What diagnostic technique is considered the 'gold standard' for diagnosing coronary heart disease (CHD)?

Coronary Angiography is recognized as the gold standard for diagnosing coronary heart disease (CHD) primarily because it provides direct visualization of the coronary arteries. This invasive procedure involves the injection of contrast dye into the coronary arteries, followed by the use of X-ray imaging to observe blood flow and identify any blockages or narrowing. This level of detail allows for accurate assessment of the severity and location of any coronary artery disease, which is critical for determining appropriate treatment.

Other diagnostic techniques, while useful, do not offer the same level of specificity or detail regarding the coronary arteries. An electrocardiogram primarily evaluates the electrical activity of the heart and can indicate if there are issues but does not directly visualize the arteries. CT angiography is a non-invasive imaging test that can show coronary artery blockages but may not be as definitive as coronary angiography in certain cases. A chest X-ray looks at the general structure of the heart and lungs and is not specifically designed to diagnose CHD.

Thus, Coronary Angiography stands out as the definitive method for diagnosing coronary heart disease, providing crucial information that guides further medical management and intervention.