Effect of magnesium on the monophasic action potential during early ischemia in the in vivo human heart

Journal of the American College of Cardiology
S R RedwoodT Treasure

Abstract

This study sought to examine the effects of magnesium on epicardial action potential duration in patients during early myocardial ischemia. Magnesium has been shown to reduce arrhythmias in experimental models of myocardial ischemia. Experimental and clinical observations suggest an effect on repolarization. Patients undergoing elective coronary artery bypass surgery were randomized (double blind) to receive intravenous magnesium (n = 10) or placebo (n = 10). Patients were placed on cardiopulmonary bypass and paced at 600 ms, and stable monophasic action potentials were obtained. Ischemia was achieved by aortic cross-clamping for 2 min while normothermia was maintained. Serum magnesium levels increased from 0.60 +/- 0.03 to 1.69 +/- 0.07 mmol/liter (mean +/- SEM) in the magnesium group, with no change in the placebo group. Epicardial temperature was identical in the two groups and did not alter during ischemia. At 90% repolarization, initial action potential prolongation was observed in the placebo group over the first minute of ischemia (282.0 +/- 6.0 to 294.0 +/- 4.8 ms) but not in the magnesium group (278.3 +/- 5.9 to 274.5 +/- 7.4 ms). At 2 min of ischemia, action potential duration was shorter in the magnesium group than i...Continue Reading

References

Jan 1, 1991·Annual Review of Physiology·H Matsuda
Jan 1, 1988·Circulation Research·S H Litovsky, C Antzelevitch
Dec 6, 1988·European Journal of Pharmacology·G E Billman, R S Hoskins
Apr 1, 1993·Journal of Cardiovascular Electrophysiology·S Banai, D Tzivoni

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Citations

Jan 15, 2000·International Journal of Cardiology·M Vaturi, B Strasberg
Nov 30, 2000·Anesthesiology Clinics of North America·D S Prough
May 29, 2007·Experimental and Molecular Pathology·D Radford Shanklin
May 4, 2000·Journal of Cardiothoracic and Vascular Anesthesia·A BarakaN Kawkabani
Aug 26, 1998·Lancet·J R Weisinger, E Bellorín-Font
Mar 31, 2007·Journal of the American College of Cardiology·David N KenigsbergSubramaniam C Krishnan
Nov 30, 1999·Scandinavian Cardiovascular Journal : SCJ·H J Parikka, L K Toivonen
Jul 17, 1998·Anesthesiology·M N Gomez
Jan 24, 2021·Toxicological Sciences : an Official Journal of the Society of Toxicology·Pierre JordaanNajah Abi-Gerges

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