Cardiologists at the Cleveland Clinic reduced radiation doses by 22 percent for diagnostic catheterizations and by 32 percent for PCI by leveraging new imaging technology, according to results published online Aug. 5 in Circulation: Cardiovascular Interventions.
Shikhar Agarwal, MD, MPH, and colleagues from the clinic’s Heart and Vascular Institute conducted a retrospective before-after assessment of an initiative to reduce radiation dose to patients and physicians in the catheterization laboratory. They noted that new digital imaging technology and flat-bed panel detector systems provide mechanisms to reduce radiation dose in the cath lab but operators may not know how to optimize them.
“Despite their widespread availability, their use is likely low because of lack of awareness among the interventional community,” they wrote. “One of these radiation reduction measures includes the low-dose acquisition technology that reduces the amount of x-ray delivered per frame, without appreciable loss of diagnostic quality.”
Their cardiac cath lab introduced a dose reduction initiative on Jan. 1, 2013, that called for a reduction of the default fluoroscopic frame rate from 10 to 7.5 frames per second. The program also emphasized the use of low-dose acquisitions, best radiation practices and monthly review of radiation dosimetry of each interventional cardiology fellow by the cath lab director.
To assess the impact of the initiative, Agarwal et al extracted data on patients who underwent diagnostic catheterizations or PCI between Jan. 1, 2012, and July 31, 2013. They compared all patients from 2013 and to matched controls from 2012 (2,838 diagnostic catheterizations and 209 PCIs in each group).
The analysis included five sites, four with Siemens Artis Zee ceiling-mounted systems and one with a Siemens Artis Zee Zeego multiaxis system.
Median total air kerma during diagnostic catheterizations in 2013 was 625 mGy vs. 798 mGy in 2012 and median total air kerma during PCIs was 1,675 mGy vs. 2,463 mGy, respectively. They determined that the new protocol reduced fluoroscopy-based and acquisition-based total air kerma significantly compared to their prior practice.
“[O]ur study clearly demonstrates that the use of lower fluoroscopic frame rate and low-dose acquisition can lead to marked reduction in total air kerma, even for projections involving steep angulation,” they wrote.