Pulmonary embolism after cardiac surgery.

Objectives: We examined the incidence of pulmonary embolism after cardiac surgery.

Background: Because venous thromboembolism is considered to be an uncommon complication after cardiac surgery, its incidence was documented in a consecutive series of 1,033 patients who underwent cardiac surgery over a 5-year period.

Methods: Parallel cohorts of patients in a tertiary referral center were evaluated and the incidence of pulmonary embolism was compared in subgroups of patients undergoing coronary bypass surgery, valve surgery and combined procedures.

Results: Pulmonary embolism developed in 33 (3.2%) of the 1,033 cardiac surgical patients, within 2 weeks of a coronary bypass operation in most; it did not develop in any patient who had isolated valve replacement surgery (p < 0.05). The diagnosis of pulmonary embolism was established by pulmonary angiography in 24 patients, ventilation/perfusion lung scan in 3, postmortem examination in 5 and clinical examination in 1 patient. Important risk factors for pulmonary embolism included prolonged postoperative recovery, obesity and hyperlipidemia. The mortality rate was 18.7% in patients with in contrast to 3.3% in those without pulmonary embolism (p < 0.01).

Conclusions: Although pulmonary embolism is rare after isolated valve replacement, it is not an uncommon complication after coronary bypass surgery.