Patient Q: Male 66 years old Recently, Lei feels chest tightness, palpitations and an increase in premature ventricular contractions during activities such as walking or going upstairs. He has no chronic diseases such as hypertension, hyperlipidemia or diabetes mellitus. During one episode, the ECG showed an increase in premature ventricular contractions, but no ischemic changes were observed. Is this a case of coronary heart disease? How to further investigate? Doctor’s answer: Although this case does not have classical coronary heart disease risk factors such as hypertension, hyperlipidemia and diabetes, its clinical symptoms have the characteristics of coronary angina, i.e. chest tightness related to physical activity. Angina can be manifested as chest pain, chest tightness, squeezing sensation and a myriad of other symptoms, but the unchanging feature is related to exertion, and this alone is more than 90% certainty of diagnosis. As for the increase of premature beats after activity in this case, it cannot be used as a basis for the diagnosis of coronary heart disease. There are more than 200 risk factors for coronary heart disease, in addition to the classical ones, for example, increased waist circumference is listed as one of the independent risk factors. The further diagnostic steps I think can be done by first doing a plate exercise test, if it is negative and there is no angina symptoms, then basically excluding coronary heart disease; if the plate exercise test result is suspicious or positive then further isotope myocardial perfusion (ECT) examination should be done. In this case, even if the platelet exercise test was negative, ECT was proposed to be done again because of clear exertional chest tightness, and coronary angiography or stenting or coronary artery bypass surgery would be done if the test results showed a large ischemic area. Once the diagnosis of coronary artery disease is established, medical treatment is also important. Why not use coronary CT first? Currently, the international community attaches great importance to the issue of radiation, because in this case, the possibility of further isotope myocardial perfusion and coronary angiography has to be considered, and its iterative radiation exposure is too high. On the other hand, the positive predictive value of coronary CT is low, it is disturbed by heart rate, rhythm, respiration, calcification and other factors, and produces artifacts, but its negative predictive value is high. Conversely, if the prediction of coronary artery disease is unlikely in this case, then coronary CT may be given priority.