Cardiovascular disease in the 20th century served to drive an expanding market for medical devices, and a year-end 2001 report from the American Heart Association (AHA; Dallas, Texas) suggests the trend is unlikely to change in the current century.The AHA report says that somewhat more than 60 million Americans suffer from some form of heart disease, producing nearly 1 million fatalities each year. This results in 40% of deaths in the U.S., making it the nation's No. 1 killer.

Improved diet and consistent programs of exercise – as well as cessation of smoking – could reduce this toll by nearly one-third, according to the AHA report, but the organization notes that such advice generally is being ignored by Americans. These trends thus offer a continuing opportunity for those making devices and drugs to treat heart disease and related illnesses.

Broken out from the heart disease statistics, strokes killed 167,366 people in 1999, still leaving the total of heart disease deaths far ahead of the No. 2 killer – cancer, accounting for nearly 550,000 deaths in 1999. Computed by itself, stroke was No. 3 on the AHA list. Accidents claimed nearly 100,000 lives and Alzheimer's disease killed nearly 45,000 yearly.

The understanding that cardiovascular illness comes in several varieties is key to the cardiovascular sector, since it suggests not just one but a range of opportunities that need to be understood in terms of products, services and their funding opportunities. And certainly, just as important for the other medical device sectors, these opportunities are important in terms of related diseases and co-morbidities.

Overall, the AHA estimated the cost of treating heart disease in 2001 at just under $300 billion, with that figure expected to grow this year to nearly $330 billion. The organization put the direct costs of treating heart disease – such as through nursing home and home care services, physician and professional services, drugs, devices and other medical durables – at about two-thirds of the total costs. The remaining third of indirect costs results from mortality and lost productivity, according to the AHA.

While the association reported that the increased use of drugs to treat high blood pressure could save a great many lives, it also credited the emergence of new devices as having growing life-saving potential.

At the top of its list, it put drug-coated stents as offering new treatment opportunities, a developing technology which Cardiovascular Device Update has followed closely and will continue to report on. Another technology receiving mention by the AHA was the growing use of heart assist devices – known as left ventricular assist devices (LVADs) and progress in artificial heart technology (see following story on Abiomed's experience with its AbioCor replacement heart).

The diversity of opportunity in the cardiovascular sector perhaps can be understood best by looking at the classification system used by the AHA in its "2002 Heart and Stroke Statistical Update." As the study points out, the numbers reflecting the extent of cardiovascular disease are based on the International Classification of Diseases (ICD) system, currently in its 10th version, with periodic revisions of that system serving to change the specific numbers, sometimes dramatically.Very roughly, the ICD codes used by the AHA, and describing what it calls cardiovascular disease (CVD), serve to encompass nearly 62 million Americans suffering one or more forms of CVD, with these ICD-classified conditions coming in five types:

  • High blood pressure (50 million victims).
  • Coronary heart disease (12.6 million, including 7.5 million who have experienced myocardial infarction and 6.4 million with angina).
  • Stroke (4.6 million)
  • Congenital cardiovascular defects (1 million).
  • Congestive heart failure (4.79 million).

These figures, in turn, translate to 40% of all fatalities in the U.S. (including accidents) or about 1 million deaths annually, according to the AHA report.In these terms, the most serious and significant classification in the AHA's study is the instances of heart attack, defined as fatal coronary heart disease or myocardial infarction (MI).AHA estimates that in 2002, 1.1 million Americans will have "a new or recurrent coronary attack, with about 45% of these dying as a result." That 45% produces nearly 500,000 deaths each year, or about half of the total deaths annually as a result ofCVD. This statistic clearly makes heart attack the center of the coronary disease target, offering one of the largest opportunities for medical device manufacturers in terms of therapy, and for diagnostic firms, in terms of early assessment.

The primary therapy when MI occurs is defibrillation, with automated external defibrillation (AED) systems over the past two years becoming more and more available in casinos, passenger airlines and airports, as well as in many other high-stress, high-traffic areas.

The need for even greater availability was underlined by the association's citing a study of AED use at Chicago's O'Hare and Midway airports. In the 10 months following installation of AEDs at the two airports, "mounted a distance of one minute apart in plain view," nine of 14 victims of MI were defibrillated and survived with no brain damage. That figures to a 64% survival rate and compares to a 49% rate of survival in communities where defibrillation is available in five to seven minutes, and a survival rate of just 5% when MI victims are simply rushed to the hospital, according to the AHA. Overall, the AHA estimates that 40,000 people could be saved each year in the U.S. with the consistent use of CPR and if AEDs "were more widely available."

Such figures assume some availability of external defibrillation, but the majority of MI attacks happen unobserved, primarily at home, a fact that, in turn, calls for increased use of implanted defibrillators.Additionally, the AHA estimates that about 250,000 MI attacks occur each year without the victim being hospitalized, and more than half who die of coronary heart disease (more broadly defined than MI) have experienced no previous symptoms of the disease.

While more than half of those experiencing a heart attack survive, these survivors often live with greatly reduced health. About two-thirds of heart attack victims don't recover completely, and about 18% of men and 35% of women will have another heart attack. About 22% of men and 46% of women will be disabled because of heart failure, and 12% of victims under age 65 are unable to return to work.

Overall, cardiovascular disease is the primary cause of premature, permanent disability in the labor force, according to the AHA report, and CVD is becoming slowly but increasingly prevalent among younger age groups. As just one instance, the number of sudden cardiac deaths in those in the 15 to 34 age range rose from 2,719 in 1989 to 3,000 in 1996, with a 30% increase in such deaths among young women.

Some of the key findings from the report:

  • One American dies of CVD every 33 seconds, a total of more than 2,600 each day.
  • Of the nearly 1 million deaths from CVD each year, 150,000 of these fatalities occur to those under 65.
  • In 1999, more women than men died of CVD: 512,904 females, 445,871 males.
  • The rate of a first major cardiovascular event increases from seven per 1,000 for men from ages 35 to 44, to 68 per 1,000 at ages 85 to 94. Comparable rates for women come 10 years later in life.
  • Black and Mexican-American women have higher risk factors for CVD than white women of comparable socio-economic status, which "underscore[s] the critical need to improve screening, early detection and treatment of CVD-related conditions for black and Mexican-American women, as well as for women of lower SES in all ethnic groups," the report said.