Difference Between Stent and Catheter

Main Difference – Stent and Catheter

Stent and Catheter are two medical or surgical tools which are used for various treatment purposes with the ultimate intention of lifting up a patient’s quality of life . These medical terms are often used interchangeably, mainly due to lack of knowledge. The main difference between stent and catheter lies in their objective; a stents are used to restore the blood circulation, support the inner wall arteries and prevent bursting of arteries whereas catheters are used to deliver medication, fluids or gases and to drain fluids in the body.

This article discusses,

1. What is a stent?
– Features, Use, Purpose, Procedure and Risks

2. What is a Catheter?
– Use, Purpose, Types

3. What is the difference between Stent and Catheter?

What is a Stent

A stent is a narrow and mesh-like tube which is used inside weakened and narrowed blood vessels to restore the blood circulation, support the inner wall of arteries and prevent bursting of arteries in the system.

These are usually made up of metal and highly durable; fabric-made stents have also been introduced lately, for larger arteries.

Stents are usually placed inside a blood vessel by a technique known as percutaneous coronary intervention (PCI). This special intervention is usually carried out in patients with narrowed or blocked arteries in cases such as coronary artery disease (due to formation of waxy structures in the arteries which supply blood and oxygen to your heart), carotid arteries disease (due to the same pathological structures developed in the blood vessels supplying your brain), renal artery diseases and peripheral artery disease (PAD).

Other incidents where stents are inserted into blood vessels include

Abdominal aortic aneurysms
Tears on the abdominal aorta

How are Stents Placed

Firstly, the surgeon will make a small opening in the blood vessel around the area of the upper thigh, arm or neck and a thin flexible tube with a balloon attached to the tip (catheter) will be inserted through that hole into the artery. The stent which is placed around the deflated balloon will be set-up in the narrowed or blocked blood vessel, in order to keep it wide open. Special X-ray sequences taken while the procedure is been carried out will help the doctor to find the exact position of the stent.

This overall procedure will help in the restoration of blood flow in the blood vessels, thus reducing the possibility of features of angina and other coronary heart diseases.

The stent is supposed to support the inner wall of the artery, thereby reducing the incidence of getting it blocked or narrowed again. Therefore, unless the artery is really small, it will generally be placed only in the PCI-treated portion during the same time of the intervention.

As far as the success rate of this stent placement (PCI) is considered, there will be a 10-20% chance of getting a narrowing or blockage, but it is highly recommended to carry it out as soon as possible since putting PCI aside can increase the overall morbidity by 10-15 times.

Possible Risks Associated with Stents and PCI

Stents

Blood clots resulting in heart attacks, stroke

PCI Procedure

Bleeding from the site of insertion of the stent
Damages to the surrounding blood vessels
Arrhythmias (irregular heart rhythm)
The dye used to identify the position of the stent might have a negative effect on kidneys in some patients.
Allergic reactions to the dye
Introduction of infections through the site of insertion
Re-stenosis

What is a Catheter

Catheters are medical instruments which are used to deliver medication, fluids or gases and to drain fluids in the body like urine. They are usually inserted into a body cavity, blood vessel or a duct. Catheters are categorised into soft (soft and flexible) and hard (thick and non-flexible) types depending on the nature of the material used.

Commonly used Catheters

Intravenous Catheters – administer drugs (insulin pumps, chemotherapy)
Urinary Catheters
Chest drainage tubes
Foley’s Catheter – one of the commonest types of catheters, which is inserted and placed inside the bladder with the help of a balloon inflated with sterile water. Urine will drain via the catheter into a special bag which can be detached and emptied when necessary. This type of a catheter is used for patients with urine retention, disturbances in maintaining a proper stream of urine, obstructed urethra or to monitor urine output following surgery.
Central Venous Catheters – a comparatively larger catheter type which is directly connected to large veins in the neck or atrium in order to administer drugs and fluid. This method is usually used in unstable patients who need to get resuscitated.
Umbilical Catheter – This is used in sick newborns in order to deliver medication and fluids.
Catheters used in cardiovascular procedures such as Angioplasty, balloon septostomy,
Catheters used to administer epidural and spinal anaesthesia
Quinton Catheters – Used for patients undergoing dialysis
Another type of catheter is used to drain fluid and pus, formed inside cavity abscesses. g. Abdominal abscess
Foley catheter

A stent is either a metal or plastic tube which is inserted into a blood vessel, cavity or a duct of the body in order to keep the lumen and the passage wide open.

A catheter is an instrument which is used to deliver or drain fluids from blood vessels or body cavities. This is the main difference between stent and catheter.

Both these instruments play important roles in hospital and clinic settings, but the usage may differ according to the condition of the patient.

Image Courtesy:

“Blausen 0034 Angioplasty Stent 01” By Blausen.com staff. “Blausen gallery 2014”. Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762. – Own work (CC BY 3.0) via Commons Wikimedia

“Foley catheter inflated and deflated EN” By Olek Remesz (wiki-pl: Orem, commons: Orem) – Own work (CC BY-SA 3.0) via Commons Wikimedia