The purpose of the investigation is to verify the efficiency of the HyperQ™ system in detecting exercise induced ischemia, with higher specificity and sensitivity than conventional ECG Stress testing. The study will be carried out by applying the HyperQ™ system during cycle ergometer stress testing in patients who are referred for angiography at the Department of Cardiology, Essen University Hospital, Essen, Germany. The HyperQ™ results will then be compared to the standard ECG stress test results using the angiography results as the gold standard. The study will be considered successful if analysis of the HyperQ provides a statistically significant improvement over the diagnostic accuracy of conventional ECG stress testing analysis.

Inclusion Criteria:

• A patient who was referred to angiography.
• A patient who is able (i.e., no contraindications) to perform an exercise stress test
• A patient who signed an informed consent form.

Exclusion Criteria:

• Contraindications for an exercise test.
• Wolff-Parkinson-White (pre-excitation) syndrome.
• Left Bundle branch block, Complete Right bundle branch block or QRS duration > 120 ms, change in QRS morphology during exercise.
• Atrial Fibrillation or significant ventricular arrhythmia
• Treatment with Digoxin.
• Pacemaker.
• Having taken beta blockers within 24 hours before the exercise test.
• Pregnancy or suspected pregnancy.

Patients referred to the West German Heart Center in Essen for coronary angiography