Delay and misdiagnosis in sub-massive and non-massive acute pulmonary embolism

There is limited information about the extent and clinical importance of the delay in the diagnosis of acute pulmonary embolism.

Between 1998 and 2009, all consecutive patients diagnosed of acute pulmonary embolism from a registry of a single department were evaluated. We recorded the start or shift in symptoms as the beginning of pulmonary embolism and the mistaken diagnosis for which the patients had been treated. We evaluated the factors associated with the delay and misdiagnosis and their relation with mortality.

Overall 375 patients were evaluated. Median age was 75 years, interquartile range (IQR) 15, and female 186 (49%). Median delay was 6 (IQR 12) days. Median Wells score was 4.5 (IQR 3). Delay in diagnosis was longer than 6 days in 50% (95% CI 44-55) of patients, longer than 14 days in 25% (95% CI 21-30) and longer than 21 days in 10% (95% CI 7-13). Misdiagnosis occurred in 50% (95% CI 44-55) of patients. Higher age, more days of delay and the absence of syncope or sudden onset dyspnea were factors associated with misdiagnosis. Follow-up was carried out in 331 patients during a median of 31 (IQR 45) months. 36% (95% CI 33-43) of patients died [median 8 (IQR 29) months]. Higher age, misdiagnosis and a history of cancer were factors associated with mortality. Days of delay were not associated with mortality.

Delay and misdiagnosis of pulmonary embolism is frequent. Elderly patients and the absence of syncope or sudden onset dyspnea favour the misdiagnosis. Delay in diagnosis does not participate in mortality.