Effect of proximal optimization technique on coronary bifurcation stent failure: Insights from the multicenter randomized PROPOT trial.

OBJECTIVE: We investigated the effect of proximal optimization technique (POT) on coronary bifurcation stent failure (BSF) in cross-over stenting by comparing with the kissing balloon technique (KBT) in a multicenter randomized PROPOT trial. BACKGROUND: POT is recommended due to increased certainty for optimal stent expansion and side branch (SB) wiring. METHODS: We randomized 120 patients treated with crossover stenting into the POT group, which was followed by SB dilation (SBD), and the KBT group. Finally, 52 and 57 patients were analyzed by optical coherence tomography before SBD and at the final procedure, respectively. Composite BSF was defined as a maximal malapposition distance of >400 µm, or malapposed and SB-jailed strut rates of >5.95% and >21.4%, respectively. RESULTS: Composite BSF before SBD in the POT and KBT groups was observed in 29% and 26% of patients, respectively. In the POT group, differences in stent volumetric index between the proximal and distal bifurcation (odds ratio [OR] 60.35, 95% confidential interval [CI] 0.13-0.93, p = 0.036) and between the proximal bifurcation and bifurcation core (OR: 3.68, 95% CI: 1.01-13.40, p = 0.048) were identified as independent risk factors. Composite BSF at final in 27% and 32%, and unplanned additional procedures in 38% and 25% were observed, respectively. Composite BSF before SBD was a risk factor for the former (OR: 6.33, 95% CI: 1.10-36.50, p = 0.039) and the latter (OR: 6.43, 95% CI: 1.25-33.10, p = 0.026) in the POT group. CONCLUSION: POT did not result in a favorable trend in BSF. Insufficient expansion of the bifurcation core after POT was associated with BSF.

Are there gender differences in the association between body mass index and left ventricular diastolic function? A clinical observational study in the Japanese general population.

BACKGROUND: Increased body mass index (BMI) is a major risk factor for heart failure with preserved ejection fraction (HFpEF), and HFpEF is more prevalent in elderly females than males. We hypothesized that there may be gender differences in the association between BMI and echocardiographic left ventricular (LV) diastolic parameters. METHODS: We enrolled 456 subjects (243 males) without overt cardiac diseases, all of whom underwent a health checkup. Early (E) and late (A) diastolic transmitral flow velocity, early diastolic mitral annular velocity (e'), and left atrial (LA) volume index were measured by echocardiography to assess LV diastolic function. To examine gender differences in the association between BMI and LV diastolic function, we analyzed the interaction effects of gender on the association between BMI and echocardiographic LV diastolic parameters. RESULTS: Although there were significant gender differences in the association between BMI and E/A and e' in the crude model (interaction effect 0.037 and 0.173, respectively; P = .006 and .022, respectively), these differences were not statistically significant after adjustment for factors related to LV diastolic function. On the other hand, there were significant associations between BMI and LV diastolic parameters in each gender, even after adjustment. CONCLUSIONS: Our findings suggest there is no gender difference in the association between BMI and echocardiographic LV diastolic parameters. However, the association between BMI and LV diastolic parameters was significant in both genders. Controlling body weight might be beneficial for both women and men to prevent progression of LV diastolic dysfunction and development of HFpEF.

Impact of Residual Stenosis on the Angiographic Edge Restenosis of a Second-Generation Drug-Eluting Stent.

Edge restenosis has gained attention as a main cause of restenosis after first-generation drug-eluting stent (DES) implantation. The aim of this study was to assess the incidence of edge restenosis and identify the predictors of edge restenosis after second-generation DES implantation. Data were obtained from several postmarketing surveillance (PMS) studies on a cobalt-chromium everolimus-eluting stent (CoCr-EES; Xience V/PROMUS, Xience Prime, Xience Prime SV, and Xience Expedition SV), a second-generation DES, in Japan. Angiographic analysis was conducted at the baseline and after eight months on the following subsegments: in-stent region, proximal edge, and distal edge. Restenosis was defined as ≥ 50% diameter stenosis (DS) at follow-up. We used multivariate logistic regression (with lesions as a random effect) to compare the instances of restenosis between the proximal and the distal edges. Univariate and multivariate analyses of the risk factors for restenosis were performed for each subsegment. We analyzed 1,966 lesions in 1,687 patients. The restenosis rates at the in-stent region, proximal edge, and distal edge were 4.4%, 3.0%, and 1.1%, respectively. The risk of restenosis at the distal edge was significantly lower than that at the proximal edge, when adjusted for 13 variables. The predictors of restenosis were postprocedural % diameter stenosis (%DS), postprocedural reference diameter, ≥ 45° bending, stent overlap at the proximal edge, and postprocedural %DS at the distal edge. Our analysis of eight-month angiographic outcomes from CoCr-EES PMS demonstrated that postprocedural %DS is a major predictor of edge restenosis. Edge restenosis is more likely attributable to postprocedural angiographic results than to the patient's background.

Impact of coronary bifurcation angle on stent malapposition in a randomized comparison between proximal optimization technique followed by side branch dilatation and kissing balloon inflation.

Background: The impact of coronary bifurcation angle (BA) on incomplete stent apposition (ISA) after crossover stenting followed by side branch (SB) intervention has not been established. Methods: A total of 100 crossover stentings randomly treated with proximal optimization technique followed by short balloon dilation in the SB (POT-SBD group, 48 patients) and final kissing balloon technique (KBT group, 52 patients) were analyzed in the PROPOT trial. Major ISA with maximum distance > 400 µm and its location was determined using optical coherence tomography before SB intervention and at the final procedure. The BA was defined as the angle between the distal main vessel and SB. Optimal POT was determined when the difference in stent volume index between the proximal and distal bifurcation was greater than the median value (0.86 mm3/mm) before SB intervention. Result: Major ISA was more frequently observed in the POT-SBD than in the KBT group (35% versus 17%, p < 0.05). In the POT-SBD group, worsening ISA after SBD was prominent at the distal bifurcation. The BA was an independent predictor of major ISA (odds ratio 1.04, 95% confidence interval 1.00-1.07, p < 0.05) with a cut-off value of 59.5° (p < 0.05). However, the cases treated with optimal POT in the short BA (<60°) indicated the lowest incidence of major ISA. In the KBT group, BA had no significant impact. Conclusion: A wide BA has a potential risk for the occurrence of major ISA after POT followed by SBD in coronary bifurcation stenting.

Multivariable prediction model to estimate the probability of restenosis at proximal edge after 2nd-generation drug-eluting-stent implantation: development and internal validation using a quantitative coronary angiography from the post-marketing surveillance studies of everolimus-eluting stent in Japan.

Edge restenosis has still been reported after second-generation drug-eluting stent (DES) implantation. It was more likely attributable to post-procedural angiographic results than to the patient's background. The aim of this study was to develop and internally validate a prediction model for restenosis in proximal edge after 2nd-generation DES stent implantation using angiographic data. Data were obtained from several post-marketing surveillance (PMS) studies of the cobalt-chromium everolimus-eluting stent (CoCr-EES) and platinum-chromium everolimus-eluting stent (PtCr-EES), second-generation DES, in Japan. Angiographic analysis was conducted at baseline and after 8 or 12 months. We focused on the proximal edge of angiographic analysis. The main outcome was restenosis defined as ≥ 50% diameter stenosis at follow-up. The predictive performance of the prediction model based on multivariable logistic regression was assessed in terms of discrimination and calibration, which were internally validated by the bootstrap method. We also performed decision curve analysis to assess threshold of predicted probability of restenosis at which additional intervention was considered. Among 2053 lesions in 1860 patients, restenosis rates in proximal edge was 2.8%. The final model was constructed with % post-procedural diameter stenosis (DS) and post-procedural reference diameter (RD) as strong predictors for edge restenosis. Discrimination and calibration were satisfactory with optimism-corrected C-statistics 0.75. Predicted probability between 0.03 and 0.24 was preferable threshold for restenosis treatments. Our prediction model can be used to obtain valid prediction for restenosis in proximal edge, assisting to know complete stent coverage of lesion.

Proximal optimisation technique versus final kissing balloon inflation in coronary bifurcation lesions: the randomised, multicentre PROPOT trial.

BACKGROUND: Clinical implications of the proximal optimisation technique (POT) for bifurcation lesions have not been investigated in a randomised controlled trial. AIMS: This study aimed to investigate whether POT is superior in terms of stent apposition compared with the conventional kissing balloon technique (KBT) in real-life bifurcation lesions using optical coherence tomography (OCT). METHODS: A total of 120 patients from 15 centres were randomised into two groups - POT followed by side branch dilation or KBT. Finally, 57 and 58 patients in the POT and KBT groups, respectively, were analysed. OCT was performed at baseline, immediately after wire recrossing to the side branch, and at the final procedure. RESULTS: The primary endpoint was the rate of malapposed struts assessed by the final OCT. The rate of malapposed struts did not differ between the POT and KBT groups (in-stent proximal site: 10.4% vs 7.7%, p=0.33; bifurcation core: 1.4% vs 1.1%, p=0.67; core's distal edge: 6.2% vs 5.3%, p=0.59). More additional treatments were required among the POT group (40.4% vs 6.9%, p<0.01). At one-year follow-up, only one patient in each group underwent target lesion revascularisation (2.0% vs 1.9%). CONCLUSIONS: POT followed by side branch dilation did not show any advantages over conventional KBT in terms of stent apposition; however, excellent midterm clinical outcomes were observed in both strategies.

Two-by-two cross-over study to evaluate agreement between versions of a quantitative coronary analysis system (QAngio XA).

The current version (ver. 7.3) of the popular quantitative coronary analysis system QAngio XA (Medis Medical Imaging System BV, Leiden, the Netherlands) is widely used without evaluating the agreement between the current and older versions in relation to a change of algorithms. The purpose of this study was to assess the equivalence of averages between QAngio XA versions 7.3 and 6.0. Based on the calculated sample size, angiographic images of 100 patients who underwent percutaneous coronary intervention of a single target lesion were randomly selected from two published studies (OUCH-TL: 154 lesions; OUCH-PRO: 160 lesions). The primary endpoint was the minimum lumen diameter (MLD), and the secondary endpoints were the reference diameter (RefD) and length of the stenotic lesion (LL). Two independent analysts measured the same frame using both previous and current versions of QAngio XA. Version-order for each lesion was randomly determined per coronary locations targeted. Data were analysed by using a mixed model that includes random lesion effects and fixed rater effects and reading-order effects. A Bland-Altman plot of parameters showed no large differences between the versions. Differences in parameters were estimated by the mixed model, and the 95% confidence interval of the MLD, RefD, and LL estimates was from -0.045 to -0.0001 mm, from -0.040 to 0.006 mm, and from -1.08 to 0.46 mm, respectively, compared with the predefined non-inferiority margin of ±0.2 mm. Measurements of MLD and RefD using QAngio XA showed no major systematic differences between versions.