Your hospital just installed a new multidetector CT (MDCT) scanner of 64 slices or more, and your emergency-department physicians are clamoring for a 24/7 coronary CT angiography (CCTA) service; now what?
According to David Dowe, MD, a private-practice radiologist with Atlantic Medical Imaging, Atlantic City, New Jersey, and a passionate teacher and advocate of the study, a practice interested in launching a CCTA service must focus on three things: image quality/diagnostic superiority, service, and marketing.
On May 3, Dowe (who describes the study as beautiful, quick, and easy to administer) told radiologists at the annual American Roentgen Ray Society meeting in San Diego, California, that CCTA’s time has come, and not just in the emergency department.
Dowe asserts that the literature is replete with comparisons of CCTA with catheterization and stress tests in asymptomatic and symptomatic patients. Universally, he says, that work shows not only that CCTA is superior to stress testing as a first-line test, but also that it saves money, no matter where it is used.
“Why should half of US catheterizations show 50% or less stenosis?” Dowe asks. “There should never be another elective, negative diagnostic catheterization here. We have CCTA available in all 50 states.”
Image quality is a function of proper patient selection and preparation (and excellent equipment), Dowe says. The minimum equipment required is 64-detector MDCT system with prospective gating capabilities. Many courses are available covering the correct CT-imaging variables.
Proper patient selection: There are few patients for whom Dowe will not do CCTA. His list of absolute contraindications consists of five circumstances: uncontrolled atrial fibrillation, bigeminy, trigeminy, or high-grade heart block; severe, uncontrolled asthma; renal insufficiency; a prior allergic reaction to contrast while on steroids; and patient weight exceeding the 500-pound limit of his CT table.
There are some patients for whom CCTA will fail, Dowe says, but educating your schedulers on proper patient selection can minimize those events and save time. “Don’t be your own worst enemy; educate your schedulers,” he advises.
Patient preparation: Dowe advocates getting the preparatory packet to the patient in advance. The packet includes all of the necessary cardiac/medical-history forms, a brief description of what to expect during CCTA, and a beta-blocker.
In the interest of delivering excellent service, Dowe has two ways to administer the beta-blocker. In the first method, a day in advance, at one of Atlantic Medical Imaging’s sites, the patient’s resting heart rate is checked to make sure that it is above 60 beats per minute (bpm); if it’s lower, a beta-blocker is not needed (and could be harmful, Dowe says).
The alternative is to ask the patient to arrive an hour early for the exam (an option recommended for patients already on beta-blockers). The drug is then given only if necessary. Dowe never faxes a prescription to a patient, nor does he ask the ordering physician to take care of it. “Those are not friendly possibilities,” he says.
Before the exam, patients’ vital signs are obtained in a quiet room, and if their heart rates are greater than 72 bpm during breath holding, they are remedicated. Dowe uses oral beta-blockers exclusively, eliminating the need for preinjection/postinjection monitoring by a nurse and reducing the drug’s postexam effects. IV access is obtained, in another room, before the exam, and no one gets on the CT table without prior verification that his or her heart rate is where it needs to be.
Dowe describes the exam itself as very brief, taking 10 minutes or less. He shows patients their images before they leave the building (a key service element in his practice). He acknowledges that this is where the radiologist interested in launching a CCTA service could run into trouble. “Your partners may not support that activity; they may say, ‘What are you doing? We don’t bill for that visit.’” Dowe suggests that early in the endeavor, when processing takes extra time, patients should come back later in the day.
Whether immediate or postponed, that patient contact is not optional, Dowe notes. “You are not going to be involved in CCTA if you are as invisible as you are in a routine CT. There are too many other people who want to do this exam for you,” he says. After the patient leaves, the interpretation