Congenital heart disease accounts for approximately 0.4 to 1.3% of all live births and is a leading cause of perinatal mortality. Interestingly, congenital cardiac defects is the most common form of human malformation (Lantin-Hermoso, 2005). Fetal echocardiology is without question the most prominent method for identifying congenital defects. Prenatal ultrasound screening, routinely offered between 18 and 20 weeks of pregnancy typically identifies cardiac anomalies, which results in a comprehensive cardiac examination by a fetal echocardiographer (Zhang, Cai, Ren, Guo, & Zhang et al., 2016).
Not all heart defects require surgical intervention or are even realized in the first few decades of life. If the defect is mild or not hemodynamically significant, they can easily go unidentified. Small patent formed ovales, mild pulmonary stenosis, clinically silent patent ductus arteriosus, functionally normal bicuspid aortic valves and small ventricular septal defects (Lantin-Hermoso, 2005, p 513). Other anomalies may be fairly insignificant so that they are well-tolerated into adulthood without intervention, but they do typically become symptomatic with time, requiring intervention (Lantin-Hermoso, 2005).
Tetralogy of Fallot
Tetralogy of Fallot (TOF) is one of the more common congenital heart diseases, affecting approximately 5 of every 10,000 live births or 10% of all congenital cardiac malformations. Surgical correction has significantly improved survival of these patients, without which only 30% survive the first decade and fewer than 5% through the fourth. Chromosomal anomalies have been identified as a contributing factor, as well as maternal diabetes, exposure to virus, and various teratogens (Swamy, Bharadwaj, Varadarajan, & Pai, 2014).
Four components are essential to tetralogy of fallot: a perimembranous ventricular septal defect (VSD), right ventricular outflow tract obstruction (RVOTO), an overriding aortic root, and a hypertrophied right ventricle (Swamy, Bharadwaj, Varadarajan, & Pai, 2014, p 40). This anomaly occurs during the fourth and fifth week of embryonic development with variable severity. A variety of congenital anomalies are associated with tetralogy as it ultimately is associated with either catastrophic genetic mutations or significant teratogen assault. The severity of the co-morbid conditions determines the long-term outcomes post-surgery (Swamy, Bharadwaj, Varadarajan, & Pai, 2014).
Prenatal screening typically identifies tetralogy of fallot and typically pediatric cardiology is consulted at this time. These neonates are expected to do well following birth, as there is typically little restriction in perfusion with equal pressures in both ventricles. Surgical intervention is anticipated within the first year of life, as symptoms demand. Most often parents will share the child is experiencing bluish discoloration around the lips, although cardiology will continue to evaluate the heart’s ability to meet the needs of the growing body. If the anomaly is not identified in the prenatal or early neonatal period, cyanosis in early infancy or in the first few years of life typically lead to diagnosis. Pulmonary stenosis is progressive, even if mild initially. Surgery will eventually be required and depending on severity (Lantin-Hermoso, 2005; Swamy, Bharadwaj, Varadarajan, & Pai, 2014).
Closure of the ventricular septal defect and relieving the RVOT obstruction is the major objective. When adults with tetralogy of fallot are being assessed, the echocardiography is evaluating residual VSD, pulmonary regurgitation with associated RV dilation, infundibular stenosis, aortic root dilation, residual uncorrected anomalies, hypoplastic pulmonary annulus, pulmonary artery or its branches, or pulmonary artery branch stenosis (Swamy, Bharadwaj, Varadarajan, & Pai, 2014, p 44). Expert ultrasonographers are vital for continued assessment, as well as echocardiography. Cardiac MRI is currently the preferred method for measuring pulmonary regurgitation, providing information on the pulmonary and systemic blood flow through the VSD, evaluating the pulmonary arteries, and calculating the size and function of the ventricles (Swamy, Bharadwaj, Varadarajan, & Pai, 2014).
Major causes of death in those who do not undergo surgery include hypoxic spells, cerebrovascular accidents and brain abscesses. However, early reparative surgery drastically decreases the mortality rate of these patients. All adults who have had, or even have not had reparative surgery require routine surveillance via echocardiograms. Pulmonary regurgitation is the most common postoperative sequelae and is an important determinant of late morbidity and mortality. Typically while this regurgitation may be tolerated early on, over time this will lead to exercise intolerance, heart failure, tachyarrhythmia, and late sudden death (Swamy, Bharadwaj, Varadarajan, & Pai, 2014).
Bicuspid Aortic Valve
Bicuspid aortic value is not often discussed in texts detailing congenital heart defects, as it is not traditionally-defined as heart disease. Studies are often old or too narrow to be clinically applicable to most. It is an anomaly however, that clinicians need be acquainted. The congenital bicuspid valve is simple an arctic valve with two leaflets as opposed to the typical three (Tripathi, Wang, & Jerrell, 2018).
Approximately 1-2% of all pediatric cardiac anomalies are of this variety. The average age of diagnosis is four years of age, but because it can entirely silent, some go undiagnosed for several decades. The majority of patients have relatively normal valve function until late adulthood, when they begin to have stenosis or regurgitation with increasing age. However, those that have other cardiac complications, such as coarctation of the aorta or ventricular septal defect are more susceptible to complications (Tripathi, Wang, & Jerrell, 2018).
Children may present with exercise intolerance or fatigue even into adulthood. More infrequently, patients will complain of chest pain with exercise, dizziness, and syncope during the first decade of life. A systolic ejection click may be auscultated on clinical exam, which most often is the first or only sign leading to diagnosis. An echocardiogram would confirm diagnosis, although it is sometimes picked up incidentally when the echocardiogram is ordered for cardiac surveillance for another indication (Tripathi, Wang, & Jerrell, 2018).
Bicuspid valves has been identified as the root cause of up to 85% of all pediatric aortic stenosis cases, and is a risk factor for infective endocarditis and acute thoracic aortic emergencies. It is also a common risk factor for valve-related complications. Sadly, even when these children, or any child with an congenital cardiac anomaly, survive into adulthood, they are at increased risk for sudden death. (Tripathi, Wang, & Jerrell, 2018, p 120).
Surgery is the preferred therapy when coexisting pathology is present; however, most do not require surgery. This may include dilation, aneurysm, coarctation, or other structural anomalies such as ventricular septal defect. Outcomes are generally excellent and the progression towards valve dysfunction or aortic dilation is quite slow, except for those with comorbid hypertension (Tripathi, Wang, & Jerrell, 2018, p 120).
Coarctation of the Aorta
Coarctation of the aorta is a distinct narrowing of the aorta which causes complications such as hypertension, heart failure, intracranial bleeding, aortic rupture, myocardial infarction and endocarditis. It is the underlying cause of more than 1/3rd of all infantile hypertension cases (Raj & Greydanus, 2017). Coarctation is a common lesion among those with congenital cardiac anomalies with significant risk for mortality and morbidity. Surgery, or stent placement, is typically required with the main goal being removal of stenosis. The surgical technique is therefore, determined based on the location and extensiveness of the coarcted segment (Kaya, Colak, Becit, Ceviz, & Kocak, 2018).
Depending on the severity at birth, this anomaly may go unnoticed initially or even years. Less severe restrictions may result in exercise intolerance, headaches, shortness of breath, cold feet, or leg pain after exercise. There may be a discrepancy between blood pressure in the upper extremities compared to those in the lower. A delay in pulse from the radius to the femoral artery is a significant clinical indicator of coarctation (Raj & Greydanus, 2017).
Primary Care Role
No matter the cardiac defect, the primary care provider can monitor the child through height and weight measurements with the understanding that a lag in growth indicates the child’s heart is not meeting physical demands. In a young child, this may present as failure-to-thrive. Developmental, cognitive, language, social, and neurological delays may be a reality as the child faces significant hurdles daily. These children may require referrals for speech, occupational, or nutritional therapy (Lantin-Hermoso, 2005).
The heart and respiratory rate, blood pressure, and presence of cyanosis should be carefully evaluated as well. All laboratory tests should be obtained only with clinical indication. Those with cyanosis may require a complete blood count to identify polycythemia or iron deficiency anemia. Those on diuretic therapy may benefit from periodic serum electrolyte evaluation. Patients with mechanical prosthetic valves require regular INR monitoring to prevent hemorrhagic events and thromboembolism. Testing is best ordered in collaboration with the pediatric cardiologist to avoid repetition (Lantin-Hermoso, 2005, p 516).
The primary care provider should be cognizant of otherwise insidious or benign illness that may prove catastrophic for the child with a cardiac anomaly. They often have minimal cardiac reserve so a gastrointestinal upset may deplete there intravascular volume. The Hemophilius influenza b (Hib) series is recommended, as well as the pneumococcal vaccine. It is the role of the primary care provider to share in the healthcare management, with the pediatric cardiologist, of the child as the cardiologist will utilize expertise specific to the cardiac anomaly while the primary care provider will provide ongoing evaluation of the entire child, coordinating care management throughout the specialties (Lantin-Hermoso, 2005).
It is thought that more adults are now living with congenital heart disease than children due to the advances in healthcare delivery. For this reason, the primary care provider must consider best management practices for caring for these patients into their adult lives. Control of lipid levels, serum glucose concentrations, and other risk factors are a growing priority. Encouraging physical activity to the best of the child’s capability will optimize cardiac health into adulthood. Overall weight may be reduced and physical activity can influence their lipid profile. Feeding habits early in life also play a role, such that promoting breastfeeding must be a priority for the clinician (Ghaderian, Emami-Moghadam, Samir, Zadeh, & Saadi, 2013).
References
Ghaderian, M., Emami-Moghadam, A. R., Samir, M. A., Zadeh, M. A., & Saadi, A. H. (2013). Lipid and glucose serum levels in children with congenital heart disease. The Journal of Tehran University Heart Center, 9(1), 20-66.
Kaya, U., Colak, A., Becit, N., Ceviz, M., & Kocak, H. (2018). Surgical management of aortic coarctation from infant to adult. Eurasian Journal of Medicine, 50, 14-18. DOI 10.5152/eurasianjmed.2017.17273
Lantin-Hermoso, M. R. (2005). Pediatric cardiology for the primary care pediatrician. Indian Journal of Pediatrics, 72, 513-518.
Raj, V. & Greydanus, D. E. (2017). A review of hypertension in children. International Journal of Child & Adolescent Health, 10(4), 439-453.
Swamy, P., Bharadwaj, A., Varadarajan, P., & Pai, R. (2014). Echocardiographic evaluation of tetralogy of fallot. Echocardiography. DOI: 10.1111/echo.12437
Tripathi, A., Wang, Y., & Jerrell, J. M. (2018). Population-based treated prevalence, risk factors, and outcomes of bicuspid aortic valve in a pediatric Medicaid cohort. Annuals of Pediatric Cardiology. Retrieved from http://0-content.ebscohost.com.oak.indwes.edu/ContentServer.asp? T=P&P=AN&K=129488383&S=R&D=a9h&EbscoContent=dGJyMNHr7ESep644yOvsOLCm r1Cep7VSsay4SLOWxWXS&ContentCustomer=dGJyMPGutk%2B0qLRPuePfgeyx44Dt6fIA
Zhang, Y., Cai, A. L., Ren, W. D., Guo, Y. J., Zhang, D. Y., Sun, W., Wang, Y., Wang, L., Qin, Y., & Huang, L. P. (2016). Identification of fetal cardiac anatomy and hemodynamics: a novel enhanced screening protocol. BMC Pregnancy and Childbirth,16(145). DOI 10.1186/s12884-016-0933-9
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