Dowe, David A. MD* †
The current workup of the chest pain patient or asymptomatic patient with risk factors is based on indirect evidence. The Framingham score, laboratory analysis including a lipid profile, low density lipoprotein fractionation by particle size, stress tests, coronary artery calcium score, coronary catheterization and most recently such tests as carotid intima-media thickness all fail to look at the end organ that causes coronary artery disease (CAD) that being the wall of the coronary artery. This leads to a significant diagnostic inaccuracy. Inappropriate hospital admissions for chest pain or “rule out myocardial infarction” result in unnecessary hospital expenses of $5B annually in the United States.1 Missed myocardial infarctions with inappropriate discharge from the emergency department occurs in 2.1% to 4.0% of all acute myocardial infarctions.2,3 Concurrent with this problem is that many patients have undiagnosed moderate to severe CAD with myocardial ischemia and are completely unaware of this based on the aforementioned indirect workup of CAD (Fig. 1). In fact, recent work indicates plaque burden documented by coronary CT angiography (CCTA) correlates poorly with some well-known risk factors4 and little over 50% of patients confirmed to have moderate to severe plaque burden are prescribed statin therapy. It is highly likely in the next few years that we will see a seismic movement away from establishing the diagnosis of CAD by indirect evidence to that of establishing the diagnosis by looking directly at the wall of the coronary arteries using CCTA.
The thrust of this paper is to examine the key elements shared by successful CCTA clinics; impeccable image quality with a high examination success rate, service to the patient, referring physician and the community, and effective marketing. It is then that we will examine how these key elements differ depending on whether you are hospital or private office based and whether you are a radiologist or nonradiologist.
The foundation of any good business is to have a quality product, which is reliable and has significant meaning to the customer. In the radiology world this translates into image quality.
CCTA is a very rigorous examination. It requires diligence and thoroughness in patient selection, patient preparation, scan protocols with customized selection of pitch, milliamperage (mA), circulation time, and electrocardiogram-gated dose modulation while simultaneously being aware of the patient's radiation exposure. The radiation exposure from CCTA has been much ballyhooed when in fact the exposure from CCTA is equal to and usually considerably less than a SPECT Sestamibi stress test and far less than that of SPECT Thallium stress tests.5 If you limit your patient selection to patients who you can answer this question positively, “If CCTA did not exist would this patient be getting a SPECT stress test?,” and keep your radiation dose down to <13 mSv then you are in fact doing the patient a great service. You are giving this patient an examination that has a high sensitivity to plaques in the proximal vessels,6 the same plaques that are most frequently the cause of sudden death and large disabling infarcts, but also giving them an examination that has superior sensitivity to a 50% stenosis when compared with catheterization than any stress test. Having said that, CCTA has a high negative predictive value with both 16 and 64-slice technology nearly eliminating the possibility of CAD when studies are normal and performed adequately.
I strongly advocate that the physician be present at the CT console when the examination is being performed. By doing this, the physician has the opportunity to assess the patient's heart rate and possibly initiate additional β-blocker therapy. He may assist the technologist in selecting the appropriate pitch for that heart rate. He may select the appropriate mA for the patient's body habitus and first hand witness the calculation of the patient's circulation time. This obsession with detail before image acquisition directly translates into improved image quality. In our centers, we have a >99% examination success rate in all patients with success being defined as a study that is diagnostic for all 15 AHA segments of the coronary arterial circulation. Once image quality is achieved at this level the time spent postprocessing these images on the workstation decreases exponentially.
Image quality directly translates to diagnostic accuracy. Reliable diagnostic accuracy translates into more confidence on behalf of the referring healthcare provider resulting in more referrals. Our cardiology community has been slow to embrace CCTA; however, we receive 91% of our referrals from primary care providers, surgeons, anesthesiologists, etc, and we have considerable volume. I do not believe that any physician specialty “controls the patient” because if this were true then I would not be seeing the volume of cases that I see. With the exception that our practice was on the ground floor having started CCTA in December 2001 on an 8-slice scanner and we have considerable experience there is nothing else unique about our practice, our patient population, and our referrers to suggest that our success cannot be replicated elsewhere. In fact, we have trained over 1000 radiologists in CCTA who have gone on to establish successful practices elsewhere across the world.
The public frequently gets confused when confronted with details of CT technology. They have a vague understanding that “64 is better than 16” but their depth of understanding stops there. Topics the public understands are radiation exposure and service.
Because of our fastidious obsession with scan parameter selection and subsequent image quality, we end up spending more time at the CT console during the scan than we do at the workstation doing postprocessing. This allows us to do something that both referring physicians and patients greatly appreciate, that is, giving the patient the results of the study before they leave our facility. It takes approximately 30 to 50 cases for a radiologist to get up to speed so that they can do this in a timely fashion with no decrease in diagnostic accuracy. One could alternatively invite the patient back at a more convenient time to see their images if they are uncomfortable processing this quickly.
There is nothing else in medicine that a patient gets the results on the same day. They greatly appreciate this and recognize CCTA as being special not only because of its superior diagnostic capabilities when compared with stress tests but also for this level of service. The net effect is that patients see their coronary arteries on the workstation. This is a powerful experience for them. Nothing motivates a patient to do something about CAD than seeing their own CAD. We have 2 sayings in our facility, “Coronary CTA saves lives every single day” and “Coronary CTA alters statin management every single hour.”
Surprisingly to me, referring providers have encouraged me to insert myself like this into the patient's education. In return, they get a patient who understands CAD better, a patient who wants to do something about their level of CAD, and a patient who requires less of their time to convince them to initiate/maximize medical management or to a lesser extent obtain further diagnostic studies. Final reports are issued on the same day of the examination with significant findings requiring more diagnostic studies or intervention called in to the referrer immediately.
Key questions to ask yourself are “where are my referrals going to come from?” and “what are the most effective ways of me interacting with the sources of my referrals?”
Potential sources of referrals obviously include, first and foremost, cardiologists. CCTA has incited a turf war like no other between radiologists and cardiologists because of its potential to in many, many instances replace stress tests and elective, diagnostic coronary catheterizations. Referrals from cardiologists as reported to me from all over the United States is patchy proving the hypothesis that “all politics are local.” Large cardiology groups are likely to eventually purchase their own CT scanners. However, the recently announced cuts in reimbursement included in the Deficit Reduction Act and also future threats to reimbursement by private payers have made the profitability of owning a 64-slice CT questionable if you only do CCTA/CTA with it. Self-referral is increasingly being recognized as a huge problem with some states and private insurers beginning to legislate policies to thwart its effect on exploding healthcare costs. The self-referral political football continues to fly back and forth and it remains to be seen whether anything concretely will be done although the economic impact of self-referral is obvious.
In short, some cardiologists will refer to radiologists with open arms, others will refer in select instances and others will refer a patient to a radiologist for CCTA under no circumstances.
A more reliable and permanent referral pattern can easily be established with general practitioners, internists, nurse practitioners, physician assistants, surgeons, and anesthesiologists seeking preoperative clearance and cardiothoracic surgeons.
The most important aspect of marketing your CCTA Clinic is visibility. I highly recommend that radiologists review the CCTA images with patients as soon after the examination that it is reasonably possible to do so. Patients appreciate the diagnostic superiority of CCTA in and of itself and when combined outstanding service they are most happy. What this practice does is it forces patients to identify CCTA with the radiologist and the radiologists practice. This is marketing at its best. It is also wise to distribute images to the patients and their referring provider.
Advertising directly to the public is effective. CCTA has been approved by the public secondary to it being featured on the 3 separate national talk shows and being on the cover of 2 widely distributed magazines. The public and referring community now has a much better understanding of CCTA and what it can do for patient's lives than ever before.
The most prudent way of marketing to referrers is to do “lunch and lecture” seminars in the referrers office. A 30-minute PowerPoint presentation combined with a simple lunch is a great way to educate your community.
Speaking before civic groups, patient groups, benefit managers, and board of directors of large corporations are effective means of achieving a heightened awareness of CCTA and your practice on a local basis.
HOSPITAL VERSUS PRIVATE OFFICE SETTING AND RADIOLOGISTS VERSUS NONRADIOLOGISTS
The politics and economics surrounding CCTA are vastly different for the radiologists if they are hospital or private office based. In private offices radiologists almost always control equipment acquisition decisions, imaging protocol design, marketing decisions and they have a direct link to referring physicians. Therefore, the decision to enter the cardiac CT market is much easier than if they were hospital based. Key factors in making this choice are the economics of running a 64-slice scanner, supporting the radiologists learning CCTA when they are on a steep learning curve and hence take more time, encouraging the review of images with patients and reimbursement policies of your local Medicare carrier and private insurance plans.
These same key factors are operative in the hospital setting but they are dwarfed by the turf war between radiologists and cardiologists. This turf war exists despite the fact that the CCTA is poorly reimbursed. This is secondary to the well-recognized, huge impact that CCTA is having on diagnosing patients with suspected CAD. Whether we are talking about sensitivity, specificity, positive and negative predictive values for detecting a 50% stenosis compared with cardiac cath or detecting proximal soft plaque compared with intravascular ultrasound CCTA outperforms stress tests by a wide margin. In a nation where 91% of cardiac caths are on an elective basis, one could easily make a case that CCTA should precede every elective, diagnostic cath in an effort to prevent the 40% normal diagnostic only caths.
Secondary to its potential to replace stress tests and elective diagnostic caths cardiologists appropriately recognize that what has traditionally been their monopoly, the diagnosis of CAD, may now be shared with other imaging specialties namely radiologists. Cardiologists have been quick to use their considerable economic clout with hospital administrators to gain “reading privileges” for CCTA within the confines of the hospital. Usually radiologists are then hired to over read the noncardiac portions of the examination. This practice, in and of itself, has very little economic impact on the radiologists who up to now have not seen these patients who are usually imaged in the cardiologist's office or department. The legalities of these arrangements can be tricky and radiologists may want to consider getting legal representation to guide them through this process. The real danger is the expansion of these reading privileges to other specialties for other diagnostic examinations. Whether this translates into a real threat remains to be seen. Radiologists must be quick to limit CCTA reading privileges to patients referred by the jointly reading cardiologists group. Radiologists must retain the right to build their CCTA practice by marketing directly to the community and referring primary care healthcare providers, nurse practitioners, etc. It is here that radiologists stand to make a large gain as relationships and referral patterns already exist. These healthcare providers embrace sending CCTA patients to the radiologists not just because of the referral patterns, but they appreciate the superior image quality resulting in better diagnostic accuracy, the service and also the inability of radiologists to “steal the patient.” Most chest pain is gastrointestinal in origin. Primary healthcare providers want to be able to quickly “rule in” or “rule out” CAD so that they have the option of sending the patient to the specialist that patient could most benefit from.
The other area where radiologists are likely to gain “turf” is in imaging the acute chest pain patient out of the emergency room after hours. This turf is almost never encroached upon by nonradiologists for obvious reasons. This may work in favor of the radiologists. If a radiologist is capable of performing CCTA in the wee hours of the morning surely they are capable of doing it during the day. Radiology however must overcome the considerable staffing barriers in making a CCTA available on a 24/7/365 basis. This will not be easy as it also involves training CT technologists and 3-dimensional workstation technologists in the art of CCTA.
CCTA is revolutionizing the diagnosis of CAD. It has the potential to replace stress tests and diagnostic caths as the primary imaging study used to diagnose patients with symptoms and/or risk factors for CAD. Its most powerful use is excluding CAD secondary to its 99% negative predictive value. The potential to initiate such change is a major threat to people who have investments in terms of time, energy, and money in the technology it will likely replace. This resettling of turf is proving challenging across the country as hospital medical staffs come to terms with the disruption caused by this replacement technology.
To date, nobody has come to terms with the workforce and workflow issues surrounding the use of CCTA in the emergency room. The leverage that comes with providing CCTA after hours may help radiologists in gaining turf during daylight hours. Nonetheless, radiologists will likely do quite well in the field of cardiac CT because of entrenched referral patterns, appreciation of the service issues in outpatient imaging, the lack of threat they pose to primary care providers and their proven dedication to image quality.
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