title: Left bundle branch block as an electrocardiographic pattern at presentation of patients with Tako-tsubo cardiomyopathy.
abstract: BACKGROUND
  Tako-tsubo cardiomyopathy (TTC) is a recently described clinical condition that may mimic acute myocardial infarction. The presence or new onset of left bundle branch block (LBBB) is associated with adverse outcome in patients with acute myocardial infarction.
  
  
  OBJECTIVE
  We sought to assess the incidence, clinical profile, and outcome of patients with TTC and LBBB at presentation.
  
  
  RESULTS
  From July 2003 to December 2006, 84 consecutive patients met the diagnostic criteria for TTC. LBBB was present in eight (9%) patients at presentation. Patients with LBBB tended to be older (77 +/- 11 years versus 72 +/- 10 years; P=0.186), and with a more frequent, but not statistically significant, history of hypertension (75 versus 53%; P=0.227), and chronic renal failure (25 versus 8%, P=0.117). Moreover, patients with LBBB showed a higher peak creatine kinase-MB value (76 +/- 32 U/I versus 21 +/- 31 U/I; P=0.005), and a lower, but not significantly, baseline left ventricular ejection fraction (30 +/- 13% versus 36 +/- 9%; P=0.107), as compared with patients without LBBB. Follow-up length was 12 +/- 10 months. The mortality rate was higher in patients with LBBB as compared with those without (25 and 3%; P=0.005). However, at Cox analysis the only independent predictor of death was age (P=0.042).
  
  
  CONCLUSIONS
  LBBB was documented at presentation in 9% of TTC patients. At long-term follow-up, TTC patients with LBBB showed increased unadjusted mortality. However, when adjusted for age, baseline characteristics, and concomitant diseases, LBBB did not appear to be an independent predictor of poor outcome in patients with TTC.
authors.affiliation: Department of Cardiology, Careggi Hospital, University of Florence, Florence, Italy. parodiguido@libero.it
authors.forename: Guido
authors.initials: G
authors.lastname: Parodi
authors.forename: Claudia
authors.initials: C
authors.lastname: Salvadori
authors.forename: Stefano
authors.initials: S
authors.lastname: Del Pace
authors.forename: Benedetta
authors.initials: B
authors.lastname: Bellandi
authors.forename: Nazario
authors.initials: N
authors.lastname: Carrabba
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Gensini
authors.forename: David
authors.initials: D
authors.lastname: Antoniucci
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000209:etiology; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality; D003937:Diagnosis, Differential; D004562:Electrocardiography; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D054549:Takotsubo Cardiomyopathy / Q000150:complications / Q000175:diagnosis* / Q000401:mortality; D013997:Time Factors