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OBJECTIVE:To evaluate the viability of a probabilistic record linkage strategy to identify deaths of patients who underwent complex cardiology procedures among the total deceased population. METHODS:The processing cost was estimated based on 1,672 records of patients undergoing coronary artery bypass grafting that were compared with all death records in Brazil in 2005. The accuracy of the relationship was based on the probabilistic linkage of 99 hospital admissions records of patients, with known vital status, who underwent cardiac surgery at a single cardiology institute, with the death records of the state of Rio de Janeiro, Southeastern Brazil, in 2005. Linkage was conducted in four stages: standardizing the databases, blocking, matching, and rating peers. Blocking in fi ve steps was used, with blocking keys formed by a combination of variables such as soundex codes for the fi rst and last names, sex, and year of birth. The variables used for pairing were "full name" with the use of Levenshtein distance and "birth date". RESULTS:The second and fi fth blocking steps resulted in the largest number of formed pairs and the largest processing times for the matching. The fourth step required a lower processing cost. In the accuracy study, after fi ve blocking steps, the sensitivity of the linkage was 90.6%, and the specifi city was 100%. CONCLUSIONS:The probabilistic strategy used has high accuracy and can be used in studies of the effectiveness of high-complexity, high-cost cardiology procedures.

BackgroundThe efficacy of implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy-defibrillator (CRT-D) therapy has already been established in clinical trials but their effectiveness in several clinical settings remains undetermined. This study aimed to assess the effectiveness of ICD and CRT-D therapies within the Brazilian National Health System (SUS).MethodsAll patients who underwent ICD or CRT-D implantation within the SUS from 2001 to 2007 were included in the study. We compared estimated Kaplan-Meier survival curves using the Peto’s test. Prognostic factors were selected using Cox’s models.ResultsThere were included 3,295 patients in the ICD group and 681 patients in the CRT-D group. Cardiac causes accounted for 79% of all deaths in both groups and Chagas’ heart disease accounted for 31% of these deaths. In the CRT-D group, survival significantly decreased around the fourth year of follow-up, with a decrease from 59.5% to 38.3% in 5.5 months. Transvenous implantation technique was used in 62% of CRT-D patients. In-hospital case-fatality rates were higher in those undergoing surgical implantation (5.3%) than those undergoing transvenous implantation (1.6%) (p = 0.02).ConclusionsThe results show that short-term, medium-term and long-term effectiveness of ICD therapy appears to be similar to that evidenced in clinical trials. In the CRT-D group, in-hospital case-fatality and 30-day case-fatality were higher than those reported in other studies. Surgical epicardial implantation technique was performed in this group at a higher frequency than that reported in the literature and was associated with poorer short-term prognosis.

BackgroundHeart valve surgery outcomes are unknown in middle-income countries and thus cannot be used in health system decision making processes. This study estimated in-hospital mortality and medium and long-term survival.MethodsThis was a retrospective study of 78,806 patients who underwent heart valve surgery between 2001 and 2007 in Brazil. Two national databases were used, the Hospital Information System and the Mortality Information System. Kaplan-Meier survival analysis and log-rank tests were performed. Maximum and median follow-up was 7.7 and 2.8 years, respectively (0.002–7.707).ResultsValve replacement accounted for 69.1% of procedures performed. Mitral stenosis, the most common valve injury, represented 38.9% of the total. In 94.7% of mitral stenosis patients, aetiology was rheumatic heart disease. In-hospital mortality was 7.6% and was higher for women, for patients who had undergone concomitant coronary artery bypass grafting (CABG) and for the elderly. Overall survival was 69.9% at the end of follow-up. Survival was worst among elderly, male and concomitant CABG patients (P<0.001).ConclusionsRheumatic heart disease is still a major public health problem in Brazil. In-hospital mortality and global survival rates of patients who have undergone heart valve surgery were less satisfactory than those reported in high-income countries. The findings of this study can contribute to guiding decision making processes in middle-income countries similar to Brazil and others concerned with improving the quality of care.