Cardiac Resynchronization Therapy

The Structural Response Is not Always Necessary


  • Raphael Chiarini
  • Carlos Eduardo Duarte
  • Thiago Rego da S Silva
  • André Brambilla Sbaraini
  • Guilherme Gaeski Passuello
  • Luciene Dias de Jesus Jesus
  • José Tarcisio Medeiros de Vasconcelos
  • Silas dos Santos Galvão Filho


Cardiac resynchronization therapy, Cardiac insuffi ciency, Echocardiography, Cardiac electrophysiology


Up to 30-40% of patients undergoing cardiac resynchronization therapy (CRT) are described as nonresponders since the initial studies. This paradigm has inspired several modifications of the devices, electrodes and surgical technique in the implant. The definition of CRT response should be rethought, standardized, and ratings based on structural and/or clinical response should be proposed. The authors discuss a series of cases in which sustained clinical improvement was achieved despite structural worsening. Objective: To assess the profi le of clinical responders to CRT who have worsened structurally. Method: It is a retrospective cohort of patients in outpatient follow-up from January 2012 to March 2017. We included 13 patients (2.7%) out of a total of 476 submitted to CRT. Inclusion criteria were to present an improvement in functional class according to the New York Heart Association criteria (FC-NYHA) ≥ 1 sustained for at least one year and absence of improvement or worsening of the structural parameters evaluated by transthoracic echocardiogram [ejection fraction (EF), diastolic diameter (LVDD) and systolic diameter (LVSD)]. The variables analyzed were age, gender, FC-NYHA, cardiopathy, echocardiographic and electrocardiographic parameters, medications in use, location of implanted electrodes, device programming, cardiary defibrillator therapies, and mortality. Statistical analysis was performed using non-parametric Wilcoxon and McNemar tests. Results: There were 13 patients, 92% male, mean age 60.9 ± 9.2 years and mean follow-up of 3.3 ± 1.1 years, 76% of CRT associated with implantable cardioverter defibrillator (CRT-D). In pre-implantation, 84.6% were in FC-NYHA III and then 61.5% were in FC-NYHA I (p = 0.001). The mean pre-implantation EF was 31.3 ± 7.6% and 26.6 ± 7.3 (p = 0.002) in the last evaluation. The predominant heart disease was non-ischemic in 92.5%, most of which were chagasic cardiomyopathy (CCM) (66%). In the TRC-D group, no shock therapy was recorded in the period; there was one death in a patient with ischemic cardiomyopathy (IC) for the septic shock of pulmonary focus after 2.2 years of follow-up. The mean QRS was 189.9 ± 23.1 ms to 157.9 ± 35.2 after CRT  (p = 0.032). There was no signifi cant change in pre-and postimplant medications during follow-up. Conclusion: The absence of structural improvement should not be considered therapeutic failure, since CRT seeks to modify the electrical activation, and may be related to better performance and decrease of symptoms, even in evolutionary heart diseases. 


Download data is not yet available.


Fuganti CJ, Melo CS, Moraes Jr AV, Pachon-Mateos JC, Pereira WL, Galvão Filho SS, et al. Diretriz: – Terapia de ressincronização cardíaca. Relampa. 2015;28(Suppl 2):S26-S40.

Chung ES, Leon AR, Tavazzi L, Sun JP, Nihoyannopoulos P, Merlino J, et al. Results of the predictors of response to CRT (PROSPECT) trial. Circulation. 2008;117(20):2608-16.

Rocha EA, Moreira FT, Quidute AR, Abreu JS, Lima WO, Rodrigues CR, et al. Quem são os super-respondedores à terapia de ressincronização cardíaca? Int J Cardiovasc Sci. 2017;30(1):61-9.

Tracy CM, Epstein AE, Darbar D, Dimarco JP, Dunbar SB, Estes NA 3rd, et al. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2012;60(14):1297-313.

Yu CM, Bleeker GB, Fung JW, Schalij MJ, Zhang Q, van der Wall EE, et al. Left ventricular reverse remodeling but not clinical improvement predicts long-term survival after cardiac

resynchronization therapy. Circulation. 2005;112(11):1580-6.

Rao RK, Kumar UN, Schafer J, Viloria E, De Lurgio D, Foster E. Reduced ventricular volumes and improved systolic function with cardiac resynchronization therapy: a randomized trial comparing simultaneous biventricular pacing, sequential biventricular pacing, and left ventricular pacing. Circulation. 2007;115(16):2136-44.

Leclercq C, Gras D, Le Helloco A, Nicol L, Daubert C. Hemodynamic importance of preserving the normal sequence of ventricular activation in permanent cardiac pacing. Am

Heart J 1995;129:1133-41.

Tracy CM, Epstein AE, Darbar D, DiMarco JP, Dunbar SB, Estes NAM. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities. A report of the American College of Cardiology Foundation/American

Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Circulation. 2012;126:1784-1800.

Comitê Coordenador da Diretriz de Insuficiência Cardíaca. Diretriz brasileira de insuficiência cardíaca crônica e aguda. Arq Bras Cardiol. 2018;111(3):436-539.

The Task Force on cardiac pacing and resynchronization therapy of the European Society of Cardiology (ESC). ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. Eur Heart J. 2013;34:2281-2329.

The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2016;37:2129-2200.

Martinelli Filho M, Peixoto GL, Siqueira SF, Martins SAM, Nishioka SAD, Costa R, et al. Terapia de ressincronização cardíaca na cardiomiopatia chagásica crônica: boa resposta clínica e pior prognóstico. Relampa. 2013;26(1):33-8.

Garillo R, Salgado Melo C, Pachón Mateos CTC, Silva Jr. O, Leite GMS, Carvalho EIJ. Pacientes não responsivos à terapia de ressincronização cardíaca. Relampa. 2007;20(3):167-74.

Menezes Junior AS, Stival WN, Lopes ISP. Indicações da terapia de ressincronização cardíaca: discussão baseada em estudos recentes. Relampa. 2014;27(1):34-9.

Linde C, Leclercq C, Rex S, Garrigue S, Lavergne T, Cazeau S, et al. Long-term benefits of BiV pacing in heart failure. JACC. 2002;40(1):111-8.


Linde C, Ellenbogen K, McAlister FA. CRT: clinical trials, guidelines, and target populations. Heart Rhythm. 2012;9(Suppl 8):S3-S13.

Rocha EA. Analysis of cardiac dyssynchrony. Arq Bras Cardiol. 2018;111(4):616-7.

Leyva F, Nisam S, Auricchio A. 20 years of cardiac resynchronization therapy. JACC. 2014;64(10):1047-58.

Papelbaum B. Galvão Filho SS, Vasconcelos JTM, Duarte CE, Chiarini R Numata BK, et al. Punção do óstio do seio coronariano ocluído para implante de eletrodo ventricular

esquerdo: uma nova alternativa. Rev Soc Cardiol Estado de São Paulo. 2018;28(4):489-91.

Nascimento EA, Wiefels Reis CC, Ribeiro FB, Alves CR, Silva EN, Ribeiro ML, et al. Relação entre dissincronismo elétrico e mecânico em pacientes Submetidos a TRC com implante do

eletrodo de VE orientado pela cintilografia GATED SPECT. Arq Bras Cardiol. 2018;111(4):607-15.

Birnie et al. Incidence of AF with adaptive CR. Heart Rhythm. 2017;14(12).

Linde C, Abraham WT, Gold MR, Daubert JC, Tang ASL, Young JB, et al. Predictors of CRT clinical response. Eur J Heart Failure. 2017:19(8):1056-63.

Melo CS, Silva Júnior LM, Vazquez BP, Oliveira JC, Salerno HD, Lage JS. Evidências atuais para indicação da terapia de ressincronização cardíaca. Relampa. 2013;26(3):151-61.

Rocha EA, Pereira FTM, Quidute ARP, Abreu JS, Lima JWO, Sobrinho CRMR, et al. Quem são os super-respondedores à ressincronização. Int J Cardiovasc Sci. 2017;30(1):61-9.

Hsu JC, Solomon SD, Bourgoun M, McNitt S, Goldenberg I, Klein H, et al; MADIT-CRT Executive Committee. Predictors of super-response to cardiac resynchronization therapy and associated improvement in clinical outcome: the MADIT-CRT (multicenter automatic defibrillator implantation trial with cardiac resynchronization therapy) study. J Am Coll Cardiol. 2012;59(25):2366-73.



How to Cite

Chiarini, R. ., Duarte, C. E. ., Silva, T. R. da S., Sbaraini, A. B. ., Passuello, G. G. ., Jesus, L. D. de J., Vasconcelos, J. T. M. de ., & Galvão Filho, S. dos S. . (2019). Cardiac Resynchronization Therapy: The Structural Response Is not Always Necessary. JOURNAL OF CARDIAC ARRHYTHMIAS, 32(1), 38–42. Retrieved from



Cardiac Pacing