An electrocardiogram, or ECG, is used to differentiate between the different types of<unk> . In<unk> , there is a disruption between the signal traveling from the atria to the ventricles. This results in abnormalities in the PR interval, as well as the relationship between P waves and QRS complexes on the ECG tracing. If the patient is symptomatic from their suspected<unk> , it is important that an ECG is also obtained while having symptoms. Physicians may also order a continuous ECG (i.e. Holter monitor or implanted cardiac monitor) to monitor the patient for symptoms and conduction abnormalities over a longer period of time, as<unk> s can be intermittent. Because some types of<unk>  can be associated with underlying structural heart disease, patients may also undergo echocardiogram to look at the heart and assess the function. Laboratory diagnosis for<unk> s include electrolyte, drug level and cardiac enzyme level tests. Based upon clinical suspicion, the physician may do lab tests to assess for reversible causes of<unk> , such as hypothyroidism, rheumatologic disorders, and infections (such as Lyme disease).
Atrioventricular block
Left bundle branch block
Right bundle branch block
Sinoatrial block
Ectopic beat
Bundle branch block
Sinus arrhythmia
Junctional tachycardia