Data Availability StatementAll data analyzed was included in this published case report. be given much more attention to make accurate diagnosis and appropriate interventions. strong class=”kwd-title” Keywords: Paradoxical embolism, Pulmonary embolism, Renal artery embolism, Breast cancer, Surgery Background Paradoxical embolism (PDE) first proposed by Cohnheim in 1877, referring to the passage of venous or right-sided cardiac thrombus into the arterial or systemic circulation, is comparatively rare EBE-A22 and represents less than 2% of all instances of systemic arterial emboli . In general, the most common PDE sites are extremities (49%) and cerebrum (37%), where only 23% of PDE had two definable embolic sites and 10% had three . Renal artery is infrequent and renal artery embolism (RAE) is typically seen on patient with atrial fibrillation or other cardiovascular disease . It has been accepted that patent foramen ovale (PFO) or intracardiac defect working as a significant abnormal passage has played a crucial role in this process. However, in contrast to the accepted EBE-A22 fact, the patient of this case without any indicator of most common risks still experienced concomitant PE and RAE after breast-conserving therapy. Case presentation A 55-year-old woman with BMI 24.6?kg/m2 diagnosed with invasive ductal carcinoma of right breast (cT2N0M0) was suddenly fainted with profuse sweating and followed developing severe gastrointestinal discomfort when she got up to walk in ward 12?h after lumpectomy, but no progressive chest pain, cough or unconsciousness was observed. Subsequently, she felt mild shortness of breath and dull pain on the right flank as well as lower right abdomen, accompanying vomiting and diarrhea in the next 30?min. Under this emergency circumstance, she was performed with some verification and physical lab examinations. Electrocardiogram monitor recognized a mild loss of bloodstream air saturation which ranged from 82 to 89% with 4?L of 100% air inhalation through nose cannula, blood pressure dropping to 88/57?mmHg, respiratory rate of 24/min, heart rate of 92 beats/minute with normal sinus rhythm. Apparent abdominal tenderness, rebound tenderness or abnormal auscultation findings was not detected on physical examination. The level of blood glucose was measured of 9.4?mmol/L. Brain natriuretic peptide did not indicate heart failure. Meanwhile, the value of myocardium enzymes including CK, CK-MB EBE-A22 and cTnI were normal. D-dimmer level was slightly increased to 1.2?g/ml (normal, ?1.0?g/ml). The arterial blood gas EBE-A22 analysis indicated: pH, 7.39; PaCO2, 42.9?mmHg; and PaO2, EBE-A22 65?mmHg. Additionally, routine urinalysis showed occult blood positive (+++) and microscopic haematuria was 120RBC/ul. Under 1000?ml liquid transfusion, there was still no any amelioration in her blood pressure and hypoxemia. After exclusion of hypoglycemia and acute myocardial infarction, the diagnosis of PE was highly suspected. Thromboembolism was evidenced in the main bilateral branches of pulmonary trunk and right renal artery (Fig.?1) after urgent MDCT of chest and abdomen. The final diagnosis was paradoxical embolism presented with concomitant pulmonary embolism (PE) and renal artery embolism (RAE). She was subsequently transferred to ICU and administered with anticoagulant therapy by low molecular weight heparin (LMWH, 4200?IU bolus) intravenously, followed by subcutaneously injection of LMWH (6000?IU) every 12?h upon the advice of multi-disciplinary team. Meanwhile, further examinations to unveil the cause of disease excluded the potential of antiphospholipid antibody syndrome (APAS), systemic vasculitis and other autoimmune diseases. Echocardiography showed no presence of PFO or intracardiac defect (Fig.?2), and no deep venous thrombus (DVT) of bilateral lower extremities was identified by ultrasound either. After 7?days of treatment with LMWH, most previous invisible thrombus could not be detected any more in the repeated MDCT scan (Fig.?3). Ultimately, she was discharged in good condition after 10?days therapy and advised to continuously take rivaroxaban for 3?months. During 3?months following up, she was doing well without any special complaint. Open in a separate window Fig. 1 Contrast-enhanced CT angiography demonstrated a filling defect of main bilateral branches of pulmonary trunk (a and b), and an absent enhancement of a segment of right renal parenchyma in the upper pole (c and d). Ill-defined border and perinephric stranding suggested renal artery embolism was acute Open in a separate window Fig. 2 On the first day after paradoxical embolism event, the color doppler echocardiography revealed that POLDS there was no patent foramen ovale existence (a) or intracardiac defect except that the superior ventricular septum had a mild hypertrophy (15?mm) (b) Open in a separate window Fig. 3.