Identifying factors associated with appropriate and inappropriate therapies in patients with implantable cardioverter-defibrillator (ICD) could help to identify those at risk and reduce the incidence of this emergency situation which has detrimental effect on mortality and morbidity in patients with ICD. These studies were designed to find the prevalence and factors associated with appropriate and inappropriate therapies in patients with ICD.

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-07-14T11:34:00Z No. of bitstreams: 2 Dissertação - Antonio Malan Cavalcanti Lima - 2011.pdf: 2459077 bytes, checksum: 66c327e4dee048354559d0f37ebf807e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-07-14T11:45:20Z (GMT) No. of bitstreams: 2 Dissertação - Antonio Malan Cavalcanti Lima - 2011.pdf: 2459077 bytes, checksum: 66c327e4dee048354559d0f37ebf807e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-07-14T11:45:20Z (GMT). No. of bitstreams: 2 Dissertação - Antonio Malan Cavalcanti Lima - 2011.pdf: 2459077 bytes, checksum: 66c327e4dee048354559d0f37ebf807e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2011-12-12 / Background: Chagas’s heart disease remains a major public health problem in Brazil. Sudden death is the leading cause of decease, because of that, the implantable cardioverter defibrillator (ICD) has become an important therapeutic option in this disease. Objective: To define the prevalence and predictors of electrical storm (ES) in patients with Chronic Chagas Heart Disease (CCh) with an ICD. Methods: We retrospectively studied 81 consecutive patients with CCh in whom an ICD was implanted between January 2004 to December 2007, with a mean follow up of 45,9 ± 15 months. Patients were classified into two groups according to the presence of ES episodes. We compared baseline and funcional characteristics. p values less than 0,05 were considered statistically significant. Results: Thirty five patients (43,2%) developed TE during follow up. By univariate analysis, QRS width ≥ 150 ms (p=0,001), previous pacemaker (p=0,001), ventricular tachycardia (VT) for indication of ICD (p=0,001) and cumulative percent ventricular pacing (C%VP) > 40%/80%) were all predictors of TE. However, by multivariate analysis only the indication of ICD for VT (odds ratio (OR) = 9.16, 95% CI: 1.98 to 42.78, p = 0.005) and C%VP > 40%/80% (OR = 6.30, 95% CI: 1.56 to 25.49, p = 0.010) were independent predictors of TE. Conclusion: 1- ES is very frequent in subjects with CCh and ICD; 2- Indication of ICD for VT and C%VP > 40%/80% were independent predictors of TE. / Fundamento: A Cardiopatia Chagásica ainda é um importante problema de saúde pública no Brasil. A morte súbita é a principal causa de óbito, por isto, o cardioversor desfibrilador implantável (CDI) tornou-se importante opção terapêutica nesta doença. Objetivos: Avaliar a prevalência e fatores preditores da tempestade arritmogênica ou elétrica (TA ou TE) em pacientes chagásicos portadores de CDI. Metodologia: Estudo retrospectivo de uma coorte de 81 pacientes chagásicos submetidos a implante de CDI entre Janeiro de 2004 a Dezembro de 2007, com seguimento médio de 45,9 ± 15 meses.Os pacientes foram classificados em dois grupos de acordo com a presença ou não de TE. Comparou-se as características basais e funcionais da amostra utilizando-se testes estastísticos (t student, qui-quadrado e, quando necessário, Fisher). Resultados: A idade foi de 57,0 ± 9,5 anos, sexo masculino 60 (74,1%), a fração de ejeção (FE) média foi de 43,8 ± 7,6. Dos 81 casos da amostra, 35 (43,2%) apresentaram pelo menos um episódio de TE. Estes tiveram um total de 378 TE com média de 10,8 ± 11,6. Em análise univariada, identificou-se que a indicação do CDI por taquicardia ventricular sustentada espontanea (TVSE) (p=0,001), duração do QRS (dQRS) ≥ 150ms (p= 0,001), ser portador de marcapasso (MP) (p=0,001) , percentagem de estímulo de ventrículo direito (PEVD) > 40%/80% (p= 0,001) e classe funcional (CF) final III/IV (p= 0,015), foram fatores preditores de TE nesta coorte. Porém, a análise multivariada demonstrou que apenas a indicação de CDI por TVSE ( odds ratio (OR)= 9,16; IC 95%: 1,98- 42,78; p= 0,005) e PEVD > 40%/80% ( OR=6,30; IC 95%: 1,56-25,49; p=0,010 ) foram fatores preditores independentes para TE. Conclusão: Nos pacientes chagásicos portadores de CDI, houve elevada prevalência de TE (43,3%). Os fatores preditores independentes para TE foram: TVS (TVSE) prévia e PEVD > 40%/80%.

Identifying factors associated with appropriate and inappropriate therapies in patients with implantable cardioverter-defibrillator (ICD) could help to identify those at risk and reduce the incidence of this emergency situation which has detrimental effect on mortality and morbidity in patients with ICD. These studies were designed to find the prevalence and factors associated with appropriate and inappropriate therapies in patients with ICD.