Coronary Angiography
Coronary angiography is the gold standard diagnostic tool to diagnose coronary
artery disease. Besides coronary arteries, it is also used to visualize carotid
arteries, intracranial arteries, aorta and its branches, upper and lower
extremities, renal arteries, pulmonary arteries etc. With the help of contrast
injection to the targeted vessel and visualization of the vessels using x-ray, the
angiography of a vessel is performed. This procedure is used both to diagnose
and treat the problems in the arterial blood vessels.
Coronary Balloon Angioplasty:
Coronary balloon angioplasty is a procedure done to dilate the stenotic or occluded segment of a blood vessel and maintain the flow of blood. This is performed mostly on lower extremities and coronary arteries. Sometimes balloon angioplasty is enough for treatment, however in coronary arteries most of the time angioplasty is followed by coronary stenting.
What is a Coronary Stent?
Coronary Stents are made up of the combination of special inert metals like cobalt, nickel, platinum, stainless etc, silicon and fabric combination. These are placed in stenotic or totally occluded segments of the blood vessel after angioplasty(balloon dilatation) and prevent the vessels from narrowing because of recoil. After stent implantation patients should be treated with
antiaggregation therapy for a certain period of time to prevent stent thrombosis.
Frequently Asked Questions
How is the angioplasty and stenting procedure done?
By the use of a special catheter we reach the ostium of the culprit vessel. Guidewire is used to cross the occluded or stenotic segment. Balloon advanced through these guidewire is used to dilate the vessel and the stent is placed to maintain the patency for a long period of time.
How many types of Stents are there? What are Drug Eluting stents? What are Biodegradable Stents?
Stents can be classified as Bare Metal Stents, Drug Eluting Stents and Biodegradable Stents
Bare Metal Stents are stents without drugs that prevent the endothelial growth inside stents. That is why the restenosis rate in these stents are as high as %20-30 in some studies
Drug Eluting Stents are stents which elute drugs like sirolimus, everolimus which help to prevent endothelial growth and the restenosis rate is as low as
%5-10.
Stents once placed in the coronary remain there until the end of our life.
Biodegradable Stents are the stents made up of certain polymers which get resolved in our body after a certain period of time and no residue or metal is left in the vessel. So the patient can have bypass surgery in the future if needed. So these stents were used in young patients with long LAD lesions but the studies showed that the stent thrombosis was high in these stents.
However the technology is evolving and new biodegradable stents with promising results have been launched in recent years. Long term results are yet to be received.
Is Balloon Angioplasty and Coronary Stenting a procedure with high risk?
Severe complications are rare in balloon angioplasty and stent. The risk of open surgery during the procedure is reported %1-2% but has declined in recent years due to the improvement in the materials and increase in expertise of the doctors.
However special lesions like bifurcation lesions, chronic total occlusion( CTO), severely calcified lesions and patients with previous stroke are prone to higher
risk. So the complex procedure should be performed only in the center with surgical back up.
What are the advantages of Balloon Angioplasty and Stents?
In this modern era most coronary artery disease can be treated with coronary angioplasty and coronary stents. The procedure takes about an hour and patients are discharged the following day. There is not any incision and scar, no need for sedation or general anesthesia and compilation rate is very low.
However patients with multivessel disease along with diabetes, heart failure and high SYNTAX score can benefit more from bypass surgery.