Tissue Doppler Echocardiography As A Predictor Of Early Subclinical Right Ventricular Diastolic Dysfunction In Asthmatic Children.

Objectives: To assess the effect of asthma in children on systolic and diastolic functions of the heart, and to explore the relationship between the two. Method: The case-controlstudy was conducted at Kafrelsheikh University Hospital, Egypt, from September 2019 to May 2022, and comprised asthmatic children of either gender aged 5-15 years and healthy controls matched for age and gender. The participants were subjected to detailed history, complete examination, spirometry evaluation and conventional and tissue Doppler echocardiography. Myocardial performance index was calculated and compared. Data was analysed using SPSS 22. RESULTS: Of the 120 subjects, 60(50%) were cases; 33(55%) boys and 27(45%) girls with mean age 9.4±2.9 years(range: 5-15 years). The remaining 60(50%)subjects were controls; 34(56.6%) boys and 26(43.3%) girls with mean age 9.7±2.9 years (range: 5-15 years). Left ventricular dimensions, estimated pulmonary artery pressure, and right ventricular dimensions showed no significant inter-group differences (p>0.05), but right ventricular end diastolic diameter was significantly higher in the cases than the controls (p=0.046). Tissue Doppler showed that lateral annular peak Ê, Â, isovolumetric relaxation time and myocardial performance index values were significantly different between the groups (p<0.05). CONCLUSIONS: Tissue Doppler echocardiography could detectsubtle right ventricular diastolic dysfunction in asthmatic children even with no clinical symptoms and normal findings on conventional echocardiography.

Improved catheter tracking during cardiovascular magnetic resonance-guided cardiac catheterization using overlay visualization.

INTRODUCTION: Cardiovascular magnetic resonance (CMR)-guided cardiac catheterization is becoming more widespread due to the ability to acquire both functional CMR measurements and diagnostic catheterization data without exposing patients to ionizing radiation. However, the real-time imaging sequences used for catheter guidance during these procedures are limited in resolution and the anatomical detail they can provide. In this study, we propose a passive catheter tracking approach which simultaneously improves catheter tracking and visualization of the anatomy. METHODS: 60 patients with congenital heart disease underwent CMR-guided cardiac catheterization on a 1.5T CMR scanner (Ingenia, Philips Healthcare, Best the Netherlands) using the Philips iSuite system. The proposed T1-overlay technique uses a commercially available heavily T1-weighted sequence to image the catheter, and overlays it on a high-resolution 3D dataset within iSuite in real-time. Suppressed tissue in the real-time images enables the use of a thick imaging slab to assist in tracking of the catheter. Improvement in catheter visualization time was compared between T1-overlay and the conventional invasive CMR (iCMR) balanced steady state free precession (bSSFP) sequence. This technique also enabled selective angiography visualization for real-time evaluation of blood flow dynamics (such as pulmonary transit time), similar to direct contrast injection under standard fluoroscopy. Estimates of pulmonary transit time using iCMR were validated using x-ray fluoroscopy in 16 patients. RESULTS: The T1-overlay approach significantly increased the time that the catheter tip was kept in view by the technologist compared to the bSSFP sequence conventionally used for iCMR. The resulting images received higher ratings for blood/balloon contrast, anatomy visualization, and overall suitability for iCMR guidance by three cardiologists. iCMR selective angiography using T1-overlay also provided accurate estimates of pulmonary transit time that agreed well with x-ray fluoroscopy. CONCLUSION: We demonstrate a new passive catheter tracking technique using the iSuite platform that improves visualization of the catheter and cardiac anatomy. These improvements significantly increase the time that the catheter tip is seen throughout the procedure. We also demonstrate the feasibility of iCMR selective angiography for the measurement of pulmonary transit time.