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The Diagnosis of Chronic Coronary Heart Disease.

BACKGROUND
Chronic coronary heart disease (CHD) and acute myocardial infarction are endemic conditions. In Germany, an estimated 900 000 cardiac catheterizations were performed in the year 2014, and a percutaneous intervention was carried out in 40% of these procedures. It would be desirable to lessen the number of invasive diagnostic procedures while preserving the reliability of diagnosis. In this article, we present the updated recommendations of the German National Care Guideline for Chronic CHD with regard to diagnostic evaluation.


METHODS
Updated recommendations for the diagnostic evaluation of chronic CHD were developed on the basis of existing guidelines and a systematic literature review and approved by a formal consensus process.


RESULTS
8-11% of patients with chest pain who present to a general practitioner and 20-25% of those who present to a cardiologist have chronic CHD. General practitioners should estimate the probability of CHD with the Marburg Heart Score. Specialists can use detailed tables for determining the pre-test probability of CHD; if this lies in the range of 15% to 85%, then non-invasive tests should be primarily used for evaluation and treatment planning. If the pretest probability is less than 15%, other potential causes should be ruled out first. If it is over 85%, the presence of CHD should be presumed and treatment planning should be initiated. Coronary angiography is needed only if therapeutic implications are expected (revascularization). Psychosocial risk factors for the development and course of CHD and the patient's quality of life should be regularly assessed as well.


CONCLUSION
Non-invasive testing and invasive coronary angiography should be used only if their findings are expected to have therapeutic implications. Psychosocial risk factors, the quality of life, and adherence to treatment are important components of these patients' diagnostic evaluation and long-term care.