Publications by authors named "Jonathan C L Rodrigues"

42 Publications

Chest X-ray in suspected lung cancer is harmful.

Eur Radiol 2021 Aug 30;31(8):6269-6274. Epub 2021 Jan 30.

Department of Radiology, Royal United Hospitals Bath NHS Foundation Trust, Combe Park, Avon, Bath, BA1 3NG, UK.

Objectives: The aim of this study was to analyse the use of the chest radiograph (CXR) as the first-line investigation in primary care patients with suspected lung cancer.

Methods: Of 16,945 primary care referral CXRs (June 2018 to May 2019), 1,488 were referred for suspected lung cancer. CXRs were coded as follows: CX1, normal but a CT scan is recommended to exclude malignancy; CX2, alternative diagnosis; or CX3, suspicious for cancer. Kaplan-Meier survival analysis was undertaken by stratifying patients according to their CX code.

Results: In the study period, there were 101 lung cancer diagnoses via a primary care CXR pathway. Only 10% of patients with a normal CXR (CX1) underwent subsequent CT and there was a significant delay in lung cancer diagnosis in these patients (p < 0.001). Lung cancer was diagnosed at an advanced stage in 50% of CX1 patients, 38% of CX2 patients and 57% of CX3 patients (p = 0.26). There was no survival difference between CX codes (p = 0.42).

Conclusion: Chest radiography in the investigation of patients with suspected lung cancer may be harmful. This strategy may falsely reassure in the case of a normal CXR and prioritises resources to advanced disease.

Key Points: • Half of all lung cancer diagnoses in a 1-year period are first investigated with a chest X-ray. • A normal chest X-ray report leads to a significant delay in the diagnosis of lung cancer. • The majority of patients with a normal or abnormal chest X-ray have advanced disease at diagnosis and there is no difference in survival outcomes based on the chest X-ray findings.
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http://dx.doi.org/10.1007/s00330-021-07708-0DOI Listing
August 2021

Automated calculation of the right ventricle to left ventricle ratio on CT for the risk stratification of patients with acute pulmonary embolism.

Eur Radiol 2021 Aug 18;31(8):6013-6020. Epub 2021 Jan 18.

Department of Radiology, Royal United Hospitals Bath NHS Foundation Trust, Combe Park, Avon, Bath, BA1 3NG, UK.

Objectives: To assess the feasibility and reliability of the use of artificial intelligence post-processing to calculate the RV:LV diameter ratio on computed tomography pulmonary angiography (CTPA) and to investigate its prognostic value in patients with acute PE.

Methods: Single-centre, retrospective study of 101 consecutive patients with CTPA-proven acute PE. RV and LV volumes were segmented on 1-mm contrast-enhanced axial slices and maximal ventricular diameters were derived for RV:LV ratio using automated post-processing software (IMBIO LLC, USA) and compared to manual analysis in two observers, via intraclass coefficient correlation analysis. Each CTPA report was analysed for mention of the RV:LV ratio and compared to the automated RV:LV ratio. Thirty-day all-cause mortality post-CTPA was recorded.

Results: Automated RV:LV analysis was feasible in 87% (n = 88). RV:LV ratios ranged from 0.67 to 2.43, with 64% (n = 65) > 1.0. There was very strong agreement between manual and automated RV:LV ratios (ICC = 0.83, 0.77-0.88). The use of automated analysis led to a change in risk stratification in 45% of patients (n = 40). The AUC of the automated measurement for the prediction of all-cause 30-day mortality was 0.77 (95% CI: 0.62-0.99).

Conclusion: The RV:LV ratio on CTPA can be reliably measured automatically in the majority of real-world cases of acute PE, with perfect reproducibility. The routine use of this automated analysis in clinical practice would add important prognostic information in patients with acute PE.

Key Points: • Automated calculation of the right ventricle to left ventricle ratio was feasible in the majority of patients and demonstrated perfect intraobserver variability. • Automated analysis would have added important prognostic information and altered risk stratification in the majority of patients. • The optimal cut-off value for the automated right ventricle to left ventricle ratio was 1.18, with a sensitivity of 100% and specificity of 54% for the prediction of 30-day mortality.
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http://dx.doi.org/10.1007/s00330-020-07605-yDOI Listing
August 2021

Postoperative cavitating infarction following lobectomy: the importance of variant pulmonary anatomy.

BMJ Case Rep 2020 Dec 9;13(12). Epub 2020 Dec 9.

Radiology Department, Royal United Hospital Bath NHS Trust, Bath, UK.

A 75-year-old woman was admitted to hospital with haemoptysis, fever and shortness of breath. She had undergone a right video-assisted thoracoscopic surgery upper lobectomy for an apical lung cancer 4 weeks earlier, and had been treated with antibiotics for 1 week prior to admission for a suspected postoperative lung abscess. Review of preoperative imaging found that she possessed a lobar pulmonary artery variant, with postoperative imaging confirming that the right lower lobe segmental pulmonary artery had been divided alongside the upper lobe vessels. The diagnosis of a lung abscess was thus revised to a cavitating pulmonary infarct. There are numerous variations of the pulmonary vasculature, all of which have the potential to cause a range of serious vascular complications if not appreciated preoperatively. Measures to mitigate the risk of complications resulting from vascular anomalies should be considered by both radiologists and surgeons, with effective lines of communication essential to safe working.
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http://dx.doi.org/10.1136/bcr-2020-238138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7733089PMC
December 2020

Fulminant immune-mediated necrotising myopathy (IMNM) mimicking myocardial infarction with non-obstructive coronary arteries (MINOCA).

BMJ Case Rep 2020 Nov 2;13(11). Epub 2020 Nov 2.

Radiology Department, Royal United Hospital Bath NHS Trust, Bath, UK

A 74-year-old man, with inflammatory arthritis, recently commenced on adalimumab, presented with a 4-week history of left-sided chest pain, malaise and shortness of breath. Admission ECG showed age-indeterminate left bundle branch block. Troponin T was 4444 ng/L (normal range <15 ng/L) and acute coronary syndrome treatment was commenced. Catheter angiogram revealed mild-burden non-obstructive coronary disease. Cardiac magnetic resonance (CMR) was performed to refine the differential diagnosis and demonstrated no myocardial oedema or late gadolinium enhancement. Extracardiac review highlighted oedema and enhancement of the left shoulder girdle muscles consistent with acute myositis. Creatine kinase was subsequently measured and significantly elevated at 7386 IU/L (normal range 30-200 IU/L in men). Electrophoresis clarified that this was of predominantly skeletal muscle origin. Myositis protocol MRI revealed florid skeletal muscle oedema. The MR findings, together with positive anti-Scl-70 antibodies, suggested fulminant immune-mediated necrotising myopathy presenting as a rare mimic of myocardial infarction with non-obstructive coronary arteries, diagnosed by careful extracardiac CMR review.
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http://dx.doi.org/10.1136/bcr-2020-236603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7607567PMC
November 2020

Reporting incidental coronary, aortic valve and cardiac calcification on non-gated thoracic computed tomography, a consensus statement from the BSCI/BSCCT and BSTI.

Br J Radiol 2021 Jan 29;94(1117):20200894. Epub 2020 Oct 29.

Royal Bournemouth Hospital, Castle Lane East, Bournemouth, UK.

Incidental coronary and cardiac calcification are frequent findings on non-gated thoracic CT. We recommend that the heart is reviewed on all CT scans where it is visualised. Coronary artery calcification is a marker of coronary artery disease and it is associated with an adverse prognosis on dedicated cardiac imaging and on non-gated thoracic CT performed for non-cardiac indications, both with and without contrast. We recommend that coronary artery calcification is reported on all non-gated thoracic CT using a simple patient-based score (none, mild, moderate, severe). Furthermore, we recommend that reports include recommendations for subsequent management, namely the assessment of modifiable cardiovascular risk factors and, if the patient has chest pain, assessment as per standard guidelines. In most cases, this will not necessitate additional investigations. Incidental aortic valve calcification may also be identified on non-gated thoracic CT and should be reported, along with ancillary findings such as aortic root dilation. Calcification may occur in other parts of the heart including mitral valve/annulus, pericardium and myocardium, but in many cases these are an incidental finding without clinical significance.
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http://dx.doi.org/10.1259/bjr.20200894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7774698PMC
January 2021

FDG-PET/CT findings in COVID-19: a single centre retrospective radiological review.

BJR Case Rep 2020 Sep 26;6(3):20200091. Epub 2020 Jun 26.

Department of Radiology, Royal United Hospitals, Bath, UK.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the infectious disease COVID-19, was declared a global pandemic in March 2020. As radiology departments recommence FDG-PET/CT imaging, it is likely that both asymptomatic and specific symptomatic patients with COVID-19 infection will be imaged, particularly if the disease becomes endemic in the UK. We review the clinical scenarios where FDG-PET/CT could be performed in COVID-19 positive patients. Our local protocol for safely scanning known COVID-19 positive patients is described, highlighting considerations for other departments. We present the findings from a series of known COVID-19 positive patients and two further asymptomatic cases evaluated withFDG-PET/CT. Classic, indeterminate, normal and non-COVID-19 manifestations on both the FDG-PETand low dose CT component are described as an aid for radiologists and nuclear medicine physicians when reporting FDG PET/CT.
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http://dx.doi.org/10.1259/bjrcr.20200091DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7465739PMC
September 2020

COVID-19 in older people: a rapid clinical review.

Age Ageing 2020 07;49(4):501-515

Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK.

Introduction: the COVID-19 pandemic poses a high risk to older people. The aim of this article is to provide a rapid overview of the COVID-19 literature, with a specific focus on older adults. We frame our findings within an overview of the disease and have also evaluated the inclusion of older people within forthcoming clinical trials.

Methods: we searched PubMed and bioRxiv/medRxiv to identify English language papers describing the testing, treatment and prognosis of COVID-19. PubMed and bioRxiv/medRxiv searches took place on 20 and 24 March 2020, respectively.

Results: screening of over 1,100 peer-reviewed and pre-print papers yielded n = 22 on COVID-19 testing, n = 15 on treatment and n = 13 on prognosis. Viral polymerase chain reaction (PCR) and serology are the mainstays of testing, but a positive diagnosis may be increasingly supported by radiological findings. The current evidence for the effectiveness of antiviral, corticosteroid and immunotherapies is inconclusive, although trial data are largely based on younger people. In addition to age, male gender and comorbidities, specific laboratory and radiology findings are important prognostic factors. Evidence suggests that social distancing policies could have important negative consequences, particularly if in place for an extended period.

Conclusion: given the established association between increasing age and poor prognosis in COVID-19, we anticipate that this rapid review of the current and emergent evidence might form a basis on which future work can be established. Exclusion of older people, particularly those with comorbidities, from clinical trials is well recognised and is potentially being perpetuated in the field of current COVID-19 research.
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http://dx.doi.org/10.1093/ageing/afaa093DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7239238PMC
July 2020

Retrograde blood flow in the internal jugular veins of humans with hypertension may have implications for cerebral arterial blood flow.

Eur Radiol 2020 Jul 10;30(7):3890-3899. Epub 2020 Mar 10.

BHI CardioNomics Research Group, Clinical Research and Imaging Centre-Bristol, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, BS8 1TD, UK.

Objectives: To use multi-parametric magnetic resonance imaging (MRI) to test the hypothesis that hypertensives would have higher retrograde venous blood flow (RVBF) in the internal jugular veins (IJV) vs. normotensives, and that this would inversely correlate with arterial inflow and gray matter, white matter, and cerebrospinal fluid volumes.

Methods: Following local institutional review board approval and written consent, a prospective observational 3-T MRI study of 42 hypertensive patients (53 ± 2 years, BMI 28.2 ± 0.6 kg/m, ambulatory daytime systolic BP 148 ± 2 mmHg, ambulatory daytime diastolic BP 101 ± 2 mmHg) and 35 normotensive patients (48 ± 2 years, BMI 25.2 ± 0.8 kg/m, ambulatory daytime systolic BP 119 ± 3 mmHg, ambulatory daytime diastolic BP 90 ± 2 mmHg) was performed. Phase contrast imaging calculated percentage retrograde venous blood flow (%RVBF), brain segmentation estimated regional brain volumes from 3D T1-weighted images, and pseudo-continuous arterial spin labeling measured regional cerebral blood perfusion. Statistical analysis included two-sample equal variance Student's T tests, two-way analysis of variance with Tukey's post hoc correction, and permutation-based two-group general linear modeling (p < 0.05).

Results: In the left IJV, %RVBF was higher in hypertensives (6.1 ± 1.5%) vs. normotensives (1.1 ± 0.3%, p = 0.003). In hypertensives, there was an inverse relationship of %RVBF (permutation-based general linear modeling) to cerebral blood flow in several brain regions, including the left occipital pole and the cerebellar vermis (p < 0.01). Percentage retrograde flow in the left IJV correlated inversely with the total matter volume (gray plus white matter volume) in hypertensives (r = - 0.49, p = 0.004).

Conclusion: RVBF in the left IJV is greater in hypertensives vs. normotensives and is linked to regional hypoperfusion and brain total matter volume.

Key Points: • Hypertensive humans have higher retrograde cerebral venous blood flow, associated with regional brain hypoperfusion and lower tissue volume, compared with controls. • Cerebral retrograde venous blood flow may add further stress to already hypoperfused tissue in hypertensive patients. • The amount of retrograde venous blood flow in hypertensive patients may predict which patients might be at higher risk of developing cerebral pathologies.
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http://dx.doi.org/10.1007/s00330-020-06752-6DOI Listing
July 2020

Cross my heart: A rare case of anomalous coronary artery anatomy.

J Cardiovasc Comput Tomogr 2020 Nov - Dec;14(6):e145-e146. Epub 2019 Oct 31.

Department of Radiology, Royal United Hospitals Bath NHS Foundation Trust, Combe Park, Avon, Bath, BA1 3NG, United Kingdom. Electronic address:

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http://dx.doi.org/10.1016/j.jcct.2019.10.005DOI Listing
February 2021

Repaired coarctation of the aorta, persistent arterial hypertension and the selfish brain.

J Cardiovasc Magn Reson 2019 11 7;21(1):68. Epub 2019 Nov 7.

School of Physiology, Pharmacology & Neuroscience, Faculty of Biomedical Science, University of Bristol, Bristol, UK.

Background: It has been estimated that 20-30% of repaired aortic coarctation (CoA) patients develop hypertension, with significant cardiovascular morbidity and mortality. Vertebral artery hypoplasia (VAH) with an incomplete posterior circle of Willis (ipCoW; VAH + ipCoW) is associated with increased cerebrovascular resistance before the onset of increased sympathetic nerve activity in borderline hypertensive humans, suggesting brainstem hypoperfusion may evoke hypertension to maintain cerebral blood flow: the "selfish brain" hypothesis. We now assess the "selfish brain" in hypertension post-CoA repair.

Methods: Time-of-flight cardiovascular magnetic resonance angiography from 127 repaired CoA patients (34 ± 14 years, 61% male, systolic blood pressure (SBP) 138 ± 19 mmHg, diastolic blood pressure (DBP) 76 ± 11 mmHg) was compared with 33 normotensive controls (42 ± 14 years, 48% male, SBP 124 ± 10 mmHg, DBP 76 ± 8 mmHg). VAH was defined as < 2 mm and ipCoW as hypoplasia of one or both posterior communicating arteries.

Results: VAH + ipCoW was more prevalent in repaired CoA than controls (odds ratio: 5.8 [1.6-20.8], p = 0.007), after controlling for age, sex and body mass index (BMI). VAH + ipCoW was an independent predictor of hypertension (odds ratio: 2.5 [1.2-5.2], p = 0.017), after controlling for age, gender and BMI. Repaired CoA subjects with VAH + ipCoW were more likely to have difficult to treat hypertension (odds ratio: 3.3 [1.01-10.7], p = 0.049). Neither age at time of CoA repair nor any specific repair type were significant predictors of VAH + ipCoW in univariate regression analysis.

Conclusions: VAH + ipCoW predicts arterial hypertension and difficult to treat hypertension in repaired CoA. It is unrelated to age at time of repair or repair type. CoA appears to be a marker of wider congenital cerebrovascular problems. Understanding the "selfish brain" in post-CoA repair may help guide management.

Journal Subject Codes: High Blood Pressure; Hypertension; Magnetic Resonance Imaging (MRI); Cardiovascular Surgery; Cerebrovascular Malformations.
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http://dx.doi.org/10.1186/s12968-019-0578-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6839237PMC
November 2019

Cerebral Blood Flow Response to Simulated Hypovolemia in Essential Hypertension: A Magnetic Resonance Imaging Study.

Hypertension 2019 12 28;74(6):1391-1398. Epub 2019 Oct 28.

From the Faculty of Life Sciences, School of Physiology, Pharmacology and Neuroscience (S.N., Z.H.A., J.B., A.K.N., J.P., E.C.H.), University of Bristol, United Kingdom.

Hypertension is associated with raised cerebral vascular resistance and cerebrovascular remodeling. It is currently unclear whether the cerebral circulation can maintain cerebral blood flow (CBF) during reductions in cardiac output (CO) in hypertensive patients thereby avoiding hypoperfusion of the brain. We hypothesized that hypertension would impair the ability to effectively regulate CBF during simulated hypovolemia. In the present study, 39 participants (13 normotensive, 13 controlled, and 13 uncontrolled hypertensives; mean age±SD, 55±10 years) underwent lower body negative pressure (LBNP) at -20, -40, and -50 mmHg to decrease central blood volume. Phase-contrast MR angiography was used to measure flow in the basilar and internal carotid arteries, as well as the ascending aorta. CBF and CO decreased during LBNP (<0.0001). Heart rate increased during LBNP, reaching significance at -50 mmHg (<0.0001). There was no change in mean arterial pressure during LBNP (=0.3). All participants showed similar reductions in CBF (=0.3, between groups) and CO (=0.7, between groups) during LBNP. There was no difference in resting CBF between the groups (=0.36). In summary, during reductions in CO induced by hypovolemic stress, mean arterial pressure is maintained but CBF declines indicating that CBF is dependent on CO in middle-aged normotensive and hypertensive volunteers. Hypertension is not associated with impairments in the CBF response to reduced CO.
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http://dx.doi.org/10.1161/HYPERTENSIONAHA.119.13229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069391PMC
December 2019

CT-guided Microcoil Pulmonary Nodule Localization prior to Video-assisted Thoracoscopic Surgery: Diagnostic Utility and Recurrence-Free Survival.

Radiology 2019 04 5;291(1):214-222. Epub 2019 Feb 5.

From the Divisions of Cardiothoracic Imaging (J.C.L.R., K.H., J.K., T.B.C., M.P., E.T.N.), Thoracic Surgery (A.F.P., T.K.W., S.K., M.C., K.Y.), and Thoracic Pathology (M.C.), Toronto General Hospital, University Health Network, 585 University Ave, Toronto, ON, Canada M5G 2N2; Postgraduate Medical Education, Department of Medical Imaging, University of Toronto, Toronto, Canada (J.C.L.R.); and Department of Radiology, Royal United Hospitals Bath NHS Foundation Trust, Combe Park, Bath, England, United Kingdom, BA1 3NG (J.C.L.R.).

Background CT-guided microcoil localization has been shown to reduce the need for thoracotomy or video-assisted thoracoscopic surgery (VATS) anatomic resection. However, only short-term follow-up after CT-guided microcoil localization and lung resection has been previously reported. Purpose To assess the diagnostic utility and recurrence-free survival over a minimum of 2 years following CT-guided microcoil localization and VATS. Materials and Methods Among 1950 VATS procedures performed in a single tertiary institution from October 2008 through April 2016, 124 consecutive patients with CT-guided microcoil localization were retrospectively evaluated. Patient demographics, nodule characteristics, and histopathologic findings were recorded. The primary end point was recurrence-free survival after 2 or more years of CT surveillance. Statistical analysis included Kaplan-Meier survival curves and Cox regression. Results In 124 patients (men, 35%; mean age, 65 years ± 12) with a nodule found at CT, microcoil localization and VATS resection were performed for a total of 126 nodules (mean size, 13 mm ± 6; mean distance to pleura, 20 mm ± 9). On presurgical CT evaluation, 42% (53 of 126) of nodules were solid, 33% (41 of 126) were ground glass, and 24% (30 of 126) were subsolid. VATS excisional biopsy altered cytopathologic diagnosis in 21% (five of 24) of patients with prior diagnostic premicrocoil CT-guided biopsy. At histopathologic examination, 17% (21 of 126) of the nodules were adenocarcinoma in situ, 17% (22 of 126) were minimally invasive adenocarcinoma, 30% (38 of 126) were invasive lung primary tumors, and 22% (28 of 126) were metastases. Among the 72 patients with malignancy at histopathologic examination and at least 2 years of CT surveillance, local recurrence occurred in 7% (five of 72), intrathoracic recurrence in 22% (16 of 72), and extrathoracic recurrence in 18% (13 of 72) after 2 or more years of CT surveillance. There was no recurrence for adenocarcinoma in situ, minimally invasive adenocarcinoma, or invasive lung tumors measuring less than 1 cm. After multivariable adjustment, nodule location at a distance greater than 10 mm from the pleura was an independent predictor of time to recurrence (hazard ratio, 2.9 [95% confidence interval: 1.1, 7.4]; P = .03). Conclusion CT-guided microcoil localization and video-assisted thoracoscopic surgical resection alter clinical management and were associated with excellent recurrence-free survival for superficial premalignant, minimally invasive, and small invasive lung tumors. © RSNA, 2019 Online supplemental material is available for this article.
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http://dx.doi.org/10.1148/radiol.2019181674DOI Listing
April 2019

Left ventricular extracellular volume fraction and atrioventricular interaction in hypertension.

Eur Radiol 2019 Mar 19;29(3):1574-1585. Epub 2018 Sep 19.

Department of Radiology, Bristol Royal Infirmary, University Bristol NHS Foundation Trust, Bristol, UK.

Objectives: Left atrial enlargement (LAE) predicts cardiovascular morbidity and mortality. Impaired LA function also confers poor prognosis. This study aimed to determine whether left ventricular (LV) interstitial fibrosis is associated with LAE and LA impairment in systemic hypertension.

Methods: Following informed written consent, a prospective observational study of 86 hypertensive patients (49 ± 15 years, 53% male, office SBP 168 ± 30 mmHg, office DBP 97 ± 4 mmHg) and 20 normotensive controls (48 ± 13 years, 55% male, office SBP 130 ± 13 mmHg, office DBP 80 ± 11 mmHg) at 1.5-T cardiovascular magnetic resonance was conducted. Extracellular volume fraction (ECV) was calculated by T1-mapping. LA volume (LAV) was measured with biplane area-length method. LA reservoir, conduit and pump function were calculated with the phasic volumetric method.

Results: Indexed LAV correlated with indexed LV mass (R = 0.376, p < 0.0001) and ECV (R = 0.359, p = 0.001). However, ECV was the strongest significant predictor of LAE in multivariate regression analysis (odds ratio [95th confidence interval] 1.24 [1.04-1.48], p = 0.017). Indexed myocardial interstitial volume was associated with significant reductions in LA reservoir (R = -0.437, p < 0.0001) and conduit (R = -0.316, p = 0.003) but not pump (R = -0.167, p = 0.125) function. Multiple linear regression, correcting for age, gender, BMI, BP and diabetes, showed an independent decrease of 3.5% LA total emptying fraction for each 10 ml/m increase in myocardial interstitial volume (standard β coefficient -3.54, p = 0.002).

Conclusions: LV extracellular expansion is associated with LAE and impaired LA reservoir and conduit function. Future studies should identify if targeting diffuse LV fibrosis is beneficial in reverse remodelling of LA structural and functional pathological abnormalities in hypertension.

Key Points: • Left atrial enlargement (LAE) and impairment are markers of adverse prognosis in systemic hypertension but their pathophysiology is poorly understood. • Left ventricular extracellular volume fraction was the strongest independent multivariate predictor of LAE and was associated with impaired left atrial reservoir and conduit function. • LV interstitial expansion may play a central role in the pathophysiology of adverse atrioventricular interaction in systemic hypertension.
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http://dx.doi.org/10.1007/s00330-018-5700-zDOI Listing
March 2019

Noctural dipping status and left ventricular hypertrophy: A cardiac magnetic resonance imaging study.

J Clin Hypertens (Greenwich) 2018 04 8;20(4):784-793. Epub 2018 Mar 8.

NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.

We investigate the impact of dipper status on cardiac structure with cardiovascular magnetic resonance (CMR). Ambulatory blood pressure monitoring and 1.5T CMR were performed in 99 tertiary hypertension clinic patients. Subgroup analysis by extreme dipper (n = 9), dipper (n = 39), non-dipper (n = 35) and reverse dipper (n = 16) status was performed, matched in age, gender and BMI. Left ventricular (LV) mass was significantly higher for extreme dippers than dippers after correction for covariates (100 ± 6 g/m vs 79 ± 3 g/m , P = .004). Amongst extreme dippers and dippers (n = 48), indexed LV mass correlated positively with the extent of nocturnal blood pressure dipping (R = .403, P = .005). On post-hoc ANCOVA, the percentage of nocturnal dip had significant effect on indexed LV mass (P = .008), but overall SBP did not (P = .348). In the tertiary setting, we found a larger nocturnal BP drop was associated with more LV hypertrophy. If confirmed in larger studies, this may have implications on nocturnal dosing of anti-hypertensive medications.
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http://dx.doi.org/10.1111/jch.13235DOI Listing
April 2018

Cardiovascular Manifestations and Complications of Loeys-Dietz Syndrome: CT and MR Imaging Findings.

Radiographics 2018 Jan-Feb;38(1):275-286

From the Department of Clinical Radiology, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin St, Bristol BS2 8HW, England (W.W.L., K.S.M., J.C.L.R., S.M.L., H.E.B., N.E.M., M.C.K.H.); Department of Vascular Surgery, North Bristol NHS Trust, Bristol, England (M.J.B.); and Department of Cardiology (Congenital Heart Disease), Bristol Royal Hospital for Children/Bristol Heart Institute, Bristol, England (G.S.).

Loeys-Dietz syndrome (LDS) is a recently described genetic connective tissue disorder with a wide spectrum of multisystem involvement. LDS is characterized by rapidly progressive aortic and peripheral arterial aneurysmal disease. LDS and the other inherited aortopathies such as Marfan syndrome have overlapping phenotypic features. However, LDS is characterized by a more aggressive vascular course; patient morbidity and mortality occur at an early age, with complications developing at relatively smaller aortic dimensions. In addition, there is more diffuse arterial involvement in LDS, with a large proportion of patients developing aneurysms of the iliac, mesenteric, and intracranial arteries. Early diagnosis and careful follow-up are essential for ensuring timely intervention in patients with arterial disease. Cross-sectional angiography has an important role in the baseline assessment, follow-up, and evaluation of acute complications of LDS, the thresholds and considerations of which differ from those of other inherited aortopathies. In this article, LDS is compared with other genetic vascular connective tissue disorders. In addition, the genetic, histopathologic, and cardiovascular manifestations of this disease process are reviewed, with a focus on computed tomographic and magnetic resonance imaging findings. Online DICOM image stacks and supplemental material are available for this article. RSNA, 2018.
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http://dx.doi.org/10.1148/rg.2018170120DOI Listing
August 2018

The In Vivo Morphology of Post-Infarct Ventricular Septal Defect and the Implications for Closure.

JACC Cardiovasc Interv 2017 06;10(12):1233-1243

Department of Cardiology, Bristol Royal Infirmary, University Hospitals Bristol, Bristol, United Kingdom.

Objectives: The aim of this study was to define the dynamic in vivo morphology of post-infarct ventricular septal defect (PIVSD), which has not been previously described in living patients.

Background: PIVSD is a devastating complication of acute myocardial infarction.

Methods: The anatomic features of PIVSD, as demonstrated by computed tomography or magnetic resonance imaging, were retrospectively reviewed.

Results: Thirty-two PIVSDs were assessed, 16 left coronary artery and 16 right coronary artery PIVSDs. PIVSDs were large (mean maximum dimension 26.5 ± 11.5 mm, mean area 5.2 ± 4.2 cm) and oval (mean eccentricity index 1.7 ± 0.5), with thin margins (diastolic mean thickness 5 mm from the edge of the PIVSD 6.4 ± 3.0mm), and only 22% of PIVSDs were entirely confined to the septum. The defects could be larger in diastole or systole. The stem of the largest available Amplatzer occluder stem (St. Jude Medical, St. Paul, Minnesota) filled only 50% of defects. Patients with small defects may survive without closure. Without closure, those with large defects die. If accepted for closure, PIVSD size and coronary territory did not predict survival >1 year (overall 60%).

Conclusions: This is the first detailed anatomic description of PIVSD in living patients. Defects may be larger in systole or diastole, meaning that single-phase measurement is unsuitable. Its complex nature means that the most commonly available occluder device is frequently unsuitable. Successful closure leads to prolonged survival and should be attempted where possible. This study may lead to improved patient selection, closure techniques, and device design.
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http://dx.doi.org/10.1016/j.jcin.2017.03.042DOI Listing
June 2017

Left ventricular thrombus or pseudothrombus? A rare cardiac CT artifact.

Eur Heart J Cardiovasc Imaging 2017 10;18(10):1186

Department of Radiology, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol, BS2 8HW, UK.

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http://dx.doi.org/10.1093/ehjci/jex149DOI Listing
October 2017

An unusual cause of 'dextrocardia'.

Eur Heart J Cardiovasc Imaging 2017 Apr;18(4):488

NIHR Bristol Cardiovascular Biomedical Research Unit, Department of Cardiovascular Magnetic Resonance, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol, BS2 8HW, UK.

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http://dx.doi.org/10.1093/ehjci/jew319DOI Listing
April 2017

The Relationship Between Left Ventricular Wall Thickness, Myocardial Shortening, and Ejection Fraction in Hypertensive Heart Disease: Insights From Cardiac Magnetic Resonance Imaging.

J Clin Hypertens (Greenwich) 2016 11 17;18(11):1119-1127. Epub 2016 Jun 17.

Medical School, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK.

Hypertensive heart disease is often associated with a preserved left ventricular ejection fraction despite impaired myocardial shortening. The authors investigated this paradox in 55 hypertensive patients (52±13 years, 58% male) and 32 age- and sex-matched normotensive control patients (49±11 years, 56% male) who underwent cardiac magnetic resonance imaging at 1.5T. Long-axis shortening (R=0.62), midwall fractional shortening (R=0.68), and radial strain (R=0.48) all decreased (P<.001) as end-diastolic wall thickness increased. However, absolute wall thickening (defined as end-systolic minus end-diastolic wall thickness) was maintained, despite the reduced myocardial shortening. Absolute wall thickening correlated with ejection fraction (R=0.70, P<.0001). In multiple linear regression analysis, increasing wall thickness by 1 mm independently increased ejection fraction by 3.43 percentage points (adjusted β-coefficient: 3.43 [2.60-4.26], P<.0001). Increasing end-diastolic wall thickness augments ejection fraction through preservation of absolute wall thickening. Left ventricular ejection fraction should not be used in patients with hypertensive heart disease without correction for degree of hypertrophy.
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http://dx.doi.org/10.1111/jch.12849DOI Listing
November 2016

Comprehensive First-Line Magnetic Resonance Imaging in Hypertension: Experience From a Single-Center Tertiary Referral Clinic.

J Clin Hypertens (Greenwich) 2017 01 19;19(1):13-22. Epub 2016 Oct 19.

CardioNomics Research Group, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, University of Bristol, Bristol, UK.

European guidelines recommend that patients with hypertension be assessed for asymptomatic organ damage and secondary causes. The authors propose that a single magnetic resonance imaging (MRI) scan can provide comprehensive first-line imaging of patients assessed via a specialist hypertension clinic. A total of 200 patients (56% male, aged 51±15 years, office BP 168±30/96±16 mm Hg) underwent MRI of the heart, kidneys, renal arteries, adrenals and aorta. Comparisons were made with other imaging modalities where available. A total of 61% had left ventricular hypertrophy (LVH), 14% had reduced ejection fraction, and 15 patients had myocardial infarcts. Echocardiography overdiagnosed LVH in 15% of patients and missed LVH in 14%. Secondary causes were identified in 14.5% of patients: 12 adrenal masses, 10 renal artery stenoses, seven thyroid abnormalities, one aortic coarctation, one enlarged pituitary gland, one polycystic kidney disease, and one renal coloboma syndrome. This comprehensive MRI protocol is an effective method of screening for asymptomatic organ damage and secondary causes of hypertension.
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http://dx.doi.org/10.1111/jch.12920DOI Listing
January 2017

Is High Blood Pressure Self-Protection for the Brain?

Circ Res 2016 Dec 26;119(12):e140-e151. Epub 2016 Sep 26.

From the Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, United Kingdom (E.A.H.W., R.G.W.); CardioNomics Research Group, Clinical Research and Imaging Centre (J.C.L.R., A.E.B., S.N., L.E.K.R., N.E.M., A.K.N., J.F.R.P., E.C.H.) and School of Physiology, Pharmacology, and Neuroscience, Biomedical Sciences (J.C.L.R., S.N., L.E.K.R., Z.A., J.F.R.P., E.C.H.), University of Bristol, United Kingdom; University Hospitals Bristol NHS Foundation Trust, United Kingdom (S.N., L.E.K.R., Z.A., J.F.R.P., E.C.H.); Department of Radiology, University of Calgary, Canada (A.D.H.); and CAIR Program, Alberta Children's Hospital Research Institute, University of Calgary, Hotchkiss Brain Institute, Canada (A.D.H.).

Rationale: Data from animal models of hypertension indicate that high blood pressure may develop as a vital mechanism to maintain adequate blood flow to the brain. We propose that congenital vascular variants of the posterior cerebral circulation and cerebral hypoperfusion could partially explain the pathogenesis of essential hypertension, which remains enigmatic in 95% of patients.

Objective: To evaluate the role of the cerebral circulation in the pathophysiology of hypertension.

Methods And Results: We completed a series of retrospective and mechanistic case-control magnetic resonance imaging and physiological studies in normotensive and hypertensive humans (n=259). Interestingly, in humans with hypertension, we report a higher prevalence of congenital cerebrovascular variants; vertebral artery hypoplasia, and an incomplete posterior circle of Willis, which were coupled with increased cerebral vascular resistance, reduced cerebral blood flow, and a higher incidence of lacunar type infarcts. Causally, cerebral vascular resistance was elevated before the onset of hypertension and elevated sympathetic nerve activity (n=126). Interestingly, untreated hypertensive patients (n=20) had a cerebral blood flow similar to age-matched controls (n=28). However, participants receiving antihypertensive therapy (with blood pressure controlled below target levels) had reduced cerebral perfusion (n=19). Finally, elevated cerebral vascular resistance was a predictor of hypertension, suggesting that it may be a novel prognostic or diagnostic marker (n=126).

Conclusions: Our data indicate that congenital cerebrovascular variants in the posterior circulation and the associated cerebral hypoperfusion may be a factor in triggering hypertension. Therefore, lowering blood pressure may worsen cerebral perfusion in susceptible individuals.
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http://dx.doi.org/10.1161/CIRCRESAHA.116.309493DOI Listing
December 2016

Characteristics and trends in publication of scientific papers presented at the European Congress of Radiology: a comparison between 2000 and 2010.

Insights Imaging 2016 Oct 2;7(5):755-62. Epub 2016 Aug 2.

Southmead Hospital, Bristol, UK.

Objective: To determine journal publication rates of scientific papers presented orally at the European Congress of Radiology (ECR) 2010, with comparison of country data to ECR 2000.

Methods: All oral presentations from ECR 2010 were evaluated for publication between 2010 and 2014 using the MEDLINE database. Countries, collaborations, subspecialties, modalities and study design were ranked by publication percentage. Chi-square tests were used to compare publication percentages for each category of variables. Hazard ratios (HR) were calculated for each country relative to the host nation, Austria. ECR 2010 country statistics were compared with analogous data from ECR 2000.

Results: In total, 360/840 abstracts were subsequently published (43 %). The author's country of origin (p = 0.02), subspecialty (p = 0.02) and study design (p = 0.001) were significantly associated with subsequent publication. Switzerland, the Netherlands, France and Germany were among the top six countries by publication percentage in 2000 and 2010. In 2010, Switzerland had the highest publication rate (62 %) and HR in comparison to Austria (HR 2.62 [1.31-5.25], p = 0.01). Three Asian nations increased relative publication rates over the 10-year period.

Conclusion: Several European nations consistently convert relatively high percentages of oral abstracts at ECR into publications, and the influence of Asian countries is increasing.

Main Messages: • Certain European nations consistently publish high percentages of orally presented abstracts at ECR. • The influence of several Asian countries on ECR is increasing. • Country, subspecialty and study design are significantly associated with journal publication. • Authors collaborating internationally have the highest publication rates and mean impact factors. • Among all modalities, PET-CT, MRI and CT have the highest publication percentages.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5028340PMC
http://dx.doi.org/10.1007/s13244-016-0511-8DOI Listing
October 2016

Hypertensive heart disease versus hypertrophic cardiomyopathy: multi-parametric cardiovascular magnetic resonance discriminators when end-diastolic wall thickness ≥ 15 mm.

Eur Radiol 2017 Mar 1;27(3):1125-1135. Epub 2016 Jul 1.

NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol, BS2 8HW, UK.

Objectives: European guidelines state left ventricular (LV) end-diastolic wall thickness (EDWT) ≥15mm suggests hypertrophic cardiomyopathy (HCM), but distinguishing from hypertensive heart disease (HHD) is challenging. We identify cardiovascular magnetic resonance (CMR) predictors of HHD over HCM when EDWT ≥15mm.

Methods: 2481 consecutive clinical CMRs between 2014 and 2015 were reviewed. 464 segments from 29 HCM subjects with EDWT ≥15mm but without other cardiac abnormality, hypertension or renal impairment were analyzed. 432 segments from 27 HHD subjects with EDWT ≥15mm but without concomitant cardiac pathology were analyzed. Magnitude and location of maximal EDWT, presence of late gadolinium enhancement (LGE), LV asymmetry (>1.5-fold opposing segment) and systolic anterior motion of the mitral valve (SAM) were measured. Multivariate logistic regression was performed. Significance was defined as p<0.05.

Results: HHD and HCM cohorts were age-/gender-matched. HHD had significantly increased indexed LV mass (110±27g/m vs. 91±31g/m, p=0.016) but no difference in site or magnitude of maximal EDWT. Mid-wall LGE was significantly more prevalent in HCM. Elevated indexed LVM, mid-wall LGE and absence of SAM were significant multivariate predictors of HHD, but LV asymmetry was not.

Conclusions: Increased indexed LV mass, absence of mid-wall LGE and absence of SAM are better CMR discriminators of HHD from HCM than EDWT ≥15mm.

Key Points: • Hypertrophic cardiomyopathy (HCM) is often diagnosed with end-diastolic wall thickness ≥15mm. • Hypertensive heart disease (HHD) can be difficult to distinguish from HCM. • Retrospective case-control study showed that location and magnitude of EDWT are poor discriminators. • Increased left ventricular mass and midwall fibrosis are independent predictors of HHD. • Cardiovascular magnetic resonance parameters facilitate a better discrimination between HHD and HCM.
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http://dx.doi.org/10.1007/s00330-016-4468-2DOI Listing
March 2017

ECG strain pattern in hypertension is associated with myocardial cellular expansion and diffuse interstitial fibrosis: a multi-parametric cardiac magnetic resonance study.

Eur Heart J Cardiovasc Imaging 2017 Apr;18(4):441-450

NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.

Aims: In hypertension, the presence of left ventricular (LV) strain pattern on 12-lead electrocardiogram (ECG) carries adverse cardiovascular prognosis. The underlying mechanisms are poorly understood. We investigated whether hypertensive ECG strain is associated with myocardial interstitial fibrosis and impaired myocardial strain, assessed by multi-parametric cardiac magnetic resonance (CMR).

Methods And Results: A total of 100 hypertensive patients [50 ± 14 years, male: 58%, office systolic blood pressure (SBP): 170 ± 30 mmHg, office diastolic blood pressure (DBP): 97 ± 14 mmHg) underwent ECG and 1.5T CMR and were compared with 25 normotensive controls (46 ± 14 years, 60% male, SBP: 124 ± 8 mmHg, DBP: 76 ± 7 mmHg). Native T1 and extracellular volume fraction (ECV) were calculated with the modified look-locker inversion-recovery sequence. Myocardial strain values were estimated with voxel-tracking software. ECG strain (n = 20) was associated with significantly higher indexed LV mass (LVM) (119 ± 32 vs. 80 ± 17 g/m2, P < 0.05) and ECV (30 ± 4 vs. 27 ± 3%, P < 0.05) compared with hypertensive subjects without ECG strain (n = 80). ECG strain subjects had significantly impaired circumferential strain compared with hypertensive subjects without ECG strain and controls (-15.2 ± 4.7 vs. -17.0 ± 3.3 vs. -17.3 ± 2.4%, P < 0.05, respectively). In subgroup analysis, comparing ECG strain subjects to hypertensive subjects with elevated LVM but no ECG strain, a significantly higher ECV (30 ± 4 vs. 28 ± 3%, P < 0.05) was still observed. Indexed LVM was the only variable independently associated with ECG strain in multivariate logistic regression analysis [odds ratio (95th confidence interval): 1.07 (1.02-1.12), P < 0.05).

Conclusion: In hypertension, ECG strain is a marker of advanced LVH associated with increased interstitial fibrosis and associated with significant myocardial circumferential strain impairment.
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http://dx.doi.org/10.1093/ehjci/jew117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5837603PMC
April 2017

Comprehensive characterisation of hypertensive heart disease left ventricular phenotypes.

Heart 2016 10 3;102(20):1671-9. Epub 2016 Jun 3.

NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK Department of Cardiology, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.

Objective: Myocardial intracellular/extracellular structure and aortic function were assessed among hypertensive left ventricular (LV) phenotypes using cardiovascular magnetic resonance (CMR).

Methods: An observational study from consecutive tertiary hypertension clinic patients referred for CMR (1.5 T) was performed. Four LV phenotypes were defined: (1) normal with normal indexed LV mass (LVM) and LVM to volume ratio (M/V), (2) concentric remodelling with normal LVM but elevated M/V, (3) concentric LV hypertrophy (LVH) with elevated LVM but normal indexed end-diastolic volume (EDV) or (4) eccentric LVH with elevated LVM and EDV. Extracellular volume fraction was measured using T1-mapping. Circumferential strain was calculated by voxel-tracking. Aortic distensibility was derived from high-resolution aortic cines and contemporaneous blood pressure measurements.

Results: 88 hypertensive patients (49±14 years, 57% men, systolic blood pressure (SBP): 167±30 mm Hg, diastolic blood pressure (DBP): 96±14 mm Hg) were compared with 29 age-matched/sex-matched controls (47±14 years, 59% men, SBP: 128±12 mm Hg, DBP: 79±10 mm Hg). LVH resulted from increased myocardial cell volume (eccentric LVH: 78±19 mL/m(2) vs concentric LVH: 73±15 mL/m(2) vs concentric remodelling: 55±9 mL/m(2), p<0.05, respectively) and interstitial fibrosis (eccentric LVH: 33±10 mL/m(2) vs concentric LVH: 30±10 mL/m(2) vs concentricremodelling: 19±2 mL/m(2), p<0.05, respectively). LVH had worst circumferential impairment (eccentric LVH: -12.8±4.6% vs concentric LVH: -15.5±3.1% vs concentric remodelling: -17.1±3.2%, p<0.05, respectively). Concentric remodelling was associated with reduced aortic distensibility, but not with large intracellular/interstitial expansion or myocardial dysfunction versus controls.

Conclusions: Myocardial interstitial fibrosis varies across hypertensive LV phenotypes with functional consequences. Eccentric LVH has the most fibrosis and systolic impairment. Concentric remodelling is only associated with abnormal aortic function. Understanding these differences may help tailor future antihypertensive treatments.
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http://dx.doi.org/10.1136/heartjnl-2016-309576DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5099214PMC
October 2016

Extra-cardiac findings in cardiovascular magnetic resonance: what the imaging cardiologist needs to know.

J Cardiovasc Magn Reson 2016 05 9;18(1):26. Epub 2016 May 9.

Cardiovascular Magnetic Resonance Unit, NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University of Bristol, Bristol, UK.

Cardiovascular magnetic resonance (CMR) is an established non-invasive technique to comprehensively assess cardiovascular structure and function in a variety of acquired and inherited cardiac conditions. A significant amount of the neck, thorax and upper abdomen are imaged at the time of routine clinical CMR, particularly in the initial multi-slice axial and coronal images. The discovery of unsuspected disease at the time of imaging has ethical, financial and medico-legal implications. Extra-cardiac findings at the time of CMR are common, can be important and can change clinical management. Certain patient groups undergoing CMR are at particular risk of important extra-cardiac findings as several of the cardiovascular risk factors for atherosclerosis are also risk factors for malignancy. Furthermore, the presence of certain extra-cardiac findings may contribute to the interpretation of the primary cardiac pathology as some cardiac conditions have multi-systemic extra-cardiac involvement. The aim of this review is to give an overview of the type of extra-cardiac findings that may become apparent on CMR, subdivided by anatomical location. We focus on normal variant anatomy that may mimic disease, common incidental extra-cardiac findings and important imaging signs that help distinguish sinister pathology from benign disease. We also aim to provide a framework to the approach and potential further diagnostic work-up of incidental extra-cardiac findings discovered at the time of CMR. However, it is beyond the scope of this review to discuss and determine the clinical significance of extracardiac findings at CMR.
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http://dx.doi.org/10.1186/s12968-016-0246-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4860770PMC
May 2016
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