Clinical features and Diagnosis of Unstable Angina(UA) / NSTEMI with Cardiac Biomarkers in Angina

Clinical features of Unstable Angina(UA) / NSTEMI —

  • There is chest pain in the substernal lesion or epigas­trium radiating to neck, left shoulder and left arm.
  • There is severe discomfort or pain.
  • Anginal equivalents like dyspnoea and epigastric dis­comfort are also frequently present.
  • There is diaphoresis (increased sweating), pale skin, sinus tachycardia, third and fourth heart sound, basi­lar rales or crepts, sometime hypotension.

Unstable Angina 1

Clinical features of Unstable Angina(UA) / NSTEMI

ECG Unstable Angina(UA) / NSTEMI —

  • There is ST segment depression
  • Rarely there is transient ST segment elevation
  • There may be T inversions
  • Any new ST segment changes like depression of even 0.05 mV may denote increasing severity.
  • New deep T wave inversions (more than 0.3 mV) may be significant, but usually T wave changes are non­specific.

Cardiac Biomarkers Unstable Angina(UA) / NSTEMI

  • CK-MB and troponin (highly specific) are elevated in MI and associated with increased risk of death.
  • 7In UA the cardiac biomarkers are not elevated.
  • In NSTEMI the cardiac biomarkers are elevated. Minor elevations of troponin can occur in heart fail­ure, myocarditis, pulmonary embolism
  • or may be false positive. Therefore it is suggested that when the presentation is of ACS only then tropo­nin test may be done.
  • New cardiac markers are C-reactive protein, BNP (B type nitriuretic peptide, CD-40 ligand etc. )

Diagnosis of Unstable Angina(UA) / NSTEMI

  • The diagnosis is established by typical ischemic dis­comfort, history of CAD, old angiography, old MI, ECG changes, elevated cardiac biomarkers like troponin stress testing.
  • IQhe cardiac markers are negative on admission then it may be repeated at 6 and 12 hours after presentation.
  • AII the patient with elevated cardiac markers and ECG changes should be admitted to the hospital.
  • If the patient is pain free and the markers are nega­tive then patient should undergo stress testing in 72 hours. For atients who cannot walk, Dobutamine stress test should be done (non-exercise or- pharmacologicaI stress test). –
  • Echocardiography should also be done for most pa­tients.
  • For myocardial perfusion, sestamibi or thallium im­aging is done. This test shows whether there is myo­cardial damage and non-viable myocardial.