Aims
Heart disease is recognized as the leading cause of morbidity and mortality in patients with muscular dystrophy (MD). Our study demonstrates the clinical utility of cardiac biomarkers to improve the diagnosis of cardiomyopathy and prognostication of major adverse cardiac events (MACE) in these vulnerable patients.
Methods and Results
We prospectively followed 117 patients (median age, 42 (interquartile range [IQR], 26-50) years; 49 [41.9%] women) at the Neuromuscular Multidisciplinary clinic diagnosed with a dystrophinopathy, limb-girdle MD, type 1 myotonic dystrophy, or facioscapulohumeral MD. We determined that B-type natriuretic peptide (BNP) and high-sensitive troponin I (hsTnI) were effective diagnostic markers of cardiomyopathy (area under the curve [AUC], 0.64; P=0.017; and AUC, 0.69; P=0.001, respectively). Patient risk stratification for MACE was based on cutoff values of BNP and hsTnI defined a priori as 30.5000 pg/mL and 7.6050 ng/L, respectively. Over a median follow-up period of 2.09 (IQR, 1.17-2.81) years there were 36 confirmed MACE. Multivariate regression analyses showed that patients with BNP and hsTnI levels above the respective cutoff values had a 3.70-fold (P=0.001) and 3.24-fold (P=0.002) greater risk of MACE, respectively, compared to patients with biomarker levels below. Furthermore, patients with biomarker levels above both cutoff values had a 4.08-fold (P=0.001) greater risk of MACE. Inflammatory biomarkers did not show clinical utility for heart disease in these patients.
Conclusion
Our study demonstrates important diagnostic and prognostic value of BNP and hsTnI as part of a comprehensive cardiac assessment to augment the management and treatment of heart disease in patients with MD.