Supravalvular Aortic Stenosis with Aneurysmal Dilation, and Infective Vegetations in the Aortic Arch in a Pediatric Patient with Wiliams Syndrome: A Case Report and Literature Review

Supravalvular Aortic Stenosis with Aneurysmal Dilation, and Infective Vegetations in the Aortic Arch in a Pediatric Patient with Wiliams Syndrome: A Case Report and Literature Review | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL This is a preprint and has not been peer reviewed. Data may be preliminary. 3 September 2025 V2 Latest version Share on Supravalvular Aortic Stenosis with Aneurysmal Dilation, and Infective Vegetations in the Aortic Arch in a Pediatric Patient with Wiliams Syndrome: A Case Report and Literature Review Authors : Ahmad Bishr Nasra 0009-0002-8243-9385 [email protected] , Alwaleed Al-Dairy 0000-0002-2239-646X , Aram Al Mohamad 0009-0004-4276-4102 , Ahmad Jabr , and Younes Al-Dairy Authors Info & Affiliations https://doi.org/10.22541/au.174235323.34132807/v2 435 views 150 downloads Contents Abstract Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Background: Williams syndrome (WS) is a rare genetic condition frequently associated with cardiovascular anomalies, particularly supravalvular aortic stenosis (SVAS). The coexistence of SVAS, aneurysmal dilation, and infective endocarditis (IE) with vegetations in the aortic arch is exceedingly rare. Case presentation: We describe an an 8-year-old Arab boy from Syria with WS who presented with fatigue, tachycardia, dyspnea, fever, chills, and night sweats. Transthoracic echocardiography revealed a dilated aortic arch with large vegetation at the origin of the brachiocephalic trunk and SVAS. Despite 10 days of intravenous antibiotic therapy, vegetations persisted, necessitating urgent surgery. The ascending aorta was replaced using the McGoon technique with complete excision of infected tissue. Postoperative recovery was uneventful, and follow-up imaging showed good left ventricular function without aortic gradient. Conclusion: This case underscores the importance of early recognition and timely surgical intervention in preventing catastrophic outcomes in patients with WS and complex cardiovascular involvement. Keywords: Williams syndrome, supravalvular aortic stenosis, aneurysm, vegetations, endocarditis, case report. Background Williams syndrome (WS), known as Williams-Beuren syndrome, is a rare genetic disorder which affects the vascular connective tissue. It can arise either sporadically or be passed down through families, with an estimated occurrence of about 1 in every 8,000 to 10,000 live births. This condition is typically marked by short stature, a range of intellectual disabilities, unique facial features that often give an "elfin" appearance, and various congenital heart defects (CHDs) (1–3). We can detect CHD in approximately 80% of patients with WS, especially Supravalvular aortic stenosis which occurs in 30-60% of cases (4,5). Patients with WS and CHDs are at an increased risk of developing infective endocarditis (IE), with an estimated annual incidence of 3 to 10 cases per 100,000 individuals (6). Chronic and severe cases of infective endocarditis can lead to the formation of bacterial vegetations composed of inflammatory cells, fibrin, platelets, and erythrocyte debris (7). This case highlights the rare coexistence of SVAS, aneurysmal arch dilation, and intraluminal vegetations in WS, emphasizing timely surgical decision-making when antibiotic therapy fails. Case Presentation An 8-year-old Arab boy from Syria with a known diagnosis of Williams syndrome (WS) and supravalvular aortic stenosis (SVAS) presented to our hospital with fatigue, tachycardia, dyspnea, fever, chills, and night sweats. He had been treated for typhoid fever three months earlier, with no other relevant medical history. On admission, the patient was febrile (38.5°C) and tachycardic (140 bpm), with a respiratory rate of 30 breaths per minute, blood pressure of 90/60 mmHg, and oxygen saturation of 94% on room air. Physical examination revealed pallor, tachypnea, and digital clubbing, along with hepatosplenomegaly on abdominal palpation. The patient exhibited characteristic facial features of WS, including a prominent forehead, and had speech difficulties. Cardiac auscultation detected a grade 4–5/6 systolic murmur at the right upper sternal border, radiating to the neck. Blood tests showed leukocytosis, elevated C-reactive protein levels, and severe anemia, suggesting an ongoing infectious process. Transthoracic echocardiography (TTE) revealed left ventricular dilation with mild dysfunction (ejection fraction ~50%), severe SVAS with a gradient of ~90 mmHg, and an aneurysmal, thin-walled aortic arch with multiple vegetations. Abdominal ultrasound and Doppler studies showed normal renal arteries and no additional abnormalities. Computed tomography angiography (CTA) was performed to obtain further anatomical details (Figure 1). Initially, the patient received 10 days of appropriate intravenous antibiotic therapy; however, persistent vegetations necessitated surgical intervention. The operation was performed through a median sternotomy. The pericardium was opened, revealing aneurysmal dilatation in the ascending aorta, both proximal and distal to the site of supravalvular aortic stenosis (SVAS) (Figure 2). Deep hypothermic circulatory arrest (DHCA) was planned to provide excellent exposure of the aortic arch for the removal of vegetations and diseased tissue. Following systemic heparinization, arterial cannulation was performed near the brachiocephalic artery origin, with venous drainage via a right atrial cannula. Cardiopulmonary bypass (CPB) was initiated, the aortic cross-clamp was applied, and the heart was arrested using antegrade cold blood cardioplegia. The aorta was transected above the site of the stenosis (Figure 3), and a vertical incision was made in the proximal aorta (crossing the stenosis) toward the non-coronary sinus. A bovine pericardial patch was used to augment this portion of the aorta, effectively relieving the SVAS After cooling to 18°C, DHCA was initiated, and the aortic cross-clamp was removed. Large vegetations in the aortic arch, along with heavily diseased tissue, were completely resected (Figure 4). The excised aortic arch segment was reconstructed using a polytetrafluoroethylene (PTFE) conduit in a hemiarch replacement technique, ensuring secure anastomosis and optimal hemodynamic function (Figure 5). Following the distal anastomosis, CPB was restarted, and the patient was gradually rewarmed. The aortic cross-clamp was re-applied to the conduit, and an end-to-end anastomosis was performed between the proximal end of the conduit and the augmented ascending aorta. To prevent air embolism, a combination of antegrade and retrograde deairing maneuvers was performed, including direct aspiration from the graft and transesophageal echocardiography (TEE) confirmation of complete deairing. Once ensured, the aortic cross-clamp was removed, and the heart resumed beating in sinus rhythm. The patient was successfully weaned off bypass with low-dose inotropic support. The remainder of the operation was uneventful. Postoperatively, the patient was transferred to the intensive care unit (ICU) for mechanical ventilation and intensive neurological and hemodynamic monitoring. He was extubated after 48 hours without neurological complications. The patient was then transferred to the septic division for continued targeted antibiotic therapy based on the culture results from the resected tissues. Transthoracic echocardiography (TTE) showed good left ventricular (LV) function without any gradient across the ascending aorta or arch. The hospital course was uneventful, and the patient was discharged after 11 days. Long-term follow-up is planned with periodic imaging and clinical evaluations. Discussion Williams–Beuren syndrome (WS) is a rare and intricate developmental disorder that includes cardiovascular manifestations. Additionally, it is characterized by intellectual disability, a distinctive cognitive and/or behavioral profile, unique facial features, and occasional hypercalcemia (8). Supravalvular aortic stenosis (SVAS) is the rarest of the three types of congenital aortic stenosis. It occurs in association with Williams syndrome in 30–50% of cases. Approximately 20% of these cases are familial without features of Williams syndrome, while the remaining cases (i.e., about half of all patients) are considered sporadic (9–11). The high-velocity jets associated with SVAS can cause endothelial injury in the ascending aorta and, less commonly, in the aortic arch, resulting in platelet and fibrin deposition, subsequently forming nonbacterial thrombotic endocardial lesions. If bacteremia occurs, organisms may attach to these lesions, leading to infective vegetation. While the stenosis itself may not directly promote the progression of endocarditis, it can influence its development following endothelial injury, as seen in hemodynamic studies involving children with Williams syndrome and vegetation growth (12–14). There are only few reported cases in the medical literature linking Williams syndrome (WS) to infective endocarditis (IE), particularly in relation to supravalvular aortic stenosis (SVAS). In the following section, we will summarize some notable cases to offer context and shed light on the various management strategies employed. The earliest documented case of infective endocarditis (IE) was published by Kwang Kon Koh and colleagues. It described an 18-year-old man with WS who presented with fever and chills. Despite lacking any medical history that could predispose him to infection, he was diagnosed with IE. The patient was treated successfully with antibiotics, underscoring the potential for non-surgical management in specific cases of IE (15). by Das and Makhija documented a rare case involving a 4-year-old boy who presented with easy fatigability, respiratory distress, and intermittent fever lasting two months. The patient was diagnosed with IE and an aortic arch pseudoaneurysm, with vegetation near a major blood vessel. Initial management included intravenous antibiotics and diuretics. After 10 days, the patient underwent a modified Brom procedure with ascending aorta and arch replacement (3). A 5-year-old boy with WS was reported to develop an IE 15 days after cardiac catheterization by Figueroa et al. The patient presented with fever and right-side paresis. Imaging revealed a fusiform cerebral aneurysm, which required neurosurgical intervention. Additionally, vegetations were excised, and the ascending aorta and arch were reconstructed using the Doty repair technique (16). More recently, a case published by Matsunaga et al. detailed a 13-year-old boy with WS and SVAS, complicated by IE and aortic dissection. The patient presented with persistent fever and abdominal pain, which lasted for a week. He was evaluated by his local pediatrician, who diagnosed him with hypertension associated with SVAS. The patient ultimately required ascending aorta replacement as part of his surgical management. (17) Our case involved an 8-year-old child with Williams Syndrome (WS) presenting with fatigue, tachycardia, dyspnea, fever, chills, and night sweats. Three months prior, he had been treated for typhoid fever, with no other relevant medical history. TEE revealed a dilated aortic arch with large vegetation at the origin of the brachiocephalic trunk and supravalvular aortic stenosis (SVAS). Despite starting intravenous antibiotics, a follow-up transthoracic echocardiogram (TTE) that was taken 10 days later unveiled that the vegetation had not improved significantly. Given the risks of embolization and the potential for severe complications like stroke or damage to various organs, it became essential to move forward with surgical intervention promptly (table 1) Table 1. Reported cases of Williams syndrome with supravalvular aortic stenosis complicated by infective endocarditis Author / Year Age / Sex Presentation Associated Findings Management Koh et al., 1988 18 / M Fever, chills None significant Intravenous antibiotics Das & Makhija, 2023 4 / M Fatigability, respiratory distress, fever Aortic arch pseudoaneurysm, vegetations Modified Brom procedure (aorta & arch replacement) Figueroa et al., 2008 / 2015 5 / M Fever, right-sided paresis Cerebral aneurysm, vegetations Doty repair, neurosurgical intervention Matsunaga et al., 2023 13 / M Fever, abdominal pain Aortic dissection, SVAS, vegetations Ascending aorta replacement Present case, 2025 8 / M Fatigue, dyspnea, fever, night sweats Arch aneurysm, SVAS, large vegetations McGoon technique with hemiarch replacement Conclusion The intersection of Williams syndrome, supravalvular aortic stenosis, and infective vegetations in the aortic arch creates a unique and complex clinical situation that demands careful diagnostic assessment and thoughtful surgical intervention. Early and decisive intervention is critical to prevent catastrophic complications, such as embolization or rupture of the aortic arch. Complete removal of the vegetations and reconstruction of the affected aortic segments are essential for achieving a successful outcome. List of Abbreviations WS – Williams syndrome SVAS – Supravalvular aortic stenosis IE – Infective endocarditis CHD – Congenital heart defect TTE – Transthoracic echocardiography CTA – Computed tomography angiography DHCA – Deep hypothermic circulatory arrest CPB – Cardiopulmonary bypass PTFE – Polytetrafluoroethylene TEE – Transesophageal echocardiography Declarations Ethics approval and consent to participate This case report was conducted in accordance with ethical principles and the Declaration of Helsinki. Ethical approval for the publication of this case was obtained from the Ethics Committee of Damascus University, Faculty of Medicine. Written informed consent to participate was provided by the patient’s parents. Consent for publication Written informed consent was obtained from the patient’s legal guardian for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Availability of data and materials Available from the corresponding author upon reasonable request. Competing interests The authors declare that they have no competing interests. Funding No funding sources. Authors Contributions ABN, AA-D: Planned and performed the work leading to the report. Wrote and reviewed successive versions and participated in their revisions. AAM, AJ, YA-D: wrote and reviewed the successive versions and participated in their revisions Acknowledgments The authors thank Medical Research Empowerment for their support in this publication. References 1. Collins RT 2nd, Kaplan P, Somes GW, Rome JJ. Long-term outcomes of patients with cardiovascular abnormalities and williams syndrome. Am J Cardiol. 2010 Mar 15;105(6):874-8. doi: 10.1016/j.amjcard.2009.10.069. PMID: 20211336. 2. Pober BR. Williams-Beuren syndrome. N Engl J Med. 2010 Jan 21;362(3):239-52. doi: 10.1056/NEJMra0903074. Erratum in: N Engl J Med. 2010 Jun 3;362(22):2142. PMID: 20089974. 3. Das D, Makhija N. Williams-Beuren syndrome with pseudoaneurysm of aortic arch and infective vegetations for modified broms procedure: anesthetic concerns & Echocardiographic illustrations. Ann Card Anaesth. 2023 Jan-Mar;26(1):94-96. doi: 10.4103/aca.aca_122_21. PMID: 36722596; PMCID: PMC9997478. 4. De Rubens Figueroa J, Rodríguez LM, Hach JL, Del Castillo Ruíz V, Martínez HO. Cardiovascular spectrum in Williams-Beuren syndrome: the Mexican experience in 40 patients. Tex Heart Inst J. 2008;35(3):279-85. PMID: 18941598; PMCID: PMC2565537. 5. Bera D, Majumder B, Bhandari M, Venkatraman D, Das R, Mandal PC, Halder P. Infective endarteritis in a case of supravalvular aortic stenosis. J Cardiol Cases. 2014 Oct 11;11(1):21-24. doi: 10.1016/j.jccase.2014.09.003. PMID: 30546528; PMCID: PMC6280007. 6. Rajani R, Klein JL. Infective endocarditis: A contemporary update. Clin Med (Lond). 2020 Jan;20(1):31-35. doi: 10.7861/clinmed.cme.20.1.1. PMID: 31941729; PMCID: PMC6964163. 7. Yallowitz AW, Decker LC. Infectious Endocarditis. [Updated 2023 Apr 24, cited 2025 Feb 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557641/ 8. Morris CA, Demsey SA, Leonard CO, Dilts C, Blackburn BL. Natural history of Williams syndrome: physical characteristics. J Pediatr. 1988 Aug;113(2):318-26. doi: 10.1016/s0022-3476(88)80272-5. PMID: 2456379. 9. Ewart AK, Morris CA, Atkinson D, Jin W, Sternes K, Spallone P, Stock AD, Leppert M, Keating MT. Hemizygosity at the elastin locus in a developmental disorder, Williams syndrome. Nat Genet. 1993 Sep;5(1):11-6. doi: 10.1038/ng0993-11. PMID: 7693128. 10. 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Maruyoshi H, Nakatani S, Yasumura Y, Nakajima H, Niwaya K, Sasako Y, Ando M, Miyatake K, Yamagishi M. [Intractable infective endocarditis associated with supravalvular aortic stenosis in Williams syndrome: a case report]. J Cardiol. 2002 Jul;40(1):25-30. [Article in Japanese]. 14. Yozgat CY, Uzuner S, Yesilbas O, Bursal Duramaz B, Yozgat Y, Iscan A, Turel O. Williams Syndrome Presenting with Intractable Staphylococcus aureus Endocarditis. Indian J Pediatr. 2020 Aug;87(8):654-655. doi: 10.1007/s12098-020-03207-0. Epub 2020 Feb 14. PMID: 32060709. 15. Koh KK, Lee JH, Sohn DW, Oh BH, Park YB, Choi YS, Seo JD, Lee YW, Park JH. Infective endocarditis in a patient with Williams' syndrome--case report. Korean J Intern Med. 1988 Jul;3(2):142-7. doi: 10.3904/kjim.1988.3.2.142. PMID: 3154192; PMCID: PMC4534958. 16. De Rubens Figueroa J, Marhx A, López Terrazas J, Palacios Macedo A. Supravalvular aortic stenosis associated to infectious endocarditis and cerebral vascular disease in a patient with Williams-Beuren Syndrome. Arch Cardiol Mex. 2015 Oct-Dec;85(4):292-5. doi: 10.1016/j.acmx.2014.12.002. Epub 2015 Apr 13. PMID: 25882107. 17. Matsunaga Y, Suzuki H, Shikata F, Honda T, Hirata Y, Okamura T, Ishikura K, Miyaji K. Aortic Dissection and Supravalvular Aortic Stenosis With Williams Syndrome Complicated by Infection. Ann Thorac Surg Short Rep. 2023 Aug 16;1(4):674-678. doi: 10.1016/j.atssr.2023.07.012. PMID: 39790653; PMCID: PMC11708675. Image (1.png) is missing or otherwise invalid. Contrast-enhanced computed tomography angiography (CTA) of the thoracic aorta demonstrating aneurysmal dilation of the aortic arch with irregular wall thickening and intraluminal vegetations (arrow) at the origin of the brachiocephalic trunk. Severe supravalvular aortic stenosis (SVAS) is evident proximal to the dilated segment. Image (2.png) is missing or otherwise invalid. Intraoperative view after median sternotomy and pericardiotomy, revealing aneurysmal dilatation of the ascending aorta both proximal and distal to the site of supravalvular aortic stenosis (SVAS). The thin-walled segment is markedly enlarged, consistent with severe structural weakening. Image (3.png) is missing or otherwise invalid. Intraoperative view of the ascending aorta after transection above the site of supravalvular aortic stenosis (SVAS). A vertical incision was extended toward the non-coronary sinus, with stay sutures placed for exposure. This step prepared the field for augmentation with a bovine pericardial patch to relieve the stenosis. Image (4.png) is missing or otherwise invalid. Resected aortic arch specimen with large friable vegetations and severely diseased tissue. The irregular masses represent infected endocarditic vegetations adherent to the aortic wall, highlighting the destructive nature of infective endocarditis in the setting of Williams syndrome and SVAS. Intraoperative view following resection of the diseased aortic arch and supravalvular stenotic segment. A polytetrafluoroethylene (PTFE) conduit has been anastomosed to the proximal ascending aorta and distal arch under cardiopulmonary bypass. Cannulation sites and bypass tubing are visible, demonstrating the reconstruction phase of the hemiarch replacement procedure. This is a caption Information & Authors Information Version history V1 Version 1 19 March 2025 V2 Version 2 03 September 2025 Copyright This work is licensed under a Creative Commons Attribution 4.0 International License Keywords cardiology cardiothoracic surgery cardiovascular disorders Authors Affiliations Ahmad Bishr Nasra 0009-0002-8243-9385 [email protected] Damascus University Faculty of Medicine View all articles by this author Alwaleed Al-Dairy 0000-0002-2239-646X Damascus University Faculty of Medicine View all articles by this author Aram Al Mohamad 0009-0004-4276-4102 Damascus University Faculty of Medicine View all articles by this author Ahmad Jabr Damascus University Faculty of Medicine View all articles by this author Younes Al-Dairy Damascus University Faculty of Medicine View all articles by this author Metrics & Citations Metrics Article Usage 435 views 150 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Ahmad Bishr Nasra, Alwaleed Al-Dairy, Aram Al Mohamad, et al. Supravalvular Aortic Stenosis with Aneurysmal Dilation, and Infective Vegetations in the Aortic Arch in a Pediatric Patient with Wiliams Syndrome: A Case Report and Literature Review. Authorea . 03 September 2025. DOI: https://doi.org/10.22541/au.174235323.34132807/v2 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu . 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