Indirect signs of aortic dissection on POC-TTE despite an ADD-RS of 0 and D-dimer < 500 ng/mL

Abstract

Aortic dissection (AD) is a "can't miss" diagnosis for emergency physicians. An algorithm combining the Aortic Dissection Detection Risk Score (ADD-RS) with D-dimer has been proposed as a high-sensitivity clinical decision tool for AD that can determine the need for advanced imaging. Here we present a case of a 48-year-old male who presented to the emergency department (ED) with chest pain and dyspnea. He had an ADD-RS score of 0 and negative D-dimer, which placed him in the low-risk category not requiring further advanced imaging. Despite this, he was found to have a pericardial effusion and dilated aortic root on point-of-care transthoracic echocardiogram (POC-TTE). These findings increased suspicion for AD and prompted the emergency physician to order a computed tomography angiography (CTA), revealing a thoracic AD. The patient successfully underwent surgical repair. This case demonstrates that the ADD-RS + D-dimer algorithm would have erroneously ruled out AD, without the inclusion of indirect findings of AD from the POC-TTE. This highlights the value of using POC-TTE as an adjunct to the ADD-RS + D-dimer algorithm in the diagnostic evaluation of AD and how giving more weight to indirect signs of AD on POC-TTE could potentially increase the sensitivity of the combined ADD-RS + D-dimer + POC-TTE algorithm.

Keywords: ADD-RS; Aortic dissection; Case report; D-dimer; Diagnosis; POC-TTE; Point-of-care ultrasound.