Decision Making With Imaging in Asymptomatic Aortic Regurgitation

The authors review the optimal sequence of multimodality imaging studies in patients with chronic asymptomatic aortic regurgitation (AR). The initial questions in evaluating such patients are: 1) is AR severe; and 2) does it significantly impact the left ventricle? Although transthoracic echocardiography is usually able to answer these questions, a cardiovascular magnetic resonance imaging study might be necessary if the data from echocardiography are conflicting or inadequate. If AR is severe and the left ventricle is severely dilated, surgery is indicated. If AR is severe but the left ventricle is not significantly impacted, echocardiographic exercise testing might unmask symptoms. If aortopathy is suspected, cardiovascular magnetic resonance (in younger patients) or computed tomography (in older patients) is necessary. In cases where AR severity or mechanism are unclear and no additional tests are possible, or if there is a potential for aortic valve repair, transesophageal echocardiography is appropriate. Finally, it is good practice to define a follow-up plan with the patient and referring physician, with an explanation as to what can be expected in the future.     

Transcatheter Aortic Valve Replacement for Severe Aortic Regurgitation With Acute Refractory Cardiogenic Shock

From January 2013 to January 2017, 686 consecutive patients were referred to our centre for transcatheter aortic valve replacement, including 5 subjects with severe aortic regurgitation and acute refractory cardiogenic shock. These patients were contraindicated for surgical treatment by the heart team because of high surgical risk (median logistic EuroSCORE: 74.6/Society of Thoracic Surgeons score: 37.9). The success rate of valve implantation was 100% through transfemoral access with self-expandable devices. The observed 30-day mortality rate was 20%. Hence, the transcatheter aortic valve replacement procedure might represent a successful and life-saving intervention for treatment of patients with severe aortic regurgitation who present with acute refractory cardiogenic shock.     

Imaging Modalities in the Diagnosis of Acute Aortic Dissection

The management of patients with acute aortic dissection requires a rapid diagnosis and precise information about the localization and extent of the dissection. Four imaging techniques are currently available to diagnose aortic dissection: aortography; contrast-enhanced computerized tomography (CECT); magnetic resonance imaging (MRI); and transesophageal echocardiography (TEE). All of these techniques have their specific advantages and inherent limitations. Recent studies have demonstrated that MRI may best provide a comprehensive and detailed evaluation of the thoracic aorta, therefore proposing this technique as a "new gold standard" in the diagnosis of acute aortic dissection. TEE, however, may be the best alternative technique, as it combines high sensitivity and specificity with high practicality. The practicality is particularly important in hemodynamically unstable patients in whom a rapid bedside imaging modality is required. CECT might be necessary in selected cases in whom TEE fails to provide a definite diagnosis. Aortography may be necessary in patients in whom clinical signs are suggestive of organ ischemia and in whom coronary anatomy needs to be delineated before operation.     

A Case of Aortic Regurgitation and Hypotension

Takayasu arteritis is a chronic inflammatory large vessel vasculitis affecting the aorta and its main branches. It can present in various forms, and thereby may lead to a delay in diagnosis. We present a patient with Takayasu arteritis, diagnosed at our center when she presented with severe aortic regurgitation. We also review the current knowledge base with respect to Takayasu arteritis.