Safer, faster, more effective: Why cardiac PET should be the primary nuclear modality

The image quality is better with PET and it can offer additional information on microvascular blood flow to diagnose ischemia with non-obstructive coronary arteries (INOCA). It also can produce more accurate myocardial perfusion images in patients whose body habitus or anatomy can make conventional imaging more challenging. This includes patients with obesity, women with larger breasts and people with certain lung or thoracic anatomical characteristics.

Identifying hidden causes of non-obstructive chest pain

One of the most significant advantages of cardiac PET is its ability to measure myocardial blood flow reserve (MFR), providing a noninvasive assessment of coronary microvascular dysfunction. This condition affects the capillaries supplying the heart and can cause chest pain and myocardial ischemia even when the major coronary arteries appear normal on an angiogram.

Snyder said patients, particularly women and some African American patients, have historically been told that their chest pain was not cardiac-related when conventional angiography failed to identify obstructive coronary artery disease.

“Now we know, you might have normal arteries, the arteries that you can see on an angiogram, but it's those microvascular arteries where there is some disease,” he said.

Until recently, evaluating this dysfunction often required invasive testing to assess coronary blood flow in response vast dilators. Cardiac PET can provide this physiological information noninvasively, potentially helping physicians identify the cause of persistent symptoms and select appropriate treatment.

The additional information may also help cardiologists determine which patients do not need invasive coronary angiography, avoiding the risks and costs associated with catheter-based procedures when they are unlikely to provide additional clinical value.

ASNC guidelines and investment decisions

The Cardiac PET Alliance's advocacy comes as the nuclear cardiology community encourages laboratories to modernize their imaging capabilities.

Snyder pointed to recent guidance from the American Society of Nuclear Cardiology (ASNC), which he said explicitly favors vasodilator PET over vasodilator SPECT when selecting between the two modalities for clinical assessment. ASNC also issued a statement that PET is now deemed the best cardiac nuclear imaging modality in an effort to get commercial payers to stop trying to call the use of the modality "experimental" and contesting billing for it.

For healthcare organizations considering new capital investments, he argued that the combination of lower radiation exposure, shorter examination times and additional physiological information makes PET a compelling choice.

PET should complement other noninvasive cardiovascular imaging technologies, including coronary CT angiography and cardiac MRI, Snyder emphasized. Each modality provides different information, and the appropriate examination depends on the patient's clinical circumstances. For example, PET may be particularly useful for patients with chronic kidney disease when iodinated contrast used for coronary CT angiography is a concern.

Expanding access and demonstrating value of PET

Despite its clinical advantages, wider adoption of cardiac PET faces financial and operational barriers, including equipment costs, reimbursement and the resources required to establish imaging services. The alliance wants healthcare systems and payers to evaluate PET's value across the entire continuum of cardiovascular care, rather than focusing exclusively on the initial cost of an imaging examination.

By helping physicians make more confident diagnoses and potentially avoiding unnecessary invasive procedures, Snyder believes PET can lower downstream costs while improving safety.

“We want to really educate them is it actually has an opportunity for cost savings overall,” he said.

The alliance's goal is to increase the availability of cardiac PET across communities, giving more patients access to a noninvasive test that can evaluate both coronary perfusion and microvascular physiology.

For Snyder, the case for wider adoption comes down to combining the more accurate diagnosis with a better patient experience and the potential to reduce the need for invasive testing. He said expanding access to these capabilities is an important step toward safer, more cost-effective cardiovascular care.