CDU Executive Editor

This year's annual meeting of the American Heart Association (Dallas) featured a rather odd report, that report describing the successful slowing of a female patient's atrial fibrillation (AF) with a rather unusual technique.

The successful therapy that calmed her heart was a matter of saying to her the word "Mississippi."

Hoping to acquire some sort of "inside" slant on this report, Cardiovascular Device Update interviewed the researcher before he made his presentation. We asked him what he thought was the underlying and essential clinically important point of this report — since talking AF sufferers through a litany of the 50 states probably isn't likely ever to be used as "standard-of-care" for treating this problem.

He came up with what may seem to be rather obvious. He said the research demonstrated the mind's action in its ability to regulate the heart.

That observation does not seem to offer any great breakthrough epiphany. It's readily obvious that situations providing high stress can precipitate heart attack and stroke and that normal, everyday stress is probably an important factor in the development of hypertension. And one of the other presentations at the annual meeting was titled "Persistent anxiety predicts acute cardiac events in coronary heart disease patients."

More than arteries and pumps

But the longer we thought about this report, and the entire AHA annual meeting for 2007, the more we felt that it underlined an emerging emphasis — or one that should emerge — concerning cardiovascular disease. Over the past decade, and especially the past five years, the emphasis has been on the coronary arteries and the ability to clear them, or reclear them. More generally, the emphasis has been on the heart, the pump that keeps the whole thing going.

But a clogged artery or an irregularly beating pump are often only the presenting symptoms of much broader problems, because cardiovascular disease is essentially a systemic disorder. And while it's easy to comment on cardiovascular disease being systemic, it's quite another thing to really understand what that means — that several other areas of the body, from the bones to the brain, and a whole range of financial, cultural, even family, conditions participate in the often chaotic cascade of events that can lead to clogged arteries and pump irregularities.

This year's AHA meeting struck us as presenting the idea of cardiovascular illness as a complicated systemic process, more so than in previous years, because of the range of topics not dealing directly with the heart or coronary arteries, but with many other topics still under the umbrella of cardiovascular concern. (Or maybe it was there in previous years but CDU wasn't particularly aware of it in those years).

This broader emphasis could be seen in the meeting's range of topics, from obesity in its very earliest stages to the keystone topic of improved ways of delivering the newest techniques and technologies.

Early obesity at issue

The AHA used the conference to issue a Scientific Statement titled "Clinical Implications of Obesity With Specific Focus on Cardiovascular Disease," offering an in-depth analysis of the various ways obesity produces and increases cardiovascular risk factors. These include: the development of insulin resistance; increases in serum LDL-C and triglyceride concentrations; increased blood pressure and hypertension; declines in pulmonary function; an association with circulating inflammatory markers; dysfunctions in the autonomic nervous system; and an association with abnormalities in cardiovascular structure and function. All of these, according to the statement, can be reversed through weight loss.

The discussion of weight loss is also presented in systemic fashion, rather than via repetition of the familiar, eat-less-exercise-more mantra. It emphasizes the overall modification of behaviors and provides a systemic-style range of strategies for altering thinking and behavior (see table, next page).

Beyond this, the scientific sessions didn't simply beat the "you should lose weight" mantra, but provided research on the earliest signs of obesity.

One of these offered evidence concerning a method for identifying, at the earliest point in a person's life, those children who might be at risk, or greater risk, for adult obesity and the related cardiovascular problems. Thomas Kimball, MD, professor of pediatrics at the University of Cincinnati College of Medicine, said, "Obesity is a problem that develops early in childhood and has adverse cardiovascular consequences early in childhood." His presentation discussed the "body mass index [BMI] rebound age," the age at which BMI is lowest — somewhere between age 4 and age 7 — before increasing through later childhood, adolescence and adulthood.

The finding was that those children whose BMI rebound came shortly after age 4 had grater evidence of cardiovascular risk, using a variety of measures including echocardiograms, and greater likelihood to be obese, than if it came later. This BMI rebound age also tended to come earlier for girls than boys, with the investigators concluding that this put women at greater risk for obesity. Kimball said, "the crux of the matter is when these habits are set in childhood, they are difficult to break. It's not just the child's problem, but becomes a family issue."

PAD: threat keeps on growing

Another area in which the broader systemic emphasis of this conference appeared was in the increasing number of studies on peripheral artery disease (PAD), thus concerning those vessels farthest away from the heart and miniscule in size compared to the coronary arteries.

Andrew Sumner, MD, of Heart Station and Cardiac Prevention at Lehigh Valley Hospital (Allentown, Pennsylvania), reported on an increase in PAD, not in patients with obvious symptoms of the diseases but in those showing no symptoms. "We were interested in seeing if the prevalence of peripheral artery disease in the general U.S. population is increasing, specifically among people who don't have known coronary artery disease, said Sumner, lead author of the study.

Sumner and his team used ankle-brachial index measurement, which determines the ratio of blood pressure in the arms and legs, with a ratio of less than 0.9 indicating PAD. They found that the prevalence of PAD among asymptomatic adults 40 years old and older increased from 3.7% in a 1999-2000 survey to 4.6% in a 2003-2004 survey and that there was a parallel increase in obesity, diabetes, hypertension and smoking.

Still another of the "very earliest warning sign" types of studies was one on cardiovascular problems that can occur in the womb. Sadia Malik, MBBS, MPH, of the University of Arkansas Medical School (Little Rock, Arkansas) reported on the occurrence of hypoplastic left heart syndrome, or, more directly, a left side of the heart that is under-developed.

The study had found, according to Malik's report, that there was a heavy association between this lack of development and the mother's reporting having a urinary tract infection from one month before conception through the first trimester of pregnancy.

Bystanders offer a shocking experience

The other end of the spectrum for cardiovascular disease as a systemic problem is usually considered the development of the best technologies and the best therapies. But the actual end of that spectrum is the methods for delivering these systems and technologies — in other words, the access to and delivery of cardiovascular care, with those processes dependent upon what's going on in the broader social infrastructure to make these connections, and doing it either efficiently or quite slowly.

One of these areas is the delivery of shock therapy to the heart of a patient experiencing cardiac arrest, a heart attack of the electrical variety rather than of the plugged-up artery variety. This has been pursued in the area of automated external defibrillation (AED), with the attempt to place AEDs in as many places as possible and into as many hands as possible. But the technology probably comes with the halo effect of being rather mysterious and probably not everyone can use an AED properly in a stressful situation and so why put them where they are available to anybody.

One of the studies probably designed to demystify the technology, reported on data indicating that even "bystanders" — and therefore meaning a large of people happening at the scene of a heart attack untrained in AED use — can use theses devices effectively and that the lack of training was no large barrier to their use.

Myron Weisfeldt, MD, presented the research, acknowledging that there has been other research showing rapid use of the devices by various populations, but he emphasized that this study was unique in looking at real-life situations and the action of bystanders whose knowledge ranged from no medical training at all to, for a few, a good bit of training.

"This is not a randomized, controlled study, but it describes what is going on in the real world, where people at the scene of a cardiac arrest are saving lives," Weisfeldt said.

The results were drawn from 11 urban and rural communities participating in the Resuscitations Outcomes Consortium (ROC), a network of communities involved in studies of prehospital emergency care.

A total of 9,897 EMS-treated patients were included in the study, with bystanders administering CPR in 2,991 cases (30.4%) and using an AED with CPR in 249 cases (2.5%). Overall, 7% of the 9,867 patients survived to hospital discharge, with survival varying according to the type and timing resuscitation attempted.

Of patients who had bystander CPR but no use of an AED, just 8% survived to hospital discharge. When bystanders provided CPR and attached an AED and the device delivered a shock, survival increased to 33%, more than four times that of CPR alone.

Weisfeldt said the findings provide strong support for making AEDS even more widely available in communities than they are now. "When you compare [the cost of $2,000 for an AED] to the cost of other safety measures required by laws, such as seat belts in automobiles and sprinkler systems to help control fires in buildings, my own conclusion is that it's not an enormous expense," he said.

Therapeutic help needed in time

Another type of cardiovascular care delivery falls under the category of getting the heart patient to the best therapies in a hospital setting, with one researcher noting that we don't do a very good job of this. As evidence, he cited studies that a person is transported to the hospital three times faster after an auto accident than after a serious cardiovascular incident.

One study focused on methods for speeding the care of patients experiencing ST-Elevation Myocardial Infarction (STEMI), the most serious type of heart attack in which the blockage of blood to the heart results in damage to the heart muscle and potentially cardiac arrest. An estimated 500,000 STEMI events occur each year in the U.S., and if the person is treated in time, the arteries can be opened with balloon angioplasty or reperfusion procedures in the emergency room. On the other hand, STEMI patients who go into cardiac arrest before arriving at the emergency room are less likely to survive percutaneous coronary interventions.

"Christopher Granger, MD, professor of medicine and director of the cardiac care unit at Duke University Medical Center (Durham, North Carolina), said, "Even though 25 years of research shows that people having a heart attack are more likely to survive when their blocked arteries are opened quickly, national statistics on heart attack treatment tell us that these patients are still treated too slowly or not at all."

The study focused on a regional system of care to improve reperfusion rates, called Reperfusion of Acute MI in Carolina Emergency Departments (RACE), at 65 hospitals across five regions in North Carolina. Each of the regions had a full-time nurse coordinator to help carry out the RACE protocol, and the PCI centers established specific elements, such as a single telephone number to immediately activate the catheterization lab team, to improve the speed of reperfusion .

In non-PCI hospitals, for clot-busting therapy, the percentage of patients receiving treatment within 30 minutes improved from 35% to 52 %. For the 237 patients transferred from a non-PCI hospital to a PCI hospital, first door-to-balloon times improved from 160 minutes to 128 minutes, and to 106 minutes for hospital that routinely transferred for PCI. At the PCI hospitals, median door-to-balloon (DTB) times improved from 85 minutes, before the RACE protocol, to 74 minutes afterwards. And after the RACE program, 72% of patients received PCI within 90 minutes.

Get the cath lab going

Another study emphasized a method of achieving faster DBT by activating the cath lab at the earliest possible moment and getting ready to do balloon angioplasty before the STEMI patient even arrives at the hospital. Developed by a Minnesota hospital, the program asked paramedics to call a specially appointed coordinator to activate the cath lab procedures when the patient's symptoms demonstrated acute myocardial infarction.

Shorter DBT was achieved for patients presenting during normal workday hours (cath lab team being in-house) as well after hours (cath lab team not in-house). All heart attack patients with early cath lab activation had a DBT of less than 90 minutes, regardless of the time of day, and 75% of heart attack patients with early activation that presented during a normal workday hours had a DBT of less than 60 minutes.

Another report found that STEMI patients treated at medical facilities with on-site cath labs have significantly better one-year survival rates than those treated at outside facilities. And a review of more than 400,000 hospital STEMI admissions found that the longer it takes patient to reach a hospital after signs of first symptoms, the less their chances for receiving any reperfusion therapy upon admission.