title: Transient QRS amplitude attenuation is associated with clinical recovery in patients with takotsubo cardiomyopathy.
abstract: OBJECTIVE
  Low voltage QRS complexes (LQRSV) and amplitude attenuation of QRS voltage (AAQRS) have been described in takotsubo (TC) patients, and postulated as valuable pre-angiographic markers. The aim of this observational study is to evaluate potential diagnostic and prognostic features of QRS amplitude in TC and acute coronary syndrome (ACS) patients.
  
  
  METHODS
  Fifty-eight patients with TC were matched with 58 patients with ACS according to age, gender, and presence or absence of ST elevation at hospital admission. A 12-lead ECG was recorded within 12h after symptoms onset, the day after coronary angiography (CA) and before hospital discharge. When available, ECGs prior and subsequent to the acute event were also collected.
  
  
  RESULTS
  QRS amplitude showed a time related trend, with a first phase characterized by an initial decrease in amplitude in both groups and a second phase, with a progressive recovery of QRS amplitude in TC patients up to pre-event levels, while QRS amplitude in ACS patients remained substantially unchanged from admission onwards. Rise in AAQRS during hospitalization showed a positive linear association with systolic function recovery and both troponin I and CK-MB decrease (all p<0.01) in TC patients. A 20% increase of mean AAQRS from admission is able to predict LVEF recovery and troponin I and CK-MB normalization in TC patients with good sensitivity and specificity.
  
  
  CONCLUSIONS
  LQRSV and AAQRS are not reliable in differentiating ACS from TC. However, QRS amplitude attenuation in TC is transient, and is linearly associated with systolic function recovery and cardiac biomarkers normalization.
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy. Electronic address: f.guerra@univpm.it.
authors.forename: Federico
authors.initials: F
authors.lastname: Guerra
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Giannini
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Pongetti
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy.
authors.forename: Azzurra
authors.initials: A
authors.lastname: Fabbrizioli
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy.
authors.forename: Edlira
authors.initials: E
authors.lastname: Rrapaj
authors.affiliation: Department of Cardiology, "Guglielmo Da Saliceto" Hospital, Piacenza, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Aschieri
authors.affiliation: Department of Cardiology, "Guglielmo Da Saliceto" Hospital, Piacenza, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Pelizzoni
authors.affiliation: Department of Cardiology, "Guglielmo Da Saliceto" Hospital, Piacenza, Italy.
authors.forename: Giovanni Q
authors.initials: GQ
authors.lastname: Villani
authors.affiliation: Icahn School of Medicine at Mount Sinai, New York/Cardiology Division, Elmhurst Hospital Center, Elmhurst, NY, USA.
authors.forename: John E
authors.initials: JE
authors.lastname: Madias
authors.affiliation: Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Ospedali Riuniti", Ancona, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Capucci
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D017023:Coronary Angiography; D052279:Creatine Kinase, MB Form / Q000097:blood; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020127:Recovery of Function; D012189:Retrospective Studies; D054549:Takotsubo Cardiomyopathy / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D019210:Troponin I / Q000097:blood; D020107:Troponin T / Q000097:blood
chemical_list: D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T; D052279:Creatine Kinase, MB Form
keywords: Acute coronary syndrome; ECG; QRS amplitude; QRS voltage; Takotsubo cardiomyopathy