Pictorial Essay: Sinus of Valsalva Anatomy and Pathological Conditions Diagnosis by Multi-Detector CT

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1 Pictorial Essay: Sinus of Valsalva Anatomy and Pathological Conditions Diagnosis by Multi-Detector CT Award: AOSR Best Exhibit Prize - Silver Poster No.: R-0211 Congress: RANZCR-AOCR 2012 Type: Educational Exhibit Authors: W. K. Tsang, A. Li Keywords: Cardiac, Cardiovascular system, CT, CT-Angiography, Computer Applications-Detection, diagnosis, Education and training DOI: /ranzcraocr2012/R-0211 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply RANZCR's endorsement, sponsorship or recommendation of the third party, information, product or service. RANZCR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold RANZCR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies,.ppt slideshows,.doc documents and any other multimedia files are not available in the pdf version of presentations. Page 1 of 27

2 Learning Objectives After reading this presentation, the reader will be able to: Understand the basic anatomy of the sinus of Valsalva and aortic root Recognize various pathological conditions of the Sinus of Valsalva and aortic root Background INTRODUCTION Multi-detector row CT (MDCT) cardiac imaging has emerged to be useful in the assessment of the anatomy and function of the heart. Apart from its established role in the evaluation of the coronary arteries, MDCT can also accurately assess the sinuses of Valsalva and aortic root. This pictorial essay serves to present the normal anatomy of Sinuses of Valsalva and aortic root, as well as their various pathological conditions. NORMAL ANATOMY The aortic root (Fig. 1 on page 3)is the outflow tract from the left ventricle. It surrounds and supports the aortic valvular leaflets, and connects the basal attachments of the leaflets within the left ventricle to the sinotubular junction. The anatomic ventriculoaortic junction is a circular locus within the aortic root, formed where the supporting ventricular structures give way to the fibro-elastic walls of the aortic sinuses. Aortic sinuses, or sinuses of Valsalva (SOV) (Fig. 2 on page,3)are three subtle dilations between the aortic valve annulus and the sinotubular ridge. Two of the SOV give rise to the coronary arteries and thus nominated as the right and left coronary aortic sinuses. The posterior sinus does not give rise to a coronary artery, therefore called the non-coronary aortic sinus. SOVs are important in allowing enough space for the aortic valve leaflets to open during systole without causing occlusion of the coronary artery ostia. They also prevent damage of the valve leaflets caused by direct striking of the aortic root wall. Page 2 of 27

3 Images for this section: Fig. 1: Normal aortic root. Oblique coronal image of MDCT coronary angiogram shows the structures at aortic root and proper measurements to be made. 1 = annulus, 2= sinus of Valsalva, 3 = sinotubular junction, 4 = ascending aorta, red arrow = valve commissures. Page 3 of 27

4 Fig. 2: Normal SOVs. Oblique axial image of MDCT coronary angiogram obtained at the level of the aortic valve shows the SOVs and the coronary arteries. R = right coronary cusp, L = left coronary cusp, N= noncoronary cusp, RCC = right coronary artery, LCC = left coronary artery Page 4 of 27

5 Table 1: Normal dimensions of aortic root structures. Page 5 of 27

6 Imaging Findings OR Procedure Details SINUS OF VALSALVA AND AORTIC ROOT PATHOLOGY 1. SINUS OF VALSALVA ANEURYSM (SVA) Sinus of Valsalva aneurysm (SVA) is a rare condition which is related to weakness of the elastic connective tissue at the junction of the aortic media and the annulus. Congenital causes including underlying deficiency of normal elastic tissue like in those with Marfan and Ehlers-Danlos syndromes. Acquired SVAs are most commonly related to infection, degeneration or trauma. Nonruptured SVAs may be asymptomatic, or they may present acutely with mass effect on adjacent cardiac structures. Ruptured SVAs result in aortocardiac shunt and may manifest as progressive congestive heart failure, severe acute chest pain with dyspnoea, or even cardiac arrest. In general, symptomatic or large SVAs should be repaired to avoid complications, whereas small asymptomatic SVAs may be monitored. Illustrative cases SVA with Patulous Right and Left Coronary Cusps A 48-year-old lady diagnosed with aortic regurgitation underwent echocardiogram as preoperational assessment of operation of varicose veins, which showed dilated aortic root with large sinus of Valsalva aneurysm and moderate to severe aortic regurgitation due to dilated aortic root. CT coronary angiography and thoracic aorta demonstrated patulous right and left coronary cusps and a wide-neck SVA of the non-coronary cusp (Fig. 3 on page 10 Fig. 4 on page 11 Fig. 5 on page 13). She underwent replacement of the aortic valve, aortic root and ascending aorta three months later. She was all along well in the subsequent 3 years post operative follow up period. Acute Ruptured SVA A 49-year-old gentleman presented with haemoptysis during his treatment for suspected tuberculous spondylodiscitis. Chest radiograph showed congested lung fields. Page 6 of 27

7 Echocardiogram revealed flailed aortic valve with moderate aortic regurgitation, aortic valvular leaflets thickening and vegetations. Features were compatible with infective endocarditis. CT coronary angiogram showed prolapsed aortic valve and a wide-neck aneurysm with lobulated contour arising from the undersurface of the right coronary sinus. A fistula connecting the basal aspect of the aneurysm running to the right atrium was noted (Fig. 6 on page 13). Overall features were consistent with ruptured SVA with fistula to right atrium. He then underwent emergency open heart surgery with drainage of perivalvular abscess, closure of the fistula and aortic valvular replacement. Post-operative recovery was stormy. Patient eventually succumbed due to disseminated intravascular coagulation. 2. SOV PSEUDOANEURYSM Infective SOV pseudoaneurysm is a rare condition resulting from extension of infection from a paravalvular myocardial abscess complicating endocarditis. Clinically patients have insidious onset of vague symptoms. Complications include rupture or formation of fistula to right heart with left to right shunt. Prognosis is poor if untreated. Illustrative case SOV Pseudoanerusym with Aortic Root Abscess A 30-year-old gentleman with history of substance abuse and gonorrhoea presented with subacute onset of dyspnoea. Physical examination found ejection diastolic murmur at the left lower sternal border. Coronary CT angiogram demonstrated a huge narrow-necked contrast-filled sac arising from the left SOV, suggestive of SOV pseudoaneurysm (Fig. 7 on page 14). Soft tissue infiltrates in the mediastinal spaces surrounding the aortic arch and roots of the great vessels raised the suspicion of mediastinitis and aortic root micro-abscesses (Fig. 8 on page 15). Non-specific multifocal ground-glass opacities and interstitial thickening were present in the included lung fields (Fig. 9 on page 16), which could represent pulmonary edema related to acute heart failure or concurrent chest infection. Emergency aortic valvular replacement was performed. Unfortunately, valve dehiscence occurred and the patient underwent another open heart surgery within two months. He finally succumbed four months later due to irreversible left ventricular failure. 3. BICUSPID AORTIC VALVE Page 7 of 27

8 Bicuspid aortic valve (BAV) is the most common congenital anomaly of the aortic valve, resulting from complex abnormal cusp formation during valvulogenesis. Since BAV causes premature fibrosis and calcification of the aortic valves, aortic stenosis is the most common complication. The classical bicuspid valve shows two symmetric aortic cusps. During diastole, the open bicuspid aortic valve assumes a typical ellipsoid shape. Aortic stenosis from bicuspid valve presents at an age range of 30 to 50 years, earlier than those caused by degeneration. In the evaluation of patients with bicuspid valves that require valve repair, the degree of calcification of the valve is important as coronary implantation and aortic root replacement may be indicated in those with significant calcification. Illustrative case BAV with Ascending Aortic Aneurysm A 53-year-old lady with known history of moderate aortic stenosis and severe aortic regurgitation was noted to have dilated aortic root of in echocardiogram. Cardiac CT was arranged for preoperational planning of aortic graft during aortic vulvular replacement, which showed thickened calcified bicuspid aortic valve with incomplete closure (Fig. 10 on page 17). Fusiform ascending aortic aneurysm and concentric left ventricular hypertrophy were also revealed (Fig. 11 on page 18). Aortic valvular replacement was arranged. Four months later, before receiving the surgery, she presented with acute chest pain. Urgent CT thorax demonstrated Standford type A aortic intramural heamatoma (Fig. 12 on page 19). Cardiothoracic team assessed her and decided not for urgent open heart surgery in view of her unstable condition. The patient condition deteriorated rapidly. She succumbed two days after admission. 4. CORONARY ARTERY ANOMALIES Congenital anomalies of the coronary arteries are uncommon yet important causes of chest pain, with prevalence of 0.3-1% in general population. They can be classified anatomically according to their origin, course, and termination. They could also be divided as hemodynamically significant or insignificant (Table 2 on page 20). The former ones are characterized by abnormalities of myocardial perfusion, which lead to an increased risk of myocardial ischemia or sudden death. Illustrative cases Page 8 of 27

9 Anomalous Right Coronary Artery with Malignant Course CT coronary angiogram of a 57-year-old lady who presented with chest pain revealed the common origin of both the right and left coronary arteries (RCA and LCA) from the left coronary cusp (Fig. 13 on page 20). The proximal RCA ran between the pulmonary trunk and aortic root, consistent with anomalous origin of RCA with "malignant" interarterial course (Fig. 14 on page 21). The patient deferred the option of operation. No record of adverse cardiac event was noted in the subsequent 2-year follow up period. Separate Left Anterior Descending and Left Circumflex Arteries A 79-year-old lady with history of aortic valvular replacement due to aortic stenosis developed silent anterior territory myocardial ischemia soon after she underwent left mastectomy for treatment of breast carcinoma. Coronary CT angiogram revealed seperate ostia of left anterior descending (LAD) and left circumflex arteries (LCx) arising from the left coronary sinus (Fig. 15 on page 22), a normal variant without hemodynamic effect upon coronary perfusion. No adverse cardiac event was documented in the subsequent 4 years. 5. CORONARY ARTERY ANEURYSM WITH ASSOCIATED FISTULA (CAAAF) Approximately 3% of coronary artery fistulas (CAFs) are associated with coronary artery aneurysm (CAA), a rare condition with only about 50 cases have been reported in the English literatures. It is congenital in most cases. Acquired causes include complications of previous open heart surgery, endomyocardial biopsy, percutaneous transluminal coronary angioplasty (PTCA), myocardial infarction and trauma. One-third of the patients with CAAAF are asymptomatic, and two-third of patients may experience symptoms such as angina, dyspnoea on exertion or palpitation. Aneurysm repair, closure of fistula and coronary artery bypass graft are the definitive treatment opinions. Illustrative case Right Coronary Artery Aneurysm with associated Fistula Page 9 of 27

10 No abnormality was detected in thallium scan and echocardiogram of a 73-year-old gentleman who presented with chest pain. Further workup with CT coronary angiogram showed a huge fusiform aneurysm arising from the proximal RCA (Fig. 16 on page 23) with direct drainage into the coronary sinus and the inferior aspect of the heart (Fig. 17 on page 24). Features are compatible with right coronary artery aneurysm with associated coronary artery fistula (CAAAF). The patient subsequently underwent left and right cardiac catheterization, which confirmed the presence of a 3cm proximal right coronary artery aneurysm which drained into the coronary sinus. Cardiothoracic surgery referral was arranged. However, the option of definite surgery was declined by patient despite the risk of rupture or thrombosis of aneurysm explained. Fortunately he was stable in the subsequent 3 years without major adverse cardiac events. Images for this section: Page 10 of 27

11 Fig. 3: Oblique axial image obtained at the level of the aortic valve, demonstrates patulous right (R) and left (L) coronary cusps and a wide-neck SVA of the non-coronary cusp (N). Page 11 of 27

12 Page 12 of 27

13 Fig. 4: Oblique sagittal image of MDCT coronary angiogram, showing wide-neck SVA of the non-coronary cusp (N). Fig. 5: CT coronary angiogram with volume rendered image, demonstrating patulous right (R) and left (L) coronary cusps and a wide-neck SVA of the non-coronary cusp (N). Page 13 of 27

14 Fig. 6: CT coronary angiogram with multiplanar reconstruction in oblique coronal view demonstrates sinus of valvalsa aneurysm (*) with contrast jet (arrow) directing towards the right atrium (RA), consistent with ruptured SVA aneuerysm with fistula to right atrium. Page 14 of 27

15 Fig. 7: Axial MDCT image showing a huge narrow-necked contrast-filled sac (*) from the left SOV (L), suggestive of SOV pseudoaneurysm. Page 15 of 27

16 Fig. 8: Soft tissue infiltrates (arrowheads) in the mediastinal spaces surrounding the aortic arch and root of the great vessels raise the suspicion of mediastinitis and aortic root micro-abscesses. Page 16 of 27

17 Fig. 9: Non-specific multifocal ground-glass opacities in the included lung fields can represent pulmonary edema related to acute heart failure or concurrent chest infection. Page 17 of 27

18 Fig. 10: CT coronary angiogram with multiplanar reconstruction image in oblique sagittal view, demonstrates bicuspid aortic valve with thickening and calcification (arrowheads). Page 18 of 27

19 Fig. 11: CT coronary angiogram with multiplanar reconstruction image, demonstrates bicuspid aortic valve with thickening and calcification (arrow), fusiform ascending aortic aneurysm (AA) and concentric left ventricular hypertrophy (arrowheads). Page 19 of 27

20 Fig. 12: Pre contrast CT thorax. Axial image at the level of aortic arch shows standford type A aortic intramural heamatoma. Table 2: Coronary Artery Anomalies. Those highlighted in red are hemodynamically significant which could lead to abnormal myocardial perfusion and even sudden death. Page 20 of 27

21 Fig. 13: Common origin of RCA & LCA from the left coronary cusp (L). Page 21 of 27

22 Fig. 14: CT coronary angiogram with volume rendered image. Common origin (black arrow) of RCA & LCA (*) from the left coronary cusp. The proximal RCA ran between the pulmonary trunk (P) and aortic root (A), consistent with "malignant" interarterial course (arrowheads). Page 22 of 27

23 Fig. 15: Separate ostia of LAD and LCx from left coronary sinus. This is considered as normal variant without hemodynamic effect upon coronary perfusion. Page 23 of 27

24 Fig. 16: A huge fusiform aneurysm (* ) arising from the proximal RCA (arrowhead). R = right coronary cusp, L = left coronary cusp, N = non-coronary cusp. Page 24 of 27

25 Fig. 17: CT coronary angiogram with volume rendered image, showing a 5cm right coronary artery (RCA) aneurysm (*) near the ostium of the RCA (arrows). Also of note is presence of coronary artery fistula (arrowheads) that subsequently drains via the coronary sinus into the right atrium. Page 25 of 27

26 Conclusion Pathological conditions of Sinus of Valsalva and aortic root are rare yet important. The clinical manifestations vary from asymptomatic incidental finding to acute rapidly deteriorating course and death. Surgical repair is the mainstay of treatment, which can be lifesaving in some conditions. Therefore a prompt and accurate diagnosis of the disease is paramount. Multi-detector row CT (MDCT) cardiac imaging is excellent in demonstrating the anatomy and function of the heart, and also a powerful tool in diagnosis of various pathology of the sinus of Valsalva and aortic root. Personal Information Dr Tsang Wai Kan graduated from the Chinese University of Hong Kong in She became a Fellow of the Royal College of Radiologists (UK) in She is now receiving her higher training in Tuen Mun Hospital, Hong Kong. Her major interests include musculoskeletal radiology, interventional radiology and cardiovascular imaging. Dr Allen Li graduated from the Chinese University of Hong Kong in He is now the consultant radiologist in North District Hospital, Hong Kong. He is also the organizer of the MRI training program in his center. His major interests include cardiovascular imaging and chest radiology. References 1. Anderson. The surgical anatomy of the aortic root. Multimedia Manual of Cardiothoracic Surgery N Manghat, V Rachapalli, R Van Lingen et al. Imaging the heart valves using ECGgated 64-detector row cardiac CT. The British Journal of Radiology, 81 (2008), Mateen Akhtar, E. Murat Tuzcu, Samir R. Kapadia et al. Aortic root morphology in patients undergoing percutaneous aortic valve replacement: Evidence of aortic root remodeling. Journal of Thorac. Cardiovasc. Surg. 2009;137: P Nataf, E Lansa. Dilation of the thoracic aorta: medical and surgical management. Heart 2006;92: Page 26 of 27

27 5. Bricker, Avutu et al. Valsalva Sinus Aneurysms: Findings at CT and MR Imaging. RadioGraphics 2010; 30: Salanitri, Huo et al. MRI of Mycotic Sinus of Valsalva Pseudoaneurysm Secondary to Aspergillus Pericarditis. AJR:184, March Kim, Seo, Do et al. Coronary Artery Anomalies: Classification and ECG-gated Multi-Detector Row CT Findings with Angiographic Correlation. RadioGraphics 2006; 26: Díaz-Zamudio, Bacilio-Pérez et al. Coronary Artery Aneurysms and Ectasia: Role of Coronary CT Angiography. RadioGraphics 2009; 29: Zenooz, Habibi et al. Coronary Artery Fistulas: CT Findings. RadioGraphics 2009; 29: Page 27 of 27