"There's still a long way to go before the biologic pacemaker is ready for prime time. But 2002 marks the year that researchers showed 'proof of concept,'" noted Dr. Bonow.

Reference: Nature, September 12, 2002.

2. Study findings show that devices can definitely improve clinical outcome for selected patient groups.

First, implantable cardioverter defibrillators reduce the risk of sudden cardiac death secondary to damage from myocardial infarction or heart failure. In the twenty-month study of 1,232 such patients, the mortality rate was 20 percent for patients who were not given a device compared with 14 percent for patients who were given one - a 31-percent reduction in mortality.

A second research team reported that an enhanced pacemaker that synchronized contraction of the left and right ventricles could prevent many patients with congestive heart failure from symptomatic progression or death. The device has been on the market since 2001. In the six-month study of 450 patients, those implanted with the InSync device walked further, exercised longer, and generally felt better. Medtronic Inc., maker of the device, funded the study.

Reference: American College of Cardiology's Scientific Sessions, 2002.

3. A refined angioplasty technique that includes use of a small filter to catch loose bits of atherosclerotic plaque may offer an alternative to carotid endarterectomy. Researchers organized a clinical trial with 307 patients: About half had a standard carotid endarterectomy, whereas the remainder underwent angioplasty.

At 30 days, the rate of death, myocardial infarction and stroke was about 50 percent less in patients who underwent refined angioplasty (5.8 percent) compared with the rate in patients those who underwent carotid endarterectomy (12.6 percent).

To test the filter approach, the researchers employed an experimental device dubbed Angioguard, made by Johnson & Johnson, which funded the study. During angioplasty and stent placement, the filter opened like an umbrella beyond the area being treated. When the procedure was completed, the filter was closed, trapping debris inside, covered with a tiny sheath, and removed.

Reference: American Heart Association's Scientific Sessions, November 2002

4. Cardiovascular risks of hormone replacement therapy are found to outweigh the benefits, causing the Women’s Health Initiative trial to stop. Early analysis suggested that hormone replacement therapy raised the risk of stroke by 41 percent, of myocardial infarction by 29 percent, and of breast cancer by 26 percent, all compared with placebo.

Because the actual number of events was so small, six to eight excess strokes, myocardial infarctions, or breast cancer cases could be detected in 10,000 women per year of treatment. There was a decrease in colorectal cancers and hip fractures, but the overall increase in risk made it clear that women should not take combined hormone replacement therapy to prevent cardiovascular disease.

The study followed 16,608 postmenopausal women aged 50 to 79 years. Researchers did not find that women taking replacement therapy were more likely to die than women who took a placebo, but the study was stopped after the women had taken the drugs for just over five years.

Reference: Journal of the American Medical Association Express July 17, 2002

5. Death rates were found to be lower in hospitals that follow treatment guidelines for myocardial infarction than in those with low adherence to the guidelines.
Patients treated in hospitals with low adherence had a one third greater risk of inhospital death than patients treated at hospitals with the highest overall adherence to guidelines (mortality rates of 17.6 percent and 11.9 percent respectively).

The study was one of the first to examine variation in treatment and patient outcomes.
Nationally marked variation in the U.S. was found in treatment for patients with myocardial infarction, even for well-accepted standards of care.

Reference: American Heart Association's Scientific Sessions, November 2002.

6. Obesity was found to be a strong and independent risk factor for heart failure when researchers followed 5,000 participants in the Framingham Heart Study for 15 years. After adjustment for known risk factors, obese women were twice as likely to develop heart failure as normal-weight women, and obese men had a 90-percent increased risk.

With each increase of 1 in body-mass index, a man's risk of heart failure
increased 5 percent and a woman's risk increased by 7 percent.

Reference: The New England Journal of Medicine, August 1, 2002.

7. Two large trials on atrial fibrillation published in 2002 concluded that a much simpler and less expensive approach (termed rate control) is at least as effective as rhythm control in prevention of mortality. Rate control uses drugs such as beta-blockers to suppress heart rate and symptoms.

In the Atrial Fibrillation Follow-up Investigation in Rhythm Management (AFFIRM) trial, 4,060 patients were randomized to rate control or rhythm control. At an average follow-up of 3.5 years, there was a trend toward fewer deaths in the rate-control group (306 versus 356), but the difference was not statistically significant. The number of strokes was nearly the same in both treatment groups, and fewer hospitalizations were required for the rate-control group.

The Rate Control versus Electrical Cardioversion for Persistent Atrial Fibrillation (RACE) study showed similar results. However, adverse events were more common in the rhythm-control group, particularly in patients with hypertension.

Both trials confirmed the importance of anticoagulation to reduce the risk of stroke in patients with atrial fibrillation.

Reference: New England Journal of Medicine, December 5, 2002.

8. Cell transplantation therapy was found to strengthen hearts. Several teams of researchers showed that transplanting cells from patients' thigh muscles
or bone marrow into necrotic or weakened heart tissue during reperfusion treatment for patients with myocardial infarction or heart failure may have the potential to replace scar with viable muscle tissue.

In the first human testing in the United States, doctors studied 13 patients who had a history of myocardial infarction or heart failure and whose left-ventricular ejection fractions were less than 30 percent. The patients' myoblasts were extracted from thigh muscle and grown into larger quantities in the laboratory for three to four weeks. During surgery, three to thirty direct injections of thigh muscle cells were made into the damaged myocardium.

Interim results showed that transplanted cells remained viable inside the heart. No significant adverse reactions were found related to the cell transplant procedure in either group of patients nine months later. On average, ejection fractions improved from 22.7 percent to 35.8 percent after 12 weeks. The improvement might have been related to the underlying procedure.

Although the trial was not designed to evaluate the effect of cell transplant on cardiac function, the results indicate that at least the procedure is safe and feasible.

A British team obtained similar results with use of bone marrow cells taken from the sternum rather than myoblasts. The researchers also studied patients who had low ejection fractions following myocardial infarction. They reported that bone marrow cells transplanted into the heart enhanced cardiac function - a benefit that was evident just six weeks after transplantation and maintained at ten months of follow-up. In their procedure, marrow was injected directly into scar tissue identified during non-emergency coronary artery bypass surgery.

A third, German, group also reported evidence of improved revascularization in areas of the heart that were transplanted with a person's own bone marrow stem cells.

Reference: American Heart Association's Scientific Sessions, November 2002.

9. Robotically assisted cardiac surgery successfully corrected congenital atrial septal defect without cracking open the chest. The minimally invasive procedure required four small incisions made under the guidance of a surgeon seated at a high-tech console a few feet away from the patient. Two robot arms threaded tiny surgical instruments through two of the incisions. A camera-like device was inserted through the third hole, and a human assistant passed surgical materials through the fourth hole.

Researchers reported results for 15 patients, ages 22 to 68 years, who underwent repair using the robotic technology, called the Da Vinci (TM) system. The
procedure was completely successful in 14 of the 15 patients. One required a
repair five days later. There were no major complications. The average hospital stay was two to four days shorter than for traditional surgery and patients returned to normal activity about 50 percent faster than would have been expected.

Doctors are also using robotic technology to repair mitral valve defects through incisions in the side of the chest and for closed-chest coronary artery bypass surgery.

Reference: American Heart Association's Scientific Sessions, November 2002.

10. The largest study of hypertension, the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), found that diuretics were better than some newer, more expensive medications as first-line treatment for hypertension. The trial involved 42,418 participants aged 55 years and older. Participants had hypertension (140/90 mm Hg or higher) and at least one other risk factor for heart disease.

Compared with the diuretic, the calcium channel blocker resulted in about
a 1 mm Hg-higher systolic blood pressure, a 38-percent higher risk of heart failure and a 35-percent higher risk for hospitalization.

Compared with the diuretic, the angiotensin converting enzyme inhibitor resulted in about a 2 mm Hg-higher systolic blood pressure (4 mm Hg higher in African-Americans), a 15-percent higher risk of stroke (40 percent higher for African-Americans), a 19-percent higher risk of heart failure, an 11-percent greater risk of hospitalization or treatment for angina, and a 10-percent greater risk for a coronary revascularization procedure.

Reference: Journal of the American Medical Association, December 18, 2002