title: Mechanical alternans is associated with mortality in acute hospitalized heart failure: prospective mechanical alternans study (MAS).
abstract: BACKGROUND
  Acute hospitalized heart failure (AHHF) is associated with 40% to 50% risk of death or rehospitalization within 6 months after discharge. Timely (before hospital discharge) risk stratification of patients with AHHF is crucial. We hypothesized that mechanical alternans (MA) and T-wave alternans (TWA) are associated with postdischarge outcomes in patients with AHHF.
  
  
  RESULTS
  A prospective cohort study was conducted in the intensive cardiac care unit and enrolled 133 patients (59.6±15.7 years; 65% men) admitted with AHHF. Surface ECG and peripheral arterial blood pressure waveform via arterial line were recorded continuously during the intensive cardiac care unit stay. MA and TWA were measured by enhanced modified moving average method. All-cause death or heart transplant served as a combined primary end point. MA was observed in 28 patients (25%), whereas TWA was detected in 33 patients (33%). If present, MA was tightly coupled with TWA. Mean TWA amplitude was larger in patients with both TWA and MA when compared with patients with lone TWA (median, 37 [interquartile range, 26-61] versus 22 [21-23] μV; P=0.045). After a median of 10-month postdischarge, 42 (38%) patients died and 2 had heart transplants. MA was associated with the primary end point in univariable Cox model (hazard ratio, 1.84; 95% confidence interval, 1.00-3.40; P=0.05) and after adjustment for left ventricular ejection fraction, New York Heart Association HF class, and implanted implantable cardioverter defibrillator/cardiac resynchronization therapy defibrillator (hazard ratio, 2.12 95% confidence interval, 1.13-3.98; P=0.020). TWA without consideration of simultaneous MA was not significantly associated with primary end point (hazard ratio, 1.42; 95% confidence interval, 0.77-2.64; P=0.260).
  
  
  CONCLUSIONS
  MA is independently associated with outcomes in AHHF.
  
  
  BACKGROUND
  URL: http://www.clinicaltrials.gov. Unique identifier: NCT01557465.
authors.affiliation: Whiting School of Engineering, The Johns Hopkins University, Baltimore, MD.
authors.forename: Robert
authors.initials: R
authors.lastname: Kim
authors.forename: Oscar
authors.initials: O
authors.lastname: Cingolani
authors.forename: Ilan
authors.initials: I
authors.lastname: Wittstein
authors.forename: Rhondalyn
authors.initials: R
authors.lastname: McLean
authors.forename: Lichy
authors.initials: L
authors.lastname: Han
authors.forename: Kailun
authors.initials: K
authors.lastname: Cheng
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Robinson
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Brinker
authors.forename: Steven S
authors.initials: SS
authors.lastname: Schulman
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Berger
authors.forename: Charles A
authors.initials: CA
authors.lastname: Henrikson
authors.forename: Larisa G
authors.initials: LG
authors.lastname: Tereshchenko
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007297:Inpatients; D008297:Male; D008396:Maryland / Q000453:epidemiology; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D016896:Treatment Outcome; D016277:Ventricular Function, Left
keywords: alternans; heart failure; mortality