During the decade of the 1990s, basic science advances, technologic developments and economic drivers comprised the primary external dynamics affecting the practice of cardiovascular medicine and surgery. The principal expression of these developments was to contain costs and to reorganize the process of cardiovascular care. At the turn of the new century, concerns regarding the appropriateness of care, how best to reduce variability in health care outcomes and how to evaluate quality of care are emerging as important issues to be addressed.
Over the next 5-10 years, basic science and technologic developments will continue to be determinants of what does and does not happen in medical care in general and specialty care (such as cardiac services) in particular. Of real concern is how the demographics of the "baby boomers" will affect health care. These demographic issues will play out not only in terms of the cost of care and access to care in individual markets around the country, but also in terms
of their effect
on the Medicare Trust Fund and Social Security as the basic social contracts between the growing population of elderly and the federal government.
The goals of health care will expand to include increased consideration of work status capability, the ability to live independently and, as an expression of these forces interacting, the inclusion of quality-adjusted life years as an outcome measure. Given that the expression of cardiovascular disease is an age dependent variable, even if molecular biologic and genetic factors are defined for cardiovascular diseases, it will still be at least one or two generations before we will be able to appreciate true cures or prevention as the desired therapeutic endpoint.
Federal legislative initiatives of the '80s and '90s, most significantly Medicare prospective payments for hospitals (diagnosis-related groups, or DRGs), physician payment reform and the rise of commercial managed care have all increased competitive pressures on hospitals and practitioners. Caught between increased technical capabilities and constrained health care budgets, medical and surgical competition in cardiac care has intensified. In many circumstances, these pressures have expressed themselves in consolidation throughout the healthcare industry. These and other organizational changes affect how patients relate to their caregivers and how specialists relate to their referrals, to each other and to their practice organizations (offices, clinics, foundations and hospitals). These forces are having an important effect on clinical decision-making.
A significant development in this new and evolving environment for cardiac care has been the increasing isolation of invasive cardiology from the other specialties involved in treating coronary artery disease (CAD). This isolation is organizational, clinical and spatial (for example: the practice of invasive cardiology apart from comprehensive cardiovascular care programs and centers; the demise of daily, multi-specialty clinical conferences on CAD patients to discuss treatment alternatives; the increase in "self referral" for "ad hoc" angioplasty after coronary angiography; etc.). As several of our respondents put it, care decisions can benefit from having "two or three pairs of eyes" involved in assessing diagnostic images, since variability in interpretation of an angiogram (currently the most popular diagnostic tool for CAD) has a significant effect on diagnostic and treatment decisions. The isolation of cardiology might be the most important organizational development in cardiovascular care over the last decade because of its effect on clinical pathways for CAD patients - for example, on which patients are referred for cardiac surgery. Whether or not it continues will have a significant effect on how clinical and technologic advances actually affect care in the future.
Significant Demographic Points
- Coronary artery disease is the leading cause of death for both men and women in the United States.15 Although the focus of this report, and of most therapies for CAD, is hospital-based procedures, almost half of the people who die from CAD each year do so without ever being diagnosed or treated in a hospital.15
- The percentage of all US deaths related to CAD has declined by about 25% in the last ten years.19, 15 This may be attributable to improvements in CAD management, including primary care physician case management and/or interventional developments.27
- Over half of the hospital-based procedures for treating CAD as well as over half of the deaths related to CAD are in persons aged 65 and older.15 This trend is likely to continue and become more significant as baby boomers age, increasing the size and proportion of the population over 65. The first cohort of baby boomers will turn 65 in the year 2011.15
Utilization of Diagnostic and Therapeutic Procedures
According to the most recent national statistics through 1997 from the American Heart Association, the volume nationwide of cardiac catheterization, coronary artery bypass graft (CABG) surgery, and percutaneous transluminal coronary angioplasty (PTCA) all increased substantially over a two-decade period. Cardiac catheterizations increased 299 percent from 1979 to 1997. CABG increased 432 percent from 1979 to 1997. PTCA increased 188 percent from 1987-1997.15
In New Jersey and the adjoining states of New York and Pennsylvania, population-based rates of procedures from 1995 through 1998 (using 1999 population estimates) show the following (see table below):
- Population-based rates of selected catheter-based diagnostic procedures increased by 22% in New Jersey, faster than in New York (20% increase over the same period, but lower use rates across the board) and Pennsylvania (10% increase over the same period).
- Population-based rates of PTCA increased 19% in New Jersey, 33% in New York, and 11% in Pennsylvania. Pennsylvania's PTCA use rates are significantly higher than those in the other two states.
- Over the same period, the population-based rate of stenting increased almost twelve-fold in New Jersey. In New York the rate increased between three- and four-fold (beginning from a higher base in 1995 but resulting in a lower rate than New Jersey by 1998). Pennsylvania's rate increased fourteen-fold and was by 1998 significantly higher than New Jersey's.
- CABG rates were up 13% in New Jersey, down less than 1% in New York and up less than 1% in Pennsylvania, where the population-based rate of CABG surgery exceeds those in New Jersey and New York by approximately 60%.
Selected Cardiac Procedures Per 100,000 1999 Population In Three States
Source: New Jersey Department of Health & Senior Services
|Coronary Arteriography - 2 Caths
|Left Heart Cath
|Angio Card-Left Heart Structure
|Total Selected Procedures
These are ubiquitous procedures that constitute an important component of both the volume and revenues of hospital-based care across the United States. Because of the sheer numbers of patients and providers involved in these procedures, the most difficult problem to solve but one that is crucial to addressing the quality and appropriateness issues for treatment of CAD is how to reduce variability in both the process of care and in outcomes of treatment.
Compliance with Guidelines and Clinical Pathways
There is a growing body of evidence that physicians do not follow generally-accepted treatment guidelines for CAD. For example, Jencks et al. examined the use nationally of eight care processes from national guidelines for the treatment of acute myocardial infarction (among them aspirin use, administration of beta blocker, speed of intervention with angioplasty or thrombolytic therapy for heart attack). In all but one of these indicators New Jersey performed worse than the median state.20
Organizational approaches to addressing this practice issue focus on ensuring the necessary infrastructure for high-quality clinical programs: strong clinical and administrative leadership; adequate resources to assure the financial viability of the large, complex organizations that these clinical programs have become; and meeting the growing need for information management for clinical practice. Strategies include: organizing teams within hospitals around multi-disciplinary clinical lines (examples: acute chest pain; stroke; transplant), and regionalizing care in centers of excellence which can be physical or virtual centers, the latter built around common practice protocols, physician education and QI programs, and sophisticated communication and information technologies, as well as necessary patient transportation systems. The advent of new methods for diagnosing AMI, coupled with better pharmacologic therapies (anticoagulants, for example), make it possible to rule out AMI in the emergency room, avoiding "rule out AMI" admissions for many patients.
Definitions of Clinical Terms
Several clinical terms are repeated throughout this document; we present here brief definitions for the most frequently used.
Acute myocardial infarction (heart attack; MI) is a disorder in which damage to an area of heart muscle occurs because of an inadequate supply of oxygen to that area. Causes include clot formation or spasm in an artery that supplies blood to the heart muscle (a coronary artery).
Stable angina (chest pain) is triggered by exertion or stress and relieved by rest. Any event that increases oxygen demand can cause angina, including exercise, cold weather, emotional tension, and even large meals.
Unstable angina, often an intermediate stage between stable angina and a heart attack (angina has progressed in severity and frequency), can occur during rest or mild exertion.
Cardiac catheterization is the generic process of passing catheters from peripheral access sites through either veins or arteries to central locations in either the right or left sides of the heart.
Coronary angiography is a diagnostic tool that involves threading a catheter through a peripheral artery to the heart. Dye is injected into the catheter, which enables an X-ray image of the coronary arteries to be displayed on a monitor revealing the location and approximate size of any blockages.2 Additional information such as the pumping ability of the heart can also be obtained.15
Lipids are fats or fatlike substances. Lipid-lowering drugs are prescription medications that can lower your blood levels of cholesterol and another form of fat in the blood, triglycerides, to help prevent or reduce the plaque buildup in blood vessels that can lead to a heart attack or stroke.
Myocardial ischemia is a deficiency of oxygen-carrying blood in an area of heart tissue due to blockage of the coronary arteries. Myocardial ischemia can cause angina (see above), which is painful. However, ischemia can also be painless - known as silent ischemia. Without intervention, myocardial ischemia can lead to a heart attack.
Thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body. Sometimes, a piece of atherosclerotic plaque can act in the same manner as a blood clot. Thrombi or emboli can lodge in a blood vessel and block the flow of blood in that location.
Thrombolytics, or "clot-busting" drugs are used in the early medical treatment of heart attacks. These drugs dissolve the clot, or thrombus, responsible for causing artery blockage and heart-muscle tissue death. The earlier thrombolytic drugs are administered, the lower the mortality rate.
The two standard procedures most frequently referred to in this paper for treating coronary artery disease are coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA, or angioplasty).
CABG involves taking blood vessels from the patient's chest, stomach, or wrist and grafting them in front of and beyond the blocked arteries, so the blood flows through the new graft around the blockage. The operation can be very invasive, requiring opening the chest, routing blood through a heart-lung machine, stopping and then restarting the heart, and transplanting new vessels. Minimally invasive bypass surgery uses smaller incisions in opening the chest. In the "off-pump" version the surgeon works on the heart while it is still beating. If a heart-lung bypass machine ("pump") is used in minimally invasive bypass surgery, the heart is stopped while fiber-optic scopes and instruments are passed through a number of small incisions. The surgeon then works on the heart guided by a video image from a tiny camera inserted through an incision.
Angioplasty (or PTCA) uses radiographic techniques to guide a catheter directly to the blocked vessel. In balloon angioplasty, the surgeon passes a tiny deflated balloon through the catheter to the site of the vessel obstruction. The balloon is inflated to compress the plaque against the walls of the artery, flattening it out so that blood can once again flow through the blood vessel freely. Although most common in patients with 1-2 affected vessels, angioplasty can be used in patients with three-vessel disease. In one version of a procedure known as atherectomy, a tiny cutter spinning at 2,500 rpm removes plaque fragments from the arterial walls. "Ad hoc" angioplasty (also known as "look-see" or "on the fly" angioplasty) means that balloon angioplasty (and possibly stenting - see below) is performed immediately as follow-up to angiography. Primary angioplasty refers to performing PTCA on acute myocardial infarction (AMI, or heart attack) patients as quickly as possible to restore the flow of blood to the heart muscle.
Coronary stents are expandable mesh tubes deployed by angioplasty catheters at the sites of obstructions to maintain the free flow of blood through the vessel after angioplasty. The stent pushes against the wall of the artery to keep it open. Stent use is associated with lower rates of reocclusion than with standard angioplasty.
Clinical guidelines cited in this report were developed by the American College of Cardiology (ACC) and the American Heart Association (AHA).