Angina, or angina pectoris, is chest pain due either to reduced blood flow to the heart or to certain other abnormalities of heart function.
Hardening (atherosclerosis) of the coronary arteries that feed the heart is usually the underlying problem. Spasms of the coronary arteries may also cause angina.
There are three main types of angina. The first is called stable angina. This type of chest pain comes on during exercise and is both common and predictable. Stable angina is most often associated with atherosclerosis. A second type, called variant angina, can occur at rest or during exercise. This type is primarily due to sudden coronary artery spasm, though atherosclerosis may also be a component. The third, most severe type is called unstable angina. This angina occurs with no predictability and can quickly lead to a heart attack. Anyone with significant, new chest pain or a worsening of previously mild angina must seek medical care immediately.
It is important for treatment and prevention of angina (and for overall health) to learn more about atherosclerosis.
Dietary changes that may be helpful for angina
Coffee should probably be avoided. Drinking five or more cups of coffee per day has been shown to increase the risk of angina, although effects of different forms of coffee on angina are unclear.1
Lifestyle changes that may be helpful for angina
Cigarette smoking causes damage to the coronary arteries and, in this way, can contribute to angina. It is critical for anyone with angina who smokes to stop smoking. Smoking has also been shown to reduce the effectiveness of treatments for angina.2 Secondhand smoke should be avoided as well.3
Increasing physical exercise has been clearly demonstrated to reduce symptoms of angina, as well as to relieve its underlying causes. One study found that intense exercise for ten minutes daily was as effective as beta-blocker drugs in a group of patients with angina.4 Anyone with angina or any other heart condition, as well as anyone over the age of 40, should consult a doctor before beginning an exercise program.
Nutritional supplements that may be helpful for angina
L-carnitine is an amino acid needed to transport fats into the mitochondria (the place in the cell where fats are turned into energy). Adequate energy production is essential for normal heart function. Several studies using 1 gram of L-carnitine two to three times per day showed an improvement in heart function and a reduction in symptoms of angina.5 6 7 Coenzyme Q10 also contributes to the energy-making mechanisms of the heart. Angina patients given 150 mg of coenzyme Q10 each day have experienced greater ability to exercise without experiencing chest pain.8 This has been confirmed in independent investigations.9
Low levels of antioxidant vitamins in the blood, particularly vitamin E, are associated with greater rates of angina.10 This is true even when smoking and other risk factors for angina are taken into account. Early short-term studies using 300 IU (International Units) per day of vitamin E could not find a beneficial action on angina.11 A later study supplementing small amounts of vitamin E (50 IU per day) for longer periods of time showed a minor benefit in people suffering angina.12 Those affected by variant angina have been found to have the greatest deficiency of vitamin E compared with other angina patients.13
Nitroglycerin and similar drugs cause dilation of arteries by interacting with nitric oxide, a potent stimulus for dilation. Nitric oxide is made from arginine, a common amino acid. Blood cells in people with angina are known to make insufficient nitric oxide,14 which may in part be due to abnormalities of arginine metabolism. Taking 2 grams of arginine three times per day for as little as three days has improved the ability of angina sufferers to exercise.15 Seven of ten people with severe angina improved dramatically after taking 9 grams of arginine per day for three months in an uncontrolled study.16 Detailed studies have investigated the mechanism of arginine and have proven it operates by stimulating blood vessel dilation.17
N-acetyl cysteine (NAC) may improve the effects of nitroglycerin in people with angina.18 People with unstable angina who took 600 mg of NAC three times daily in combination with a nitroglycerin transdermal (skin) patch for four months had significantly lower rates of subsequent heart attacks than did people who used either therapy alone or placebo.19
Magnesium deficiency may be a contributing factor for spasms that occur in coronary arteries, particularly in variant angina.20 21 While studies have used injected magnesium to stop such attacks effectively,22 23 it is unclear whether oral magnesium would be effective in preventing or treating blood vessel spasms. One double-blind study of patients with exercise-induced angina, however, showed that oral magnesium supplementation (365 mg twice a day) for 6 months significantly reduced the incidence of exercise-induced chest pain, compared with a placebo.24
In a controlled study, men with severe coronary heart disease were given an exercise test, after which they took either 15 grams of ribose or a placebo four times daily for three days. Compared with the initial test, men taking ribose were able to exercise significantly longer before experiencing chest pain and before abnormalities appeared on their electrocardiogram (ECG), but only the ECG changes were significantly improved compared with those in the placebo group.25 Sports supplement manufacturers recommend 1 to 10 grams per day of ribose, while heart disease patients and people with rare enzyme deficiencies have been given up to 60 grams per day.
Bromelain has been reported in a preliminary study to relieve angina. In that study, 600 people with cancer were receiving bromelain (400 to 1,000 mg per day). Fourteen of those individuals had been suffering from angina. In all 14 cases, the angina disappeared within 4 to 90 days after starting bromelain.26 However, as there was no control group in the study, the possibility of a placebo effect cannot be ruled out. Bromelain is known to prevent excessive stickiness of blood platelets,27 which is believed to be one of the triggering factors for angina.
Fish oil, which contains the fatty acids known as EPA and DHA, has been studied in the treatment of angina. In some studies, enough fish oil to provide a total of about 3 grams of EPA and 2 grams of DHA has reduced chest pain as well as the need for nitroglycerin;28 other investigators could not confirm these findings.29 People who take fish oil may also need to take vitamin E to protect the oil from undergoing potentially damaging oxidation in the body.30 It is not known how much vitamin E is needed to prevent such oxidation; the amount required would presumably depend on the amount of fish oil used. In one study, 300 IU of vitamin E per day prevented oxidation damage in individuals taking 6 grams of fish oil per day.31
Are there any side effects or interactions with angina?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful for angina
The fruit, leaves, and flowers of the hawthorn tree contain flavonoids, including oligomeric procyanidins, which may protect blood vessels from damage. A 60 mg hawthorn extract containing 18.75% oligomeric procyanidins taken three times per day improved heart function and exercise tolerance in angina patients in a small clinical trial.32
Khella is an African plant that contains spasm-relieving compounds, including khellin. Purified khellin was shown to be helpful in relieving angina in preliminary studies in the 1940s and 1950s.33 34 It is unknown whether the whole herb would have the same effects. Due to the potential side effects of khella, people with angina should consult with a physician knowledgeable in botanical medicine before taking it.
Kudzu is used in modern Chinese medicine as a treatment for angina. Standardized root tablets (10 mg tablet is equivalent to 1.5 grams of the crude root) are sometimes used for angina pectoris in the amount of 30 to 120 mg per day.
Are there any side effects or interactions with angina?
Refer to the individual herb for information about any side effects or interactions.
Holistic approaches that may be helpful for angina
People suffering from angina may find acupuncture to reduce symptoms, the need for medication, and even the need for invasive surgery. While some studies of acupuncture treatment for angina found no benefit,35 others have demonstrated positive results. An uncontrolled trial of 49 angina patients found that acupuncture resulted in 58% less nitroglycerin use and a 38% decrease in the number of angina attacks.36 In another study, 69 patients suffering with severe angina were treated with a combination of acupuncture, shiatsu (acupressure), and lifestyle changes. The results were compared to patients with severe angina treated with coronary artery bypass grafting (CABG). The incidence of heart attack and death was 21% among those treated with CABG and 7% among those treated with the combined therapy including acupuncture. In addition, 61% of those treated with the combination therapy, because of their improved health, postponed any further invasive treatment.37 In a single-blind study of 26 patients, a reduction in angina attack rate and nitroglycerin use, as well as an improvement in exercise performance, occurred in the treatment group compared to a sham (fake) acupuncture group.38 Findings from a controlled trial comparing acupuncture treatment (three treatments per week for four weeks) to placebo tablets support these results, demonstrating a reduction in the number of angina attacks, improved exercise performance, and corresponding improvements in ECG readings.39
Transcendental meditation (20 minutes twice daily of silently chanting a mantra with eyes closed) was found in a small controlled trial to reduce angina-like chest pain and to normalize electrocardiograms (ECGs) in patients with cardiac syndrome X, a form of angina in people with otherwise normal coronary arteries.40 While these patients did not have angina in the classic sense, their chest pain was thought to result from anxiety, which may reduce blood flow to the heart, and their ECGs resembled those of classic angina patients. It is not yet known whether transcendental meditation would have the same effect on patients with angina pectoris.
Evidence from preliminary41 42 43 and controlled44 studies suggests that there may be a relationship between the presence of heart disease and changes to the muscles and joints of the spine that are detectable by practitioners of spinal manipulation. In a double-blind study, patients with proven coronary disease were more likely to have specific changes in their spine detectable by palpating or “feeling” their backs than were subjects who were healthy.45 Controlled studies have demonstrated that manipulation of the joints in the middle of the neck can increase heart rate, respiratory rate, and blood pressure,46 47 but manipulation of the lower neck does not appear to have the same effect.48 Despite these intriguing findings, there is no research investigating whether manipulation reduces angina symptoms or otherwise benefits the heart and cardiovascular system.