SVA is a rare cardiac disease that caused by weakening of the elastic lamina and muscular tissue in the aortic wall behind the sinus of Valsalva. 2,3 The great mass of the cases are congenital and secondary to connective tissue diseases such as Marfan’s syndrome or multifarious others. However, acquired cases of SVA generally due to infective endocarditis (IE), atherosclerosis, traumatic, the abuse of drugs or alcoholism, medial cystic necrosis and degenerative diseases.4 Our two patients are both associated with IE confirmed by the intraoperation and histopathology. Infection may lead to Sinus of Valsalva dilatation and aortic valve cusps deformation that subsequently to SVA rupture and IVS dissection. Progression of the disease may also increasingly predisposed to recurrent endocarditis. 5The diagnosis of endocarditis mainly depends on finding vegetations and positive blood culture. Due to the influence of blood collection time, quantity and antibiotic application, it has been reported that the positive rate of blood culture is in between 50% and 90%. In our two cases, multiple blood cultures were also negative. Positive blood cultures can help clinical selection of antibiotics, but negative results cannot easily rule out the diagnosis of endocarditis.
Most SVA originates from the right coronary sinus, followed by the non-coronary sinus, the left coronary sinus is least common.6SVA is generally asymptomatic. But enlarged coronary sinus protrude into the adjacent cardiac structure, lead to neighboring cavity obstructions, myocardial infarction or ischemia by compress of the coronary arteries, or extremely rare dissect into the IVS. Strenuous activity, emotional excitement, infection, trauma, iatrogenicity(cardiac catheterization) can induce SVA rupture. The majority of right SVA rupture into the right ventricular outflow tract (RVOT) followed by the RV and right atrium (RA). SVA dissecting into the IVS as exemplified in our case2 always originates from the right coronary sinus and is usually associated with conduction abnormalities and aortic regurgitation. According to its dissecting nature, it can cause congestive heart failure when rupture into the ventricular cavity. Less ruptured noncoronary sinus aneurysms rupture into RA, RV and pericardial cavity. Left SVA typically ruptures into the LV, left atrium (LA) or pericardial cavity is the rarest as demonstrated in our case1.
Clinical features and symptoms are inextricably linked to the aneurysm progression and the location of rupture. An unruptured aneurysm manifest generally clinically silent until it increases in size and compresses nearby structures or develops thromboembolic complications.7SVA rupture is an imperative and serious situation. It can manifest as sudden hemodynamic collapse, acute coronary syndrome, acute heart failure, cardiac tamponade and even sudden death which depends on size of the ruptured orifice, acuity of the rupture and the receiving chamber.8,9In our two cases, embolic events associated with endocarditis also should be taken seriously. Coronary angiography is the gold standard for diagnosing for SVA, however, this is not required in our case. Echocardiography is regarded as the preferred initial examination tool in general. The location, size, and relationship with adjacent structures of dissecting aneurysm, vegetations and any abnormality in the cardiac can be detected by it. Vortex flow in the dissecting cavity, aortic regurgitation, and communication between dissecting cavity and left or right ventricle can be easily showed by color Doppler. The collapse of the aneurysm during systole and blood filled in the aneurysm during diastole, continuous flow in systole and diastole is a useful finding in a ruptured SVA. These features were demonstrated by echocardiography in our two patients.
Subaortic aneurysm, ventricular septal defect, coronary arteriovenous malformation ,fistula and abscess should to be differential diagnosis from SVA. The crucial distinction is that SVA involves one or more sinus(es) of Valsalva structural anomalies in the aortic root. Echocardiographic findings of SVA are crucial for correct diagnosis and early surgical intervention is the optimum treatment for SVA to prevent further rupture and exacerbation of symptoms. According to the authors, the prognosis of the two patients we reported maybe better and the operation is simpler if operation is undertaken in the absence of endocarditis.