Discussion
To our knowledge, this is the first publication of subtle aortic dissection with a supraannular aortic root intimal tear in a patient with a dilated aortic root and undiagnosed bicuspid aortic valve that necessitated treatment with a Bentall procedure. This young lady developed acute severe AR and pulmonary oedema due to subtle aortic dissection. However, the patient was initially misdiagnosed and treated for a lower respiratory tract infection. Prior to presenting to her local hospital, she suffered an episode of tight central chest pain and this is likely to be the event when she potentially developed subtle aortic dissection but, despite two CT aortograms, no dissection was detected.
Svensson et al. reported that 9 out of 181 patients who underwent ascending or aortic arch repair had an undiagnosed aortic intimal tear without hematoma [4]. In all patients, this specific variant of aortic dissection characterized with a stellate or linear intimal tear was not proven by multiple noninvasive imaging techniques and diagnosis was made intraoperatively [4]. They also found that a subtle eccentric bulge or bubble was detected on aortography in 6 out of 9 patients which suggested that aortography should be considered if the more subtle form of aortic dissection is suspected based on clinical presentation. Furthermore, the authors reported that if multimodality imaging tests fail to detect aortic dissection and an ascending aortic aneurysm >4.5 cm in diameter is measured, particularly if the patient has Marfan syndrome, Ehlers-Danlos syndrome, or a pericardial effusion, then an invasive imaging test such as aortography should be performed [4]. However, our patient had the suspicion of non-infective or infective endocarditis due to the suggestion of a small echogenic mass with the acute severe AR on TTE and had a bicuspid AV with a supraannular intimal tear found at the time of surgery.Wang et al. have described a patient with an annular intimal tear of the aortic root that was misdiagnosed as AR [5]. Similarly, preoperative imaging was inadequate for correct diagnosis which was confirmed intraoperatively. However, their patient underwent successful repair of the aortic root tear with Teflon felt, as the aortic root was not dilated. On the other hand, Shingal et al. have reported a patient that developed aortic intimal tear with severe AR secondary to subadventitial rupture of ascending aorta and no signs of dissection flap who underwent a Bentall procedure, but in their case it was a result of blunt trauma [6]. Manuchehry et al. have reported a case of fatal cardiac tamponade caused by a limited aortic dissection variant that was not detected by multiple imaging modalities [7]. However, their patient had the diagnosis confirmed during an autopsy.