Left ventricular dysfunction in Duchenne muscular dystrophy

Abstract

<jats:title>Abstract</jats:title><jats:sec id="S1047951119002610_as1" sec-type="other"><jats:title>Background:</jats:title><jats:p>Duchenne muscular dystrophy is associated with progressive cardiorespiratory failure, including left ventricular dysfunction.</jats:p></jats:sec><jats:sec id="S1047951119002610_as2" sec-type="other"><jats:title>Methods and Results:</jats:title><jats:p>Males with probable or definite diagnosis of Duchenne muscular dystrophy, diagnosed between 1 January, 1982 and 31 December, 2011, were identified from the Muscular Dystrophy Surveillance Tracking and Research Network database. Two non-mutually exclusive groups were created: patients with ≥2 echocardiograms and non-invasive positive pressure ventilation-compliant patients with ≥1 recorded ejection fraction. Quantitative left ventricular dysfunction was defined as an ejection fraction &lt;55%. Qualitative dysfunction was defined as mild, moderate, or severe. Progression of quantitative left ventricular dysfunction was modelled as a continuous time-varying outcome. Change in qualitative left ventricle function was assessed by the percentage of patients within each category at each age. Forty-one percent (n = 403) had ≥2 ejection fractions containing 998 qualitative assessments with a mean age at first echo of 10.8 ± 4.6 years, with an average first ejection fraction of 63.1 ± 12.6%. Mean age at first echo with an ejection fraction &lt;55 was 15.2 ± 3.9 years. Thirty-five percent (140/403) were non-invasive positive pressure ventilation-compliant and had ejection fraction information. The estimated rate of decline in ejection fraction from first ejection fraction was 1.6% per year and initiation of non-invasive positive pressure ventilation did not change this rate.</jats:p></jats:sec><jats:sec id="S1047951119002610_as3" sec-type="other"><jats:title>Conclusions:</jats:title><jats:p>In our cohort, we observed that left ventricle function in patients with Duchenne muscular dystrophy declined over time, independent of non-invasive positive pressure ventilation use. Future studies are needed to examine the impact of respiratory support on cardiac function.</jats:p></jats:sec>

Direct costs of adhering to selected Duchenne muscular dystrophy Care Considerations: Estimates from a midwestern state

“…We estimated cumulative frequencies using published averages for ages at diagnosis (5 years), [21][22][23] loss of independent ambulation (11 years), 22,23 onset of left ventricular dysfunction (15 years), 24 and death (25 years). 23,25 In addition, glucocorticoids (0.75 mg mg/kg per day of prednisone or 0.90 mg/kg/day of deflazacort) and prophylactic cardiac medication (lisinopril: 2.5 mg/day for those up to 40 kg, 5 mg/day for those ≥40 kg) 26 were assumed to be initiated at 8 years of age.…”

The role of the dystrophin glycoprotein complex in muscle cell mechanotransduction

“…The extent of DCM in patients with DMD is almost ubiquitous by late teens (90% by 18 yrs), but is present in approximately 59% of patients by 10 yrs 8 , 22 . It is critically important to address this issue as left ventricular ejection fraction steadily declines annually at a rate of 1.6% per annum 23 .…”

Assessing the effect of non-invasive ventilation on cardiac function in Duchenne muscular dystrophy requires prospective studies

“…With interest, we read the article by James et al about a study on the effect of non-invasive positive pressure ventilation on cardiac dysfunction in patients with Duchenne muscular dystrophy, assessed as ejection fraction <55% or fractional shortening <28%. 1 When comparing 140 Duchenne muscular dystrophy patients under full/complete non-invasive positive pressure ventilation (cohort-2) with 403 Duchenne muscular dystrophy patients (cohort-1), non-invasive positive pressure ventilation had no beneficial effect on ejection fraction/fractional shortening. 1 The study has a number of shortcomings.…”

“…1 When comparing 140 Duchenne muscular dystrophy patients under full/complete non-invasive positive pressure ventilation (cohort-2) with 403 Duchenne muscular dystrophy patients (cohort-1), non-invasive positive pressure ventilation had no beneficial effect on ejection fraction/fractional shortening. 1 The study has a number of shortcomings.…”

“…That cohort-1 included non-invasive positive pressure ventilation patients is substantiated by the fact that a mean age at initiation of non-invasive positive pressure ventilation is provided. 1 If the goal was to assess the effect of non-invasive positive pressure ventilation on ejection fraction/fractional shortening, a group under non-invasive positive pressure ventilation needs to be compared with a group without non-invasive positive pressure ventilation.…”