News | Blood Testing | March 26, 2018

Singulex cTnl Assay Can Identify Presence, Severity of CAD in Stable, Symptomatic Outpatients

Findings from PROMISE Trial suggest potential of using cardiac troponin testing to evaluate patients outside the emergency department

Singulex cTnl Assay Can Identify Presence, Severity of CAD in Stable, Symptomatic Outpatients

March 26, 2018 — Measurement of cardiac troponin in stable patients with chest pain using the ultra-sensitive Singulex cTnI assay and Single Molecule Counting technology can independently predict moderate and severe coronary disease (CAD), according to a recent study. The results suggest the assay’s clinical utility for accurate, safe and cost-effective evaluation of patients in an outpatient setting.  

The study appears in the March issue of the Journal of the American College of Cardiology Imaging.

Cardiac troponin is a well-established biomarker currently used in hospital emergency departments to help diagnose myocardial infarction (MI) in patients who present with acute chest pain. Findings from The Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) Trial shed light on the broader potential of troponin measurement in the chronic setting.

"Chest discomfort is one of the most commonly-encountered complaints in outpatient medicine, and represents a major diagnostic challenge as patients often present with a broad range of non-specific symptoms or signs," said James Januzzi, Jr, M.D., physician in the Cardiology Division at Massachusetts General Hospital, the Hutter Family Professor of Medicine at Harvard Medical School, and senior cardiometabolic trials faculty at the Baim Institute for Clinical Research.  "Classical history and physical examination for determining cause of chest discomfort is neither sensitive nor specific to identify obstructive CAD as the cause of this common complaint. Having a diagnostic blood test to enhance ability to rapidly and accurately support clinical judgment, identify or rule-out CAD would address these challenges," he said.

With up to 1,000 times more sensitivity than existing technologies, according to Singulex, Single Molecule Counting reveals the presence or absence of disease more clearly and definitively than was possible before. The Singulex cTnI assay using proprietary Single Molecule Counting technology is the first test to quantitatively measure cardiac troponin down to femtogram per milliliter levels, far lower than existing high sensitivity troponin immunoassays, enabling unprecedented insight into cardiovascular disease.

In the PROMISE trial, the Singulex cTnI assay was used to measure troponin in 1,844 outpatients with stable chest discomfort who were randomized to coronary computed tomography angiography (CTA). Investigators found concentrations of the biomarker cardiac troponin I (cTnI) associated with presence and severity of coronary artery calcium (CAC) and obstructive CAD. The median cTnI concentration was 1.5 ng/L; nearly all (98.5 percent) subjects had measurable cTnI and 6.1 percent had concentrations ≥99th percentile for this assay (6 ng/L). Higher CAC scores, as well as more prevalent and diffuse CAD was seen in upper cTnI quartiles (all P<0.001). Independent predictors of cTnI concentrations included age, sex, and CAC score (all P<0.05). After adjusting for demographic and clinical characteristics, cTnI concentrations were significantly associated with obstructive CAD50 and CAD70.

The conventional approach for evaluation of patients with suspected CAD includes stress tests with/without nuclear or echo imaging. Imaging has advantages and potential drawbacks, including low diagnostic yield, higher cost, limited availability, time lag to results, and potential patient exposure to ionizing radiation.

"Participants with higher concentrations of cTnI identified with the very highly sensitive Singulex Single Molecule Counting assay had more prevalent risk factors for coronary artery disease, and on non-invasive imaging, these higher concentrations were associated with increasing presence and severity of CAD," Januzzi continued.  "The potential to use this ultra-sensitive assay to supplement clinical decision-making could substantially enhance cardiovascular care in the outpatient setting."

For more information: www.imaging.onlinejacc.org

Related Troponin Content

VIDEO: Use of High Sensitivity Troponin Testing in the Emergency Department

Highly-sensitive Troponin Test Can Detect Myocardial Injury After Non-Cardiac Surgery

New Heart Attack Evaluation Cuts Unnecessary Tests, Time in ER

Related Content

Abbott Receives CE Mark for High Sensitive Troponin-I Test
News | Blood Testing | October 16, 2018
October 16, 2018 — Abbott announced that its High Sensitive Troponin-I...
AI-Driven Blood Test Accurately Diagnoses Peripheral Artery Disease in Diabetic Patient
News | Blood Testing | September 04, 2018
Prevencio Inc. announced new data demonstrating its HART PAD test accurately diagnoses peripheral artery disease (PAD)...
More Sensitive Blood Test Diagnoses Heart Attacks Faster
News | Blood Testing | August 06, 2018
August 6, 2018 — A new test to assess a whether or not someone is having a...
Florida Medical Center First in State to Offer High Sensitive STAT Blood Test
News | Blood Testing | September 07, 2017
In July, The Heart Institute at Florida Medical Center became the first hospital in the state of Florida to offer the U...
Patients With Low Corus CAD Test Score Less Likely to Undergo Cardiac Referra
News | Blood Testing | May 02, 2017
CardioDx Inc. recently announced the publication of results from the multi-center, community-based PRESET Registry in...
New Blood Test Predicts Major Cardiac Events Better Than Clinical Evaluation of Other Common Risk Factors
News | Blood Testing | April 28, 2017
Prevencio Inc. announced the publication of data demonstrating that a simple new blood test is more accurate than...
New Study Pursues Universal Sample Bank for Troponin Tests
News | Blood Testing | April 13, 2017
April 13, 2017 — A study published recently in the American Association for Clinical Chemistry’s (AACC)...
PTS Diagnostics, FDA 510k clearance, extended HDL range, lipid panel test strips
News | Blood Testing | April 05, 2017
PTS Diagnostics announced that the U.S. Food and Drug Administration (FDA) has cleared an expanded top range for...
heart attack evaluation, blood test, HEART Score, ER, emergency room, Circulation Cardiovascular Quality and Outcomes study
News | Blood Testing | March 01, 2017
Up to 40 percent of emergency room (ER) patients with chest pain can safely go home in a little under 2 hours, using a...
troponin blood test, heart disease risk, heart attack, British Heart Foundation, BHF
News | Blood Testing | January 04, 2017
A high-sensitivity blood test could be used to predict which patients are at risk of a heart attack according to new...
Overlay Init