Congenital heart disease (CHD) is the most common birth defect, and it is often stated that the incidence of CHD globally is 8 per 1,000 live births (1, 2) with more recent studies finding increases to as high as 9.5 per 1,000 (3). This overall estimate masks significant regional variability. Although varying definitions make quantification difficult, regional studies have found incidences ranging from 1.2 to 17 per 1,000 live births (2). Reported incidences have also increased over time as detection has improved, and it is now estimated that 1.35 million children are born annually with CHD (1). CHD accounted for at least 260,000 deaths in 2017, including 180,000 deaths among infants (4). There is also marked regional inequality in mortality, with mortality rates from CHD correlating closely with country-level socioeconomic indicators. Improving mortality from CHD will be integral to achieving the Sustainable Development Goals (SDGs), including SDG 3.2 to reduce neonatal mortality and SDG 3.4 to reduce premature deaths from non-communicable diseases (5).

Ultimate diagnosis of CHD comes via cardiac imaging, usually echocardiogram. Prenatal diagnosis via fetal echocardiogram is increasingly common in high-resource settings. Detection rates vary greatly—from less than 10% to greater than 80%—depending on setting and cardiac lesion with the lowest detection rates for pulmonary venous anomalies (6). In middle-income countries, access to fetal echocardiography is rare. Even among centers performing congenital heart surgeries, less than half report always having fetal echocardiography available when needed (7).

Screening for critical CHD via pulse oximetry has recently been utilized to capture patients earlier when disease is not prenatally detected. Meta-analyses have found specificity for critical CHD of 99.9%, sensitivity of about 76%, and a false positive rate of 0.14% (8, 9). While many high-income countries now have mandatory screening, challenges in implementation in low- and middle-income countries (LMICs) have been encountered (10, 11). This means many children are identified later by astute clinicians or when symptoms develop. This leads to important delays in treatment that may lead to worse outcomes (12).

Relatively little is known about the epidemiology of CHD in Jordan. There have been four single-center studies to date (13–16). Two studies have reported incidence of CHD with rates ranging from 12.3 per 1,000 live births (13) to 25 per 1,000 (14). Both are substantially higher than internationally reported incidences. Three studies found that ventricular septal defects (VSDs) were the most common abnormality, accounting for more than 40% of CHD (14–16). A fourth study found patent ductus arteriosus (PDA) to be the most common (13). Most children ultimately diagnosed with CHD were referred for evaluation based on murmur or cyanosis (13). CHD is an important factor in both neonatal and childhood mortality in Jordan (17, 18). Fetal echocardiography is available at some referral centers (19). Our goal is to report on the incidence of CHD noted at the largest birthing hospital in Jordan using the largest cohort reported to date in the country.

This is the largest study to date of CHD incidence in Jordan, and we identified a high incidence of CHD at a major tertiary care center. The calculated incidence (24.6 per 1,000 live births with preterm PDA; 17.8 per 1,000 without PDA) is higher than internationally reported averages (1, 2). These high rates are similar to those previously reported in similar studies from Jordan (13, 14). This may reflect the study setting at a tertiary center but may also suggest a higher underlying rate of CHD compared to other settings. Regardless, this high incidence of CHD necessitates ongoing investment in the detection and management of CHD at Al Bashir Hospital and in Jordan more generally. This is further reinforced by high in-hospital death rates, especially among critical CHD such as hypoplastic left heart syndrome.

The reason for this high rate of CHD requires additional investigation. High rates of consanguinity have been identified as a risk factor for CHD in other regional countries (20, 21) and in systematic reviews (22). This has been a proposed etiology for the high rates of CHD (13) and other congenital anomalies (23) in Jordan. It is also possible that environmental, ethnic, or socioeconomic differences account for this increased rate of CHD (1). For example, there is some evidence of varying prevalence of specific lesions across ethnic groups (1, 24). There are also a wide variety of environmental exposures that have been linked with CHD (25). Some authors have observed an increase in PPH during the COVID-19 pandemic (26), which may have played a role in our high rates of PPH as well given that we observed higher rates of PPH in 2021 during the pandemic than in 2019 before it began.

The most commonly identified abnormalities were premature PDA (27.4%), ASD (21.9%), and VSD (17.0%). While PDA was the most commonly identified lesion in one other population-based study from Jordan (13), PDA represented less than 12% of lesions in the three other available studies (14–16). All three of these studies found VSD to be the most common, representing more than 40% of CHD identified. While the high rate of PDA in our study is likely, at least in part, related to the NICU setting and high prevalence of prematurity, this would not account for the relatively high rate of ASD and lower rate of VSD in our population. This likely represents true variability in the populations served by the hospitals conducting these studies. Importantly, the majority of PDAs identified were able to be medically closed with ibuprofen.

Nearly 40% of infants were referred for cardiology evaluation based on a murmur heard on exam, and nearly another 30% were referred based on other congenital abnormalities or maternal risk factors. Less than 1% had a prenatal diagnosis of CHD. This is much lower than the prenatal detection rate when widespread screening is available, which can be near 60% (27, 28). This is likely due to lack of availability of prenatal echocardiography at Al Bashir Hospital. Infants with prenatal diagnoses were either diagnosed in a private institution or on routine obstetric anatomy scans performed by general obstetricians. This is similar to other middle-income countries, where prenatal echocardiography is difficult to access. Among hospitals performing congenital heart surgeries in middle-income countries, fetal echocardiography is reportedly only available and performed about half the time when CHD is suspected (7). Because reduced morbidity and mortality have been described with prenatal diagnosis across various heart lesions (29), this represents a significant potential area for improvement both in Jordan and LMICs more generally. Importantly, some congenital heart disease described in this study cannot be detected prenatally, for example, PDA and ostium secundum ASDs, which are physiologic in utero.

More than 10% of children with abnormal echocardiograms were referred because of failed pulse oximetry screening. This included 125 children with cyanotic heart disease that may not otherwise have been identified before discharge. Pulse oximetry screening was introduced at Al Bashir Hospital during the study period in 2020. Failure to diagnose critical CHD prior to discharge can lead to increased morbidity and mortality (30), and widespread implementation of pulse oximetry screening has been associated with a decrease in mortality (31). Further implementation of screening with pulse oximetry in Jordan may lead to reductions in mortality.

This study identifies a high incidence of CHD at a major tertiary care center in Jordan and describes the most common identified disease. Most children were referred for evaluation based on clinical presentation or examination, and very few were referred based on prenatal diagnosis or pulse oximetry screening. Increased prenatal and perinatal screening for CHD may allow for earlier detection.