The goal of this prospective cohort study is to investigate cardiac comorbidity in a random sample of approximately 1200 patients from a population of outpatients with rheumatoid arthritis and axial spondyloarthritis referred to collectively as inflammatory arthritis (IA). The main questions it aims to answer are: * Using conventional echocardiography, the investigators aim to determine the prevalence of overt and asymptomatic cardiac dysfunction in a large random sample of outpatients with IA. Cardiac dysfunction will be evaluated by echocardiography and cardiac biomarkers (NT-pro-BNP, hs-TNT and hs-CRP). * In patients without known heart disease: Using 2, 5 and 10 year follow-up, the investigators aim to examine if advanced echocardiography can be used to detect early signs of heart disease by investigating the clinical significance of adding deformation measures - alone and in combination with selected biomarkers - to conventional risk factors in the cardiac risk assessment of patients with IA Participants will undergo an echocardiographic examination in combination with a general health assessment including obtainment of cardiac biomarkers and a electrocardiogram. Using advanced echocardiography - Tissue Doppler Imaging, 2- dimensional speckle tracking echocardiography, 3D-echocardiography and 3-dimensional speckle tracking echocardiography - the investigators also aim to compare myocardial deformation parameters of patients with IA to a gender and age matched control group without IA from the Copenhagen City Heart Study.