Prevalence and Determinants of Subclinical Cardiovascular Dysfunction in Adults With Type 2 Diabetes Mellitus

A 24-hour blood pressure monitor will be worn at the end of the visit to the following day.

Watch worn to collect free living physical activity data for 7 days.

Collection of blood samples from each participant to characterise the participant's health status and to develop a proteomic signature of early heart failure.

CMR scanning performed on a 3T MRI scanner. Standardised protocol incorporating cine functional assessment to determine LV mass, systolic function and left atrial volumes; global systolic strain and diastolic strain rates will be assessed by tagging and with tissue tracking analysis from cine images, adenosine rest and stress myocardial perfusion to assess reserve index and qualitative perfusion defects as previously described, aortic distensibility and pulse wave velocity to measure aortic stiffness, delayed contrast enhancement for assessment of LV fibrosis and evidence of previous myocardial infarction. Myocardial and liver triglyceride content will be assessed using the modified Hepafat® sequence or 1H MR spectroscopy at the inter ventricular septum. DIXON technique for the quantification of visceral adiposity and subcutaneous adipose tissue.

Comprehensive transthoracic echocardiography, including: tissue Doppler indices of diastolic filling and speckle tracking for systolic and diastolic strain/strain rate, exclusion of valvular abnormalities, assessment of LV size and function.

Computed Tomography coronary calcium scoring to assess the presence of subclinical atherosclerosis and allow an estimate of atheroma burden in addition to epicardial adipose tissue characterisation and systolic strain.

Physician supervised incremental symptom limited cardiopulmonary exercise tolerance test with ECG and haemodynamic monitoring.

A subset of the participants will have cardiac MRI scanning with manganese-based contrast agent, lasting approximately 45-50 minutes. After localisers, baseline functions and native T1 maps have been acquired, Mangafodipir (0.1mL/kg) will be administered intravenously at 1ml/min, with additional T1 maps acquired every 2.5 min after administration of the contrast agent for up to 30 minutes.