Year : 2013 | Volume
: 16 | Issue : 3 | Page : 225--226
False diagnosis of acute Type A dissection
Praveen Kerala Varma, Madathipatt Unnikrishnan Menon
Department of Cardio Thoracic and Vascular Surgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
Praveen Kerala Varma
Division of Cardiac Surgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum - 695 011, Kerala
|How to cite this article:|
Varma PK, Menon MU. False diagnosis of acute Type A dissection.Ann Card Anaesth 2013;16:225-226
|How to cite this URL:|
Varma PK, Menon MU. False diagnosis of acute Type A dissection. Ann Card Anaesth [serial online] 2013 [cited 2020 Sep 24 ];16:225-226
Available from: http://www.annals.in/text.asp?2013/16/3/225/114245
We read with interest the article by Baloria et al.,  describing a false diagnosis of acute Type A dissection by computerized tomography angiogram (CTA), which resulted in patient undergoing an unnecessary sternotomy. We wish to describe a similar experience that happened in one of our patient in year 2003.
A 32-year-old man with no prior co-morbidity was admitted in our coronary care unit with severe retrosternal chest pain. Chest X-ray was unremarkable, cardiac enzymes were not elevated and other routine investigations were within normal limits. He underwent CTA that showed a posterior flap near the aortic root. However, rest of ascending aorta and arch were free of flap. A diagnosis of localized Type A aortic dissection was made and he was prepared for ascending aortic replacement. Transesophageal echocardiography (TEE) was not available at that time. After sternotomy and pericardial marsupialization, ascending aorta and aortic root looked normal. This created a diagnostic dilemma. However, we cannulated, went on cardiopulmonary bypass, cross clamped the aorta, administered cardioplegia and opened the aorta. There was no dissection flap in the aortic root; however, he had very prominent sinotubular ridge and aortic sinuses with a normal tri-leaflet valve. Aortomy was closed. The CTA was reviewed with our radiologist who opined that probably the prominent sinotubular ridge and sinuses may have lead to false appearance of flap. Patient made uneventful recovery.
Acute pericarditis as reported by the authors, acute pulmonary embolism and esophageal pathologies like diffuse esophageal spasm may mimic the presentation of acute Type A dissection. In a stable patient with unusual finding like a posterior flap in CTA should raise the suspicion of false diagnosis of acute dissection. As pointed out in the editorial  TEE has the highest sensitivity and specificity among the imaging tools. However, diagnostic problems may be encountered in the ascending aorta where reverberation artifacts can result in false positive diagnosis of dissection. Principal limitations of TEE are its dependence on a high degree of operator skills and blind areas in the distal ascending aorta and proximal transverse arch which are obscured by the air-containing trachea and left main bronchus. Even though conventional CTA has only around 90% specificity, multi-detector computed tomography (MDCT) have reported sensitivities and specificities of 100%. The multi-detector arrays in MDCT allow accurate imaging of a large anatomic area with high resolution and a short acquisition time. Triple-rule-out CT protocols are increasingly being used by several institutions where pulmonary and coronary arteries and aorta can be evaluated in a single examination and these advances may hopefully limit the incidence of false diagnosis of acute Type A dissection.
|1||Baloria KA, Dhir A, Pillai B, Selot N. Aortic dissection: To be or not to be? Ann Card Anaesth 2013;16:126-8.|
|2||Neema PK. Acute aortic dissection: Pitfalls in the diagnosis. Ann Card Anaesth 2013;16:83-5.|