Correlates of syncope in patients with acute pulmonary thromboembolism.

Identification of pulmonary thromboembolism (PTE), as a cause of syncope, is important and may be life saving. We prospectively analyzed data on 335 patients with acute PTE. Relationships between syncope secondary to acute PTE and clinical findings, risk factors, and imaging modalities were analyzed. Of the 335 patients, 36 (10.7%) had syncope at presentation. Compared to patients without syncope, those with syncope had a higher frequency of right ventricular (RV) dysfunction (94.3% vs 72.1%, respectively; P value = .004) and saddle embolism (24.2% vs 10.9%, respectively; P value = .044). Frequency of RV dysfunction was similar between patients with and without saddle embolism. Although not significant, more patients with syncope had a history of previous PTE (P value = .086). By multivariable analysis, RV dysfunction and saddle embolism were independent correlates of syncope in patients with PTE. In-hospital mortality was not significantly different between the groups. In conclusion, among patients with PTE, RV dysfunction and saddle embolism were the independent correlates of syncope.