Preventing Arrhythmia A Nutritional Guide to Keeping Your Heart in Rhythm
By William Davis, MD, FACC
CoQ10 Strengthens Heart Muscle
Coenzyme Q10 (CoQ10) is found in human mitochondria, the energy-generating powerhouses of the body’s cells. CoQ10 has been in the spotlight recently because cholesterol-lowering statin drags are believed to deplete CoQ10 levels in muscle tissue, thus causing the common muscle aches suffered by many statin users.17 CoQ10 also has an effect in stabilizing cell membranes, a property that might have potential for influencing heart rhythms.18
Arrhythmias commonly occur when there is abnormal weakness of the heart muscle (as after heart attack), a viral infection of the heart, or abnormal thickening of the heart muscle, which is common in people with high blood pressure. Both situations are irritating to the heart and can make it electrically unstable and thereby generate arrhythmia.
Considerable data accumulated over the past 20 years have shown that CoQ10 supplementation can benefit people with weakened heart muscle. When 30% or more of the main contractile chamber of the heart—the left ventricle—is damaged, congestive heart failure can result. In a study of 1,715 patients conducted in Italy, daily supplementation with 50 mg of CoQ10 produced substantial improvement in ease of breathing, edema, blood pressure, and palpitations (a subjective sensation suggesting arrhythmia).19 In another large Italian study, 2,664 patients with moderate heart failure who supplemented with 50-150 mg of CoQ10 daily for three months saw similar improvements.20
In a review of nine smaller studies that sought to determine whether CoQ10 supplementation improves the strength of the left ventricular heart muscle, the pooled data suggested modest benefit.21 Whether CoQ10 reduces mortality—that is, reduces the risk of fatal arrhythmias—remains uncertain, as no study to date has specifically examined this question. Overall, however, the data are consistent in showing that people feel and breathe better, suffer less edema in the legs, experience fewer palpitations, and are able to exercise longer when taking CoQ10.
Most convincing is the evidence of CoQ10’s effectiveness in reducing high blood pressure. A literature review examining eight studies showed that CoQ10 supplementation, in daily doses generally ranging from 50 mg to 200 mg, reduced systolic blood pressure by an average of 16 mm Hg and cut diastolic blood pressure by an average of 10 mm Hg.21 Additional data from researchers at the University of Texas suggest that CoQ10 may substantially regress abnormal heart muscle thickening, or “hypertrophy,” resulting from high blood pressure.22,23 Some but not all prescription anti-hypertensive drugs achieve this desirable effect. High blood pressure and its associated thickened heart muscle underlie several varieties of abnormal heart rhythm, especially atrial fibrillation.
Only a limited number of studies specifically examine whether CoQ10 reduces abnormal rhythms, in addition to strengthening heart muscle and regressing heart thickness. In a small Indian study, participants who took 120 mg of CoQ10 daily saw a dramatic drop of 25.3% in abnormal heart rhythms during recovery from heart attack, compared to a 9.5% decline in those administered a placebo.24 In a small Japanese study examining the effects of CoQ10 supplementation in 27 subjects with high blood pressure and diabetes, 24-hour heart-rhythm recorders (known as Holter recorders) documented a substantial decrease in the frequency of irregular ventricular rhythms.25
A safe, effective nutritional agent that is virtually free of side effects, CoQ10 may help lessen
the long-term risk of arrhythmias through its actions in substantially lowering blood pressure, regressing abnormal ventricular hypertrophy, and increasing left ventricular muscle strength. It is not clear whether CoQ10 has a direct action in reducing arrhythmia or whether it simply helps correct the underlying conditions that lead to arrhythmia. CoQ10 is best used as a preventive agent to lessen the likelihood of developing arrhythmias or as an adjunct to prescribed anti-arrhythmia treatments.
Hawthorn Shows Promise
Hawthorn (Crataegus oxyacantha) is a small, native European tree whose berries, flowers, and leaves have been used therapeutically since the Middle Ages. In modern times, hawthorn has drawn attention as an aid in treating congestive heart failure. A recent meta-analysis of eight clinical trials involving a total of 632 patients affirmed hawthorn’s value in treating heart failure, with effects including diminished breathlessness and fatigue, and increased exercise capacity.26 Hawthorne has also been shown to reduce blood pressure.27 One study showed significantly fewer palpitations and arrhythmias in those taking hawthorn.27 A large clinical trial is now under way to examine whether the reduction in arrhythmia translates into better outcomes. (As noted earlier, some studies of anti-arrhythmia medication have shown that reduced rhythm irregularity does not necessarily translate into better outcomes.) Although the clinical evidence for hawthorn’s role in preventing and reducing arrhythmia remains somewhat limited, this is a promising supplement that bears watching.
Heart arrhythmia involves many complex issues that can befuddle even the most experienced cardiologists. Paradoxically, the apparently obvious strategy of suppressing abnormal heartbeats does not necessarily lead to improved outcomes.
Nutritional approaches should be used as adjuvant strategies for heart rhythm suppression or treatment. They can provide practical methods to prevent the emergence of several varieties of common arrhythmias, as well as address some of the conditions that cause arrhythmias to develop in the first place. Fish oil rich in omega-3 fatty acids, magnesium, and CoQ10 are three powerful supplements that can play a crucial role in fashioning an effective arrhythmia-prevention program.
Dr. William Davis is an author, lecturer, and practicing cardiologist focusing on coronary disease regression. He is author of Track Your Plaque, and can be contacted at www.trackyourplaque.com.
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