ATYPICAL PRESENTATIONS AND ECHOCARDIOGRAPHIC FINDINGS IN PATIENTS WITH CARDIAC-TAMPONADE OCCURRING EARLY AND LATE AFTER CARDIAC-SURGERY

Cardiac tamponade, a potentially lethal complication following cardiac surgery, may present either early or late postoperatively and may be difficult to diagnose due to atypical clinical, hemodynamic, or echoca rdiographic findings. To determine the frequency and clinical features of postoperative cardiac tamponade, we performed a review of 510 cons ecutive patients who underwent cardiac surgery. The incidence of posto perative cardiac tamponade was 2.0 percent (10/510 patients) and occur red following valvular, bypass, and aortic surgery. Nine of ten patien ts had either atypical clinical, hemodynamic, and/or echocardiographic findings. The diagnosis of tamponade was made 1 to 30 days (mean=8.5 days) postoperatively. Presenting symptoms were often mild and nonspec ific. Classic signs including hypotension, pulsus paradoxus greater th an 12 mm Hg, and elevated jugular venous pressure were present in 7, 6 , and 5 patients, respectively. Right heart hemodynamics revealed elev ated and equalized diastolic pressures in three of six patients. Two-d imensional echocardiography revealed selective compression of the left ventricle (LV) (four patients), right ventricle (RV) (one patient), l eft atrium (LA)/RV (one patient), LA/LV (one patient), LA/LV/RV (one p atient), all four chambers (one patient), and no diastolic collapse of any chamber (one patient). There was often an absence of anterior per icardial fluid (six patients) with tethering of a portion of the RV to the chest wall anteriorly (five patients). Coagulation parameters wer e ''supratherapeutic'' in only three of eight patients who were receiv ing systemic anticoagulants at the time of diagnosis. The initial diag nosis was confused with congestive heart failure in one patient, pulmo nary embolism in three patients, acute myocardial infarction in two pa tients, and sepsis in one patient. Fight of ten patients survived; all of these patients underwent surgical removal of fluid and/or hematoma in the operating room. We conclude that postoperative tamponade after cardiac surgery may have varied clinical and hemodynamic presentation s, often due to selective chamber compression by loculated fluid or cl ot. Due to its frequently atypical features and presentation that may simulate other disorders, the diagnosis of tamponade should be conside red whenever hemodynamic deterioration or signs of low output failure occur in the postcardiotomy patient.