Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is a medical condition that is characterized by loss of vision on account of the blockage of the central artery of the retina. A clot from the carotid artery or the heart is usually the cause for the sudden flow of blood to the retina. Patients suffering from hypertension or carotid artery disease or diabetes are likely to suffer this condition. Arteriosclerosis is another likely cause for Central retinal artery occlusion. Due to the blockage of the retinal central artery, there is sudden and painless loss of vision. Another less severe condition is when a smaller branch artery to the retina gets blocked. This leads to loss in vision that is not as severe as in the case of CRAO.

If not attended to immediately, central retinal artery occlusion can leave a person permanently blinded. It is essential to restore retinal blood flow. An ophthalmologist may try to reduce the pressure in the eye with glaucoma agents. The embolus is moved from the central retinal artery to a branch artery. A surgical procedure whereby a small amount of fluid is drawn from the eye is carried out sometimes. This can seek to lower the pressure in the eye. Laser treatment is also done to reduce swelling and improve vision in the case of branch vein occlusion. But in most cases, it is not easy to restore normal vision.

Heart Bypass Surgery

The blood supply to the cardiac muscle is through the coronary arteries. The coronary arteries are located in the anterior and posterior locations of the heart giving a branched appearance. The width of each coronary artery is 3-4 mm and it continues throughout the cardiac muscle as small branches supplying blood to the entire heart.

Heart Bypass surgery

The cardiac muscle experiences ischemia or lack of blood supply if there is an impairment in the coronary artery. The function of the coronary artery is affected due to fatty deposits or plaque. These fatty deposits block the blood supply through the coronary artery. In this situation, the patient begins to experience chest pain and discomfort. Angina can lead to cardiac arrest if not treated immediately. The coronary artery is either partially clogged or totally clogged in these conditions. One of effective ways to treat this condition is through a surgical procedure called Coronary artery bypass graft or CABG.

The bypass procedure of the heart is an intricate and meticulous procedure involving a team of cardiac surgeons, anesthetist and perfusionist. The patient is administered general anesthesia as it is an invasive procedure. The CABG can be done in two ways, the first one involves the maintenance of circulation through the heart-lung machine operated and monitored by the perfusionist during the procedure. Here, the heart is stopped for about 30 - 90 minutes. The second one is called the Beating heart surgery or Off Pump surgery, in which the procedure is done on a beating heart. This is safer for patients who are at increased risk of complications, such as those suffering vascular disease, aortic calcifications, carotid artery stenosis or breathing or kidney problems. Other procedures are minimally invasive bypass surgery and robotic-assisted bypass surgery.

The entire CABG is categorized in two phases. In the first phase, a healthy blood vessel is taken to create the bypass near the region where the coronary artery is blocked. The graft is taken either from the arm (radial artery), chest (internal mammary artery) or legs (saphenous vein). Since there are other blood vessels connecting these tissues, it is safe to use them. Depending on the location, amount and size of the blockage, the choice of substitute blood vessel is made. In the second phase, the surgeon creates the bypass route from the clogged site of the coronary artery to generate a healthy supply region for the cardiac muscle. The duration of the procedure ranges from 3-6 hours depending on the number of grafts the patient requires. Patients are transferred to critical care units after surgery and generally kept under admission for a period of six to nine days.

Postoperative care in CABG

The risk factors associated with the CABG procedure include heart rhythm problems, kidney or lung failure, chest wound infection and memory malfunction. Postoperative care plays an important role in retaining the normal function of the heart. Patients notice a swelling at the site of incision which gradually subsides after a few weeks. Postoperative experience in CABG requires rehabilitation as many patients complain of anxiety, lack of sleep and anorexia. Patients are advised to abstain from activities such as heavy lifting, driving and climbing stairs. Cardiac rehabilitation techniques aid the patients in improving their cardiac endurance levels and also creating an optimistic mind set after surgery. Medication and exercise in moderate levels subsequently improve the functionality of the heart; however patients are advised to avoid foods containing trans-fats and smoking.

Angina

Angina or chest pain is a typical symptom associated with coronary artery disease. Angina is a sign that the heart is not getting sufficient blood flow. This is usually due to narrowing of the arteries (atherosclerosis. It can also be the result of extreme hypertension, hypertrophic Cardiomyopathy or valvular heart disease. Stable angina is a pain that occurs when there is extra load on the heart and occurs in a regular pattern. This type of angina pain can be tackled with medication and rest. On the other hand, unstable angina can be dangerous as it may the precursor to a heart attack. The pain in such a case is more prolonged and severe. Prinzmetal's angina or variant angina pectoris occurs due to transient spasm of the coronary artery. This does not get triggered due to physical exertion.

The pain associated with angina is uncomfortable pressure and squeezing on the chest. There is pain or discomfort in the neck, shoulder and arms. But not all chest pains are signs of angina. ECG (electrocardiograph) helps in tracing heart activity. Exercise-ECG assesses your heart condition when you are on a treadmill. Beta-blocker drugs help prevent angina pain. Potassium channel blockers and calcium channel blockers aid in improving blood flow to the coronary arteries. Glyceryl Trinitrate or GTN tablets work instantaneously by relaxing blood vessels and easing the blood flow to the heart muscles. Aspirin is prescribed to reduce the probability of blood clots and reducing blood viscosity. Statin medicines are prescribed to reduce cholesterol levels. Angioplasty involves passing a tiny balloon into a large artery and then blowing it up inside to widen the artery. Bypass surgery is done to bypass the narrowed section of arteries and provide the heart with blood vessels that are not obstructed. Angina can be controlled with medication and lifestyle changes in diet and exercise.

• Quit smoking
  
• Control cholesterol levels
  
• Control blood pressure levels
  
• Regular exercise regimen
  
• Nutritious diet - low in fat, high in fibers, rich in fruits, vegetables and oily fish
  
• Maintain healthy body weight