Background: Gadolinium-enhanced cardiovascular magnetic resonance (CMR) is the most widely used approach for diagnosing myocardial fibrosis with late gadolinium enhancement (LGE) in cardiomyopathy associated with Duchenne muscular dystrophy. Given the limitations and safety of gadolinium use, we wanted to develop and evaluate multi-parametric pre-contrast CMR models for the diagnosis of LGE and investigate whether they could be utilised as surrogates for LGE in DMD patients.

Methods: A total of 136 DMD patients were prospectively recruited and separated into LGE− and LGE+ groups. In the first subset of patients (derivation cohort), regression models for the diagnosis of LGE were built by logistic regression using pre-contrast sequence parameters. In a validation cohort of other patients, the models’ performances were evaluated.

Results: EF, native T1 and longitudinal strain alone, as well as their combinations form seven models. The model that included EF, native T1 and longitudinal strain had the best diagnostic value, but there was no significant difference in diagnostic accuracy among the other models except EF. In the validation cohort, the diagnosis outcomes of models were moderate consistent with the existence of LGE. The longitudinal strain outperformed the other models in terms of diagnostic value (sensitivity: 83.33%, specificity: 54.55%).

Conclusions: Pre-contrast sequences have a moderate predictive value for LGE. Thus, pre-contrast parameters may be considered only in a specific subset of DMD patients who cannot cooperate for long-time examinations and have contradiction of contrast agent to help predict the presence of LGE.

DMD is a fatal X-linked recessive muscular degenerative disorder caused by defective dystrophin synthesis, resulting in fibrosis and fat replacement of muscles throughout the body, including skeletal and cardiac muscles, and affects 1 in about every 3500–5000 boys [1]. Most patients die of cardiopulmonary failure in their second to third decades, but with the development of clinical non-invasive mechanical ventilation technology, the risk of death from respiratory failure has been significantly lowered [2] and cardiomyopathy has become the leading cause of death in DMD patients [3].

Non-invasive cardiovascular imaging is indispensable for the early detection of myocardial abnormalities, which can develop early in DMD patients [4]. Currently, CMR has gradually become the preferred imaging technique for cardiac monitoring in DMD patients [5-6]. LGE of CMR can identify myocardial abnormalities and assess fibrosis before LV dysfunction occurs [7-8]. Cardiac function in DMD patients with LGE is poorer and declines more quickly than in those without LGE [9]. Furthermore, the existence of LGE is also associated with a significantly increased risk of unfavourable outcomes in DMD patients, including arrhythmias, hospitalization for heart failure and cardiogenic death [8, 10-11]. Thus, early aggressive management and monitoring of possible LGE before impending LV dysfunction are critical for improving the prognosis of DMD patients. However, DMD patients with abnormal renal function cannot finish this examination because of the renal excretion of GBCAs, essential for LGE imaging [12]. In a small number of people, GBCAs might cause an allergy, resulting in adverse consequences [13]. In addition, GBCAs are also known to deposit in the brain, bones and other organs; there are still concerns regarding the safety of GBCAs in children [14-15]. As most DMD patients are children and their conditions are often serious, compared with other patients, they are often unable to cooperate for a long time owing to their young age, dyskinesia, scoliosis and other defects caused by disease. As a result, shortening scanning time is an effective way to enhance patient compliance while also obtaining images in good quality. Considering all the above reasons, it is necessary and clinically significant to explore the value of pre-contrast sequences in detecting fibrosis in DMD patients.