Abstract: Objective To analyse the misdiagnosis reason of cardiac pleural effusion.Methods To analyse clinical symptoms of 14 cases with cardiac pleural effusion retrospectively.Results (1)The patients over 45 years old were 86%,whose average age was 59.4 years.(2)71% of cases had paroxysmal dyspnea at night, enlarged heart, enlarged liver with tenderness, edema with legs and feet.57% of cases had heart failure symptoms and signs such as vena jugular enlargement.(3)All of cases had ST-T change and showed lack of blood and cardiac muscles hurt in electrocardiogram,71% of cases had cardiac arrhythmia.(4)All of cases showed different edema image of lung interstitial or/and alveolar in chest X-ray and CT.71% of cases had cardiac image enlargement,93% of cases had two lateral pleural effusion. 92% of cases of cell members were not typical pleural effusion.(5)Clinical diagnosis: 8 of 14 cases were coronary atherosclerotic heart disease.One case with pericarditis,three cases with hypertension.), two of cardiomyopathy disease, two of pulmonary heart disease,one of hyperthyroidism heart disease,one of hypertension heart disease. There were 14 cases of pneumonia and congestive heart failure.Conclusion Cardiac pleural effusion was found in the middle age and old age patients commonly. All of them combined with some basic diseases which could lead to heart failure. Many diseases consist at the same time, impact each other, cover or lead to more serious heart symptoms and signs, effect the examination result of pleural effusion, which make the diagnosis more difficult. Serious clinical observation and analysis of the disease history and clinical imformation could prevent from misdiagnosis.

Key words: Pleural effusion, heart failure, misdiagnosis