Coronary artery disease: bypass better than stent?
Bypass or stent? Choosing one or the other therapy for coronary heart disease is not always easy. A recent study suggests that in patients with multiple vessels narrowed, bypass surgery is superior to stenting.
Patients who had used stents of the newer generation after widening the affected arteries had a 47 percent greater risk of having to be treated for congestive arteries, having a heart attack, or having a heart attack during the course of the study, compared to patients undergoing bypass surgery to die. This was reported by the cardiologist Seung-Jung Park from the Asan Medical Center in Seoul, South Korea, together with colleagues at a cardiologist meeting in the USA. In the stent group, these events occurred in 15 percent of the patients, in the bypass group in 11 percent. "Our data indicate that bypass surgery is the best alternative for people with coronary heart disease with multiple affected vessels," said Park.
In a bypass operation, a blood vessel from another area of the body is used to bridge a narrowed or blocked coronary artery so that more blood can reach the heart. It is a major intervention. On the other hand, less invasive is angioplasty, in which a narrowed vessel is widened with the help of a balloon catheter, for example. Subsequently, a vascular support, a so-called stent, is often placed in the artery. This is to ensure that the artery remains open. Newer stents are coated and gradually release drugs to prevent blood clots. In the current study, the stents released the active ingredient everolimus.
However, the researchers restrict the statistical validity of their results. As the study was unexpectedly delayed, it had to be completed sooner than planned. The reason for this is probably that in the course of the study, a new process - the so-called functional flux reserve - had emerged. With its help, physicians can more accurately determine the condition of arteries. This leads to better results in angioplasty. In a new study, the researchers now want to compare how effective a bypass operation is compared to an angioplasty under measurement of functional flow reserve.
Bypass surgery on the beating heart
With favorable localization of the affected coronary artery, today's doctors can carry out the bypass operation on the beating heart and dispense with the use of the heart-lung machine. This may be useful, especially in older patients and in patients with comorbidities, to reduce the risk of surgery. However, this operation method requires a corresponding experience of the surgeon. When the heart surgeon opens the chest as in the conventional bypass surgery in the region of the sternum, one speaks of the OPCAB operation (off-pump coronary artery bypass). If instead he opens it laterally between the ribs, the method is called MIDCAB (minimally invasive direct coronary artery bypass) surgery. General anesthesia is also required in these procedures.
After a bypass operation, patients are monitored for one to three days in an intensive care unit. Then they come to a normal ward for about one to two weeks. Amongst other things, physiotherapists perform a bodybuilding training with the patients there. Thereafter, training and further treatment are usually continued in a three-week follow-up treatment.
What types of vascular bypasses are there?
Bypasses can be used in various parts of the body, for example, in the context of peripheral arterial disease (paVK) on the leg vessels, or in coronary heart disease (CHD) on the coronary arteries.
Most often, the coronary arteries are supplied with a bypass. To bridge the gap, doctors often use leg veins that they previously removed from the upper or lower legs of the same patient (aortocoronary venous bypass). Or they sew the end of the mammary artery on a coronary artery so that it participates in the blood supply (internal mammary artery bypass). Another possibility is the removal of arteries from the forearm (Arteria radialis bypass) in question.
In a narrowing of the coronary arteries by arteriosclerosis come in principle several treatment options in question. The doctor can either order medication only, recommend balloon dilatation (PTCA), usually with stenting, or bypass surgery. Which method of treatment the doctor and patient ultimately decide depends on several factors. In addition to age, the doctor must also consider the comorbidities of the patient (such as diabetes mellitus). In addition, it matters how many coronary arteries are affected, where the constrictions are, how severe they are, and whether cardiac function is impaired.
Often, a bypass operation is performed when the main coronary artery of the left ventricle or multiple coronary arteries are affected at different locations. The basis for the decision is usually a cardiac catheterization in advance, which represents the coronary vessels with all constrictions accurately. Afterwards, a heart team of cardiologists and cardiac surgeons usually discusses which is the best treatment alternative