A 49-year-old otherwise healthy male presented to an outside hospital with sudden onset of chest pain. Pain started the night prior while the patient was resting. He says that he had a stressful day at work as an IT specialist. Pain was substernal and across entire chest with a "squeezing" feeling. It did not radiate outside of his chest. He denies having similar symptoms prior to this episode. The pain was increased with deep breaths or excessive movement. Other than a 45- minute commute to the suburbs each day for work, he denies any recent travel. He denies any recent illnesses. He recently started playing in a tennis league but denies any recent injuries. He tried Tylenol and some over the counter antacids without relief. He presented to the emergency department the next morning when CP had not resolved overnight.
Review of Systems
Negative for shortness of breath, dizziness/lightheadedness, syncope, diaphoresis, nausea/vomiting, recent fever/chills, night sweats. Positive for 40 lbs weight loss over the past 6 months.
He has been intermittently exercising 2-3 times weekly. He smokes half a pack of cigarettes a day. He has a past history of cocaine use.
Father had myocardial infarction at age of 60.
On physical exam the patient seemed uncomfortable. Vital signs showed temp 98F, BP 114/60 mmHg, HR 80 bpm, RR 20/min, SPO2 100% on RA. ECG is shown in Figure 1. CXR was normal. Labs: BUN 16, Cr 0.5. CBC 5, Hgb13, Plt 170. Troponin: 0.021 ng/mL (normal 0-0.05).
ECG is shown in Figure 1. The patient underwent an emergent coronary angiogram which demonstrated moderate lesions in the mid LAD and mid RCA which were negative by fractional flow reserve. A transthoracic echocardiogram showed normal left ventricular ejection fraction, no pericardial thickening or effusion.
Additional labs showed: Hep C Antibody Neg, HIV negative, TB Quantiferon negative, ANA undetectable, CRP 6.5 (normal 0-0.8) TSH 0.02 (normal 0.35-4), FT4 5.0 (normal 0.6-1.7), FT3 15.0 (normal 2.4-4.2).
Figure 1: Initial Presenting ECG
The etiology of this patient's clinical presentation can be best explained by which of the following: