Pitfalls in Fetal Echocardiography Jung Yun Choi Department

Pitfalls in Fetal Echocardiography Jung Yun Choi Department of Pediatrics Seoul National Univ. Children’s Hospital

Pitfalls of Fetal Echocardiography • Pitfalls due to technical factors • Pitfalls related to interpretation

Pitfalls due to technical factors Structural Image Doppler Spectral Image Color Doppler image

Pitfalls in Structural Image Echo drop-out Artifact : Shadowing Imperfect resolution Slice thickness

Echo drop-out; Shodowing; Artifact

Pitfalls in Color Doppler image Low frame rate Poor range resolution Poor velocity resolution

Range resolution Velocity resolution

Resolution of color Doppler study

Velocity Scale Change

Transducer Frequency Change

Pitfalls in assessing size Normal size Large heart Small heart

Normal size • What is normal ? Mean ± 2 SD • Growth parameters : gestational period, body weight, head circumference, height, etc • Heart parameters : dimension, area, volume

Large Heart • Right or left or both sides • Causes – cardiac malformation – valvular or ventricular dysfunction – secondary to fetal diseases • Effects on fetus; long-term effects

Small Heart • Anatomic definition: diameter / area below - 2 SD ? • Functional definition : too small to be a ventricle • Growth parameters : body weight > gestational age • Any potential of catch up growth ?

How small? • Too small: hardly seen, no potential of growth • Questionable • Not too small: -2 ~ -3 SD, may have a potential

Too Small Heart • Causes : HLHS, HRHS • How to assess : PFO, ductus, coronary fistula • Counsel : single ventricle and Fontan

Not Too Small • Causes: unknown, COA, AS, MS, PS etc • How to assess: complete study on heart / vessel • Counsel : cautious optimism

An example of LV being ‘Not Too Small’

An example of LV being ‘Not Too Small’

Pitfall in Natural History • Newly diagnosed in the 3 rd trimester • Cardiac malformations become worse • Cardiac defects / diseases become better

Newly diagnosed in the 3 rd trimester • Cardiac malformation • Cardiomyopathy • Cardiac tumor • Secondary cardiac disease

Natural History May get worse May get better May stay the same

Pitfalls in Arrhythmia • Technical pitfalls: difficult to obtain signal • Interpretation: requires thorough knowledge • Common mistake – transient bradycardia – intermittent premature contraction

M-mode is difficult to obtain

Frequently Poor Tracing: difficult to identify wall motion ← Ventricular wall ← Mitral valve ← Atrial wall Occasionally Good Tracing : Atrial wall contraction precedes mitral valve closure and ventricular contraction ← Ventricular wall ← Mitral valve ← Atrial wall

Premature Atrial Contraction

Brief bradycardia is common

Intermittent premature contraction is frequent