Serial analysis of troponin I levels in patients with ischemic and nonischemic dilated cardiomyopathy

Abstract

SummaryBackground: Ongoing myocardial cell damage forms the basis for progression of chronic heart failure. Evidence is accumulating that progressive loss of cardiac myocytes is associated with the release of cardiac troponin I (cTnI).Hypothesis: This study sought to determine whether levels of cTnI are of prognostic value for risk stratification of patients with chronic heart failure.Methods: Release of cTnI was measured by conventional enzyme immunoassay following serum ultrafiltration in 58 consecutive patients hospitalized for chronic heart failure and 31 healthy volunteers serving as control group. Determination of serum levels was performed every 2 weeks over a time interval of 3 months. According to the results of coronary angiography, patients were divided into Group D showing normal coronary arteries (n = 33, ejection fraction 27 ± 6.1%) and Group I showing severe coronary heart disease (n = 25, ejection fraction 28.8 ± 7.8%). Survival of patients was evaluated after a mean time interval of 3 years.Results: The mean cTnI serum level over all measurements was 0.66 ± 1.8 ng/ml in patients versus 0.11 ± 0.48 ng/ml in volunteers. At all six points of analysis, the mean cTnI serum level was significantly different (p < 0.001) between patients and volunteers. There was no significant difference between patients with and without coronary heart disease following hospital discharge, however, troponin release was significantly different between survivors and nonsurvivors (n = 27) (0.56 ng/ml vs. 0.84 ng/ml; p < 0.05).

Effects of Radiation Therapy on Myocardial Cell Integrity and Pump Function: Which Role for Cardiac Biomarkers?

“…Yet while myocardial ischemia is an important factor, it is not the only reason for developing heart failure. Systolic dysfunction can occur despite normal coronary morphology, and progressive myocyte loss seems to be the key mechanism for progressive heart failure [12] . Following the trigger event, a variety of compensatory neurohumoral processes are activated which result in a normal cardiac output even in the presence of elevated filling pressures, thus keeping the patient asymptomatic.…”

“…The role of troponin I (TnI) in the detection of myocardial cell damage is already accepted worldwide, and its value for patients with acute coronary syndromes is well established. Furthermore, changes in cardiac pump function can also be accurately investigated by measuring the plasma levels of brain natriuretic peptide (BNP) [10][11][12] . Taken together, this suggests that impairment of left ventricular (LV) function induced by radiation therapy may be indicated by an increase of either TnI or BNP.…”

The Year in Heart Failure

“…Several ongoing investigations will hopefully shed more light on the potential benefits and challenges of this targeted approach (33,34). In contrast to the natriuretic peptides, sequential troponin levels have not been shown to help guide therapy despite the fact that small increases in plasma troponin levels have prognostic importance in patients with advanced heart failure (35). This may change with the emergence of a commercially available ultrasensitive troponin assay.…”

Measurement of Troponin in Cardiomyopathies

“…25 There are several studies describing chronic troponin elevation in cardiomyopathies implying ongoing sub-clinical myocyte necrosis, apoptosis or leakage. [26][27][28] In this section, we summarise the clinical studies that have examined the role of serum troponin measurement in each of the cardiomyopathies. We performed a comprehensive literature search by using electronic bibliographic databases (MEDLINE, EMBASE and The Cochrane Library) and combinations of the following keywords: troponin, biomarker, hypertrophic, obstructive, dilated, restrictive, Fabry, non-compaction, amyloid, peri-partum, arrhythmogenic and cardiomyopathy.…”

“…Patients with ischaemic cardiomyopathy have greater levels of TnI than DCM patients at hospital presentation but levels are more likely to remain elevated at 3 months in DCM. 27,62 Clinical correlates: the relationship between Tn and imaging parameters in DCM is less consistent than in HCM. Elevated Tn is associated with increased LV diameters and volumes but not always with ejection fraction.…”