The register study CGM@CAD will examine whether cardiogoniometry can provide additional information concerning the indication for a diagnostic coronary angiography and if so, which additional value it has. Therefore, an additional cardiogoniometry will be carried out in consecutive patients who have been diagnosed with myocardial ischemia by means of established methods (exercise ECG, stress echocardiography, myocardial scintigraphy, or stress-MRT) and for whom an intracardiac catheter examination is regarded as indicated. The results of the different methods - particularly the results of the exercise ECG and the cardiogoniometry - will be checked against the results of the invasive examination as gold standard and the discharge diagnosis with regards to any correlation.