Other Therapeutic Procedures
Other Interventional Cardiology Procedures
Apart from opening blocked blood vessels, other types of therapeutic procedures are performed in ACI’s Cath Labs. These include procedures to open narrowed heart valves, repair aneurysms of the aorta and prevent the movement of dangerous blood clots from the veins to the lungs, among others. These procedures are described in more detail below.
Endovascular Aortic Aneurysm Repair (EVAR) is a procedure used for the treatment of the aneurysms of the aorta. The aorta is the largest blood vessel in the body which takes blood from the heart to supply the rest of the body. An aneurysm of the aorta is a potentially fatal condition in which the walls of the aorta have become weakened resulting in an enlargement of its diameter in the affected segment of the aorta. If left untreated the aorta may rupture.
In EVAR, a cylindrical tube composed of a special fabric supported by a metal mesh called a stent graft is placed into the aorta under X-ray guidance. The stent graft is carefully positioned and anchored so as to seal tightly to the aorta at points both above and below the aneurysm, so that the blood passes through the graft rather than the affected area of the aorta. Since blood is prevented from getting to the weakened walls of the aneurysmal artery, this reduces the further bulging of the aorta and hence the risk of rupture. This procedure is not for all aortic aneurysms since it is not without risks and the interventional doctor will be able to carefully guide and advise as to whether it is appropriate for a given case. Advanced Cardiovascular Institute was the first to do this procedure in Trinidad and is arguably the most experienced centre for aortic aneurysm stenting in the Southern Caribbean.
Vena Cava Filter Implantation is a well-established procedure in which a metal filter is placed in the vena cava to prevent the migration of blood clots to the lungs. The vena cava is the largest vein in the body which takes blood from the body back to the heart and lungs. This procedure is often used to treat a condition called deep vein thrombosis, in which blood blots develop in the legs and can potentially move to the lungs where they can be fatal. The vena cava filter is implanted into the vena cava under X-ray guidance in the cath lab.
Left Atrial Appendage Closure is a newer procedure for patients with atrial fibrillation not caused by a heart valve problem (NVAF) who cannot take blood thinners. NVAF is an abnormal heart rhythm that can cause blood clots to form in an area of the heart called the left atrial appendage, or LAA. Clots from the LAA can migrate and cause a stroke and these patients have a 5 times higher risk of stroke. This risk is normally reduced by prescribing blood thinners. However many patients cannot tolerate blood thinners since they can cause internal bleeding in other areas of the body.
LAAC is a minimally invasive cath lab procedure. The doctor inserts a narrow catheter with a specialized closure device through a small puncture in a vein in the patient’s upper leg. The doctor then guides the closure device into the LAA and securely releases it. Once successfully released, the device seals off the LAAC and prevents the migration of clots. After a period of healing, a layer of tissue will form over the device and the patient can then discontinue blood thinners.
Balloon Valvuloplasty is the name of the procedure used to open valves in the heart which are narrowed and therefore not functioning properly. The narrowing is usually a result of a birth defect and the procedure is commonly performed on children, adolescents and young adults diagnosed with this problem. The procedure is similar to angioplasty in that it uses an inflatable balloon guided through a catheter into the narrowed valve. The balloon is then inflated to open the valve and improve its functionality. This procedure is most commonly recommended as the procedure of choice for treating the narrowing of the pulmonary valve.
Adult Congenital Defect (ASD and PFO) Closures
Some patients have congenital defects which result in an opening or hole between two chambers of their heart leading to the abnormal mixing of blood from one chamber with the other. Common examples are atrial septal defects (ASD) or patent foramen ovale (PFO). These birth defects can cause symptoms such as fatigue and shortness of breath and can also potentially result in a stroke. If these symptoms worsen then it may be recommended that the patient have a procedure to repair the defect.
At ACI we can do a cath lab based procedure for selected adult patients with either an ASD or PFO. Once the patient is deemed a suitable candidate by our specialist doctor, the size of the defect is measured with a specialized echocardiogram in preparation to prepare for the procedure. A catheter is inserted through a small puncture in the groin area into a blood vessel and advanced under X-ray guidance to the heart. A closure device is then advanced though the catheter and positioned in the abnormal opening of the heart. Once in position, the device is opened to close the defect and is released and the catheter withdrawn. The procedure is done under general anaesthesia and takes between 1 to 2 hours. The patient stays in the hospital overnight and is usually discharged the following day.
Other therapeutic procedures performed include pericardiocentesis and balloon pericardiotomy. These are cath lab procedures used in certain instances for draining fluid that has collected in the sac that surrounds the heart which is called the pericardial space. In a pericardiocentesis, a special needle is inserted under X-ray guidance into the pericardial space. Once in position the fluid is drained out of the body. In the balloon pericardiotomy, a special balloon catheter is guided into the pericardial space and once in position the balloon is inflated to create a channel for the fluid to drain out of the pericardial space into the pleural space where the fluid can be re-absorbed.