Patients with intermediate-risk pulmonary embolism (PE) comprise a significant patient population. Computerized tomographic pulmonary angiography (CTPA) plays a crucial role in diagnosis and determining the prognosis. Right ventricular diameter/left ventricular diameter (RVD/LVD) ratio measured through CTPA provides insight into right ventricular overload. The aim of the present study was to determine the role of RVD/LVD ratio on decision of treatment between high and low intermediate-risk PE. A retrospective observational study was conducted between May 2018 and May 2022 on patients with intermediate-risk PE at the Emergency Department (ED) of a tertiary care hospital. The demographic information, risk factors, vital signs at presentation, laboratory data, CTPA images and treatment modality of the patients were obtained. RVD/LVD was calculated from the CTPA images. All-cause mortality at 24 h, 7 and 30 days were recorded. A total of 127 patients were included. In total, 52 (40.9%) patients were in the low-intermediate risk group, and 75 (59.1%) patients were in the intermediate-high risk group. A total of 54 patients were administered thrombolytic therapy while 73 patients were not. The mean RVD/LVD was 1.35±0.25 in patients who were administered thrombolytic therapy and 1.17±0.34 in those who were not. A significant association was identified between RVD/LVD and the administration of thrombolytic therapy (P<
0.001). RVD/LVD and mortality were not significantly correlated (P=0.248). No significant association was found between the administration of thrombolytic therapy and mortality (P=0.569). RVD/LVD assessed through CTPA was found to be significantly decisive for administering thrombolytic therapy but not significantly predictive for mortality in intermediate-risk patients with PE presenting to the ED.