Introduction Here we report a challenging case of a rare systemic condition – immunoglobulin G4-related disease (IgG4-RD) – that presented with a rare cardiovascular manifestation. Aortitis due to IgG4-RD is well-documented in the literature, but rarely has it been related to the involvement of the coronary arterial tree. We documented IgG4-RD with diffuse coronary periarteritis, presenting as acute heart failure in this particular case. Despite the initial severity, multidisciplinary teamwork was the key to expeditious diagnosis and initiating tailored life-saving […]