A physician can diagnose AV block by examining a patient’s medical history, giving a physical exam, and evaluating blood samples for electrolyte imbalances, the presence of enzymes associated with cardiac arrest, and abnormal levels of certain medications. Most significantly, an EKG will determine the presence and extent of AV block. In an EKG, the "P" wave occurs first, and represents the electrical impulse traveling through the upper, atrial chamber, while the "QRS" wave follows, and signifies the impulse reaching the lower, ventricle chambers. The skipped beat typical of second degree AV block, for example, would visualize as a "P" wave without the following "QRS" wave. In third degree, there would be no causal relationship between the generation of "P" and "QRS" waves.
Treatment varies depending on the severity of the existing problem. Often, the less severe forms of the condition can be addressed by correcting the underlying problems, such as an electrolyte imbalance or medication overdose. For more serious cases, portable heart monitors may be used to record and monitor abnormal activity, while third degree block always requires immediate implantation of a pacemaker.
