Clinical Utility of a Precision Medicine Test Evaluating Outpatients with Suspected Obstructive Coronary Artery Disease.

BACKGROUND: Identifying patients with obstructive coronary artery disease can be challenging for primary care physicians. Advances in precision medicine may help augment clinical tools and redefine the paradigm for evaluating coronary artery disease in the outpatient setting. A blood-based age/sex/gene expression score (ASGES) incorporating key features of precision medicine has shown clinical validity with a 96% negative predictive value and 89% sensitivity in estimating a symptomatic patient's current likelihood of obstructive coronary artery disease. To better characterize the clinical utility of the ASGES and measure its impact on clinician decision-making, a community-based registry was established. METHODS: The prospective PRESET Registry (NCT01677156) enrolled stable, nonacute adult patients presenting with typical or atypical symptoms suggestive of obstructive coronary artery disease from 21 US primary care practices from August 2012 to August 2014. Demographics, clinical characteristics, and ASGES results (predefined as low [ASGES ≤15] or elevated [ASGES >15]) were collected, as were referrals to Cardiology or further functional/anatomic cardiac testing after ASGES testing. Patients were followed for 1 year post ASGES testing. RESULTS: Among the 566-patient cohort (median age 56 years), clinicians referred 26/252 (10%) of patients with low scores vs 137/314 (44%) of patients with elevated scores to Cardiology or advanced cardiac testing for further evaluation (unadjusted odds ratio 0.15, P <.0001; adjusted odds ratio after accounting for clinical covariates = 0.18, P <.0001). Data on 84 patients referred for advanced cardiac testing showed abnormal findings in 0 of 13 (0%) low ASGES and 10 of 71 (14%) elevated ASGES patients. Major adverse cardiovascular events and revascularization were noted in 3/252 (1.2%) patients with low ASGES and 14/314 (4.5%) patients with elevated ASGES score (P <.03). CONCLUSIONS: In this community-based cardiovascular registry, the ASGES demonstrated clinical utility in the evaluation of patients with suspected obstructive coronary artery disease. Low-score patients were less likely to undergo cardiac referral, were unlikely to have positive findings on further cardiac work-up, and had a low rate of adverse cardiovascular events in 1-year follow-up. Our work provides evidence supporting the value of using precision medicine in the delivery of cardiovascular care.

Clinical experience with a circumferential clip-based vascular closure device in diagnostic catheterization.

BACKGROUND: The StarClose Vascular Closure System (Abbott Vascular Devices, Redwood City, California) utilizes a small, flexible nitinol clip to complete a circumferential, extravascular closure of the femoral arteriotomy site. The StarClose is an investigational device in the United States, limited by Federal law to investigational use. The StarClose is CE Mark approved. METHODS: The CLIP study was a prospective, randomized, multicenter trial utilizing a noninferiority design to compare the rate of major vascular complications and time-to-hemostasis using the StarClose system versus manual compression. A total of 596 subjects were enrolled, 208 of whom underwent diagnostic angiography. This diagnostic subset is the focus of this report. The primary safety endpoint was major vascular complications and the primary efficacy endpoint was time-to-hemostasis. All patients were followed at 30 days with a clinical exam. RESULTS: Subjects were randomized 2:1 to the StarClose (n = 136) or manual compression (n = 72). There were no major vascular complications in either group. Minor vascular complications occurred in 3 StarClose patients (2.2%), and 1 manual compression patient (1.4%) (p = 1.00). Use of the StarClose device reduced mean time-to-hemostasis from 15.47 +/- 11.4 to 1.46 +/- 4.5 minutes (p < 0.001) when compared to manual compression, and reduced the average time-to-ambulation from 269 +/- 135 to 163 +/- 105 minutes (p < or = 0.001). Device success was 94.1% (127/135), and procedural success was 100% (136/136). CONCLUSION: The clinical results of this study concluded that the StarClose Vascular Closure System is noninferior to standard compression with respect to the the primary safety endpoint of closing arteriotomies in patients who undergo percutaneous diagnostic procedures.

Randomized trial of a medical food for the dietary management of chronic, stable angina.

OBJECTIVES: We determined the electrocardiographic, vascular and clinical effects of a medical food bar enriched with L-arginine and a combination of other nutrients known to enhance endothelium-derived nitric oxide (NO) in patients with stable angina. BACKGROUND: Enhancement of vascular NO by supplementation with L-arginine and other nutrients has been shown to have clinical benefits in patients with angina secondary to atherosclerotic coronary artery disease (CAD). However, the amounts and combinations of these nutrients required to achieve a clinical effect make traditional delivery by capsules and pills less suitable than alternative delivery methods such as a specially formulated nutrition bar. METHODS: Thirty-six stable outpatients with CAD and class II or III angina participated in a randomized, double-blind, placebo-controlled, crossover trial with two treatment periods each of two weeks' duration (two active bars or two placebo bars per day). Flow-mediated brachial artery dilation was measured by ultrasound. Electrocardiographic measures of ischemia, exercise capacity and angina onset time were measured by treadmill exercise testing and by Holter monitor during routine daily activities. Quality of life was assessed by SF-36 and Seattle Angina Questionnaires and by diary. RESULTS: The medical food improved flow-mediated vasodilation (from 5.5 +/- 4.5 to 8.0 +/- 4.9, p = 0.004), treadmill exercise time (by 20% over placebo, p = 0.05) and quality-of-life scores (SF-36 summary score; 68 +/- 13 vs. 63 +/- 21 after placebo, p = 0.04, Seattle Angina Questionnaire summary score; 67 +/- 10 vs. 62 +/- 18, p = 0.04) without affecting electrocardiographic manifestations of ischemia or angina onset time. CONCLUSIONS: These findings reveal that this arginine-rich medical food, when used as an adjunct to traditional therapy, improves vascular function, exercise capacity and aspects of quality of life in patients with stable angina.