J.V., a 56-year-old delivery truck driver, has been taken to the
emergency department (ED) because he was experiencing chest pain.
It started just after he had a quick lunch at a food truck. He told
the paramedic that he often has chest pain but that it goes away
when he "takes a swig of antacid," but this time the pain did not
stop. On arrival he was given another dose of antacid and
sublingual nitroglycerin, and the chest pain stopped. The first set
of cardiac enzymes and basic metabolic profile (BMP) were drawn,
and a 12-lead ECG was done. He weighs 275 pounds (125 kg), is 5 ft,
5 inches (165 cm) tall, and tells the nurse he has been overweight
all his life. He said he'd had the chest pains for about 2 years
but did not go to get checked because they always went away when he
took antacids and he was too busy with work to go to a doctor. He
works late hours, "lives on coffee," and grabs fast food when he
has time to eat. He smokes 1.5 to 2 packs of cigarettes a day, has
a beer every evening once he is home, and usually finishes a 6 pack
on the weekends. Vital signs: T 98.9o F (37.2o C), P 110, R 14, BP
148/98. The test results are listed below.
TEST RESULTS
Sodium: 142 mEq/L (142 mmol/L)
Potassium: 4.1 mEq/L (4.1 mmol/L)
Chloride: 102 mEq/L (102 mmol/L)
CO2: 28 mEq/L (28 mmol/L)
Glucose: 168 mg/dL (9.3 mmol/L)
BUN: 12 mg/dL (4.3 mmol/L)
Creatinine: 1.1 mg/dL (97 mcmol/L)
Calcium: 5.1 mg/dL (1.28 mmol/L)
Hemoglobin: 14.8 g/dL (148 g/L)
Hematocrit: 48%
Cardiac troponin T: 0.05 ng/mL (0.05 mcg/L)
12-Lead ECG: Sinus tachycardia, rate 105
Six hours later, the
second set of cardiac enzymes was normal. Do you think J.V. has had
a myocardial infarction (MI)? Defend your answer.