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ABSTRACT: Objectives: Identifying the distributions and determinants of fluoroscopy time for invasive coronary angiography (ICA) and percutaneous coronary intervention (PCI). Background: Invasive coronary angiography (ICA) and percutaneous coronary intervention (PCI) are significant contributors to radiation exposure from medical imaging in the US. Fluoroscopy time is a potentially-modifiable determinant of radiation exposure for these procedures, but has not been well characterized in contemporary practice. Methods: We evaluated the distribution of fluoroscopy time in patients undergoing ICA and/or PCI in the CathPCI Registry(®) , stratifying patients by numerous clinical scenarios. Hierarchical models were used to determine patient, procedure, operator and hospital-level factors associated with fluoroscopy time for these procedures. Results: Our study included a total of 3,295,348 ICA and PCI procedures performed by 9,600 operators from January 2005 through June 2009. There was wide variation in fluoroscopy times for these procedures with median [IQR] fluoroscopy times of 2.6 [1.7 - 4.5] minutes for ICA, 6.7 [4.2 - 10.8] minutes for ICA in patients with prior coronary artery bypass grafting (CABG), 10.1 [6.0 - 17.4] minutes for PCI, 10.7 [7.0 - 16.9] minutes for PCI with ICA, and 16.0 [10.6 - 24.0] minutes for PCI and ICA in patients with prior CABG. Prolonged fluoroscopy times (>30 minutes) were rare for ICA, but occurred in 6.7% of PCIs and 14.7% of PCIs in patients with prior CABG. After accounting for patient characteristics and procedure complexity, operator and hospital-level factors explained nearly 20% of the variation in fluoroscopy time. Conclusions: Fluoroscopy times vary widely during ICA and PCI with operator and hospital-level factors contributing substantially to these differences. A better understanding of potentially-modifiable sources of this variation will elucidate opportunities for enhancing the radiation safety of these procedures. © 2013 Wiley Periodicals, Inc.
Catheterization and Cardiovascular Interventions 05/2013; · 2.29 Impact Factor
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ABSTRACT: BACKGROUND: Today's imaging laboratories face challenges including reimbursement, prior authorization, and accreditation standards. The impact on the practice of nuclear cardiology in the United States is unknown. We conducted a survey of ASNC members to provide a snapshot of nuclear cardiology imaging laboratories in 2011. METHODS AND RESULTS: The survey identified practice patterns including personnel, volumes, protocols used, and laboratory characteristics. We employed random sampling methodology stratified geographically. The response rate was 19.5% (73/374 laboratories). A non-random survey conducted in 2001 of 25 laboratories served as a comparator. A total of 73 laboratories, representing 202 physicians and 177 technologists responded. The reported median procedural volume was 1,225 studies annually; 88.9% of laboratories were accredited. Compared with 2001, dual isotope imaging protocol use dropped from 72% to 15.6%. Five markers of quality were surveyed. Half of laboratories use the American College of Cardiology's Appropriate Use Criteria, 61% used segmental scoring, and 32% provided guidance on post-test therapeutic management. 89% perform catheterization correlations while only 33% implemented radiation dose tracking. CONCLUSIONS: This survey of ASNC members provides critical information on nuclear cardiology practice to better target and service our members' needs. These data can prove invaluable to target educational needs and inform healthcare policy of contemporary nuclear cardiology practice.
Journal of Nuclear Cardiology 09/2012; · 2.67 Impact Factor
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Andrew J Einstein,
Carl D Elliston,
Daniel W Groves,
Bin Cheng,
Steven D Wolff,
Gregory D N Pearson,
M Robert Peters,
Lynne L Johnson,
Sabahat Bokhari,
Gary W Johnson,
Ketan Bhatia,
Theodore Pozniakoff,
David J Brenner
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ABSTRACT: Coronary computed tomographic angiography (CCTA) is associated with high radiation dose to the female breasts. Bismuth breast shielding offers the potential to significantly reduce dose to the breasts and nearby organs, but the magnitude of this reduction and its impact on image quality and radiation dose have not been evaluated.
Radiation doses from CCTA to critical organs were determined using metal-oxide-semiconductor field-effect transistors positioned in a customized anthropomorphic whole-body dosimetry verification phantom. Image noise and signal were measured in regions of interest (ROIs) including the coronary arteries.
With bismuth shielding, breast radiation dose was reduced 46%-57% depending on breast size and scanning technique, with more moderate dose reduction to the heart, lungs, and esophagus. However, shielding significantly decreased image signal (by 14.6 HU) and contrast (by 28.4 HU), modestly but significantly increased image noise in ROIs in locations of coronary arteries, and decreased contrast-to-noise ratio by 20.9%.
While bismuth breast shielding can significantly decrease radiation dose to critical organs, it is associated with an increase in image noise, decrease in contrast-to-noise, and changes tissue attenuation characteristics in the location of the coronary arteries.
Journal of Nuclear Cardiology 11/2011; 19(1):100-8. · 2.67 Impact Factor
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ABSTRACT: The clinical course in pulmonary arterial hypertension (PAH) is variable, and there is limited information on the determinants and progression of right ventricular (RV) dysfunction. The objective is to develop PET metabolic imaging of the RV as a noninvasive tool in patients with PAH.
We performed PET scanning in 16 patients with idiopathic PAH (age, 41±14 years, 82% women) using (13)N-NH(3) for perfusion imaging and (18)F-fluorodeoxyglucose for metabolic imaging. The myocardium was divided into 6 regions of interest (3 left ventricular [LV], 3 RV), and time-activity curves were generated. A 2- compartment model was used to calculate myocardial blood flow (MBF), and Patlak analysis was used to calculate the rate of myocardial glucose uptake (MGU). All patients underwent cardiac catheterization, cardiac MRI, and cardiopulmonary exercise testing with gas exchange. MBF, MGU, and the ratio of RV/LV MGU were correlated to clinical parameters. Pulmonary artery (PA) pressure was 79±19/30±8 mm Hg (mean, 48±10 mm Hg). MBF was 0.84±0.33 mL/g per minute for the LV and 0.45±0.14 mL/g per minute for the RV. Mean MGU was 136±72 nmol/g per minute for the LV and 96±69 nmol/g per minute for the RV. The ratio of RV/LV MGU correlated significantly with PA systolic (r=0.75, P=0.0085) and mean (r=0.87, P=0.001) pressure and marginally with maximum oxygen consumption (r=-0.59, P=0.05). RV free wall MGU also correlated well with mean PA pressure (r=0.66, P=0.03).
PET scanning with (13)N-NH(3) and (18)F-fluorodeoxyglucose is a feasible modality for quantifying RV blood flow and metabolism in patients with idiopathic PAH.
Circulation Cardiovascular Imaging 09/2011; 4(6):641-7. · 5.94 Impact Factor
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ABSTRACT: The use of ionizing radiation in cardiovascular imaging has generated considerable discussion. Radiation should not be considered in isolation, but rather in the context of a careful examination of the benefits, risks, and costs of cardiovascular imaging. Such consideration requires an understanding of some fundamental aspects of the biology, physics, epidemiology, and terminology germane to radiation, as well as principles of radiological protection. This paper offers a concise, contemporary perspective on these areas by addressing pertinent questions relating to radiation and its application to cardiac imaging.
European Heart Journal 08/2011; 33(5):573-8. · 10.48 Impact Factor
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Andrew J Einstein
Journal of Nuclear Cardiology 08/2011; 18(4):561. · 2.67 Impact Factor
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ABSTRACT: To quantify the effect of reduced life expectancy on cancer risk by comparing estimated lifetime risks of lung cancer attributable to radiation from commonly used computed tomographic (CT) examinations in patients with and those without cancer or cardiac disease.
With the use of clinically determined life tables, reductions in radiation-attributable lung cancer risks were estimated for coronary CT angiographic examinations in patients with multivessel coronary artery disease who underwent coronary artery bypass graft (CABG) surgery and for surveillance CT examinations in patients treated for colon cancer. Statistical uncertainties were estimated for the risk ratios in patients who underwent CABG surgery and patients with colon cancer versus the general population.
Patients with decreased life expectancy had decreased radiation-associated cancer risks. For example, for a 70-year-old patient with colon cancer, the estimated reduction in lifetime radiation-associated lung cancer risk was approximately 92% for stage IV disease, versus 8% for stage 0 or I disease. For a patient who had been treated with CABG surgery, the estimated reduction in lifetime radiation-associated lung cancer risk was approximately 57% for a 55-year-old patient, versus 12% for a 75-year-old patient.
The importance of radiation exposure in determining optimal imaging usage is much reduced for patients with markedly reduced life expectancies: Imaging justification and optimization criteria for patients with substantially reduced life expectancies should not necessarily be the same as for those with normal life expectancies.
Radiology 07/2011; 261(1):193-8. · 5.73 Impact Factor
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ABSTRACT: The goal of this study was to compare patterns of downstream testing and procedures after stress testing with imaging performed at physician offices versus at hospital-outpatient facilities
Stress testing with imaging has grown dramatically in recent years, but whether the location of where the test is performed correlates with different patterns for subsequent cardiac testing and procedures is unknown
We identified 82,178 adults with private health insurance from 2005 to 2007 who underwent ambulatory myocardial perfusion imaging (MPI) or stress echocardiography (SE). Subsequent MPI, SE, cardiac catheterization or revascularization within 6 months was compared between physician office and hospital outpatient settings.
Overall, 85.1% of MPI and 84.9% of SE were performed in physician offices. The proportion of patients who underwent subsequent MPI, SE, or cardiac catheterization was not statistically different between physician office and hospital outpatient settings for MPI (14.2% vs. 13.9%, p=0.44) or SE (7.9% vs. 8.6%, p=0.21). However, patients with physician office imaging had slightly higher rates of repeat MPI within 6 months compared with hospital-outpatient imaging for both index MPI (3.5% vs. 2.0%, p<0.001) and SE (3.4% vs. 2.1%, p<0.001), and slightly lower rates of cardiac catheterization after index MPI (11.4% vs. 12.2%, p=0.04) and SE (4.5% vs. 7.0%, p<0.001). Differences in 6-month utilization were observed across the 5 healthcare markets after index MPI but not after index SE CONCLUSIONS: Physician office imaging is associated with slightly higher repeat MPI and fewer cardiac catheterizations than hospital outpatient imaging, but no overall difference in the proportion of patients undergoing additional further testing or procedures. Although regional variation exists, especially for MPI, the relationship between physician office location of stress testing with imaging and greater downstream resource utilization appears modest.
JACC. Cardiovascular imaging 06/2011; 4(6):630-7. · 14.29 Impact Factor
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Tuba Khawaja,
Christine Greer,
Aalap Chokshi,
Nelson Chavarria,
Samir Thadani,
Meaghan Jones,
Kenneth Schaefle,
Ketan Bhatia,
J Elias Collado,
Daichi Shimbo, Andrew J Einstein,
P Christian Schulze
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ABSTRACT: Epicardial adipose tissue has been linked to cardiovascular metabolism and inflammation and has been shown to predict prevalence and progression of coronary artery disease. Only limited data are available on the role of epicardial fat in patients with heart failure (HF). We analyzed cardiac adiposity and its relation to markers of morbidity and clinical outcome in patients with normal and impaired left ventricular (LV) function. Epicardial fat volume (EFV) and coronary artery calcium were measured in 381 patients (210 women and 171 men, mean age 55 ± 10 years) who underwent low-dose computed tomography. HF was defined by LV ejection fraction (EF) <55%. Three hundred twenty-one patients had an EF >55% (mean 63 ± 6) and 60 patients had an EF <55% (mean 41 ± 12). Subgroup analysis was performed according to degree of LV dysfunction in patients with HF (LVEF 35% to 55% or <35%). Mean EFVs were 114.5 ± 98.5 cm(3) in patients with normal EF and 83.5 ± 67.1 cm(3) in those with decreased EF (p <0.05). Mean EFVs were 96.1 ± 73.9 cm(3) in patients with moderate HF and 52.2 ± 29.7 cm(3) in patients with severe HF (p <0.05). Subgroup analysis revealed a persistently smaller EFV in patients with HF regardless of coronary artery calcium scores, markers of renal function, lipid metabolism, fasting blood glucose, or body mass index. In conclusion, our data demonstrate a stepwise decrease in EFV in patients with impaired cardiac function.
The American journal of cardiology 05/2011; 108(3):397-401. · 3.58 Impact Factor
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ABSTRACT: Complex fractionated atrial electrograms (CFAE) are morphologically more uniform in persistent longstanding as compared with paroxysmal atrial fibrillation (AF). It was hypothesized that this may result from a greater degree of repetitiveness in CFAE patterns at disparate left atrial (LA) sites in longstanding AF.
CFAEs were obtained from recording sites outside the 4 pulmonary vein (PV) ostia and at a posterior and an anterior LA site during paroxysmal and longstanding persistent AF (10 patients each, 120 sequences total). To quantify repetitiveness in CFAE, the dominant frequency was measured from ensemble spectra using 8.4-second sequences, and repetitiveness was calculated by 2 novel techniques: linear prediction and Fourier reconstruction methods. Lower prediction and reconstruction errors were considered indicative of increasing repetitiveness and decreasing randomness. In patients with paroxysmal AF, CFAE pattern repetitiveness was significantly lower (randomness higher) at antral sites outside PV ostia as compared with LA free wall sites (P < 0.001). In longstanding AF, repetitiveness increased outside the PV ostia, especially outside the left superior PV ostium, and diminished at the LA free wall sites. The result was that in persistent AF, there were no significant site-specific differences in CFAE repetitiveness at the selected LA locations used in this study. Average dominant frequency magnitude was 5.32 ± 0.29 Hz in paroxysmal AF and higher in longstanding AF, at 6.27 ± 0.13 Hz (P < 0.001), with the frequency of local activation approaching a common upper bound for all sites.
In paroxysmal AF, CFAE repetitiveness is low and randomness high outside the PVs, particularly the left superior PV. As evolution to persistent longstanding AF occurs, CFAE repetitiveness becomes more uniformly distributed at disparate sites, possibly signifying an increasing number of drivers from remote PVs.
Circulation Arrhythmia and Electrophysiology 05/2011; 4(4):470-7. · 6.46 Impact Factor
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ABSTRACT: In light of recent focus on diagnostic imaging, cardiac SPECT imaging needs to become a shorter test with lower radiation exposure to patients. Recently introduced Cadmium Zinc Telluride (CZT) cameras have the potential to achieve both goals.
During a 2-month period patients presenting for a Tc-99m sestamibi SPECT MPI study were imaged using a CZT camera using a low-dose rest-stress protocol (5 mCi rest and 15 mCi stress doses). Patients ≥250 lbs or a BMI ≥35 kg/m(2) were excluded. Rest images were processed at 5- and 8-minute acquisition times and stress images at 3- and 5-minute acquisition times. A subset of patients had stress imaging performed using both conventional and CZT SPECT cameras. Image acquisition times and SPECT camera images were compared based on total counts, count rate, image quality, and summed rest and stress scores. Twelve month clinical follow-up was also obtained.
131 patients underwent the study protocol (age 64.9 ± 9.8 years, 54.2% male). There was no significant difference in image quality and mean summed scores between 5- and 8-minute rest images and between 3- and 5-minute stress images. When compared to a conventional SPECT camera in 27 patients, total rest and stress perfusion deficits and calculated LVEF were similar (r = 0.94 and 0.96, respectively). At 12 months there was a benign prognosis in patients with normal perfusion. The effective dose was 5.8 mSv for this protocol which is 49.2% less than conventional Tc-99m studies and 75.7% less than conventional Tl-201/Tc-99m dual isotope studies.
New SPECT camera technology with low isotope dose significantly reduces ionizing radiation exposure and imaging times compared to traditional protocols while maintaining image quality and diagnostic accuracy.
Journal of Nuclear Cardiology 04/2011; 18(5):847-57. · 2.67 Impact Factor
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Journal of Nuclear Cardiology 03/2011; 18(3):385-92. · 2.67 Impact Factor
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ABSTRACT: Triple-rule-out computed tomographic angiography (TRO CTA), performed to evaluate the coronary arteries, pulmonary arteries, and thoracic aorta, has been associated with high radiation exposure. The use of sequential scanning for coronary computed tomographic angiography reduces the radiation dose. The application of sequential scanning to TRO CTA is much less well defined. We analyzed the radiation dose and image quality from TRO CTA performed at a single outpatient center, comparing the scans from a period during which helical scanning with electrocardiographically controlled tube current modulation was used for all patients (n = 35) and after adoption of a strategy incorporating sequential scanning whenever appropriate (n = 35). Sequential scanning was able to be used for 86% of the cases. The sequential-if-appropriate strategy, compared to the helical-only strategy, was associated with a 61.6% dose decrease (mean dose-length product of 439 mGy × cm vs 1,144 mGy × cm and mean effective dose of 7.5 mSv vs 19.4 mSv, respectively, p <0.0001). Similarly, a 71.5% dose reduction occurred among the 30 patients scanned with the sequential protocol compared to the 40 patients scanned with the helical protocol using either strategy (326 mGy × cm vs 1,141 mGy × cm and 5.5 mSv vs 19.4 mSv, respectively, p <0.0001). Although the image quality did not differ between the strategies, a nonstatistically significant trend was seen toward better quality in the sequential protocol than in the helical protocol. In conclusion, approaching TRO CTA with a diagnostic strategy of sequential scanning, as appropriate, can offer a marked reduction in the radiation dose while maintaining the image quality.
The American journal of cardiology 02/2011; 107(7):1093-8. · 3.58 Impact Factor
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ABSTRACT: To determine population-based rates of the use of diagnostic imaging procedures with ionizing radiation in children, stratified by age and sex.
Retrospective cohort analysis.
All settings using imaging procedures with ionizing radiation.
Individuals younger than 18 years, alive, and continuously enrolled in UnitedHealthcare between January 1, 2005, and December 31, 2007, in 5 large US health care markets.
Number and type of diagnostic imaging procedures using ionizing radiation in children.
A total of 355 088 children were identified; 436 711 imaging procedures using ionizing radiation were performed in 150 930 patients (42.5%). The highest rates of use were in children older than 10 years, with frequent use in infants younger than 2 years as well. Plain radiography accounted for 84.7% of imaging procedures performed. Computed tomographic scans-associated with substantially higher doses of radiation-were commonly used, accounting for 11.9% of all procedures during the study period. Overall, 7.9% of children received at least 1 computed tomographic scan and 3.5% received 2 or more, with computed tomographic scans of the head being the most frequent.
Exposure to ionizing radiation from medical diagnostic imaging procedures may occur frequently among children. Efforts to optimize and ensure appropriate use of these procedures in the pediatric population should be encouraged.
Archives of pediatrics & adolescent medicine 01/2011; 165(5):458-64. · 3.73 Impact Factor
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Jacc-cardiovascular Imaging. 01/2011; 4(6):630-637.
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ABSTRACT: Myocardial perfusion imaging (MPI) is the single medical test with the highest radiation burden to the US population. Although many patients undergoing MPI receive repeat MPI testing, or additional procedures involving ionizing radiation, no data are available characterizing their total longitudinal radiation burden and relating radiation burden with reasons for testing.
To characterize procedure counts, cumulative estimated effective doses of radiation, and clinical indications for patients undergoing MPI.
A retrospective cohort study of 1097 consecutive patients undergoing index MPI during the first 100 days of 2006 (January 1-April 10) at Columbia University Medical Center, New York, New York, that evaluated all preceding medical imaging procedures involving ionizing radiation undergone beginning October 1988, and all subsequent procedures through June 2008, at the center.
Cumulative estimated effective dose of radiation, number of procedures involving radiation, and indications for testing.
Patients underwent a median of 15 (interquartile range [IQR], 6-32; mean, 23.9) procedures involving radiation exposure; of which 4 (IQR, 2-8; mean, 6.5) were high-dose procedures (≥3 mSv; ie, 1 year's background radiation), including 1 (IQR, 1-2; mean, 1.8) MPI study per patient. A total of 344 patients (31.4%) received cumulative estimated effective dose from all medical sources of more than 100 mSv. Multiple MPIs were performed in 424 patients (38.6%), for whom cumulative estimated effective dose was 121 mSv (IQR, 81-189; mean, 149 mSv). Men and white patients had higher cumulative estimated effective doses. More than 80% of initial and 90% of repeat MPI examinations were performed in patients with known cardiac disease or symptoms consistent with it.
In this institution, multiple testing with MPI was common and in many patients associated with high cumulative estimated doses of radiation.
JAMA The Journal of the American Medical Association 11/2010; 304(19):2137-44. · 30.03 Impact Factor
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ABSTRACT: We sought to evaluate the accuracy and reproducibility of visual estimation of coronary artery calcium (CAC) from computed tomography attenuation correction (CTAC) scans performed for hybrid positron emission tomography (PET)/computed tomography (CT) and single-photon emission computed tomography (SPECT)/CT myocardial perfusion imaging (MPI).
At the time of MPI, hybrid systems obtain a low-dose, non-electrocardiogram (ECG)-gated CT scan that is used to perform attenuation correction. Utility of this CTAC scan in estimating actual CAC as measured by Agatston score (AS) on standard ECG-gated scans has not been previously studied.
A total of 492 patients, from 3 centers, receiving both MPI with CTAC and a standard CAC scan were studied. At each site, experienced readers blinded to AS reviewed CTAC images, visually estimating CAC on a 6-level scale: classifying patients as estimated AS of 0, 1 to 9, 10 to 99, 100 to 300, 400 to 999, or ≥1,000. Agreement between visually estimated coronary artery calcium (VECAC) on CTAC and AS, measured standardly and converted to the same scale, was evaluated, as was inter-reader agreement.
Although CTAC images are low dose and nongated, a high degree of association was observed between VECAC and AS, with 63% of VECACs in the same category as the AS category and 93% within 1 category. Weighted kappa was 0.89 (95% confidence interval: 0.88 to 0.91, p < 0.0001). High weighted kappa statistics were observed for each site, scanner type, and sex. Readers reported identical scores in 65% of cases and scores within 1 category in 93%.
CAC can be visually assessed from low-dose CTAC scans with high agreement with AS. CTAC scans should be routinely assessed for VECAC.
Journal of the American College of Cardiology 11/2010; 56(23):1914-21. · 14.16 Impact Factor
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ABSTRACT: The purpose of this study was to describe radiation exposure from cardiac imaging procedures over time in a general population.
Cardiac imaging procedures frequently expose patients to ionizing radiation, but their contribution to effective doses of radiation in the general population is unknown.
We used administrative claims to identify cardiac imaging procedures performed from 2005 to 2007 in 952,420 nonelderly insured adults in 5 U.S. health care markets. We estimated 3-year cumulative effective doses of radiation in millisieverts from these procedures We then calculated population-based annual rates of radiation exposure to effective doses < or =3 mSv/year (background level of radiation from natural sources), >3 to 20 mSv/year, or >20 mSv/year (upper annual limit for occupational exposure averaged over 5 years).
A total of 90,121 (9.5%) individuals underwent at least 1 cardiac imaging procedure using radiation. Among patients who underwent > or =1 cardiac imaging procedures, the mean cumulative effective dose over 3 years was 23.1 mSv (range 1.5 to 543.7 mSv). Myocardial perfusion imaging accounted for 74% of the cumulative effective dose. Overall, 47.8% of cardiac imaging procedures were performed in physician offices; this proportion was higher for myocardial perfusion imaging (74.8%) and cardiac computed tomography studies (76.5%). The annual population-based rate of receiving an effective dose of >3 to 20 mSv/year was 89.0 per 1,000; and 3.3 per 1,000 for cumulative doses >20 mSv/year. Annual effective doses increased with age and were generally higher among men.
Cardiac imaging procedures lead to substantial radiation exposure and effective doses for many patients in the U.S.
Journal of the American College of Cardiology 08/2010; 56(9):702-11. · 14.16 Impact Factor
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Andrew J Einstein
Archives of internal medicine 07/2010; 170(13):1175; author reply 1175-6. · 11.46 Impact Factor
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ABSTRACT: Two-step targeting with bispecific antibody and Tc-labeled high-specific radioactivity polymers was used for molecular imaging of two very small model lesions in rats.
Sprague-Dawley rats (group I) were injected with surrogate antigen-coated beads (SA beads) in the right hind leg or unmodified beads in the contralateral hind leg. In group II, femoral artery de-endothelialization was induced in the left hind leg and sham operation was performed in the contralateral hind leg. Bispecific antibody Z2D3 F(ab')2-anti-DTPA F(ab')2 was injected intravenously 24 h after SAB injection or 1 week after endothelial denudation. Tc-labeled polymers were injected intravenously 24 h later and gamma-images obtained at 2 and 24 h in group I or approximately 2.5 h in group II. Lesions were visualized by 2 h. In group I, SA beads-specific uptake in muscles was significantly greater than with unmodified beads (P<0.015). In group II, lesions were visualized by 2.5 h after radiopolymer injection with uptake activity 2.1+/-0.6 times greater than in the contralateral side from in-vivo images (P<0.004) and 1.8+/-0.7 times by gamma-scintillation counting (P<0.04).
Pretargeting with Z2D3 bispecific antibody for the localization of radiolabeled polymers enabled successful in-vivo gamma-imaging of very small lesions in two rat models of extravascular and intravascular targets. Biodistribution data confirmed that pretargeting with bispecific antibody enabled targeted visualization of two different very small model lesions by in-vivo gamma-imaging.
Nuclear Medicine Communications 04/2010; 31(4):320-7. · 1.40 Impact Factor
