Definition & Overview
Percutaneous transluminal balloon angioplasty, or angioplasty in general, is a procedure that opens a blocked blood vessel (such as an artery) using a flexible, narrow tube called a catheter. The catheter has a balloon at the tip that is inflated inside the blood vessel to widen the diameter of the blocked artery or vein.
Transluminal balloon angioplasty removes the blockage to restore normal blood flow, which can help prevent serious medical conditions including stroke or heart attack.
The blockage of visceral arteries is typically caused by fatty deposits. Visceral arteries are those that supply blood to the liver, intestine, and spleen. The fatty deposits can break off from their current location and can be carried or transported through the bloodstream. When this happens, it is possible for them to get stuck in blood vessels and cause partial or total blockage of the area. This moving particle in the blood is referred to in medicine as an embolus.
The lumen, the central cavity of a hollow structure such as a blood vessel, is very limited in that any tiny blockage can cause a haemostatic (blood flow) imbalance. This creates a domino effect in the entire human body and can affect the function of other tissues and organs because all these structures depend on the blood for oxygen and nutrient supply.
The procedure is called transluminal because the device is inserted or passed through the lumen of a certain blood vessel.
Who Should Undergo and Expected Results?
Patients diagnosed with a blocked renal or aortic artery are candidates for this procedure. The rate of success of balloon angioplasty has been consistently improving due to the increase in understanding of the condition as well as the introduction of newer techniques in treating the condition.
However, restenosis can occur especially in patients with other medical conditions or diseases such as diabetes. Recently, the issue of restenosis is becoming less common because of the use of stents.
Stents are stainless tubes with slots. They are introduced to the artery using a balloon catheter. They provide support to the inner walls of the arteries so they stay open and do not recoil or spring back to their usual diameter size.
The use of stents has remarkable effects in the treatment of stenosis or blocked vessels. It has reduced the incidence of restenosis by as much as 50%.
How is the Procedure Performed?
The team tasked to carry out percutaneous transluminal balloon angioplasty is multidisciplinary. A radiologist, cardiologist, and anaesthesiologist are involved in the procedure.
A local anaesthesia is applied to the femoral artery where a needle is inserted. A guidewire is inserted into the needle and replaced with a two-port instrument where flexible devices, such as a catheter, are inserted.
Another thinner guidewire is used to replace the initial guidewire before a catheter is passed through until it reaches the aorta or the renal artery. A dye is injected and the area is x-rayed so that doctors can see exactly the treatment area. As soon as this is done, another thinner wire that contains the balloon will replace the other one. A balloon catheter is then guided to the area where the balloon is inflated to increase the size or diameter of the target artery. The balloon is inflated and deflated several times until the desirable size is achieved.
A stent is then installed to keep the blood vessel from recoiling. Another dye is injected to check if there are areas that require treatment. Once cleared, the catheter is removed.
Possible Risks and Complications
The success rate of percutaneous balloon angioplasty is high, offering effective symptoms relief by as much as 95%.
One of the risks involved in this procedure is the sudden collapse or closure of the dilated artery just a few hours after the procedure. This warrants immediate medical intervention as it can cause heart or renal failure.
The sudden closure of a dilated artery is often due to the presence of blood clots, weakened inner lining of the arterial wall, or elastic recoil (spasm) of the dilated artery.
To prevent the formation of blood clots in the arterial wall, patients are given a special type of aspirin (clopidogrel, prasugrel, or ticagrelor) through IV. Heparin, an anticoagulant, is also used as well as nitrates and calcium blockers to prevent blood vessel spasm that causes arterial recoil.
Medical reports show that recoil is usually observed in women, people with unstable symptoms of angina (chest pain), and those with a higher genetic risk for heart attack.
If percutaneous transluminal angioplasty fails, another medical procedure called coronary artery bypass grafting (CABG) may be attempted.
The mortality rate for post balloon angioplasty is low at just 1% making it the preferred procedure by most doctors when treating the condition.
John Hopkins Medicine; ”Percutaneous Transluminal Angioplasty (PTA)”; http://www.hopkinsmedicine.org/interventional-radiology/procedures/pta/
Daniel Lee Kulick, MD, FACC, FSCAI; “Coronary Balloon Angioplasty and Stents (Percutaneous Coronary Intervention, PCI); http://www.medicinenet.com/coronaryangioplasty/page7.htm#whatarethelong-termresultsofpercutaneouscoronary_intervention