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Revista Brasileira de Cirurgia Cardiovascular
On-line version ISSN 1678-9741
LEAL, João Carlos F. et al. Impact of serum troponin I in the long-term evolution of patients submitted to resynchronization with biventricular stimulation: follow-up of up to 59 months. Rev Bras Cir Cardiovasc [online]. 2005, vol.20, n.3, pp. 286-290. ISSN 1678-9741. http://dx.doi.org/10.1590/S0102-76382005000300009.
OBJECTIVE: To analyze the evolution and prognostic influence of the cardiac troponin I serum levels in patients with congestive heart failure (CHF) submitted to interventricular resynchronization (VR) over a 59-month follow-up period. METHOD: Thirty-three patients with idiopathic dilated myocardiopathy in NYHA functional classes III and IV were submitted to VR. The pre- and post-operative quality of life (QV) was analyzed using the Minnesota Code and the left ventricle function was assessed by echocardiography. The cardiac troponin I levels were compared in 23 patients utilizing the Fisher exact test to analyze the correlation with death and the Kaplan-Meier curve was used to analyze the survival rate. RESULTS: The QV was better after VR with a median of 73 points in the pre-operative period and 36 in the postoperative period (p-value < 0.0001). The left ventricle diastolic diameter (LVDD) reduced from 65 mm in the preoperative period to 60 mm in the postoperative period (p-value = 0.0014) with an increase in the ejection fraction from 37 to 47% (p-value = 0.0004). In 15 patients with normal cardiac troponin I levels, no deaths occurred and of the 8 patients with high levels, six died (p-value = 0.0003). The actuarial survival curve showed a survival rate of 47.1 ± 13.3% at the end of 59 months. CONCLUSION: VR in patients with CHF improves the QV and echocardiographic parameters (ejection fraction and LVDD). It is a good alternative for functional class III and IV patients. The serum levels of cardiac troponin I are predictors of risk to life.
Keywords : Troponin; Arrhythmia; Heart failure [congestive]; Pacemaker [artificial].