The American Heart Association list of top 10 research advances for heart disease and stroke in 2005 starts with the promise shown by infusing bone marrow cells into survivors of myocardial infarction to help repair damaged myocardium.
Advance number 1. German researchers found that survivors of myocardial infarction who were infused with progenitor cells from their own bone marrow had nearly twice the improvement in left ventricular function as patients given a placebo. A second study by another group of German researchers showed that implanting bone marrow cells into legs can help people with peripheral arterial disease. Patients who received the treatment walked longer distances and said their quality of life was improved.

2. The novel drug varenicline produced a two-fold increase in smoking cessation rate compared with currently used bupropion (and four-fold increase compared with placebo) when tested with roughly 2,000 smokers. Varenicline partially stimulates the brain receptors that channel the rewards associated with nicotine consumption. Smoking cessation has enormous health benefits. On average, men who smoke die 13.2 years earlier than men who don't smoke, and women who smoke die 14.5 years earlier than women who don't smoke, according to a 2004 US report.

3. The American Heart Association scientific statement on childhood obesity outlines cardiovascular consequences and suggests prevention strategies. Childhood obesity is one of the most critical public health problems today and threatens to reverse the gains of the last 50 years in reducing cardiovascular disease and death. Paralleling the weight gain of U.S. adults, the prevalence of overweight children and adolescents has almost quadrupled from 1963-65 to about 16 percent today. An overweight child is at increased risk for type 2 diabetes, elevated blood pressure, obstructive sleep apnea, cholesterol disorders and other medical problems. Psychosocial issues are also a consequence. Research shows that overweight teens seem to have fewer friends, have difficulty networking with their peers, and are more prone to commit suicide if they're teased about their weight.

The statement calls for a multi-pronged approach to preventing childhood obesity involving families, the health care system (including insurers) government agencies, the school system, the food and entertainment industries, and public health professionals.

4. Benefits of drug-eluting stents. After three years, the rate of major adverse cardiac events in patients treated with drug-eluting stents was half the rate of patients treated with bare metal stents. At six months and one year there were dramatic reductions in clinical events in patients treated with the Cypher stent. At three years the clinical event rate (which includes death, heart attack or repeat procedures) was 15.8 percent in the drug-eluting stent group versus 33.1 percent in the control group.

The Cypher stent is coated with sirolimus. The study enrolled 238 men and women, average age 60 years, with newly diagnosed blockages in a single native coronary artery. At three years, outcome data from 113 patients treated with sirolimus-eluting stents and 114 control patients were available for analysis. The dramatic difference in the adverse clinical event rate is largely due to a significantly lower rate of restenosis.

5. Disparities in cardiovascular disease care in the US were highlighted. On March 15, the American Heart Association held a news conference in New York to highlight ethnic and racial disparities featured in a themed issue of Circulation.

6. Second-hand smoke has negative consequences almost as significant as those of smoking. Compelling scientific evidence is accumulating about the substantial and rapid impact on the heart and blood vessel system from exposure to secondhand smoke. In a meta-analysis of 29 studies researchers reviewed the mechanistic effects of secondhand smoke on the cardiovascular system, emphasizing research published in the past decade.

Coronary heart disease risk in smokers increases about 80 percent compared to about a 30 percent increase in risk for passive smokers. That means passive smoking has much larger effects on the cardiovascular system than would be expected based comparing of the doses of toxins delivered to active and passive smokers, according to the study. The impact of secondhand smoke on the general public is similar to, but larger than, the effects of outdoor air pollution on the cardiovascular system. On a population basis, the effects of secondhand smoke are rapid and large. Effects on blood, blood vessels, and heart rhythm occur quickly, often within minutes.

7. Implantable defibrillators for heart failure. To decrease the risk of death, heart failure patients were randomized to receive conventional therapy for heart failure, plus an implantable defibrillator, conventional therapy plus amiodarone, or conventional therapy plus placebo.

The study, first presented at the American College of Cardiology meeting in 2004, is the largest demonstrating a survival benefit for prophylactic defibrillator implantation in patients with heart failure and depressed left ventricular function. The study included 2,521 patients with class II or class III heart failure and a left ventricular fraction of 35 percent or less. The study extended the range of patients that might benefit from prophylactic defibrillators to include non-ischemic cardiomyopathy patients and ischemic cardiomyopathy patients with reduced ejection fractions.

8. Going hot and cold can speed limb recovery in stroke survivors. In what may be the first study evaluating the effect of thermal stimulation on stroke rehabilitation, researchers found that alternating heat and cold helped rehabilitate acute stroke survivors' paralyzed upper limbs. Thermal stimulation significantly enhanced sensory and motor function in the arms and hands of stroke survivors after a few weeks of therapy. Up to 85 percent of stroke patients experience some degree of impairment in an upper limb, and recovery is often poor.

In this study, researchers enrolled 46 survivors of acute stroke. Patients received standard rehabilitation therapy for acute stroke or the standard treatment plus thermal stimulation. Members of the research team who assessed the patients' progress did not know which group received thermal stimulation. A thermal stimulation session consisted of two alternating cycles - hot/cold, cold/hot - performed five days a week for six weeks. Each session lasted 20 to 30 minutes. Each thermal pack was wrapped in two towels and placed over the patient's hand and wrist. The hot pack was 75 degrees
Celsius and the cold pack was slightly below 0 degrees C. Wrapped towels buffered thermal conduction to avoid instantaneous tissue damage.

Patients learned to move the hand of their impaired limb away from the heat or cold when they felt uncomfortable. Researchers alternated 10, 15-second heat applications with 30-seconds of no heat. After a patient's skin temperature returned to normal after the 10th heat application, the procedure was repeated with cold packs.

At the end of the six-week trial, the thermal stimulation patients had significantly greater recovery rates on four of the six measures and showed a trend to greater improvement in grasping strength and wrist extension compared to control patients. Muscle tone proved similarly in both groups.

9. Beta 2 adrenergic receptor genotype predicts survival. Researchers found that patients who had a myocardial infarction and were treated with beta blockers were more likely to survive if they had the genotype ADRB2. Researchers studied 735 acute coronary artery syndrome patients admitted at two US hospitals; 597 were discharged with beta blocker therapy. After three years, there were 84 deaths. The ADRB2 patients given beta blockers had almost twice the survival advantage from the beta blockers. Researchers said targeting beta blocker therapy may be an opportunity to
further improve care of patients with acute coronary syndromes.


10. Prehypertension triples risk for myocardial infarction. Researchers examined existing data from the Framingham Study and found that a prehypertensive person is more than three times more likely to have a myocardial infarction and 1.7 times more likely to have heart disease than a person with normal blood pressure. People with prehypertension are at much higher risk of myocardial infarction and heart disease. Prehypertension is systolic blood pressure between 120 and 139 mmHg and/or diastolic pressure between 80 and 89 mmHg.

Researchers also investigated the population's attributable risk, which determines how a disease will be affected if that risk factor were eliminated. Researchers estimated that if prehypertension was treated aggressively, 47 percent of all myocardial infarctions could be prevented. Lifestyle modifications such as weight control, regular physical activity
and changes in diet are recommended for people with prehypertension, but these findings suggest expanding these treatments for prehypertensive patients.