Unknown incidence, isolated right ventricular thrombus is a very uncommon disorder. It has frequently been claimed to be linked to right ventricular infarction, deep vein thrombosis, or pulmonary embolism. There have been cases of severe chronic obstructive pulmonary disease and profound hypoxia, which may lead to right ventricular dysfunction and thrombus in the isolated right ventricle. An 80-year-old man with acute respiratory failure was hospitalized to our emergency room. He also had Alzheimer's, COPD, diabetes mellitus, and atherosclerotic heart disease. The patient wasn't consistently using his prescription drugs and oxygen therapy. His lungs were examined, and wheezing or a drawn-out expiration was found. S1 and S2 were normal on cardiac auscultation, and there was no S3, S4, or murmur. Similar to earlier ECGs, the electrocardiogram displayed T wave inversion in leads V1-V5 and D2-D3-AVF. No pulmonary embolism was observed with computed tomography. A 1.5x2.8 cm mass was discovered between the right ventricular trabeculae during routine echocardiography, which was used to assess heart function. Moreover, there was middle tricuspid regurgitation, right ventricular dilatation, and an 8 mm tricuspid annular plane systolic extension (TAPSE). To make the diagnosis clearer, cardiac magnetic resonance imaging was carried out. Nodular forms between the trabeculations in the right ventricle were seen using cardiac resonance imaging and were considered to be thrombi because they appeared hypointense on late contrast images. Treatment with apixaban and an inhaler were both initiated. A control examination was scheduled for the patient. Transthoracic echocardiography, transesophageal echocardiography, and cardiac magnetic resonance imaging can all identify RV thrombus. Although transthoracic surgery is the procedure of choice in clinical practice, right ventricular thrombus diagnosis is not usually as straightforward as left ventricular thrombus diagnosis. According to recent studies, the most precise method for detecting myocardial thrombus is cardiac MRI. While being more expensive than transthoracic echocardiography, cardiac MRI can be utilized to differentiate between different types of heart masses or to rule out fatal conditions such right ventricular thrombus.