title: Clinical implications of midventricular obstruction and intravenous propranolol use in transient left ventricular apical ballooning (Tako-tsubo cardiomyopathy).
abstract: BACKGROUND
  Persistent hypotension with dynamic midventricular obstruction (MVO) in patients with transient left ventricular (LV) apical ballooning (Tako-tsubo cardiomyopathy) is an important complication that needs to be treated.
  
  
  OBJECTIVE
  The objective of this study is to determine the effects of intravenous propranolol challenge on MVO in transient LV apical ballooning.
  
  
  METHODS
  Thirty-four patients (12 males, 22 females, mean age 64 +/- 17 years, age range 22-84 years) with LV apical ballooning were enrolled. The hemodynamic and echocardiographic effects of propranolol (0.05 mg/kg, maximum 4 mg) were analyzed in 13 patients.
  
  
  RESULTS
  (1) Midventricular obstruction was present in 8 (24%) of 34 patients, and the pressure gradient (PG) ranged from 28 to 140 mm Hg. (2) Patients with MVO had similar demographic and clinical characteristics (symptoms, peak creatine kinase, plasma catecholamine levels) as those without MVO; however, in patients with MVO, abnormal Q waves on electrocardiogram and hypotension were more prevalent. (3) In the MVO group, intravenous propranolol changed the PG from 90 +/- 42 to 22 +/- 9 mm Hg, the systolic blood pressure (SBP) from 85 +/- 11 to 116 +/- 20 mm Hg, and the LV ejection fraction (LVEF) from 30% +/- 7% to 43% +/- 4%. (4) In all subjects, the changes in the PG after propranolol injection had a significant linear correlation with the SBP and LVEF changes: deltaSBP = 4.738 + 0.315 x deltaPG (r = 0.689 (P < .001) and deltaLVEF = 2.973 + 0.1321 x deltaPG (r = 0.715, P < .001).
  
  
  CONCLUSIONS
  Intravenous propranolol is useful for treating dynamic MVO in patients with transient LV apical ballooning.
authors.affiliation: Second Department of Internal Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Yoshioka
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Hashimoto
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Tsuchihashi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nagao
authors.forename: Michifumi
authors.initials: M
authors.lastname: Kyuma
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ooiwa
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nozawa
authors.forename: Shinya
authors.initials: S
authors.lastname: Shimoshige
authors.forename: Mariko
authors.initials: M
authors.lastname: Eguchi
authors.forename: Takeru
authors.initials: T
authors.lastname: Wakabayashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yuda
authors.forename: Mamoru
authors.initials: M
authors.lastname: Hase
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Nakata
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Shimamoto
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D004305:Dose-Response Relationship, Drug; D004452:Echocardiography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D011433:Propranolol / Q000008:administration & dosage*; D013318:Stroke Volume / Q000502:physiology; D054549:Takotsubo Cardiomyopathy / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D014694:Ventricular Outflow Obstruction / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology
chemical_list: D000319:Adrenergic beta-Antagonists; D011433:Propranolol