Assessment of Ventricular Functions by Tissue Doppler Echocardiography in Children with Asthma

Abstract

Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E'), annular peak velocity during late diastole (A') (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E'/A' ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E'/A' ratio of the tricuspid annulus (r = -0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.

Relation between Vascular Endothelial Markers and Right Ventricular Function in the Children with Asthma

“…TDI gives the chance of possibility to evaluate both systolic and diastolic functions independently from ventricular geometry and partially from volume load (23). The studies that evaluated TDI measurement in patients with asthma found decreased Em, Am, and Sm waves and shortened ET with concomitant prolongation in IVRT and consequent prolongation in MPI (24). As an indication of diastolic dysfunction, the prolonged IVRT and decreased Em are the signs of delay in RV relaxation.…”

The evaluation of right and left ventricular functions in children with episodic wheezing exposed to environmental tobacco smoke

“…Therefore, it was supposed that in the early period there was a subclinical ventricular diastolic dysfunction especially in the right ventricle in children with asthma and the level of the dysfunction was related to the severity of the lung disease. As in the study of Özdemir et al 18 , it was shown in the study of Sheeded 16 that although clinical and conventional echocardiographic findings were normal in children with asthma, it was correlated with TDE and subclinical RV dysfunction and the severity of the disease. TDE is superior to conventional echocardiography in identifying the subclinical dysfunctions in the early period [16][17][18] .…”

“…As in the study of Özdemir et al 18 , it was shown in the study of Sheeded 16 that although clinical and conventional echocardiographic findings were normal in children with asthma, it was correlated with TDE and subclinical RV dysfunction and the severity of the disease. TDE is superior to conventional echocardiography in identifying the subclinical dysfunctions in the early period [16][17][18] . Therefore, we employed both methods in the present study as in the studies mentioned above, however, no dysfunction was determined by both methods.…”

“…Repeated prolonged exposure to hypoxia with chronic inflammation in bronchial asthma causes stenosis in various oscillatory mediators, being main mechanisms, and cytokines pulmonary vasoconstriction and pulmonary veins [16][17][18][19][20] . As a result, right heart enlargement with ventricular hypertrophy and pulmonary hypertension causing disruptions in cardiac functions develop.…”

“…As a result, right heart enlargement with ventricular hypertrophy and pulmonary hypertension causing disruptions in cardiac functions develop. When the high pressure becomes chronic, RV hypertrophy and dilatation result in systolic and diastolic dysfunction [16][17][18][19][20] . Episodic wheezing is a type of wheezing triggered by the viral upper respiratory infection and generally following an episodic course (>4-6 weeks).…”