Perioperative Cardiovascular Risk Assessment and Management in Liver Transplant Recipients: A Review of the Literature Merging Guidelines and Interventions.

Liver transplantation (LT) is the second most performed solid organ transplant. Coronary artery disease (CAD) is a critical consideration for LT candidacy, particularly in patients with known CAD or risk factors, including metabolic dysfunction associated with steatotic liver disease. The presence of severe CAD may exclude patients from LT; therefore, precise preoperative evaluation and interventions are necessary to achieve transplant candidacy. Cardiovascular complications represent the earliest nongraft-related cause of death post-transplantation. Timely intervention to reduce cardiovascular events depends on adequate CAD screening. Coronary disease screening in end-stage liver disease is challenging because standard noninvasive CAD screening tests have low sensitivity due to hyperdynamic state and vasodilatation. As a result, there is overuse of invasive coronary angiography to exclude severe CAD. Coronary artery calcium scoring using a computed tomography scan is a tool for the prediction of cardiovascular events, and can be used to achieve risk stratification in LT candidates. Recent literature shows that qualitative assessment on both noncontrast- and contrast-enhanced chest computed tomography can be used instead of calcium score to assess the presence of coronary calcium. With increasing prevalence, protocols to address CAD in LT candidates must be reconsidered. Percutaneous coronary intervention could allow a shorter duration of dual-antiplatelet therapy in simple lesions, with safer perioperative outcomes. Hybrid coronary revascularization is an option for high-risk LT candidates with multivessel disease nonamenable to percutaneous coronary intervention. The objective of this review is to evaluate existing methods for preoperative cardiovascular risk stratification, and to describe interventions before surgery to optimize patient outcomes and reduce cardiovascular event risk.

Promoting Equity, Diversity, and Inclusion in Medicine: A Comprehensive Toolkit for Change in Radiology.

This toolkit presents a comprehensive framework for a toolkit intended to increase equity, diversity, and inclusion (EDI) within the medical field and recommendations. We advocate for clear, comprehensive definitions and interpretations of fundamental EDI terms, laying the groundwork necessary for initiating and maintaining EDI initiatives. Furthermore, we offer a systematic approach to establishing EDI committees within medical departments, accentuating the pivotal role these committees play as they drive and steer EDI strategies. This toolkit also explores strategies tailored for the recruitment of a diverse workforce. This includes integral aspects such as developing inclusive job advertisements, implementing balanced search methods for candidates, conducting unbiased appraisals of applications, and structuring diverse hiring committees. The emphasis on these strategies not only augments the diversity within medical institutions but also sets the stage for a more holistic approach to healthcare delivery. Therefore, by adopting the recommended strategies and guidelines outlined in this framework, medical institutions and specifically radiology departments can foster an environment that embodies inclusivity and equity, thereby enhancing the quality of patient care and overall health outcomes.

Core and Advanced Thoracic Imaging Curricula to Guide Residency and Fellowship Training: A Framework From the Canadian Society of Thoracic Radiology.

RATIONALE: A well-defined curriculum with goals and objectives is an inherent part of every radiology training program. MATERIALS AND METHODS: Following a needs assessment, the Canadian Society of Thoracic Radiology Education Committee developed a thoracic imaging curriculum using a mixed- method approach, complimentary to the cardiac curriculum published as a separate document. RESULTS: The Thoracic Imaging Curriculum consists of two separate yet complimentary parts: a Core Curriculum, aimed at residents in-training, with the main goal of building a strong foundational knowledge, and an Advanced Curriculum, designed to build upon the core knowledge and guide a more in-depth subspecialty training. CONCLUSION: The curricular frameworks aim to enhance the educational experience of residents and fellows and provide an educational framework for clinical supervisors and residency and fellowship program directors. SUMMARY STATEMENT: The Canadian Society of Thoracic Radiology championed the creation of Cardiovascular and Thoracic Imaging curricula encompassing clinical knowledge and technical, communication, and decision-making skills with the goal of providing direction to a strong foundational knowledge for residents and to guide specialty training for fellowship programs.

Computed Tomography Angiography Assessment of Acute Aortic Syndromes: Classification, Differentiating Imaging Features, and Imaging Interpretation Pitfalls.

An acute aortic syndrome (AAS) is an important life-threatening condition that requires early detection and management. Acute intramural hematoma (IMH), aortic dissection (AD) and penetrating atherosclerotic ulcer (PAU) are included in AAS. ADs can be classified using the well-known Stanford or DeBakey classification systems. However, these classification systems omit description of arch dissections, anatomic variants, and morphologic features that impact outcome. The Society for Vascular Surgery and Society of Thoracic Surgeons (SVS-STS) have recently introduced a classification system that classifies ADs according to the location of the entry tear (primary intimomedial tear, PIT) and the proximal and distal extent of involvement, but does not include description of all morphologic features that may have diagnostic and prognostic significance. This review describes these classification systems for ADs and other AAS entities as well as their limitations. Typical computed tomography angiography (CTA) imaging appearance and differentiating features of ADs, limited intimal tears (LITs), IMHs, intramural blood pools (IBPs), ulcer-like projections (ULPs), and PAUs will be discussed. Furthermore, this review highlights common imaging interpretation pitfalls, what should be included in a comprehensive CTA report, and provides a brief overview of current management options.

Diagnostic performance of chest radiography measurements for the assessment of cardiac chamber enlargement.

BACKGROUND: The cardiothoracic ratio (CTR) is commonly assessed on chest radiography for detection of cardiac chamber enlargement, but the traditional cutpoint of 0.5 has low specificity. We sought to evaluate the diagnostic accuracy of new measurement techniques for the detection of cardiac enlargement on chest radiographs. METHODS: We obtained retrospective cross-sectional data on consecutive patients who underwent both chest radiography and cardiac magnetic resonance imaging (MRI) within a 14-day interval between 2006 and 2016 at a large academic hospital network. We established the presence of cardiac chamber enlargement using cardiac MRI as the reference standard. We evaluated the diagnostic performance of different techniques for measuring heart size and CTR on frontal chest radiographs. RESULTS: Of 152 patients included, 81 (53%) were men and the mean age was 52 years. Maximum heart diameter had the highest area under the receiver operating characteristic curve for detection of cardiac enlargement (0.827, 95% confidence interval 0.760-0.894). In the subgroup of posteroanterior chest radiography studies (n = 101), a CTR cutpoint of 0.50 had only moderate sensitivity (72%) and specificity (72%). In men, a maximum heart diameter cutpoint of 15 cm had a sensitivity of 86% and a negative likelihood ratio of 0.24, and a cutpoint of 19 cm had a specificity of 100% and a positive likelihood ratio of infinity. In women, a maximum heart diameter cutpoint of 13 cm had a sensitivity of 91% and a negative likelihood ratio of 0.15, and a cutpoint of 17 cm had a specificity of 91% and a positive likelihood ratio of 3.5. INTERPRETATION: A traditional CTR cutpoint of 0.5 has limited diagnostic value. Simple heart diameter measurements have higher diagnostic performance measures than CTR.

Multimodality Assessment of Thoracic Aortic Dimensions: Comparison of Computed Tomography Angiography, Magnetic Resonance Imaging, and Echocardiography Measurements.

PURPOSE: The purpose of this study was to compare thoracic aortic measurements between computed tomography (CT), magnetic resonance imaging (MRI), and transthoracic echocardiography (TTE). MATERIALS AND METHODS: A total of 127 patients (mean age: 45±18 y, 49% male) who had undergone CT and MRI evaluation of the thoracic aorta at a single tertiary referral hospital within a 6-month interval between 2007 and 2017 were included in this retrospective study. TTE studies performed within the same 6-month interval were also evaluated. Thoracic aortic measurements were blindly evaluated using multiple techniques and were compared between modalities. RESULTS: There was no significant difference in maximum aortic root diameter between CT and MRI when using the inner lumen-to-inner lumen technique (mean difference: 0.2±1.4 mm, P=0.51) or the outer lumen-to-outer lumen technique (mean difference: 0.5±1.4 mm, P=0.07). There were no significant differences between CT and MRI at any other level except for the distal descending aorta (20.2±4.6 vs. 19.8±4.6 mm, P<0.001). However, aortic root measurements by TTE using the leading edge-to-leading edge technique were significantly smaller compared with maximum aortic root diameters using the inner lumen-to-inner lumen and outer lumen-to-outer lumen techniques by both CT (mean difference: 4.9±2.7 mm, P<0.001 and 7.4±2.8 mm, P<0.001, respectively) and MRI (mean difference: 4.8±3.2 mm, P<0.001 and 8.2±3.0 mm, P<0.001, respectively). CONCLUSIONS: There is excellent agreement in thoracic aortic measurements between CT and MRI. However, TTE significantly underestimates maximum aortic root diameter compared with CT and MRI. Therefore, caution should be used when interpreting small apparent changes in aortic root diameters between TTE and CT or MRI.

Diagnostic Accuracy of Sex-Specific Chest CT Measurements Compared With Cardiac MRI Findings in the Assessment of Cardiac Chamber Enlargement.

OBJECTIVE: The purpose of this study was to establish sex-specific chest CT measurement thresholds for detection of cardiac chamber enlargement with cardiac MRI as the reference standard. MATERIALS AND METHODS: Consecutive patients who underwent contrast-enhanced chest CT (64- or 320-MDCT) and cardiac MRI within a 7-day interval between August 2006 and August 2016 were included in this retrospective study (n = 217; 115 men, 102 women; mean age, 52.8 ± 15.8 years). Measurements were performed on axial CT images to evaluate right atrial (RA), right ventricular (RV), left atrial (LA), and left ventricular (LV) chamber size. The presence of chamber enlargement (RAE, RVE, LAE, and LVE) was established with cardiac MRI as the reference standard. ROC analysis was performed. Optimal sex-specific CT measurement thresholds were identified that ensured specificity of 90% or greater and maximized sensitivity. RESULTS: The prevalence of chamber enlargement in men was 26% for RAE, 11% for RVE, 40% for LAE, and 24% for LVE. In women the prevalence was 16% for RAE, 15% for RVE, 27% for LAE, and 12% for LVE. The following CT measurement thresholds were optimal: for RAE, RA transverse diameter ≥ 67 mm for men (AUC, 0.825) and ≥ 64 mm for women (AUC, 0.926); for RVE, RV transverse diameter ≥ 60 mm for men (AUC, 0.846) and ≥ 57 mm for women (AUC, 0.858); for LAE, LA anteroposterior diameter ≥ 50 mm for men (AUC, 0.795) and ≥ 45 mm for women (AUC, 0.841); for LVE, LV transverse diameter ≥ 58 mm for men (AUC, 0.917) and ≥ 53 mm for women (AUC, 0.840). CONCLUSION: Cardiac chamber enlargement can be identified with high specificity and reasonable sensitivity on axial chest CT images by use of sex-specific measurement thresholds.

Magnetic resonance assessment of pulmonary (QP) to systemic (QS) flows using 4D phase-contrast imaging: pilot study comparison with standard through-plane 2D phase-contrast imaging.

RATIONALE AND OBJECTIVES: To investigate four-dimensional (4D) phase-contrast (PC) magnetic resonance (MR) in the evaluation of intracardiac shunts by simultaneous assessment of pulmonary (QP) and systemic (QS) flows in a pilot study and to compare results to through-plane two-dimensional (2D) PC MR. MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained. Nineteen patients with suspected intracardiac shunts underwent cardiac MR at 1.5T. Assessments of QP and QS were performed using free-breathing retrospectively gated 2D PC gradient recalled echo (GRE; 1.6 × 1.6 × 5 mm(3)) imaging with one-dimensional through-plane velocity encoding gradient (venc = 150 cm/s) in consecutive measurements for the main pulmonary artery (MPA) and ascending aorta (AA), respectively. A prospectively triggered 4D PC GRE technique (2.4 × 1.8 × 3 mm(3)) with three orthogonal venc directions was also used with volume coverage of both MPA and AA. RESULTS: QP and QS assessed by 4D PC correlated with 2D PC acquisitions (r = 0.92 and r = 0.67 respectively; P < .0001 for both) but demonstrated significant underestimation of individual flow volumes (-21.9 ± 12.2 mL; P < .0001 and -10.7 ± 13.1 mL; P = .0023, respectively). Calculated QP:QS ratios demonstrated high correlation (r = 0.78; P < .0001) and no significant differences between 4D PC and 2D PC acquisitions (-0.09 ± 0.24, P = .14). Image acquisition times for 2D PC assessment of QP and QS were 2.98 ± 0.52 and 2.84 ± 0.50 minutes, respectively (P = .038), whereas time to acquire 4D PC images was significantly longer, 18.75 ± 4.58 minutes (P < .001). CONCLUSIONS: Four-dimensional PC MR imaging allows for accurate assessment of QP:QS ratios in the evaluation of intracardiac shunts while absolute flow volumes demonstrate offsets. Further refinement of the technique with improvement in acquisition times may be required before widespread clinical implementation.

Accuracy of right and left ventricular functional assessment by short-axis vs axial cine steady-state free-precession magnetic resonance imaging: intrapatient correlation with main pulmonary artery and ascending aorta phase-contrast flow measurements.

OBJECTIVE: The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations. METHODS: A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output. RESULTS: There was a high linear correlation between MPA-PC flow and RV-stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and -2.3 mL for RV-short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis-LV SV and short-axis-RV SV. CONCLUSION: No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes.

Assessment of right ventricular volumes and function using cardiovascular magnetic resonance cine imaging after atrial redirection surgery for complete transposition of the great arteries.

Cardiovascular magnetic resonance (CMR) imaging is the reference standard for measurement of right ventricular (RV) volumes and function. To date, no study has compared methods of data acquisition and analysis by CMR for adults with a systemic RV. Our objective was to evaluate RV size and function using axial and short axis views in adults post atrial switch (Mustard) surgery. A total of 34 adults (20 male, mean age at CMR 32 ± 6 years) were identified at our centre. Volumes, RV end-diastolic (EDV) and end-systolic (ESV) were measured in short axis and axial orientations by two independent experienced readers, blinded to clinical and CMR data. Intra and interobserver measurements in each view were compared using Bland-Altman plots and intraclass correlation coefficients (ICC). Although mean volumes were larger in the axial as compared with the short axis view [RVEDV 247 ± 67 vs. 233 ± 54 ml (p = 0.002) and RVESV 148 ± 54 vs. 136 ± 50 ml (p = 0.001)], mean RV ejection fractions (EF) were similar [41 ± 9 % vs. 43 ± 12 % (p = 0.13)]. Bland-Altman plots demonstrated better agreement for axial measures of RVEDV and right ventricular ejection fraction (RVEF) within and between observers. Similarly, ICC values were stronger for axial as compared with short axis volumes and function-intraobserver RVEDV 0.99 (0.98-0.99) versus 0.96 (0.92-0.98) and RVEF 0.96 (0.93-0.98) versus 0.90 (0.82-0.95); interobserver RVEDV 0.97 (0.94-0.98) versus 0.90 (0.73-0.95) and RVEF 0.85 (0.53-0.94) versus 0.82 (0.67-0.90). Axially derived measurements of RV volumes and function have better agreement and reproducibility as compared with short axis values; whereas axial volumes tend to be larger, RVEF is not significantly different between the two methods.

Cardiac magnetic resonance imaging and the assessment of ebstein anomaly in adults.

No published studies have evaluated the role of cardiac magnetic resonance (CMR) imaging for the assessment of Ebstein anomaly. Our objective was to evaluate the right heart characteristics in adults with unrepaired Ebstein anomaly using contemporary CMR imaging techniques. Consecutive patients with unrepaired Ebstein anomaly and complete CMR studies from 2004 to 2009 were identified (n = 32). Volumetric measurements were obtained from the short-axis and axial views, including assessment of the functional right ventricular (RV) end-diastolic volume (EDV) and end-systolic volume. The volume of the atrialized portion of the right ventricle in end-diastole was calculated as the difference between the total RVEDV and the functional RVEDV. The reproducibility of the measurements in the axial and short-axis views was determined within and between observers. The median value derived from the short-axis and axial views was 136 ml/m(2) (range 59 to 347) and 136 ml/m(2) (range 63 to 342) for the functional RVEDV, 153 ml/m(2) (range 64 to 441) and 154 ml/m(2) (range 67 to 436) for the total RVEDV, 49% (range 32% to 46%) and 50% (range 40% to 64%) for the functional RV ejection fraction, respectively. The axial measurements demonstrated lower intraobserver and interobserver variability than the short-axis approach for all values, with the exception of the intraobserver functional RVEDV and interobserver total RVEDV for which the limits of agreement and variance were not significantly different between the 2 views. In conclusion, measurements of right heart size and systolic function in patients with Ebstein anomaly can be reliably achieved using CMR imaging. Axial imaging appeared to provide more reproducible data than that obtained from the short-axis views.