Eichhorn E J, Tandon P K, DiBianco R, Timmis G C, Fenster P E, Shannon J, Packer M
Cardiac Catheterization Laboratory, University of Texas Southwestern Medical Center, Dallas 75216.
J Am Coll Cardiol. 1993 Mar 1;21(3):634-40. doi: 10.1016/0735-1097(93)90095-i.
The aim of this study was to determine the prognostic significance of alterations in serum magnesium in patients with moderate to severe congestive heart failure.
Reductions in serum magnesium have been postulated to play a role in promoting arrhythmias and to have an adverse impact on survival in congestive heart failure, although support for this postulate is lacking.
Serum magnesium levels were measured in 1,068 patients enrolled in a survival study of class III or IV heart failure at the time of double-blind randomization to milrinone, a phosphodiesterase inhibitor, or placebo. All patients received conventional therapy with digoxin, diuretic drugs and a converting enzyme inhibitor throughout the trial. The median follow-up period was 6.1 months (range 1 day to 20 months).
Patients with high serum magnesium (defined as > or = 1.9 mEq/liter, n = 242) were less likely to survive than were patients with a normal magnesium level (n = 627) (p < 0.05, risk ratio = 1.41). Patients with a low magnesium level (defined as < or = 1.5 mEq/liter, n = 199) had no difference in survival compared with the group with a normal magnesium level (p = NS, risk ratio = 0.89). At baseline, the patients in the high magnesium group were older and had more severe functional and renal impairment. An analysis after adjustment for these variables demonstrated no difference in survival comparing the low, normal and high magnesium groups. Although the three groups had no difference in frequency of ventricular tachycardia, length of longest run or frequency of ventricular premature beats on baseline Holter monitoring, the group with hypomagnesemia had more frequent ventricular couplets.
Serum magnesium does not appear to be an independent risk factor for either sudden death or death due to all causes in patients with moderate to severe heart failure. Hypomagnesemia is associated with an increase in the frequency of certain forms of ventricular ectopic activity, but this is not associated with an increase in clinical events. The higher mortality rate among the patients with hypermagnesemia is attributable to older age, more advanced heart failure and renal insufficiency.
本研究旨在确定血清镁变化在中重度充血性心力衰竭患者中的预后意义。
尽管缺乏对这一假设的支持，但有人推测血清镁降低在促进心律失常方面起作用，并对充血性心力衰竭患者的生存产生不利影响。
在一项针对III或IV级心力衰竭患者的生存研究中，对1068例患者在双盲随机分组接受米力农（一种磷酸二酯酶抑制剂）或安慰剂时测定血清镁水平。在整个试验过程中，所有患者均接受地高辛、利尿剂和转换酶抑制剂的常规治疗。中位随访期为6.1个月（范围1天至20个月）。
血清镁水平高（定义为≥1.9 mEq/升，n = 242）的患者比镁水平正常（n = 627）的患者存活可能性小（p < 0.05，风险比 = 1.41）。镁水平低（定义为≤1.5 mEq/升，n = 199）的患者与镁水平正常组相比，生存率无差异（p = 无显著性差异，风险比 = 0.89）。在基线时，高镁组患者年龄更大，功能和肾功能损害更严重。对这些变量进行调整后的分析表明，低、正常和高镁组在生存率方面无差异。尽管三组在基线动态心电图监测时室性心动过速频率、最长发作时间或室性早搏频率方面无差异，但低镁血症组室性成对搏动更频繁。
血清镁似乎不是中重度心力衰竭患者猝死或全因死亡的独立危险因素。低镁血症与某些形式的室性异位活动频率增加有关，但这与临床事件增加无关。高镁血症患者较高的死亡率归因于年龄较大、心力衰竭更严重和肾功能不全。
