NON INVASIVEASSESSMENTOF MYOCARDIAL PERFORMANCE IN PRETERMINFANTS
|Full paper||Not Available|
The effects oftransitionfromfetal to postnatal circulation on left ven tricularfunction in human premature infants are largely unfcnoiun. This study was conducted to determine the resting LV contractile state in pre mature infants by studying, non invasively, the relation between wall stress and velocity of circumferentialfiber shortening and also to study the rightventricularJunctionandmeanpulmonary arterypressure inpre matures. This study included 52 premature infants (29males and 23 fe males) with a gestational age of 26 - 36 weeks and mean of 34.11 weeks. Their age was 4.2+1.5 days. Infants with cardiovascular or any major complicationswere excluded. Another 50 healthyfull termbabies (29 males and 21 females) with a mean age of3.18+1.52 days were also studied. Full echo Doppler study was performedfor each infant to calculate left ventricular ejectionfraction (LVEF), left ventricularfractional shortening (LVFS), left ventricular veloci ty ofcircumferentialfiber shortening(LWCFc), left ventricularwall stress, meanpulmonary artery pressure, right ventricular ejectionfraction(RVEF) using Simpson's rule. Curves relating VCFc towall stress were construct edforpremature andfull terminfants. AilM-Mode echocardiographic di mensions were statistically less inpremature babies while LVFS, LVEF, VCFc, LV weft stress showed no significant difference between both groups. In both groups there were significant negative correlation be tween LVwall stress and VCFc however the curvefor premature infants was steeper and with higher y intercept.