• Posted March 30, 2023

How Round Is Your Heart? It Might Matter for Health

Assessing heart roundness may be a new way to diagnose cardiovascular conditions, new research suggests.

While doctors now use measures like heart chamber size and systolic function to diagnose and monitor cardiomyopathy and other related heart issues, cardiac sphericity (how round the heart is) may be another good tool.

"Roundness of the heart isn't necessarily the problem per se -- it's a marker of the problem,"said co-corresponding study author Dr. Shoa Clarke, a preventive cardiologist and an instructor at Stanford University School of Medicine in California.

"People with rounder hearts may have underlying cardiomyopathy or underlying dysfunction with the molecular and cellular functions of the heart muscle. It could be reasonable to ask whether there is any utility in incorporating measurements of sphericity into clinical decision-making,"Clarke suggested.

The researchers chose to focus on heart sphericity because clinical experience had suggested it might be associated with heart problems.

While past research had primarily focused on sphericity after the onset of heart disease, the research team hypothesized that sphericity might increase before the onset of clinical heart disease.

"We have established traditional ways of evaluating the heart, which have been important for how we diagnose and treat heart disease,"Clarke said. "Now, with the ability to use deep-learning techniques to look at medical images at scale, we have the opportunity to identify new ways of evaluating the heart that maybe we haven't considered much in the past."

For the study, Clarke's team used data from a subset of 38,000 UK Biobank study participants who had MRIs that were considered normal at the time of the scans.

Subsequent medical records from the volunteers showed which of the participants later went on to develop diseases like cardiomyopathy (such as enlarged heart), atrial fibrillation (irregular heartbeat) or heart failure, and which did not.

Using deep-learning techniques, the researchers automated the measurement of sphericity, finding that increased sphericity appeared to be linked to future heart troubles.

The findings were published March 29 in the journal Med.

"They say a picture is worth a thousand words, and we show that this is very true for medical imaging,"said co-corresponding author Dr. David Ouyang, a cardiologist and researcher at the Smidt Heart Institute of Cedars-Sinai, in Los Angeles.

"There's a lot more information available than what physicians are currently using. And just as we've previously known that a bigger heart isn't always better, we're learning that a rounder heart is also not better,"Ouyang said in a journal news release.

The study also included a look at the genetic drivers for cardiac sphericity, and they found overlap with the genetic drivers for cardiomyopathy.

"There are two ways that these findings could add value,"Ouyang noted. "First, they might allow physicians to gain greater clinical intuition on how patients are likely to do at a very rapid glance. In the broader picture, this research suggests there are probably many useful measurements that clinicians still don't understand or haven't discovered. We hope to identify other ways to use imaging to help us predict what will happen next."

More research is needed before the findings from this study can be translated to clinical practice, the authors stated.

The research team is sharing all the data from this study so other investigators can begin studying heart roundness as a risk factor for heart disease.

More information

The U.S. National Library of Medicine has more on heart disease.

SOURCE: Med, news release, March 29, 2023