Coronary Artery Bypass Surgery (Cabg)

The coronary artery bypass surgery (CABG revascularization) relates native coronary arteries with high grade stenosis or occlusion, which are not suitable for angioplasty with stent delivery. The indications are constantly changing, as the percutaneous interventions are increasingly being used. Traditional CABG procedures to a traditional coronary arteries bypass surgery includes a thoracotomy with median sternotomy. A heart-lung machine is used to establish cardiopulmonary bypass (CPB), so that the heart be stopped and can be emptied of blood, in order to maximize exposure and operative to facilitate vascular anastomosis. The stopping of the heart reduces oxygen demand. Before the start of CPB to the patient a very high dose of heparin given to prevent blood clotting in the bypass circulation. After that, the aorta is clamped and the heart by injecting a cardioplegia solution (krystalloid or frequent blood-based), which also contains substances that help the heart muscle cells going to tolerate ischemia and reperfusion stopped. The cardioplegia solution and the heart are sometimes cooled slightly, to increase the ischemia. The patient’s body is cooled by the CPB machine for similar reasons. The left internal mammary artery is typically set as a pedicled bypass to the left anterior descending artery. Other bypass modes consist of sections of the saphenous vein, which are taken from the leg. Occasionally, the right mammary artery or artery can be used radialis of the non-dominant arm. After completion of the vessel anastomoses the aorta is unclamped so that the coronary arteries are perfused by oxygenated blood, which typically restores the heart activity. The heparin anticoagulation is reversed by protamine is added. Despite cardioprotective measures is the stopping of the heart is not without consequences. During reperfusion myocardial dysfunction is common and can lead to bradycardia, arrhythmias (z. B. fibrillation) and low cardiac output lead. These events are treated with standard measures such as pacing, defibrillation, and inotropic drugs. Typically, the hospital stay is 4-5 days, unless it is extended by complications or concomitant disease. Complications of coronary artery bypass surgery complications and disadvantages of the traditional CABG mainly include sternotomy cardiopulmonary bypass median sternotomy is surprisingly well tolerated. However, the healing process takes 4-6 weeks. Also cause wound infections occasionally mediastinitis or osteomyelitis sternale that can be difficult to treat. CPB causes several complications, including bleeding organ dysfunction Neuropsychiatric effects stroke an bleeding after CPB is a common problem that is caused by various factors, including hemodilution, heparin use, platelet dysfunction due to the exposure to the bypass pump, disseminated intravascular coagulation and induced hypothermia , Organ failure can be by a systemic inflammatory reaction – caused by the CPB machine – occur (presumably due to the exposure of blood components with respect to the extraneous material of the bypass circuit). This reaction can cause (z. B. lungs, kidneys, brain, GI) organ failure in each system. Aortic cannulation, -Abklemmung and -Entklemmung to the release of emboli that lead at about 1.5% in a stroke trigger. Microembolism may cause neuropsychiatric effects after CPB that occur at about 5-10%. Other common complications of CABG are focal myocardial Global myocardial ischemia Dysrhythmias Perioperative myocardial infarction occurs in about 1% of patients. Atrial fibrillation occurs in 15-40% of patients, typically 2-4 days after surgery. Beta-blockers (including sotalol) and amiodarone seem to reduce after heart surgery, the likelihood of developing atrial arrhythmias. A non-sustained ventricular tachycardia may occur in up to 50% of patients. Mortality depends primarily on the underlying health condition of the patients. Operator and institutional experience (d. E., The number of annual procedures) are also important. In an experienced program periprocedural mortality in otherwise healthy patients is typically <1-3%. A simple calculator can categorize (low, medium, high) the risk of CABG in three groups. An advanced online calculator for the heart risk is published by the Society of Thoracic Surgeons. Clinical Calculator: Euro Core for Risk Assessment of Cardiac Surgery (additive Version) Alternative CABG procedures Newer techniques attempt the complications of traditional coronary artery bypass surgery (CABG) limit by avoiding cardiopulmonary bypass (off-pump CABG) avoiding median sternotomy (minimal -invasive CABG) Both off-pump CABG A cardiopulmonary bypass can in selected patients through the use of techniques can be avoided, allowing the surgeon to revascularize the beating heart. Various devices and methods to stabilize a portion of the myocardium, whereby the operative site is kept relatively motionless. Off-pump CABG procedures are often performed by small parasternale or intercostal incisions (minimally invasive CABG), sometimes with endoscopy or robot support, but they can be made by a traditional median sternotomy, which provides a better operational exposure. If the heartbeat approved, it means that the heart muscle needs more oxygen than if CPB is used. Thus, the heart is sensitive to the interruption of blood flow, which is necessary during vascular anastomosis is performed. This break may ischemia or infarction in the heart muscle, which is supplied by the affected vessels, cause. Some surgeons place a temporary coronary artery shunt to distal perfusion to gewährleisten.Minimal invasive CABG Minimally invasive CABG technique is more difficult to perform and may not be suitable if several bypasses, in particular those concerning the vessels behind the heart, required are. Transfusion requirements, length of stay and costs are typically lower in off-pump CABG, but in some studies are similar to the rates of serious complications death, myocardial infarction and stroke those of CABG with CPB. Thus, the theoretical benefits of avoiding CPB were apparently not fully realized. Minimally invasive CABG is usually carried out with off-pump procedure, but can be done using CPB. In such cases, CPB is performed endovascularly, using special catheters, which are inserted into the arterial and venous systems. The aorta is occluded by a balloon at the end of the aortic rather than by an external brace. Although the median sternotomy complications are avoided, this technique has otherwise similar mortality rates and priority perioperative complications such conventional techniques.

Health Life Media Team

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