Getting worse, not better
Previous studies have shown that women are less likely than men in acute coronary syndromes to receive the transradial approach and P2Y12 inhibitors, but none have specifically looked at intracoronary imaging, Dr. Mamas said.
To fill the gap, the researchers drew on data from 994,478 patients in the British Cardiovascular Intervention Society registry, of whom, 8.4% of 738,616 men and 7.9% of 255,862 women received intracoronary imaging.
Women in the imaging group were older, more likely to be an ethnic minority, and more likely to undergo PCI for non–ST-segment elevation MI than their male counterparts.
One of the more surprising findings was that rates of IVUS and OCT were superimposable between the sexes at the start of the study but quickly diverged starting in around 2012, when the technology took off, Dr. Mamas said. In the most recent data, use was about 3% lower in women overall and rising to 6% in those with stable angina.
“Whilst the disparities between men and women are significant, the bigger question is why are we using so little imaging in guideline-recommended cases where there is a benefit?” he said.
Possible actionable items, he suggested, include providing older physicians who didn’t have access to intracoronary imaging during their training with opportunities in their cath lab or with industry sponsors to increase their skills and confidence. Intracoronary imaging use could also be routinely captured in U.S. and European PCI registries and used as a quality metric.
“In left main, you see a massive difference between centers, and that’s the kind of data that drives discussion,” Dr. Mamas said. “If we start reporting quality metrics, such as radial use, intracoronary imaging, P2Y12 inhibitors by center, then you’ve got something to benchmark centers against.”
Nathaniel Smilowitz, MD, an interventional cardiologist at New York Langone Health, who was not associated with the study, said that it’s troubling to see that the utilization intravascular imaging is so low, despite randomized trials and large meta-analyses showing a mortality benefit associated with its use in PCI.
“Even among men, only 19.6% in the later years were getting intravascular imaging performed to guide their coronary intervention, so one out of five,” he said. “There are opportunities to improve.”
Dr. Smilowitz said he’s also perplexed as to why adoption would be lower in women but that the findings echo those in other domains where women receive less intensive cardiovascular therapy.
“There’s no biological, really plausible, mechanism as to why the need for intravascular imaging would be lower and, particularly, because they showed in stent thrombosis, for example, where intravascular imaging is tremendously important, there were still sex differences,” he said. “So even with clear indications for imaging, women just received the optimal therapy less often than men. It’s disappointing.”
Dr. Smilowitz agreed that there may be a need to incorporate intravascular imaging into metrics, which are reported back to physicians, potentially even for comparisons with peers or regional rates to incentivize physicians to improve uptake.
“As a society, we’ve been quite slow to integrate intravascular imaging to guide PCI and we can do better,” he said.
A version of this article first appeared on Medscape.com.