LOS ANGELES — High-risk findings on myocardial perfusion studies require an immediate telephone call from a nuclear cardiologist to the referring physician, even when the temptation is to perform more tests to clarify the extent of cardiac viability, said Robert C. Hendel, M.D., at a meeting sponsored by the American College of Cardiology.
Dr. Hendel presented the case of a 31-year-old man, 6' 4” tall, 244 pounds, who presented with exertional chest pain. He had a history of radiation therapy for Hodgkin's disease.
During cardiac function tests, the patient was only able to proceed 4.5 minutes on the Bruce protocol before he experienced chest pain with ST-segment changes lasting about 15 minutes.
The patient's nuclear single-photon emission computed tomography (SPECT) images showed significant ischemia and large regions of decreased perfusion. Yet, in the interaction session attended by nuclear cardiologists, just over half of audience members voted that they would respond by immediately calling the referring physician.
Other attendees split their votes among other options, including repeating the SPECT using pharmacologic stress, performing additional imaging to assess viability, or reporting the likelihood of single-vessel disease.
Clearly, those in attendance were influenced by the patient's young age and the fact that more studies might provide more precise information.
However, the study's findings, combined with the patient's response to the cardiac function test, should be enough to warrant an immediate consultation with the referring physician, said Dr. Hendel at the meeting, which was cosponsored by the American Society of Nuclear Cardiology and Cedars-Sinai Medical Center.
“This is a very high-risk study,” he said. “Our responsibility is to pick up the phone and communicate that kind of information.”
In the case he presented, consultation with the referring cardiologist led to a referral to coronary angiography. The patient was found to have extensive coronary artery disease, including high-grade narrows (greater than 95%) in the proximal left anterior descending coronary artery involving the bifurcation of a large first diagonal branch.
“This high-risk anatomy was unsuitable for percutaneous coronary intervention, and he was referred for bypass surgery,” said Dr. Hendel following the meeting.
One week after his SPECT study, the patient underwent five-vessel bypass graft surgery. “He is doing well now, without symptoms.”
Dr. Hendel, a former president of the American Society of Nuclear Cardiology who practices with Midwest Heart Specialists in Fox River Grove, Ill., said nuclear cardiologists should lower their threshold for immediately conveying ominous test results to referring physicians.