الفهرس 
Acute Myocardial InfarctionOnly 14 pages are availabe for public view
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Abstract
Glycated hemoglobin (hemoglobin A1c, HbA1c, A1C, or Hb1c; sometimes also HbA1c) is a form of hemoglobin that is measured primarily to identify the average plasmaglucoseconcentration over prolonged periods of time. It is formed in a non-enzymatic glycation pathway by hemoglobin’s exposure to plasma glucose. Normal levels of glucose produce a normal amount of glycated hemoglobin. As the average amount of plasma glucose increases, the fraction of glycated hemoglobin increases in a predictable way.
This work aimed to study the prognostic significance of glycated hemoglobin during the first month after acute myocardial infarction in non-diabetic patients.
It included 62 consecutive non-diabetic patients with an acute ST segment elevation myocardial infarction. The mean age of patients admitted with acute myocardial infarction during this period was 58.38 + 9.279 ranging from 34-76 years. There were 46 male, 16 female. The BMI ranged from 26 to 31. 25 smoker patients and27 hypertensive patients.
The following investigations were done for patients:
1- Full history taking and clinical examination.
2- 12-lead surface ECGs, daily and when needed.
3- Echocardiography, to estimate LV ejection fraction and wall motion score index.
4- Laboratory investigation:
In addition to the routine laboratory tests the followings were estimated:
a) Troponin & CK-MB.
b) Fasting blood sugar &2 hours post-prandial blood sugar.
c) HbA1c, patients were divided into two groups according to the admission HbA1c: group A with HbA1c levels < 5.6 mg/dl and group B with HbA1c levels > 5.7 mg/dl to 6.4 mg/dl.
d) Elective coronary angiography to show extent of coronary lesion in eligible patients.
Group A included 25 patients (40%) and group B included37 patients (60%) denoting the common prevalence of pre-diabetic state among patients with acute MI.
The demographic and coronary risk factors data in the present study showed no significant differences between both groups and so, their confounding effects on the clinical outcomes are nearly equal in both groups and hence minimizing the bias that would be introduced when evaluating the prognostic values of elevated HbA1c.
The age range was 34-75 years with mean age 55.8 + 9.89 in group A where the age range was 45-76 years with mean age 60.13 + 8.56 in group B (p=0.07, table 1).
The male percentage was 72% in group A versus 75.67% in group B (p= 0.74, table 1). The mean BMI was 27.76 + 1.3 in group A versus 28.10 + 1.26 in group B (p= 0.29, table 1).
The prevalence of hypertension was 52% in group A versus 40.5% in group B (p=0.37, table 3, figure 3), smoking habit was 44% in group A versus 40.5% in group B (p= 78, table 3, figure 3) and hypercholesterolemia was 16% in group A versus 18.9% in group B (
p= 0.67, table 3, figure 3).
The laboratory data showed that the mean peak CK-MB was 75.56 + 16.85 in group A versus 97.56 + 24.98 in group B (p= 0.023, table 2, figure 2), the mean fasting blood sugar was 91.16 + 7.29 in group A versus 118.27 + 3.99 in group B (p=0.001, table 2, figure 2),the mean 2-hour post-prandial blood sugar was 127.68 + 9.59 in group A versus 169.40 + 4.60 in group B (p=0.001, table 2, figure 2) and the mean glycated Hb was 5.49 + 0.09 in group A versus 5.99 + 0.09 in group B ( p=0.03, table 2, figure 2).
The clinical outcomes by the end of the first month after infarction in the present study showed that patients in group B had more incidence of cardiac events and more severe coronary artery disease compared to group A.
As regard the LV function, group B patients had significantly lower EF (47.51 + 7.38 vs.51.4 + 4.60, p=0.019, table 6 figure 6) than group A. Group B had significantly higher incidence of heart failure (37.8 % vs. 16%, p=0.007 table 7 and figure 7) than group A.
As regard severity of coronary artery disease, group B had significantly higher peak of CK-MB (97.56 +24.9 vs. 75.56 + 16.85 mg/dl, p=0.023, table 2) and higher index of wall motion abnormalities (1.95 + 0.77 vs. 1.56 + 0.56, p=0.029, table 6). Additionally, 60% of those underwent coronary angiography had multivessel disease in group B while all patients in group A had either single or 2-vessele disease (table 8). Correlation studies showed highly significant correlation of HbA1c and peak CK-MB and wall motion index (table 10).
As regard recurrence of ischemia or re-infarction, group B had insignificant incidence of post-MI angina (46% vs. 48%, p=0.45) but they had significantly higher rate of re-infarction (19% vs. 4%, p=0.05, table 7) compared to group A.
Group B had insignificant higher rate of major arrhythmias (43% vs. 24%, p= 0.15, table 7) and insignificant higher mortality rate (10% vs. 4%, p=0.19, table 7) compared to group A.
The differences did not reach a significant level due to small number of the sample and short period of follow-up.
In general the total events per patient in group B was significantly higher than that in group A (1.57 vs. 0.95, p=0.01, table 7).
So, the results of the present study suggest that pre-diabetic subjects (those in group B with HbA1c between 5.6 mg/dl and 6.4 mg/dl) had more infarct size, more extensive coronary artery disease and higher incidence of post-MI complications and hence more worse short-term prognosis than group A who had normal level of HbA1c (<5.6 mg/dl).
The data between groups were tabulated and statistically analyzed.