What’s more, in addition to losing fat mass and twice the weight, overweight coronary patients on a steady walking regimen apparently can improve their insulin sensitivity to a greater degree than people undergoing standard cardiac rehabilitation, says a new study in Circulation: Journal of the American Heart Association.
In the study, researchers at the University of Vermont randomized 74 overweight cardiac rehab patients whose average age was 64 to either a high-caloric expenditure exercise regimen, aimed at burning 3,000 to 3,500 calories a week by walking almost daily, or to standard therapy, burning 700 to 800 calories a week, exercising three times per week.
Shedding weight on a daily basis called for walking 45-60 minutes at a moderate pace -- a lower speed than standard therapy -- for five to six days per week.
The standard rehab called for walking, biking, or rowing for 25-40 minutes at a brisker pace, but only three times per week.
Five months into the study, the researchers compared the two groups and found that patients doing the daily walking had:
* Significantly greater improvement in 10 heart risk factors, including insulin sensitivity.
* A greater average reduction in weight, 18 pounds compared to 8 pounds in the standard rehab group. Walkers lost 13 pounds in body fat compared to 6 pounds for those in the standard group. And walkers’ waistlines shrunk by 2.7 inches, compared to 2 inches for the standard rehab group.
“Cardiac rehab has essentially remained the same since the 1970s because it has a mortality benefit,” says Philip A. Ades, MD, lead author of the study and a professor of medicine at the University of Vermont College of Medicine. “But it doesn’t burn many calories and things have changed. Eighty percent of our rehabilitation patients are now overweight and many of them are becoming diabetic. It’s a different time in terms of what we need to do in cardiac rehab.”
Being overweight increases the risk of heart attacks and is associated with diabetes, hypertension, and high cholesterol.
Standard rehab has benefits, but the high calorie-burning regimen increases benefits, Ades says, adding that the study’s message is “walk often and walk far.”
But he doesn’t recommend that every heart patient who’s overweight hit the streets -- not until first discussing their plans with their doctors. “We suspect that the general applicability of the high-caloric expenditure exercise programs in cardiac rehabilitation will be broad, although staff and patients will need to be comfortable with performing much of the five- to six-day-per-week exercise program away from the highly monitored rehab facility.”
Most patients continued their exercise programs after five months. A year after the study started, both groups had regained a few pounds from when last weighed. The heavy walkers regained an average of 2.9 pounds, and the lower exercisers regained 2 pounds. But weight and body fat stayed significantly lower in both groups, the researchers say.
A significant finding, and probably the most important one, was the improvement in walking patients’ insulin sensitivity as well as in multiple markers of heart disease risk (other than weight), when compared to the standard rehab participants.
The researchers’ conclusion is unequivocal: “High calorie-expenditure exercise is superior to standard [cardiac rehabilitation] exercise in accomplishing weight loss and favorably altering cardiometabolic risk factors, particularly insulin resistance, in overweight patients with [coronary heart disease].”
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The heart muscle requires a constant supply of oxygen-rich blood to nourish it. The coronary arteries provide the heart with this critical blood supply. If you have coronary artery disease, those arteries become narrow and blood cannot flow as well as they should. Fatty matter, calcium, proteins, and inflammatory cells build up within the arteries to form plaques of different sizes. The plaque deposits are hard on the outside and soft and mushy on the inside.
When the plaque is hard, outer shell cracks (plaque rupture), platelets (disc-shaped particles in the blood that aid clotting) come to the area, and blood clots form around the plaque. If a blood clot totally blocks the artery, the heart muscle becomes "starved" for oxygen. Within a short time, death of heart muscle cells occurs, causing permanent damage. This is a heart attack.
While it is unusual, a heart attack can also be caused by a spasm of a coronary artery. During a coronary spasm, the coronary arteries restrict or spasm on and off, reducing blood supply to the heart muscle (ischemia). It may occur at rest and can even occur in people without significant coronary artery disease.
Each coronary artery supplies blood to a region of heart muscle. The amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery and the time between injury and treatment.
Healing of the heart muscle begins soon after a heart attack and takes about eight weeks. Just like a skin wound, the heart's wound heals and a scar will form in the damaged area. But, the new scar tissue does not contract or pump as well as healthy heart muscle tissue. So, the heart's pumping ability is lessened after a heart attack. The amount of lost pumping ability depends on the size and location of the scar.
What Are the Symptoms of a Heart Attack?
Symptoms of a heart attack include:
* Discomfort, pressure, heaviness, or pain in the chest, arm, or below the breastbone
* Discomfort radiating to the back, jaw, throat, or arm
* Fullness, indigestion, or choking feeling (may feel like heartburn)
* Sweating, nausea, vomiting, or dizziness
* Extreme weakness, anxiety, or shortness of breath
* Rapid or irregular heartbeats
During a heart attack, symptoms last 30 minutes or longer and are not relieved by rest or oral drugs.
Some people have a heart attack without having any symptoms (a "silent" myocardial infarction). A silent MI can occur in any person, though it is more common among diabetics.
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It's called the obesity paradox, and a new review of the research shows that it is real.
Study after study has shown that obese heart patients have better survival and have fewer strokes and heart attacks than normal-weight or underweight heart patients with the same severity of disease, says cardiologist Carl J. Lavie, MD, of the Ochsner Medical Center in New Orleans.
"Even now a lot of cardiologists haven't heard of this or don't believe it," he tells WebMD. "But it is clear that as a population, obese patients with heart disease respond well to treatment and have paradoxically better outcomes than thinner patients."
Obesity Leading Cause of Heart Death
Just to be clear, no one is saying that being overweight is good for your heart. It is not.
In fact, obesity is poised to overtake smoking as the leading cause of preventable death in the U.S., and the majority of those deaths will be directly or indirectly linked to cardiovascular disease.
More than two-thirds of adults in the U.S. are now overweight or obese. Lavie says that if the trend continues the nation may soon see a decline in life expectancy for the first time in decades.
Compared to lean people, overweight and obese people have a much higher incidence of heart attacks, strokes, and death from other cardiovascular causes.
"If we could prevent obesity or limit it, it is very clear that we could reduce heart disease and deaths from heart disease," Lavie says.
But when normal or underweight people get heart disease, the studies show that their prognosis is worse than heart patients who carry extra pounds.
Lavie's review of this phenomenon encompassed research involving hundreds of thousands of patients. The findings appear in the May issue of the Journal of the American College of Cardiology.
Searching for Clues to Obesity Paradox
So if the obesity paradox really does exist in patients with heart disease, what explains it?
There are many theories, but Lavie says the answer is probably not simple.
It could be that lean heart patients have more aggressive disease because they are genetically predisposed to develop heart disease and have worse outcomes, he says.
Obese people may also be diagnosed and placed on treatment earlier in the course of their disease because symptoms closely linked to obesity -- such as becoming easily winded -- are similar to those seen with heart disease.
But there is also some evidence, mostly from animal studies, suggesting a direct protective benefit for obesity, UCLA professor of cardiology and obesity paradox researcher Gregg C. Fonarow, MD, tells WebMD.
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May 19, 2009 -- Placing bone marrow cells directly into a heart that is lacking blood flow significantly improves angina symptoms, heart function, and a patient's quality of life, a study shows.
Jan van Ramshorst, MD, of Leiden University Medical Center in the Netherlands, and colleagues say bone marrow cell therapy may be a beneficial treatment for patients with chronic myocardial ischemia, a condition that results in long-term, reduced blood flow to certain areas of the heart.
Their study is published in the May 20 edition of The Journal of the American Medical Association.
The study included 50 patients, mostly men about 64 years old, whose symptoms did not respond to conventional treatments. At the start of the study, each participant underwent a procedure to have bone marrow removed from the hip. Then, the participants randomly received either eight bone marrow cell injections or a placebo solution directly into the affected heart muscle.
Three months later, tests to evaluate heart function and blood flow revealed that the participants who received the bone marrow cells had modest improvements in blood flow to the heart muscle and in overall heart function. Specifically, magnetic resonance imaging (MRI) of the heart showed that bone marrow cell therapy led to improvements in the left ventricle's ability to pump with each contraction. (This measurement is called left ventricular ejection fraction, or LVEF.)
Those who received the bone marrow cell injections also had:
* Better scores on quality-of-life tests three and six months later
* Improvements in the ability to exercise on a stationary bicycle
A handful of studies have also looked at the effect of bone marrow cell therapy in similar groups of patients and found the therapy to be "safe and feasible," according to background information in the journal report. Other, smaller studies evaluating the effect of this treatment on patients with ischemic heart disease have had varying results.
The current study is the first randomized, double-blind, placebo-controlled trial to link bone marrow cell therapy improvements in angina symptoms and left ventricle function with a "significant improvement" in the flow of blood to the heart muscle. It is not yet clear whether these improvements will translate into better survival for the treated patients.
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