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Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
Published on: February 26, 2013
The combination of propranolol and magnesium does not prevent postoperative atrial fibrillation
A J Solomon1, A K Berger, K K Trivedi
1Department of Medicine, Georgetown University Medical Center, Washington, DC 20007, USA. solomona@gunet.georgetown.edu
Insights
Adjunctive magnesium sulfate did not reduce the incidence of postoperative atrial fibrillation when combined with propranolol in coronary artery bypass patients. This combination therapy did not improve upon beta-blocker efficacy for preventing this common complication.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Atrial fibrillation is a frequent complication following cardiovascular surgery.
- Beta-blockers are effective in reducing postoperative atrial fibrillation.
- The role of magnesium in preventing this complication remains debated.
Purpose of the Study:
- To investigate if magnesium sulfate, when added to propranolol, enhances the prevention of postoperative atrial fibrillation.
- To evaluate the efficacy of combination therapy versus beta-blocker monotherapy.
Main Methods:
- A prospective randomized trial involving 167 coronary artery bypass patients.
- Patients received either propranolol alone or propranolol plus magnesium sulfate.
- Magnesium administration began intraoperatively, with propranolol initiated in the intensive care unit.
Main Results:
- Intention-to-treat analysis showed no significant difference in postoperative atrial fibrillation rates between groups (19.5% vs. 22.4%, p = 0.65).
- Combination therapy led to increased postoperative hypotension, necessitating propranolol dose adjustments.
- On-treatment analysis also revealed no statistically significant difference in atrial fibrillation incidence (18.5% vs. 10.0%, p = 0.20).
Conclusions:
- Adjunctive magnesium sulfate does not improve the efficacy of propranolol in preventing postoperative atrial fibrillation.
- The combination therapy did not demonstrate a significant benefit over propranolol alone.
- Further research may be needed to explore alternative strategies for atrial fibrillation prevention.
Background:
Atrial fibrillation is a common complication of cardiovascular surgery. Beta-blockers have been shown to decrease the incidence of postoperative atrial fibrillation. However, the use of magnesium is more controversial. It was our hypothesis that adjunctive magnesium sulfate would improve the efficacy of beta-blockers alone in the prevention of postoperative atrial fibrillation.
Methods:
We prospectively randomized 167 coronary artery bypass patients (mean age 61+/-10 years, 115 men) to receive propranolol alone (20 mg four times daily) or propranolol and magnesium (18 g over 24 hours). Magnesium was begun intraoperatively, and propranolol was started on admission to the intensive care unit.
Results:
Using an intention-to-treat analysis, the incidence of postoperative atrial fibrillation was 19.5% in the propranolol-treated patients and 22.4% in propranolol + magnesium-treated patients (p = 0.65). Because combination therapy resulted in an excess of postoperative hypotension, which required withholding doses of propranolol, an on-treatment analysis was also performed. In this analysis, the incidence of atrial fibrillation was still not significantly different (18.5% in propranolol-treated patients and 10.0% in propranolol + magnesium-treated patients, p = 0.20).
Conclusions:
Adjunctive magnesium sulfate, in combination with propranolol, does not decrease the incidence of postoperative atrial fibrillation.
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