Post-stent Fractional Flow Reserve Research Articles

Long-term association of post stent fractional flow reserve with clinical events

Abstract Background Low fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is associated with procedural factors in the stented segment and residual disease in the non-stented segment. Even the prognostic value of post-PCI FFR has been reported, its long-term clinical relevance has not been thoroughly investigated. Purpose We sought to investigate the long-term prognostic value of post-PCI FFR and its relative significance on future events in stented and non-stented segments. Methods The International Post-PCI FFR extended registry (NCT04684043) followed the 2,200 patients who underwent PCI and measured post-PCI FFR between June 2011 and May 2018. The primary outcome was target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction (TVMI), and target vessel revascularization (TVR) at 5 years. The secondary outcomes were a composite of cardiac death or TVMI at 5 years. Results The median value of post-PCI FFR of target vessels was 0.89 (IQR 0.84-0.93). The optimal cut-off value of post-PCI FFR for predicting TVF was 0.81, and that for predicting cardiac death or TVMI was 0.76, respectively. The cumulative incidence of TVF was significantly higher in the low post-PCI group (20.5%) than in the high post-PCI FFR group (10.3%) (adjusted hazard ratio [HR] 2.11, 95% confidence interval [CI] 1.56-2.86, p<0.001). The cumulative incidence of cardiac death or TVMI was also significantly higher in the low post-PCI FFR group (7.3%) than in the high post-PCI FFR group (3.2%) (adjusted HR 2.34, 95% CI 1.12-4.91, p=0.024). Landmark analysis at 2 years showed that the impact of post-PCI FFR on TVF was consistently found during the first 2 years (adjusted HR of low post-PCI FFR 2.22, 95% CI 1.54-3.21, p<0.001) and thereafter (adjusted HR of low post-PCI FFR 1.96, 95% CI 1.14-3.36, p<0.001). However, the impact of post-PCI FFR on cardiac death or TVMI was more significant after 2 years of follow-up (adjusted HR of low post-PCI FFR 2.01, 95% CI 0.66-6.11, p=0.217 for the first 2 years and adjusted HR of low-post PCI FFR 2.81, 95% CI 1.04-7.60, p=0.042). The cumulative incidence of TVR was 9.5% for 5 years, and 61.0% of TVRs occurred in the stented segment. However, the proportion of TVRs in the non-stented segment increased along with the decrease of post-PCI FFR (35.3% in post-PCI FFR more than 0.90, 34.1% in post-PCI FFR 0.81-0.90, 43.8% in post-PCI FFR 0.71-0.80, and 66.7% in post-PCI FFR 0.70 and less than 0.70, p-for trend<0.001). Conclusions The long-term outcome results of the Internation Post-PCI FFR Extended registry showed that the prognostic impact of post-PCI FFR on TVF was consistently found along with the follow-up. However, that of post-PCI FFR on cardiac death or TVMI was more prominent during the late period of follow-up. In addition, clinical event distribution was different according to post-PCI FFR values.

TCT-259 Lack of Utility of Post-Stenting Fractional Flow Reserve After Imaging-Guided Stenting

TCT-259 Lack of Utility of Post-Stenting Fractional Flow Reserve After Imaging-Guided Stenting

Differential Prognostic Implications of Pre- and Post-Stent Fractional Flow Reserve in Patients Undergoing Percutaneous Coronary Intervention.

The influence of pre-intervention coronary physiologic status on outcomes post percutaneous coronary intervention (PCI) is not well known. We sought to investigate the prognostic implications of pre-PCI fractional flow reserve (FFR) combined with post-PCI FFR. A total of 1,479 PCI patients with pre-and post-PCI FFR data were analyzed. The patients were classified according to the median values of pre-PCI FFR (0.71) and post-PCI FFR (0.88). The primary outcome was target vessel failure (TVF) at 2 years. The risk of TVF was higher in the low pre-PCI FFR group than in the high pre-PCI FFR group (hazard ratio, 1.82; 95% confidence interval, 1.15-2.87; p=0.011). In 4 group comparisons, the cumulative incidences of TVF at 2 years were 3.8%, 4.1%, 4.8%, and 10.2% in the high pre-/high post-, low pre-/high post-, high pre-/low post-, and low pre-/low post-PCI FFR groups, respectively. The risk of TVF was the highest in the low pre-/low post-PCI FFR group among the groups (p values for comparisons <0.05). In addition, the high pre-/low post-PCI FFR group presented a comparable risk of TVF with the high post-PCI FFR groups (p values for comparison >0.05). When the prognostic value of the post-PCI FFR was evaluated according to the pre-PCI FFR, the risk of TVF significantly decreased with an increase in post-PCI FFR in the low pre-PCI FFR group, but not in the high pre-PCI FFR group. Pre-PCI FFR was associated with clinical outcomes after PCI, and the prognostic value of post-PCI FFR differed according to the pre-PCI FFR. ClinicalTrials.gov Identifier: NCT04012281.

Post-stenting fractional flow reserve vs coronary angiography for optimization of percutaneous coronary intervention (TARGET-FFR).

Aims A fractional flow reserve (FFR) value ≥0.90 after percutaneous coronary intervention (PCI) is associated with a reduced risk of adverse cardiovascular events. TARGET-FFR is an investigator-initiated, single-centre, randomized controlled trial to determine the feasibility and efficacy of a post-PCI FFR-guided optimization strategy vs. standard coronary angiography in achieving final post-PCI FFR values ≥0.90.Methods and results After angiographically guided PCI, patients were randomized 1:1 to receive a physiology-guided incremental optimization strategy (PIOS) or a blinded coronary physiology assessment (control group). The primary outcome was the proportion of patients with a final post-PCI FFR ≥0.90. Final FFR ≤0.80 was a prioritized secondary outcome. A total of 260 patients were randomized (131 to PIOS, 129 to control) and 68.1% of patients had an initial post-PCI FFR <0.90. In the PIOS group, 30.5% underwent further intervention (stent post-dilation and/or additional stenting). There was no significant difference in the primary endpoint of the proportion of patients with final post-PCI FFR ≥0.90 between groups (PIOS minus control 10%, 95% confidence interval −1.84 to 21.91, P = 0.099). The proportion of patients with a final FFR ≤0.80 was significantly reduced when compared with the angiography-guided control group (−11.2%, 95% confidence interval −21.87 to −0.35], P = 0.045).Conclusion Over two-thirds of patients had a physiologically suboptimal result after angiography-guided PCI. An FFR-guided optimization strategy did not significantly increase the proportion of patients with a final FFR ≥0.90, but did reduce the proportion of patients with a final FFR ≤0.80.

Impact of Poststenting Fractional Flow Reserve on Long-Term Clinical Outcomes: The FFR-SEARCH Study.

[Figure: see text].

Insufficient recovery of fractional flow reserve even after optimal implantation of drug-eluting stents: 3-year outcomes from the FUJI study

BackgroundAdequate improvement in fractional flow reserve (FFR) is not necessarily achieved in some cases of drug-eluting stent (DES) implantation, even when imaging confirms successful placement. We hypothesized that post-stent FFR may be associated with advanced diffuse atherosclerotic condition. We explored the relationships between FFR values after DES implantation (post-stent FFR). MethodsA total of 218 patients were included in this prospective, multicenter study and were divided into two groups: adequate FFR group (post-stent FFR >0.80, n=176) and inadequate FFR group (post-stent FFR ≤0.80, n=42). The primary endpoint was a major adverse cardiovascular event (MACE) including cardiac death, non-fatal myocardial infarction (MI), unplanned coronary revascularization, and hospitalization for heart failure. The secondary endpoints were event rate of all-cause death, non-fatal MI, unplanned coronary revascularization, non-fatal stroke, and hospitalization for heart failure. ResultsDuring follow-up of 31.4±8.7 months, 34 patients (16%) had cardiovascular events. Inadequate FFR group was significantly associated with higher risk of MACE (hazard ratio: 3.86; 95% confidence interval: 1.17–12.76, p=0.026; log-rank p=0.027). In particular, the incidence of unplanned coronary revascularization on non-target lesions was significantly higher in the inadequate FFR group (log-rank p=0.031). ConclusionsPost-stent FFR ≤0.80 was associated with a high incidence of non-target lesion revascularization and could be a surrogate marker for advanced atherosclerotic condition in the vessels of the entire coronary artery.

Role of Post-Stent Physiological Assessment in a Risk Prediction Model After Coronary Stent Implantation

ObjectivesThe aim of this study was to develop a risk model incorporating clinical, angiographic, and physiological parameters to predict future clinical events after drug-eluting stent implantation. BackgroundPrognostic factors after coronary stenting have not been comprehensively investigated. MethodsA risk model to predict target vessel failure (TVF) at 2 years was developed from 2,200 patients who underwent second-generation drug-eluting stent implantation and post-stent fractional flow reserve (FFR) measurement. TVF was defined as a composite of cardiac death, target vessel myocardial infarction, and clinically driven target vessel revascularization. A random survival forest model with automatic feature selection by minimal depth analysis was used for risk model development. ResultsDuring 2 years of follow-up, the cumulative incidence of TVF was 5.9%. From clinical, angiographic, and physiological parameters, 6 variables were selected for the risk model in order of importance within the model as follows: total stent length, post-stent FFR, age, post-stent percentage diameter stenosis, reference vessel diameter, and diabetes mellitus. Harrell’s C index of the random survival forest model was 0.72 (95% confidence interval [CI]: 0.62 to 0.82). This risk model showed better prediction ability than models with clinical risk factors alone (Harrell’s C index = 0.55; 95% CI: 0.41 to 0.59; p for comparison = 0.005) and with clinical risk factors and angiographic parameters (Harrell’s C index = 0.65; 95% CI: 0.52 to 0.77; p for comparison = 0.045). When the patients were divided into 2 groups according to the median of total stent length (30 mm), post-stent FFR and total stent length showed the highest variable importance in the short- and long-stent groups, respectively. ConclusionsA risk model incorporating clinical, angiographic, and physiological predictors can help predict the risk for TVF at 2 years after coronary stenting. Total stent length and post-stent FFR were the most important predictors. (International Post PCI FFR Registry; NCT04012281)

Validation of post-stenting fractional flow reserve with intravascular ultrasound parameters for optimal stent deployment.

We aimed to evaluate the relationship between post-stent fractional flow reserve (FFR) and intravascular ultrasound (IVUS) parameters for stent optimization. IVUS and FFR measurements were performed in 101 coronary lesions after successful percutaneous coronary intervention (PCI). Quantitative IVUS parameters for stent optimization such as minimal intra-stent cross sectional area (CSA), proximal, and distal reference lumen CSA, and plaque burden (PB) at both edges of the stent related to the post-stent FFR. Mean post-stent FFR was 0.91 ± 0.06. Post-stent FFR ≤ 0.90 was observed in 46 (45.5%) lesions. The 55 lesions with post-stent FFR > 0.9 had larger proximal CSA (9.2 ± 2.9mm2 vs. 7.4 ± 2.3mm2, p = 0.001), distal reference lumen CSA (7.4 ± 2.7mm2 vs. 6.3 ± 2.1mm2, p = 0.017), minimum intra-stent lumen CSA (7.4 ± 2.5mm2 vs. 6.1 ± 1.7mm2, p = 0.004), and lower proximal reference PB (45 ± 8.2% vs. 50 ± 11%, p = 0.017) than did those with post-stent FFR ≤ 0.90. Post-stent FFR had an inverse correlation with age, left anterior descending artery (LAD) against non-LAD, and proximal reference PB and a positive correlation with pre-stent FFR, proximal and distal reference lumen CSA, and minimum intra-stent lumen CSA. Meanwhile, no correlation was found between post-stent FFR and stent length. Pre-stent FFR (β = 0.544), proximal reference lumen CSA (β = 0.530) and age (β = - 0.251) were found to be independently associated with the post-stent FFR. Post-procedural FFR might partly reflect the appropriateness of PCI results in terms of the adequate expansion of the stent and full lesion coverage on IVUS.

Incremental Prognostic Value of Post-Intervention Pd/Pa in Patients Undergoing Ischemia-Driven Percutaneous Coronary Intervention

ObjectivesThis study sought to evaluate the prognostic value of post–percutaneous coronary intervention (PCI) distal coronary pressure to aortic pressure ratio (Pd/Pa) in predicting long-term clinical outcomes and to determine whether Pd/Pa combined with fractional flow reserve (FFR) post-intervention provides additional prognostic information superior to either marker alone. BackgroundPost-PCI FFR has been shown to be a predictor of long-term outcomes in numerous studies. The role of post-PCI resting Pd/Pa has not been previously studied in this setting. MethodsConsecutive patients undergoing PCI who had pre- and post-PCI Pd/Pa and FFR were followed for major adverse cardiovascular events (MACE) including death, myocardial infarction, and target vessel revascularization. ResultsA total of 574 patients were followed for 30 months (25th to 75th percentile 18 to 46 months). Using receiver-operating characteristic curve analysis post-stenting FFR cutoff of ≤0.86 had the best predictive accuracy of MACE (17% vs. 23%; log-rank p = 0.02), whereas post-stenting Pd/Pa ≤0.96 was the best predictor of MACE (15% vs. 24%; log rank p = 0.0006). There was a significant interaction between post-PCI Pd/Pa and FFR on MACE risk such that patients with Pd/Pa ≤0.96 and FFR ≤0.86 had the highest event rate (25%), whereas those with Pd/Pa >0.96 and FFR >0.86 had the lowest event rate (15%), which was not different from patients with Pd/Pa >0.96 and FFR ≤0.86 (17%). In a fully adjusted Cox regression analysis, Pd/Pa was an independent predictor of MACE (hazard ratio: 2.07; 95% confidence interval: 1.3 to 3.3; p = 0.002). ConclusionsPost-PCI resting Pd/Pa is a powerful prognostic tool for MACE prediction. It adds complementary and incremental risk stratification over established factors including post-PCI FFR.

100.02 Correlation Between Fraction Flow Reserve Variation and Optical Coherence Tomography Imaging Post-Stenting Optimization: Results from ILUMIEN-I Trial

Fractional flow reserve (FFR) is a reliable and reproducible invasive method to assess coronary ischemia due to its physiologic approach. Some studies found that post stenting FFR above 0.90 predicts good outcomes, but thin assessment reflects a vessel level, providing limited information regarding

New Volumetric Analysis Method for Stent Expansion and its Correlation With Final Fractional Flow Reserve and Clinical Outcome: An ILUMIEN I Substudy

ObjectivesThis study sought to compare conventional methodology (CM) with a newly described optical coherence tomography (OCT)-derived volumetric stent expansion analysis in terms of fractional flow reserve (FFR)-derived physiology and device-oriented composite endpoints (DoCE). BackgroundThe analysis of coronary stent expansion with intracoronary imaging has used CM that relies on the analysis of selected single cross-sections for several decades. The introduction of OCT with its ability to perform semiautomated volumetric analysis opens opportunities to redefine optimal stent expansion. MethodsA total of 291 lesions treated with post-stent OCT and FFR were enrolled. The expansion index was calculated by using a novel volumetric algorithm and was defined as: ([actual lumen area / ideal lumen area] × 100) for each frame of the stented segment. The minimum expansion index (MEI) was defined as the minimum value of expansion index along the entire stented segment. MEI and conventional lumen expansion metrics were compared for the ability to predict post-stent low FFR (<0.90) and DoCE at 1 year. ResultsThere was a stronger correlation between MEI and final FFR, compared with CM and final FFR (r = 0.690; p < 0.001) versus (r = 0.165; p = 0.044). MEI was significantly lower in patients with DoCE than those without DoCE (72.18 ± 8.23% vs. 81.48 ± 11.03%; p < 0.001), although stent expansion by CM was similar between patients with and without DoCE (85.05 ± 22.19% and 83.73 ± 17.52%; p = 0.858), respectively. ConclusionsOCT analysis of stent expansion with a newly described volumetric method, but not with CM, yielded data that were predictive of both an acute improvement in FFR-derived physiology and DoCE.

In vivo validation of mathematically derived fractional flow reserve for assessing haemodynamics of coronary tandem lesions.

Our aim was to propose a prediction model for the post-stenting fractional flow reserve (FFR'd,pred) at a position distal to the tandem lesion. Using the FFR at a position proximal to the tandem lesion (FFRp), and the FFR gradients across proximal (ΔFFRp) and distal (ΔFFRd) stenoses, FFR'd,pred after treating either the distal or proximal lesion was predicted as FFRp-ΔFFRp/(1-1.33kΔFFRd) or FFRp-ΔFFRd/(1-1.33ΔFFRp), respectively. The flow fraction of the distal main branch (k) was estimated using the diameter ratio of side to distal main branches. For in vivo validation, 50 patients with a tandem lesion (diameter stenosis >50%) were evaluated. Compared to the conventional model that did not consider side branch flow, our predicted FFR showed closer correlation with the measured FFR (R2=0.83 vs. 0.57) and significant reduction in mean absolute errors (0.034±0.028 vs. 0.053±0.049, p<0.001). In particular, with a large side branch and low baseline FFR, decision making using the current model had greater predictive ability than with the conventional model. By predicting which stenosis is more severe and/or whether the remaining lesion after the first treatment is functionally significant, a tandem prediction model can help to plan optimised stent implantation.

Impact of lesion characteristics on the prediction of optimal poststent fractional flow reserve

Poststent fractional flow reserve (FFR) is a useful indicator of optimal percutaneous coronary intervention, and higher poststent FFR is associated with favorable long-term clinical outcome. However, little is known about the factors influencing poststent FFR. The purpose of this study was to determine the impact of lesion characteristics on poststent FFR. For patients who had scheduled stent implantation for stable angina, FFR measurements at maximum hyperemia were performed before and after coronary stent implantation. As one of lesion characteristics, the FFR pressure drop pattern was evaluated and classified as either an abrupt or a gradual pattern according to the pullback curve of FFR. A total of 205 lesions with physiological significant stenosis were evaluated. Fractional flow reserve value increased from 0.67±0.10 to 0.87±0.07 after stent implantation. Optimal poststent FFR was achieved in 75 lesions (36.6%). Logistic regression analysis demonstrated that optimal poststent FFR was positively correlated with an abrupt pressure drop pattern (hazard ratio [HR] 2.11, 95% CI 1.06-4.15, P=.03) and prestent FFR (HR 1.04, 95% CI 1.03-2.04, P=.03; per 0.1 increase), and negatively correlated with lesion localization to the left anterior descending artery (HR 0.18, 95% CI 0.09-0.36, P<.0001). The c statistic for predicting optimal poststent FFR was 0.763 (95% CI 0.702-0.819). Abrupt pressure drop patterns, prestent FFR, and lesion localization to the left anterior descending artery were independent predictors of optimal poststent FFR.

Ability of Fractional Flow Reserve to Predict Restenosis After Superficial Femoral Artery Stenting

Purpose: To evaluate the clinical efficacy of poststenting fractional flow reserve (FFR) in terms of predicting restenosis in superficial femoral artery (SFA) disease. Methods: This prospective, single-center, nonrandomized study enrolled 48 patients (mean age 76±9 years; 38 men) with 51 SFA lesions from July 2013 to June 2014. Mean FFR (distal mean pressure/proximal mean pressure) and systolic FFR (distal systolic pressure/proximal systolic pressure) were calculated, and the relationship between these FFR values and restenosis at 12 months was investigated using receiver operating characteristic (ROC) curve analysis. Results: Poststenting FFR was significantly lower in the restenosis group (poststenting mean FFR 0.85±0.07 vs 0.93±0.05, p=0.001; poststenting systolic FFR 0.76±0.14 vs 0.87±0.08, p=0.015). The area under the ROC curve for restenosis in poststenting mean FFR was higher, but not statistically significant, than that in poststenting systolic FFR (0.84 vs 0.74, p=0.08). The best poststenting mean FFR cutoff value for predicting restenosis was 0.92 (sensitivity 0.64, specificity 0.91). The 4.5% restenosis rate at 12 months in the high (>0.92) poststenting mean FFR group was significantly lower (35.7%, p=0.008) than in the low (≤0.92) poststenting mean FFR group. Conclusion: Poststenting mean FFR is useful for predicting restenosis in SFA disease.

The Value of Pre- and Post-Stenting Fractional Flow Reserve for Predicting Mid-Term Stent Restenosis Following Percutaneous Coronary Intervention (PCI).

Measuring fractional flow reserve (FFR) in percutaneous coronary intervention (PCI) has predictive value for PCI outcome. We decided to examine the utility of pre- and post-stenting FFR as a predictor of 6-month stent restenosis as well as MACE (major adverse cardiac events). Pre- and post-stenting FFR values were measured for 60 PCI patients. Within 6 months after stenting, all patients were followed for assessment of cardiac MACE including myocardial infarction, unstable angina, or positive exercise test. Stent restenosis was also assessed. Cut-off values for pre- and post-stenting FFR measurements were considered respectively as 0.65 and 0.92. Stent restenosis was detected in 4 patients (6.6%). All 4 patients (100%) with restenosis had pre-stenting FFR of < 0.65, while only 26 of 56 patients without restenosis (46.4%) had pre-stenting FFR value of < 0.65 (P = 0.039). Mean pre-stenting FFR in patients with restenosis was significantly lower than in those without restenosis (0.25 ± 0.01 vs. 0.53 ± 0.03, P = 0.022). Although stent restenosis was higher in patients with post-stenting FFR of < 0.92 (2 cases, 9.5%) than in those with FFR value of ≥ 0.92 (2 cases, 5.1%), the difference was not statistically (P = 0.510). Pre-stenting FFR, the use of longer stents, and history of diabetes mellitus can predict stent restenosis, but the value of post-stenting FFR for predicting restenosis was not explicit.

Association of moderate chronic kidney disease with insufficient improvement of fractional flow reserve after stent implantation.

This study aims to investigate the association of moderate chronic kidney disease (CKD) with fractional flow reserve (FFR) after stent implantation. Patients with moderate CKD have a higher prevalence of severe and diffuse coronary artery disease, and have increased risk of cardiovascular events even after stent implantation. On the other hand, in some patients, FFR could not be sufficiently improved even after stent implantation. However, the association between these pathophysiological processes is unclear. A total of 102 patients with stable angina, in whom a stent was implanted for the left anterior descending coronary artery (LAD) lesion, were included. Patients with a severely decreased glomerular filtration rate (GFR; > CKD stage 4) were excluded. Patients were stratified into 3 groups: those with an estimated GFR (eGFR) ≥ 60 mL per min per 1.73 m(2) (stage 0-2), 45 to 59 mL per min per 1.73 m(2) (stage 3a), and 30 to 44 mL per min per 1.73 m(2) (stage 3b). FFR after stent implantation (post-stent FFR) was significantly lower in the stage 3b group than in both the stage 0-2 group and the stage 3a group (P < 0.01). Post-stent FFR had a significant positive correlation with eGFR (r = 0.223, P = 0.024). Multivariate analysis demonstrated that eGFR was an independent predictor of post-stent FFR. Moderate CKD was independently associated with insufficient improvement of FFR after stent implantation. This can partly explain the poor prognosis of patients with CKD. © 2015 Wiley Periodicals, Inc.

CLINICAL AND PROGNOSTIC VALUE OF POST STENTING FFR FOR ASSESSMENT OF ISCHEMIA REDUCTION IN PATIENTS WITH ACUTE CORONARY SYNDROMES

Measuring fractional flow reserve (FFR) in acute coronary syndromes (ACS) is seldom employed given concerns about possible impaired microvascular function. The importance of ischemic reduction assessed by post-stenting FFR (PS-FFR) and its impact on long term outcomes has not been studied in this

TCT-333 Clinical Relevance of Post-Stent Fractional Flow Reserve after Drug-Eluting Stent Implantation

TCT-333 Clinical Relevance of Post-Stent Fractional Flow Reserve after Drug-Eluting Stent Implantation

Relationship between fractional flow reserve and residual plaque volume and clinical outcomes after optimal drug-eluting stent implantation: Insight from intravascular ultrasound volumetric analysis

BackgroundThe underlying cause of FFR reduction and prognostic impact of FFR after optimal DES implantation remain unknown. The study aims were to use intravascular ultrasound (IVUS) to investigate the mechanism responsible for reduced fractional flow reserve (FFR) after optimal drug-eluting stent (DES) implantation and to evaluate FFR effect on clinical outcomes after optimal percutaneous coronary intervention with DES. MethodsNinety-seven patients treated with optimal DES implantation under IVUS and pullback FFR guidance were followed clinically (median 17.8months). Post-stenting IVUS examination and pullback FFR recording were performed, and angiographic and IVUS parameters associated with reduced FFR were evaluated. The composite of major adverse cardiac events (MACE), including cardiac death, myocardial infarction, stent thrombosis, and target vessel revascularization, was analyzed. ResultsRegression analysis showed inverse correlations between post-stent FFR and residual plaque volume index (r=−0.40, p<0.01) and residual percent plaque volume (r=−0.68, p<0.01) in IVUS but no correlation of minimal lesion diameter with quantitative coronary angiography (r=0.07, p=0.50) or IVUS-derived minimal stent area (r=0.02, p=0.84). MACE was observed in 10 patients (10.3%), and FFR after optimal stenting was significantly lower in this group (0.86±0.04 vs 0.91±0.04, p<0.01). The optimal FFR threshold for predicting MACE was 0.90, identified by the receiver operating characteristic curve. ConclusionsReduced FFR after optimal DES implantation was associated with residual plaque volume identified by IVUS and future adverse cardiac events.

Functional and morphological assessment of side branch after left main coronary artery bifurcation stenting with cross‐over technique

In left main coronary artery (LMCA) bifurcation lesions, hemodynamic and geometrical change in left circumflex artery (LCX) ostium after main branch (MB) stenting has not been known. This study evaluated how accurately intravascular ultrasound (IVUS) predicts the functional compromise of the sidebranch. A single-stent cross-over technique was used to treat LMCA bifurcation lesions in 43 patients with LCX ostial diameter stenosis (DS) of <50%. The fractional flow reserve (FFR) in the LCX was measured after MB stenting, MB and sidebranch pullback IVUS was performed prestenting and poststenting. After MB stenting, angiographic DS >50% at the LCX ostium was observed in 18 (42%) patients, while only 3 (7%) showed FFR <0.80. A pre-procedural minimal lumen area (MLA) of <3.7 mm(2) within the LCX ostium was predictive of a poststenting FFR <0.80, with a sensitivity of 100%, specificity of 71%, a positive predictive value (PPV) of 16%, and a negative predictive value (NPV) of 100% (area under curve 0.80, P < 0.001). Moreover, pre-procedural plaque burden of >56% at the LCX ostium predicted FFR <0.80, with a sensitivity of 100%, specificity of 65%, a PPV of 14%, and a NPV of 100% (area under curve 0.80, P < 0.001). A poststenting LCX ostial DS >57% predicted FFR <0.80 with a sensitivity of 100%, specificity of 88%, a PPV of 38% and a NPV of 100% (area under curve 0.962, P < 0.001). However, the poststenting MLA within the LCX ostium showed no significant correlation with FFR (r = 0.197, P = 0.391). In LMCA bifurcation lesions with mild LCX ostial disease, the use of single-stent technique rarely resulted in the functional LCX compromise. Because the functional LCX stenosis is poorly predicted by a small MLA, sidebranch treatment should be based on the poststenting FFR.