What if the absence of coronary artery disease could be confirmed quickly and reliably without cardiac catheterization?
For years, the perceived need for a cardiac cath, or coronary angiography, has helped shape how many donation after circulatory death (DCD) hearts are offered for transplant. But according to Brian Lima, MD, transplant surgeon and a national leader in DCD heart recovery, that assumption deserves a hard reset.
It’s an approach Dr. Lima believes could reduce delays, increase DCD heart offers and, as Vanderbilt’s own experiences have shown, deliver outcomes comparable to cardiac cath without introducing new patient safety concerns.
A Problem Hidden in Plain Sight
As with most meaningful process changes, this one started with noticing a trend.
“You can only accept the donor hearts you’re offered,” Dr. Lima noted during the webinar. “And a lot of donor hearts aren’t even being offered.”
National data supports that concern. A study published in the Journal of Heart and Lung Transplantation shows that while the number of DCD donors has increased – and donor age has risen – the rate of DCD heart recovery has not kept pace. In fact, a snapshot from 2023 shows non-recovery outpacing transplantation, even among donors with characteristics comparable to those whose hearts were successfully transplanted.
“I can’t help but wonder, as I’m sure many of you do, if one of the main barriers driving this is the lack of access to a cardiac cath,” says Dr. Lima.
For OPOs, this challenge may feel familiar. The primary purpose of a cardiac cath is to rule out coronary artery disease, but during donor management, obtaining an invasive cath can be ethically and logistically difficult. Not all U.S. hospitals have the equipment or the individuals to perform or read this test, particularly on nights or weekends.
“There’s no telling how many potential heart donors don’t even make it to being offered, just for the presumption that, well, they’re going to want a cath,” says Dr. Lima.
A Turning Point at Vanderbilt
For the team at Vanderbilt, the shift toward a CT-first mindset began with a single donor case at their hospital.
During DCD evaluation, clinicians noticed a white speck of calcium on a routine, non-contrast chest CT. That finding prompted further testing, including the first case of a coronary angiography performed intraoperatively during normothermic regional perfusion (NRP).
The heart was ultimately transplanted. While that made the intraoperative cath a success, the team recognized this approach wasn’t feasible for most donor hospitals, and it led to a larger realization.
If the presence of calcium could trigger further vetting, perhaps the absence of calcium could help teams move forward with confidence in organ offers.
What a Non-Contrast Chest CT Already Tells Us
Most potential donors already undergo a non-contrast chest CT as part of a donor management evaluation. From that single scan, clinicians can assess coronary artery calcium (CAC), a well-established marker that reliably identifies coronary calcification and correlates with total plaque burden.
Importantly for OPO workflows, CAC assessment:
- Does not require gated imaging
- Does not require contrast
- Can be derived from standard chest CTs performed at any hospital
Calcium is typically categorized visually as none, mild, moderate or severe, and that distinction matters.
“If there’s no calcium,” says Dr. Lima, “there are very few centers, Vanderbilt included, that would turn down that heart, even in the presence of other risk factors.”
In other words, a calcium-free, non-contrast chest CT result may be sufficient to move forward with a heart offer, without creating a bottleneck by waiting on a cath.
“Or if there is a little bit of calcium,” continues Dr. Lima, “We should test a little bit further and still potentially in a non-invasive way.”
An Approach Already Used in Other High-Risk Settings
Outside organ recovery, CT-based coronary assessments have already been adopted.
- Post-transplant, CT angiography is increasingly used to monitor for cardiac allograft vasculopathy (CAV), replacing cardiac caths in many cases.
- In transcatheter aortic valve replacement (TAVR) programs, CT is the first-line screening tool for coronary assessment, even in elderly, high-risk patients. The largest study of its kind, published in the Journal of American College of Cardiology (JACC), showed a negative predictive value of 97% for a clean coronary CT.
As Dr. Lima notes, “It’s something to keep in mind that our go-to initial screening tool for this population at high risk for having concomitant coronary disease is not an invasive cardiac cath but CT angiography.”
Five Years of Data and Key Findings
To better understand whether CT-based vetting holds up in donor management, the team at Vanderbilt analyzed more than 500 donor heart transplants over five years, comparing outcomes between donors evaluated with cardiac caths and those evaluated with CT alone.
Key findings included:
- Early graft function was similar between groups
- 30-day and one-year mortality were comparable
- Outcomes remained consistent after adjusting for donor type, including the higher proportion of DCD donors in the CT group
- Even among donors 40 years and older, there was no obvious mortality penalty associated with CT-based coronary vetting
Subgroup Analysis: Donors ≥40 Years Old
Within the CT cohort, outcomes were also similar between donors evaluated with non-contrast CT and those who received contrast-enhanced CT.
Dr. Lima believes a key takeaway is that a CT-first approach could be easily incorporated into the current donor assessment workflow. “At the end of the day, the vast majority of donors already get a CT,” says Dr. Lima. “A lot of the data we need to vet coronaries is already being acquired; we just haven’t been using it to its full potential.”
What Implementation Actually Requires
Dr. Lima says scaling this approach comes down to a few practical considerations:
- Rapid DICOM ingestion from any donor hospital
- Standardized reconstruction of images to enable visual CAC grading
- Secure, real-time remote access for transplant surgeons and cardiologists
- Ideally, AI-assisted coronary calcium scoring to support fast, consistent interpretation, especially overnight
With these elements in place, CT-based donor heart vetting becomes not just feasible but also routine.
Potential for Transformation
Dr. Lima closed with a message for the field:
- Not being able to perform a cardiac cath does not make a donor heart unofferable
- Chest CT is safe, scalable and already being done for most potential donors
- A non-contrast chest CT is an excellent universal minimum screen
- CT-based vetting performs similarly to invasive cath for early and one-year outcomes
While long-term surveillance, particularly around CAV, remains an important area for continued study, the near-term opportunity is clear.
“I think it would really be transformative for the field and obviously have massive impact for patients on our waitlist that we’re all caring for,” says Dr. Lima.
For OPOs looking to transplant more DCD hearts, this is a change that could start tomorrow.
Interested in Implementation?
As OPOs explore CT-first donor heart evaluation, access to timely coronary artery calcium scoring and cardiac CT interpretation is critical. CompuMed supports OPOs with secure DICOM sharing, centralized donor case data and expert remote interpretations. Together, these capabilities help reduce delays and support faster, more confident decision-making.
Contact us to learn how CompuMed can support your CT-first donor evaluation workflow.
Continue the Conversation
Watch the follow-up webinar featuring Dr. Brian Lima and Lee Keddie, president and CEO of CompuMed, as they answer questions submitted by OPOs and transplant teams following the highly attended first webinar session.
