Kuopio,
Finland-
The incidence of AF has been reported to be 20-40% after
coronary bypass graft (CABG) surgery, and is even higher after
valve and combined valve and bypass surgery. A potential
mechanism for the AF is an exaggerated inflammatory response,
demonstrated by increased levels of complement, C-reactive
protein complex, and number of white blood cells in patients who
develop AF. Jari Halonen, MD et al from Kuopio University
Hospital in Kuopio, Finland investigated whether intravenous
corticosteroids administered after cardiac surgery prevents AF
after cardiac surgery. Their results, published in the April 11,
2007 issue of the Journal of the American Medical Association
concluded that intravenous hydrocortisone reduced the
incidence of AF after cardiac surgery.
This experiment was a double-blind,
randomized multicenter trial in 3 university hospitals in
Finland that
involved 241 patients. These patients had no prior history of AF
and were undergoing their first CABG surgery, aortic valve
replacement, or combined CABG surgery and aortic valve
replacement. Patients were randomized to receive either 100mg
hydrocortisone or matching placebo. The first dose was given on
the evening of the operative day followed by one dose every 8
hours for the next 3 days. All patients also received metoprolol
(50-150mg/d) titrated to heart rate. AF episodes lasting longer
than 5 minutes that occurred within 84 hours after cardiac
surgery were recognized as the primary end point.
Of the
patients receiving placebo after their cardiac surgery, 48% of
them had AF, while only 30% of those patients receiving
hydrocortisone experienced AF after their surgery (Hazard ratio
[HR], 0.54; 95% CI, 0.36-0.82; P=.01; number needed to treat,
5.6). The relative risk reduction was 37%. Additionally, the
first episode of AF occurred later in patients randomized to the
hydrocortisone group (P=.003). The concentrations of C-reactive
protein on the first, second, and third post-operative days were
significantly lower in the hydrocortisone group than in the
placebo group. Administration of hydrocortisone therapy was
well-tolerated with no serious complications arising from
administration of the drug. Corticosteroids have been shown to
also reduce post-operative nausea, vomiting, and anorexia and
may improve the absorption of oral medications, such as
β-blockers.
Intravenous
administration of hydrocortisone is efficacious and
well-tolerated in the prevention of AF after cardiac surgery. A
meta-analysis including 2 other trials was consistent with the
conclusion that corticosteroid therapy is associated with lower
incidence of postoperative AF (risk ratio, 0.67; 95% CI,
0.54-0.84; P=.001).
Co-authors:
Jari Halonen, MD; Pirjo Halonen, PhD; Otso Järvinen, MD, PhD;
Panu Taskinen, MD; Tommi Auvinen, MD; Matti Tarkka, MD, PhD;
Mikko Hippeläinen, MD, PhD; Tatu Juvonen, MD, PhD; Juha
Hartikainen, MD, PhD; Tapio Hakala, MD, PhD.