Mr. Reed is a 69-year-old retired teacher who is admitted to the emergency department because of severe chest pain. He reports that the pain started about an hour ago while he was mowing his lawn and is radiating to his left arm, left shoulder, and neck. In the ambulance he was given Aspirin 300 mg tablet to chew and sublingual nitrate (2 doses). His medical history includes hypertension for more than 18 years and more than 50 years of smoking. His regular medications are nifedipine and aspirin.

On examination:

• Height: 182 cm, Weight: 103 kg, BMI: 31.1
• BP: 165/95 mmHg, Heart Rate: 102/min, Respiratory Rate: 24 /min, Temperature: 37.2 C, OSAT: 92%
• Skin: Pale and sweaty, cold to touch. Anxious
• ECG on admission: elevated ST segment in I, aVL, and V3-V6.

What are the above described ECG changes characteristics for?

Mr. Reed’ s laboratory investigation showed:

• Blood analysis:
  • CBC:
    • RBCs: 4.9 x 10¹²/L, Hemoglobin: 156 g/L, Hematocrit: 0.44
    • MCV: 94 fL, MCH: 32 pg, RDW: 11.9%, Reticulocytes: 1.8%, ESR: 18 mm/hour
    • WBC: 10.6 x 10⁹/L, (Neutrophils: 7.2 x 10⁹/L, Lymphocytes: 4.3 x 10⁹/L, Basophils: 0.1 x 10⁹/L, Eosinophils: 0.45 x 10⁹/L, Monocytes: 1.0 x 10⁹/L)
    • Platelet counts: 392 x 10⁹/L
  • Na: 139 mmol/L, K: 3.9 mmol/L, Cl: 98 mmol/L
  • Glucose: 6.0 mmol/L, Creatinine: 105.2 µmol/L, Uric acid: 312 mmol/L
  • Triglycerides: 3.7 mmol/L, Cholesterol: 6.6 mmol/L, HDL: 1.0 mmol/L, LDL: 4.2 mmol/L, (TC/HDL-C): 6.6
• Urinalysis:
  • Color: yellow, pH: 5.6, Specific gravity: 1024, Osmolarity : 843 mOsm/kg; Glucose, Ketones, Albumin, Bilirubin, Urobilinogen: negative, Nitrates:+, WBCs, RBCs: 2, 4/HPF, Phosphate crystals, Yeast, Bacteria: negative, Squamous epithelial cells: negative

Beside the above laboratory tests, what other tests can be performed to assist the diagnosis of myocardial infarction: (select all that apply)

Mr. Reed’ s cardiac markers showed the following values 4, 24 and 72 hours after admission:

(to learn the normal values of these laboratory tests, please refer to the “Normal Laboratory Values” table on our website)

Laboratory test	4 hours after admission	24 hours after admission	48 hours after admission
Myoglobin	763 ug/mL	210 ug/mL	51 ug/mL
cTnI:	1.8 ng/mL	32 ng/mL	14 ng/mL
cTnT	1.6 ng/mL	26 ng/mL	19 ng/mL
Total CK	470 U/L	634 U/L	198 U/L
CK-MB	7 ug/L	15 ug/L	6 ug/L
AST	63 U/L	109 U/L	55 U/L

Which one of these biomarkers can be seen to increase the earliest in myocardial necrosis?

Have a look at Mr. Reed’ s laboratory results again:

• Blood analysis:
  • CBC:
    • RBCs: 4.9 x 10¹²/L, Hemoglobin: 156 g/L, Hematocrit: 0.44
    • MCV: 94 fL, MCH: 32 pg, RDW: 11.9%, Reticulocytes: 1.8%, ESR: 18 mm/hour
    • WBC: 10.6 x 10⁹/L, (Neutrophils: 7.2 x 10⁹/L, Lymphocytes: 4.3 x 10⁹/L, Basophils: 0.1 x 10⁹/L, Eosinophils: 0.45 x 10⁹/L, Monocytes: 1.0 x 10⁹/L)
    • Platelet counts: 392 x 10⁹/L
  • Na: 139 mmol/L, K: 3.9 mmol/L, Cl: 98 mmol/L
  • Glucose: 6.0 mmol/L, Creatinine: 105.2 µmol/L, Uric acid: 312 mmol/L
  • Triglycerides: 3.7 mmol/L, Cholesterol: 6.6 mmol/L, HDL: 1.0 mmol/L, LDL: 4.2 mmol/L, (TC/HDL-C): 6.6

Which of the following laboratory values are particularly important to consider when Mr. Reed’ s long-term treatment is planned? (select all that apply)