Ebstein's anomaly. Clinical profile in 174 patients.

The study population consisted of 148 patients who did not undergo surgical treatment and 26 who were operated, most of them diagnosed after the age of 2, with a follow-up from 6 months to 25.3 years. Patients were divided in three groups of clinical deterioration according to their functional class and cardiothoracic index (CTR) long-term follow-up in 148 nonoperated patients showed significant differences for mortality between groups I and III (p < 0.001), and between groups II and III (p < 0.02). Predictors of death included the association among functional class III or IV CTR > or = 65% with either cyanosis or arrhythmias (p < 0.05). The multivariate analysis showed that clinical deterioration (p < 0.0001), CTR (p < 0.0002) and functional class (p < 0.001), were significant for mortality. Kaplan-Meier analysis showed a survival rate of 81% in the overall patients free from surgical treatment. According to Kaplan-Meier analysis, the rate of survival was lower in patients with CTR > or = 65% (63.5%), in patients who had functional class IV (52.5%) and in patients included in group III of clinical deterioration (38.2%). Despite the fact that the association of functional class III or IV plus CTR > or = 65% with either cyanosis or arrhythmias is a good predictor for death, the mortality in patients who had only one of these variables was lower. Patients included in group II of clinical deterioration in stable condition presented long survival with medical treatment. Due to the high mortality rate found in group III, surgical treatment of Ebstein's anomaly must be done before deteriorating into group III. Surgical indication must be done considering the surgical risk of each group according to the experience of the Institution and comparing the rate of surgical mortality with the rate of survival without surgery.