Lower risk of postoperative arrhythmias in congenital heart surgery following intraoperative administration of magnesium

Abstract

As many as one third of our patients undergoing congenital heart surgery had postoperative arrhythmias. Use of intraoperative magnesium was associated with a reduction in the odds of occurrence of all postoperative arrhythmias. Our results do not provide evidence that a greater dose of magnesium is associated with greater arrhythmia risk reduction. Despite the intraoperative use of magnesium, there continued to be a high residual incidence of postoperative arrhythmias, raising the question for studying new or additional agents.

Magnesium, Oxidative Stress, Inflammation, and Cardiovascular Disease

“…Mg has been used to treat different types of arrhythmias for decades, such as AF [ 43 , 44 , 45 , 198 , 199 ], TdP [ 41 , 42 , 200 ], and VA [ 46 , 47 , 199 ] (for reviews [ 6 , 201 , 202 , 203 , 204 ]). Mg is also frequently used in patients undergoing cardiac and pulmonary surgery when lethal arrhythmias often occur [ 44 , 199 , 204 , 205 , 206 ]. For example, a meta-analysis of randomized controlled trials on 2069 patients demonstrates that prophylactic Mg administration (IV MgSO 4 or MgCl 2 ) reduces the risk of supraventricular tachycardia and VA after cardiac surgery [ 205 ].…”

“…Higher incidence of postoperative AF is observed in patients with lower plasma Mg levels [ 208 ]. IV Mg prevents AF after cardiac and thoracic surgery [ 199 , 204 , 205 , 209 ] and non-cardiac thoracic surgery [ 198 ]. IV Mg also helps control the ventricular rate in patients with AF as an adjunct to digoxin [ 203 ].…”

Epsom salts and the unorthodox journey of a mineral from a natural saline spring

“…This group has previously published on the salutary effects of intraoperative magnesium in the prevention of junctional ectopic tachycardia. 4 With the same cohort of patients, the current study of He and colleagues 3 expands into other types of arrhythmias, including heart block. This is controversial, because heart block develops most often after surgical trauma and is unlikely to be affected by intraoperative magnesium administration.…”

“…Among these, blocking calcium influx into myocardial cells, inhibiting acetylcholine release from motor nerve terminals, and inhibiting histamine release from mast cells have particular beneficial effects in preventing arrhythmias after cardiac surgery. 2 In this issue of the Journal, He and colleagues 3 have published their retrospective observational study analyzing the effects of intraoperative magnesium sulfate administration in the prevention of postoperative arrhythmias in children undergoing heart surgery in a 9-year period. This singleinstitution experience represents the largest cohort and case mix study to date.…”

“…Although intuitively there is a higher likelihood of occurrence of any arrhythmia with higher complexity and adjusted risk for each surgical procedure, this was not the case in the study of He and colleagues. 3 Perhaps this was related to their use of an outdated risk assessment tool, such as the ARISTOTLE score, which lumps procedures differently than the current STAT score, potentially confounding the generalization of the results.…”