Giant Cell Arteritis: Cardiac and Aortic Complications at the Cardio-Rheumatology Interface

Giant cell arteritis (GCA) is the most common primary systemic vasculitis of older adults and has traditionally been framed as an ophthalmologic emergency. Its most serious consequences, however, occur in the cardiovascular system, often years after inflammatory markers have normalized. In contemporary matched population cohorts, patients with GCA carry an approximately two-fold excess risk of aortic aneurysm; the historical Olmsted County cohort reported a 17-fold excess of thoracic aortic aneurysm with wide confidence limits, and the characteristic latency to aneurysm is five to ten years. Patients also face elevated risks of aortic dissection, myocardial infarction, stroke, venous thromboembolism, and heart failure that cluster within the first year of diagnosis, when vascular inflammation is most active. This narrative review, based on a structured search of PubMed/MEDLINE and Google Scholar through September 2026 with independent verification of every cited estimate, synthesizes current evidence on the full spectrum of cardiac and aortic complications of GCA, including aortitis, aneurysm and dissection, coronary arteritis, valvular disease, pericarditis, myocarditis, and conduction disease. We trace their common origin to the immunopathology of the arterial wall, where dendritic cell activation, Th1/Th17 polarization, and maladaptive vascular remodeling produce occlusion in medium-sized arteries and dilation in the aorta. We examine current diagnostic modalities, from the ultrasound-based fast-track clinic, which has reduced permanent visual loss by half or more in observational cohorts, to FDG-PET/CT, in which aortic uptake at diagnosis is associated with subsequent aortic dilation. We review treatment after the GiACTA and SELECT-GCA trials in the light of the 2025 European Alliance of Associations for Rheumatology (EULAR) recommendations, the unresolved role of antiplatelet and statin therapy, and the surgical and endovascular management of GCA-related aortopathy. We suggest that the organization of care, as well as the limitations of drug therapy, may contribute to the residual mortality of GCA, a hypothesis that has not been tested; distinguish recommendations that are supported by current guidelines from those that are our own proposals; and outline a cardio-rheumatology pathway in which baseline vascular phenotyping informs individualized aortic surveillance. GCA is a disease whose natural history often begins in the rheumatology clinic and ends in the cardiac operating room without prior surveillance.