistent decreased systemic or increased pulmonary arterial pressure, including in the sub-clinical phase, might affect the main pulmonary artery diameter (PAD), ascending aortic diameter (AoD), and their ratio (PAD/AoD). This study assessed AoD, PAD, and PAD/AoD by non-contrast computed tomography scans in DCM patients in the acute phase of HF and examined the association of these parameters with their clinical course. METHODS Of 261 screened individuals, we studied 110 consecutive hospitalized patients with DCM suspected of being in advanced stage of HF and 45 age-matched controls, assessing clinical data and later events (cardiac death or left ventricular assist device implantation). RESULTS Compared with controls, DCM patients had smaller AoD (26.6 ± 4.4 vs 30.6 ± 2.7 mm) and larger PAD (27.7 ± 3.5 vs 25.4 ± 2.8 mm) and PAD/AoD (1.05 ± 0.14 vs 0.83 ± 0.08; all p < 0.01). DCM patients with high PAD/AoD (median, > 1.05) had more frequent past HF hospitalizations, lower blood pressure, stroke volume, and ejection fraction, higher brain natriuretic peptide levels, smaller AoD, and similar PAD compared with patients with a low PAD/AoD. A higher PAD/AoD was associated with poorer outcomes even after adjusting for age, blood pressure, ejection fraction, or number of hospitalizations. CONCLUSION Assessment of AoD and PAD may have important clinical implications in determining whether DCM patients are in an advanced stage of HF with a poorer prognosis.

Reduced variability of visual left ventricular ejection fraction assessment with reference images: The Japanese Association of Young Echocardiography Fellows multicenter study

BACKGROUND Visual estimation of left ventricular ejection fraction (LVEF) is widely applied to confirm quantitative EF. However, visual assessment is subjective, and variability may be influenced by observer experience. We hypothesized that a learning session might reduce the misclassification rate. METHODS Protocol 1: Visual LVEFs for 30 cases were measured by 79 readers from 13 cardiovascular tertiary care centers. Readers were divided into 3 groups by their experience: limited (1-5 years, n=28), intermediate (6-11 years, n=26), and highly experienced (12-years, n=25). Protocol 2: All readers were randomized to assess the effect of a learning session with reference images only or feedback plus reference images. After the session, 20 new cases were shown to all readers following the same methodology. To assess the concordance and accuracy pre- and post-intervention, each visual LVEF measurement was compared to overall average values as a reference. RESULTS Experience affected the concordance in visual EF values among the readers. Groups with intermediate and high experience showed significantly better mean difference (MD), standard deviation (SD), and coefficient of variation (CV) than those with limited experience at baseline. The learning session with reference image reduced the MD, SD, and CV in readers with limited experience. The learning session with reference images plus feedback also reduced proportional bias. Importantly, the misclassification rate for mid-range EF cases was reduced regardless of experience. CONCLUSION This large multicenter study suggested that a simple learning session with reference images can successfully reduce the misclassification rate for LVEF assessment.