Surviving a Heart Attack in a Public Place

Cardiac arrests that can be treated by electric stimulation, also known as shockable arrests, were found at a higher frequency in public settings than in the home, according to a recent study.

The study compared home and public cardiac arrests under various scenarios. For example, the study considered whether bystanders or emergency medical services (EMS) personnel witnessed the cardiac arrest, and whether the person experiencing the arrest received treatment with an automatic external defibrillator (AED). [Read more…]

Body Cooling Treatment Studied for Pediatric Cardiac Arrest

Blanketrol mattress and blanket used for body cooling.

The National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health, has launched the first large-scale, multicenter study to investigate the effectiveness of body cooling treatment in infants and children who have had cardiac arrest. The Therapeutic Hypothermia after Pediatric Cardiac Arrest (THAPCA) trials total more than $21 million over six years.

Therapeutic hypothermia, or body cooling, has been successfully used in adults after cardiac arrest and in newborn infants after birth asphyxia, or lack of oxygen, to improve survival and outcomes, but it has not been studied in infants or children who have had cardiac arrest.

“Children who have experienced cardiac arrest can suffer long-term neurological damage or death,” said NHLBI Acting Director Susan B. Shurin, M.D., a board-certified pediatrician. “There are abundant data demonstrating the benefits of hypothermia in adults with cardiac arrest, but very limited experience in children. This study begins to assess the effectiveness of therapeutic hypothermia in children, and should lead to evidence-based guidelines that will optimize both quality and rates of survival.”

During body cooling treatment, THAPCA participants lie on mattresses and are covered with blankets. Machines circulate water through the blankets and mattresses to control the participants’ body temperatures. Researchers do not yet know how body cooling will affect participants, since many factors can contribute to brain injury after cardiac arrest. However, they believe body cooling could provide several benefits, including less inflammation and cell death.

According to a 2008 review of pediatric cardiopulmonary resuscitation in the journal Pediatrics, about 16,000 children suffer cardiac arrest each year in the United States. Their hearts stop pumping effectively, and blood stops flowing to their brains and other vital organs. In many cases, the outcome is death or long-term disability.

Cardiac arrest in infants and children has many causes, such as strangulation, drowning, or trauma. It can also be a complication of many medical conditions.

“Our goal is to minimize brain injury in infants and children who experience cardiac arrest and ultimately improve survival rates,” said co-principal investigator J. Michael Dean, M.D., M.B.A., professor of pediatrics and chief of the Division of Pediatric Critical Care Medicine at the University of Utah School of Medicine, Salt Lake City.

The THAPCA centers enroll participants in one of two randomized, controlled clinical trials. One evaluates participants who suffered cardiac arrest outside the hospital, while the other evaluates participants who suffered cardiac arrest in the hospital. Within each trial, there are two active treatment groups: therapeutic hypothermia (cooling the patient to 89.6-93.2 Fahrenheit) and therapeutic normothermia (maintaining the patient at 96.8-99.5 Fahrenheit). Both trials are trying to reduce fever, which commonly occurs after cardiac arrest and can lead to more severe outcomes.

“These trials are addressing the question: What is the optimal temperature for an infant or child after cardiac arrest?” said co-principal investigator Frank W. Moler, M.D., M.S., a professor in the Department of Pediatrics and Communicable Diseases at the University of Michigan, Ann Arbor. He added that in previous studies exploring therapeutic hypothermia, the comparison or control groups did not receive therapeutic normothermia to prevent fever.
Woman lying on a Blanketrol mattress and blanket used for therapeutic hypothermia.
Blanketrol mattress and blanket used for therapeutic hypothermia.

Participants in the THAPCA trials must be older than 48 hours and younger than 18 years and must be enrolled in the study within six hours of suffering cardiac arrest. Once a parent or guardian provides consent, the participant is randomly assigned to one of the two treatment groups. The therapeutic hypothermia group in each trial receives the hypothermia treatment for two days and then normothermia treatment for three days, which ensures that the body temperature is kept within a normal temperature range. The patients in the therapeutic normothermia groups receive normothermia treatment for all five days.

After the five-day period, the clinical care team will continue to provide study participants with optimal medical care. Participants will undergo neurological and behavioral testing a year after the cardiac arrest.

The THAPCA trials involve 34 clinical centers in the United States and Canada. The C.S. Mott Children’s Hospital at the University of Michigan serves as the lead clinical center, while the data coordinating center is based at the University of Utah School of Medicine.

Source: NIH, October 19, 2010

Study Shows Obesity Is a Major Risk for Heart Failure

The results of the Multiethnic Study of Atherosclerosis (MESA) identifies "the biological effects of obesity on the heart" as a serious reason for 72 million overweight Americans to worry about their health.

Senior study investigator Joao Lima, M.D., says "Even if obese people feel otherwise healthy, there are measurable and early chemical signs of damage to their heart, beyond the well-known implications for diabetes and high blood pressure. Now there is even more reason for them to lose weight, increase their physical activity and improve their eating habits."

The development of heart failure of some 7,000 mean and women, aged 45 to 84 was followed by researchers conducting the MESA study, which started in 2000. To date, of the 79 participants who developed congestive heart failure 44% were obese with a body mass index (BMI) of 30 or more. They were also found to have higher blood levels of interleukin 6, C-reactive protein and fibrinogen, key immune system proteins involved in inflammation, than non-obese adults. An 84% greater risk of developing heart failure was accounted for by a near doubling of average interleukin 6 levels.

The links between inflammation and the combination of risk factors known as the metabolic syndrome alarmed the researchers from 5 U.S. universities.

The researchers from five universities across the United States also found alarming links between inflammation and the dangerous mix of heart disease risk factors known as the metabolic syndrome. Its combined risk factors for heart disease and diabetes—high blood pressure, elevated blood glucose levels, excess abdominal fat and abnormal cholesterol levels, and particularly obesity—double a person’s chances of developing heart failure.

"More practically, physicians need to monitor their obese patients for early signs of inflammation in the heart and to use this information in determining how aggressively to treat the condition," says Lima, a professor of medicine and radiology at the Johns Hopkins University School of Medicine and its Heart Institute. "Our results showed that when the effects of other known disease risk factors—including race, age, sex, diabetes, high blood pressure, smoking, family history and blood cholesterol levels—were statistically removed from the analysis, inflammatory chemicals in the blood of obese participants stood out as key predictors of who got heart failure," says Lima.

The study found that higher levels of interleukin 6 and a tripling of average levels of C-reactive protein in study subjects increased the possibility of heart failure by 36%.

What this tells us is that both obesity and the inflammatory markers are closely tied to each other and to heart failure," says lead researcher Hossein Bahrami, M.D., M.P.H. Bahrami, a senior cardiology research fellow at Hopkins, says "the basic evidence is building the case that inflammation may be the chemical route by which obesity targets the heart, and that inflammation may play an important role in the increased risk of heart failure in obese people, especially those with the metabolic syndrome."

Each year, nearly 300,000 Americans die from heart failure.

Source: Journal of the American College of Cardiology, May 6, 2008

Can Daily Aspirin for Heart Attack Prevention be Dangerous?

Nearly 250,000 Americans may suffer from bleeding complications each year because they take an adult-sized aspirin daily to prevent heart attack, rather than baby aspirin. That is the conclusion of University of Kentucky heart disease researchers following a study that found that the commonly-prescribed 325 mg adult tablet may be more than many people need each day.

Published in the Journal of the American Medical Association, the study showed that doses higher than a baby aspirin (75 to 81 mg) are associated with increased risk of gastrointestinal bleeding and are no more effective at preventing cardiovascular events long-term.

Gill Heart Institute cardiologists and University of Kentucky College of Medicine faculty Dr. Charles Campbell, Dr. Steven R. Steinhubl and Dr. Susan Smyth, along with Dr. Gilles Montalescot of the Instjtut de Cardiologie-Centre Hospitalier Universitaire Pitié-Salpêtrière in Paris, France, systematically reviewed published data regarding clinical studies involving aspirin dosing. Even in patients with diabetes, who may be more difficult to treat, they found no large-scale studies that support higher doses of aspirin.

"While aspirin is an effective drug for the prevention of clots," said Campbell, lead author of the report, "the downside of aspirin therapy is an increased tendency for bleeding (particulary from the GI tract). We believe the minimum effective dose should be utilized (75-81 mg)." However, Campbell notes, "We also believe more study in this area is warranted to determine if the minimum dose is effective for everyone, or if dose should be adjusted from person to person."

Thirty-six percent of the adult population in the U.S. take 10 to 20 billion aspirin tablets annually to prevent clots, the main cause fo heart attacks and strokes.

"Patients should check with their doctor to be sure, but there is almost no one who needs to take more than 81 mg of aspirin a day for protection from heart attacks," Campbell said. Meanwhile, physicians face the challenge of identifying the best blood-thinning regimen for their patients.

Source: University of Kentucky

Speedy Hospitalization After Heart Attack Onset Greatly Improves Care

A Mayo Clinic Research study finds that getting a heart attack patient to hospital within one to two hours of heart attack onset can assure that chances of receiving proper treatment are 70 percent better than a patient who waits 11 to 12 hours. The results of the study were presented at the American Heart Association’s Scientific Sessions 2007, In Orlando, Florida.

"This research should emphasize to patients that getting help immediately, by calling 911, gives them the best chance of receiving treatments we know can help save their lives or lessen the damage to their hearts" says Henry Ting, M.D., lead Mayo Clinic cardiovascular researcher on the national study. "If patients wait at home for hors with symptoms and come in later, unfortunately they aren’t getting the proper treatment."

The most serious type of heart attack is known as a STEMI, for which the best treatment is reperfusion therapy. The study documents how long it took for 440,398 heart attack patients to arrive at the hospital after heart attack onset, and correlate arrival time with the rates of reperfusion therapy they received upon arriving at the hospital.

  • Of patients who arrived at the hospital within one to two hours of heart attack onset, 77% received reperfusion therapy
  • Of those patients arriving at the hospital within two to three hours of attack onset, 73% received reperfusion therapy
  • Of those patients who reached the hospital within 11 to 12 hours of attack onset, only 46% received reperfusion therapy

"Although current guidelines recommend that STEMI patients who reach the hospital within 12 hours after their symptoms started should receive reperfusion therapy, we found that this is not happening," Dr. Ting says. "These delays represent a novel and modifiable risk factor and warrant further investigation. These results show that gaps remain in quality of care in patients with STEMI — first, we need to encourage patients with potential heart attacks to come to the hospital as early as possible; second, hospitals need to implement systems that treat all eligible patients rapidly regardless of the delay in presentation."

Source: Mayo Clinic

Most Heart Attack Patients Stop Taking Lifesaving Medications Within Three Years

Surprisingly, many heart attack victims stop taking their lifesaving medication within three years of the attack. This was the finding of a Mayo Clinic study presented November 5 at the American Heart Association’s Scientific Sessions 2007.

By following patients at 6, 12 and 36 months after an attack, it was found that smokers were more likely to discontinue taking their prescribed medications within three years. Longer term, patients who were enrolled in cardiac rehabilitation programs tended to continue their medications longer than those who were not enrolled.

The researchers recommended a two-program plan for improving the public’s heart health: first, direct education at heart attack patient who are smokers, encouraging them to adopt physicians’ aftercare advice about continuing medications education; and second, encourage all heart patients to participate in a cardiac rehabilitation program, possibly increasing their likelihood of continuing prescribed treatments.

"The study clearly documented that treatments exist that improve outcomes following heart attacks, but patients need to comply with the treatment regimens for the goal of improved patient health to be realized," says Nilay Shah, Ph.D., the study’s lead researcher.

Patients discontinue taking medications too soon for a variety of reasons, including cost, says Veronique Roger, M.D., M.P.H., co-author of the study. More research is crucial to understand and resolve the barriers patients face as they recover from heart attacks she says.

The Mayo researchers evaluated 292 patients enrolled at the Olmsted County, Minnesota registry of heart attack patients, together with their medication histories up to 10 years. These patients had been discharged from the hospital and were taking ACE inhibitors, beta-blockers and statins to help prevent another heart attack.

Results showed that:

  • At six months, smokers were significantly less likely to continue all three heart medications compared to nonsmokers.
  • At six months, 92 percent of the patients taking statins continued treatment, and by three years only 44 percent of the patients continued taking statins.
  • Similarly, the rate of beta-blocker continuation dropped from 89 percent at six months to 47 percent at three years.
  • The rate of ACE inhibitor continuation dropped from 77 percent at six months to 37 percent at three years

Other members of the Mayo research team are: Henry Ting, M.D., Victor Montori, M.D., and Amy Wagie. Their work was supported by the Mayo Foundation for Medical Education and Research.

What Triggers Heart Attacks and Stroke?

Strokes, heart attacks, and cardiac arrest are usually the result of cholesterol-rich plaque deposits in the arteries going to the brain and heart.
They occur, when a particular activity triggers them.

Stressful physical exertion, anger, waking up from sleep, and certain infections are some of the triggers that top the list.
While most heart patients perform each of the above activities at one point or another, knowing the triggers can help you take measures to prevent them or control their intensity when they occur.