EComment. Re: Is cardiac magnetic resonance imaging as accurate as echocardiography in the assessment of aortic valve stenosis?

Abstract

Aortic stenosis (AS) is the most frequent degenerative valvular heart disease in Western countries and its prevalence increases with an ageing population [1]. Interestingly, Wong and colleagues [2] have analysed a very common clinical scenario of a 72-year old man with an incidental diagnosis of AS on routine transthoracic echocardiography to answer the question: “Is cardiac magnetic resonance (CMR) imaging as accurate as echocardiography in the assessment of aortic valve stenosis?” They selected and level-headedly examine 12 out of more than 200 papers to reach the answer and they conclude that CMR is as accurate as echocardiography in the evaluation of patients with aortic valve stenosis, and that CMR has better interand intraobserver reliability and demonstrates an advantage over echocardiography in the detection of severe AS with greater specificity and sensitivity. It must also be emphasized that dobutamine stress echocardiography may help to differentiate between severe AS and pseudo severe AS and to assess the presence of LV contractile or flow reserve, which has been associated with better prognosis in patients undergoing surgical aortic valve replacement [3]. The advent of new echocardiographic techniques, such as speckle tracking echocardiography has also enabled the detection of eventually associated early myocardial damage in the left ventricle and have a good correlations with the extent of myocardial scar assessed found at MR late gadolinium enhancement (LGE) [4]. The contrast enhanced CMR with the LGE evaluation or better still, the new technique of T1 mapping could evidence the presence of scar, replacement focal fibrosis or interstitial diffuse fibrosis that are associated with worse prognosis [5]. Overall, the final conclusion of the authors that “the final choice, however, is as likely to be influenced by the availability of magnetic resonance imaging and expertise in interpreting the results as on accuracy and reliability” clearly represent the everyday real-life scenario.