Statistics from Altmetric.com
It is generally believed that unruptured aneurysms of the sinus of Valsalva do not cause symptoms. They often remain undiagnosed unless rupture occurs. However, it is now recognised that unruptured aneurysms can cause symptomatic haemodynamic compromise, arrhythmias, or conduction disturbances. We describe a patient whose unruptured aneurysm caused right ventricular outflow obstruction.
In 1990 a 61 year old man experienced syncope after a considerable intake of alcohol. The patient presented to the outpatient department and a systolic heart murmur was heard. Cardiac auscultation showed a grade II/IV early systolic murmur along the left parasternal border. Echocardiography showed an aneurysmal sac originating at the sinus of Valsalva protruding into the right ventricular outflow tract. A peak Doppler flow velocity of 1.4 m/s was measured at the right ventricular outflow tract. During cardiac catheterisation, the right ventricular pressure was normal—a gradient of 5 mm Hg was measured between the right ventricular cavity and the pulmonary artery. Oxygen saturation measurements gave no evidence of an intracardiac shunt. Angiography did not show any significant coronary abnormalities. Ascending aortography demonstrated a large aneurysm originating from the right coronary cusp (fig 1). Owing to the lack of symptoms, the patient was managed conservatively.
Five years later, the patient underwent an uneventful nephrectomy for a Grawitz tumour. One year later he was readmitted because of progressive exertional chest pain, fatigue, and dyspnoea. Transoesophageal echocardiography showed significant enlargement of the aneurysm with appearance of spontaneous contrast. There was a systolic gradient of 41 mm Hg at the right ventricular outflow tract during cardiac catheterisation; intracardiac shunting was excluded by oxygen saturation measurements. Coronary angiography showed a normal left coronary artery and collateral filling of the right coronary artery. The neck of the aneurysm incorporated the ostium of the right coronary artery, which could not selectively be catheterised. Aortography showed that the aneurysm had significantly enlarged; there was extremely slow contrast washout from the aneurysm (fig 2). Surgical resection of the aneurysm was planned. Preoperative chest radiography showed multiple coin lesions, interpreted as lung metastases originating from the Grawitz tumour. Owing to the poor prognosis, the operation was cancelled.
Most aneuryms of the sinus of Valsalva originate from the right cusp. There is a male predominance and an association with ventricular septal defect, aortic regurgitation, pulmonic stenosis, and membranous subaortic stenosis.1 These aneurysms are considered to be either congenital or caused by syphilis, bacterial endocarditis, atherosclerosis or aortic dissection. The cause of the congenital form is thought to result from a defect in the continuity of the aortic media and the valve ring tissue. Unruptured aneurysms of the right coronary cusp may cause right ventricular outflow tract obstruction, pulmonary insufficiency, obstruction or thrombotic occlusion of the ostium of the right coronary artery.2-4 Tricuspid stenosis, conduction abnormalities owing to AV node injury, and tricuspid insufficiency are reported in association with aneurysms of the non-coronary cusp.5 The rare aneurysm of the left coronary cusp may compress the left coronary artery and cause severe coronary insufficiency.
In our case, the aneurysm significantly enlarged over six years, resulting in right ventricular outflow tract obstruction and insufficiency of the right coronary artery; therefore, we recommend regular non-invasive assessment.