A Case of Right Sinus of Valsalva Rupture with Dissection into Interventricular Septum Causing Left Ventricular Outflow Tract Obstruction
Fifty-four-year-old female visited outpatient clinic due to the worsening dyspnea experienced in the past month. Recently, she felt shortness of breath even during short distance walking. She also complained of intermittent coughing for the previous 6 months. She was diagnosed with essential hypertension 2 years ago, and has been taking single antihypertensive medication. She did not recall any other medical conditions which can explain her symptoms.\nOn her hospital visit, her blood pressure was 122/68 mm Hg, heart rate 95 beats per minute and respiration rate of 22 per minute. Physical examination was not remarkable except for loud to-and-fro murmurs which were audible along the left sternal border. Breathing sound was clear in both lung fields. The chest radiograph showed slight increases in cardiothoracic ratio without signs of pulmonary congestions. The electrocardiogram showed sinus rhythm with QRS configuration of right bundle branch block.\nInitial laboratory studies revealed elevated levels of brain natriuretic peptide to 699 pg/mL, but the levels of cardiac markers including cardiac troponin and creatine kinase-MB isoenzyme were within normal limits. Routine blood cell counts and chemistry tests were also normal.\nOn transthoracic echocardiographic exam (TTE), basal part of interventricular septum was dissected by intrusion of a cystic cavity which communicated with coronary sinus of Valsalva. The cystic structure appeared in various sizes according to the cardiac cycle, increasing during diastole with protrusion into LVOT () and decreasing during systole (). Transesophageal echocardiogram (TEE) also showed dynamic changes of the cystic structure with inflows () and outflows () between the aortic root and the cavity. However, no shunt flow was observed between left and right heart. Although the size of the protruding cavity decreased during systole, the hemodynamic obstruction of LVOT was recognized by Doppler echocardiography with peak pressure gradients of 55 mm Hg (). Additionally, aortic regurgitant flow of moderate degree was visible during diastole on both the TTE and TEE.\nFor further evaluations of the anatomical relationship between the SVA and surrounding structures, the cardiac multi-detector computed tomogram (MDCT) was performed. MDCT clearly demonstrated the main part of the SVA extending from the right coronary sinus (). Interventricular septal dissection and cyst-shaped aneurysm throughout the cardiac cycle was best visualized through the scans ().\nBecause of the disabling symptoms along with serious anatomic and hemodynamic deteriorations, clinical decision was made to offer prompt surgical corrections for the patient. Therefore, repair of interventricular septal dissection with concomitant aortic valve replacement was conducted. Right coronary cusp was also shortened and diminished. Replacement of aortic valve through aortotomy was performed with 20 mm ATS mechanical aortic valve prosthesis (Medtronic Inc., Minneapolis, MN, USA). Histologic examination of the tissues revealed chronic degenerative changes (). There were no evidences of chronic or acute inflammations or infiltrative disorders. The patient was discharged uneventfully 9 days after surgery, and did not have any complaints for 3 months thereafter.