Cardiovascular Surgery Flashcards
What is the most common diseases, and their causes?
One of the most common diseases is atherosclerosis
- arteries narrow due to plaque
- can lead to total blockage
o blood flow to heart decreases or stops
- heart attack
How can surgical interventions can be used for treatment?
Surgical interventions can be used to remove blockage. Can be performed minimally invasive → Angioplasty
- Percutaneous procedure (through the skin)
- Cardiac catheterisation
- Through blood vessel → endovascular
Explain the procedure of cardiac catheterisation?
Needle is inserted into entry point → arteries in either arm, groin or neck.
Flexible guidewire inserted through needle and pushed up to coronary arteries. Flexible catheter inserted into blood vessel by sliding it over guidewire.
- Catheter is threaded through the blood vessel to the heart.
Pressure measured– Iodinated contrast injected through catheter once it reaches the heart. Fluoroscopy guides the cardiologist with the catheter location.
Explain the catheter lab?
Special patient table.
C-arm (Fluoroscopic Imaging).
Imaging monitors.
Supplies (catheter, guidewire).
Automatic injection pumps.
Cardiac monitors.
Vital monitors.
Explain the Needles use in cardiac catheterisation?
Needles:
- Vascular access
- Come in different sizes
- Used to insert a guidewire
Explain the use of guide wires
- Used to insert catheter
- Inserted through needle
- Stainless steel
- Wire is flexible and thin → high manoeuvrability
- Catheter is inserted over guide wire
Where are cardiac catheters placed, and what information is collected, and what do they show?
May be inserted in an artery or vein.
information is collected on the valves, chambers, and arteries, as well as the structure and function of the heart. Cardiac catheter can show a cardiologist the precise location of a blockage or defect.
Advantages of catheterisation?
- Most body parts can be reached for selective injection.
- The patient can be positioned as needed.
- The catheter can be safely left in the body while radiographs are being examined.
Procedure of insertion of catheter?
- Seldinger technique is used to introduce catheter into arteries
- Cannula used to gain access to artery
- Guide wire inserted into artery through cannula
- Cannula removed and guide wire placed over guide wire
Explain fluoroscopy
- X-ray imaging technique.
- Moving live images of patient.
- Was initially achieved by visualisation of X-rays on fluorescent screen → Fluoroscopy.
- Can be used to visualise internal structure and function of patient
- pumping of heart
- swallowing motion
- Nowadays fluoroscopic images are taken with digital equipment.
- In most catheterisation laboratories images are taken with a C-arm.
Explain the procedure of Injection of contrast agent
- Pressure injector is used to insert agent.
- 25 – 50 ml of contrast agent are injected to visualise blood vessels.
- Can also be performed manually with syringe.
Explain Angioplasty, include the risk and possible solutions?
Angioplasty is performed to dilate area of arterial blockage.
Catheter has inflatable section → balloon catheter (Balloon Angioplasty). Procedure
- Catheter is inserted as previously described
- balloon tip is inflated with saline solution
- plaque is compacted and vessel is opened up again
Risk: plaque material or blood clots might dislodge and float into cardiovascular system.
Area of blockage can close up again. This can be avoided by using a flexible metal mesh tube to keep the vessel open.
- Metal mesh tube is called stent.
Why stenting?
Stent can reduce risk of restenosis (new blockage in same area).
What equipment is used in stenting? And explain the procedure, and follow up?
Used equipment
- Balloon catheter
- Metal mesh stent
Balloon used to compact plaque and place stent.
Once stent is placed the balloon is deflated.
Additional X-ray images are taken to determine if blood flow is re-established.
What happens to the stent?
Explain the design and materials?
Stent remains in artery permanently.
Stents are made from various metals.
A wide range of designs is available for different vessel sizes and pathologies.
The selection of a stent can be based on the characteristics of the sent itself, therefore a usable grouping is required.