Optical Coherence Tomography-Based Functional Stenosis Assessment: FUSION-A Prospective Multicenter Trial.

BACKGROUND: Intravascular imaging and intracoronary physiology may both be used to guide and optimize percutaneous coronary intervention; however, they are rarely used together. The virtual flow reserve (VFR) is an optical coherence tomography (OCT)-based model of fractional flow reserve (FFR) facilitating the assessment of the physiological significance of coronary lesions. We aimed to validate the VFR assessment of intermediate coronary artery stenoses. METHODS: FUSION (Validation of OCT-Based Functional Diagnosis of Coronary Stenosis) was a multicenter, prospective, observational study comparing OCT-derived VFR to invasive FFR. VFR was mathematically derived from a lumped parameter flow model based on 3-dimensional lumen morphology. Patients undergoing coronary angiography with intermediate angiographic stenosis (40%-90%) requiring physiological assessment were enrolled. Investigational sites were blinded to the VFR analysis, and all OCT and FFR data were reviewed by an independent core laboratory. The coprimary end points were the sensitivity and specificity of VFR against FFR as the reference standard, each of which was tested against prespecified performance goals. RESULTS: After core laboratory review, 266 vessels in 224 patients from 25 US centers were included in the analysis. The mean angiographic diameter stenosis was 65.5%±14.9%, and the mean FFR was 0.83±0.11. Overall accuracy, sensitivity, and specificity of VFR versus FFR using a binary cutoff point of 0.80 were 82.0%, 80.4%, and 82.9%, respectively. The 97.5% lower confidence bound met the prespecified performance goal for sensitivity (71.6% versus 70%; P=0.01) and specificity (76.6% versus 75%; P=0.01). The area under the curve was 0.88 (95% CI, 0.84-0.92; P<0.0001). CONCLUSIONS: OCT-derived VFR demonstrates high sensitivity and specificity for predicting invasive FFR. Integrating high-resolution intravascular imaging with imaging-derived physiology may provide synergistic benefits as an adjunct to percutaneous coronary intervention. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT04356027.

Optical Coherence Tomography Assessment of Morphological Characteristics in Suspected Coronary Artery Disease, but Angiographically Nonobstructive Lesions.

BACKGROUND/PURPOSE: We sought to evaluate the morphological characteristics of nonobstructive coronary lesions in patients with ischemic symptoms and/or signs. MATERIALS/METHODS: We used optical coherence tomography (OCT) to assess the presumed culprit lesion in 142 patients with suspected coronary artery disease in whom coronary angiography showed no lesion with a diameter stenosis ≥50%. Patients with a clinical diagnosis of acute coronary syndrome (ACS, n = 31, including 2 ST-elevation myocardial infarction, 9 non-ST-elevation myocardial infarction, and 20 unstable angina pectoris) were compared to those with stable coronary artery disease (CAD) (n = 111) including 79 patients with stable angina and 32 patients with silent ischemia (positive non-invasive stress test only). RESULTS: The overall prevalence of thrombus, plaque rupture, intimal laceration, or calcified nodule in the combined groups was 23.2% (33/142) including 15 thrombus, 12 plaque rupture, 9 calcified nodule, and 8 intimal laceration (not mutually exclusive) without differences between ACS and stable CAD patients. Also the prevalence of thin-cap fibroatheroma was not significantly different between ACS and stable patients (12.9% vs 6.3%, p = 0.22). Minimum lumen area (3.1 mm2 [2.3, 4.1] versus 3.2 mm2 [2.4, 4.7], p = 0.7) and area stenosis (49.9% [37.1, 56.4] versus 48.1% [37.8, 55.8], p = 0.9) were similar between ACS and stable CAD patients. CONCLUSION: In patients presenting with ischemic symptoms and/or signs, but angiographically nonobstructive culprit lesions, approximately 25% had abnormal findings by OCT-whether patients presented with acute/unstable or stable CAD.

Impact of an integrated treatment algorithm based on platelet function testing and clinical risk assessment: results of the TRIAGE Patients Undergoing Percutaneous Coronary Interventions To Improve Clinical Outcomes Through Optimal Platelet Inhibition study.

Assessment of platelet reactivity alone for thienopyridine selection with percutaneous coronary intervention (PCI) has not been associated with improved outcomes. In TRIAGE, a prospective multicenter observational pilot study we sought to evaluate the benefit of an integrated algorithm combining clinical risk and platelet function testing to select type of thienopyridine in patients undergoing PCI. Patients on chronic clopidogrel therapy underwent platelet function testing prior to PCI using the VerifyNow assay to determine high on treatment platelet reactivity (HTPR, ≥230 P2Y12 reactivity units or PRU). Based on both PRU and clinical (ischemic and bleeding) risks, patients were switched to prasugrel or continued on clopidogrel per the study algorithm. The primary endpoints were (i) 1-year major adverse cardiovascular events (MACE) composite of death, non-fatal myocardial infarction, or definite or probable stent thrombosis; and (ii) major bleeding, Bleeding Academic Research Consortium type 2, 3 or 5. Out of 318 clopidogrel treated patients with a mean age of 65.9 ± 9.8 years, HTPR was noted in 33.3 %. Ninety (28.0 %) patients overall were switched to prasugrel and 228 (72.0 %) continued clopidogrel. The prasugrel group had fewer smokers and more patients with heart failure. At 1-year MACE occurred in 4.4 % of majority HTPR patients on prasugrel versus 3.5 % of primarily non-HTPR patients on clopidogrel (p = 0.7). Major bleeding (5.6 vs 7.9 %, p = 0.47) was numerically higher with clopidogrel compared with prasugrel. Use of the study clinical risk algorithm for choice and intensity of thienopyridine prescription following PCI resulted in similar ischemic outcomes in HTPR patients receiving prasugrel and primarily non-HTPR patients on clopidogrel without an untoward increase in bleeding with prasugrel. However, the study was prematurely terminated and these findings are therefore hypothesis generating.

Determinants of bare-metal stent use in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention.

Bare-metal stent (BMS) use in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has been associated with higher rates of adverse cardiac events, including target lesion and target vessel revascularization. The purpose of the present study was to determine which clinical characteristics predict BMS use in patients with STEMI undergoing primary PCI. Data were prospectively collected from all patients who underwent primary PCI for STEMI between January 1, 2004 and December 31, 2007 at four New York State academic medical centers. Demographics, baseline medical history, procedural characteristics, and in-hospital outcomes were compared in patients receiving DESs versus BMSs. Of the 1394 patients studied, a total of 290 (20.8%) patients received a BMS while 1104 (79.2%) received a DES. Patients receiving a BMS were more likely to have higher rates of prior coronary artery bypass graft surgery, prior PCI, peripheral vascular disease, and diabetes mellitus, and were more likely to be Hispanic and uninsured. They were also more likely to present with stent thrombosis and worse left ventricular ejection fraction (LVEF). Patients receiving a BMS had significantly longer hospital length of stay and a trend toward higher all-cause in-hospital mortality. In multivariate analysis, independent predictors of BMS use included uninsured status (versus private insurance) (odds ratio [OR], 2.81; 95% confidence interval [CI], 1.70-4.67), peripheral vascular disease (OR, 1.96; 95% CI, 1.08- 3.56), and LVEF (OR, 0.98; 95% CI, 0.97-0.99). In conclusion, in this analysis of a contemporary cohort of patients undergoing primary PCI, lack of health insurance, peripheral vascular disease, and worse LVEF were independently associated with higher rates of BMS implantation in patients with STEMI undergoing primary PCI.

Association of health insurance status with presentation and outcomes of coronary artery disease among nonelderly adults undergoing percutaneous coronary intervention.

OBJECTIVE: The aim of this study was to determine if insurance status is associated with adverse outcomes in patients with coronary artery disease. METHODS: A cohort of 13,456 patients who underwent percutaneous coronary intervention (PCI) between January 1, 2004, and December 31, 2007, at 4 New York State teaching hospitals was retrospectively studied. The primary outcome of interest was in-hospital mortality from any cause. RESULTS: Of the 13,456 patients studied, 11,927 (88.6%) were insured by private carriers, 1,036 (7.7%) patients were covered by Medicaid, and 493 (3.7%) were uninsured. Uninsured and Medicaid patients tended to be younger and more often nonwhite and Hispanic. They had a higher prevalence of congestive heart failure and worse left ventricular function. Compared with privately insured patients, uninsured and Medicaid patients had increased all-cause mortality (1.2% and 0.9%, respectively, vs 0.3%; P < .001). For all patients, lack of insurance (OR 3.02, 95% CI 1.10-8.28) and Medicaid (OR 4.39, 95% CI 1.93-9.99) were independently associated with mortality. Lack of insurance (OR 5.02, 95% CI 1.58-15.93) and Medicaid (OR 4.55, 95% CI 1.19-17.45) were also independently associated with increased mortality in patients undergoing emergent PCI. CONCLUSION: Lack of insurance and Medicaid insurance are both independently associated with an increased risk of in-hospital mortality after PCI for coronary artery disease.