Peripheral / Endovascular Interventions
Peripheral artery disease (PAD) is often caused by atherosclerosis, an accumulation of plaque in the peripheral arteries, which carry blood to the arms, legs and internal organs. Atherosclerosis causes the peripheral arteries to narrow and harden, and/or become blocked. By reducing the amount of blood that flows to the limbs and organs, atherosclerosis increases the risk of heart attack, stroke and transient ischemic attack. It can also cause limbs to become infected and, in severe cases, gangrenous.
Various instruments and tests are used to detect the presence of PAD. They include blood-pressure cuffs, Doppler and intravascular ultrasounds, angiograms, magnetic resonance imaging (MRI) scans and venograms.
The diagnostic test most often performed when investigating the possible presence of PAD is the ankle-brachial index (ABI),in conjunction with a Doppler ultrasound blood-flow detector. During an ankle-brachial index test, blood pressure in the leg is compared with blood pressure in the arm. The ankle-brachial index evaluates blood flow in a patient complaining of leg or arm pain, numbness, tingling and fatigue, all of which are symptoms of narrowing, hardening and blockage of the arteries. Doppler technology uses sound waves to detect blood flow, and identify any differences in blood pressure, in the arms and legs. During the arterial Doppler ultrasound, a transducer is used to detect blood flow before and after a blood-pressure cuff is inflated. Patients may experience mild cramping because the cuffs cut off circulation. ABI using Doppler ultrasound usually takes about 45 minutes to perform, and patients can return to their regular activities immediately afterwards.
After a diagnosis of PAD, other tests, including CT scans and X-rays, may be necessary to evaluate its severity, and the best method for treating it.
Coronary Interventions via the Wrist (Radial Artery)
Transradial cardiac catheterization is a procedure used to diagnose and treat conditions of the heart. During transradial cardiac catheterization, a long, thin tube called a catheter is inserted into the radial artery at the inside of the wrist; it is then guided up through the arm, into the chest and, finally, to the heart. Once at the heart, the catheter can be used to detect any blockages or abnormalities; take a blood or muscle sample; measure blood pressure and oxygen levels; detect and repair congenital heart defects; repair or replace heart valves; perform angioplasty or balloon valvuloplasty; and correct arrhythmia.
To be a candidate for transradial cardiac catheterization, a person must have a good blood supply to the hands, not only to the radial artery but to the ulnar artery (at the wrist, the ulnar runs parallel to the radial). If not, and the radial artery becomes blocked, the ulnar artery cannot take over and supply blood to the hand.
Advantages of Transradial Cardiac Catheterization
The femoral artery in the groin is the typical access point for cardiac catheterization, although transradial catheterization is used with increasing frequency, in large part because it is considered safer. Entering the radial artery through the wrist typically means that there is less bleeding at the incision site, which helps to reduce pain and the risk of infection. And when the catheter is introduced through the groin, it generally takes hours of compression to prevent bleeding. After a transradial catheterization procedure, however, the wrist needs only a small compression device.
Another considerable advantage of transradial cardiac catheterization is the quick recovery it offers. A patient is often not restricted from getting up and walking around following the catheterization. When an artery in the groin is used for access, however, the patient must lie still for several hours post-procedure to initiate healing. Using transradial catheterization also means a faster release from the hospital; depending on the type and extent of the procedure performed, a patient may be discharged on the same day as the surgery.