If you are a diabetic, have been treated for coronary artery disease with angioplasty, stents or coronary artery bypass graft surgery and the signs and symptoms haven’t gone away, you may be having diffuse small vessel disease. Small vessel or coronary microvascular disease is a condition in which small arteries in the heart that are not visible in angiograms become narrowed and cause signs and symptoms of heart disease such as angina chest pain. The large vessels in the heart can become narrowed or blocked through atherosclerosis, a condition in which fatty deposits build up in the arteries. In small vessel disease, the narrowing is in the heart’s small vessels due to which they can’t expand properly when the patient is active resulting in inadequate supply of oxygen-rich blood. This inability to expand due to endothelial dysfunction may cause small vessels to actually become smaller when one is active or under emotional stress. The reduced blood flow through the small vessels causes angina or a heart attack and is usually diagnosed after a check for blockages in the main arteries of the heart show little or no narrowing in the large vessels but patient has angina symptoms. When small vessel disease is present along with large vessel disease, the condition may be suspected only when a patients has angina even after a successful angioplasty or bypass surgery.

Although anyone can have small vessel disease, it’s more common in women and in people who have diabetes, are obese, smokers, have high cholesterol, high blood pressure, unhealthy diet and inactive lifestyle. Diabetics normally feel less pain and chances of painless myocardial infarction that may go unnoticed are more. Diffuse small vessel disease is more difficult to detect and less easily treatable and if left untreated can cause coronary artery spasm, heart attack, heart failure and sudden cardiac death. When in a symptomatic patient coronary angiogram does not show blockages in larger vessels, additional tests for smaller arteries narrowing such as Stress Thallium test imaging and Cardiovascular Cartography heart flow mapping may be of help.

Because the blocked or narrowed blood vessels that cause the disease are very small, angioplasty, stent and surgery are usually not helpful. Small vessel disease treatment involves medications to control the symptoms of narrowed small blood vessels.

There has been some research on diabetic patients who have Coronary Artery Disease treated with External Counter Pulsation (ECP) therapy. ECP is an option for small vessel disease patients as it dilates the coronaries, opens dormant blood vessels and stimulates angiogenesis . An analysis of data from the International EECP Patient Registry concluded that “ECP is safe, well tolerated and associated with improvement in angina, functional status, and quality of life and that clinical benefit was maintained in most patients at one year” in diabetic patients. Patients with Coronary Artery Disease and diabetes often make excellent candidates for ECP Therapy since diabetic patients are at known increased risk for interventional complications. Reports from ECP centres suggest that patients who have undergone ECP not only have better control of their blood glucose levels but have also had their physician lower (or in some cases, completely eliminate) the dosage of diabetic medication needed to maintain an optimum blood sugar level; this is not surprising since the benefits of EECP have a similar systemic effect to that of physical exercise.

Eating a heart-healthy diet that includes plenty of whole grains, lean meat, low-fat dairy, fruits and vegetables is also good for the health. Also, watch the salt and fat intake as eating too much salt and saturated or trans-fats may increase your blood pressure and cholesterol. Regular exercise for even 30 minutes a day helps improve heart muscle function and keeps blood flowing through your arteries and prevents a heart attack by helping achieve and maintain a healthy weight and control diabetes, elevated cholesterol and high blood pressure. And last but not the least stop smoking or use of any other tobacco products totally.

About the author– Dr. S.S. Sibia, Director and Consultant, Sibia Medical Centre, Ludhiana