ASSESSMENT OF VENTRIICULAR FUNCTIION IIN CHIILDREN WIITH BRONCHIIAL ASTHMA:: A TIISSUE DOPPLER ECHOCARDIIOGRAPHIIC STUDY

Abstract

Bronchial asthma does not only affect the lung but also affects other organs including the heart. Right ventricular systolic and diastolic dysfunctions were found in a considerable percent of asthmatic children even with mild cases. Moreover, Left ventricular dysfunction is usually detected in severe asthmatic cases. However, these cardiac dysfunctions may be reversible especially in acute cases (Zeybek et al., 2007). Tissue Doppler echocardiography (TDE) is a new technique providing quantitative measurement of regional myocardial velocities even when the gray-scale image is suboptimal. Because TDE may detect subclinical RV abnormalities at a stage when conventional echocardiography parameters are still normal, the use of TDE may be superior to that of conventional echocardiography (Correale et al., 2011). The aim of this work was to evaluate the effect of bronchial asthma with different grades of severity and medical control on the ventricular function of the heart using tissue Doppler imaging.. This study was performed at the Pediatric Chest Outpatient Clinic and Pediatric Echocardiographic Lab, Pediatric Department at Ain Shams University. All patients were subjected to the following 1- Full medical history including any other health problems, any history of hospital admissions for chest conditions, family history of bronchial asthma and therapeutic history. 2- Thorough clinical examination including chest and heart examination. 3- Pulmonary function testing using JAEGER, VIASYS Healthcare GmbH Leibinzstrasse 7, Germany to assess Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), FEV1/FVC ratio and Peak Expiratory Flow (PEF). 4- Transthoracic echocardiography (TTE): Routine echocardiography to exclude any previously undiagnosed congenital or acquired heart disease. Conventional echocardiography to assess the cardiac function and the presence of pulmonary hypertension. M mode echocardiography to assess the left ventricle dimension and systolic function. Also Pulsed wave Doppler echocardiography and Tissue Doppler imaging to evaluate myocardial function by using device model (vivid E9 GE vingmed ultrasound A/S N-3191 Horten Norway). In our study, echocardiographic parameters in asthmatic children were nearly similar to echocardiographic parameters measured by m-mode, CWD, PWD and TDI of healthy children. In this study, subgroup analysis showed no significant differences between controlled and uncontrolled asthmatics except for the tricuspid lateral E' velocity which was higher in uncontrolled asthmatics when compared to the controlled. There were statistically significant differences between mild, moderate, severe asthmatics groups as regards to the daily ICS dose and VTI which were higher in severe asthmatics when compared to the mild asthmatics while diastolic PA pressure and the Tei index Septal were low in severe asthmatics. Our results showed also no statistical siginificant differences between male and female asthmatic patients as regards to the ventricular function and dimensions, except for mitral A velocity which was higher in females when compared to males (0.72±0.12 cm/s versus 0.6± 0.13 cm/s), mitral E/A ratio which was low in female asthmatics (i.e. impaired LV diastolic function), mitral septal E' which was higher in males when compared to females and tricuspid A velocity which was higher in females when compared to males. There were statistically significant differences between asthmatic patients with nasal allergy and asthmatics without nasal allergy as regard to LVIDD, TR velocity and RVSP were higher in patients with nasal allergy than asthmatics without nasal allergy. Our results showed also no statistical siginificant differences between the different studied groups and subgroups as regard the mitral and the tricuspid tei index but, there was a statistically significant positive correlation between the Tei index lateral and the age and duration of asthma. In asthmatic group, there was a statistically significant positive correlation between FEV1 / FVC ratio (reduced FEV1/FVC indicates airflow obstruction) and diastolic PA pressure while a negative correlation between FEV1 / FVC ratio and LVIDd & the mitral lateral S velocity were found. Also there was a statistically significant negative correlation between MMEF75/25 and the mitral lateral E' velocity and negative correlation between PEF and the mitral lateral E' & lateral A' velocities.