CT Coronary Angiography

What is a CTA of the Coronary Arteries?

CT Angiography is a noninvasive imaging study that helps see fat and calcium deposits that have accumulated in the coronary arteries. These deposits, called plaques, can lead to blockages which can cause chest pain, shortness of breath, and/or heart attacks. If you have high cholesterol levels, high blood pressure, a family history of heart disease, diabetes, and/or smoke, you may be at risk for developing these plaques.

Who should consider CTA of the Coronary Arteries?

Patients should discuss with their primary physician or cardiologist whether this study would be helpful to assess their cardiac health. The most common reasons to order a CTA of the Coronary Arteries are to:

• Assess individuals with atypical symptoms for coronary artery disease (such as chest pain or shortness of breath unrelated to physical exertion).
• Evaluate symptomatic high-risk patients with normal stress tests who are not candidates for cardiac catheterization.
• Further evaluate cardiac health after inconclusive stress test results or stress test results that don’t match the patient’s symptoms.
• Evaluate cardiac bypass grafts and/or stents for blockages.

Why It Is Done?

A CT angiogram is done to look for:

• A narrowing (stenosis) or blockage in the coronary arteries. This can occur when there is a buildup of fat (cholesterol) and calcium in the arteries. This buildup is called plaque.
• Heart problems, such as pericarditis (a buildup of fluid around the heart) and damage or injury to the heart valves.
• A bulge (aneurysm) or tear (dissection) in the aorta camera.gif, which is a large blood vessel that carries blood from the heart to the rest of the body.
• A blood clot in the lungs (pulmonary embolism).
• A narrowing of the veins in the leg (peripheral arterial disease).
• An abnormal pattern of blood vessels that may be a sign of a tumor.

How is this study performed?

Pictures are taken of the heart and coronary arteries using a special type of x-ray machine called a 128-slice multi-detector CT scanner. These pictures are obtained while contrast dye is given intravenously. The patient lies on an open table within a large donut-like structure that takes the pictures. The CTA scan is pain-free and takes 10 minutes.

How do I prepare for a CTA of the Coronary Arteries?

• 4-5 hours fasting – NPO (water can be taken).
• Do not stop the medicines for Heart and Blood Pressure, if any.
• Heart rate and BP of the patient will be checked before undergoing CT Angio. Heart rate lowering medication will be given if required.
• Diabetic patients can continue taking medicine as in routine except medicines having “Metformin”. (In case he is taking “Metformin”, it should be stopped 36 to 48 hours before CTA).
• History of Allergy/Asthma is required.
• Patient must bring the prescription of the referring Cardiologist & old record.
• Avoid caffeine and smoking 12 hours prior to the procedure to avoid cardiac stimulations.
• Creatinine will be checked before CT.

NOTE :- Metformin is the generic name of a medicine its market name may be different, patient may confirm from his/her physician.

Guidelines for requesting Physician

• Indications.
• Serum Creatinine checks.
• History of allergy/asthma.
• Heart rate lowering medications.
• Explanation of procedure and procedure risk including contrast reaction.
• NPO for minimum of 04 hours.
• Advise for stopping Metformin 24 to 48 hrs. before CT Coronary test.

Guidelines for Radiology Department

• Consent for procedure
• Explanation of procedure in a friendly manner
• Check pulse, blood pressure and serum creatinine
• History of allergy /asthma (No Beta Blocker to be used).
• ECG check, if required and will be as FOC.
• Breathing exercise to check breath holding in MO Room.
• IV line (18 G canola right ante-cubital fossa vein) in MO Room.
• Beta Blocker/other heart rate lowering medications (Not in Asthmatic patients).

    Beta Blocker contraindications:

• Systolic Blood pressure less than 105 mmHg.
• Active wheeze or history of Asthma.
• CHF (Congestive Heart Failure), Swollen feet & breathless on lying flat.
• If pulse is 65-75 beats per minutes, give Lopressor 50mg orally and scan after 45 minutes, if pulse is <60 beats per minute. If patient cannot wait, give IV Lopressor 05 mg and check heart rate and scan if <60 beats per minute.
• If heart rate > 75 beats per minute give 100 mg Lopressor orally and wait for 45 minutes or give 30 mg as 10 mg increments. Scan at any time, if heart rate is < 60 beats per minute. If heart rate > 75 beats per minute, after maximum dose of Lopressor, then cancel procedure. Check blood pressure before each dose of Lopressor.
• If contraindication to Beta-Blocker, give Diltiazem 60 mg orally or 90 mg orally depending on blood pressure, if patient cannot wait.
• IV Diltiazem or Verapamil (discuss with cardiologist).
• Ivabradine (Ivatab or other trade name) 7.5 mg stat oral can be given to asthmatics. Scan at any time if heart rate < 60 beats per minutes. If heart rate > 70 beats per minute, discuss with cardiologist.
• 8-10 drops of Rivotril, after the consultation of Cardiologist.