Influence of Pathophysiological Patterns of Coronary Artery Disease on Immediate Percutaneous Coronary Intervention Outcomes.

BACKGROUND: Diffuse coronary artery disease (CAD) impacts the safety and efficacy of percutaneous coronary intervention (PCI). Pathophysiological CAD patterns can be quantified using fractional flow reserve (FFR) pullbacks incorporating the pullback pressure gradient (PPG) calculation. This study aimed to establish the capacity of PPG to predict optimal revascularisation and procedural outcomes. METHODS: This prospective, investigator-initiated, single-arm, multicentre study enrolled patients with at least one epicardial lesion with an FFR ≤ 0.80 scheduled for PCI. Manual FFR pullbacks were employed to calculate PPG. The primary outcome of optimal revascularisation was defined as a post-PCI FFR ≥ 0.88. RESULTS: 993 patients with 1044 vessels were included. The mean FFR was 0.68 ± 0.12, PPG 0.62 ± 0.17, and post-PCI FFR 0.87 ± 0.07. PPG was significantly correlated with the change in FFR after PCI (r=0.65, 95% CI 0.61-0.69, p<0.001) and demonstrated excellent predicted capacity for optimal revascularisation (AUC 0.82, 95% CI 0.79-0.84, p<0.001). Conversely, FFR alone did not predict revascularisation outcomes (AUC 0.54, 95% CI 0.50-0.57). PPG influenced treatment decisions in 14% of patients, redirecting them from PCI to alternative treatment modalities. Periprocedural myocardial infarction occurred more frequently in patients with low PPG (<0.62) compared to those with focal disease (OR 1.71, 95% CI: 1.00-2.97). CONCLUSIONS: Pathophysiological CAD patterns distinctly affect the safety and effectiveness of PCI. The PPG showed an excellent predictive capacity for optimal revascularisation and demonstrated added value compared to a FFR measurement.

Prevalence and anatomical factors associated with stent under-expansion in non-severely calcified lesions.

BACKGROUND: Stent underexpansion, typically related to lesion calcification, is the strongest predictor of adverse events after percutaneous coronary intervention (PCI). Although uncommon, underexpansion may also occur in non-severely calcified lesions. AIM: We sought to identify the prevalence and anatomical characteristics of underexpansion in non-severely calcified lesions. METHODS: We included 993 patients who underwent optical coherence tomography-guided PCI of 1051 de novo lesions with maximum calcium arc <180°. Negative remodeling (NR) was the smallest lesion site external elastic lamina diameter that was also smaller than the distal reference. Stent expansion was evaluated using a linear regression model accounting for vessel tapering; underexpansion required both stent expansion <70% and stent area <4.5mm2. RESULTS: Underexpansion was observed in 3.6% of non-heavily calcified lesions (38/1051). Pre-stent maximum calcium arc and thickness were greater in lesions with versus without underexpansion (median 119° vs. 85°, p = 0.002; median 0.95 mm vs. 0.78 mm, p = 0.008). NR was also more common in lesions with underexpansion (44.7% vs. 24.5%, p = 0.007). In the multivariable logistic regression model, larger and thicker eccentric calcium, mid left anterior descending artery (LAD) location, and NR were associated with underexpansion in non-severely calcified lesions. The rate of underexpansion was especially high (30.7%) in lesions exhibiting all three morphologies. Two-year TLF tended to be higher in underexpanded versus non-underexpanded stents (9.7% vs. 3.7%, unadjusted hazard ratio [95% confidence interval] = 3.02 [0.92, 9.58], p = 0.06). CONCLUSION: Although underexpansion in the absence of severe calcium (<180°) is uncommon, mid-LAD lesions with NR and large and thick eccentric calcium were associated with underexpansion.

Distinct Challenges of Eruptive and Non-Eruptive Calcified Nodules in Percutaneous Coronary Intervention.

PURPOSE OF REVIEW: To provide a summary of prevalence, pathogenesis, and treatment of coronary calcified nodules (CNs). RECENT FINDINGS: CNs are most frequently detected at the sites of hinge motion of severely calcified lesions such as in the middle segment of right coronary artery and left main coronary bifurcation. On histopathology, CNs exhibit two distinctive morphologies: eruptive and non-eruptive. Eruptive CNs, which have a disrupted fibrous cap with adherent thrombi, are biologically active. Non-eruptive CNs, which have an intact fibrous cap without thrombi, are biologically inactive, representing either healed eruptive CNs or protrusion of calcium due to plaque progression. Recent studies using optical coherence tomography (OCT) have shown a difference in the mechanism of stent failure in the two subtypes, demonstrating early reappearance of eruptive CNs in the stent (at ~ 6 months) as a unique mechanism of stent failure that does not seem to be preventable by simply achieving adequate stent expansion. The cause of CN reappearance in stent is not known and could be due to acute or subacute intrusion or continued growth of the CN. Whether modification of CN is needed, the most effective calcium modification modality and effectiveness of stent implantation in eruptive CNs has not been elucidated. In this review, we discuss pathogenesis of CNs and how intravascular imaging can help diagnose and manage patients with CNs. We also discuss medical and transcatheter therapies beyond conventional stent implantation for effective treatment of eruptive CNs that warrant testing in prospective studies.

Utility of optical coherence tomography in acute coronary syndromes.

Studies utilizing intravascular imaging have replicated the findings of histopathological studies, identifying the most common substrates for acute coronary syndromes (ACS) as plaque rupture, erosion, and calcified nodule, with spontaneous coronary artery dissection, coronary artery spasm, and coronary embolism constituting the less common etiologies. The purpose of this review is to summarize the data from clinical studies that have used high-resolution intravascular optical coherence tomography (OCT) to assess culprit plaque morphology in ACS. In addition, we discuss the utility of intravascular OCT for effective treatment of patients presenting with ACS, including the possibility of culprit lesion-based treatment by percutaneous coronary intervention.

Optical coherence tomography versus angiography and intravascular ultrasound to guide coronary stent implantation: A systematic review and meta-analysis.

BACKGROUND: Optical coherence tomography (OCT) is an adjunct to angiography-guided coronary stent placement. However, in the absence of dedicated, appropriately powered randomized controlled trials, the impact of OCT on clinical outcomes is unclear. OBJECTIVE: To conduct a systematic review and meta-analysis of all available studies comparing OCT-guided versus angiography-guided and intravascular ultrasound (IVUS)-guided coronary stent implantation. METHODS: MEDLINE and Cochrane Central were queried from their inception through July 2022 for all studies that sought to compare OCT-guided percutaneous coronary intervention (PCI) to angiography-guided and IVUS-guided PCI. The primary endpoint was minimal stent area (MSA) compared between modalities. Clinical endpoints of interest were all-cause and cardiovascular mortality, major adverse cardiovascular events (MACE), myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), and stent thrombosis (ST). Risk ratios (RRs) and mean differences (MDs) with their corresponding 95% confidence intervals (CIs) were pooled using a random-effects model. RESULTS: Thirteen studies (8 randomized control trials and 5 observational studies) enrolling 6312 participants were included. OCT was associated with a strong trend toward increased MSA compared to angiography (MD = 0.36, p = 0.06). OCT-guided PCI was also associated with a reduction in the incidence of all-cause mortality [RR = 0.59, 95% CI (0.35, 0.97), p = 0.04] and cardiovascular mortality [RR = 0.41, 95% CI (0.21, 0.80), p = 0.009] compared with angiography-guided PCI. Point estimates favored OCT relative to angiography in MACE [RR = 0.75, 95% CI (0.47, 1.20), p = 0.22] and MI [RR = 0.75, 95% CI (0.53, 1.07), p = 0.12]. No differences were detected in ST [RR = 0.71, 95% CI (0.21, 2.44), p = 0.58], TLR [RR = 0.71, 95% CI (0.17, 3.05), p = 0.65], or TVR rates [RR = 0.89, 95% CI (0.46, 1.73), p = 0.73]. Compared with IVUS guidance, OCT guidance was associated with a nonsignificant reduction in the MSA (MD = -0.16, p = 0.27). The rates of all-cause and cardiovascular mortality, MACE, MI, TLR, TVR, or ST were similar between OCT-guided and IVUS-guided PCI. CONCLUSIONS: OCT-guided PCI was associated with reduced all-cause and cardiovascular mortality compared to angiography-guided PCI. These results should be considered hypothesis generating as the mechanisms for the improved outcomes were unclear as no differences were detected in the rates of TLR, TVR, or ST. OCT- and IVUS-guided PCI resulted in similar post-PCI outcomes.

Multicenter clinical evaluation of a piezoresistive-MEMS-sensor rapid-exchange pressure microcatheter system for fractional flow reserve measurement.

OBJECTIVES: This multicenter, prospective clinical study investigates whether the microelectromechanical-systems-(MEMS)-sensor pressure microcatheter (MEMS-PMC) is comparable to a conventional pressure wire in fractional flow reserve (FFR) measurement. BACKGROUND: As a conventional tool for FFR measurement, pressure wires (PWs) still have some limitations such as suboptimal handling characteristics and unable to maintain the wire position during pullback assessment. Recently, a MEMS-PMC compatible with any 0.014″ guidewire is developed. Compared with the existing optical-sensor PMC, this MEMS-PMC has smaller profiles at both the lesion crossing and sensor packaging areas. METHODS: Two hundred and forty-two patients with visually 30-70% coronary stenosis were enrolled at four centers. FFR was measured first with the MEMS-PMC, and then with the PW. The primary endpoint was the Bland-Altman mean bias between the MEMS-PMC and PW FFR. RESULTS: From the 224-patient per-protocol data, quantitative coronary angiography showed 17.9% and 55.9% vessels had diameter < 2.5 mm and stenosis >50%, respectively. The two systems' mean bias was -0.01 with [-0.08, 0.06] 95% limits-of-agreement. Using PW FFR≤0.80 as cutoff, the MEMS-PMC per-vessel diagnostic accuracy was 93.4% [95% confidence interval: 89.4-96.3%]. The MEMS-PMC's success rate was similar to that of PW (97.5 vs. 96.3%, p = .43) with no serious adverse event, and its clinically-significant (>0.03) drift rate was 43% less (9.5 vs. 16.7%, p = .014). CONCLUSIONS: Our study showed the MEMS-PMC is safe to use and has a minimal bias equal to the resolution of current FFR systems. Given the MEMS-PMC's high measurement accuracy and rapid-exchange nature, it may become an attractive new tool facilitating routine coronary physiology assessment.

Left coronary artery calcification patterns after coronary bypass graft surgery: An in-vivo optical coherence tomography study.

OBJECTIVES: We sought to evaluate the severity and patterns of calcifications in the left main coronary artery (LMCA) and proximal segments of left anterior descending coronary artery (LAD) and left circumflex artery (LCX) using optical coherence tomography (OCT) in patients with and without prior coronary artery bypass grafting (CABG). BACKGROUND: CABG may accelerate upstream calcium development. METHODS: OCT images (n = 76) of the LMCA bifurcation from either the LAD or LCX in 76 patients with at least one patent left coronary graft, on average 7.0 ± 5.6 years post-CABG, were compared with 148 OCT images in propensity-score-matched non-CABG controls. RESULTS: Minimum lumen areas in the LMCA, LAD, and LCX in post-CABG patients were smaller than non-CABG controls. Maximum calcium arc and thickness as well as calcium length were greater in the LMCA and LCX, but not in the LAD in post-CABG patients versus non-CABG controls. Calcium located at the carina of a bifurcation, calcified nodules (CN), thin intimal calcium, and lobulated calcium were more prevalent in post-CABG patients. After adjusting for multiple covariates, prior CABG was an independent predictor of calcification at the carina of a bifurcation (odds ratio [OR] 5.77 [95% confidence interval, CI: 1.5-21.6]), thin intimal calcium (4.7 [1.5-14.4]), and the presence of a CN (15.60 [3.2-76.2]). CONCLUSIONS: Prior CABG is associated with greater amount of calcium in the LMCA and the proximal LCX, as well as higher prevalence of atypical calcium patterns, including CN, thin or lobulated calcium, and calcifications located at the carina of a bifurcation, compared with non-CABG controls.

Therapeutic Approach to Calcified Coronary Lesions: Disruptive Technologies.

PURPOSE OF REVIEW: Moderate or severe calcification is present in approximately one third of coronary lesions in patients with stable ischemic heart disease and acute coronary syndromes and portends unfavorable procedural results and long-term outcomes. In this review, we provide an overview on the state-of-the-art in evaluation and treatment of calcified coronary lesions. RECENT FINDINGS: Intravascular imaging (intravascular ultrasound or optical coherence tomography) can guide percutaneous coronary intervention of severely calcified lesions. New technologies such as orbital atherectomy and intravascular lithotripsy have significantly expanded the range of available techniques to effectively modify coronary calcium and facilitate stent expansion. Calcium fracture improves lesion compliance and is essential to optimize stent implantation. Intravascular imaging allows for detailed assessment of patterns and severity of coronary calcium that are integrated into scoring systems to predict stent expansion, identifying which lesions require atherectomy for lesion modification. Guided by intravascular imaging, older technologies such as rotational atherectomy and excimer laser can be incorporated with newer technologies such as orbital atherectomy and intravascular lithotripsy into an algorithmic approach for the safe and effective treatment of patients with heavily calcified coronary lesions.

Accuracy of Fractional Flow Reserve Derived From Coronary Angiography.

BACKGROUND: Measuring fractional flow reserve (FFR) with a pressure wire remains underutilized because of the invasiveness of guide wire placement or the need for a hyperemic stimulus. FFR derived from routine coronary angiography (FFRangio) eliminates both of these requirements and displays FFR values of the entire coronary tree. The FFRangio Accuracy versus Standard FFR (FAST-FFR) study is a prospective, multicenter, international trial with the primary goal of determining the accuracy of FFRangio. METHODS: Coronary angiography was performed in a routine fashion in patients with suspected coronary artery disease. FFR was measured in vessels with coronary lesions of varying severity using a coronary pressure wire and hyperemic stimulus. Based on angiograms of the respective arteries acquired in ≥2 different projections, on-site operators blinded to FFR then calculated FFRangio using proprietary software. Coprimary end points were the sensitivity and specificity of the dichotomously scored FFRangio for predicting pressure wire-derived FFR using a cutoff value of 0.80. The study was powered to meet prespecified performance goals for sensitivity and specificity. RESULTS: Ten centers in the United States, Europe, and Israel enrolled a total of 301 subjects and 319 vessels meeting inclusion/exclusion criteria which were included in the final analysis. The mean FFR was 0.81 and 43% of vessels had an FFR≤0.80. The per-vessel sensitivity and specificity were 94% (95% CI, 88% to 97%) and 91% (86% to 95%), respectively, both of which exceeded the prespecified performance goals. The diagnostic accuracy of FFRangio was 92% overall and remained high when only considering FFR values between 0.75 to 0.85 (87%). FFRangio values correlated well with FFR measurements ( r=0.80, P<0.001) and the Bland-Altman 95% confidence limits were between -0.14 and 0.12. The device success rate for FFRangio was 99%. CONCLUSIONS: FFRangio measured from the coronary angiogram alone has a high sensitivity, specificity, and accuracy compared with pressure wire-derived FFR. FFRangio has the promise to substantially increase physiological coronary lesion assessment in the catheterization laboratory, thereby potentially leading to improved patient outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique Identifier: NCT03226262.

Real world validation of the nonhyperemic index of coronary artery stenosis severity-Resting full-cycle ratio-RE-VALIDATE.

OBJECTIVE: The primary objective was to demonstrate diagnostic equivalence between RFR and iFR in clinical practice. BACKGROUND: The instantaneous wave-free ratio (iFR), a nonhyperemic pressure ratio (NHPR), has been shown to be noninferior to fractional flow reserve (FFR) in determining coronary artery stenosis severity in intermediate lesions. However, iFR has a number of inherent limitations, including sensitive landmarking of the pressure waveform and the assumption that maximal flow and minimal microcirculatory resistance occur during a fixed period within diastole. The resting full-cycle ratio (RFR) is a novel NHPR which evaluates the entire cardiac cycle independent of the ECG, landmark identification, and timing within the cardiac cycle. METHODS: RE-VALIDATE RFR was designed to determine the diagnostic utility of RFR for the physiological assessment of coronary artery disease in clinical practice compared to iFR. RFR was also tested for equivalence (1% margin), diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), areas under the receiver operated characteristic curve (AUC), and correlations compared to calculated iFR (iFRcalc ). RESULTS: From two centers, 501 blinded rest- and hyperemic pressure recordings from 431 patients were suitable for analysis according to a core laboratory. The mean FFR, RFR, and iFRcalc were 0.80 ± 0.09, 0.90 ± 0.08, and 0.90 ± 0.08, respectively. Based on a binary cut-off approach (RFR/iFR ≤0.89), RFR demonstrated equivalence with iFRcalc (95% confidence interval: 0.025-0.019) with overall diagnostic accuracy 97.8%, sensitivity 97.8%, specificity 97.8%, PPV 96.2%, NPV 98.7%, and AUC 0.96 (0.94-0.97, p < .001). RFR had a mean bias 0.003 (95% limits of agreement: 0.019, -0.025). CONCLUSIONS: RFR was equivalent to iFR in clinical practice. RFR is an alternative NHPR, avoiding the need for hyperemic agents, thus potentially reducing side effects, procedural time and cost compared to FFR.

Hot topics in interventional cardiology: Proceedings from the society for cardiovascular angiography and interventions 2020 think tank.

The society for cardiovascular angiography and interventions (SCAI) think tank is a collaborative venture that brings together interventional cardiologists, administrative partners, and select members of the cardiovascular industry community for high-level field-wide discussions. The 2020 think tank was organized into four parallel sessions reflective of the field of interventional cardiology: (a) coronary intervention, (b) endovascular medicine, (c) structural heart disease, and (d) congenital heart disease (CHD). Each session was moderated by a senior content expert and co-moderated by a member of SCAI's emerging leader mentorship program. This document presents the proceedings to the wider cardiovascular community in order to enhance participation in this discussion, create additional dialogue from a broader base, and thereby aid SCAI and the industry community in developing specific action items to move these areas forward.

Effect of orbital atherectomy in calcified coronary artery lesions as assessed by optical coherence tomography.

OBJECTIVES: We sought to assess plaque modification and stent expansion following orbital atherectomy (OA) for calcified lesions using optical coherence tomography (OCT). BACKGROUND: The efficacy of OA for treating calcified lesions is not well studied, especially using intravascular imaging in vivo. METHODS: OCT was performed preprocedure, post-OA, and post-stent (n = 58). Calcium modification after OA was defined as a round, concave, polished calcium surface. Calcium fracture was complete discontinuity of calcium. RESULTS: Comparing pre- vs post-OA OCT (n = 29), calcium area was significantly decreased post-OA (from 3.4 mm2 [2.4-4.7] to 2.9 mm2 [1.9-3.9], P < 0.001). Poststent percent calcium fracture (calcium fracture length/calcium length) correlated with post-OA percent calcium modification (calcium modification length/calcium length) (r = 0.31, P = 0.01). Among 75 calcium fractures in 35 lesions, maximum calcium thickness at the fracture site was greater with vs without calcium modification (0.58 mm [0.50-0.66] vs 0.45 mm [0.38-0.52], P = 0.003). Final optimal stent expansion, defined as minimum stent area ≥6.1 mm2 or stent expansion ≥90% (medians of this cohort) at the maximum calcium angle site, was observed in 41 lesions. Larger post-OA lumen area (odds ratio 2.64; 95% CI 1.21-5.76; P = 0.02) and the presence of calcium fracture (odds ratio 6.77; 95% CI 1.25-36.6; P = 0.03) were independent predictors for optimal stent expansion. CONCLUSIONS: Calcium modification by OA facilitates poststent calcium fracture even in thick calcium. Greater calcium modification correlated with greater calcium fracture, in turn resulting in better stent expansion.

Predictive factors of discordance between the instantaneous wave-free ratio and fractional flow reserve.

OBJECTIVES: To identify clinical, angiographic and hemodynamic predictors of discordance between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR). BACKGROUND: The iFR was found to be non-inferior to the gold-standard FFR for guiding coronary revascularization, although it is discordant with FFR in 20% of cases. A better understanding of the causes of discordance may enhance application of these indices. METHODS: Both FFR and iFR were measured in the prospective multicenter CONTRAST study. Clinical, angiographic and hemodynamic variables were compared between patients with concordant values of FFR and iFR (cutoff ≤0.80 and ≤0.89, respectively). RESULTS: Out of the 587 patients included, in 466 patients (79.4%) FFR and iFR agreed: both negative, n = 244 (41.6%), or positive, n = 222 (37.8%). Compared with FFR, iFR was negative discordant (FFR+/iFR-) in 69 (11.8%) patients and positive discordant (FFR-/iFR+) in 52 (8.9%) patients. On multivariate regression, stenosis location (left main or proximal left anterior descending) (OR: 3.30[1.68;6.47]), more severe stenosis (OR: 1.77[1.35;2.30]), younger age (OR: 0.93[0.90;0.97]), and slower heart rate (OR: 0.59[0.42;0.75]) were predictors of a negative discordant iFR. Absence of a beta-blocker (OR: 0.41[0.22;0.78]), older age (OR: 1.04[1.00;1.07]), and less severe stenosis (OR: 0.69[0.53;0.89]) were predictors of a positive discordant iFR. CONCLUSIONS: During iFR acquisition, stenosis location, stenosis degree, heart rate, age and use of beta blockers influence concordance with FFR and should be taken into account when interpreting iFR.

Utility of intracoronary imaging in the cardiac catheterization laboratory: comprehensive evaluation with intravascular ultrasound and optical coherence tomography.

Background: Intracoronary imaging is an important tool for guiding decision making in the cardiac catheterization laboratory. Sources of data: We have reviewed the latest available evidence in the field to highlight the various potential benefits of intravascular imaging. Areas of agreement: Coronary angiography has been considered the gold standard test to appropriately diagnose and manage patients with coronary artery disease, but it has the inherent limitation of being a 2-dimensional x-ray lumenogram of a complex 3-dimensional vascular structure. Areas of controversy: There is well-established inter- and intra-observer variability in reporting coronary angiograms leading to potential variability in various management strategies. Intracoronary imaging improves the diagnostic accuracy while optimizing the results of an intervention. Utilization of intracoronary imaging modalities in routine practice however remains low worldwide. Increased costs, resources, time and expertise have been cited as explanations for low incorporation of these techniques. Growing points: Intracoronary imaging supplements and enhances an operator's decision-making ability based on detailed and objective lesion assessment rather than a subjective visual estimation. The benefits of intravascular imaging are becoming more profound as the complexity of cases suitable for revascularization increases. Areas timely for developing research: While the clinical benefits of intravascular ultrasound have been well validated, optical coherence tomography in comparison is a newer technology, with robust clinical trials assessing its clinical benefit are underway.

Precision percutaneous coronary intervention: Is optical coherence tomography co-registration the future?

Integration of angiographic co-registration (ACR) with optical coherence tomography (OCT) leads to significant changes in PCI strategy. ACR with OCT allows complete integration of all available data-points to aid decision making. Randomized clinical trials comprehensively evaluating the impact of OCT with ACR to improve clinical outcomes are ongoing.

The impact of unfractionated heparin or bivalirudin on patients with stable coronary artery disease undergoing percutaneous coronary intervention.

OBJECTIVES: To compare bleeding and clinical events of patients with stable angina or silent ischemia undergoing percutaneous coronary intervention (PCI) treated with unfractionated heparin (UFH) or bivalirudin. BACKGROUND: Few direct comparisons between UFH monotherapy versus bivalirudin exist for patients with stable ischemic heart disease undergoing PCI. METHODS: A prospective, investigator-initiated, single-center, single-blinded, randomized trial of UFH versus bivalirudin was conducted. The primary endpoint was all bleeding (major and minor) from index-hospitalization to 30 days post discharge. Secondary endpoints included major adverse cerebral and cardiovascular events (MACCE) and net adverse clinical events (NACE). RESULTS: Two-hundred-sixty patients were randomized for treatment with either UFH (n = 123) (47%) or bivalirudin (n = 137) (53%) There were no significant differences in baseline clinical and angiographic characteristics between the two groups. Primary endpoint was similar in both groups (10.9% with bivalirudin vs 7.3% with UFH [P = 0.31]). Major bleeding rates were 5.8% and 2.4%, respectively (P = 0.17). There was a higher MACCE (3.5% vs 0%, P = 0.03) and NACE (8.8% vs 2.4%, P = 0.03) rate with bivalirudin compared to UFH, respectively. Bivalirudin had increased odds of NACE (OR = 3.65, 95% CI: 1.00-13.3.6). Death and stent thrombosis rates were low and similar in both groups. Radial access was associated with fewer bleeding events compared to femoral access but not statistically significant (P = 0.29). CONCLUSIONS: Among patients with stable angina or silent ischemia, there was no difference between UFH and bivalirudin in bleeding rates up to 30-days post-PCI. MACCE and NACE were higher among the bivalirudin group. Radial access was associated with a numerically lower rate of bleeding compared with femoral access.

Diabetes does not impact the diagnostic performance of contrast-based fractional flow reserve: insights from the CONTRAST study.

BACKGROUND: Adenosine-free coronary pressure wire metrics have been proposed to test the functional significance of coronary artery lesions, but it is unexplored whether their diagnostic performance might be altered in patients with diabetes. METHODS: We performed a post-hoc analysis of the CONTRAST study, which prospectively enrolled an international cohort of patients undergoing routine fractional flow reserve (FFR) assessment for standard indications. Paired, repeated measurements of all physiology metrics (Pd/Pa, iFR, contrast-based FFR, and FFR) were made. A central core laboratory analyzed blinded pressure tracings in a standardized fashion. RESULTS: Of 763 subjects enrolled at 12 international centers, 219 (29%) had diabetes. The two groups were well-balanced for age, clinical presentation (stable or unstable), coronary vessel studied, volume and type of intracoronary contrast, and volume of intracoronary adenosine. A binary threshold of cFFR ≤ 0.83 produced an accuracy superior to both Pd/Pa and iFR when compared with FFR ≤ 0.80 in the absence of significant interaction with diabetes status; indeed, accuracy in subgroups of patients with or without diabetes was similar for cFFR (86.7 vs 85.4% respectively; p = 0.76), iFR (84.2 vs 80.0%, p = 0.29) and Pd/Pa (81.3 vs 78.9%, p = 0.55). There was no significant heterogeneity between patients with or without diabetes in terms of sensitivity and specificity of all metrics. The area under the receiver operating characteristic (ROC) curve was largest for cFFR compared with Pd/Pa and iFR which were equivalent (cFFR 0.961 and 0.928; Pd/Pa 0.916 and 0.870; iFR 0.911 and 0.861 in diabetic and non-diabetic patients respectively). CONCLUSIONS: cFFR provides superior diagnostic performance compared with Pd/Pa or iFR for predicting FFR irrespective of diabetes (clinicaltrials.gov identifier NCT02184117).

Coronary resting gradients for hemodynamic lesion assessment - The future of coronary physiology?

Coronary resting gradient measurements with cut-off values of ≤0.87 and ≥0.93 portend a high degree of certainty with respect to appropriateness of coronary revascularization Less agreement exists in patients in the so called indeterminate "gray zone" Pressure-bounded coronary flow reserve may aid in our understanding of the underlying physiologic principles and facilitate the clinical assessment of these lesions.

Long-term outcomes following fractional flow reserve-guided treatment of angiographically ambiguous left main coronary artery disease: A meta-analysis of prospective cohort studies.

OBJECTIVE: To define the long term outcomes of Fractional Flow Reserve (FFR) guided revascularization of ambiguous left main coronary artery (LMCA) lesions by performing a pooled meta-analysis of all available studies. BACKGROUND: Prospective studies evaluating the use of fractional flow reserve (FFR) for clinical decision-making in ambiguous unprotected left main coronary artery (LMCA) stenosis suggest the relative safety of that approach, but any final conclusions are limited by small sample size. We performed a pooled meta-analysis of studies to define the long-term outcomes in these patients. METHODS: Six prospective cohort studies involving 525 patients met the inclusion criteria. Patients underwent revascularization (revascularization group) or medical therapy (deferred group) based on FFR. The primary outcome was defined as rate of major cardiovascular events (a composite of death from all causes, nonfatal myocardial infarctions and subsequent revascularizations). The secondary outcomes included individual components of the primary end point. Pooled effect sizes were calculated using a fixed effects model. RESULTS: Based on the FFR results, 217 patients (41%) underwent revascularization. There was no statistically significant difference between the groups in the rates of primary end point (P = 0.15), all-cause mortality (P = 0.06) or nonfatal myocardial infarctions (P = 0.76). However, there was a significant increase in the rate of subsequent revascularizations in the deferred patients (P = 0.002). CONCLUSION: The long term clinical outcomes in patients with ambiguous LMCA stenosis for whom revascularization is deferred based on FFR are favorable and similar to the revascularized group in terms of overall mortality and subsequent myocardial infarctions.

Impact of glomerular filtration rate on clinical outcomes after carotid artery revascularization in 11,832 patients from the CARE registry.

OBJECTIVE: The aim of this study was to assess the association of kidney function with carotid artery revascularization outcomes in a large contemporary database. BACKGROUND: Chronic kidney disease (CKD) is associated with increased mortality and adverse cardiovascular events after coronary intervention. There are limited data evaluating the association between CKD and adverse events among patients undergoing carotid artery revascularization procedures. METHODS: The Carotid Artery Revascularization and Endarterectomy (CARE) Registry is a voluntary registry of 168 hospitals. Using data from the CARE Registry, we examined registry patients undergoing carotid artery revascularization by either carotid endarterectomy (CEA) or carotid artery stenting (CAS) from May 2005 through March 2010. Patients were divided into four groups according to their glomerular filtration rate (GFR), as estimated by the Modification of Diet in Renal Disease Study Group equation using preprocedural serum creatinine levels. RESULTS: The analysis included 11,832 patients who underwent carotid revascularization (6,899 CAS and 4,933 CEA). Patients with lower GFR were older, more frequently female, had more comorbidities, including hypertension, dyslipidemia, peripheral arterial disease, diabetes mellitus, chronic lung disease, ischemic heart disease, heart failure, and reduced left ventricular function, and were more likely to undergo CAS than CEA. In the overall population, CKD was associated with higher unadjusted in-hospital and 30-day rates of the combined endpoint of death, stroke, and myocardial infarction and the individual endpoint of stroke. After adjustment for baseline and preprocedural characteristics, CKD was not an independent predictor of adverse events in either CAS or CEA. CONCLUSIONS: Patients with CKD have a greater number of comorbidities and worse unadjusted in-hospital and 30-day outcomes; CKD was not, however, an independent predictor of in-hospital and 30-day outcomes after carotid artery revascularization.