Evaluating myocardial involvement in patients with multiple myeloma at different stages a cardiac MR T1 mapping study

Abstract Background At present, the International criteria for diagnosis multiple myeloma（MM） do not specifically highlight the use of cardiac magnetic resonance (CMR) to detect abnormal myocardial infiltration in patients at different clinical stages of MM. Extracellular volume fraction (ECV) based on CMR T1 mapping indicates expansion of the extracellular space or deposition of material in infiltrative heart diseases. Purpose To detect whether myocardial involvement in patients with MM at different clinical stages based on CMR T1 mapping. Methods A cohort consisting of 20 patients with diagnosed MM and 15 sex- and age-matched controls (Cs) were recruited for this study. All participants underwent CMR examination to obtain native T1 and ECV. The patients with MM were stratified into three groups based on the International Staging System (ISS): Stage I (n=5), Stage II (n=7), and Stage III (n=8). Cardiac amyloidosis (CA) is diagnosed based on the patient's clinical presentation and tissue biopsy. The baseline biochemical indices were collected before CMR examination. Result Among patients with MM, there were a total of 9 patients diagnosed with CA, comprising 3 patients in stage II and 6 patients in stage III. The ECV in stage III patients (45.13±11.89%) was significantly higher compared to that in stage I (26.65±4.22%), stage II (34.09±8.90%), and controls (25.40±2.52%) (p < 0.05). Furthermore, the ECV in stage II patients (34.09±8.90%) was higher compared to controls (25.40±2.52%), though not significantly different from stage I patients (26.65±4.22%). Correlation analysis revealed a positive correlation between brain natriuretic peptide (BNP) levels and ECV (r=0.606, p=0.013). Receiver operating characteristic (ROC) curve analysis demonstrated that ECV had good predictive value for CA, with an area under the curve (AUC) of 0.898 (p < 0.01), and the optimal cutoff value for ECV was determined to be 33.7%. Conclusions ECV derived from CRM T1 mapping holds promise for identifying amyloid accumulation, which deteriorates progressively with the advancement of disease stages in patients with MM. It is recommended that patients diagnosed with Stage II and Stage III MM should undergo CMR to facilitate the early detection of myocardial infiltrative damage.