title: Benefits of cardiac resynchronization therapy in "very dilated cardiomyopathy".
abstract: BACKGROUND
  Recent clinical trials have studied parameters that could predict response to cardiac resynchronization therapy (CRT) in patients with advanced heart failure. Left ventricular end-diastolic dimension (LVEDD) is regarded as a possible predictor of response to CRT.
  
  
  OBJECTIVE
  To study the response to CRT in patients with very dilated cardiomyopathy, i.e. those at a more advanced stage of the pathology, analyzing both the responder rate and reverse remodeling in two groups of patients classified according to LVEDD.
  
  
  METHODS
  We performed a retrospective analysis of 71 patients who underwent CRT (aged 62 +/- 11 years; 65% male; 93% in NYHA functional class > or = III; 31% with ischemic cardiomyopathy; left ventricular ejection fraction [LVEF] 25.6 +/- 6.8%; 32% in atrial fibrillation; QRS 176 +/- 31 ms). Twenty-two (31%) patients with LVEDD > or = 45 mm/m2 (49.2 +/- 3.5 mm/m2) were considered to have very dilated cardiomyopathy (Group A) and 49 patients had LVEDD > 37 mm/m2 and < 45 mm/m2 (39.4 +/- 3.8 mm/m2) (Group B). All patients were assessed by two-dimensional echocardiography at baseline and six months after CRT. The following parameters were analyzed: NYHA functional class, LVEF and LVEDD. Responders were defined clinically (improvement of > or = 1 NYHA class) and by echocardiography, with a minimum 15% increase over baseline LVEF combined with a reduction in LVEDD (reverse remodeling).
  
  
  RESULTS
  There were no significant differences in baseline demographic characteristics between the two groups. At six-month followup, we observed an improvement in LVEF (delta 8.5 +/- 11.8%) and a reduction in LVEDD (delta 3.7 +/- 6.8 mm/m2), with fifty-seven (79%) patients being classified as clinical responders. The percentage of patients with reverse remodeling was similar in both groups (64% vs. 73%, p = NS), as were percentages of improved LVEF (delta 6.3 +/- 11% vs. delta 9.6 +/- 12%; p = NS) and decreased LVEDD (delta 3.7 +/- 5.5 mm/m2 vs. delta 3.7 +/- 7.4 mm/m2; p = NS). We found a higher percentage of clinical responders in patients with very dilated cardiomyopathy (96% vs. 72%, p < 0.05).
  
  
  CONCLUSIONS
  In this study, a significant number of responders showed reverse remodeling after CRT. Although a higher percentage of patients with very dilated cardiomyopathy showed improvement in functional class, the extent of reverse remodeling was similar in both groups.
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Lisboa, Portugal. lousinha@hotmail.com
authors.forename: Ana
authors.initials: A
authors.lastname: Lousinha
authors.forename: Mário M
authors.initials: MM
authors.lastname: Oliveira
authors.forename: Joana
authors.initials: J
authors.lastname: Feliciano
authors.forename: Ana
authors.initials: A
authors.lastname: Galrinho
authors.forename: Luísa Moura
authors.initials: LM
authors.lastname: Branco
authors.forename: Pedro Silva
authors.initials: PS
authors.lastname: Cunha
authors.forename: Hamad
authors.initials: H
authors.lastname: Hamad
authors.forename: Ruben
authors.initials: R
authors.lastname: Ramos
authors.forename: João
authors.initials: J
authors.lastname: Abreu
authors.forename: Ana
authors.initials: A
authors.lastname: Leal
authors.forename: Sofia
authors.initials: S
authors.lastname: Santos
authors.forename: Rui
authors.initials: R
authors.lastname: Soares
authors.forename: Manuel Nogueira
authors.initials: MN
authors.lastname: da Silva
authors.forename: Rui Cruz
authors.initials: RC
authors.lastname: Ferreira
mesh_terms: D058406:Cardiac Resynchronization Therapy; D002311:Cardiomyopathy, Dilated / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index