SVA is a rare cardiac abnormality. It is mainly due to congenital dysplasia of the aortic sinus wall, which lacks elastic fibers and smooth muscle tissue in the middle layer. Under the action of aortic high-pressure blood flow, the sinus wall gradually expands and thins to the adjacent cardiac cavity to form a sinus tumor. In addition to innate factors, it can also be secondary to infections (syphilis, bacterial endocarditis, tuberculosis), trauma, or connective tissue diseases that affect the aortic wall [2]. SVA is prone to be associated with other cardiac malformations, the most common of which are ventricular septal defects, bicuspid aortic valve malformations, and aortic regurgitation [3].
SVA mostly occurs in the right coronary sinus, accounting for more than 75%, followed by the non-coronary sinus, accounting for about 15%, and rarely occurs in the left coronary sinus, which is related to the asymmetric distribution of stress on the three aortic sinuses [4]. Due to the relationship of anatomy, the right coronary SVA is usually adjacent to the right ventricular outflow tract and often breaks into the right ventricle or right atrium, while the no coronary SVA often breaks into the right atrium [5]. Our report of the left coronary SVA invading the ventricular septum is extremely rare.
The hemodynamic changes caused by the ruptured SVA depend on the size and the compartments at both ends of the rupture. In general, the larger the rupture, the greater the shunt volume. When SVA breaks into the right ventricle or the right ventricular outflow tract, the right ventricular pressure is significantly lower than the aortic pressure in the diastole, and the left to right shunt occurs in the whole cardiac cycle, which is mainly in the diastole; When SVA breaks into the right atrium, the left to right shunt occurs in the whole cardiac cycle due to the low pressure of the right atrium. A large number of shunts cause an increase in the volume load of the right and left ventricles, a compensatory enlargement of the cardiac cavity, and compensatory hypertrophy of the ventricular wall, which can eventually lead to heart failure and pulmonary hypertension; The hemodynamic changes caused by a small amount of shunt were not obvious.
SVA is usually asymptomatic when they are not ruptured. Chest pain, palpitations, shortness of breath, and coughing may occur when the sinus tumor ruptures. During the physical examination, continuous murmurs of the whole cardiac cycle could be heard in the auscultation area of the parasternal aorta [6]. In our report, the electrocardiogram suggested a complete right bundle branch block, which is consistent with the report of Choudhary et al.[7] who reviewed 26 cases of SVA dissecting into the interventricular septum.
Echocardiography is currently recognized as the preferred method for diagnosing ruptured SVA with high accuracy. Especially, the appearance of TEE can provide more information due to its high resolution, which makes it very valuable for the identification, localization, and differential diagnosis of ruptured aneurysms of the sinus of Valsalva[8].
The life expectancy of patients with successful SVA repair is close to that of healthy people, with a 10-year survival rate of 90%-95% [9]. The need for intervention in the unruptured SVA is controversial. When complications such as outflow tract obstruction, arrhythmia, or infection occur, surgical repair is required.