Blood work
Elevated troponin
Elevated BNP
Markers of inflammation such as ESR and CRP may be elevated, but are nonspecific
Elevated LFTs
Blood gas to evaluate for systemic perfusion
ECG
Sinus tachycardia is most common abnormality
Other abnormalities includes
Low voltage
Axis deviation
ST or T wave changes
AV blocks or conduction delays
Ischemic patterns
SVT or ventricular arrhythmias
CXR
Not sensitive, but often abnormal
Cardiomegaly
Pulmonary edema
Pleural effusions
Echocardiography
Unnecessary if both CXR and ECG are normal, unless you have high clinical suspicion
Elevated troponin
Elevated BNP
Markers of inflammation such as ESR and CRP may be elevated, but are nonspecific
Elevated LFTs
Blood gas to evaluate for systemic perfusion
Sinus tachycardia is most common abnormality
Other abnormalities includes
Low voltage
Axis deviation
ST or T wave changes
AV blocks or conduction delays
Ischemic patterns
SVT or ventricular arrhythmias
Low voltage
Axis deviation
ST or T wave changes
AV blocks or conduction delays
Ischemic patterns
SVT or ventricular arrhythmias
Not sensitive, but often abnormal
Cardiomegaly
Pulmonary edema
Pleural effusions
Unnecessary if both CXR and ECG are normal, unless you have high clinical suspicion
Myocarditis 
Airway obstruction
Endocarditis
Anaphylaxis
Constrictive pericarditis
Angioedema
Pericarditis
Aspirated foreign body