Second-Degree Atrioventricular Blocks: Take It Easy
Second-degree atrioventricular (AV) blocks are frequently observed in clinical practice and often require a pacemaker implantation, especially if the patient is symptomatic for syncope, pre-syncope, fatigue, or dyspnea. In asymptomatic patients, however, sometimes the conduction delay may be benign. This is the case of supra-hisian AV blocks (localized within the AV node) or vagally mediated AV blocks (due to parasympathetic influence and usually associated with bradycardia). Some AV blocks found in athletes’ ECGs can also be considered as normal variant. The surface ECG could represent an essential tool to diagnose the type of conduction delay.
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