BACKGROUND: Cardiospecific proteins of the troponin-tropomyosin complex in the contractile system of the cardiomyocytes have challenged creatine kinase isoenzyme MB (CK-MB) as the "gold standard" for the early biochemical detection of acute myocardial injury.OBJECTIVE: To investigate cardiac troponin Ⅰ messager RNA (cTnI-mRNA) in peripheral blood and its clinical values in diagnosis of patients with myocardial injury.DESIGN: A basic and observational study for set up a method to analyze cTnI-mRNA.SETTING: Department of Cardiology, Affiliated Hospital, Nantong University.MATERIALS: The project was accomplished from May 2003 to May 2005 in Research Center of Clinical Molecular Biology, and Department of Pathology, Affiliated Hospital, Nantong University. The cTnI-mRNA was detected from blood by a nested PCR assay, and its clinical values as a sensitive myocardial diagnostic marker were confirmed in patients with myocardial injury.METHODS: Pathologic features and microstructure of cardiac myocytes were examined by H&E staining or electron microscopy. The cTnI-mRNA was extracted from blood and synthesized to cDNA through random primers and reverse transcriptase, and amplified by a nested PCR assay, and its clinical values as a myocardial diagnostic marker were investigated in patients with myocardial injury.MAIN OUTCOME MEASURES: Microstructure of cardiomyocytes, sensitivity of analysis method and diagnostic values.RESULTS: Microstructure of cardiomyocytes with mitochondria swell,rupture, vacancy-like denaturation, nucleus abnormality, and chromatin condensed were observed by electron microscopy. The cTnI-mRNA fragments from heart and blood were successfully amplified and the sensitivity was 2 pg/μL. The product sequences from tissues or blood were confirmed by sequencing. The cTnI-mRNA from cardiac myocytes was found that it present in blood plasma and not in circulating nucleus cell. The incidence of blood cTnI-mRNA of chronic cardiomyopathy was significantly higher (P ＜ 0.05) than that of serum enzymatic patterns or cTnI quality,respectively.CONCLUSION: The analysis of blood cTnI-mRNA is a sensitive marker for diagnosis and monitoring of myocardial injury.

The receptor of the heart transplantation was a patient with terminal dilated cardiomyopathy, the donor was a patient with congenital ventricular septal defect, in situ double-chamber heart transplantation was performed, and the result of the four-year follow-up was satisfactory. At present, donor is deficient,and those donors with congenital defect can also obtain satisfactory clinical application effects after appropriate handling.