Laboratory tests in patients with<unk>  degree AV block include checking the levels of serum electrolytes as calcium, magnesium and potassium. Myocarditis related lab tests as lyme titres, HIV tests, PCR for enteroviruses, and Chagas titres should be done also.
Second degree AV block laboratory findings
Right bundle branch block laboratory findings
AVNRT risk factors
AVNRT laboratory findings
Atrioventricular block laboratory findings
Third degree AV block classification
Sick sinus syndrome electrocardiogram
First degree AV block classification