A novel comprehensive radiation shielding system eliminates need for personal lead aprons in the catheterization laboratory.

OBJECTIVES: This clinical study evaluated the efficacy of a novel radiation shielding system for the cardiac catheterization laboratory designed to provide comprehensive protection that obviates the need for personal lead aprons. BACKGROUND: Invasive Cardiologists are exposed to occupational health hazards related directly to radiation exposure (RE) and indirectly to the orthopedic burden of wearing only partially protective lead aprons. Innovations to reduce these risks are warranted. A novel comprehensive shielding system (ProtegoTM , Image Diagnostics Inc, Fitchburg, Ma) has been validated in pre-clinical studies to provide excellent radiation protection, sufficient for the State of Michigan to certify it for use without need for personal lead aprons. METHODS: This clinical analysis measured RE to a single Physician operator utilizing the ProtegoTM shield (and not wearing personal lead apron) during routine cardiac catheterization procedures (diagnostic and interventional). RE was measured at both thyroid and waist level with a real-time dosimetry system (RaysafeTM , Billdal, Sweden), calculated on a median per case basis (mrems). Additional parameters collected included procedure type, access site, per case fluoroscopy time, and patient factors including body mass index. RESULTS: In n=98 cases (25% diagnostic, 75% interventional including 22% chronic total occlusions), median/case RE was 0.4 mrems (thyroid) and 0.2 mrems (waist). RE=0 in 12 cases. In no case did radiation exposure exceed 3.2 mrems. CONCLUSION: The ProtegoTM shield system provides excellent RE protection to the Physician operator, without the need for personal lead aprons and has the potential to reduce catheterization laboratory occupational health hazards.

A Novel Catheterization Laboratory Radiation Shielding System: Results of Pre-Clinical Testing.

BACKGROUND: This pre-clinical study evaluated the efficacy of a novel shielding system to reduce scatter radiation in the cardiac catheterization laboratory. METHODS: Using a scatter radiation phantom in a standard cardiac catheterization laboratory, a radiation physicist recorded radiation measurements at 20 reference points on the operator side of the table. Measurements were made with fluoroscopy and cine with the C-arm in the posterior-anterior (PA) and 40 degrees left anterior oblique (LAO) orientations. Scatter radiation doses were compared with and without use of the shielding system. RESULTS: Use of the shielding system was associated with >94.2% reduction in scatter radiation across all reference points in the PA and LAO projections with fluoroscopy and cine. With the shielding system, dose reductions at the location of the primary operator ranged from 97.8% to 99.8%. At locations of maximum scatter radiation, use of the shielding system resulted in dose reductions ranging from 97.8% to 99.8% with fluoroscopy and from 97.9% to 99.8% with cine. CONCLUSIONS: In this pre-clinical study, a novel radiation shielding system was observed to dramatically reduce scatter radiation doses. Based on these results, clinical testing is warranted to determine whether the shielding system will enable operators and staff to perform interventional procedures with less radiation exposure that may obviate the need to wear standard lead apparel. INDEXING WORDS: Radiation safety; occupational health; occupational hazard.

In-hospital outcomes of patients with chronic kidney disease undergoing percutaneous coronary intervention for chronic total occlusion: a systematic review and meta-analysis.

BACKGROUND: The relative safety and efficacy of percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) in patients with chronic kidney disease (CKD) have not been well defined. We performed a systematic review and meta-analysis of observational studies to assess in-hospital outcomes in this population. METHODS: We searched MEDLINE, EMBASE, and Cochrane Library databases from inception to April 2020 for all clinical trials and observational studies. Five observational studies with a total of 6769 patients met our inclusion criteria. Patients were divided into two groups based on estimated glomerular filtration rate (eGFR <60 ml/min/1.73m2 in CKD group and ≥ 60 ml/min/1.73m2 in non-CKD group). The primary outcome was in-hospital mortality. Secondary outcomes were acute kidney injury, coronary injury (perforation, dissection or tamponade), stroke and procedural success. Mantel-Haenszel random-effects model was used to calculate the odds ratio (OR) and 95% confidence intervals (CI). RESULTS: In-hospital mortality was significantly higher among patients with CKD undergoing PCI for CTO (OR: 5.16, 95% CI: 2.60-10.26, P < 0.00001). Acute kidney injury (OR: 2.54, 95% CI: 1.89-3.40, P < 0.00001) and major bleeding (OR: 2.58, 95% CI: 1.20-5.54, P < 0.01) were also more common in the CKD group. No significant difference was observed in the occurrence of stroke (OR: 2.36, 95% CI: 0.74-7.54, P < 0.15) or coronary injury (OR: 1.38, 95% CI: 0.98-1.93, P < 0.06) between the two groups. Non-CKD patients had a higher likelihood of procedural success compared to CKD patients (OR: 0.66, 95% CI: 0.57-0.77, P < 0.00001). CONCLUSION: Patients with CKD undergoing PCI for CTO have a significantly higher risk of in-hospital mortality, acute kidney injury and major bleeding when compared to non-CKD patients. They also have a lower procedural success rate.

Optimizing the Technique for Invasive Fractional Flow Reserve to Assess Lesion-Specific Ischemia.

BACKGROUND: Invasive fractional flow reserve (FFRINV) is the standard technique for assessing myocardial ischemia. Pressure distortions and measurement location may influence FFRINV interpretation. We report a technique for performing invasive fractional flow reserve (FFRINV) by minimizing pressure distortions and identifying the proper location to measure FFRINV. METHODS: FFRINV recordings were obtained prospectively during manual hyperemic pullback in 100 normal and diseased coronary arteries with single stenosis, using 4 measurements from the terminal vessel, distal-to-the-lesion, proximal vessel, and guiding catheter. FFRINV profiles were developed by plotting FFRINV values (y-axis) and site of measurement (x-axis), stratified by stenosis severity. FFRINV≤0.8 was considered positive for lesion-specific ischemia. RESULTS: Erroneous FFRINV values were observed in 10% of vessels because of aortic pressure distortion and in 21% because of distal pressure drift; these were corrected by disengagement of the guiding catheter and re-equalization of distal pressure/aortic pressure, respectively. There were significant declines in FFRINV from the proximal to the terminal vessel in normal and stenotic coronary arteries (P<0.001). The rate of positive FFRINV was 41% when measured from the terminal vessel and 20% when measured distal-to-the-lesion (P<0.001); 41.5% of positive terminal measurements were reclassified to negative when measured distal-to-the-lesion. Measuring FFRINV 20 to 30 mm distal-to-the-lesion (rather than from the terminal vessel) can reduce errors in measurement and optimize the assessment of lesion-specific ischemia. CONCLUSIONS: Meticulous technique (disengagement of the guiding catheter, FFRINV pullback) is required to avoid erroneous FFRINV, which occur in 31% of vessels. Even with optimal technique, FFRINV values are influenced by stenosis severity and the site of pressure measurement. FFRINV values from the terminal vessel may overestimate lesion-specific ischemia, leading to unnecessary revascularization.