Borderline findings in fetal cardiac sonography

How often an isolated cardiac disproportion predicts a coarctation of the aorta? Single center experience and systematic review of the literature

BACKGROUND

Cardiac disproportion is considered as an indirect sign of coarctation of the aorta (CoA). In this review, we have reassessed the positive predictive value (PPV) of such finding for a postnatal confirmation of CoA.

DATA SOURCES

All cases of isolated cardiac disproportion diagnosed in the four-chamber and/or three-vessel/three-vessel and trachea views (right/left sections >1.5) were included. Postnatal cardiac findings were recorded. Additionally, a systematic literature search (PubMed, EMBASE, Cochrane library, and the reference lists of identified articles) regarding the association between antenatally detected cardiac disproportion and postnatal confirmation of CoA was performed. Data from our center were pooled with those derived from the literature.

RESULTS

Ten fetuses with isolated cardiac disproportion were selected from our center and 259 from the literature review. CoA was postnatally confirmed in 101/269 (PPV 38%). PPV of antenatal cardiac findings was significantly higher in earlier gestation (23/27, 85% <26⁺⁰weeks versus 11/39, 28%≥26⁺⁰weeks, p < .001). No significant difference was noticed comparing ventricular disproportion with combined ventricular and great vessels disproportion (86/230 versus 15/39, p  .89).

DISCUSSION

Isolated cardiac disproportion has an overall chance of one in three of heralding a CoA in the neonate. The specificity of these findings is significantly higher in the second trimester.

Echogenic focus in the fetal left ventricular cavity: is it a false tendon?

OBJECTIVE

To draw attention to the left ventricular false tendon which can be misinterpreted as echogenic focus in the fetus.

METHODS

The study group consisted of 9 fetuses out of the 161 who had been misdiagnosed for left ventricular false tendon as echogenic focus by obstetricians. Fetal echocardiography and 2-D color Doppler echocardiography were performed in the pre-postnatal period. The standard fetal echocardiographic views (4,5 chamber views, long axis view of the left ventricle, short axis view of the ventricles and great arteries, three vessels and trachea view, long axis views of the duct and aortic arch) were obtained for each case.

RESULTS

Of the 161 fetuses with echogenic focus in the left ventricle which underwent fetal echocardiography, 9 (5.6%) were diagnosed with false tendons present in the left ventricular cavity with no other cardiovascular anomaly. Six out of 9 patients underwent amniocentesis as follows: for age of over 35 years (two patients), abnormal double-triple screening tests plus echogenic focus (two patients) and soft ultrasonographic markers including echogenic focus (two patients). These fetuses revealed no cardiovascular and other systemic pathology or dysmorphism except for false tendons in the left ventricular cavity.

CONCLUSION

False tendon should be taken into account as differential diagnosis of left ventricular echogenic focus in the fetus. Misinterpretation of false tendon as echogenic focus may cause unnecessary fetal invasive approach and maternal anxiety, especially when it arises with a background of borderline fetal findings and knowledge.

Clinical implication of isolated right dominant heart in the fetus

OBJECTIVE

To evaluate the clinical implication of isolated right dominant heart (RDH) in fetal echocardiography.

STUDY DESIGN

We reviewed the medical records of pregnant women diagnosed with fetal RDH at Asan Medical Center from December 1999 to December 2005. The criteria of RDH were the ratio of right-to-left atrial and ventricular width and the ratio of the diameter of pulmonary artery-to-aorta were greater than 1.5. Fetuses with congenital heart disease, including coarctation of the aorta (CoA), noncardiac anomalies or chromosomal abnormalities were excluded.

RESULTS

RDH was identified in 44 fetuses. Twenty-nine (66%) were confirmed to have normal heart and 15 (34%) had cardiac anomalies by postnatal echocardiogrphy; 11 CoA, 1 interruption of aortic arch, 1 patent ductus arteriosus, and 2 ventricular septal defect. Mean gestational age at presentation with RDH was later in normal fetuses as compared to fetuses with CoA (p < 0.005). Only 26% (4/15) of fetuses presenting with RDH during the second-trimester were found to have normal heart postnatally, compared with 86% (25/29) of those diagnosed in the third-trimester.

CONCLUSION

RDH in the fetus is a risk factor for postnatal CoA particularly when diagnosed in the second-trimester, and should be an indication for neonatal echocardiography.

Fetal intracardiac echogenic foci: current understanding and clinical significance

The detection of fetal intracardiac echogenic foci (ICEF) by ultrasound was first reported in 1987. Despite many investigations, the relationship of ICEF with congenital heart malformations and chromosomal abnormalities remains unclear. This review describes the current understanding of ICEF based on a literature search from 1980 to the present. ICEF are observed in 0.5 to 20 percent of fetuses, with an overall frequency of 5.6 percent. These small, discrete structures near the papillary muscles and chordae tendinae move in synchrony with the intraventricular valves. They likely represent microcalcification of the papillary muscles. ICEF are most commonly seen in the left ventricle and occasionally in the right ventricle or bilaterally. Intra-atrial or diffuse ICEF are rare. In the chromosomally normal fetus, ICEF are not associated with congenital heart defects. The presence of ICEF in fetuses at high risk for chromosomal abnormalities suggests an increased possibility of aneuploidy, especially if other sonographic markers are noted. A similar association is observed with trisomy 21 in particular. The significance of ICEF in fetuses at low risk for aneuploidy is less clear and represents an area for future research.