Multi-marker strategy of natriuretic peptide with either conventional or high-sensitivity troponin-T for acute coronary syndrome diagnosis in emergency department patients with chest pain: from the "Rule Out Myocardial Infarction using Computer Assisted Tomography" (ROMICAT) trial.
BACKGROUND
Compared to troponin alone, a dual-marker strategy with natriuretic peptides may improve acute coronary syndrome (ACS) diagnosis with a single blood draw and provide physiologic information regarding underlying heart disease. We evaluate the value of adding natriuretic peptides (myocyte stress markers) to troponins (myocardial injury markers) for diagnosing ACS in emergency department patients with chest pain.


METHODS
In 328 patients (53 ± 12 years, 63% men) with an initially negative conventional troponin and nonischemic electrocardiogram who underwent 64-slice cardiac computed tomography (CT), we measured conventional troponin-T (cTnT), high-sensitivity troponin-T (hsTnT), N-terminal pro-B type natriuretic peptide, and mid-regional pro-atrial natriuretic peptide. ACS was defined as myocardial infarction or unstable angina. CT was evaluated for coronary plaque, stenosis, and regional wall motion abnormality.


RESULTS
Patients with ACS (n = 29, 9%) had higher concentrations of each biomarker compared to those without (all P < .01). Adding natriuretic peptides, especially N-terminal pro-B type natriuretic peptide, to both cTnT or hsTnT improved the C-statistics and net reclassification index for ACS, largely driven by correctly reclassifying events. Dual-negative marker results improved sensitivity (cTnT 38% to 83%-86%, hsTnT 59% to 86%-90%; all P < .01) and negative predictive value (cTnT 94% to 97%-98%, hsTnT 96% to 97%-98%) for ACS. Patients with dual-negative markers had the lowest percentage of CT coronary plaque, stenosis, and regional wall motion abnormality (all P-trend <.001).


CONCLUSIONS
Among emergency department patients with low-intermediate likelihood of ACS, combining natriuretic peptides with either conventional or highly-sensitive troponin improved discriminatory capacity and allowed for better reclassification of ACS, findings supported by structural and functional CT results.
Division of Cardiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA. qtruong@partners.org
Quynh A
QA
Truong
James
J
Bayley
Udo
U
Hoffmann
Fabian
F
Bamberg
Christopher L
CL
Schlett
John T
JT
Nagurney
Wolfgang
W
Koenig
James L
JL
Januzzi
D054058:Acute Coronary Syndrome / Q000175:diagnosis*; D000328:Adult; D009320:Atrial Natriuretic Factor / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D002637:Chest Pain / Q000209:etiology*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D020097:Natriuretic Peptide, Brain / Q000097:blood; D045265:Natriuretic Peptides / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D020107:Troponin T / Q000097:blood
D015415:Biomarkers; D045265:Natriuretic Peptides; D010446:Peptide Fragments; D020107:Troponin T; C552580:midregional pro-atrial natriuretic peptide, human; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor