Journal of The Indian Academy of Echocardiography & Cardiovascular Imaging

FOCUS ISSUE - CONGENITAL HEART DISEASE
Year
: 2020  |  Volume : 4  |  Issue : 3  |  Page : 362--369

Coronary Artery Anomalies: Echocardiographic Evaluation


Aditi Gupta1, Munesh Tomar2,  
1 Department of Pediatrics, Lincoln Medical Center, New York, NY, USA
2 Department of Pediatrics, LLRM Medical College, Meerut, Uttar Pradesh, India

Correspondence Address:
Dr. Munesh Tomar
Department of Pediatrics, LLRM Medical College, Garh Road, Jai Bhim Nagar, Meerut - 250 002, Uttar Pradesh
India

Abstract

Congenital coronary artery anomalies occur either in isolation or in association with other congenital heart disease. With the advent of multimodality imaging, the number of incidentally detected anomalies of coronary origin has risen over the last decade. The clinical presentation of these anomalies can range from being asymptomatic to serious morbidity and mortality, including sudden cardiac death in children and adolescents. We review the most common coronary anomalies and various echocardiographic views used to image the coronary arteries origin, size, and flow.



How to cite this article:
Gupta A, Tomar M. Coronary Artery Anomalies: Echocardiographic Evaluation.J Indian Acad Echocardiogr Cardiovasc Imaging 2020;4:362-369


How to cite this URL:
Gupta A, Tomar M. Coronary Artery Anomalies: Echocardiographic Evaluation. J Indian Acad Echocardiogr Cardiovasc Imaging [serial online] 2020 [cited 2021 Mar 1 ];4:362-369
Available from: https://www.jiaecho.org/text.asp?2020/4/3/362/303946


Full Text

 Echocardiography: General Principles of Coronary Imaging



Imaging of the coronary arteries in children is best performed with the use of the highest frequency transducer relative to patient's size to provide superior gray-scale resolution (i.e., 8, 10, or 12 MHz).[1] However, attempts should be made to use lower frequency transducers to demonstrate color Doppler flow as higher frequency transducers may not be sensitive enough for color Doppler imaging of coronary arteriesCoronary vessel has the best resolution when the vessel is perpendicular to the beam in two-dimensional imaging,[2] while color Doppler measurement of flow velocities is most accurate when the beam is parallel to flow[1]Coronaries are best imaged from a parasternal short-axis view, in which both CA origins can be visualized [Figure 1]a, [Figure 1]b and [Figure 2]a, [Figure 2]b. When the aortic sinus is imagined as clock, the left main coronary artery (LCA) origin normally arises at approximately 4 o'clock, and the right coronary artery (RCA) arises at approximately 11 o'clock. Clockwise rotation of the transducer in the parasternal short-axis view allows for imaging of the LCA as it bifurcates into the left anterior descending branch (LAD), which courses along the anterior interventricular groove, and the left circumflex branch (LCx), which courses in the left anterior atrioventricular groove. In contrast, counterclockwise transducer rotation facilitates imaging of the RCAFrame rate and Nyquist limit are important factors in imaging coronary arteries. Since the heart rates in children are typically higher than in adults and coronary vessels are small, superficial structures, reducing depth and sector size helps in improving frame rate.[2],[3] For color imaging, a Nyquist limit of 30 cm/s may be used as the starting point with gradually lowering the limit until color flow in coronary arteries is detected [Figure 1]b and [Figure 2]b[4]An electrocardiographic tracing is necessary to correctly assess CA blood flow. While RCA flow occurs in both diastole and systole.[5],[6] Left CA flow occurs predominantly in diastole[7]When coronary arteries are not adequately visualized with echocardiography, other imaging modalities (i.e., computed tomography, magnetic resonance imaging, or cardiac catheterization) may need to be considered.{Figure 1}{Figure 2}

 Classification of Coronary Anomalies Observed in Human Hearts



Following classification has been used to define coronary anomalies:[8],[9]

Anomalous pulmonary origin of coronaries

Anomalous origin of left CA from the pulmonary arteryLAD artery alone from the pulmonary arteryLCx artery from the pulmonary arteryAnomalous origin of right CA from the pulmonary artery.

Anomalous aortic origin of coronaries

Location of coronary ostium within proper aortic sinus of Valsalva but tangential origin (for each artery): high, low, commissuralAnomalous location of coronary ostium outside normal “coronary” aortic sinusesOrigin from noncoronary sinusOrigin from opposite, facing “coronary” sinus.LCA arising from right anterior sinus with anomalous courseRetroaortic or posteriorInterarterialSubaortic or septalPrepulmonary or anterior.RCA arising from left posterior sinus with anomalous course similar to the previous situationIsolated LAD artery or Isolated LCx from the right anterior sinusSingle coronary artery (from left or right sinus)Anomalies of coronary branchingAbsent LCA, separate LAD artery, LCx originLCx from RCADual LAD artery, posterior descending artery.

Coronary arteriovenous fistula—draining to superior vena cava, coronary sinus, right atrium, right ventricle, pulmonary artery, pulmonary vein, left atrium, left ventricle.Kawasaki disease.

 Anomalous Origin of Left Coronary Artery from Pulmonary Artery



Anomalous origin of the LCA from the PA (ALCAPA), also called Bland-White-Garland Syndrome is a rare CA anomaly, with a reported incidence of 1 in 300,000 children.[10]

This CA anomaly has a high mortality rate of 90% in infants if they do not undergo surgical repair in the 1st year of life.[11] The heart develops normally in fetal life and after birth as pressure in the pulmonary trunk falls, the coronary artery pressure falls and the perfusion of the left ventricle becomes inadequate, which leads to decrease of left ventricular function and increase of left ventricular end-diastolic pressure compromising the perfusion further leading to myocardial ischemia.

The typical time of presentation depends on the extent of collateralization from RCA to LV myocardium. Children with inadequate collateralization present in the first few weeks of life related to the fall in pulmonary vascular resistance with signs of myocardial ischemia, which present clinically as tachypnea, pallor, feeding intolerance, and failure to thrive. Children with well-developed collateral flow usually have a delayed clinical presentation into adolescence as the LV systolic function remains well preserved.[11],[12],[13] These patients usually are diagnosed when Echo is done for other reasons or for the presence of a cardiac murmur or exercise intolerance; very rarely they may present with sudden cardiac death as adults.[14] In patients with large postricuspid shunts (ventricular septal defect, patent ductus arterious, atrioventricular canal defect etc.,), pulmonary artery pressures remain elevated, leading to maintained antegrade flow from pulmonary artery to LCA and preservation of left ventricular function. With the closure of shunt lesion, these children develop severe left ventricular dysfunction, it is of utmost importance to profile coronary arteries origin in all patients undergoing surgical intervention.

Echocardiographic evaluation

The imaging modality of choice for the diagnosis of ALCAPA in infants is Transthoracic Echocardiography. Diagnosis is best made by in parasternal short-axis and long-axis planes, which demonstrates the anomalous origin of the LCA and its two branches from the PA with retrograde flow [Figure 3]a, [Figure 3]b and [Video 1], [Video 2].[15] In some cases, direct visualization of LCA from the pulmonary artery becomes a challenge as LCA falsely appears to connect to aortic sinus due to deficiency in lateral resolution.{Figure 3}

[MULTIMEDIA:1]

[MULTIMEDIA:2]

Other features on echo include:

Dilated RCA and its tortuosity seen on two-dimensional echo [Figure 3]cDilatation of left atrium and left ventricle left ventricular systolic dysfunction with global hypokinesia and segmental wall-motion abnormality [Figure 3]dMyocardial ischemia leads to wide enhancement of endocardium due to bright endocardial scarring. This scarring often includes mitral papillary muscle, which leads to ischemic mitral regurgitation [Figure 3]e and [Video 3]. These findings are suggestive of ALCAPA in patients with severe LV dysfunctionColor Doppler demonstrates reversal of flow from LCA [Figure 3]b and [Video 1], [Video 2]. LCA with normal origin demonstrates a red signal in parasternal short-axis view suggestive of blood flow away from the aortic root [Figure 1]b. In ALCAPA, there is retrograde LCA filling from PA, which is seen in color Doppler as emptying into the main PA (blue color in LCA and LAD).[15]

[MULTIMEDIA:3]

 Anomalous Origin of Right Coronary Artery from Pulmonary Artery



The anomalous origin of RCA from the pulmonary artery (ARCAPA) is the second most common of these conditions, with an incidence of 0.002%.[8] The clinical presentation can vary from being asymptomatic into adulthood to sudden cardiac death.

The timing of presentation depends on the severity of ventricular ischemia, which is determined by the shunt size, presence of collateral circulation, and myocardial oxygen demands. Since right ventricular oxygen demands are usually lower than the left ventricle demands, ventricular ischemia in ARCAPA is less common than in ALCAPA.

Echocardiographic evaluation

Dilated LCA and absence of RCA from right anterior sinusDelineation of the anomalous origin of RCA from the pulmonary artery is best seen by 2D echocardiography in parasternal short-axis view at the level of great vesselsOn color flow mapping, continuous flow at the site of connection of RCA into the pulmonary artery can be visualized. The quantity of flow depends on the degree of collaterals from LCA.

 Anomalous Origin of Left Anterior Descending Artery from Pulmonary Artery



Anomalous origin of the LAD artery from pulmonary artery is a very rare diagnosis which requires a very high index of suspicion. It has been reported to have an estimated frequency of about 0.0008%.[8] Clinical presentation varies from asymptomatic to presenting with congestive heart failure, acute myocardial infarction, and sudden death depending on the extent of collaterals.[16]

Echocardiography evaluation

While the coronary artery origin is seen normally arising from the left aortic sinus, posterior course or absence of bifurcation raises suspicion for this anomalyOther findings include prominent collaterals arising from dilated circumflex and RCA and reversal of flow in LAD artery on color flow mappingFeatures due to myocardial ischemia, including left ventricular dysfunction, sclerosis of the anterior papillary muscle of the mitral valve with mitral regurgitation may also be present.

 Anomalous Aortic Origin of Coronary Artery



Anomalous aortic origin of a coronary artery (AAOCA) is a congenital anomaly in which a coronary artery arises either from the opposite sinus of Valsalva or can rarely arise from the noncoronary sinus.

The incidence of AAOCA is reported as around 0.7%, and anomalous aortic origin of the RCA from the left sinus is much more common than the anomalous origin of the LCA from the right sinus.[17] It is usually a benign abnormality, however, can be associated with ischemic events and sudden death in young, especially in athletes <40 years of age following strenuous activity. The factors that increase the risk of such events include ostial stenosis, intramural (within anterior wall of the aorta), interarterial (within myocardium) course between great arteries, or acute angle of takeoff from the aorta.[18],[19]

This anomaly is most commonly incidentally detected when TTE is performed for other reasons. The coronary origins are best imaged in parasternal windows in transthoracic echocardiography. The evaluation includes the examination of ostium location and number and course and distribution of proximal coronary branches.

 Left Coronary Artery Arising from the Right Coronary Sinus (or Right Coronary Artery)



An aberrant origin of the LCA or LAD coronary artery from the right sinus of Valsalva is a rare anomaly that has been associated with myocardial ischemia and sudden cardiac death. Depending on the anatomic relationship of the anomalous vessel to the aorta and the pulmonary trunk, the anomaly can be classified into four anatomic subtypes by Robert and Shirani [Figure 4]a,[Figure 4]b,[Figure 4]c,[Figure 4]d.[20]{Figure 4}

Echocardiographic evaluation

Failure to demonstrate the LCA from its usual site of origin from the left sinusVisualization of Ostia and proximal segment of the right and left coronary arteries from the right sinus of Valsalva.

 Right Coronary Artery from the Left Coronary Sinus (or Left Coronary Artery)



As with the above entity, origin of RCA from the left sinus (or LCA) also has four possible courses [Figure 5]a,[Figure 5]b,[Figure 5]c,[Figure 5]d,[Figure 5]e.{Figure 5}

The acute bend of the proximal RCA at its ostium and compression of the coronary by the aorta and the pulmonary artery as it courses between these two structures are the usual causes which lead to myocardial ischemia in these patients.

 Isolated Left Circumflex Artery or Isolated Left Anterior Descending Artery from Right Coronary Artery



LCx from RCA or LAD artery from RCA are common anomaly of coronary artery and most common coronary anomaly seen in patients with TGA and tetralogy of Fallot, respectively.[21]

Echocardiographic evaluation

Four-chamber view (subcostal coronal and apical) in the posterior plane shows the course of LCx in the posterior atrioventricular groove as it arises from RCA [Figure 6]. It can also be visualized on parasternal short-axis view at the level of great vessels in which LCA continuation to LAD artery can be visualized LCx can be seen{Figure 6}

In imaging of LAD artery from RCA, Coronary from left-facing sinus would be continuing to the circumflex artery and LAD artery would be seen arising from RCA and crossing right ventricular outflow tract [Figure 7].{Figure 7}

 Coronary Artery Fistula



Coronary artery fistulas are direct connections from one or more coronary arteries to cardiac chambers, coronary sinus or a large vessel and represent an anomaly of termination[22],[23] Coronary arteriovenous fistulas are present in 0.002% of the general population.[24] CAF may be congenital or acquired; due to infectious, traumatic, and post angioplasty or postcardiac.

Coronary artery fistula involves more commonly the LCA (39%–63%); less often the RCA (29%–55%), and least often both (7%–19%).[25],[26],[27],[28] The common sites of drainage are the right ventricle in about 40% of instances, right atrium in about 25% of instances, the pulmonary artery in 15%–20% of instances.[26] Fistulas to the left atrium or left ventricle are rare.

The clinical presentation can range from asymptomatic, which are detected incidentally, to features of CHF due to volume overload or symptoms of pulmonary hypertension.

Echocardiographic evaluation

Dilated or tortuous proximal coronary artery in parasternal short-axis view or transesophageal echocardiography [Figure 8]aA continuous high-velocity signal is observed when the CAF drains into a low-pressure chamber, such as the right atrium [Figure 8]b and [Figure 8]c or coronary sinus; however, when it empties into a high-pressure chamber like the LV, the shunt flows only occurs during diastole[29]Volume overload of recipient cardiac chambers depending on the magnitude of left-to-right shunt through the fistula.[23]{Figure 8}

Rarely, the fistula may open into a large sac, which opens into one of the cardiac chambers.

 Atresia of Left Main Coronary Artery



Atresia of LCA with a lack of luminal continuity from the aortic root to LCA is very rare. The survival depends upon collaterals formation from the RCA through septal branches.[30]

Echocardiographic evaluation

Echocardiographic features are the same as in ALCAPA except no shunt between LCA and pulmonary artery and absence of reverse flow. Echocardiographic features of atresia of LCA are:

Dilated RCALeft ventricular dysfunctionMitral regurgitation due to the sclerosed papillary muscleCollaterals flow. This mimics the septal collaterals of the anomalous origin of LCA from the pulmonary artery on echocardiography, but there will be no reverse flow pattern seen in LCA and no left-to-right shunt in the pulmonary artery.

 Kawasaki Disease



Kawasaki disease is a childhood vasculitis of unknown etiology and mainly affects children younger than 5 years of age. It is the most commonly diagnosed cause of coronary aneurysms.[31] Coronary artery involvement with aneurysms develops in about 25% of patients with untreated Kawasaki's disease; the incidence of coronary involvement has reduced to 5%–7% after intravenous gamma globulin therapy when patients are treated within 10 days of fever onset.[32]

The Japanese guidelines classify coronary arteries by absolute lumen diameter.[33]

Small aneurysms-localized dilation of the internal lumen diameter but <4 mm, or dilation with an internal diameter of a segment measuring ≤1.5 times that of an adjacent segment if the child is ≥5 years of ageMedium aneurysms are defined as an internal lumen diameter between 4 and 8 mm, or an internal diameter of a segment measuring 1.5–4 times that of an adjacent segment if the child is ≥5 yearsLarge or giant aneurysms are defined as an internal lumen diameter >8 mm, or internal diameter of a segment measuring >4 times that of an adjacent segment if the child is >5 years.

These criteria do not account for patient size, which can substantially affect normal coronary artery dimensions, potentially leading to underdiagnosis and underestimation of the true prevalence of coronary artery dilation.[34]

The z-score stratification proposed by AHA guidelines (2017) to determine the degree of coronary involvement:[35]

No involvement: Z score always <2Dilation only: Z score 2 to < 2.5; or if initially < 2, a decrease in Z score during follow-up ≥ 1Small aneurysm: Z score ≥2.5 to <5Medium aneurysm: Z score ≥5 to <10, and absolute dimension <8 mmLarge or giant aneurysm: Z score ≥10, or absolute dimension ≥8 m

Most of the patients have dilatation only, which is characterized by measurement more than normal range but less than maximal Z score of <2.5 for age.

In Kawasaki disease, the most common sites of coronary artery aneurysms, in decreasing frequency, are the proximal LAD, proximal RCA, left main coronary artery (LMCA) followed by LCX[2],[30] Body surface area–adjusted Z scores are used to document z scores and diagnose ectasia for the proximal RCA, LMCA, and proximal LAD.[35],[36]

Echocardiographic evaluation

During echocardiographic evaluation of coronary arteries, all measurements are made to measure the internal vessel diameters [Figure 9]a and [Figure 9]b. All measurements should exclude points of branching and be measured from inner edge to inner edgeThe origins proximal portions of left main and its branches and RCA are best defined from parasternal short-axis view at the level of great vessels as described earlier. Apical 4-chamber view with posterior tilt is used to define the distal part of RCA in the right atrioventricular groove and of LCx in the left atrioventricular grooveLack of tapering seen in normal coronary arteries is suggestive of pathological dilatationCareful assessment of the internal lumen for thrombus formation is required in dilated coronary arteries, especially giant aneurysmsVentricular dysfunctionValve regurgitation (mitral, tricuspid, aortic). Aortic valve regurgitation is more commonly noted with aortic root dilatationPericardial effusion.{Figure 9}

 Conclusion



After a significant coronary artery abnormality is recognized in a pediatric patient, surgery or appropriate transcatheter intervention should be performed in patients with anomalous origin from the pulmonary artery and in case of anomalous course of the coronary artery between two great vessels. The risk from a congenital coronary abnormality far outweighs the risks of surgical or catheter intervention. In the hands of an experienced echocardiographer, two-dimensional and color-flow Doppler echocardiography is one of the best diagnostic tools for congenital coronary abnormalities, and various coronary anomalies are identifiable with echocardiography while some are suspected on echocardiography. For a complete evaluation, other cardiac imaging methods like CT, MRI, and conventional angiography may be needed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Miele F. Essentials of ultrasound physics. In: The Board Review Book Forney. TX: Pegasus Lectures; 2008.
2Fuse S, Kobayashi T, Arakaki Y, Ogawa S, Katoh H, Sakamoto N, et al. Standard method for ultrasound imaging of coronary artery in children. Pediatr Int 2010;52:876-82.
3Wilke J, Woodard L. Doppler effect: Doppler angle. In: Kremkau FW, editor. Diagnostic Ultrasound: Principles and Instruments. 6th ed. Philadelphia, PA: Saunders; 2002. p. 181-5.
4Brown LM, Duffy CE, Mitchell C, Young L. A practical guide to pediatric coronary artery imaging with echocardiography. J Am Soc Echocardiogr 2015;28:379-91.
5Akasaka T, Yoshikawa J, Yoshida K, Hozumi T, Takagi T, Okura H. Comparison of relation of systolic flow of the right coronary artery to pulmonary artery pressure in patients with and without pulmonary hypertension. Am J Cardiol 1996;78:240-4.
6Ofili EO, Labovitz AJ, Kern MJ. Coronary flow velocity dynamics in normal and diseased arteries. Am J Cardiol 1993;71:3D-9.
7Jureidini SB, Marino CJ, Waterman B, Syamasundar Rao P, Balfour IC, Chen SC, et al. Transthoracic Doppler echocardiography of normally originating coronary arteries in children. J Am Soc Echocardiogr 1998;11:409-20.
8Yamanaka O, Hobbs RE. Coronary artery anomalies in 126,595 patients undergoing coronary arteriography. Cathet Cardiovasc Diagn 1990;21:28-40.
9Baltaxe HA, Wixson D. The incidence of congenital anomalies of the coronary arteries in the adult population. Radiology 1977;122:47-52.
10Keith JD. The anomalous origin of the left coronary artery from the pulmonary artery. Br Heart J 1959;21:149-61.
11Wesselhoeft H, Fawcett JS, Johnson AL. Anomalous origin of the left cor- onary artery from the pulmonary trunk. Its clinical spectrum, pathology, and pathophysiology, based on a review of 140 cases with seven further cases. Circulation 1968;38:403-25.
12Roberts WC. Major anomalies of coronary arterial origin seen in adulthood. Am Heart J 1986;111:941-63.
13Berre LL, Baruteau AE, Fraisse A, Boulmier D, Jimenez M, Gallet B, et al. Anomalous origin of the left coronary artery from the pulmonary artery presenting in adulthood: A french nationwide retrospective study. Semin Thorac Cardiovasc Surg 2017;29:486-90.
14Krexi L, Sheppard MN. Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA), a forgotten congenital cause of sudden death in the adult. Cardiovasc Pathol 2013;22:294-7.
15Sanders SP, Parness IA, Colan SD. Recognition of abnormal connections of coronary arteries with the use of Doppler color flow mapping. J Am Coll Cardiol 1989;13:922-6.
16Ismail MY, Nassar MI, Hamad MA. Anomalous left anterior descending coronary artery arising from pulmonary artery in a 63 year-old male patient: Case report and literature review. Heart Views 2015;16:98-103.
17Cheezum MK, Liberthson RR, Shah NR, Villines TC, O'Gara PT, Landzberg MJ, et al. Anomalous aortic origin of a coronary artery from the inappropriate sinus of valsalva. J Am Coll Cardiol 2017;69:1592-608.
18Lorber R, Srivastava S, Wilder TJ, McIntyre S, DeCampli WM, Williams WG, et al. Anomalous aortic origin of coronary arteries in the young: Echocardiographic evaluation with surgical correlation. JACC Cardiovasc Imaging 2015;8:1239-49.
19Angelini P. Anomalous origin of the left coronary artery from the opposite sinus of valsalva: Typical and atypical features. Tex Heart Inst J 2009;36:313-5.
20Roberts WC, Shirani J. The four subtypes of anomalous origin of the left main coronary artery from the right aortic sinus (or from the right coronary artery). Am J Cardiol 1992;70:119-21.
21Jureidini SB, Appleton RS, Nouri S. Detection of coronary artery abnormalities in tetralogy of Fallot by two-dimensional echocardiography. J Am Coll Cardiol 1989;14:960-7.
22Latson LA. Coronary artery fistulas: How to manage them. Catheter Cardiovasc Interv 2007;70:110-6.
23Frommelt MA. Echocardiography in Pediatric and Adult Congenital Heart Disease. Philadelphia: Lippincott Williams & Willkins; 2012. p. 512.
24Ata Y, Turk T, Bicer M, Yalcin M, Ata F, Yavuz S. Coronary arteriovenous fistulas in the adults: Natural history and management strategies. J Cardiothorac Surg 2009;4:62.
25Sharma UM, Aslam AF, Tak T. Diagnosis of coronary artery fistulas: Clinical aspects and brief review of the literature. Int J Angiol 2013;22:189-92.
26Holzer R, Johnson R, Ciotti G, Pozzi M, Kitchiner D. Review of an institutional experience of coronary arterial fistulas in childhood set in context of review of the literature. Cardiol Young 2004;14:380-5.
27Cheung DL, Au WK, Cheung HH, Chiu CS, Lee WT. Coronary artery fistulas: Long-term results of surgical correction. Ann Thorac Surg 2001;71:190-5.
28Uysal F, Bostan OM, Semizel E, Signak IS, Asut E, Cil E. Congenital anomalies of coronary arteries in children: The evaluation of 22 patients. Pediatr Cardiol 2014;35:778-84.
29Shakudo M, Yoshikawa J, Yoshida K, Yamaura Y. Noninvasive diagnosis of coronary artery fistula by Doppler color flow mapping. J Am Coll Cardiol 1989;13:1572-7.
30Amabile N, Fraisse A, Quilici J. Hypoplastic coronary artery disease: Report of one case. Heart 2005;91:e12.
31Newburger JW, Takahashi M, Gerber MA, Gewitz MH, Tani LY, Burns JC, et al. Diagnosis, treatment, and long-term management of Kawasaki disease: A statement for health professionals from the Committee on Rheumatic Fever, Endocarditis and Kawasaki Disease, Council on Cardiovascular Disease in the Young, American Heart Association. Circulation 2004;110:2747-71.
32Newburger JW, Takahashi M, Beiser AS, Burns JC, Bastian J, Chung KJ, et al. A single intravenous infusion of gamma globulin as compared with four infusions in the treatment of acute Kawasaki syndrome. N Engl J Med 1991;324:1633-9.
33JCS Joint Working Group. Guidelines for diagnosis and management of cardiovascular sequelae in Kawasaki disease (JCS 2008)-Digest version. Circ J 2010;74:1989-2020.
34De Zorzi A, Colan SD, Gauvreau K, Baker AL, Sundel RP, Newburger JW. Coronary artery dimensions may be misclassified as normal in Kawasaki disease. J Pediatr 1998;133:254-8.
35McCrindle BW, Rowley AH, Newburger JW, Burns JC, Bolger AF, Gewitz M, et al. Diagnosis, treatment, and long-term management of Kawasaki disease: A scientific statement for health professionals from the American Heart Association. Circulation 2017;135:927-99.
36Manlhiot C, Millar K, Golding F, McCrindle BW. Improved classification of coronary artery abnormalities based only on coronary artery z-scores after Kawasaki disease. Pediatr Cardiol 2010;31:242-9.