Bypass surgery for clogged arteries can increase SCA risk, but the danger often drops significantly as the heart heals. As a result, doctors who specialize in heart rhythms (electrophysiologists) wait three months to treat patients with an implantable cardioverter defibrillator (ICD).

“With the current treatment guidelines, there is a window of time during which someone at risk may not be protected—and that’s when we recommend the Zoll LifeVest,” explains electrophysiologist Krishna Malineni. “When the vest activated, it proved what we had suspected—Mr. Dalrymple had a permanent need for an ICD and we promptly provided him one.”

Heart patients waiting for transplants or being treated for infection-related heart problems are also potential candidates for LifeVest, which is covered by most health insurance plans.

Unlike Mr. Dalrymple and other heart patients, however, most of the 400,000 Americans stricken by SCA every year have no idea they are at risk for the tragic event. Click here to read more about sudden cardiac arrest and ongoing research to better identify those at risk, as well as what to do when SCA strikes.

A Life Vest for the Heart The Saturday Evening Post

AEDs are computerized devices that check a person’s heart rhythm and deliver a shock to restore a heartbeat, if needed. Odds of surviving SCA drop about 10 percent every minute that a shock is not received.

“I like the analogy of AEDs and fire extinguishers,” says Dr. Page. “It’s unthinkable to not have fire extinguishers or smoke detectors in public places. When I give lectures about AEDs, I can usually spot a fire extinguisher nearby. But in many cases, I have not seen an AED on my way to the podium.”

Post: When were portable defibrillators first used in the U.S.?

Dr. Page: They were introduced in the 1990s, and American Airlines began putting defibrillators on aircraft in 1997. I was at the University of Texas Southwestern Medical Center in Dallas at the time. We worked with American Airlines and I reported the experience in the New England Journal of Medicine. A study of AEDs in casinos was conducted at the same time and those results appeared back-to-back with the aircraft article. In 2000, the American Heart Association named the AED one of the top 10 cardiac research advances. It’s gratifying that AEDs are being placed in more and more venues. But it’s distressing that they aren’t everywhere yet.

It is important to note that AEDs are automated external defibrillators rather than automatic external defibrillators. People get this wrong all the time. There is a wearable vest defibrillator that automatically gives a shock for SCA.  But the AEDs in health clubs, hospitals, police cars, aircraft, and casinos are automated, not automatic. These devices will not deliver a shock until the human operator pushes a flashing red button.

Post: Who can use a portable defibrillator?

Dr. Page: I think anyone can. Some states require authorization to use these devices, and I support the American Heart Association’s efforts to train the public. But the simplicity of these devices was demonstrated by investigators in Seattle, who did a small study with mannequins, 6th graders, and paramedics. They instructed the 6th graders (who had no prior experience with an AED) to figure out the device and save the life of a mannequin. Results published in the journal, Circulation, one of the best heart journals, showed that 6th graders delivered a shock in 92 seconds. Well-trained Seattle paramedics accomplished it in 60 seconds. So it is better to be trained, but almost anyone can figure out how to use an AED.

Training is important, but if I had a cardiac arrest and no one knew how to use an AED, I’d much rather that a bystander try to figure it out than wait 10 minutes for an ambulance to get to me. In the casino experience, a setting in which every arrest was videotaped, three out of four victims survived if they were shocked within three minutes. In contrast, less than one in 20 survives SCA in most cities.

Post: What about “no-hands” CPR?

Dr. Page: I was one of the co-authors that issued the AHA scientific advisory statement in 2008 recommending compression-only CPR for adults who experience sudden cardiac arrest outside of the hospital. The advisory group and the American Heart Association have gotten behind the idea of hands-only CPR.

This makes sense for many reasons. For example, if I have sudden cardiac arrest right now, I have plenty of oxygen in my blood—what I need is circulation. We know from some very important research in animals and in humans that in CPR you need to pump hard, fast, and continuously to maintain blood pressure. After every pause in chest compression, you have to work to build up the blood pressure again. Mouth-to-mouth breathing probably isn’t necessary. Chest compressions actually move some air, too.

Post: Can someone be sued for using an AED if the victim dies or gets brain damage?

Dr. Page: Probably not, because every state has Good Samaritan laws in place. The operator has almost no liability risk, as long as he or she is operating in the best interest of the individual.

Post: You mentioned earlier that these devices are more accessible, but there aren’t enough of them. Why is that?

Dr. Page: One challenge is public awareness, getting the word out. Another is a mistaken concern about liability, as we’ve discussed. And finally, cost is an issue. If AEDs cost the same as fire extinguishers or smoke detectors, we would have more of them out there. I don’t generally support AEDs in homes because the overall likelihood of one being used is so small that our health dollars would probably be better served in other ways.

Post: Even though most sudden cardiac arrests happen at home?

Dr. Page: Yes. The problem is that many of these events occur when the person is asleep or alone, so having an AED would be of no benefit. Although a home AED would not hurt, and some people elect to purchase these, I am primarily interested in campaigns to place AEDs in more public places.

Post: If people are interested in doing something like that, where do they start?

Dr. Page: They can contact the Heart Rhythm Society or the American Heart Association for advice. The Heart Rhythm Society has advocated strongly on behalf of patients at risk for and who have experienced cardiac arrest, and we maintain an active Web site. Area physicians may also be a good resource for grassroots campaigns and local champions.

Post: What do you expect might be the next breakthroughs in preventing SCA and saving lives?

Dr. Page: I envision two avenues. One is better identification of those individuals who are at the highest risk for SCA and would benefit most from an ICD to modify that risk. The second (because we won’t identify everybody at risk) is to increase awareness of SCA, improve accessibility to AEDs, and increase the number of people who are trained in CPR and AED use.

I’ll tell you an interesting story that occurred while Charlie Jones, Heart Rhythm Society Vice President of Marketing, Communications and Membership, and I were visiting a number of media outlets on the east coast. After we landed in D.C. and were driving away from National Airport, Charlie noticed something unusual by the side of the road and said, “I think someone’s down there.”

We stopped, and there was a man in his 50s who had experienced sudden cardiac arrest while jogging along the road. Bystanders were already doing two-person CPR with beautiful respirations, so I didn’t interfere with that other than to take my turn at chest compressions. Occasionally the victim would make a gasping breath and people said, “Oh, he’s breathing, let’s stop.” But I said, “No, no, keep going” because I knew the gasping breath was a brain stem response, not a conscious one. When the ambulance arrived with the AED, a single shock was delivered. One shock, and he had been down probably 15 minutes or more! He awoke and actually gave us a thumbs-up when he got in the ambulance.

Isn’t that amazing? The experience reminded me that CPR, when well performed, pumps blood well to the heart and brain. CPR can keep someone alive until the person gets that lifesaving shock from the AED. Being familiar with CPR and AEDs really does save lives.

Click here for Part 1: Understanding SCA. 5 facts about sudden cardiac arrest and heart attack.
Click here for Part 2: Preventing SCA. Are you at risk?

Curing SCA with Defibrillators and No-Hands CPR The Saturday Evening Post

Preventing Sudden Cardiac Arrest

Every two minutes, someone collapses and dies from a malfunction in the heart’s electrical system—a condition called sudden cardiac arrest or SCA—and most of the victims have no idea they are at risk for the tragic event.

“That’s absolutely true,” says Dr. Richard Page, immediate past president of the Heart Rhythm Society and chair of the Department of Medicine at the University of Wisconsin School of Medicine and Public Health. “While a single individual’s chance of dying suddenly is quite small, there are so many people out on the street with some risk that the overwhelming majority of SCA victims have not ever demonstrated cardiac disease.”

The challenge for SCA researchers is two-fold, according to Dr. Page, who recently took time to discuss with us the latest findings on SCA risk factors and symptoms, as well as advances in preventing the heart emergency and saving lives.

“It comes down to two questions,” explains the heart rhythm specialist. “How can we better identify those at risk? And, given the fact we can’t identify all (or even most) of the potential patients: How do we address sudden cardiac arrest when it does happen?

Post: About 250,000 Americans die of sudden cardiac arrest every year. Who is at most at risk?

Dr. Page: Ongoing research confirms that heart structure is an important risk factor. People with an enlarged heart, or heart damage from a prior heart attack, are at higher risk for SCA than those with normal heart structure.

Remember, a heart attack isn’t a sudden cardiac arrest; a heart attack is death of heart tissue due to a blockage in an artery. A person who has a heart attack doesn’t lose consciousness, unless they have a cardiac arrest on top of that.

But it is clear from large, multi-center, randomized studies that many patients with prior injury to the heart or enlargement of the heart are better off with an implanted cardioverter defibrillator (ICD) than without one.

More recently, we have identified certain families who are at higher risk because of cardiomyopathy (a condition in which the heart is enlarged or thickened) or an electrical abnormality called long Q-T syndrome that can be seen on the EKG test. In addition, investigators are identifying the genetic abnormalities that underlie these conditions, as well as some genetic traits that may put one at higher risk of sudden cardiac arrest that are less subtle than abnormal heart structure or function.

Post: Is genetic screening for SCA risk available yet?

Dr. Page: Genetic tests for the general population are not ready for primetime because the genes don’t predict risk adequately. An abnormal EKG, for example, may or may not represent a significant risk to the individual. But we may have genetic tests for general screening five or ten years from now.

Likewise, there continues to be some debate as to the proper way to screen athletes. In Europe (particularly in Italy) everyone who participates in sports is screened with an electrocardiogram. The American Heart Association doesn’t yet recommend that. But they do advise that people be examined and asked about personal and family history. If someone has family members who died suddenly, he or she is clearly at higher risk for SCA and should be evaluated further.

Post: You mentioned that Italy recommends EKGs. Don’t we use echocardiograms (Echos) to screen U.S. athletes?

Dr. Page: We do both in some cases—but according to the risk. The most aggressive method of screening athletes is an exam, a history, an EKG, and an Echo. The echocardiogram defines heart structure. It provides a two-dimensional moving picture that shows chamber size and wall thickness. An EKG provides indirect evidence of structure. For example, alterations in electrical activity may suggest hypertrophy, or a prior heart attack. It doesn’t necessarily tell you if the heart is enlarged or damaged the way an Echo does, but it’s a simple and less expensive test.

Another point about universal screening: Some might say, “Well, let’s just screen everybody.” Well, the problem is that the tests aren’t perfect. If you screen a low-risk population, there will be some false positive results. I am concerned that the Italian protocols have excluded too many athletes. So universal screening of athletes might cause undue concern, and even cause some athletes at low risk to stop competing. Universal screening of low-risk individuals is a double-edged sword.

Are there any symptoms or warning signs of SCA?

Dr. Page: There may be symptoms in some cases. An important warning is passing out, or fainting. Most episodes of passing out are not a cause for alarm. But people should get checked out if they pass out while exercising, or if they experience palpitations and feel close to passing out. In addition, those with a history of heart attack or heart failure need to know their ejection fraction—a number that reflects the percentage of blood that is pumped from the left ventricle with each heartbeat. A good, efficient heartbeat pumps out more than half the blood in that chamber. When the heart is enlarged or scarred, however, the ejection fraction can drop below 35 percent or less. These people are at higher risk of SCA, and may be candidates for an ICD. A patient ought to be able to ask a doctor, “Is my heart enlarged, and if so, is there a number that would suggest I should have a defibrillator implanted?”

Post: What type of test is used to determine the patient’s ejection fraction?

Dr. Page: The most common test used to determine the ejection fraction is the echocardiogram. As I mentioned earlier, this test is basically a two-dimensional movie. Geometric calculations of the chamber volume just before and after the left ventricle squeezes suggest how much blood is pumped from the heart. For example, if the volume was a hundred before it squeezes and 50 after it squeezes, that’s an ejection fraction of 50 percent, which is good. But if the volume was 100 squeezing down to 75, that’s an ejection fraction of 25 percent, which is bad, and adds risk for sudden cardiac arrest.

Post: What should people do to lower their risk of SCA?

Dr. Page: If you have a personal or family history of recurrent pass-out spells, see a doctor. But all of us (whether or not we have heart disease) should care of our hearts. Discuss your cardiovascular risk factors with your doctor. Then, stop smoking, eat properly, exercise, control diabetes, and keep blood pressure and cholesterol in check to protect your heart and blood vessels.

Minimizing the risk of developing heart disease lowers the risk of heart damage and sudden cardiac arrest. Every day, I tell patients they ought to exercise. I don’t want to be a hypocrite, so I work out between 4:30 and 5:30 each morning, and then go to the office. I wish I ate a perfect diet, but I am trying!

Click here for more on SCA and an animation of the life-threatening emergency from The Heart Rhythm Society.

Watch for more from Dr. Page about saving lives with automated external defibrillators (AEDs) in a future Medical Update posting.

Preventing Sudden Cardiac Arrest The Saturday Evening Post

Here are 5 facts from the ongoing HRS Apples and Oranges campaign to help you understand the difference between the two heart emergencies—and why it matters:

1. SCA is a malfunction of the heart’s “wiring” or electrical system that controls your heartbeat. Heart attacks result from bad “plumbing”, or problems within the blood vessels that carry oxygen to the heart muscle.

2. SCA immediately and completely halts blood flow throughout the body, starving the entire body of oxygen. Heart attacks (also called myocardial infarctions or MIs) reduce or block circulation to a particular area of the heart muscle.

3. SCA occurs without warning and is often the first indication of unsuspected heart rhythm problems. Loss of consciousness occurs within 20 seconds. Heart attacks are usually (but not always) preceded by chest discomfort or trouble breathing and happen to people with high cholesterol, high blood pressure, or a personal or family history of heart disease. Heart attacks can trigger the deadly heart rhythm called ventricular fibrillation that causes SCA.

4. SCA has a cure. It is to “shock” the heart back to normal rhythm with a machine called a defibrillator. But the window of opportunity is short—chances of survival decrease about 10 percent for each minute spent waiting for a defibrillator. Fortunately, many therapies exist for heart attacks and getting prompt emergency treatment can avoid or reduce heart muscle damage when symptoms are recognized early.

5. SCA occurs almost 1,200 times per day in the U.S. Heart attacks claim the lives of about 600 Americans daily, including 300 who die before reaching the hospital. Most of those deaths are from SCA.

Click here for more on SCA from The Heart Rhythm Society.

Watch for more about preventing SCA and saving lives in future weeks.

Understanding Sudden Cardiac Arrest The Saturday Evening Post

A: Unlike warfarin, a blood thinner used for decades that is regulated by blood tests, the experimental drug dabigatran prevents blood clots with a fixed dose that is taken twice daily. The FDA approval of dabigatran, the first of a new class of drugs called direct thrombin inhibitors, is expected sometime this year.

Q: A doctors says our neighbor died in his sleep of a massive heart attack. Could a defibrillator have saved him?

A: While it is possible your neighbor did have a heart attack, the event that likely killed him was an abnormal heart rhythm called ventricular fibrillation. You do not give your neighbor’s age, but assuming he/she was an adult, a heart attack could have triggered the VF. The usual heart rate at rest is around 70 beats/min. During VF, the ventricular rate surges to 400-600/min, preventing effective contraction of the major pumping chambers that deliver unoxygenated blood to the lungs (right ventricle) and oxygenated blood to the rest of the body (left ventricle). The ventricles during VF look like a bag of squiggly worms, a belly dancer gone berserk. With no blood flow to the brain, loss of consciousness occurs in 10 to 20 seconds and death in five to eight minutes. Sudden cardiac arrest occurs almost 1,000 times per day in the U.S., claiming the lives of half of those who have heart attacks before they reach the hospital. It is likely that prompt use of a defibrillator to shock the heart rhythm back to normal could have saved his life.

Questions (and Answers) About Blood Thinners and Defibrillators The Saturday Evening Post

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Anti-tobacco forces wage war against the powerful tobacco lobby and the rising pandemic of cardiovascular and other smoking-related diseases in the world.

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Dick Cheney is protected by one, as are thousands of other Americans. Implantable cardioverter defibrillators reduce the risk of having sudden cardiac death to almost zero.

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Adult stem cells may represent the future of regenerative medicine—minus the controversy.

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Findings on hormone replacement therapy bring clarity to a longstanding debate, but for the millions of women on hormone therapy, questions remain.

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Robotic procedures are revolutionizing surgery and rapidly becoming the gold standard for minimally invasive surgery.

Top Medical News Stories of the 2000s The Saturday Evening Post

Months later, a doctor called to find out if Frank was still alive. He is, and he does not have brain damage. The doctor said the first shock was given 2½ minutes after Frank’s heart stopped and that the paramedics arrived in 5½ minutes. There are no words to express our appreciation to the people who helped a perfect stranger. Even a customs supervisor came over to help. I hope everyone who was so kind to us will read this letter, especially the two young ladies!

Virginia

California

We hope they do, too! Your letter is a good reminder that sudden cardiac arrest can happen anywhere and anytime. We’ve been advocating for years that automated external defibrillators (AEDs) should be as common as fire extinguishers. Fortunately, the lifesaving devices are now in visible locations at airports, stadiums, and some schools and churches. But most heart emergencies happen in the home. As the adage goes: Plan for the worst and hope for the best. When determining your response to a heart emergency at home, consider: Are you or a family member trained in CPR? Where is the nearest AED? How long will it take for the AED to arrive? Is it feasible to have a home defibrillator or one in a neighborhood clubhouse or lockbox? Today’s AEDs are so simple that almost anyone can use them without prior training. If you are in a position to help save a life by using an AED, remember three things: 1) recognize a heart emergency; 2) open the AED box; and 3) follow the prompts.

Husband’s Life Saved by Defibrillator The Saturday Evening Post