Myeong Ho Yoon

Usefulness of coronary pressure measurement for functional evaluation of drug-eluting stent restenosis.

Despite the widespread adoption of drug-eluting stent (DES) implantation, the optimal treatment of DES failures remains challenging. The present study evaluated the relation between quantitative angiography and the fractional flow reserve (FFR) in restenotic lesions after DES implantation and the efficacy of FFR in determining whether to treat these lesions. To assess their functional significance, the coronary pressure-derived FFR was measured in 50 DES restenotic lesions (49 patients). Additional intervention was performed in lesions with a FFR <0.8. Major adverse cardiac events were assessed at 12 months after the reintervention procedure. The mean percent diameter stenosis (%DS) was 58 ± 13%. Of the 50 lesions, 20 (40%) were deferred without additional intervention. The FFR and %DS had a negative correlation (r = -0.61, p <0.001). However, when only the lesions with diffuse-type restenosis (15 lesions) were analyzed, the degree of correlation decreased (r = -0.56, p = 0.12). Although most lesions (89%) with a %DS of ≥70 had significant functional ischemia, among 41 lesions with a %DS <70, only 20 (49%) had demonstrated functional patency. The incidence of adverse events during the 12 months of follow-up after FFR-guided treatment was 18.0% (23.3% in the FFR <0.80 group and 10.0% in FFR ≥0.80 group). In conclusion, a discrepancy was found between functional ischemia measured by the FFR and the angiographic %DS, in particular, in moderate- or diffuse-type restenotic lesions after DES implantation. The outcome of FFR-guided deferral in patients with DES in-stent restenosis seems favorable.

Impact of Female Gender on Bleeding Complications After Transradial Coronary Intervention (from the Korean Transradial Coronary Intervention Registry)

Besides poor clinical outcomes, female gender has been known as a high-risk factor for bleeding complications. This study aimed to investigate the impact of gender on clinical outcomes and bleeding complications after transradial coronary intervention (TRI). The Korean TRI registry is a retrospective multicenter registry with 4,890 patients who underwent percutaneous coronary intervention in 2009 at 12 centers. To compare clinical outcomes and bleeding complications between the male and female groups, we performed a propensity score matching in patients who received TRI. A total of 1,194 patients (597 in each group) were studied. The primary outcome was 1-year major adverse cardiac events, including all-cause mortality, myocardial infarction, target vessel revascularization, and stroke. The secondary outcome was major bleeding (composite of bleeding requiring transfusion of ≥2 units of packed cells or bleeding that was fatal). The proportion of major adverse cardiac events was similar between the 2 groups (6.2% vs 4.7%, p = 0.308). The female group had a greater incidence of major bleeding (0.3% vs 3.2%, p <0.001). On multivariate analysis, female gender (odds ratio [OR] 7.748, 95% confidence interval [CI] 1.767 to 13.399), age ≥75 years (OR 5.824, 95% CI 2.085 to 16.274), and chronic kidney disease (OR 7.264, 95% CI 2.369 to 12.276) were independent predictors of major bleeding. In conclusion, the female gender had a tendency for more bleeding complications than male gender after TRI without difference in the clinical outcome.

Validation of three-dimensional echocardiography for quantification of aortic root geometry: comparison with multi-detector computed tomography.

Background Three-dimensional (3D) echocardiography has been reported to be valuable for evaluating the geometry of cardiac chambers. We validated the accuracy of 3D transthoracic echocardiography for quantifying aortic root geometry in comparison with cardiac multi-detector computed tomography (MDCT). Methods Twenty-three patients who underwent cardiac MDCT and showed normal left ventricular ejection fraction (> 55%), as assessed by 2-dimensional transthoracic echocardiography, were enrolled (12 male, mean 53 ± 9 years). We defined the aortic root volume as the volume from the aortic annulus to the sinotubular junction. The aortic root volume at end-diastole measured by both cardiac MDCT and 3D echocardiography was assessed. Results The cross-sectional area of the aortic root was asymmetric. At the annulus level, the cross-sectional area showed asymmetric triangle. From the aortic annulus to the most dilated point of the sinus of Valsalva, the asymmetric triangular shape was maintained. From the most dilated point of the sinus of Valsalva to the sinotubular junction, the cross-sectional shape of the aortic root changed to oval. The average aortic root volumes measured by 3D echocardiography (ARV-3DE) were 13.6 ± 4.8 mL at end-diastole and 14.1 ± 5.3 mL at end-systole, respectively. The average aortic root volume measured by MDCT at end-diastole (ARV-CT) was 14.1 ± 5.7 mL. At end-diastole, the ARV-3DE correlated well with the ARV-CT (R2 = 0.926, difference = 0.5 ± 1.7 mL), and the two methods were in excellent agreement (the percent difference was 0%). Conclusion Our results demonstrate both the feasibility and accuracy of 3D echocardiography for the clinical assessment of the geometry of the aortic root.

Impact of age on the functional significance of intermediate Epicardial artery disease

BACKGROUND The functional significance of an intermediate coronary lesion is crucial for determining the treatment strategy, but age-related changes in cardiovascular function could affect the functional significance of an epicardial stenosis. The aim of this study was therefore to investigate the impact of age on fractional flow reserve (FFR) measurements in patients with intermediate coronary artery disease (CAD). METHODSANDRESULTS Intracoronary pressure measurements and intravascular ultrasound (IVUS) were performed in 178 left anterior descending coronary arteries with intermediate stenosis. The morphological characteristics and FFR of 91 lesions in patients <65 years old were compared with those of 87 patients ≥65 years old. There was no difference in lesion location, diameter stenosis, minimum lumen area, plaque burden, or lesion length between the 2 age groups. Elderly patients had higher FFR (0.81±0.06 vs. 0.79±0.06, P=0.004) and lower ∆FFR, defined as the difference between resting Pd/Pa and FFR (0.13±0.05 vs. 0.15±0.05, P=0.014). Age, along with the location and degree of stenosis, was independently associated with FFR and ∆FFR (β=0.162, P=0.008; β=-0.131, P=0.043, respectively). CONCLUSIONS Elderly patients with intermediate CAD are more likely to have higher FFR and lower ∆FFR, despite a similar degree of epicardial stenosis, compared with younger patients. (Circ J 2016; 80: 1583-1589).

Study protocol for a randomised controlled trial: harmonising optimal strategy for treatment of coronary artery stenosis — coronary intervention with next-generation drug-eluting stent platforms and abbreviated dual antiplatelet therapy (HOST-IDEA) trial

Introduction We have recently seen the introduction of newer generation drug-eluting stents with ultrathin struts that use advanced polymer technologies. However, the efficacy and safety of these newest stents have not yet been fully explored. In addition, there are still controversies over the optimal duration of dual antiplatelet therapy (DAPT) after stent implantation, particularly for ultrathin stents with the newest polymer technologies. Methods and analysis The HOST-IDEA trial is a randomised, open-label, multicentre, non-inferiority trial and the first study to directly compare two of these ultrathin sirolimus-eluting stents: Orsiro stent with biodegradable polymer, and polymer-free Coroflex ISAR (CX-ISAR) stent. This study has a scheme of 2×2 factorial design according to the stent type and DAPT duration (3 vs 12 months). A total of 2152 patients will be randomised and stratified to demonstrate the non-inferiority of CX-ISAR to Orsiro, or of the abbreviated DAPT duration to the conventional 12 months (both in 1:1 ratio). For the comparison of stent type, the primary endpoint is target lesion failure (TLF), which is a composite of cardiac death, target vessel-related myocardial infarction and clinically driven target lesion revascularisation. For the comparison of DAPT duration, the net adverse clinical event is the coprimary endpoint, which is defined as a composite of TLF, definite/probable stent thrombosis and major bleeding. Ethic approval and dissemination All the institutions involved in this study are required to have ethical approval prior to patient enrolment. This multicentre study will recruit patients through competitive registration, but institutions that have not yet obtained ethical approvals have made it impossible to enrol patients in a centralised web database. The final results will be presented at relevant international conferences and will be materialised in the form of papers. Trial registration number NCT02601157; Pre-results.

Clinical and Angiographic Outcomes of the First Korean-made Sirolimus-Eluting Coronary Stent with Abluminal Bioresorbable Polymer

Background and Objectives This trial evaluated the safety and efficacy of the Genoss drug-eluting coronary stent. Methods This study was a prospective, multicenter, randomized trial with a 1:1 ratio of Genoss drug-eluting stent (DES)™ and Promus Element™. Inclusion criteria were the presence of stable angina, unstable angina, or silent ischemia. Angiographic inclusion criteria were de novo coronary stenotic lesion with diameter stenosis >50%, reference vessel diameter of 2.5–4.0 mm, and lesion length ≤40 mm. The primary endpoint was in-stent late lumen loss at 9-month quantitative coronary angiography follow-up. Secondary endpoints were in-segment late lumen loss, binary restenosis rate, death, myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), and stent thrombosis during 9 months of follow-up. Results We enrolled 38 patients for the Genoss DES™ group and 39 patients for the Promus Element™ group. In-stent late lumen loss at 9 months was not significantly different between the 2 groups (0.11±0.25 vs. 0.16±0.43 mm, p=0.567). There was no MI or stent thrombosis in either group. The rates of death (2.6% vs. 0%, p=0.494), TLR (2.6% vs. 2.6%, p=1.000), and TVR (7.9% vs. 2.6%, p=0.358) at 9 months were not significantly different. Conclusion This first-in-patient study of the Genoss DES™ stent showed excellent angiographic outcomes for in-stent late lumen loss and major adverse cardiac events over a 9-month follow-up.

Clinical Outcomes in Patients with Deferred Coronary Lesions according to Disease Severity Assessed by Fractional Flow Reserve

Data on the clinical outcomes in deferred coronary lesions according to functional severity have been limited. This study evaluated the clinical outcomes of deferred lesions according to fractional flow reserve (FFR) grade using Korean FFR registry data. Among 1,294 patients and 1,628 lesions in Korean FFR registry, 665 patients with 781 deferred lesions were included in this study. All participants were consecutively categorized into 4 groups according to FFR; group 1: ≥ 0.96 (n = 56), group 2: 0.86–0.95 (n = 330), group 3: 0.81–0.85 (n = 170), and group 4: ≤ 0.80 (n = 99). Primary endpoint was major adverse cardiac events (MACE), a composite of all-cause death, myocardial infarction, and target vessel revascularization. The median follow-up period was 2.1 years. During follow-up, the incidence of MACE in groups 1–4 was 1.8%, 7.6%, 8.8%, and 13.1%, respectively. Compared to group 1, the cumulative rate by Kaplan-Meier analysis of MACE was not different for groups 2 and 3. However, group 4 had higher cumulative rate of MACE compared to group 1 (log-rank P = 0.013). In the multivariate Cox hazard models, only FFR (hazard ratio [HR], 0.95; P = 0.005) was independently associated with MACE among all participants. In contrast, previous history of percutaneous coronary intervention (HR, 2.37; P = 0.023) and diagnosis of acute coronary syndrome (ACS) (HR, 2.35; P = 0.015), but not FFR, were independent predictors for MACE in subjects with non-ischemic (FFR ≥ 0.81) deferred coronary lesions. Compared to subjects with ischemic deferred lesions, clinical outcomes in subjects with non-ischemic deferred lesions according to functional severity are favorable. However, longer-term follow-up may be necessary.

SU-E-T-163: Evaluation of Dose Distributions Recalculated with Per-Field Measurement Data Under the Condition of Respiratory Motion During IMRT for Liver Cancer

PURPOSE The dose distributions within the real volumes of tumor targets and critical organs during internal target volume-based intensity-modulated radiation therapy (ITV-IMRT) for liver cancer were recalculated by applying the effects of actual respiratory organ motion, and the dosimetric features were analyzed through comparison with gating IMRT (Gate-IMRT) plan results. METHODS The 4DCT data for 10 patients who had been treated with Gate-IMRT for liver cancer were selected to create ITV-IMRT plans. The ITV was created using MIM software, and a moving phantom was used to simulate respiratory motion. The period and range of respiratory motion were recorded in all patients from 4DCT-generated movie data, and the same period and range were applied when operating the dynamic phantom to realize coincident respiratory conditions in each patient. The doses were recalculated with a 3 dose-volume histogram (3DVH) program based on the per-field data measured with a MapCHECK2 2-dimensional diode detector array and compared with the DVHs calculated for the Gate-IMRT plan. RESULTS Although a sufficient prescription dose covered the PTV during ITV-IMRT delivery, the dose homogeneity in the PTV was inferior to that with the Gate-IMRT plan. We confirmed that there were higher doses to the organs-at-risk (OARs) with ITV-IMRT, as expected when using an enlarged field, but the increased dose to the spinal cord was not significant and the increased doses to the liver and kidney could be considered as minor when the reinforced constraints were applied during IMRT plan optimization. CONCLUSION Because Gate-IMRT cannot always be considered an ideal method with which to correct the respiratory motional effect, given the dosimetric variations in the gating system application and the increased treatment time, a prior analysis for optimal IMRT method selection should be performed while considering the patients respiratory condition and IMRT plan results.

TCT-629 Long-term clinical outcomes after real world use of fractional flow reserve

Recent randomized trials showed that FFR-guided revascularization is safe and effective. However, long-term clinical outcomes of real world use of FFR, including the decisions against FFR, have not been fully evaluated. 1294 patients who underwent FFR measurement for de novo coronary lesions were

SU‐GG‐T‐465: Secondary Doses for the Treatment of Lung and Liver Cancers: IMRT vs. Proton Therapy

Purpose: To quantify and compare the secondary doses induced by advanced radiotherapy modalities, intensity‐modulated radiotherapy(IMRT) and proton beam therapy (PBT), for the treatment of lung and livercancers.Method and Materials:IMRT with 6 MV photon and proton beam therapy were planned for 3 lung and 3 livercancer patients. The treatment beams were delivered to phantom and corresponding secondary doses during irradiation were measured at various points from 20 cm to 50 cm apart from the beam isocenter using ion chamber and CR‐39 detectors for IMRT and PBT, respectively. Results: The average secondary doses of proton therapy for lung and livercancer patients, measured 20 to 50 cm from the isocenter, ranged from 1.73 mSv/Gy to 0.86 mSv/Gy. The average secondary doses of IMRT for lung patients, however, ranged between 5.8 mSv/Gy and 1.0 mSv/Gy, approximately three times higher than for proton therapy. The average internal neutrondoses of proton therapy for lung and livercancer patients, measured 20 to 50 cm from the isocenter, ranged from 0.21 mSv/Gy to 0.08 mSv/Gy. The result shows that internal neutrondose produced by proton interaction in the body is generally much less than external neutrondose produced by proton interactions in the scattering elements of the passively modulated beam line. Conclusion: By a comparison between passive proton beam therapy and IMRT for diseases of lung and livercancer, it was shown that the secondary doses using scattering mode in proton beam therapy is either significantly lower than the cases in IMRT treatment or, at least, does not exceed the secondary doses induced by conventional IMRT treatment.