Daniel S. Knight

The value of exercise cardiovascular magnetic resonance (CMR) has been shown in many clinical scenarios. We have developed a novel MR‐compatible exercise device and aim to validate it against the reference standard MR‐conventional ergometer. The novel device consisted of two half‐pipes fixed to a wooden base, with participants wearing knee‐length socks with a 0.5 kg weight in each sock. Increased workload was achieved by increasing the rate of alternating leg flexion and extension in time with a bleep sound of increasing frequency. Twenty subjects (10 healthy volunteers, 10 patients with pulmonary arterial hypertension) performed two CMR‐augmented cardiopulmonary exercise tests (CMR/CPET) using the novel exercise device and a conventional ergometer in a randomised order. Comparing peak metrics elicited on both exercise devices, there was a moderate correlation in peak oxygen consumption (VO ₂ , r = 0.86, p < 0.001), cardiac output (CO, r = 0.73, p < 0.001), stroke volume (SV, r = 0.90, p < 0.001), peak heart rate (HR, r = 0.65, p = 0.002) and peak arteriovenous oxygen content gradient (ΔavO ₂ , r = 0.71, p < 0.001). However, all metrics were significantly lower with the novel device. Both devices were able to elicit statistically significant differences in VO ₂ , HR and right ventricular ejection fraction (RVEF) between patients and healthy subjects ( p ≤ 0.04). We have created a simple, easy to use and affordable exercise device for the CMR environment. This may encourage greater dissemination of exercise CMR in clinical and research practice.

Objectives: Cardiac involvement in scleroderma due to myocardial inflammation and fibrosis is associated with poor outcomes, but there is lack of consensus on its investigation and treatment. In this prospective pilot study, we aimed to assess the cardiac uptake of 18F-FDG-PET/CT in suspected scleroderma cardiomyopathy. Methods: The Scleroderma Heart study involved 16 patients with cardiac scleroderma but no coronary artery disease. 18F-FDG-PET/CTs were performed, and the patients with a positive scan were offered a second 18F-FDG-PET/CT scan after 6–9 months. The clinical characteristics and clinical outcomes (all-cause mortality) were compared between the patients with positive and negative 18F-FDG-PET/CT scans. Results: Of the 16 included patients, 8 (50%) had positive myocardial uptake on the 18F-FDG-PET/CT, 2 of whom showed a pattern consistent with cardiac involvement in scleroderma, while 6 patients more likely had physiological uptake. Over a mean follow-up of 603.3 days, all-cause mortality occurred in six patients (37.5%), and the mortality was similar between the two groups. Five patients with repeat 18F-FDG-PET/CTs showed stable or increased FDG uptake despite immunosuppression. Conclusions: To the best of our knowledge, this is the first study to investigate 18F-FDG-PET/CT in scleroderma patients with suspected cardiac involvement. The cardiac PET showed limited clinical utility due to frequent physiological uptake and lack of correlation with the treatment response. Further studies with larger cohorts and standardised interpretation criteria are needed before cardiac PET can be recommended for routine clinical use in scleroderma cardiomyopathy.