What Are The Tests To Check For Blocked Heart Arteries?

Posted on Mon, 3 Feb 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Mon, 3 Feb 2014 Answered on

Fri, 21 Feb 2014 Last reviewed on

Question : Hi, I have a high cholesterol reading of 7.1 with an LDL reading of around 4.5. What would be the recommended way to find out how blocked the heart arteries are, if they are blocked at all? Would a cardiac CT scan be useful or a cardiac MRI and how do the two differ? How would a cardiac calcium score differ from the cardiac CT? Thankyou.

Answered by Dr. Benard Shehu (1 hour later)

Brief Answer: Coronary CT angiography is the recommended exams.. Detailed Answer: Hi XXXXXXX I read your query very carefully. You have high cholesterol blood levels that is associated with an increase risk for Ischemic Heart Disease (IHD). The recommended way to find out if the arteries are blocked, are Stress test and Heart scan (Coronary Ct calcium scan. The recommended way to find out how blocked the heart arteries are, are Coronary CT angiography and conventional angiography. The heart scan serve as a detector of coronary atherosclerotic plaque and as predictor of the likelihood and severity of IHD. It doesn't show the exact localisation and how blocked the arteries are. The Coronary angio CT serve to evaluate the exact localisation of atherosclerotic plaque and the degree of the narrowing of coronary arteries (how blocked the heart arteries are). Hope it answere dto your query! Dr. Benard

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Benard Shehu (16 hours later)

Dear Dr. Benard, Thanks for the explanation. I can understand the better specific information provided by CT angiography. Is there any role or benefit from cardiac MRI, given that it does involve radiation? Also, is the current thinking that the level of blockage or plaque deposits is not a good indicator of the risk of cardiac events, given that hardened plaque usually does not rupture and cause blockages? Thankyou.

Answered by Dr. Benard Shehu (10 hours later)

Brief Answer: The level of blockage is a good indicator... Detailed Answer: Hi Thank you for following up. The cardiac MRI has a little role at the moment for diagnosis and the severity of IHD. The level of blockage is a good indicator of the severity of the disease especially when it’s used on the light of other relevant clinical data (severity of angina, ECG, Stress test ect). As a rule a level of blockage > 70% of the coronary arteries has a great risk for future coronary events and should be treated with coronary stent or other revascularization therapy. A level of blockage between 50 - 70% of the coronary arteries should be evaluated on the light of mentioned clinical data. If they suggest for IHD than revascularization procedure are needed. A level of blockage < 50% of the coronary arteries should be treated with healthy lifestyle change and medical therapy. No need for revascularization therapy. Hope it answered to your query! Dr. Benard

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Benard Shehu (18 hours later)

Dear Dr. Benard, Thankyou. Lastly, I am unsure how cardiac CT differs from CT angiogram. Is CT angiogram one of the procedures which come under cardiac CT? Thanks.

Answered by Dr. Benard Shehu (20 minutes later)

Brief Answer: CTangiogram use I.V contrast,premedication needed. Detailed Answer: Hi again XXXXXXX and thank you for following up. Cardiac CT is the standard procedure without any contrast agent. The CT angiography is the same procedure with the use of intra venous contrast agent. Based on your medical history data you are allergic to penicillin. So you have to consult an allergist to take a premedication scheme, before going for any procedure that use contrast agent (such as coronary angiography and CT angiography). Hope it was of help! Dr. Benard

Above answer was peer-reviewed by : Dr. Shanthi.E