Left ventricular elastance as a predictor of left ventricular systolic dysfunction in neuromuscular diseases
A Fayssoil, N Mansencal, M Hauguel-Moreau, J Bergounioux, T Stojkovic, K WahbiAbstract
Background
Patients with neuromuscular diseases (NMD ) are at risk of left ventricular (LV) dysfunction. Identifying echocardiographic parameters that predict the onset of left ventricular dysfunction may help to develop preventive strategies.
Aims
To evaluate LV force (performance), related factors in NMD patients, and determine its ability to predict the onset of LV dysfunction (LV ejection fraction <50%) in those with initially preserved LV function.
Materials and methods
The study included retrospectively patients with neuromuscular diseases followed in Pitié Salpetriere hospital (Paris, France) and Raymond Poincare hospital (Garches,France) who benefied from a measurement of LV force using ultrasound. The LV force was defined as the ratio : systolic blood pressure (SBP)/left ventricular end systolic volume (LVESV).
Results
The study included 93 patients (median age 26 years) with muscular diseases (35% Duchenne muscular dystrophy, 40% Becker muscular dystrophy, 14% gamma sarcoglycanopathy). Non invasive ventilation (NIV) was present in 33 patients (35%) and 54 patients (59%) were wheelchair bound. Almost half of patients (56%) were treated with ACE inhibitors /ARA-II whereas beta-blockers were used in 34 patients (37%). The median LV ejection fraction (LVEF) was 60% [54-65], and the median LV systolic ejection volume was 52 ml [43-74]. The median mitral E/Ea ratio was 6 [5-7.6], while the median TAPSE was 18 mm [16-21]. The median LV performance was 3.3 mmHg/ml [2.36-4.4]. The LV force was associated with NIV (p 0.03), wheelchair use (p 0.03), pulmonary insufficiency status ( r = -0.3, p<0.01 ), LV ejection fraction(r = 0.55, p<0.001), left atrial size ( r= -0.3, p 0.048), LV mass index (r=-0.5, p <0.001) and left ventricular end diastolic diameter (r = -0.8, p <0.001). The LV force is able to predict onset of LV dysfunction (OR 0.6 [0.41-0.91], p = 0.021).
Conclusion
The LV force may serve as a biomarker for identifying patients at risk of left ventricular dysfunction associated with neuromuscular diseases.