Prophylaxis to Reduce Postoperative Atrial Fibrillation in Cardiac Surgery

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Peter C. Donovan, Maine Medical Center
ClinicalTrials.gov Identifier:
NCT00953212
First received: August 5, 2009
Last updated: May 10, 2012
Last verified: May 2012
  Purpose

Atrial Fibrillation (AF) is a common postoperative complication of cardiac surgery, occuring in approximately 25-30% of coronary artery bypass graft (CABG) patients and 35-40% of heart valve repair/replacement patients. Efforts to decrease the high rates of AF have not made great inroads to the problem. The current standard of care is the use of preoperative and postoperative beta blockers. We propose to compare the use of prophylactic oral ascorbic acid with and without prophylactic oral amiodarone, in combination with oral beta blockers, for the prevention of atrial fibrillation after open heart surgery. The hypothesis is that either drug, or a combination of the two drugs, will be superior and safe when compared to beta blockers alone.


Condition Intervention Phase
Atrial Fibrillation
Atrial Flutter
Drug: beta blockers
Drug: amiodarone
Drug: ascorbic acid
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Factorial Assignment
Masking: Double Blind (Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: A Randomized Controlled Trial to Compare Prophylaxis With Oral Ascorbic Acid, Oral Amiodarone or Both in Combination With Beta Blockers to Reduce Postoperative Atrial Fibrillation After Cardiac Surgery

Resource links provided by NLM:


Further study details as provided by Maine Medical Center:

Primary Outcome Measures:
  • Occurence of post-operative atrial fibrillation requiring treatment after open heart surgery [ Time Frame: 5 postoperative days ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Mortality [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Hospital Length of Stay [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • ICU Length of Stay [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Stroke [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Low Output Heart Failure [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Postoperative Vasoplegia [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Respiratory Failure requiring reintubation [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Bradycardia necessitating permanent pacemaker placement [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Acute Kidney Injury [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Readmission to ICU for treatment of atrial fibrillation [ Time Frame: 30 days ] [ Designated as safety issue: No ]
  • Readmission to hospital for treatment of atrial fibrillation [ Time Frame: 30 days ] [ Designated as safety issue: No ]

Enrollment: 304
Study Start Date: August 2009
Study Completion Date: February 2012
Primary Completion Date: January 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Group A
Beta Blockers, Ascorbic Acid and Amiodarone
Drug: beta blockers
metoprolol 25mg by mouth every 6 hours
Other Names:
  • Lopressor
  • Toprol XL
Drug: amiodarone
amiodarone 600mg by mouth evening before surgery amiodarone 600mg by mouth morning of surgery amiodarone 400mg by mouth every 12 hours for 3 days postoperatively
Other Name: Cordarone
Drug: ascorbic acid
ascorbic acid 2,000mg by mouth evening before surgery ascorbic acid 2,000mg by mouth morning of surgery ascorbic acid 1,000mg by mouth every 12 hours for 5 postoperative days
Other Name: vitamin C
Active Comparator: Group B
Beta Blockers and Ascorbic Acid
Drug: beta blockers
metoprolol 25mg by mouth every 6 hours
Other Names:
  • Lopressor
  • Toprol XL
Drug: ascorbic acid
ascorbic acid 2,000mg by mouth evening before surgery ascorbic acid 2,000mg by mouth morning of surgery ascorbic acid 1,000mg by mouth every 12 hours for 5 postoperative days
Other Name: vitamin C
Active Comparator: Group C
Beta Blockers and Amiodarone
Drug: beta blockers
metoprolol 25mg by mouth every 6 hours
Other Names:
  • Lopressor
  • Toprol XL
Drug: amiodarone
amiodarone 600mg by mouth evening before surgery amiodarone 600mg by mouth morning of surgery amiodarone 400mg by mouth every 12 hours for 3 days postoperatively
Other Name: Cordarone
Active Comparator: Group D
Beta Blockers alone
Drug: beta blockers
metoprolol 25mg by mouth every 6 hours
Other Names:
  • Lopressor
  • Toprol XL

Detailed Description:

Atrial fibrillation is a common complication of cardiac surgery which is associated with increased morbidity, length of stay and cost. Efforts to mitigate this problem with beta blockers and amiodarone have been met with limited success. Observational data suggests that prophylactic amiodarone has been helpful in decreasing the incidence of AF as well as increasing its ease of management. The opportunity to use ascorbic acid for AF prophylaxis is attractive because of its low side effect profile, wide acceptance and low cost.

We have designed a prospective, randomized, controlled trial using a 2 X 2 factorial design to determine whether prophylactic ascorbic acid alone, ascorbic acid with amiodarone, or amiodarone alone, when given along with beta blockers will decrease the incidence of postoperative AF in adult cardiac surgery in all comers as compared with beta blockers alone.

Patients will be randomized into four groups, A, B, C, and D. All groups will receive beta blockers, Group A will receive beta blockers, ascorbic acid, and amiodarone, Group B will receive ascorbic acid and Beta blockers, Group C will receive amiodarone and beta blockers and Group D will receive only beta blockers.

Success of randomization will be assessed by comparing treatment groups with respect to baseline characteristics, using t-tests or their nonparametric equivalent (as appropriate) for continuous variables and chisquare tests or Fisher's exact tests for categorical variables. The primary hypotheses of the effects of ascorbic acid and amiodarone on incidence of atrial fibrillation will be tested using chisquare tests for differences in proportions. No adjustment will be made for multiple comparisons since both hypotheses are pre-specified. We will use exploratory analyses including stratification to assess for the possibility of effect modification between ascorbic acid and amiodarone. If an interaction is suggested by these analyses, we will use logistic regression with a cross-product term as a formal statistical test for interaction.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • adults (18 years of age or older)
  • all comers for elective or urgent open heart surgery ( CABG, Valve repair or replacement, Combined CABG/Valves, CABG/other, Other)

Exclusion Criteria:

  • patients who refuse to participate
  • patients with a history of atrial fibrillation or atrial flutter
  • pediatric patients (under 18 years of age)
  • Emergency surgery
  • patients with contraindications to study medications
  • patients with untreated thyroid disease, hepatic failure, pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00953212

Locations
United States, Maine
Maine Medical Center
Portland, Maine, United States, 04102
Sponsors and Collaborators
Maine Medical Center
Investigators
Principal Investigator: Peter C Donovan, PA-C, MHS Maine Medical Center
Study Chair: Robert S Kramer, M.D. Maine Medical Center
  More Information

No publications provided

Responsible Party: Peter C. Donovan, Staff Physician Assistant, Cardiothoracic Surgery, Maine Medical Center
ClinicalTrials.gov Identifier: NCT00953212     History of Changes
Other Study ID Numbers: MMC-3514
Study First Received: August 5, 2009
Last Updated: May 10, 2012
Health Authority: United States: Institutional Review Board

Keywords provided by Maine Medical Center:
atrial fibrillation
cardiac surgery
open heart surgery

Additional relevant MeSH terms:
Atrial Fibrillation
Atrial Flutter
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Adrenergic beta-Antagonists
Amiodarone
Ascorbic Acid
Adrenergic Antagonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
Physiological Effects of Drugs
Anti-Arrhythmia Agents
Cardiovascular Agents
Therapeutic Uses
Enzyme Inhibitors
Vasodilator Agents
Antioxidants
Protective Agents
Vitamins
Micronutrients
Growth Substances

ClinicalTrials.gov processed this record on July 29, 2014