Comparison Between the New Highly Sensitive Troponin T and the Conventional Troponin T Test in Elderly Patients

All consecutive patients with acute symptoms and an age over 70 years will be recruited for the study during 6 months. Medical history, physical examination, vital signs including heart rate, blood pressure, body temperature, and any concomitant diseases are raised on admission in the Emergency Department. Blood samples are taken for determination of routine laboratory. Highly sensitive troponin T is determined as part of the routine. Troponin T is measured from the same blood sample with a conventional test of the 4th generation. A second blood sample is taken as part of routine 4-6 hours after the onset of symptoms to confirm or rule out any acute coronary syndrome. Patients are divided according to the interval between the onset of symptoms and presentation at the hospital in an "early"(<4 hours) and "late"(> = 4 hours) group.

The Barthel Index as a geriatric assessment is raised. An electrocardiogram is written in all patients at recording and evaluated. An echocardiographic examination is performed in all patients for measurement of heart valve function, left ventricular diameter, ejection fraction (LVEF) and diastolic function to differentiate into other mechanisms for the release of troponin. According to the results of the echocardiographic examination, patients are divided into sub-groups (LV-EF> = 55%) and without preserved ejection fraction (LVEF <55%). The recording physician estimates after receiving the results of the investigations and routine laboratory whether a myocardial infarction or heart failure is present. He subsequently makes the decision about further treatment. The medical records will be evaluated after completion of the stay in hospital by two experienced cardiologists, whether a heart attack, heart failure or other disease was present. High sensitivity Troponin T and Troponin T of the 4th generation are compared for the early and correct diagnosis of acute coronary syndrome.

Objectives:

• Incidence of acute coronary syndromes without ST-segment elevation in elderly patients by using the highly sensitive biomarker troponin T,
• Comparison with the incidence of acute coronary syndromes without ST-segment elevation in the same group by the use of troponin T of the 4th generation
• Survey on differential diagnoses such as heart failure or other cardiac diseases.

Inclusion criteria

• Age 70 or older
• Signed informed consent

Exclusion criteria

• Hospitalization for unstable angina pectoris within the last 2 month
• ST-segment elevation myocardial infarction
• Heart valve defects with need for surgical intervention
• Coronary bypass surgery or percutaneous transluminal angioplasty within the last 3 months
• Planned elective coronary revascularization
• Serum creatinine> 2.0 mg / dl (177 µmol / liter)
• Serum potassium> 5.5 mmol / l Limited survival probability within the next 3 months