Biochemical markers of cardiac diseases

Synopsis of Biomarkers of Atheromatous Plaque Formation, Rupture and Thrombosis in the Diagnosis of Acute Coronary Syndromes

Acute coronary syndrome is the main cause of mortality and morbidity worldwide and early diagnosis is a challenge for clinicians. Though cardiac Troponin, the most commonly used biomarker, is the gold standard for myocardial necrosis, it is blind for ischemia without necrosis. Therefore, ideal biomarkers are essential in the care of patients presenting with symptoms suggestive of cardiac ischemia. The ideal biomarker or group of biomarkers of atheromatous plaque formation, rupture and thrombosis for timely and accurate diagnosis of acute coronary syndrome is a current need. Therefore, we discuss the existing understanding and future of biomarkers of atheromatous plaque formation, rupture and thrombosis of acute coronary syndrome in this review. Keywords were searched from Medline, ISI, IBSS and Google Scholar databases. Further, the authors conducted a manual search of other relevant journals and reference lists of primary articles. The development of high-sensitivity troponin assays facilitates earlier exclusion of acute coronary syndrome, contributing to a reduced length of stay at the emergency department, and earlier treatment resulting in better outcomes. Although researchers have investigated biomarkers of atheromatous plaque formation, rupture and thrombosis to help early diagnosis of cardiac ischemia, most of them necessitate validation from further analysis. Among these biomarkers, pregnancy-associated plasma protein-A, intercellular adhesion molecule-1, and endothelial cell-specific molecule- 1(endocan) have shown promising results in the early diagnosis of acute coronary syndrome but need further evaluation. However, the use of a combination of biomarkers representing varying pathophysiological mechanisms of cardiac ischemia will support risk assessment, diagnosis and prognosis in these patients and this is the way forward.

Cardiovascular Mortality in Hemodialysis Patients: Clinical and Epidemiological Analysis

Cardiovascular diseases are the leading cause of death in hemodialysis (HD) patients. The annual cardiovascular mortality rate in these patients is 9%, with left ventricular (LV) hypertrophy, ischemic heart disease and heart failure being the most prevalent causes of death. The aim of this study was to determine the cardiovascular mortality rate and estimate the influence of risk factors on cardiovascular mortality in HD patients. A total of 115 patients undergoing HD for at least 6 months were investigated. Initially a cross-sectional study was performed, followed by a two-year follow-up study. Beside the standard biochemical parameters, C-reactive protein (CRP), homocysteine, cardiac troponins (cTn) and the echocardiographic parameters of LV morphology and function (LV mass index, LV fractional shortening, LV ejection fraction) were determined. Results were analyzed using Cox regression analysis, Kaplan-Meier and Log-Rank tests. The average one-year cardiovascular mortality rate was 8.51%. Multivariate Cox regression analysis identified increased CRP, cTn T and I, and LV mass index as independent risk factors for cardiovascular mortality. Patients with cTnT > 0.10 ng/mL and CRP > 10 mg/L had significantly higher cardiovascular mortality risk (p < 0.01) than patients with cTnT > 0.10 ng/mL and CRP ≤ 10 mg/L and those with cTnT ≤ 0.10 ng/mL and CRP ≤ 10 mg/L (p < 0.01). HD patients with high cTnT and CRP have a higher cardiovascular mortality risk.

Cardiac involvement of major thalassemia and evaluation of total serum creatine kinase and creatine kinase-mB isoenzyme and cardiac troponinI in these patients

The goal of this study was the evaluation of specific markers of myocardial injury that includes CK-MB and troponin I in major thalassemic patients. Regular blood transfusion is the main treatment in major thalassemia. One of the most important complications of regular blood transfusion is iron overload that eventually involves many organs like heart and cause myocardial injury. Sixty patients with transfusion-dependent major thalassemia, at the age range of 8 to 15 years in Tabriz Pediatric Medical Center were chosen. Measurement of Hb, Hct and serum ferritin were performed in hospital laboratory, but total serum Creatine Kinase (CK) by photometric and isoenzyme of CK-MB by immunologic DGKC and cardiac troponin I (cTnI) were tested by ELISA methods in Shaheed Madani heart center laboratory before blood transfusion. For all patients echocardiography and ECG assessment of cardiac function were done by a pediatric cardiologist and results were statistically analyzed. Forty nine patients (group A) had normal left ventricular ejection fraction (LVEF = 50-70%) and 11 patients (group B) had reduced LVEF (20-45%). There was no statistical difference between two groups in average volume of blood transfusion (p = 0.074). Although total CK and CK-MB isoenzyme were higher in group B but there was no statistically meaningful difference between two groups (p = 0.123, p = 0.111). Troponin I also was higher in group B but statistically analysis showed no correlation between cardiac function and troponin I level in these groups (p = 0.827). This study showed that cardiac markers are not helpful for recognition of cardiac involvement in major thalassemia.

Biochemical Markers of Atherosclerosis

This paper is a brief review of some lipid parameters and serum markers of inflammation in a view of their predictive relevance for the atherosclerotic disease. A discourse on the importance of measuring different lipids and lipoproteins, concentration of LDL particles and apolipoprotein levels is still underway. Also, the recommendations for apolipoprotein (a), phenotypization and other lipid markers have not yet been established. In recent years the recommendations imply simultaneous measuring of multiple markers and calculating the lipid index values such as lipid tetrad index (LTI), lipid pentad index (LPI) and atherogenic index of plasma (AIP). Several circulating markers of inflammation such as C-reactive protein, serum fibrinogen and elevated leukocyte number, are consistently associated with atherosclerosis. In spite of a lack of evidence on measuring the C-reactive protein in a wide population, the guidelines for its application in diagnostics and therapy of coronary heart disease were developed. Some proinflammatory cytokines, adhesion molecules and markers of leukocyte activation are promising markers, requiring, however, more detailed prospective evaluation. The question to be elucidated is if these inflammatory markers are directly involved in the pathogenic process.