Evaluation of cardiac function in asthmatic children by Tissue Doppler Echocardiography

Bronchial asthma is a global health problem with rising prevalence in developing countries. Children with severe asthma can experience cor pulmonale later in life, but little is known about the cardiac changes that might be present earlier in mild or moderate severity of disease. This study aimed to evaluate biventricular function among children suffering from persistent asthma by Tissue Doppler Echocardiography (TDE).

Thirty-five asthmatic children enrolled from Alexandria Children's Hospital between September 2021 to May 2022; they were compared to 35 healthy matched children. Chronic respiratory disease, cardiac disease, or other comorbidities were excluded. The mean age of cases was 8.87 ± 2.03 years with a male/female ratio of 54.3%:45.7%. There were 28.3% mild cases, 45.7% moderate, and 25.7% severe. Conventional echocardiographic variables of cardiac function were normal for both ventricles. The TDE indices of medial mitral annulus (S' velocity and peak E') were significantly reduced (14.55 ± 2.30 and 14.69 ± 2.30) versus controls (15.68 ± 1.96, 15.69 ± 1.76, P; 0.044, P < 0.0045) but with preserved LV function. The lateral tricuspid annulus (S' velocity and peak E') was significantly reduced (11.53 ± 3.24 and 11.56 ± 3.18) versus controls (15.71 ± 0.98, 16.02 ± 1.75, < 0.001*), while E/A and IVRT were significantly increased (1.49 ± 0.06 versus 1.70 ± 0.18 and 102.39 ± 5.37 versus 140.10 ± 34.35, respectively, P < 0.001*) with impaired RV function. Peak expiratory flow rate (PEFR) was negatively correlated with the IVRT of the tricuspid annulus (P = 0.002, r = -0.503*) and to the E'/A' (P = 0.036, r =-0.355*). All TDE variables of lateral tricuspid annulus of severe subgroups were significantly  changed versus moderate or mild subgroups.

Tissue Doppler echocardiography is the recommended modality for early detection of biventricular cardiac dysfunction among children with different levels of asthma severity. Periodic screening is advised through the use of IVRT especially for RV.