A Rare Case of High-Grade Atrioventricular Block in Granulomatosis With Polyangiitis.

Granulomatosis with polyangiitis (GPA) is an autoimmune disease that affects small and medium-sized vessels. It is classically known to present with renal and respiratory tract symptoms. However, the disease can manifest in other organ systems, especially cardiovascular involvement. Though there are multiple reports of cardiac involvement in GPA, it is not commonly evaluated and is often overlooked in patients with GPA. Heart disease in GPA has a wide range of presentations ranging from subacute and silent to severe abnormalities, which can prove fatal if not identified and treated appropriately. Identifying cardiac involvement early in patients with no apparent signs can help with prevention strategies and follow-up to avoid significant complications. Pericarditis is the most common pathology noted in GPA, followed by cardiomyopathy, coronary artery disease, valvular disease, and conduction abnormality. In our report, we present a case of GPA in a young male with asymptomatic conduction abnormality of the heart. Although it was silent at the presentation, identifying the initial electrocardiogram (ECG) changes prompted us to admit him to the telemetry floor. Continuous telemetry monitoring helped us identify the progression of the conduction abnormality, which otherwise could have been missed. This led us to correlate to his symptoms which he later developed during his admission course. His symptoms subsided after prompt treatment. If not identified early, these cardiac abnormalities can delay management, leading to increased disease burden and morbidity. Hence, essential cardiac work with at least ECG and continuous telemetry monitoring is recommended.