Pre-Procedural Assessment of the Femoral Access Route for Transcatheter Aortic Valve Implantation: Comparison of a Non-Contrast Time-of-Flight Magnetic Resonance Angiography Protocol with Contrast-Enhanced Dual-Source Computed Tomography Angiography.

Background: We aimed to evaluate the feasibility of a non-contrast time-of-flight magnetic resonance angiography (TOF-MRA) protocol for the pre-procedural access route assessment of transcatheter aortic valve implantation (TAVI) in comparison with contrast-enhanced cardiac dual-source computed tomography angiography (CTA). Methods and Results: In total, 51 consecutive patients (mean age: 82.69 ± 5.69 years) who had undergone a pre-TAVI cardiac CTA received TOF-MRA for a pre-procedural access route assessment. The MRA image quality was rated as very good (median of 5 [IQR 4-5] on a five-point Likert scale), with only four examinations rated as non-diagnostic. The TOF-MRA systematically underestimated the minimal effective vessel diameter in comparison with CTA (for the effective vessel diameter in mm, the right common iliac artery (CIA)/external iliac artery (EIA)/common femoral artery (CFA) MRA vs. CTA was 8.04 ± 1.46 vs. 8.37 ± 1.54 (p < 0.0001) and the left CIA/EIA/CFA MRA vs. CTA was 8.07 ± 1.32 vs. 8.28 ± 1.34 (p < 0.0001)). The absolute difference between the MRA and CTA was small (for the Bland-Altman analyses in mm, the right CIA/EIA/CFA was -0.36 ± 0.77 and the left CIA/EIA/CFA was -0.25 ± 0.61). The overall correlation between the MRA and CTA measurements was very good (with a Pearson correlation coefficient of 0.87 (p < 0.0001) for the right CIA/EIA/CFA and a Pearson correlation coefficient of 0.9 (p < 0.0001) for the left CIA/EIA/CFA). The feasibility agreement between the MRA and CTA for transfemoral access was good (the right CIA/EIA/CFA agreement was 97.9% and the left CIA/EIA/CFA agreement was 95.7%, Kohen's kappa: 0.477 (p = 0.001)). Conclusions: The TOF-MRA protocol was feasible for the assessment of the access route in an all-comer pre-TAVI population. This protocol might be a reliable technique for patients at an increased risk of contrast-induced nephropathy.

Assessment of Impact of Patient Recruitment Volume on Risk Profile, Outcomes, and Treatment Effect in a Randomized Trial of Ticagrelor Versus Prasugrel in Acute Coronary Syndromes.

BACKGROUND Whether there are differences in the risk profile and treatment effect in patients recruited in a low recruitment center (LRC) versus patients recruited in a high recruitment center (HRC) in a randomized multicenter trial remains unknown. METHODS AND RESULTS This study included 4018 patients with acute coronary syndrome recruited in the ISAR-REACT 5 (Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 5) trial. The primary end point was a composite of all-cause death, myocardial infarction, or stroke. Overall, 3011 patients (75%) were recruited in the HRCs (7 centers recruiting 258 to 628 patients; median, 413 patients) and 1007 patients (25%) were recruited in the LRCs (16 centers recruiting 5 to 201 patients; median, 52 patients). Patients recruited in the LRCs had more favorable cardiovascular risk profiles than patients recruited in the HRCs. The primary end point occurred in 72 patients in the LRCs and 249 patients in the HRCs (cumulative incidence, 7.3% and 8.4%; P=0.267). All-cause mortality was lower among patients recruited in the LRCs (n=29) than among patients recruited in the HRCs (n=134; cumulative incidence 2.9% versus 4.5%; P=0.031). There was no significant interaction between the treatment effect of ticagrelor versus prasugrel and patient recruitment category (LRC versus HRC) regarding the primary efficacy end point (LRC: hazard ratio [HR], 1.42 [95% CI, 0.89-2.28]; HRC: HR, 1.33 [95% CI, 1.04-1.72]; P for interaction=0.800). CONCLUSIONS Patients with acute coronary syndrome recruited in a LRC appear to have more favorable cardiovascular risk profiles and lower 1-year mortality rates compared with patients recruited in a HRC. The recruitment volume did not interact with the treatment effect of ticagrelor versus prasugrel. REGISTRATION URL: https://www.clinicaltrials.gov; Unique identifier: NCT01944800.

Design and rationale of the XIENCE short DAPT clinical program: An assessment of the safety of 3-month and 1-month DAPT in patients at high bleeding risk undergoing PCI with an everolimus-eluting stent.

Dual antiplatelet therapy (DAPT) is key for the prevention of recurrent ischemic events after percutaneous coronary intervention (PCI); however, it increases the risk of bleeding complications. While new generation drug-eluting stents have been shown superior to bare-metal stents after a short DAPT course, the optimal DAPT duration in patients at high bleeding risk (HBR) remains to be determined. TRIAL DESIGN: The XIENCE Short DAPT program consists of three prospective, single-arm studies (XIENCE 90, XIENCE 28 Global and XIENCE 28 USA) investigating 3- or 1-month DAPT durations in HBR patients undergoing PCI with the XIENCE stent. The XIENCE 90 study is being conducted in the US and enrolled 2047 subjects who discontinued DAPT at 3 months if they were free from myocardial infarction (MI), repeat coronary revascularization, stroke, or stent thrombosis. The XIENCE 28 program includes the USA study, enrolling 642 patients in US and Canada, and the Global study, enrolling 963 patients in Europe and Asia. In XIENCE 28, patients were to discontinue DAPT at 1 month post-PCI if event-free. The primary hypothesis for both XIENCE 90 and XIENCE 28 is that a short DAPT regimen will be non-inferior to a conventional DAPT duration with respect to the composite of all-cause death or MI. Patients enrolled in the prospective multicenter post-market XIENCE V USA study will be used as historical control group in a stratified propensity-adjusted analysis. CONCLUSIONS: The XIENCE Short DAPT Program will provide insights into the safety and efficacy of 2 abbreviated DAPT regimens of 3- and 1-month duration in a large cohort of HBR patients undergoing PCI with the XIENCE stent.

Assessment of aortic annulus dimensions for transcatheter aortic valve replacement (TAVR) with high-pitch dual-source CT: Comparison of systolic high-pitch vs. multiphasic data acquisition.

OBJECTIVES: To evaluate a systolic ECG-gated high-pitch aortoiliac computed tomography (CT) angiography for planning transcatheter aortic valve implantation (TAVI). METHODS: Patients referred for TAVI underwent a combined CT imaging with retrospective, multiphasic ECG-gating of the heart and systolic ECG-gated high-pitch aortoiliac CT angiography. Consecutive patients were retrospectively included in this study group. Heart rate (HR) and heart rate variability (HRV) were assessed during the high-pitch ECG prediction phase. Aortic annulus area (AAA) was planimetrically quantified on both datasets. While only one moment of cardiac cycle was available for measurements in the high-pitch CT, the point of time in the multiphasic CT was chosen, where AAA yielded maximum size. Hypothetical prosthesis sizing was compared between multiphasic vs. high-pitch CT. RESULTS: Among 61 patients (44.2 % men, mean age: 83.3 ± 5.5 years) average heart rate and HRV were 71.0 ± 13.4 bpm and 7.3 ± 8.5 bpm. 20 patients (32.7 %) had atrial fibrillation at the time of image acquisition. There was a strong correlation of AAA as derived from multiphasic vs. the high-pitch CT (r = 0.98). The difference in AAA was 10.5 ± 17.1mm2 (455.1 ± 83.0 mm2 for multiphasic vs. 444.5 ± 87.2 mm2 for high-pitch CT) and did not reach statistical significance (p = 0.08). Hypothetical prosthesis sizing showed an agreement in 55 of 61 patients (90.2 %). A sizing based on the high-pitch CT resulted in smaller prosthesis choice in 6 patients, all of them suffering from atrial fibrillation. Mean effective radiation dose was 10.9 ± 6.1 mSv for cardiac CTA and 4.1 ± 1.0 mSv for high-pitch CTA. CONCLUSION: For patients with sinus rhythm, systolic high-pitch aortoiliac CTA provides adequate prosthesis size selection as compared with multiphasic ECG-gated cardiac CTA and may result in significantly reduced radiation exposition.

Fractional flow reserve-guided multivessel angioplasty in myocardial infarction: three-year follow-up with cost benefit analysis of the Compare-Acute trial.

AIMS: The Compare-Acute trial showed superiority of fractional flow reserve (FFR)-guided acute complete revascularisation compared to culprit-only treatment in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD) at one year. The aim of this study was to investigate the outcome at three years, together with cost analysis of this strategy. METHODS AND RESULTS: After primary percutaneous coronary intervention (PCI), 885 patients with STEMI and MVD were randomised (1:2 ratio) to FFR-guided complete revascularisation (295 patients) or infarct-related artery (IRA)-only treatment (590 patients). After 36 months, the primary endpoint (composite of death, myocardial infarction, revascularisation, stroke) occurred significantly less frequently in the FFR-guided complete revascularisation group: 46/295 patients (15.6%) versus 178/590 patients (30.2%) (HR 0.46, 95% CI: 0.33-0.64; p<0.001). This benefit was driven mainly by the reduction of revascularisations in the follow-up (12.5% vs 25.2%; HR 0.45, 95% CI: 0.31-0.64; p<0.001). Cost analysis shows benefit of the FFR-guided complete revascularisation strategy, which can reduce the cost per patient by up to 21% at one year (8,150€ vs 10,319€) and by 22% at three years (8,653€ vs 11,100€). CONCLUSIONS: In patients with STEMI and MVD, FFR-guided complete revascularisation is more beneficial in terms of outcome and healthcare costs compared to IRA-only revascularisation at 36 months.

Adverse events in patients with high platelet reactivity following successful chronic total occlusion PCI: The Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents (ADAPT-DES) study.

BACKGROUND: Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) typically requires a greater number of stents and longer stent length than non-CTO PCI, placing these patients at greater risk for adverse ischemic events. We sought to determine whether the association between high platelet reactivity (HPR) and the risk of ischemic events is stronger after CTO than non-CTO PCI. METHODS: Patients undergoing successful PCI in the multicenter ADAPT-DES study were stratified according to whether they underwent PCI of a CTO. HPR was defined as VerifyNow platelet reaction units >208. The study primary endpoint was the 2-year risk target vessel failure ([TVF] defined as cardiac death, myocardial infarction, or target lesion revascularization). RESULTS: CTO PCI was performed in 400 of 8448 patients. HPR was present in 34.5% of CTO PCI patients and 43.1% of non-CTO PCI patients (P = .0007). Patients undergoing CTO PCI with versus without HPR had significantly higher 2-year rates of TVF (15.0% versus 8.3%, P = .04) without significant differences in bleeding. HPR was an independent predictor of 2-year TVF (adjusted HR 1.16, 95% CI 1.02-1.34, P = .03) whereas CTO PCI was not (adjusted HR 0.89, 95% CI 0.65-1.22, P = .48). There was a significant interaction between CTO versus non-CTO PCI and PRU as a continuous variable for 2-year TVF (Pinteraction = 0.02). CONCLUSIONS: In ADAPT-DES, HPR was associated with an increased 2-year risk of TVF after PCI, an association that was at least as strong after CTO PCI compared with non-CTO PCI.

Sex differences in the effect of diabetes mellitus on platelet reactivity and coronary thrombosis: From the Assessment of Dual Antiplatelet Therapy with Drug-Eluting Stents (ADAPT-DES) study.

BACKGROUND: Whether the consequences of diabetes mellitus (DM) are worse for women than for men treated with drug-eluting stents (DES) and antiplatelet therapy remain unclear. METHODS: Patients from the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents study were stratified according to sex and DM status. We investigated the sex-specific effect of DM on high on-clopidogrel platelet reactivity (HPR), defined as a P2Y12 reaction units ≥208, and the adjusted association of DM on the 2-year risk for coronary thrombotic events (CTE), defined as spontaneous myocardial infarction or definite or probable stent thrombosis. RESULTS: Out of 8582 patients included in the study, 829 were women with DM (9.6%) and 1954 were men with DM (16.2%). The prevalence of insulin-treated DM (ITDM) was greater in women (p<0.0001). By multivariable logistic regression, DM was associated with a greater likelihood of HPR that was uniform between sexes (pint=0.88). Following adjustment for baseline variables and HPR, in women a stepwise increase in risk for CTEs was observed in the transition from no DM to non-ITDM (NITDM) (adjusted hazard ratio [adjHR]: 1.31; 95% CI: 0.78-2.18) to ITDM (adjHR: 2.69; 95% CI: 1.23-3.45). This increase in risk associated with subtypes of DM was of smaller magnitude in men (for NITDM, adjHR: 1.04; 95% CI: 0.77-1.39; for ITDM, adjHR: 1.46; 95% CI: 1.05-2.03; pint=0.016). CONCLUSIONS: In a population treated with DES and antiplatelet therapy, the risk for CTE associated with DM seems to be greater in women and was independent of HPR.

Quantifying Ischemic Risk After Percutaneous Coronary Intervention Attributable to High Platelet Reactivity on Clopidogrel (From the Assessment of Dual Antiplatelet Therapy with Drug-Eluting Stents Study).

Patients at high risk of thrombotic events after percutaneous coronary intervention (PCI) may potentially benefit from intensified antiplatelet therapy. However, more potent antiplatelet therapy would be expected to only overcome risk that is mediated by high platelet reactivity (PR). We used mediation analysis to determine the contribution of residual PR to the 2-year risk of major adverse cardiac events (MACE; the composite of cardiac death, myocardial infarction, or stent thrombosis) associated with clinical risk factors after PCI with drug-eluting stents (DES) in 8,374 patients from the prospective, multicenter Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents (ADAPT-DES) registry. Residual PR on clopidogrel, as measured by the VerifyNow P2Y12 point-of-care assay, was included as a continuous linear mediator variable in Cox proportional hazards regression. Among 7 factors independently associated with 2-year MACE, residual PR partly mediated the effect of diabetes (13.4% attributable risk), anemia (22.9% attributable risk), and acute coronary syndromes (7.3% attributable risk). A PR-mediated effect inversely affected the MACE risk associated with smoking (10.4% attributable risk). The increased ischemic risk of chronic kidney disease, multivessel disease, and previous myocardial infarction were not mediated by residual PR. In conclusion, high residual PR mediates little or none of the increased 2-year MACE risk associated with baseline risk factors in patients treated with clopidogrel after successful PCI with DES. Intensifying antiplatelet therapy is therefore unlikely to substantially mitigate the excess ischemic risk from these variables.

Sex Differences in the Clinical Impact of High Platelet Reactivity After Percutaneous Coronary Intervention With Drug-Eluting Stents: Results From the ADAPT-DES Study (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents).

BACKGROUND: Sex differences in the outcomes after percutaneous coronary intervention with drug-eluting stents and in the response to clopidogrel therapy have been reported; however, the differential risk of high platelet reactivity (HPR) on clopidogrel in women versus men is unknown. METHODS AND RESULTS: We compared 8448 patients enrolled in the ADAPT-DES study (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) according to sex and the presence/absence of HPR on clopidogrel (defined as P2Y12 reactivity units >208). Study end points were definite and probable stent thrombosis (ST), clinically relevant bleeding, all-cause mortality, myocardial infarction, and major adverse cardiac events (comprising mortality, myocardial infarction, and target lesion revascularization). HPR was more common among women (1118/2163, 51.7%) than men (2491/6285, 39.6%). HPR was associated with a roughly double risk of 1-year ST in both women and men (women with versus without HPR: 1.4% versus 0.7%; hazard ratio [HR], 2.02; 95% confidence interval [CI], 0.82-4.95; P=0.12; and men: 1.2% versus 0.5%; HR, 2.42; 95% CI, 1.36-4.30; P=0.002; Pinteraction=0.73). HPR was associated with almost half the rate of clinically relevant bleeding in women (women: HPR versus no HPR, 5.3% versus 9.8%; HR, 0.54; 95% CI, 0.40-0.74; P<0.001), whereas men had similar rates of bleeding regardless of HPR status (men: HPR versus no HPR, 5.7% versus 5.9%; HR, 0.96; 95% CI, 0.78-1.18; P=0.70; Pinteraction=0.003). In propensity-adjusted models, HPR was an independent predictor of ST and myocardial infarction in men; although both associations were nonsignificant among women, no interaction was observed in the associations between HPR and either ST or myocardial infarction. Conversely, HPR was an independent predictor of reduced bleeding only in women (women: adjusted HR, 0.58; 95% CI, 0.41-0.82; P=0.002; and men: adjusted HR, 0.83; 95% CI, 0.65-1.04; P=0.11; Pinteraction=0.01). CONCLUSIONS: In the current analysis, the associated risk of HPR for ST was similar in both sexes. However, HPR was associated with significantly reduced bleeding only among women. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00638794.

Impact of Anemia on Platelet Reactivity and Ischemic and Bleeding Risk: From the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents Study.

Anemic patients remain at increased risk of ischemic and bleeding events. Whether the effects of hemoglobin levels on thrombotic and bleeding risk are independent of platelet reactivity on clopidogrel, however, remains unknown. Patients from the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents study were categorized by the presence of anemia at baseline, defined according the World Health Organization criteria. Platelet reactivity was measured with VerifyNow assay; high platelet reactivity (HPR) on clopidogrel was defined as platelet reactive units value >208. Of 8,413 patients included in the study cohort, 1,816 (21.6%) had anemia. HPR was more prevalent in patients with anemia (58.3% vs 38.4%; p <0.001), an association that persisted after multivariate adjustment (adjusted odds ratio: 2.04; 95% confidence interval [CI]: 1.82 to 2.29; p <0.0001). Patients with anemia had higher 2-year rates of major adverse cardiac events (9.5% vs 5.6%; p <0.0001), major bleeding (11.8% vs 7.7%; p <0.0001), and all-cause mortality (4.0% vs 1.4%; p <0.0001); however, after adjustment for baseline clinical confounders, including HPR, anemia was no longer significantly associated with major adverse cardiac events but was still independently associated with all-cause mortality (adjusted HR 1.61, 95% CI 1.23 to 2.12; p <0.0001) and major bleeding (adjusted HR 1.42, 95% CI 1.20 to 1.68; p <0.0001). The effect of HPR on clinical outcomes was uniform according to anemia status, without evidence of interaction. In conclusion, anemia independently correlated with HPR. After percutaneous coronary intervention with drug-eluting stents, anemia at baseline was significantly associated with higher 2-year hemorrhagic and mortality risk; conversely, its association with ischemic risk was attenuated after multivariate adjustment, including HPR.

Relation Between Platelet Count and Platelet Reactivity to Thrombotic and Bleeding Risk: From the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents Study.

Whether the association between platelet count (PC) and thrombotic and bleeding risk is independent of or varies by residual platelet reactivity to antiplatelet therapies is unclear. We sought to investigate the independent and combined effects of PC and platelet reactivity on thrombotic and bleeding risk after coronary artery implantation of drug-eluting stents (DES). Patients enrolled in the prospective, multicenter Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents study were stratified by PC tertiles. The study cohort comprised 8,402 patients. By linear regression analysis, lower PC was strongly and independently associated with higher platelet reactive units (PRUs) on clopidogrel. After multivariable adjustment (including PRU and aspirin reactive units), high, but not low, PC tertile was independently associated with higher risk of thrombotic complications, including spontaneous myocardial infarction and stent thrombosis. Although no independent association was observed between PC tertiles and hemorrhagic risk, both high and low PC tertiles were associated with increased risk for all-cause mortality. After stratification of PC tertiles by tertiles of PRUs, the crude risk of thrombotic complications was highest in patients in the high PC and high PRU tertiles. By multivariable adjustment, PRU increases were uniformly associated with higher risk of thrombotic events across PC tertiles, without evidence of interaction. In conclusion, higher PCs and higher PRUs act independently and synergistically in determining thrombotic risk. Alongside PRU, PCs could be a simple hematological parameter to consider for risk stratification and in tailoring duration and potency of pharmacologic platelet inhibition after DES implantation.

Pre-procedural assessment of aortic annulus dimensions for transcatheter aortic valve replacement: comparison of a non-contrast 3D MRA protocol with contrast-enhanced cardiac dual-source CT angiography.

AIMS: To evaluate the feasibility of a non-contrast three-dimensional (3D)-FLASH magnetic resonance angiography (MRA) protocol for pre-procedural aortic annulus assessment for transcatheter aortic valve replacement (TAVR) in comparison with cardiac dual-source computed tomography angiography (CTA). METHODS AND RESULTS: In this prospective study, 69 of 104 consecutive patients (mean age 81.8 ± 5.4 years, 37.7% arrhythmic) with severe aortic stenosis who had undergone pre-TAVR cardiac CTA received a respiratory and ECG-triggered, non-contrast 3D-FLASH MRA at 3 T. Annular area measurements were obtained at mid-diastole for both modalities whereas maximum systolic area was assessed by CTA only. Systolic MRA dimensions were modelled, by adding the relative difference of systolic and diastolic CTA area dimensions as a corrective factor. Hypothetical prosthesis sizing was performed based on systolic CTA, diastolic, and modelled systolic MRA area measurements. MR image quality and degree of annular calcifications were evaluated using 4-point-grading scales. The mean acquisition time was 14 ± 4.2 min. The mean image quality was 3.1 ± 0.9 with only two examinations rated non-diagnostic. The mean degree of calcifications was equal. As assessed by Bland-Altman analysis, there was no relevant systematic difference between area measurements for modelled systolic MRA and systolic CTA [the mean difference -3.1 mm(2) (limits of agreement -44.4 mm(2); 38.2 mm(2))]. Agreement for hypothetical prosthesis sizing was found in 63 of 67 (94%) patients for systolic CTA and modelled systolic MRA. CONCLUSION: The employed non-contrast 3D-FLASH MRA protocol allows for reliable assessment of aortic annulus dimensions and calcifications even in the presence of arrhythmias in an all-comers pre-TAVR population. Implementation of this technique appears legitimate in patients at an increased risk for contrast-induced nephropathy.

Duplex ultrasound assessment of native stenoses in the superficial femoral and popliteal arteries: a comparative study examining the influence of multisegment lesions.

PURPOSE: To evaluate duplex ultrasonography (DUS) in the assessment of femoropopliteal stenoses comparing a single native stenosis (SNS) to multisegmental native stenoses (MNS). METHODS: Among the 1284 patients treated for atherosclerotic occlusive disease involving the femoropopliteal segment between November 2002 and November 2012, 139 patients (97 men; mean age 68±8 years) with 142 SNS or 143 MNS in 79 and 60 patients, respectively, were eligible for this retrospective analysis. The peak systolic velocity ratios with proximal (PSVRprox) and distal (PSVRdist) reference for the 285 lesions were compared with their respective angiographic stenosis grade as measured by 2 independent readers using quantitative vascular analysis to ensure objectivity. Receiver operating characteristic curve analysis was used to evaluate sensitivity, specificity, and the optimal thresholds of PSV and PSVR for detection of stenoses by grade (>50%, >70%, or >80% diameter stenosis). The area under the curve (AUC) values of dependent and independent receiver operating characteristic curves were compared. RESULTS: For SNS, correlation of PSVRprox to diameter stenosis (R=0.88) was higher (p<0.001) than the correlation for MNS (R=0.78). In the SNS group, the AUC for detecting a >50% (0.99±0.01), >70% (0.98±0.01), and >80% (0.96±0.01) stenosis with PSVRprox was significantly higher than in the MNS group [AUC50% 0.93±0.02 (p=0.01), AUC70% 0.92±0.02 (p=0.02), and AUC80% 0.87±0.03 (p=0.003)]. The optimal thresholds for detecting >50%, >70%, and >80% stenoses for SNS using PSVRprox were 2.6, 3.3, and 3.9, respectively. For MNS, the optimal thresholds of PSVRprox were 2.6, 3.4, and 3.9, respectively, with respective sensitivities of 87%, 81%, and 75%; respective specificities of 93%, 90%, and 82%; negative predictive values of 45%, 64%, and 74%; and positive predictive values of 99%, 95%, and 83%. CONCLUSION: DUS is an optimal tool for quantification of SNS. However, a multisegment setting has a significant negative impact on the quantification of femoropopliteal artery stenosis.

Is There an Ideal Level of Platelet P2Y12-Receptor Inhibition in Patients Undergoing Percutaneous Coronary Intervention?: "Window" Analysis From the ADAPT-DES Study (Assessment of Dual AntiPlatelet Therapy With Drug-Eluting Stents).

OBJECTIVES: This study sought to determine whether there is an ideal level of platelet reactivity (PR) to optimize safety and efficacy within the large multicenter ADAPT-DES (Assessment of Dual AntiPlatelet Therapy With Drug-Eluting Stents) study of 8,582 patients receiving successful drug-eluting stent implantation. BACKGROUND: Patients with high PR on clopidogrel have a greater incidence of adverse ischemic events after stent implantation, whereas low PR may increase bleeding. Due to limited sample size, previous studies have not been able to adjust for differences in baseline characteristics that may confound the relationship of PR and outcomes. METHODS: In the ADAPT-DES study, routine platelet function testing (VerifyNow) was performed following clopidogrel loading. To characterize the independent association between PR and clinical events, patients were stratified into quintiles of P2Y12 reaction units (PRU). RESULTS: The PRU medians of the 5 quintiles were 57, 130, 187, 244, and 317 (most to least inhibited). There was a monotonic association between successively higher PRU quintiles and stent thrombosis, whereas for clinically relevant bleeding, the greatest risk occurred in the lowest PRU quintile, with similar risks across the 4 higher quintiles. These relationships remained significant in fully adjusted multivariable analyses (adjusted hazard ratio [HR] for stent thrombosis in Q5 versus Q1: 2.32; 95% confidence interval [CI]: 1.17 to 4.59; p = 0.02; adjusted HR for clinically relevant bleeding in Q5 versus Q1: 0.61; 95% CI: 0.47 to 0.77; p < 0.001). However, there were no significant independent associations between the level of PRU and mortality. CONCLUSIONS: In this large observational study, increasing PRU was associated with a monotonic increase in stent thrombosis, whereas bleeding risk was confined to the lowest PRU quintile, suggesting an optimal therapeutic window of platelet inhibition at moderately inhibited PRU. However, there was no demonstrable threshold effect for PRU and mortality in adjusted analyses, perhaps due to the offsetting impact of bleeding and ischemia across the spectrum of platelet inhibition. (Assessment of Dual AntiPlatelet Therapy With Drug-Eluting Stents [ADAPT-DES]; NCT00638794).

Relationship between intravascular ultrasound guidance and clinical outcomes after drug-eluting stents: the assessment of dual antiplatelet therapy with drug-eluting stents (ADAPT-DES) study.

BACKGROUND: Prior small to modest-sized studies suggest a benefit of intravascular ultrasound (IVUS) guidance in noncomplex lesions. Whether IVUS guidance is associated with improved clinical outcomes after drug-eluting stent (DES) implantation in an unrestricted patient population is unknown. METHODS AND RESULTS: Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents (ADAPT-DES) was a prospective, multicenter, nonrandomized "all-comers" study of 8583 consecutive patients at 11 international centers designed to determine the frequency, timing, and correlates of stent thrombosis and adverse clinical events after DES. Propensity-adjusted multivariable analysis was performed to examine the relationship between IVUS guidance and 1-year outcomes. IVUS was utilized in 3349 patients (39%), and larger-diameter devices, longer stents, and/or higher inflation pressures were used in 74% of IVUS-guided cases. IVUS guidance compared with angiography guidance was associated with reduced 1-year rates of definite/probable stent thrombosis (0.6% [18 events] versus 1.0% [53 events]; adjusted hazard radio, 0.40; 95% confidence interval, 0.21-0.73; P=0.003), myocardial infarction (2.5% versus 3.7%; adjusted hazard radio, 0.66; 95% confidence interval, 0.49-0.88; P=0.004), and composite adjudicated major adverse cardiac events (ie, cardiac death, myocardial infarction, or stent thrombosis) (3.1% versus 4.7%; adjusted hazard radio, 0.70; 95% confidence interval, 0.55-0.88; P=0.002). The benefits of IVUS were especially evident in patients with acute coronary syndromes and complex lesions, although significant reductions in major adverse cardiac events were present in all patient subgroups those with including stable angina and single-vessel disease. CONCLUSIONS: In ADAPT-DES, the largest study of IVUS use to date, IVUS guidance was associated with a reduction in stent thrombosis, myocardial infarction, and major adverse cardiac events within 1 year after DES implantation. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00638794.

A comprehensive approach to visual and functional assessment of experimental vascular lesions in vivo.

The rat carotid injury model is the most widely used model to study the pathophysiology of neointimal hyperplasia as well as the value of novel therapeutic approaches to limit vasoproliferative diseases such as restenosis. For lesion assessment, the current gold standard of histomorphometry neither provides integral insight into the vascular lesion in vivo nor assesses of functional lesion-associated flow alterations and the time course of lesion development. To overcome these limitations, we applied and validated duplex sonography as a novel tool for comprehensive lesions assessment in vivo. Left rat common carotid arteries (CCA) were balloon injured. Duplex sonography was performed in both injured and noninjured CCAs before and up to 14 days postinjury. Sham-operated animals served as controls. The parameters determined were vessel lumen diameter as well as systolic and end-diastolic flow velocity, time-dependent lesion development, and intra- and interobserver variability. Subsequently, the model was applied to validate the therapeutic effect of gene transfer into the vessel wall and compared with histomorphometry. We show that duplex sonography in the experimental carotid injury model allows accurate follow-up of lesion development in vivo with low intra- and interobserver variability. It can be easily adopted to assess the efficacy of therapeutic approaches even with limited technical experience and adds valuable functional data to mere postmortem histomorphometric analysis, thereby closing the gap between experimental approaches and clinical importance of vascular lesions.