History
Manifestations of coronary artery disease (CAD) reflect myocardial ischemia and are recognized clinically as the following:
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Myocardial dysfunction
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Angina
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Dysrhythmia
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Infarction [10]
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Death
Pediatric CAD usually presents in infancy as cardiogenic shock or later in childhood or adolescence as an activity-related phenomenon, syncope, or chest pain.
In infants, angina may be recognized by the following symptoms:
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Irritability
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Diaphoresis
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Gray or poor color in association with symptoms
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Poor output or congestive heart failure (CHF)
Most infants present at age 2-3 months with the following symptoms:
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Poor feeding
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Dyspnea
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Wheezing
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Periods of pallor
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Failure to thrive
In the older child or adolescent, anginal chest pain or syncope associated with activity is suggestive of CAD.
Unfortunately, in a significant number of patients, symptoms may not be evident before a sudden catastrophic, presumably dysrhythmic, event. Ventricular dysrhythmias are usually the terminal event in these circumstances.
Sudden death is most often associated with activity. It is frequently observed in association with anomalous origin of the left coronary artery (LCA) from the right sinus of Valsalva and coursing between the two great arteries. In this circumstance, the coronary artery often has an oblique origin, slitlike ostia, and intramural and interarterial course.
Coronary ischemia is felt to arise from disturbed kinetics from oblique origin, ostial stenosis, compression of intramural course, loss of reservoir capacity, and increased myocardial oxygen demands associated with exercise.
Sudden death is less commonly seen in association with anomalous origin of the right coronary artery (RCA) from the left sinus of Valsalva. It has also been reported in association with ostial stenosis, atresia, or hypoplasia.
Physical Examination
In infancy with coronary ischemia, patients present with signs of CHF and low output. The apex beat is diffuse with a palpable or audible third heart sound (S3) gallop. Heart sounds are often reduced in intensity with a holosystolic murmur of mitral valve insufficiency audible at the apex. In the older child, physical examination findings vary from entirely normal (most often) to findings of cardiogenic shock caused by myocardial infarction (rare).
Older patients with a coronary arterial fistula may present with signs of CHF, a continuous murmur, and, rarely, endocarditis.
Causes
Associated syndromes
Coronary anomalies may be commonly associated with other congenital cardiac malformations, most notably, transposition of the great arteries, tetralogy of Fallot malformation, and different forms of pulmonary atresia. Each of these topics is addressed specifically in other chapters.
Williams syndrome
Patients with Williams syndrome (elfin facies, infantile hypercalcemia, hypoplastic teeth) may have coronary ostial narrowing as a component of supravalvar aortic stenosis characteristic of this disease. Patients with aortic valve disease commonly have variants in ostial origin. Those with varied forms of left ventricular outflow tract obstruction are at greater risk for increasing myocardial oxygen demand with limited ability to augment oxygen supply, placing them at increased risk for myocardial underperfusion.
D-transposition of the great arteries [11]
Coronary arteries in transposition of the great arteries normally arise from facing sinuses of Valsalva. Variation in coronary arterial patterning is frequent, and distribution of coronary pattern, as described by Sim et al, is presented in the image below. [12]
Thirteen patterns of origin and proximal epicardial course of coronary arteries in 255 hearts with complete transposition of the great arteries. LAD = left anterior descending coronary artery; LCA = left coronary artery; LCx = left circumflex coronary artery; RCA = right coronary artery. (Image courtesy of Excerpta Medica, Inc).
Correct identification of the origin and course of coronary vasculature is important for patients undergoing Jatene arterial switch procedure. The presence of an intramural coronary artery course in this condition may complicate arterial switch operation.
According to Pasquini, this anomaly may be suggested on echocardiographic study by the eccentric origin of the coronary ostia arising away from the middle third of the aortic sinus and coursing within the aortic wall (see Transposition of the Great Arteries). [13]
Tetralogy of Fallot [11]
Operative repair of pulmonary outflow obstruction often involves patching of the right ventricular outflow tract and resection of the obstructing right ventricular muscle. [14]
An estimated 2-9% of patients with tetralogy of Fallot have coronary arterial anomalies, possibly affecting timing or approach to operative repair. The most common anomaly is origin of the left anterior descending (LAD) coronary artery from the RCA, which then courses across the pulmonary outflow tract. This is estimated to occur in approximately 4% of patients (see the image below.)
Thirteen patterns of origin and proximal epicardial course of coronary arteries in 255 hearts with complete transposition of the great arteries. LAD = left anterior descending coronary artery; LCA = left coronary artery; LCx = left circumflex coronary artery; RCA = right coronary artery. (Image courtesy of Excerpta Medica, Inc).
Frequently, the conus branch of the RCA is large and supplies a significant portion of right ventricular infundibular muscle. Surgical techniques to avoid transection include limited incisions, varied tunneling techniques, and perhaps conduit placement. Cardiologists must predefine these abnormalities by noninvasive or invasive study (see Tetralogy of Fallot with Absent Pulmonary Valve, Tetralogy of Fallot with Pulmonary Atresia).
Pulmonary atresia with intact ventricular septum [11]
In this condition, absence of effective egress of blood from the cavity of the right ventricle may preserve primitive embryonic sinusoidal connections to coronary vasculature, resulting in the filling of the connections from the right heart in systole and filling from the aorta in diastole.
These abnormal right ventricular coronary sinusoidal connections can be recognized echocardiographically and angiographically. [15] The coronary vessel most often affected is the RCA, but the LAD system or, less frequently, the distal extent of the circumflex (Cx) coronary artery may also be affected. In addition, 70% of these coronary arteries may demonstrate severe intimal thickening, occlusion, or interruption.
In most cases, endocardial fibroelastosis, myocardial fibrosis, and acute myocardial infarction are observed. Optimal coronary arteriography often is required to delineate the extent of these abnormalities. Medical and surgical management strategies are varied and often ineffective (see Pulmonary Atresia with Intact Ventricular Septum).
Hypoplastic left heart syndrome and Shone complex
Clinically important anomalies of the left coronary system do occur in patients with left heart obstructive disease and can affect surgical approach and outcome, highlighting the importance of routinely attempting to identify coronary anatomy in pediatric patients with congenital heart disease. [11, 16]
Congenitally corrected transposition of the great arteries (atrioventricular and ventriculoarterial discordance
Congenitally corrected transposition of the great arteries (atrioventricular and ventriculoarterial discordance has much less variability of coronary anatomy than d-TGA. Most patients have so-called typical arrangement of the coronary origins; however, surgically important variations exist. [11]
Other forms of congenital heart disease
Other forms of congenital heart disease associated with coronary artery anomalies include truncus arteriosus, double outlet right ventricle, and bicuspid aortic valve. [11]
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Incidence of coronary artery abnormalities detected in 1,950 selective coronary angiograms performed in adult patients with suspected coronary arterial obstructive disease and otherwise anatomically normal hearts.
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Normal anatomy of coronary arteries, viewed from above with the atria removed. A = aortic valve; P = pulmonary valve; T = tricuspid valve; M = mitral valve; RCA = right coronary artery; AM = acute marginal branch of the right coronary artery; CB = conus branch of the right coronary artery; PD = posterior descending branch; AVN = atrioventricular nodal branch; Circ = circumflex coronary artery; OM = obtuse marginal branches of circumflex coronary artery; LAD = left anterior descending coronary artery; Diag = diagonal branches of the left anterior descending coronary artery; Inter = intermedius branch of the left coronary artery.
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Thirteen patterns of origin and proximal epicardial course of coronary arteries in 255 hearts with complete transposition of the great arteries. LAD = left anterior descending coronary artery; LCA = left coronary artery; LCx = left circumflex coronary artery; RCA = right coronary artery. (Image courtesy of Excerpta Medica, Inc).
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MRI of anomalous right coronary artery (RCA = black arrow) arising from the left sinus of Valsalva and coursing interatrially between the aorta (AO) and the pulmonary artery (PA). Note the oblique origin and the intramural course within the aortic wall, all factors compromising coronary blood flow.
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Three-dimensional volume rendering from multidetector CT imaging of a large right coronary artery aneurysm (arrow). Subtraction of the myocardium in B shows the fistula draining to the coronary sinus and then into the right atrium. (Reproduced from Manghat NE, Morgan-Hughes GJ, Marshall AJ, Roobottom CA: Multidetector row computed tomography: imaging congenital coronary artery anomalies in adults. Heart 2005 Dec; 91(12): 1515-22).
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Selective right coronary arterial injection in an 8-month-old female with tetralogy of Fallot malformation. Study demonstrates left anterior descending coronary artery (LAD) arising early from the right coronary artery (RCA) and coursing across the right ventricular outflow tract. Left anterior oblique projection.
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Operative repair of anomalous left coronary artery (LCA) from the right sinus of Valsalva. The slitlike anomalous origin of the left coronary artery from the right aortic sinus of Valsalva is demonstrated, as is the intramural course of the coronary artery. (B) The intramural course of the artery is unroofed, placing the functional ostium in the left sinus. (C) Tacking sutures are used to secure the intima of the new coronary ostium and to reinforce the adjacent commissure of the aortic valve. (Reproduced from Jaquiss RD, Tweddell JS, Litwin SB: Surgical therapy for sudden cardiac death in children. Pediatr Clin North Am 2004 Oct; 51(5): 1389-400).
