Effect of Systemic Sclerosis on Left Ventricular Long-axis Motion and Left Ventricular Mass Assessed by Magnetic Resonance

The aim of this study was to assess the effect of scleroderma on left ventricular mass and subendocardial function using cardiovascular magnetic resonance (CMR) to determine parameters reflecting early dysfunction from fibrosis. Fifteen patients with a history of scleroderma had left ventricular mass measured with standard techniques and regional subendocardial contractile function assessed using myocardial velocity mapping in the basal short-axis plane with long-axis sensitized velocity mapping. Peak myocardial velocities in systole and diastole were measured to reflect systolic and diastolic function. The variance in the regional myocardial velocity, was determined as a parameter of function heterogeneity around the ventricle. The results were compared with 19 healthy volunteers without a history of cardiovascular disease. In 10 patients, pulmonary transfer factor was measured using a single-breath helium dilution technique. The duration of scleroderma correlated with left ventricular mass (r = 0.7, p < 0.05), the coefficient of variation of velocity (r = 0.63, p < 0.05), and inversely with the mean left ventricular diastolic long-axis velocity (r = -0.63, p < 0.05). There was also a correlation between left ventricular diastolic long-axis velocity and the pulmonary transfer factor (r = 0. 7, p < 0.05). Trends suggested differences between control subjects and scleroderma patients for mean systolic (64 vs. 49 mm/sec, p = 0.09) and diastolic (90 vs. 72 mm/sec, p = 0.07) velocities, as well as velocity variance (26 vs. 33, p = 0.09). In conclusion, there is a relationship between duration of scleroderma and both left ventricular mass and diastolic function, which may result from increased myocardial fibrosis. Trends suggest absolute differences in functional values with control subjects that reflect impaired diastolic and systolic function, with greater regional heterogeneity that is consistent with nonuniform collagen deposition, but a larger sample size is required to confirm this. CMR should be explored further as a technique for monitoring myocardial involvement in scleroderma noninvasively.