INDEXED STROKE VOLUME IN CHILDREN WITH VARYING LEFT VENTRICLE EJECTION FRACTION AND ITS CORRELATION WITH VARIOUS CARDIAC FACTORS

OBJECTIVE: To determine the variation in indexed stroke volume (LVSVi) in children with varying left ventricle ejection fraction (LVEF) using cardiac magnetic imaging (CMR) and its correlation with various cardiac factors. METHODS: This observational comparative study was conducted at The Children’s Hospital, Lahore, Pakistan from December 2018 to November 2021. All children below 18 years’ age presenting to hospital for CMR for tissue characterization, having normal vital organs function and no clinical signs of heart failure were included in the study. Relevant clinical data was recorded. CMR was performed using 1.5T Philips Ingenia MRI scanner. The data were analyzed with varying LVEF and correlation of LVSVi with various cardiac factors including indexed left ventricular end diastolic volume (LVEDVi), cardiac output (CO) and heart rate (HR). RESULTS: Out of 175 patients, 170 children up to 18 years old completed the test with mean age 14.3±3.3 years. Mean LVSVi was 42+12 ml/m2 which followed Frank Starling curve except in children with LVEF <36%. Mean LVEDVi was 86±34 ml/m2. LVSVi did not correlate with heart rate or indexed ventricular systolic volumes acting as an independent variable. Minimum LVSVi remained similar all groups as demonstrated through centile distribution. CONCLUSION: Indexed stroke volume is an independent variable in children having normal vital organs function with varying LVEF. It can serve as an independent monitoring parameter for clinical management of children with impaired ejection fraction.