Reversible myocardial dysfunction and clinical outcome in scuba divers with immersion pulmonary edema

Immersion pulmonary edema in scuba divers is a rare disorder that tends to recur and can be potentially fatal, even in the absence of underlying cardiac disease. Anecdotal cases of reversible myocardial dysfunction have been described in this setting, but little is known of its pathogenesis. The purpose of the present study was to determine the clinical outcomes and the determinants associated with this condition. The data from 54 consecutive divers admitted for acute immersion pulmonary edema during a 5.5-year period were retrospectively studied. A diagnosis of myocardial dysfunction was established by the presence of elevated cardiac troponin T levels, coupled with electrocardiographic changes and/or wall motion abnormalities on the echocardiogram. The demographic, clinical, biologic, and diving characteristics were tested as potential predictors of this disorder. All the patients had complete resolution of symptoms within 72 hours, but 3 required intensive ventilation or hemodynamic support at admission. Reversible myocardial dysfunction was observed in 28% and was associated more with age >50 years (odds ratio [OR] 5.5, 95% confidence interval [CI] 1.5 to 21, p = 0.013), hypertension (OR 8.2, 95% CI 2.1 to 32, p = 0.002), diabetes (OR 22.1, 95% CI 1.1 to 458; p = 0.002), and release of natriuretic peptides (OR 9.1, 95% CI 2.4 to 35, p = 0.001). Follow-up investigations at 1 month were obtained for 49 patients and revealed a significant number of patients with occult hypertension. In conclusion, reversible myocardial dysfunction is not uncommon in divers with immersion pulmonary edema. The short-term overall prognosis is not adversely altered, but severe heart failure with a fatal outcome is unpredictable. Close monitoring of older divers with latent cardiovascular risk factors is warranted.