ACR clinical statement on noninvasive cardiac imaging

The cardiac conundrum: a systematic review and bibliometric analysis of authorship in cardiac magnetic resonance imaging studies

PURPOSE

We aimed to assess the role of radiologists, cardiologists, and other medical and non-medical figures in cardiac magnetic resonance imaging (MRI) research in the last 34 years, focusing on first and last authorship, number of published studies, and journal impact factors (IF).

METHODS

Articles in the field of cardiac MRI were considered in this systematic review and retrospective bibliometric analysis. For included studies, the first and last authors were categorized as cardiologists, radiologists/nuclear medicine physicians, medical doctors (MD) with specialties in both cardiology and radiology/nuclear medicine, and other MD and non-MD. Differences in the number of papers published overall and by year and institution location for the first and last author category were assessed. Mean IF differences between author categories were also investigated.

RESULTS

A total of 2053 articles were included in the final analysis. For the first authors (n = 2011), 52% were cardiologists, 22% radiologists/nuclear medicine physicians, 16% other MD, 10% other non-MD, and 1% both cardiologists and radiologists/nuclear medicine physicians. Similarly, the last authors (n = 2029) resulted 54% cardiologists, 22% radiologists/nuclear medicine physicians, 15% other MD, 8% other non-MD, and 2% both cardiologists and radiologists/nuclear medicine physicians. No significant differences due to institution location in the first and last authorship proportions were found. Average journal IF was significantly higher for cardiologist first and last authors when compared to that of radiologists/nuclear medicine physicians (both p < 0.0001).

CONCLUSION

Over 50% of studies in the field of cardiac MRI published in the last 34 years are conducted by cardiologists.

Cardiac imaging training in radiology residency programs: a survey of radiology chief residents

RATIONALE AND OBJECTIVES

Comprehensive training in cardiac imaging during radiology residency is imperative if radiologists are to maintain a significant role in this rapidly growing field. In this study, radiology chief residents were surveyed to assess the current status of cardiac imaging training in radiology residency programs. The responses to this survey may be helpful in understanding current trends in cardiac imaging training and how such training can be improved in the future.

MATERIALS AND METHODS

Chief residents at accredited radiology residency programs were sent an e-mail with a link to a 17-question Web-based survey. The survey assessed the organization of cardiac imaging training in each residency program, imaging modalities incorporated into cardiac imaging training, the role of residents on cardiac imaging rotations, and attitudes of residents about their cardiac imaging training and the future of cardiac imaging.

RESULTS

Responses were obtained from 52 of 112 (46%) programs. Seventy-one percent had at least one dedicated cardiac imaging rotation during their residencies. Fifty-two percent and 62% of respondents reported <5 hours of cardiac imaging-related case conferences and didactic lectures per year, respectively. Most had cardiac computed tomography or magnetic resonance imaging incorporated into their cardiac imaging training. Although 92% felt that cardiac imaging training is important, only 17% felt that they currently received adequate training in cardiac imaging.

CONCLUSIONS

The majority of residency programs represented in this survey had at least one dedicated cardiac imaging rotation for their residents. Most of these programs had few cardiac imaging-related conferences and lectures per year. Although most chief residents believed that cardiac imaging training is important, only a minority felt that they currently received adequate training in cardiac imaging.

Initial evaluation of coronary images from 320-detector row computed tomography

PURPOSE

To evaluate image quality and contrast opacification from coronary images acquired from 320-detector row computed tomography (CT). Patient dose is estimated for prospective and retrospective ECG-gating; initial correlation between 320-slice CT and coronary catheterization is illustrated.

METHODS

Retrospective image evaluation from forty consecutive patients included subjective assessment of image quality and contrast opacification (80 ml iopamidol 370 mg I/ml followed by 40 ml saline). Region of interest opacification measurements at the ostium and at 2.5 mm diameter were used to determine the gradient of contrast opacification (defined as the proximal minus distal HU measurements) in coronary arteries imaged in a single heartbeat. Estimated effective dose was compared for prospective versus retrospective ECG-gating, two body mass index categories (30 kg/m(2) cutoff), and single versus two heartbeat acquisition. When available, CT findings were correlated with those from coronary catheterization.

RESULTS

Over 89% of arterial segments (15 segment model) had excellent image quality. The most common reason for image degradation was cardiac motion. One segment in one patient was considered unevaluable. Contrast opacification was almost universally considered excellent. The mean Hounsfield units (HU) was greater than 350; the coronary contrast opacification gradient was 30-50 HU. Patient doses were greater for retrospective ECG-gating, larger patients, and those imaged with two heartbeats. For the most common (n=25) protocol (120 kV, 400 mA, prospective ECG-gating, 60-100% phase window, 16 cm craniocaudal coverage, single heartbeat), the mean dose was 6.8+/-1.4 mSv. All CT findings were confirmed in the four patients who underwent coronary catheterization.

CONCLUSION

Initial 320-detector row coronary CT images have consistently excellent quality and iodinated contrast opacification. These patients were scanned with conservative protocols with respect to iodine load, prospective ECG-gating phase window, and craniocaudal coverage. Future work will focus on lowering contrast and radiation dose while maintaining image quality.