A clinical prediction model to estimate the risk for coarctation of the aorta in the presence of a patent ductus arteriosus

Screening for Critical Congenital Heart Defects in Sweden

OBJECTIVES

Early diagnosis of critical congenital heart defects (CCHD) improves survival. We evaluated the relative contributions of prenatal ultrasound, neonatal pulse oximetry screening (POS), and neonatal physical examination (NPE) to the early detection (before discharge) of CCHD in the context of increasing prenatal detection, and POS being a national standard since 2013.

METHODS

Retrospective, nationwide population-based study. All full-term live-born infants with CCHD in Sweden between 2014 and 2019 were included. CCHD was defined as a congenital heart defect requiring surgery or catheter-based intervention or resulting in death within 28 days of birth.

RESULTS

Of 630 infants, 89% were diagnosed before discharge or death, 42% prenatally, 11% from early symptoms, 23% by POS, and 14% from NPE after a negative POS. Four (0.6%) died undiagnosed before discharge and 64/630 (10%) were discharged undiagnosed, with 24/64 being readmitted with circulatory failure and causing 1 preoperative death. Coarctation was the most prevalent CCHD (N = 184), 25% of whom were detected prenatally (12% by POS and 29% by NPE). Two died undiagnosed before discharge and 30% were discharged undiagnosed. Transposition was the second most common defect (N = 150) and 43% were detected prenatally (33% by POS, 1 by NPE) and 2 died undiagnosed before POS. None was discharged undiagnosed.

CONCLUSIONS

POS and NPE remain important for the early detection of CCHD complementing prenatal ultrasound screening. Nevertheless, 1 in 10 with CCHD leaves the hospital without a diagnosis, with coarctation being the predominant lesion. Future research on CCHD screening should have a particular focus on this cardiac defect.

A clinical prediction model to estimate the risk for coarctation of the aorta: From fetal to newborn life

AIM

A prenatal diagnosis of coarctation of the aorta (CoA) is challenging. This study aimed to develop a coarctation probability model incorporating prenatal cardiac sonographic markers to estimate the probability of an antenatal diagnosis of CoA.

METHODS

We reviewed 89 fetuses as an investigation cohort with prenatal suspicion for CoA and categorized them into three subgroups: severe CoA: symptomatic CoA and surgery within the first 3 months; mild CoA: surgery within 4 months to 1 year (29); and false-positive CoA: not requiring surgery (45). Logistic regression was used to create a multiparametric model, and a validation cohort of 86 fetuses with suspected CoA was used to validate the model.

RESULTS

The prediction model had an optimal criterion >0.25 (sensitivity of 97.7%; specificity of 59.1%), and the area under the receiver operator curve was 0.85. The parameters and their cut-off values were as follows: left common carotid artery to left subclavian artery distance/distal transverse arch (LCCA-LSCA)/DT Index >1.77 (sensitivity 62%, specificity 88%, 95% confidence interval [CI]: 0.6-0.8), and z-score of AAo peak Doppler > -1.7 (sensitivity 77%, specificity 56%, 95% CI: 0.6-0.8). The risk assessment demonstrated that fetuses with a model probability >60% should have inpatient observation for a high risk of CoA, whereas fetuses with a model probability <15% should not undergo clinical follow-up.

CONCLUSION

The probability model performs well in predicting CoA outcomes postnatally and can also improve the accuracy of risk assessment. The objectivity of its parameters may allow its implementation in multicenter studies of fetal cardiology.

Incremental value of myocardial deformation in predicting postnatal coarctation of the aorta: establishment of a novel diagnostic model

BACKGROUND

Prenatal detection of coarctation of the aorta (CoA) still suffers from high false-positive and false-negative rates. The objective of this study was to develop a novel model to improve the diagnostic accuracy of fetal CoA.

METHODS

A retrospective study was conducted in 122 fetuses with suspected CoA who also had postnatal follow-ups. Fetuses with confirmed diagnosis of CoA after birth were defined as CoA group, and Non-CoA group were those false-positives. Conventional fetal echocardiographic measurements, including great arterial dimensions and flow characteristics were obtained. Left ventricular (LV) functional parameters were determined using two-dimensional speckle tracking echocardiography. A novel multi-parametric diagnostic model, including gestational age (GA) at diagnosis, aortic isthmus (AOI) Z-score and LV longitudinal strain (LVLS), was developed by univariate and multivariate logistic regression analyses. The model was validated prospectively by a validation cohort of 48 fetuses.

RESULTS

CoA was confirmed in 62/122 (50.8%) cases after birth. Fetuses with postnatal CoA were diagnosed significantly earlier than false-positives (median (interquartile range), 24.5 (23.3-26.4) vs 27.8 (24.5-30.4) weeks; P < .001). The Z-scores of aortic dimensions (aortic valve annulus, ascending aorta, transverse aortic arch and AOI) were significantly smaller (all P < .001), while the Z-scores of pulmonary dimensions (pulmonary valve annulus and main pulmonary artery) were significantly greater (all P < .05), in cases of confirmed CoA than false-positives. Compared with Non-CoA group, CoA group displayed lower LV ejection fraction (P = .005), LV fractional area change (P < .001) and LVLS (P < .001). A multivariate logistic regression model incorporating GA (odds ratio (OR): 0.74, 95% confidence interval (CI): 0.60-0.88; P = .001), AOI Z-score (OR: 0.20, 95% CI: 0.08-0.41; P < .001) and LVLS (OR: 1.79, 95% CI: 1.41-2.42; P < .001) was established to diagnose CoA more accurately (Akaike information criterion: 81.77, C-statistics: 0.945). The performance of this model was confirmed prospectively in the validation cohort.

CONCLUSIONS

In fetuses with suspected CoA, speckle tracking analysis of LVLS may have an incremental value in predicting postnatal CoA. Our diagnostic model, including GA, AOI Z-score and LVLS, may provide a good tool for the stratification of the risk in fetal CoA and contribute to patient-specific perinatal management.

Coarctation of the aorta: Prenatal assessment, postnatal management and neonatal outcomes

Coarctation of the aorta (Coa) is a potentially life threatening diagnosis. It occurs in 0.3 per 1000 live births and accounts for 6-8% of all infants with congenital heart defects. Neonates with severe Coa may be completely asymptomatic at birth, as the ductus arteriosus can provide flow to the lower body. Those who are not diagnosed prenatally may be diagnosed only after constriction of the ductus arteriosus, when they present in cardiogenic shock. This group has a higher risk for mortality and morbidity relative to those diagnosed prenatally. Despite the increasing practice of universal pulse oximetry screening, many cases with significant coarctation of the aorta still go undiagnosed in the newborn period. In this article, we present the pathophysiology, diagnosis, presentation, treatment and outcomes of Coa.

A Fetal Risk Stratification Pathway for Neonatal Aortic Coarctation Reduces Medical Exposure

OBJECTIVE

To test the hypothesis that a fetal stratification pathway will effectively discriminate between infants at different levels of risk for surgical coarctation and reduce unnecessary medicalization.

STUDY DESIGN

We performed a pre-post nonrandomized study in which we prospectively assigned fetuses with prenatal concern for coarctation to 1 of 3 risk categories and implemented a clinical pathway for postnatal management. Postnatal clinical outcomes were compared with those in a historical control group that were not triaged based on the pathway.

RESULTS

The study cohort comprised 109 fetuses, including 57 treated along the fetal coarctation pathway and 52 historical controls. Among mild-risk fetuses, 3% underwent surgical coarctation repair (0% of those without additional heart defects), compared with 27% of moderate-risk and 63% of high-risk fetuses. The combined fetal aortic, mitral, and isthmus z-score best discriminated which infants underwent surgery (area under the curve = 0.78; 95% CI, 0.66-0.91). Compared with historical controls, infants triaged according to the fetal coarctation pathway had fewer delivery location changes (76% vs 55%; P = .025) and less umbilical venous catheter placement (74% vs 51%; P = .046). Trends toward shorter intensive care unit stay, hospital stay, and time to enteral feeding did not reach statistical significance.

CONCLUSIONS

A stratified risk-assignment pathway effectively identifies a group of fetuses with a low rate of surgical coarctation and reduces unnecessary medicalization in infants who do not undergo aortic surgery. Incorporation of novel measurements or imaging techniques may improve the specificity of high-risk criteria.

Analysis of 3-Dimensional Arch Anatomy, Vascular Flow, and Postnatal Outcome in Cases of Suspected Coarctation of the Aorta Using Fetal Cardiac Magnetic Resonance Imaging

BACKGROUND

Identifying fetuses at risk of severe neonatal coarctation of the aorta (CoA) can be lifesaving but is notoriously challenging in clinical practice with a high rate of false positives. Novel fetal 3-dimensional and phase-contrast magnetic resonance imaging (MRI) offers an unprecedented means of assessing the human fetal cardiovascular system before birth. We performed detailed MRI assessment of fetal vascular morphology and flows in a cohort of fetuses with suspected CoA, correlated with the need for postnatal intervention.

METHODS

Women carrying a fetus with suspected CoA on echocardiography were referred for MRI assessment between 26 and 36 weeks of gestation, including high-resolution motion-corrected 3-dimensional volumes of the fetal heart and phase-contrast flow sequences gated with metric optimized gating. The relationship between aortic geometry and vascular flows was then analyzed and compared with postnatal outcome.

RESULTS

Seventy-two patients (51 with suspected fetal CoA and 21 healthy controls) underwent fetal MRI with motion-corrected 3-dimensional vascular reconstructions. Vascular flow measurements from phase-contrast sequences were available in 53 patients. In the CoA group, 25 of 51 (49%) required surgical repair of coarctation after birth; the remaining 26 of 51 (51%) were discharged without neonatal intervention. Reduced blood flow in the fetal ascending aorta and at the aortic isthmus was associated with increasing angulation (P=0.005) and proximal displacement (P=0.006) of the isthmus and was seen in both true positive and false positive cases. A multivariate logistic regression model including aortic flow and isthmal displacement explained 78% of the variation in outcome and correctly predicted the need for intervention in 93% of cases.

CONCLUSIONS

Reduced blood flow though the left heart is associated with important configurational changes at the aortic isthmus in fetal life, predisposing to CoA when the arterial duct closes after birth. Novel fetal MRI techniques may have a role in both understanding and accurately predicting severe neonatal CoA.

Evaluating the severity of aortic coarctation in infants using anatomic features measured on CTA

OBJECTIVES

A machine learning model was developed to evaluate the severity of aortic coarctation (CoA) in infants based on anatomical features measured on CTA.

METHODS

In total, 239 infant patients undergoing both thorax CTA and echocardiography were retrospectively reviewed. The patients were assigned to either mild or severe CoA group based on their pressure gradient on echocardiography. They were further divided into patent ductus arteriosus (PDA) and non-PDA groups. The anatomical features were measured on double-oblique multiplanar reconstructed CTA images. Then, the optimal features were identified by using the Boruta algorithm. Subsequently, the coarctation severity was classified using linear discriminant analysis (LDA). We further investigated the relationship between the anatomical features and re-coarctation using Cox regression.

RESULTS

Four anatomical features showed significant differences between the mild and severe CoA groups, including the smallest aortic cross-sectional area indexed to body surface area (p < 0.001), the narrowest aortic diameter (CoA diameter) indexed to height (p < 0.001), the diameter of the descending aorta at the diaphragmatic level (p < 0.001) and weight (p = 0.005). With these features, accuracy of 88.6% and 90.2%, sensitivity of 65.0% and 72.1%, and specificity of 92.9% and 100% were obtained for classifying the CoA severity in the non-PDA and PDA groups, respectively. Moreover, CoA diameter indexed to weight was associated with the risk of re-coarctation.

CONCLUSIONS

CoA severity can be evaluated by using LDA with anatomical features. When quantifying the severity of CoA and risk of re-coarctation, both anatomical alternations at the CoA site and the growth of the patients need to be considered.

KEY POINTS

• CTA is routinely ordered for infants with coarctation of the aorta; however, whether anatomical variations observed with CTA could be used to assess the severity of CoA remains unknown. • Using the diameter and area of the coarctation site adjusted to body growth as features, the LDA model achieved an accuracy of 88.6% and 90.2% in differentiating between the mild and severe CoA patients in the non-PDA group and PDA group, respectively. • The narrowest aortic diameter (CoA diameter) indexed to weight has a hazard ratio of 10.29 for re-coarctation.

Early Postnatal Echocardiography in Neonates with a Prenatal Suspicion of Coarctation of the Aorta

Coarctation of the aorta (COA) is suspected prenatally when there is ventricular asymmetry, arterial disproportion, and hypoplasia of the aortic arch/isthmus. The presence of fetal shunts creates difficulty in prenatal confirmation of the diagnosis so serial echocardiography after birth is necessary to confirm or refute the diagnosis. The first neonatal echocardiogram in prenatally suspected cases of COA was assessed for prediction of neonatal COA repair (NCOAR). This included morphological assessment, measurement of the aortic arch and calculation of the distal arch index (DAI = distance between left common carotid and left subclavian artery/diameter of the distal arch). NCOAR was undertaken in 23/60 (38%) cases. Transverse arch, aortic isthmus z-score, and DAI had an area under the receiver operator curve of 0.88 (95% CI 0.77-0.98), 0.86 (95% CI 0.75-0.96), and 0.84 (95% CI 0.74-0.95), respectively for the prediction of NCOAR. Using transverse arch z-score threshold < - 3 gave sensitivity 100%, NPV: 100%, specificity 76%; aortic isthmus z-score  < - 3: NPV 92%, specificity 62% and DAI > 1.4: NPV 88%, specificity 78%. The size of the distal aortic arch in infants with a common origin of the innominate artery and left common carotid artery who did not require COA repair was similar to the NCOAR cases (p = 0.22). The early postnatal assessment of the size and morphology of the aortic arch can assist in risk stratification for development of neonatal COA. The branching pattern of the head/neck vessels impacts on the size of the distal aortic arch adding to the complexity of predicting COA based on vessel size.

Fetal Echocardiographic Measures to Improve the Prenatal Diagnosis of Coarctation of the Aorta

The objective of this study is to identify fetal echocardiographic measures that predict postnatal coarctation of the aorta (CoA). A retrospective review of patients from 2013 to 2017 identified 13 cases of prenatal diagnosis of CoA confirmed postnatally and 14 cases of prenatal diagnosis of CoA with normal arches postnatally. There were 30 controls. Measurements were made and indices applied on all available longitudinal fetal echocardiograms for each patient. Linear mixed effects models were used to examine the between-group differences in the trajectories of the measurements. Significant differences were seen in the true CoA group for the following: smaller distal transverse arch diameter to distance between the left common carotid and left subclavian arteries (DT/LCA-LSCA) index (p = 0.04), smaller distal transverse arch diameter (p = 0.005), and longer brachiocephalic to left common carotid artery (LCA) (p = 0.004) and LCA-left subclavian artery (LSCA) distances (p < 0.0001). Additionally, the LCA/DT index trend appears to differentiate false positives from true coarctations (p < 0.03). The fetal echocardiographic DT/LCA-LSCA index, brachiocephalic-LCA distance and LCA-LSCA distance are significant predictors of postnatal coarctation. The LCA/DT index trend over time may differentiate which of those patients with prenatal concern for coarctation are more likely to develop coarctation postnatally. The use of fetal echocardiographic measures may improve prenatal detection and predication of postnatal coarctation.

Diagnosis, imaging and clinical management of aortic coarctation

Coarctation of the aorta (CoA ) is a well-known congenital heart disease (CHD) , which is often associated with several other cardiac and vascular anomalies, such as bicuspid aortic valve (BAV), ventricular septal defect, patent ductus arteriosus and aortic arch hypoplasia. Despite echocardiographic screening, prenatal diagnosis of C o A remains difficult. Most patients with CoA present in infancy with absent, delayed or reduced femoral pulses, a supine arm-leg blood pressure gradient (> 20 mm Hg), or a murmur due to rapid blood flow across the CoA or associated lesions (BAV). Transthoracic echocardiography is the primary imaging modality for suspected CoA. However, cardiac magnetic resonance imaging is the preferred advanced imaging modality for non-invasive diagnosis and follow-up of CoA. Adequate and timely diagnosis of CoA is crucial for good prognosis, as early treatment is associated with lower risks of long-term morbidity and mortality. Numerous surgical and transcatheter treatment strategies have been reported for CoA. Surgical resection is the treatment of choice in neonates, infants and young children. In older children (> 25 kg) and adults, transcatheter treatment is the treatment of choice. In the current era, patients with CoA continue to have a reduced life expectancy and an increased risk of cardiovascular sequelae later in life, despite adequate relief of the aortic stenosis. Intensive and adequate follow-up of the left ventricular function, valvular function, blood pressure and the anatomy of the heart and the aorta are , therefore, critical in the management of CoA. This review provides an overview of the current state-of-the-art clinical diagnosis, diagnostic imaging algori thms, treatment and follow-up of patients with CoA.

Utility of novel fetal echocardiographic morphometric measures of the aortic arch in the diagnosis of neonatal coarctation of the aorta

OBJECTIVES

Prenatal diagnosis of neonatal coarctation of the aorta (CoA) is challenging; there is a high false-positive rate, yet 60-80% are not identified prenatally. We aimed to identify novel fetal echocardiographic measures to improve prenatal identification of CoA.

METHODS

A retrospective review was conducted of subjects seen from 1/2007-1/2014 with prenatal suspicion for CoA and postnatal follow-up. The last fetal echocardiogram prior to delivery was evaluated for right/left ventricular dimensions, ascending (AAo), transverse (TAo), descending aorta (DAo), aortic isthmus (AoI), ductus arteriosus (DA), and main pulmonary artery diameters, and AoI and DA spectral Doppler. Three novel fetal measurements were performed: left common carotid-to-left subclavian artery distance (LCSA), AAo-DAo angle, and TAo-DAo angle. Postnatal data included diagnosis, surgical approach, and timing.

RESULTS

Forty subjects were identified (mean gestational age at fetal echo 32.8 ± 4.2 weeks) with prenatal suspicion for CoA. Comparing subjects with (n = 20) and without CoA (n = 20), significant differences were detected for LCSA, AAo-DAo angle, and TAo-DAo angle (p < 0.0001). An LCSA >4.5 mm (sensitivity 80%,specificity 95%), AAo-DAo angle ≤20.31° (sensitivity 95%,specificity 100%) and TAo-DAo angle ≥96.15°(sensitivity 90%,specificity 100%) identified CoA.

CONCLUSIONS

Fetal LCSA, AAo-DAo angle, and TAo-DAo angles are novel measures that can differentiate between subjects with and without CoA.