Shockwave Therapy: A Possible Treatment for Coronary Atherosclerosis

What is Coronary Atherosclerosis?

Coronary artery disease, or coronary atherosclerosis, is one of the most prominent heart conditions facing the United States. The disease is characterized by plaque build up in the coronary arteries, which causes the artery to narrow. This build up of plaque occurs due to excess cholesterol and fats in the arteries’ blood streams causing such substances to collect on the artery walls forming deposits. These deposits make up the plaque in the coronary arteries. Symptoms of coronary atherosclerosis include angina, cold sweats, dizziness, and heart palpitations. As the plaque build up ascends, the symptoms also become more consistent and severe. If the plaque fractures, blood clots can be formed in the arteries, which lead to heart attacks.

Non-invasive Treatments

Drugs such as statins, niacin, fibrates and bile acid sequestrants have been a common method of treatment for coronary atherosclerosis. These medications, especially statin, help decrease LDL, or low density lipoprotein, and triglycerides (bad cholesterol) and slightly increase HDL (high density lipoprotein). Further plaque development can decelerate significantly due to the effects of these medications. Although, this form of treatment cannot reverse the condition.

Aspirin and beta blockers have also been widely utilized for treating atherosclerosis. Aspirin prevents blood clots from being formed due to possible ruptures in the plaque as these blood clots may cause complete blockage of the coronary artery resulting in severe consequences. Beta blockers work as blocking agents for stress hormones such as adrenaline and noradrenaline. By preventing the action of these hormones on the heart, beta blockers impactfully reduce the activity of the heart and lower blood pressure. By lessening the heart rate and blood velocity, they lower the likelihood of plaque rupture. Additionally, beta blockers have also been linked with decreasing platelet activity in the artery walls, which would in result lower the likelihood of blood clots forming in the artery.

Nitroglycerin is also a unique medication that can be used to treat coronary artery disease. Although it does not reverse the plaque build up, it helps widen the artery to improve blood flow to the heart.

Surgical Treatments

Coronary angioplasty, also known as percutaneous coronary intervention, is a procedure used to widen the clogged artery itself. The procedure involves a balloon catheter that is placed in a coronary artery that is inflated to widen the artery walls. High inflation pressure is required for the balloon to break down the calcium in the plaques, and this high pressure can sometimes cause damage to the artery wall or even dissect the vessel. This is followed by a stent placed in the artery to keep the artery propped open and lower the likelihood of the artery becoming narrow again. The risk of stents unsuccessfully keeping the artery wide always remains eminent.

Coronary artery bypass grafting is an emergency procedure used if other methods of treatment have failed to yield positive results. The surgery helps “bypass” the blockage in the arteries by using other healthy blood vessels. This procedure is a form of open heart surgery, which necessitates a cardiopulmonary bypass machine. The surgeons use cardioplegia, which is a solution that stops the heart activity, to operate on the heart without causing damage to the entire body. In replacement of the heart, the cardiopulmonary bypass machine oxygenates and circulates the blood throughout the body. In order to replace the blocked section of artery, a section of an internal mammary artery (located in the inner chest), a saphenous vein (located in the leg), or a radial artery (located near the wrist) is removed. This section of the healthy blood vessels is known as a graft. The surgeon attaches one end of the graft to the aorta and the other end below the blockage so that there is a new path for the blood to get to the heart.

Grafts replace arteries with plaque as a new pathway for blood to flow from the aorta to the heart

The Shockwave Therapy

The new treatment technique for coronary atherosclerosis being further researched today is the shockwave therapy, which breaks down plaque similar to the way kidney stones are fractured. The therapy uses ultrasonic waves to break down hardened plaque in the arteries. A small balloon is guided in the affected arteries using a catheter, where electrodes release these waves.The efficacy of this treatment is promising as doctors are delving deeper into optimizing this technique for cardiological purposes. Studies have shown much better myocardial perfusion than from any of the other methods used against coronary artery disease. Ultrasound waves provide for a more precise and effective way of destroying plaque. Followed by the wave emission, a stent is placed to keep the artery wide allowing for proper blood perfusion. More research is currently being done on shockwave therapy before widely incorporating it into treatment for coronary atherosclerosis across the world.

Electrodes release ultrasonic waves to fracture plaque