Treatment of angina pectoris
Treatment of angina is a multi-modality therapy, which means that a combination of lifestyle and diet modifications with drugs and even interventions may be needed simultaneously to achieve an optimal quality of life.
Management of risk factors is essential and includes:
- Control of hypertension and diabetes through medications dramatically reduces the progression of angina.
- Smoking cessation is a must for all angina patients, as the relationship between coronary artery disease and smoking is direct enough to necessitate absolute smoking cessation.
- Weight reduction is also very important. Maintaining a BMI (Body Mass Index) below the threshold of obesity (30) has a terrific effect on the outcome of angina.
- Maintaining a healthy lifestyle with regular exercise and a healthy diet. Exercises like running, swimming, or even walking tend to improve the heart’s health, prevent and help control hypertension, and even reverse atherosclerosis.
Controlling the risk factors may be sufficient in mild conditions with minimal symptoms and limitations of daily activities, but when the condition progresses and reduces the quality of life of the patient, medications and interventions become necessary.
Vasodilation is increasing the calibre of blood vessels, thus increasing blood flow and oxygen delivery to a specific organ. In angina, they act mainly on the coronaries to help supply the heart with more blood, decreasing the discomfort. The most commonly used family of drugs for this purpose are called Nitrates, and they are either taken in the form of tablets orally for long term effect or sublingually for quick relief of the angina attack. The sublingual route is so rapid that the patient observes and improvement of his condition within a few minutes. They are usually safe unless the patient has a liability to develop hypotension. Never self-medicate with nitrates, as they can interact with many drugs controlling blood pressure and those used for erectile dysfunction like Viagra.
They are a class of drugs that work by inhibiting the effect of the hormone epinephrine, leading to a slowing of heartbeats and decreasing the oxygen needs of the heart. They also lower blood pressure and help relax the muscles of the coronary arteries leading to improved blood flow.
Aspirin is an anti-platelet drug, meaning that it prevents the aggregation of platelets, thereby decreasing the risk of blood clots in the narrowed arteries. Other antiplatelet drugs may be used, as in Clopidogrel, which works by a different mechanism than aspirin, but eventually achieves the same effect.
Statins are a group of drugs that work by inhibiting the formation of cholesterol in your liver, reducing the level of circulating cholesterol in the blood, and therefore slowing and reversing atherosclerosis.
› Calcium channel blockers
Muscles need calcium to contract, and when the calcium is antagonized, it helps relax those muscles. In the case of angina, we use calcium channel blockers to help relax the blood vessels, relaxing the heart, and leading to improved blood flow to the heart muscle.
It is a relatively novel drug that acts by reducing the tension of the heart muscle, and therefore decreasing its oxygen demand. It may be used alone or in combination with other drugs, such as nitrates, beta-blockers and calcium channel blockers.
Although medical therapy with lifestyle modifications are usually sufficient in most cases, interventions, whether surgical or less invasive approaches, may be necessary in advanced cases.
Options for management in such cases include:
A. Percutaneous Coronary Intervention (PCI)
It is sometimes called angioplasty, and it involves inserting a catheter, which is a tube-like structure into your blood vessels. The usual choices are either vessel of the thigh (the femoral artery or vein) or those of the forearm (the radial artery). Afterward, the catheter goes with or against the bloodstream until reaching the heart’s blood vessels (the coronaries), the doctor then inflates a balloon at the tip of the catheter to widen the narrowed part of the blood vessel. This is usually followed by the insertion of a stent (metal or biologic mesh-like structure that keeps the blood vessels distended). The percutaneous coronary intervention has become the mainstay invasive technique in Cardiology and has largely replaced open-heart surgeries in many cases. It has much fewer complications and patients regain their normal lifestyle faster than open-heart surgeries.
B. Coronary Artery Bypass Surgery
Coronary artery bypass surgery or CABG is an open-heart surgery that is indicated in some cases of angina, as in narrowing of more than one main coronary artery or reduction of the lumen in the left coronary. As the name implies, it involves “bypassing” the narrow arteries by creating a new route for the blood instead of the narrow segment. This new route is a graft or a “piece of an artery or vein” taken from the calves (saphenous vein), forearms (radial artery) or chest (internal mammary artery) of patients. Artery grafts tend to be better than venous in terms of longevity, while veins are the most commonly used as they are easier to get and provide enough length for more than one graft. CABG surgery has the same complications of all open-heart surgeries, and therefore its use is steadily decreasing.