Successful valve-in-valve transcatheter intervention to treat severe stenosis of a 38-year-old tricuspid bioprosthesis

A 60-year-old man presented with breathlessness. Nearly four decades previously, he had required three operations for Staphylococcus aureus infective endocarditis of the tricuspid valve and had received a bioprosthetic valve. He had critical tricuspid bioprosthesis stenosis which was treated successfully by valve-in-valve transcatheter tricuspid valve replacement using a balloon-expandable transcatheter heart valve. One year after intervention, the patient is well with no tricuspid valve stenosis or regurgitation.

Prevalence, characteristics and clinical impact of work-related musculoskeletal pain in echocardiography

BACKGROUND

Work-related musculoskeletal pain (WRMSP) is increasingly recognised in cardiac ultrasound practice. WRMSP can impact workforce health, productivity and sustainability. We sought to investigate the prevalence, characteristics and clinical impact of WRMSP.

METHODS

Prospective electronic survey of 157 echocardiographers in 10 institutions. Data acquired on demographics, experience, working environment/pattern, WRMSP location, severity and pattern, the impact on professional, personal life and career.

RESULTS

129/157 (82%) echocardiographers completed the survey, of whom 109 (85%) reported WRMSP and 55 (43%) reported work taking longer due to WRMSP. 40/129 (31%) required time off work. 78/109 (60%) reported sleep disturbance with 26/78 (33%) of moderate or severe severity. 56/129 (45%) required medical evaluation of their WRMSP and 25/129 (19%) received a formal diagnosis of musculoskeletal injury. Those with 11+ years of experience were significantly more likely to receive a formal diagnosis of WRMSP (p = 0.002) and require medication (p = 0.006) compared to those with 10 years or less experience.

CONCLUSION

WRMSP is very common amongst echocardiographers, with a fifth having a related musculoskeletal injury. WRMSP has considerable on impact on personal, social and work-related activities. Strategies to reduce the burden of WRMSP are urgently required to ensure sustainability of the workforce and patient access to imaging.

Impact of gender, ethnicity and social deprivation on access to surgical or transcatheter aortic valve replacement in aortic stenosis: a retrospective database study in England

OBJECTIVE

To assess gender, ethnicity, and deprivation-based differences in provision of aortic valve replacement (AVR) in England for adults with aortic stenosis (AS).

METHODS

We retrospectively identified adults with AS from the English Hospital Episode Statistics (HES) between April 2016 and March 2019 and those who subsequently had an AVR. We separately used HES-linked Clinical Practice Research Datalink (CPRD) to identify people with AVR and evaluate the timeliness of their procedure (CPRD-AVR cohort). ORs for AVR in people with an AS diagnosis were estimated using multivariable logistic regression adjusted for age, region and comorbidity. AVR was considered timely if performed electively and without evidence of cardiac decompensation before AVR.

RESULTS

183 591 adults with AS were identified in HES; of these, 31 436 underwent AVR. The CPRD-AVR cohort comprised 10 069 adults. Women had lower odds of receiving AVR compared with men (OR 0.65; 95% CI 0.63 to 0.66); as did people of black (OR 0.70; 95% CI 0.60 to 0.82) or South Asian (OR 0.75; 95% CI 0.69 to 0.82) compared with people of white ethnicities. People in the most deprived areas were less likely to receive AVR than the least deprived areas (OR 0.8; 95% CI 0.75 to 0.86). Timely AVR occurred in 65% of those of white ethnicities compared with 55% of both those of black and South Asian ethnicities. 77% of the least deprived had a timely procedure compared with 58% of the most deprived; there was no gender difference.

CONCLUSIONS

In this large, national dataset, female gender, black or South Asian ethnicities and high deprivation were associated with significantly reduced odds of receiving AVR in England. A lower proportion of people of minority ethnicities or high deprivation had a timely procedure. Public health initiatives may be required to increase clinician and public awareness of unconscious biases towards minority and vulnerable populations to ensure timely AVR for everyone.

Impact of the admitting ward on care quality and outcomes in non-ST-segment elevation myocardial infarction: insights from a national registry

AIMS

Little is known about the association between the type of admission ward and quality of care and outcomes for non-ST-segment elevation myocardial infarction (NSTEMI).

METHODS AND RESULTS

We analysed data from 337 155 NSTEMI admissions between 2010 and 2017 in the UK Myocardial Ischaemia National Audit Project (MINAP) database. The cohort was dichotomised according to receipt of care either on a medical (n = 142,876) or cardiac ward, inclusive of acute cardiac wards and cardiac care unit (n = 194,279) on admission to hospital. Patients admitted to a cardiac ward were younger (median age 70 y vs. 75 y, P < 0.001), and less likely to be female (33% vs. 40%, P < 0.001). Independent factors associated with admission to a cardiac ward included ischaemic ECG changes (OR: 1.20, 95% CI: 1.18-1.23) and prior percutaneous coronary intervention (PCI) (OR: 1.19, 95% CI: 1.16-1.22). Patients admitted to a cardiac ward were more likely to receive optimal pharmacotherapy with statin (85% vs. 81%, P < 0.001) and dual antiplatelet therapy (DAPT) (91% vs. 88%, P < 0.001) on discharge, undergo invasive coronary angiography (78% vs. 59%, P < 0.001), and receive revascularisation in the form of PCI (52% vs. 36%, P < 0.001). Following multivariable logistic regression, the odds of inhospital all-cause mortality (OR: 0.75, 95% CI: 0.70-0.81) and major adverse cardiovascular events (MACE) (OR: 0.84, 95% CI: 0.78-0.91) were lower in patients admitted to a cardiac ward.

CONCLUSION

Patients with NSTEMI admitted to a cardiac ward on admission were more likely to receive guideline directed management and had better clinical outcomes.

Echocardiographic assessment of aortic stenosis: a practical guideline from the British Society of Echocardiography

The guideline provides a practical step-by-step guide in order to facilitate high-quality echocardiographic studies of patients with aortic stenosis. In addition, it addresses commonly encountered yet challenging clinical scenarios and covers the use of advanced echocardiographic techniques, including TOE and Dobutamine stress echocardiography in the assessment of aortic stenosis.

Analysis of conflicts of interest among authors and researchers of European clinical guidelines in cardiovascular medicine

OBJECTIVES

We aimed to assess the frequency and nature of financial conflicts of interest among both the guideline committee authors and the authors of research studies used to support the European Society of Cardiology (ESC) guidelines.

DESIGN

We evaluated the competing interests of the doctors that write five of the key ESC clinical practice guidelines (CPG): valvular heart disease (VHD), atrial fibrillation (AF), pericardial diseases (PD), heart failure (HF) and myocardial revascularisation (IHD). In addition, we examined the funding sources of studies cited in the recommendations that were related to pharmaceutical agents. If a study was sponsored by industry, the disclosures of all authors were reviewed to assess whether there was a financial conflict of interest with the study funder.

RESULTS

In total, there were 603 recommendations (PD 112, VHD 111, HF 169, IHD 97 and AF 114) across the five guidelines, of which, 271 (45% (PD 26, VHD 23, HF 72, IHD 84 and AF 66)) related to pharmaceutical agents. At least 80% of guideline committee authors, except for the PD guidelines, had a relevant financial conflict of interest, with the most frequent being a direct personal payment (68-82%). Industry support for studies varied across the guidelines from 5% (PD) to 65% (IHD). If a study was funded by industry, authors were frequently (55-90%) conflicted with the industry sponsor.

CONCLUSIONS

The majority of the doctors that write clinical guidelines have a relevant financial conflict of interest. In addition, industry sponsorship of studies is frequent, and authors are often conflicted with the study funder. We propose that physicians that write clinical guidelines should be free of such financial conflicts of interest to maintain scientific integrity and independence in the clinical guidelines.

Tropheryma whipplei endocarditis

Tropheryma whipplei is a bacterium that causes a rare infection called Whipple's disease and can cause devastating effects if left untreated. It is important to recognize that patients with this infection may present with atypical symptoms and are often apyrexial with normal inflammatory markers. Moreover, routine blood cultures often do not isolate these bacteria in conventional growth media. Therefore, it requires a high level of clinical suspicion to make this diagnosis. Here, we present two cases of Tropheryma whipplei aortic valve endocarditis, with atypical presentation and similar unusual but striking echocardiographic images.

Premature Structural Failure of Trifecta Bioprosthesis in Midterm Follow-up: A Single-Center Study

BACKGROUND

A cluster of aortic bioprosthetic valve failures, most of which were Trifecta bioprostheses, was observed in Southampton General Hospital, Southampton, United Kingdom. This study was performed to assess whether the cluster represents a significant failure of this valve model or whether there is a selection bias that can explain the failure of these valves.

METHODS

This retrospective study evaluated all bioprosthetic aortic valve replacement operations performed between 2011 and 2016 inclusive in our center. The study compared the performance of the Trifecta valve (Abbott, Abbott Park, IL) with that of Perimount (Edwards Lifesciences, Irvine, CA), Perimount Magna Ease, and Mitroflow (LivaNova, London, United Kingdom) bioprostheses. In addition, the study analyzed patient-related and valve-related risk factors for early failure in the failed valves.

RESULTS

A total of 2807 bioprosthetic aortic valve replacements were performed. Of these, 836 were Trifecta valves, 1031 were Perimount, 449 were Perimount Magna Ease, and 351 were Mitroflow valves. A total of 24 Trifecta valves had premature structural failure, a number significantly higher than seen with Perimount or Perimount Magna Ease (no failure, P < .001 and P < .005, respectively) valves and the Mitroflow valve (1 failure, P < .05). There was no difference in the incidence of endocarditis or death. At the time of valve failure, 17 (71%) of the failed Trifecta valves had moderate or severe regurgitation, and the average peak gradient was 61 ± 29 mm Hg. The median failed prosthetic size was 23 mm. One failed valve had severe patient-prosthesis mismatch. The mean time to failure was 4.5 ± 1.7 years.

CONCLUSIONS

The Trifecta bioprosthesis has an increased incidence of early structural valve failure, which is significantly higher than that of Perimount, Perimount Magna Ease, or Mitroflow. No patient-related or valve-related cause for the failure could be identified.

Machine learning detection of Atrial Fibrillation using wearable technology

BACKGROUND

Atrial Fibrillation is the most common arrhythmia worldwide with a global age adjusted prevalence of 0.5% in 2010. Anticoagulation treatment using warfarin or direct oral anticoagulants is effective in reducing the risk of AF-related stroke by approximately two-thirds and can provide a 10% reduction in overall mortality. There has been increased interest in detecting AF due to its increased incidence and the possibility to prevent AF-related strokes. Inexpensive consumer devices which measure the ECG may have the potential to accurately detect AF but do not generally incorporate diagnostic algorithms. Machine learning algorithms have the potential to improve patient outcomes particularly where diagnoses are made from large volumes or complex patterns of data such as in AF.

METHODS

We designed a novel AF detection algorithm using a de-correlated Lorenz plot of 60 consecutive RR intervals. In order to reduce the volume of data, the resulting images were compressed using a wavelet transformation (JPEG200 algorithm) and the compressed images were used as input data to a Support Vector Machine (SVM) classifier. We used the Massachusetts Institute of Technology (MIT)-Beth Israel Hospital (BIH) Atrial Fibrillation database and the MIT-BIH Arrhythmia database as training data and verified the algorithm performance using RR intervals collected using an inexpensive consumer heart rate monitor device (Polar-H7) in a case-control study.

RESULTS

The SVM algorithm yielded excellent discrimination in the training data with a sensitivity of 99.2% and a specificity of 99.5% for AF. In the validation data, the SVM algorithm correctly identified AF in 79/79 cases; sensitivity 100% (95% CI 95.4%-100%) and non-AF in 328/336 cases; specificity 97.6% (95% CI 95.4%-99.0%).

CONCLUSIONS

An inexpensive wearable heart rate monitor and machine learning algorithm can be used to detect AF with very high accuracy and has the capability to transmit ECG data which could be used to confirm AF. It could potentially be used for intermittent screening or continuously for prolonged periods to detect paroxysmal AF. Further work could lead to cost-effective and accurate estimation of AF burden and improved risk stratification in AF.

Frequency and impact of incidental findings on computed tomography during work-up for transcatheter aortic valve implantation: single centre experience and review of the literature

OBJECTIVE

To assess the frequency and impact of incidental findings (IF) on CT during work-up for transcatheter aortic valve intervention (TAVI).

METHODS

A consecutive cohort of patients referred for consideration of TAVI who underwent a CT scan between 2009 and 2018 were studied retrospectively. CT reports were reviewed for the presence of IFs and categorised based upon their clinical significance: (a) insignificant-findings that did not require specific treatment or follow-up; (b) intermediate-findings that did not impact on the decision-making process but required follow-up; (c) significant-findings that either required urgent investigation or meant that TAVI was clinically inappropriate.

RESULTS

A total of 652 patients were included, whose median age was 82 years. One or more insignificant IF was found in 95.6% of patients. Intermediate IFs were documented in 5.4%. 91 (14%) patients had at least one significant IF. These included possible malignancy in 67 (74%). The ultimate decision to offer aortic valve intervention was only changed by the presence of an IF in 3.5% of cases.

CONCLUSION

Clinically significant IFs are detected in more than 1 in 10 of patients undergoing CT as part of a TAVI work-up, although just over half of these patients still receive aortic valve intervention.

ADVANCES IN KNOWLEDGE

This study is the largest UK cohort, which, when combined with a review of existing literature, provides a clear picture of the frequency and clinical impact of IFs found at CT for TAVI assessment.

Screening for Atrial Fibrillation Using Economical and Accurate Technology (From the SAFETY Study)

The prevalence of atrial fibrillation (AF) is estimated at more than 3% in the adult population and there has been increased interest in screening for AF. In the SAFETY trial we chose to evaluate if inexpensive, wearable, consumer electrocardiography (ECG) sensing devices (Polar-H7 [PH7] and Firstbeat Bodyguard 2 [BG2]), could be used to detect AF accurately. We undertook a case-control study of 418 participants aged >65 (82 with AF and/or flutter at the study visit and 336 without) attending 3 general practice surgeries in Hampshire, UK for a single screening visit. The PH7 and BG2 devices were tested alongside 2 established AF detection devices (AliveCor and WatchBP) in random order and the diagnosis of AF was confirmed by 12-Lead ECG interpreted by a panel of cardiologists. The sensitivity (95% confidence interval [CI] range), specificity (95% CI range), and overall accuracy (95% CI range) of the 4 devices were: AliveCor: 87.8% (78.7% to 94.0%), 98.8% (97.0% to 99.7%), 96.7% (94.4% to 98.2%); WatchBP: 96.3% (89.7% to 99.2%), 93.5% (90.3% to 95.9%), 94.0% (91.3% to 96.1%): PH7: 96.3% (89.7% to 99.2%), 98.2% (96.2% to 99.3%), 97.9% (96.0% to 99.0%). BG2: 96.3% (89.7% to 99.2%), 98.5% (96.6% to 99.5%), 98.1% (96.3% to 99.2%). The PH7 and BG2 devices were highly reliable (the devices acquired sufficient data and obtained a diagnostic result in all but 1 participant on the first attempt). In conclusion, inexpensive, consumer heart rate monitoring devices (PH7 and BG2) can be used to detect AF accurately with sensitivity and specificity >95%. The consumer devices performed as well or better than WatchBP and AliveCor and have the capability to store or transmit ECG data which could be used to confirm AF.

Clinical and echocardiographic follow-up of patients following surgical heart valve repair or replacement: a tertiary centre experience

International best practice guidelines recommend lifelong follow-up of patients that have undergone valve repair or replacement surgery and provide recommendations on the utilization of echocardiography during follow-up. However, such follow-up regimes can vary significantly between different centres and sometimes within the same centre. We undertook this study to determine the patterns of clinical follow-up and use of transthoracic echocardiography (TTE) amongst cardiologists in a large UK tertiary centre. In this retrospective study, we identified patients that underwent heart valve repair or replacement surgery in 2008. We used local postal codes to identify patients within our hospital's follow-up catchment area. We determined the frequency of clinical follow-up and use of transthoracic echocardiography (TTE) during the 9-year follow-up period (2009-2016 inclusive). Of 552 patients that underwent heart valve surgery, 93 (17%) were eligible for local follow-up. Of these, the majority (61/93, 66%) were discharged after their 6-week post-operative check-up with no further follow-up. Of the remaining 32 patients, there was remarkable heterogeneity in follow-up regimes and use of TTE. This variation did not correlate with the prosthesis type. In summary, the frequency of clinical follow-up and use of echocardiography is highly variable in contemporary practice. Many patients are inappropriately discharged back to their family doctor with no plans for hospital follow-up. These data further support the creation of dedicated specialist heart valve clinics to optimize patient care, ensure rational use of TTE and optimize adherence with best practice guidelines.

Stress echocardiography in contemporary clinical cardiology: practical considerations and accreditation

Stress echocardiography is a widely utilised test in patients with known or suspected coronary artery disease (CAD), valvular heart disease and cardiomyopathies. Its advantages include the ubiquitous availability of echocardiography, lack of ionising radiation, choice of physiological or pharmacological stressors, good diagnostic accuracy and robust supporting evidence base. SE has evolved significantly as a technique over the past three decades and has benefitted considerably from improvements in overall image quality (superior resolution), machine technology (e.g. digital cine-loop acquisition and side-by-side image display) and development of second-generation ultrasound contrast agents that have improved reader confidence and diagnostic accuracy. The purpose of this article is to review the breadth of SE in contemporary clinical cardiology and discuss the recently launched British Society of Echocardiography (BSE) Stress Echocardiography accreditation scheme.

Lesson of the month 1: Obesity hypoventilation (Pickwickian) syndrome: a reversible cause of severe pulmonary hypertension

Obesity hypoventilation syndrome (OHS) is a condition in which an individual with a body mass index >30 kg/m2 develops daytime alveolar hypoventilation (defined as a resting PaCO2 >45 mmHg) that cannot be attributed to other pathologies. It is a condition with increasing prevalence and rising cost to healthcare systems worldwide. Right heart failure and pulmonary hypertension are well-known complications of this syndrome. Here, we present the case of a female patient with OHS who presented to our centre with severe pulmonary hypertension, which resolved with appropriate treatment. We also review this clinical condition and its diagnosis and management.

Use of the CHA2DS2VASc score to reduce utilisation of transoesophageal echocardiography prior to ablation for atrial fibrillation

Transoesophageal echocardiography (TOE) is frequently performed prior to atrial fibrillation (AF) ablation to exclude left atrial appendage (LAA) thrombus. However, patients undergoing AF ablation are usually anticoagulated, thus making the presence of thrombus unlikely in most cases. This study aimed to determine whether the CHA₂DS₂VASc scoring system can be used to identify patients that do not require TOE prior to AF ablation. In this single-centre retrospective study, local institutional and primary care databases and electronic patient records were searched to identify patients that had undergone TOE prior to AF ablation. Patient demographics, CHA₂DS₂VASc score, TOE findings and anticoagulation status were collected for analysis. Over a 7-year period (2008–2014), 332 patients (age 57 ± 10 years; 74% male) underwent TOE prior to proposed AF ablation. CHA₂DS₂VASc scores of 0, 1, 2 and >2 were found in 39, 34, 15 and 12% of patients, respectively. The prevalence of LAA thrombus was 0.6% (2 patients) and these 2 patients had risk scores of 2 and 4. No patients with a score of 0 or 1 had LAA thrombus. Patients that are classed as low risk by the CHA₂DS₂VASc score do not require a pre-ablation TOE to screen for LAA thrombus provided they are adequately anticoagulated. This would lead to a significant reduction in health care expenditures by reducing unnecessary TOE requests and thereby improve patient experience.

Differential Intensity Projection for Visualisation and Quantification of Plaque Neovascularisation in Contrast-Enhanced Ultrasound Images of Carotid Arteries

Studies have reported that intraplaque neovascularisation (IPN) is closely correlated with plaque vulnerability. In this study, a new image processing approach, differential intensity projection (DIP), was developed to visualise and quantify IPN in contrast-enhanced non-linear ultrasound image sequences of carotid arteries. DIP used the difference between the local temporal maximum and the local temporal average signals to identify bubbles against tissue non-linear artefact and noise. The total absolute and relative areas occupied by bubbles within each plaque were calculated to quantify IPN. In vitro measurements on a laboratory phantom were made, followed by in vivo measurements in which 24 contrast-enhanced non-linear ultrasound image sequences of carotid arteries from 48 patients were selected and motion corrected. The results using DIP were compared with those obtained by maximum intensity projection (MIP) and visual assessment. The results indicated that DIP can significantly reduce non-linear propagation tissue artefacts and is much more specific in detecting bubble signals than MIP, being able to reveal microbubble signals that are buried in tissue artefacts in the corresponding MIP image. A good correlation was found between microvascular area (MVA) (r = 0.83, p < 0.001)/microvascular density (r = 0.77, p < 0.001) obtained using DIP and the corresponding expert visual grades, comparing favourably to r = 0.26 and 0.23 obtained using MIP on the same data. In conclusion, the proposed method exhibits great potential in quantification of IPN in contrast-enhanced ultrasound images of carotid arteries.

Contrast-enhanced ultrasonography vs B-mode ultrasound for visualization of intima-media thickness and detection of plaques in human carotid arteries

BACKGROUND

Carotid intima-media thickness (IMT) and plaque are recognized markers of increased risk for cerebrovascular events. Accurate visualization of the IMT and plaques is dependent upon image quality. Ultrasound contrast agents improve image quality during echocardiography-this study assessed whether contrast-enhanced ultrasound (CEUS) improves carotid IMT visualization and plaque detection in an asymptomatic population.

METHODS & RESULTS

Individuals free from known cardiovascular disease, enrolled in a community study, underwent B-mode and CEUS carotid imaging. Each carotid artery was divided into 10 segments (far and near walls of the proximal, mid and distal segments of the common carotid artery, the carotid bulb, and internal carotid artery). Visualization of the IMT complex and plaque assessments was made during both B-mode and CEUS imaging for all enrolled subjects, a total of 175 individuals (mean age 65±9 years). Visualization of the IMT was significantly improved during CEUS compared with B-mode imaging, in both near and far walls of the carotid arteries (% IMT visualization during B-mode vs CEUS imaging: 61% vs 94% and 66% vs 95% for right and left carotid arteries, respectively, P<.001 for both). Additionally, a greater number of plaques were detected during CEUS imaging compared with B-mode imaging (367 plaques vs 350 plaques, P=.02).

CONCLUSION

Contrast-enhanced ultrasound improves visualization of the intima-media complex, in both near and far walls, of the common and internal carotid arteries and permits greater detection of carotid plaques. Further studies are required to determine whether there is incremental clinical and prognostic benefit related to superior plaque detection by CEUS.

A unique case of "double-orifice aortic valve"-comprehensive assessment by 2-, 3-dimensional, and color Doppler echocardiography

Transesophageal echocardiography (TEE) is a powerful imaging tool for the comprehensive assessment of valvular structure and function. TEE may be of added benefit when anatomy is difficult to delineate accurately by transthoracic echocardiography. In this article, we present 2-, 3-dimensional, and color Doppler TEE images from a male patient with aortic stenosis. A highly unusual and complex pattern of valvular calcification created a functionally "double-orifice" valve. Such an abnormality may have implications for the accuracy of continuous-wave Doppler echocardiography, which assumes a single orifice valve in native aortic valves.

Contrast enhancement of carotid adventitial vasa vasorum as a biomarker of radiation-induced atherosclerosis

PURPOSE

Abnormal proliferation of adventitial vasa vasorum (vv) occurs early at sites of atherosclerosis and is thought to be an early biomarker of vascular damage. Contrast-enhanced ultrasound (CEUS) can detect this process. Its usefulness in irradiated arteries as a measure of accelerated atherosclerosis is unknown. This study investigates contrast intensity in carotid adventitia as an early marker of radiation-induced damage in head and neck cancer (HNC) patients.

MATERIALS/METHODS

Patients with HNC treated with a wedged-pair and matched neck technique or hemi-neck radiotherapy (RT) (unirradiated side as control) at least 2years previously were included. Patients had been prescribed a dose of at least 50Gy to the neck. CEUS was performed on both carotid arteries and a region of interest was selected in the adventitia of the far wall of both left and right distal common carotid arteries. Novel quantification software was used to compare the average intensity per pixel between irradiated and unirradiated arteries.

RESULTS

48 patients (34 males) with median age of 59.2years (interquartile range (IQR) 49.2-64.2) were included. The mean maximum point dose to the irradiated artery was 61.2Gy (IQR 52.6-61.8) and 1.1Gy (IQR 1.0-1.8Gy) to the unirradiated side. The median interval from RT was 59.4months (IQR 41-88.7). There was a significant difference in the mean (SD) contrast intensity per pixel on the irradiated side (1.1 (0.4)) versus 0.96 (0.34) on the unirradiated side (p=0.01). After attenuation correction, the difference in mean contrast intensity per pixel was still significant (1.4 (0.58) versus 1.2 (0.47) (p=0.02). Previous surgery or chemotherapy had no effect on the difference in contrast intensity between the 2 sides of the neck. Mean intensity per pixel did not correlate to traditional risk prediction models (carotid intima-medial thickness, QSTROKE score).

CONCLUSIONS

Proliferation of vv is demonstrated by increased contrast intensity in irradiated carotid arteries. This may be a useful, independent biomarker of radiation-induced carotid atherosclerosis when used as a tool to quantify neovascularization.

Do traditional risk stratification models for cerebrovascular events apply in irradiated head and neck cancer patients?

BACKGROUND

Primary radical radiotherapy (RT) for head and neck cancer (HNC) often results in significant radiation dose to the carotid arteries.

AIM

We assessed whether HNC patients are at increased risk of a cerebrovascular event primarily due to RT or other risk factors for atherosclerosis by (i) risk-stratifying patients according to validated QRISK-2 and QSTROKE scores and (ii) comparing the prevalence of carotid artery stenosis (CAS) in irradiated and unirradiated carotid arteries.

DESIGN

HNC patients treated with an RT dose >50 Gy to one side of the neck ≥2 years previously were included.

METHODS

QRISK-2 (2014) and Q-STROKE (2014) scores were calculated. We compared the prevalence of CAS in segments of the common carotid artery on the irradiated and unirradiated sides of the neck.

RESULTS

Fifty patients (median age of 58 years (interquartile range (IQR) 50-62)) were included. The median QRISK-2 score was 10% (IQR 4.4-15%) and the median QSTROKE score was 3.4% (IQR 1.4-5.3%). For both scores, no patient was classified as high risk. Thirty-eight patients (76%) had CAS in one or both arteries. There was a significant difference in the number of irradiated arteries with stenosis (N = 37) compared with unirradiated arteries (N = 16) (P < 0.0001). There were more plaques on the irradiated artery compared with the unirradiated side - 64/87 (73.6%) versus 23/87 (26.4%), respectively (P < 0.001). 

CONCLUSIONS

Traditional vascular risk factors do not play a role in radiation-induced carotid atherosclerosis. Clinicians should be aware that traditional risk prediction models may under-estimate stroke risk in these patients.

Stress echocardiography in patients with morbid obesity

The incidence of significant obesity is rising across the globe. These patients often have a clustering of cardiovascular risk factors and are frequently referred for noninvasive cardiac imaging tests. Stress echocardiography (SE) is widely used for assessment of patients with known or suspected coronary artery disease (CAD), but its clinical utility in morbidly obese patients (in whom image quality may suffer due to body habitus) has been largely unknown. The recently published Stress Ultrasonography in Morbid Obesity (SUMO) study has shown that SE, when performed appropriately with ultrasound contrast agents (whether performed with physiological or pharmacological stress), has excellent feasibility and appropriately risk stratifies morbidly obese patients, including identification of patients who require revascularization. This article reviews the evidence supporting the use of echocardiographic techniques in morbidly obese patients for assessment of known or suspected CAD and briefly discusses other noninvasive modalities, including magnetic resonance and nuclear techniques, comparing and contrasting these techniques against SE.

Attenuation Correction and Normalisation for Quantification of Contrast Enhancement in Ultrasound Images of Carotid Arteries

An automated attenuation correction and normalisation algorithm was developed to improve the quantification of contrast enhancement in ultrasound images of carotid arteries. The algorithm first corrects attenuation artefact and normalises intensity within the contrast agent-filled lumen and then extends the correction and normalisation to regions beyond the lumen. The algorithm was first validated on phantoms consisting of contrast agent-filled vessels embedded in tissue-mimicking materials of known attenuation. It was subsequently applied to in vivo contrast-enhanced ultrasound (CEUS) images of human carotid arteries. Both in vitro and in vivo results indicated significant reduction in the shadowing artefact and improved homogeneity within the carotid lumens after the correction. The error in quantification of microbubble contrast enhancement caused by attenuation on phantoms was reduced from 55% to 5% on average. In conclusion, the proposed method exhibited great potential in reducing attenuation artefact and improving quantification in contrast-enhanced ultrasound of carotid arteries.

Arterial Stiffness as a Biomarker of Radiation-Induced Carotid Atherosclerosis

Arterial stiffness is thought to be a precursor to atherosclerosis. Conventional arterial stiffness parameters as potential biomarkers of radiation-induced damage were investigated. Patients with head and neck cancer treated with radiotherapy ≥2 years previously to one side of the neck were included. The unirradiated side was the internal control. Beta stiffness index (B) and elastic modulus (Ep) were used to assess arterial stiffness and were measured in proximal, mid, and distal common carotid artery (CCA) and compared with the corresponding unirradiated segments. Fifty patients (68% male; median age 58 years; interquartile range 50-62) were included. Mean ± standard deviation maximum doses to irradiated and unirradiated arteries were 53 ± 13 and 1.9 ± 3.7 Gy, respectively. Differences in B were not significant. Significant differences in Ep were demonstrated-proximal CCA: 1301 ± 1223 versus 801 ± 492 (P < .0001), mid CCA: 1064 ± 818 versus 935.5 ± 793 (P < .0001), and distal CCA: 1267 ± 1084 versus 775.3 ± 551.9 (P < .0001). Surgery had no impact on arterial stiffness. Arterial stiffness is increased in irradiated arteries, in keeping with radiation-induced damage. Prospective data may show an association between arterial stiffness and atherosclerosis in this setting.

Relative diagnostic, prognostic and economic value of stress echocardiography versus exercise electrocardiography as initial investigation for the detection of coronary artery disease in patients with new onset suspected angina

Objectives

We hypothesised that stress echocardiography (SE), may be superior to exercise ECG (ExECG), for predicting CAD and outcome, and cost-beneficial, when performed as initial investigation in newly suspected angina.

Methods

All patients seen in 2011, with suspected angina, no history of CAD, pre-test likelihood of CAD of > 10% and who underwent SE or ExECG as first line were identified retrospectively. Cost to diagnosis was calculated by adding the cost of all tests, up to and including coronary angiography (CA), on an intention-to-treat basis. Follow-up data on cardiac death and myocardial infarction (MI) were collected, 26 months after the presentation of the last study patient.

Results

A total of 456 patients underwent ExECG (224 (49%) negative, 93 (20%) positive, 139 (31%) inconclusive) and 241 underwent SE (200 (83%) negative, 35 (15%) positive, 6 (2%) inconclusive) as first line. In patients subsequently undergoing CA, CAD was present in 46% (37/80) of patients with positive ExECG vs. 72% (23/32) patients with positive SE (p = 0.01). Mean cost to diagnosis was £456 for the ExECG vs. £360 for the SE group (p = 0.002). Over a mean follow-up period of 31 ± 5 months, cardiac events were 2% each in negative SE vs. negative ExECG (p = 0.9).

Conclusions

SE is superior to ExECG for prediction of CAD and is cost-beneficial when used as initial test in patients with no history of CAD presenting with suspected angina.

Role of simultaneous carotid ultrasound in patients undergoing stress echocardiography for assessment of chest pain with no previous history of coronary artery disease

BACKGROUND

We prospectively explored prevalence of carotid disease (CD), its independent association with coronary artery disease (CAD) and outcome as well as potential impact on management, in patients undergoing stress echocardiography (SE) for new onset chest pain without known CAD.

METHODS

Accordingly, 591 consecutive patients referred for SE underwent carotid ultrasound. Carotid disease was defined as carotid intima-media thickness (C-IMT) >75th percentile for age and sex and/or presence of plaque.

RESULTS

Myocardial ischemia was demonstrated in only a minority (11%), but there was a high prevalence of CD (70%). Incidence of CD was similar in patients with and without ischemia (76% versus 69%, P = .26). Carotid data led to reclassification of Framingham risk score categories in 65% of patients as well as more than a third of negative SE patients potentially benefitting from primary prevention therapy. Of the 83 patients undergoing coronary arteriography, 59 (71%) demonstrated coronary atherosclerosis (any atheroma) and 33 (40%) CAD. Positive predictive value of SE for CAD was 56%, but presence of carotid plaque improved it to 70%. Although both CD and plaque showed association with CAD and revascularization, after adjustment for conventional risk factors, only carotid plaque maintained significant association (P = .024 and P = .023, respectively).

CONCLUSIONS

There is significantly higher prevalence of CD compared with myocardial ischemia in patients undergoing SE and carotid ultrasound for suspected CAD. This can lead to significant Framingham risk score reclassification with important primary prevention implications. Carotid plaque is superior to clinical assessment for the prediction of CAD and improves positive predictive value of SE for CAD in these patients.

The feasibility and clinical utility of myocardial contrast echocardiography in clinical practice: results from the incorporation of myocardial perfusion assessment into clinical testing with stress echocardiography study

BACKGROUND

This prospective study investigated whether the incorporation of myocardial contrast echocardiography (MCE) into a clinical stress echocardiography service reproduces the benefits of assessing myocardial perfusion proved previously in research studies.

METHODS

MCE was performed during physiologic and pharmacologic clinical stress echocardiographic studies, and the value of myocardial perfusion to the reporting echocardiologists was categorized as of benefit (subclassified as incremental benefit over wall motion [WM] or greater confidence with WM) or of no added benefit. The presence and extent of inducible ischemia by WM and myocardial perfusion were documented and correlated with angiographic results in patients who underwent cardiac catheterization.

RESULTS

In total, 220 patients underwent simultaneous MCE during stress echocardiography by eight different operators. Overall, MCE was of benefit in 193 patients (88%), providing incremental benefit over WM in 25% and greater confidence with WM evaluation in 62%. MCE provided no added benefit in 27 patients (12%). MCE detected significantly more cases of ischemia than WM in the left anterior descending coronary artery territory (65% vs 53%, P = .02) and detected a greater ischemic burden than WM on a per patient basis (median, 5 [interquartile range, 3-8] vs 4 [interquartile range, 2-7] segments; P < .001) and across all coronary territories. MCE correctly identified a greater proportion of patients with multivessel disease than WM (76% vs 56%, P = .02) and a greater ischemic burden in patients with multivessel disease (median, 7 [interquartile range, 4-9] vs 5 [interquartile range, 1-8] segments; P < .001).

CONCLUSIONS

This prospective study is the first to demonstrate that the excellent feasibility and diagnostic utility of MCE, which have been documented in the research arena, are reproducible in the clinical arena.