Prevalence and prognostic value of acute cor pulmonale and patent foramen ovale in ventilated patients with early acute respiratory distress syndrome: a multicenter study.

PURPOSE: We sought to determine the prevalence of and factors associated with acute cor pulmonale (ACP) and patent foramen ovale (PFO) at the early phase of acute respiratory distress syndrome (ARDS), and to assess their relation with mortality.
METHODS: In this prospective multicenter study, 200 patients submitted to protective ventilation for early moderate to severe ARDS [PaO₂/F(I)O₂: 115 ± 39 with F(I)O₂: 1; positive end-expiratory pressure (PEEP): 10.6 ± 3.1 cmH2O] underwent transthoracic (TTE) and transesophageal echocardiography (TEE) <48 h after admission. Echocardiograms were independently interpreted by two experts. Factors associated with ACP, PFO, and 28-day mortality were identified using multivariate regression analysis.
RESULTS: TEE depicted ACP in 45/200 patients [22.5%; 95% confidence interval (CI) 16.9-28.9%], PFO in 31 patients (15.5%; 95% CI 10.8-21.3%), and both ACP and PFO in 9 patients (4.5%; 95% CI 2.1-8.4%). PFO shunting was small and intermittent in 27 patients, moderate and consistent in 4 patients, and large or extensive in no instances. PaCO₂ >60 mmHg was strongly associated with ACP [odds ratio (OR) 3.70; 95% CI 1.32-10.38; p = 0.01]. No factor was independently associated with PFO, with only a trend for age (OR 2.07; 95% CI 0.91-4.72; p = 0.08). Twenty-eight-day mortality was 23%. Plateau pressure (OR 1.15; 95% CI 1.05-1.26; p < 0.01) and air leaks (OR 5.48; 95% CI 1.30-22.99; p = 0.02), but neither ACP nor PFO, were independently associated with outcome.
CONCLUSIONS: TEE screening allowed identification of ACP in one-fourth of patients submitted to protective ventilation for early moderate to severe ARDS. PFO shunting was less frequent and never large or extensive. ACP and PFO were not related to outcome.