A 60-year-old with heart failure symptoms due to 1st degree AV-Block caused by granulomatosis with polyangiitis (Wegener's granulomatosis).

Granulomatosis with polyangiitis is a rare systemic inflammatory disorder mainly affecting the small vessels. Cardiac involvement is rare, conduction delay being the most rare one. This case reports on a middle-aged male patient with heart failure symptoms due to a 1st degree atrioventricular block with a marked PR prolongation of 480 ms on electrocardiography (ECG). Because of heart failure symptoms as well as elevated N-terminal pro-B-type natriuretic peptide and no other relevant findings in the blood test it was initially planned to treat the conduction disorder with a pacemaker. During further investigations a certain diagnosis of granulomatosis with polyangiitis was determined. After administration of high-dose steroids a complete clinical remission of heart failure symptoms and normal conduction on ECG were demonstrated, so that no pacemaker therapy was needed. <Learning objective: Although atrioventricular (AV) conduction disorders have been described previously in patients with granulomatosis with polyangiitis, this is the first case reporting of vasculitis causing heart failure symptoms due to non-severe conduction disorder such as 1st degree AV-block. Even in the case of non-severe AV conduction delay, which causes symptoms, it is essential to investigate possible rare causes of the conduction disorder before considering pacemaker treatment.