Egg and banana sign: a new diagnostic ct marker for pulmonary hypertension

Abstract

Abstract: 

There is often a two-year delay in the diagnosis of Pulmonary Hypertension (PH) because the initial symptoms (dyspnoea and fatigue) are frequently attributed to other comorbidities. In addition, it is diagnosed by an invasive technique:  right heart catheterization  (RHC), responsible for the appearance of adverse events such as arrhythmias, hypotension and pneumothorax, among others. Non-invasive tests are playing an important role in early detection. A tomographic marker, the egg and banana sign (EBS) was recently introduced, which could contribute to the diagnosis. 

Objectives: To determine if EBS is a sensitive and specific diagnostic marker for PH. To re-evaluate the correlation between the principal diameter of the pulmonary artery (PA) and the pulmonary artery-ascending aorta ratio (PA-Ao ratio) both individually and in combination with EBS. 

A total of 42 patients were evaluated who, between 2017 and 2021, underwent RHC and CT that included the aortic arch. Two blind observers determined whether EBS was present or absent on CT scans. Qualitative data were described using absolute and relative frequencies, ROC curves. The Chi Square test was performed for the association between variables. P <0.05 was considered statistically significant. The work was approved by the Departamento de Investigación y Docencia del Hospital Italiano de Córdoba.

Of the total number of patients, 19 had PH and 23 were control subjects. 75% of the patients in whom EBS was observed had PH with an average mPAP of 39 mmHg (Sensitivity: 62%; Specificity: 88.24%; P: 0.036). Regarding the PA, EBS was observed in patients with a diameter greater than 32 mm, with an average of 40mm. (Sensitivity: 75%; Specificity: 82%; p = 0.0001). Of the patients with PH, 74% had a PA-Ao ratio greater than 1 (p: 0.0034). 

Conclusion:  in our population EBS presented a high specificity for mPAP from 39 mmHg. In association with the diameter of the PA, the classic marker, both its sensitivity and specificity were high.