Serum miRNA-1 as a novel biomarker for acute myocardial infarction and unstable angina

Background: Coronary artery diseases are the predominant cause of morbidity and mortality in developed and developing countries. Thus, extraordinary efforts have been directed to determine the molecular and pathological characteristics of the diseased heart in order to develop novel diagnostic and therapeutic strategies miRNAs are class of abundant, non-coding RNAs that attracted scientists' attention for their promising role as diagnostic and prognostic biomarkers in cardiovascular diseases

Aim of the work: To identify whether miRNA-1 is a dependable biomarker for diagnosis of acute myocardial infarction or not

Subjects and Methods: 69 patients with coronary artery disease were included in this study; 36 patients with AMI and 33 patients with unstable angina. Those patients were admitted to coronary care unit, Assuit University Hospital during the period of March to October 2014. In addition 22 apparently healthy subjects were included as a control group. Cardiac troponin I and miRNA-1 was done for all subjects

Results: In patients with AMI the results of miRNA-1 ranged from 28.3 - 6763.9 fold changes above the control level. In those with UA, miRNA-1 result ranged from 1.74 - 144.37 fold changes above the control level [when the control group is one fold]. Comparison between different cups regarding results of miRNA-1 revealed that there was a highly significant difference [P<0.001] between different groups. There was a highly significant increase in patients with AMI when compared with the control group, also a statistically significant increase [P<0.001] in patients with UA when compared with the control group and a statistically significant increase [P<0.001] in patients with AMI when compared with those of UA

Conclusion: miRNA-1 is a novel dependable biomarker in patients with acute coronary syndrome. It shows significant upregulation in patients with AMI, but this upregulation is far from that of UA

Corrected QT dispersion [QTDC] improves the diagnostic performance of treadmill exercise test in diagnosing coronary artery disease [CAD]

To find out the best combination of parameters; clinical and exercise induced hemodynamic and electrocardiographs, that could improve the diagnostic performance of exercise test. Exercise test and coronary angiography were performed for 112 patients with angina pectoris and normal electrocardiogram. The univariate predictors of the presence of CAD were aged >/= 40 years, male gender, hypertension, smoking, typicality of chest pain, development exertional chest pain, shorter exercise duration, decrease systolic blood pressure [BP] >/= 10 mmHg or systolic BP 3 min post-exercise >90% peak, heart rate drop <12 b/m one minute post exercise, exercise induced ST-segment depression >/= 1 mm, ST/HR slope >/= 2.4 microV/beat/minute, increased T amplitude >/= 2.5 mm, lengthening or no change of P wave duration, decrease or no change in Q wave depth, either R wave increase >/= 2mm or decrease >/= 1mm, QTD >60 ms, QTDc >70 ms, Q-X/QT ratio in V5 >0.5 and delta QTD rest to peak exercise >/= 16 mm and. Using multivariate logistic regression analysis we proved that using either ST depression >/= 1 mm or QTDc >70 ms as a positive exercise test significantly improved the sensitivity and the negative predictive value of the test without a significant decrease in the specificity. Using either ST depression >/= 1 mm or QTDc >70 ms as a positive exercise test improves the diagnostic performance of the test