Defibrillators save lives. And minutes count. Dr. Douglas Zipes, who is spearheading the Neighborhood Heart Watch initiative to place AEDs in communities across the country, recently heard from a colleague whose father had suffered a heart attack. Fortunately, the older man called for emergency medical assistance and collapsed only after paramedics entered his home. An AED promptly restarted his heart, and he is doing well after placement of stents and an implantable cardioverter defibrillator (ICD).

Heart attacks can trigger a chaotic heart rhythm called ventricular fibrillation and lead to sudden cardiac arrest. Unless a defibrillator is used, death follows in a matter of minutes. Symptoms of a heart attack include discomfort in the chest and other areas of the upper body, shortness of breath, cold sweat, nausea, and lightheadedness.

About atrial fibrillation

During an episode of atrial fibrillation, the upper chambers of the heart beat up to 600 times per minute.

A relatively new technique called radiofrequency ablation may be effective when medications do not slow the heart rate. In this procedure, thin, flexible tubes are snaked through the veins to the heart muscle. Then, a burst of radiofrequency is delivered to destroy the abnormal heart tissues that were producing multiple electrical signals and triggering the arrhythmias.

"The result of the ablation is that the patient is cured," said the Cleveland Clinic's Dr. Andrea Natale, a leading specialist in the treatment of abnormal heart rhythms. "Ablation is one of the few options we use in cardiology that is able to not only make the patient better, but also cure them."

More than two million Americans have atrial fibrillation. About 15 percent of strokes occur in people with the heart rhythm problem.

Lead levels and hypertension

A new study highlights the harmful effects of lead exposure. Johns Hopkins researchers report that lead levels well below current exposure standards are linked to increases in blood pressure readings in women ages 40 to 59. Blood lead levels can rise during menopause as lead is released from bones. The study is the first to document adverse health impacts as a consequence of bone lead release.

Previously, Johns Hopkins researcher Dr. Ellen Silbergeld found associations between lead and risk of death from cardiovascular disease in both men and women.

"As young children, women now in their 40s and 50s, like men, were exposed to lead from its use in gasoline, paints, and plumbing," said Dr. Silbergeld. "However, women, unlike men, run the risk of reexposures at menopause when lead is mobilized from bone back into the blood. This new study indicates that reexposure may be significant for women's health."

When stroke strikes

Women may feel the effects of a stroke differently than men do, according to a recent report in the Annals of Emergency Medicine. Researchers say that women are more likely to report headache, face and limb pain, and disorientation. Men more often experience paralysis and sudden changes in sensation, walking ability, balance, vision, and speech.

Nontraditional symptoms may be overlooked during the critical hours when stroke therapies work best. Just as with heart attack, quick treatment for stroke can save lives and minimize (or even reverse) permanent damage.