Unstable Angina

Use serial high-sensitivity cardiac troponin testing together with ECG and ischemic assessment. NSTEMI requires a rise or fall in high-sensitivity troponin with at least one value above the 99th percentile and at least one ischemic correlate: ischemic symptoms, ischemic ECG changes, new Q waves, a new ischemic regional wall-motion abnormality, or intracoronary thrombus. A patient meeting these criteria should enter an NSTEMI pathway rather than retain the diagnosis of unstable angina. PubMedPubMedCurrent Management of Non-ST-Segment Elevation Acute Coronary Syndrome

Reserve unstable angina for a syndrome of clinically convincing ischemia without biomarker evidence of myocardial injury. High-sensitivity assays have reclassified a proportion of patients formerly labeled as unstable angina as MI, leaving a contemporary unstable-angina population with lower mortality and less frequent obstructive coronary disease. BMJ+2BMJPre-test characteristics of unstable angina patients with obstructive coronary artery disease confirmed by coronary angiography | Open HeartWileyClinical implications of high‐sensitivity cardiac troponinsOxford AcademicHow to use high-sensitivity cardiac troponins in acute cardiac care

Obtain the initial 12-lead ECG within 10 minutes of emergency-department arrival. New ST-segment depression, transient ST-segment elevation, or elevated troponin identifies high risk and supports an invasive NSTE-ACS approach; do not allow a later negative troponin result to negate dynamic ischemic ECG findings or ongoing ischemic symptoms. PubMedPubMedManagement of patients with unstable angina/non-ST-elevation myocardial infarction: a critical review of the 2007 ACC/AHA guidelines - PMC

Base early short-term risk assessment on symptom pattern, vital signs, physical examination, ECG findings, and high-sensitivity troponin results. Higher-risk NSTE-ACS patients derive the greatest benefit from revascularization, making correct risk assignment central to selecting invasive rather than conservative evaluation. PubMed+1PubMedCurrent Management of Non-ST-Segment Elevation Acute Coronary SyndromePubMedThe use of risk scores for stratification of non-ST elevation acute coronary syndrome patients

Use TIMI or GRACE as structured adjuncts. In an ACC/AHA-derived pathway, TIMI 0–1 was low risk, TIMI 2–3 intermediate risk, and TIMI at least 4 high risk when ECG and biomarker abnormalities were absent; patients with new ST depression, transient ST elevation, or elevated troponin were considered high risk independent of that score. PubMedPubMedManagement of patients with unstable angina/non-ST-elevation myocardial infarction: a critical review of the 2007 ACC/AHA guidelines - PMC

For patients considered to have unstable angina, a GRACE score of 109–140, relevant comorbidity, recurrent symptoms, or a positive ECG or stress test has been used to support coronary angiography within 72 hours. This is a selection framework, not proof of obstructive culprit disease. BMJBMJPre-test characteristics of unstable angina patients with obstructive coronary artery disease confirmed by coronary angiography | Open Heart

Choose invasive coronary angiography when the pretest probability of significant obstructive coronary disease causing the symptoms is high, particularly with recurrent ischemia or objective evidence on ECG or stress testing. Angiography directly defines coronary anatomy and forms the basis for revascularization decisions, but may show normal arteries, nonobstructive CAD, or single- or multivessel obstructive disease in patients presenting with unstable angina. BMJ+1BMJPre-test characteristics of unstable angina patients with obstructive coronary artery disease confirmed by coronary angiography | Open HeartScienceDirectCoronary Angiography - an overview | ScienceDirect Topics

For a clinically stable patient with non-elevated or uncertain high-sensitivity troponin, no ECG changes, and no recurrent chest pain, consider CCTA or noninvasive functional stress imaging as part of initial triage. CCTA is highly sensitive for coronary atherosclerosis but may not identify whether plaque explains symptoms when stenoses are nonobstructive; functional imaging better assesses ischemia from obstructive CAD but does not define atherosclerotic plaque burden. ScienceDirectScienceDirectCoronary computed tomography angiography versus functional stress imaging to triage chest pain in the emergency room? - ScienceDirect

Interpret a negative or nonobstructive anatomic evaluation as a diagnostic pivot rather than a false positive by default. In a CT angiography study of patients with initially negative ECG and troponin results, 9 of 40 had normal CCTA and 16 had no significant obstructive lesion; invasive angiography likewise has recognized limitations in characterizing ischemic syndromes when lesions are not clearly severe or arteries are not normal. ScienceDirect+1ScienceDirectCoronary Angiography - an overview | ScienceDirect TopicsScienceDirectRole of multi-slice CT coronary angiography in evaluating the different patterns of coronary artery disease in patients with unstable angina - ScienceDirect

When angiography identifies a severe stenotic lesion compatible with the ischemic presentation, use the angiographic result to make revascularization decisions. Angiography is particularly useful when it demonstrates either normal arteries or a severely stenotic lesion; intermediate or anatomically uncertain lesions require caution because the angiogram is a two-dimensional representation and may miss eccentric narrowing depending on imaging angle. ScienceDirectScienceDirectCoronary Angiography - an overview | ScienceDirect Topics

When CCTA or angiography shows nonobstructive CAD, do not equate the result with a definitive explanation for symptoms. CCTA identifies plaque effectively but may not provide a diagnosis because many patients lack obstructive disease; functional testing may clarify whether obstructive ischemia is present. ScienceDirectScienceDirectCoronary computed tomography angiography versus functional stress imaging to triage chest pain in the emergency room? - ScienceDirect

When the patient has persistent or recurrent ischemic symptoms despite an initially negative ECG and troponin profile, repeat the clinical assessment and reconsider an invasive strategy or objective ischemia testing. In the unstable-angina literature, recurrence of symptoms and positive ECG or stress testing are explicit triggers for coronary angiography. BMJBMJPre-test characteristics of unstable angina patients with obstructive coronary artery disease confirmed by coronary angiography | Open Heart