The Potential Role of Cardiac CT in the Evaluation of Patients With Known or Suspected Cardiomyopathy: From Traditional Indications to Novel Clinical Applications

After 15 years from its advent in the clinical field, coronary computed tomography (CCTA) is now widely considered as the best first-step test in patients with low-to-moderate pre-test probability of coronary artery disease. Technological innovation was of pivotal importance for the extensive clinical and scientific interest in CCTA. Recently, the advent of last generation wide-coverage CT scans paved the way for new clinical applications of this technique beyond coronary arteries anatomy evaluation. More precisely, both biventricular volume and systolic function quantification and myocardial fibrosis identification appeared to be feasible with last generation CT. In the present review we would focus on potential applications of cardiac computed tomography (CCT), beyond CCTA, for a comprehensive assessment patients with newly diagnosed cardiomyopathy, from technical requirements to novel clinical applications.

Association between right ventricular strain and outcomes in patients with dilated cardiomyopathy

OBJECTIVE

To explore the association between three-dimensional (3D) cardiac magnetic resonance (CMR) feature tracking (FT) right ventricular peak global longitudinal strain (RVpGLS) and major adverse cardiovascular events (MACEs) in patients with stage C or D heart failure (HF) with non-ischaemic dilated cardiomyopathy (NIDCM) but without atrial fibrillation (AF).

METHODS

Patients with dilated cardiomyopathy were enrolled in this prospective cohort study. Comprehensive clinical and biochemical analysis and CMR imaging were performed. All patients were followed up for MACEs.

RESULTS

A total of 192 patients (age 53±14 years) were eligible for this study. A combination of cardiovascular death and cardiac transplantation occurred in 18 subjects during the median follow-up of 567 (311, 920) days. Brain natriuretic peptide, creatinine, left ventricular (LV) end-diastolic volume, LV end-systolic volume, right ventricular (RV) end-diastolic volume and RVpGLS from CMR were associated with the outcomes. The multivariate Cox regression model adjusting for traditional risk factors and CMR variables detected a significant association between RVpGLS and MACEs in patients with stage C or D HF with NIDCM without AF. Kaplan-Meier analysis based on RVpGLS cut-off value revealed that patients with RVpGLS <-8.5% showed more favourable clinical outcomes than those with RVpGLS ≥-8.5% (p=0.0037). Subanalysis found that this association remained unchanged.

CONCLUSIONS

RVpGLS-derived from 3D CMR FT is associated with a significant prognostic impact in patients with NIDCM with stage C or D HF and without AF.

Nuclear cardiology: state of the art

Radionuclide imaging remains an essential component of modern cardiology. There is overlap with the information from other imaging techniques, but no technique is static and new developments have expanded its role. This review focuses on ischaemic heart disease, heart failure, infection and inflammation. Radiopharmaceutical development includes the wider availability of positron emission tomography (PET) tracers such as rubidium-82, which allows myocardial perfusion to be quantified in absolute terms. Compared with alternative techniques, myocardial perfusion scintigraphy PET and single photon emission computed tomography (SPECT) have the advantages of being widely applicable using exercise or pharmacological stress, full coverage of the myocardium and a measure of ischaemic burden, which helps to triage patients between medical therapy and revascularisation. Disadvantages include the availability of expertise in some cardiac centres and the lack of simple SPECT quantification, meaning that global abnormalities can be underestimated. In patients with heart failure, despite the findings of the STICH (Surgical Treatment for Ischemic Heart Failure) trial, there are still data to support the assessment of myocardial hibernation in predicting when abolition of ischaemia might lead to improvement in ventricular function. Imaging of sympathetic innervation is well validated, but simpler markers of prognosis mean that it has not been widely adopted. There are insufficient data to support its use in predicting the need for implanted devices, but non-randomised studies are promising. Other areas where radionuclide imaging is uniquely valuable are detection and monitoring of endocarditis, device infection, myocardial inflammation in sarcoidosis, myocarditis and so on, and reliable detection of deposition in suspected transthyretin-related amyloidosis.

Cardiovascular magnetic resonance imaging: emerging techniques and applications

This review gives examples of emerging cardiovascular magnetic resonance (CMR) techniques and applications that have the potential to transition from research to clinical application in the near future. Four-dimensional flow CMR (4D-flow CMR) allows time-resolved three-directional, three-dimensional (3D) velocity-encoded phase-contrast imaging for 3D visualisation and quantification of valvular or intracavity flow. Acquisition times of under 10 min are achievable for a whole heart multidirectional data set and commercial software packages are now available for data analysis, making 4D-flow CMR feasible for inclusion in clinical imaging protocols. Diffusion tensor imaging (DTI) is based on the measurement of molecular water diffusion and uses contrasting behaviour in the presence and absence of boundaries to infer tissue structure. Cardiac DTI is capable of non-invasively phenotyping the 3D micro-architecture within a few minutes, facilitating transition of the method to clinical protocols. Hybrid positron emission tomography-magnetic resonance (PET-MR) provides quantitative PET measures of biological and pathological processes of the heart combined with anatomical, morphological and functional CMR imaging. Cardiac PET-MR offers opportunities in ischaemic, inflammatory and infiltrative heart disease.

Cost-effectiveness of cardiovascular imaging for stable coronary heart disease

OBJECTIVE

To assess the cost-effectiveness of management strategies for patients presenting with chest pain and suspected coronary heart disease (CHD): (1) cardiovascular magnetic resonance (CMR); (2) myocardial perfusion scintigraphy (MPS); and (3) UK National Institute for Health and Care Excellence (NICE) guideline-guided care.

METHODS

Using UK data for 1202 patients from the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease 2 trial, we conducted an economic evaluation to assess the cost-effectiveness of CMR, MPS and NICE guidelines. Health outcomes were expressed as quality-adjusted life-years (QALYs), and costs reflected UK pound sterling in 2016-2017. Cost-effectiveness results were presented as incremental cost-effectiveness ratios and incremental net health benefits overall and for low, medium and high pretest likelihood of CHD subgroups.

RESULTS

CMR had the highest estimated QALY gain overall (2.21 (95% credible interval 2.15, 2.26) compared with 2.07 (1.92, 2.20) for NICE and 2.11 (2.01, 2.22) for MPS) and incurred comparable costs (overall £1625 (£1431, £1824) compared with £1753 (£1473, £2032) for NICE and £1768 (£1572, £1989) for MPS). Overall, CMR was the cost-effective strategy, being the dominant strategy (more effective, less costly) with incremental net health benefits per patient of 0.146 QALYs (-0.18, 0.406) compared with NICE guidelines at a cost-effectiveness threshold of £15 000 per QALY (93% probability of cost-effectiveness). Results were similar in the pretest likelihood subgroups.

CONCLUSIONS

CMR-guided care is cost-effective overall and across all pretest likelihood subgroups, compared with MPS and NICE guidelines.

Proportionate or disproportionate secondary mitral regurgitation: how to untangle the Gordian knot?

Recent randomised percutaneous mitral intervention trials in patients with heart failure with secondary mitral regurgitation (SMR) have yielded contrasting results. A 'relative load' or 'proportionality' conceptual framework for SMR has been proposed to partly explain the disparate results. The rationale behind the framework is that SMR depends on the left ventricular dimension and not vice versa. In this review, we provide an in-depth analysis of the proportionality parameters used in this framework and also discuss the regurgitant fraction. We also consider haemodynamic observations in SMR that may affect the interpretation and comparisons among proportionality parameters. The conclusion is that the proportionality concept remains hypothetical and requires prospective validation before envisaging its use at individual patient level for risk stratification or therapeutic decision-making.

Association between right ventricle dysfunction and poor outcome in patients with septic shock

OBJECTIVE

Sepsis-induced myocardial dysfunction (SIMD) can involve both the left and right ventricles. However, the characteristics and outcomes across various manifestations of SIMD remain unknown.

METHODS

This was a retrospective cohort study using a prospective registry of septic shock from January 2011 and April 2017. Patients with clinically presumed cardiac dysfunction underwent echocardiography within 72 hours after admission and were enrolled (n=778). SIMD was classified as left ventricle (LV) systolic/diastolic and right ventricle (RV) dysfunction, which were defined based on the American Society of Echocardiography criteria. The primary outcome was 28-day mortality.

RESULTS

Of the 778 septic shock patients who underwent echocardiography, 270 (34.7%) showed SIMD. The median age was 67.0 years old, and the male was predominant (57.3%). Among them, 67.3% had LV systolic dysfunction, 40.7% had RV dysfunction and 39.3% had LV diastolic dysfunction. Although serum lactate level and sequential organ failure assessment score were not significantly different between groups, SIMD group showed higher troponin I (0.1 vs 0.1 ng/mL; p=0.02) and poor clinical outcomes, including higher 28-day mortality (35.9 vs 26.8%; p<0.01), longer intensive care unit length of stay (5 vs 2 days; p<0.01) and prolonged mechanical ventilation (9 vs 4 days; p<0.01). Multivariate analysis showed that isolated RV dysfunction was an independent risk factor of 28-day mortality (OR 2.26, 95% CI 1.04 to 4.91).

CONCLUSIONS

One-third of patients with septic shock showed various myocardial dysfunctions. LV systolic dysfunction was common; however, only RV dysfunction was associated with short-term mortality.

Augmentation of pulmonary blood flow and cardiac output by non-invasive external ventilation late after Fontan palliation

Objectives

Although a life-preserving surgery for children with single ventricle physiology, the Fontan palliation is associated with striking morbidity and mortality with advancing age. Our primary objective was to evaluate the impact of non-invasive, external, thoraco-abdominal ventilation on pulmonary blood flow (PBF) and cardiac output (CO) as measured by cardiovascular magnetic resonance (CMR) imaging in adult Fontan subjects.

Methods

Adults with a dominant left ventricle post-Fontan palliation (lateral tunnel or extracardiac connections) and healthy controls matched by sex and age were studied. We evaluated vascular flows using phase-contrast CMR imaging during unassisted breathing, negative pressure ventilation (NPV) and biphasic ventilation (BPV). Measurements were made within target vessels (aorta, pulmonary arteries, vena cavae and Fontan circuit) at baseline and during each ventilation mode.

Results

Ten Fontan subjects (50% male, 24.5 years (IQR 20.8–34.0)) and 10 matched controls were studied. Changes in PBF and CO, respectively, were greater following BPV as compared with NPV. In subjects during NPV, PBF increased by 8% (Δ0.20 L/min/m² (0.10–0.53), p=0.011) while CO did not change significantly (Δ0.17 L/min/m² (−0.11–0.23), p=0.432); during BPV, PBF increased by 25% (Δ0.61 L/min/m² (0.20–0.84), p=0.002) and CO increased by 16% (Δ0.47 L/min/m² (0.21–0.71), p=0.010). Following BPV, change in PBF and CO were both significantly higher in subjects versus controls (0.61 L/min/m² (0.2–0.84) vs −0.27 L/min/m² (−0.55–0.13), p=0.001; and 0.47 L/min/m² (0.21–0.71) vs 0.07 L/min/m² (−0.47–0.33), p=0.034, respectively).

Conclusion

External ventilation acutely augments PBF and CO in adult Fontan subjects. Confirmation of these findings in larger populations with longer duration of ventilation and extended follow-up will be required to determine sustainability of haemodynamic effects.

Spondylodiscitis complicating infective endocarditis

OBJECTIVE

The primary objective was to assess the characteristics and prognosis of pyogenic spondylodiscitis (PS) in patients with infective endocarditis (IE). The secondary objectives were to assess the factors associated with occurrence of PS.

METHODS

Prospective case-control bi-centre study of 1755 patients with definite IE with (n=150) or without (n=1605) PS. Clinical, microbiological and prognostic variables were recorded.

RESULTS

Patients with PS were older (mean age 69.7±18 vs 66.2±14; p=0.004) and had more arterial hypertension (48% vs 34.5%; p<0.001) and autoimmune disease (5% vs 2%; p=0.03) than patients without PS. The lumbar vertebrae were the most frequently involved (84 patients, 66%), especially L4-L5. Neurological symptoms were observed in 59% of patients. Enterococci and Streptococcus gallolyticus were more frequent (24% vs 12% and 24% vs 11%; p<0001, respectively) in the PS group. The diagnosis of PS was based on contrast-enhanced MRI in 92 patients, bone CT in 88 patients and ¹⁸F-FDG PET/CT in 56 patients. In-hospital (16% vs 13.5%, p=0.38) and 1-year (21% vs 22%, p=0.82) mortalities did not differ between patients with or without PS.

CONCLUSIONS

PS is a frequent complication of IE (8.5% of IE), is observed in older hypertensive patients with enterococcal or S. gallolyticus IE, and has a similar prognosis than other forms of IE. Since PS is associated with specific management, multimodality imaging including MRI, CT and PET/CT should be used for early diagnosis of this complication of endocarditis.

Comprehensive review of evaluation and management of cardiac paragangliomas

Cardiac paraganglioma (PGL) is a rare neuroendocrine tumour causing significant morbidity primarily due to norepinephrine secretion potentially causing severe hypertension, palpitations, lethal tachyarrhythmias, stroke and syncope. Cardiologists are faced with two clinical scenarios. The first is the elevated norepinephrine, whose actions must be properly counteracted by adrenoceptor blockade to avoid catastrophic consequences. The second is to evaluate the precise location of a cardiac PGL and its spread since compression of cardiovascular structures may result in ischaemia, angina, non-noradrenergic-induced arrhythmia, cardiac dysfunction or failure. Thus, appropriate assessment of elevated norepinephrine by its metabolite normetanephrine is a gold biochemical standard at present. Furthermore, dedicated cardiac CT, MRI and transthoracic echocardiogram are necessary for the precise anatomic information of cardiac PGL. Moreover, a cardiologist needs to be aware of advanced functional imaging using ⁶⁸Ga-DOTA(0)-Tyr(3)-octreotide positron emission tomography/CT, which offers the best cardiac PGL-specific diagnostic accuracy and helps to stage and rule out metastasis, determining the next therapeutic strategies. Patients should also undergo genetic testing, especially for mutations in genes encoding succinate dehydrogenase enzyme subunits that are most commonly present as a genetic cause of these tumours. Curative surgical resection after appropriate α-adrenoceptor and β-adrenoceptor blockade in norepinephrine-secreting tumours is the primary therapeutic strategy. Therefore, appropriate and up-to-date knowledge about early diagnosis and management of cardiac PGLs is paramount for optimal outcomes in patients where a cardiologist is an essential team member of a multidisciplinary team in its management.

The risk of misdiagnosis in acute thoracic aortic dissection: a review of current guidelines

Acute aortic syndrome and in particular aortic dissection (AAD) persists as a cause of significant morbidity and mortality despite improvements in surgical management. This clinical review aims to explore the risks of misdiagnosis, outcomes associated with misdiagnosis and evaluate current diagnostic methods for reducing its incidence.Due to the nature of the pathology, misdiagnosing the condition and delaying management can dramatically worsen patient outcomes. Several diagnostic challenges exist, including low prevalence, rapidly propagating pathology, non-discrete symptomatology, non-specific signs, analogy with other acute conditions and lack of management infrastructure. A similarity to acute coronary syndromes is a specific concern and risks patient maltreatment. AAD with malperfusion syndromes are both a cause of misdiagnosis and marker of disease complication, requiring specifically tailored management plans from the emergency setting.Despite improvements in diagnostic measures, including imaging modalities and biomarkers, misdiagnosis of AAD remains commonplace and current guidelines are relatively limited in preventing its occurrence. This paper recommends the early use of AAD risk scoring, focused echocardiography and most importantly, fast-tracking patients to cross-sectional imaging where the suspicion of AAD is high. This has the potential to improve the diagnostic process for AAD and limit the risk of misdiagnosis. However, our understanding remains limited by the lack of large patient datasets and an adequately audited processes of emergency department practice.

Cardiorespiratory fitness and heart rate recovery predict sudden cardiac death independent of ejection fraction

OBJECTIVE

To evaluate whether cardiorespiratory fitness (CRF) and heart rate recovery (HRR) associate with the risk of sudden cardiac death (SCD) independently of left ventricular ejection fraction (LVEF).

METHODS

The Finnish Cardiovascular Study is a prospective clinical study of patients referred to clinical exercise testing in 2001-2008 and follow-up until December 2013. Patients without pacemakers undergoing first maximal or submaximal exercise testing with cycle ergometer were included (n=3776). CRF in metabolic equivalents (METs) was estimated by achieving maximal work level. HRR was defined as the reduction in heart rate 1 min after maximal exertion. Adjudication of SCD was based on death certificates. LVEF was measured for clinical indications in 71.4% of the patients (n=2697).

RESULTS

Population mean age was 55.7 years (SD 13.1; 61% men). 98 SCDs were recorded during a median follow-up of 9.1 years (6.9-10.7). Mean CRF and HRR were 7.7 (SD 2.9) METs and 25 (SD 12) beats/min/min. Both CRF and HRR were associated with the risk of SCD in the entire study population (HR_CRF0.47 (0.37-0.59), p<0.001 and HR_HRR0.57 (0.48-0.67), p<0.001 with HR estimates corresponding to one SD increase in the exposure variables) and with CRF, HRR and LVEF in the same model (HR_CRF0.60 (0.45-0.79), p<0.001, HR_HRR0.65 (0.51-0.82), p<0.001) or adjusting additionally for all significant risk factors for SCD (LVEF, sex, creatinine level, history of myocardial infarction and atrial fibrillation, corrected QT interval) (HR_CRF0.69 (0.52-0.93), p<0.01, HR_HRR0.74 (0.58-0.95) p=0.02).

CONCLUSIONS

CRF and HRR are significantly associated with the risk of SCD regardless of LVEF.

Valve area and the risk of overestimating aortic stenosis

OBJECTIVE

To obtain reference values of aortic valve area (AVA) in a large population and to infer the risk of overestimating aortic stenosis (AS) when focusing on flow-corrected indices of severity.

METHODS

We prospectively measured indices of AS in all consecutive echocardiograms performed in a large referral cardiac imaging laboratory for 1 year. We specifically analysed the distribution of AVA, indexed AVA and velocity ratio (Vratio) in patients with and without AS, the latter defined as the coexistence of valvular outflow obstruction (Vmax ≥2.5 m/s) and morphological findings of valve degeneration.

RESULTS

16 156 echocardiograms were analysed, 14 669 of which did not show valvular obstruction (peak jet velocity <2.5 m/s). In the latter group, AVA was 2.6±0.7 cm² in 8190 studies with normal valves and 2.3±0.7 cm² in 6479 studies with aortic sclerosis (AScl). There was a relatively wide overlap between values of AVA, indexed AVA and velocity ratio between studies of patients with AScl and AS. Values of AVA ≤1.0 cm² were found in 0.5% of studies with normal valves and 1.8% of studies with AScl. These proportions were 3.1% and 9.3% for AVA ≤1.5 cm², respectively. Vratio ≤0.25 were found in 0.1% of patients without obstruction. Risk factors for a small AVA in patients without obstruction were AScl, female sex, small body surface area, low ejection fraction and mitral regurgitation.

CONCLUSIONS

Normal values of continuity-equation derived AVA are smaller than previously considered. AVA values below cutoffs of moderate or severe AS can be found in patients without the disease. Flow-corrected indices may overestimate AS in patients with low gradients, particularly in the presence of well-identified risk factors.

The challenge of asymptomatic coronary artery disease in aircrew; detecting plaque before the accident

Coronary events remain a major cause of sudden incapacitation, including death, in both the general population and among aviation personnel, and are an ongoing threat to flight safety and operations. The presentation is often unheralded, especially in younger adults, and is often due to rupture of a previously non-obstructive coronary atheromatous plaque. The challenge for aeromedical practitioners is to identify individuals at increased risk for such events. This paper presents the NATO Cardiology Working Group (HFM 251) consensus approach for screening and investigation of aircrew for asymptomatic coronary disease.A three-phased approach to coronary artery disease (CAD) risk assessment is recommended, beginning with initial risk-stratification using a population-appropriate risk calculator and resting ECG. For aircrew identified as being at increased risk, enhanced screening is recommended by means of Coronary Artery Calcium Score alone or combined with a CT coronary angiography investigation. Additional screening may include exercise testing, and vascular ultrasound imaging. Aircrew identified as being at high risk based on enhanced screening require secondary investigations, which may include functional ischaemia, and potentially invasive coronary angiography. Functional stress testing as a stand-alone investigation for significant CAD is not recommended in aircrew. Aircrew identified with coronary disease require further clinical and aeromedical evaluation before being reconsidered for flying status.

Tachycardia after acute deceleration injury

A 29-year-old man crashed at high speed into another vehicle at traffic lights. He was able to get out of his van but then collapsed after running a few metres. On arrival in the emergency department he was conscious, with a pulse of 140 beats/min and blood pressure of 110/32 mm Hg. He had collapsing arterial pulses and an early diastolic murmur. He had a chest radiograph (figure 1A) and a skeletal survey which demonstrated multiple fractures, involving his left hand, right femur, right calcaneus, and left first and second ribs. A CT scan of the thorax was performed with a radiological contrast agent but without gated images because of the tachycardia (Figure 1B). The blood pressure and pulse were attributed to blood loss into the right thigh. Urgent cardiology review and bedside echocardiography were requested before he had emergency orthopaedic surgery (figure 1C, D) (online supplementary video 1).DC1SP110.1136/heartjnl-2018-314082.supp1Supplementary file 1heartjnl;105/5/398/F1F1F1Figure 1(A-D) Chest radiograph, CT thorax with contrast, parasternal long-axis transthoracic view (grey scale) and with colour flow. The arrow in section C highlights the area of significance (mobile linear structure). QUESTION: What is the most likely diagnosis?Traumatic dissection of the aortic root.Subaortic membrane or diaphragm.Traumatic transection of the aorta.Traumatic rupture of the aortic valve.Myocardial rupture.

Fourteen-year-old boy with decreased appetite and pedal swelling

CLINICAL INTRODUCTION: A 14-year-old boy presented with history of decreased appetite and bilateral swelling of feet for 6 months. He did not give any associated history of orthopnoea or paroxysmal nocturnal dyspnoea. He was born by a normal delivery after a non-consanguineous marriage. He had an unremarkable birth and childhood health history. There was no family history of significant cardiovascular illness or sudden death. Clinical examination showed an average built boy with elevated jugular venous pressure with prominent v wave and bilateral pitting pedal oedema. Cardiovascular examination showed normal first (S1) and second (S2) heart sounds and a short early systolic murmur over tricuspid region. Other systems examination was remarkable for soft tender hepatomegaly.ECG showed sinus rhythm with tall, peaked p waves. Chest X-ray revealed enlargement along the right cardiac border. Transthoracic echocardiographic images are shown in figure 1A (apical four-chamber view) and figure 1B (tricuspid inflow Doppler). There was no colour Doppler evidence of interatrial shunt.heartjnl;105/5/405/F1F1F1Figure 1(A) Transthoracic echocardiographic apical four-chamber view. (B) Tricuspid inflow continuous wave Doppler image. QUESTION: What is the most likely diagnosis of his condition? Endomyocardial fibrosis (EMF)Ebstein's anomalyArrhythmogenic right ventricular dysplasia (ARVD)Idiopathic dilatation of right atriumRestrictive cardiomyopathy.

Integration of echocardiographic screening by non-physicians with remote reading in primary care

INTRODUCTION

Heart disease (HD) accounts for high morbidity and mortality in Brazil. Underserved populations often suffer long delays in diagnosis. We aimed to evaluate the feasibility of integrating screening echocardiography (echo) with remote interpretation in the established primary care system (PC) in Brazil and to assess HD prevalence.

METHODS

Over 11 months, 20 healthcare workers (four physicians, four nurses, and 12 technicians) at 16 PC centres were trained on simplified handheld echo protocols. Three screening (SC) groups, including all consented patients aged 17-20, 35-40 and 60-65 years, and patients referred (RF) for clinical indications underwent focused echo. Studies were remotely interpreted through telemedicine. Significant HD was defined as moderate/severe valve disease, ventricular dysfunction/hypertrophy, pericardial effusion, wall-motion abnormalities and congenital heart disease.

RESULTS

Total 1004 patients underwent echo; 299 (29.8%) in the SC group. Median age was 51±18 years, 63.9% females; 42.7% had cardiovascular symptoms. Significant HD was found in 354 (35.3%) patients (23.4% in SC vs 40.3% in RF group, p<0.001). Prevalence was higher in patients in the SC group aged >60 years (29.2%), compared with 35-40 (14.9%) and under 20 (16.5%), p=0.012. Comparing SC to RF groups, moderate/severe left ventricular dysfunction was observed in 4.1% vs 8.1%, p=0.03, mitral regurgitation in 8.9% vs 20.3%, p<0.001 and aortic stenosis in 5.4% vs 4.3%, p=0.51.

CONCLUSIONS

Integration focused echo into PC is feasible in Brazil as a strategy to deliver cardiovascular care to low-resourced areas through task shifting. The burden of HD observed suggests this tool may improve early diagnosis and referral.

Biomarkers to diagnose ventricular dysfunction in childhood cancer survivors: a systematic review

OBJECTIVE

To systematically review the literature and assess the diagnostic value of biomarkers in detection of late-onset left ventricular (LV) dysfunction in childhood cancer survivors (CCS) treated with anthracyclines.

METHODS

We systematically searched the literature for studies that evaluated the use of biomarkers for detection of LV dysfunction in CCS treated with anthracyclines more than 1 year since childhood cancer diagnosis. LV dysfunction definitions were accepted as an ejection fraction <50% or <55% and/or a fractional shortening <28%, <29% or <30%. Contingency tables were created to assess diagnostic accuracies of biomarkers for diagnosing LV dysfunction.

RESULTS

Of 1362 original studies screened, eight heterogeneous studies evaluating four different biomarkers in mostly asymptomatic CCS were included. In four studies, an abnormal N-terminal pro-B-type natriuretic peptide (NT-proBNP, cut-off range 63-125 ng/L) had low sensitivity (maximally 22%) and a specificity of up to 97% for detection of LV dysfunction. For troponin levels, in five studies one patient had an abnormal troponin value as well as LV dysfunction, while in total 127 patients had LV dysfunction without troponin elevations above cut-off values (lowest 0.01 ng/mL). Two studies that evaluated brain natriuretic peptide and nitric oxide were underpowered to draw conclusions.

CONCLUSIONS

In individual studies, the diagnostic value of NT-proBNP for detection of LV dysfunction in CCS is limited. Troponins have no role in detecting late-onset LV dysfunction with cut-off values as low as 0.01 ng/mL. Further study on optimal NT-proBNP cut-off values for rule out or rule in of LV dysfunction is warranted.

Applying the ordinal model of atherosclerosis to imaging science: a brief review

Atherogenesis has been well demonstrated to proceed in an ordinal fashion. Imaging technologies have advanced substantially in recent decades, enabling early detection of atherosclerosis. Some modalities, such as coronary CT, have seen broad clinical adaptation. In contrast, others, such as flow-mediated dilatation, remain predominantly research-based. Optimal and appropriate usage of these technologies remains an area of active investigation. We hypothesise that investigators ought to consider which stage of atherosclerosis is under investigation when choosing imaging modalities. Additionally, when assessing the efficacy of a particular treatment, some imaging modalities may be more appropriate than others. We review the most important available imaging modalities and suggest stages at which each may or may not be well used. Conceptual application of the classic stages of atherosclerosis model to the variety of modern imaging modalities available will result in more effective investigation and treatment of cardiovascular disease.

Pericardial mass in a 71-year-old man

CLINICAL INTRODUCTION: A 71-year-old man, with a history of chronic aortic regurgitation and negative follow-up after bladder cancer resection 10 months before, had an aortic valve surgery. Two months after, a mass near the right side of the heart had been detected by transthoracic echocardiography performed for dyspnoea, without a cough or fever. The quality of ultrasound images did not allow for an appropriate evaluation due to the outcomes of the sternotomy and the presence of calcified pachypleurite. In order to evaluate this finding, coronary CT (CCT) (figure 1A,B) and positron-emission tomography with 2-[18F] fluoro-2-deoxy-D-glucose (FDG-PET) (figure 1C) were performed. Finally, a cardiac magnetic resonance (CMR) was requested (figure 1D-F, see online supplementary videos).heartjnl;104/23/1936/F1F1F1Figure 1(A) Short axis image of early contrast enhancement phase coronary CT (CCT); (B) short axis of delayed phase of the same CCT; (C) lesion on positron-emission tomography with 2-[18F] fluoro-2-deoxy-D-glucose image (white arrow); CMR short axis (D) T2-weighted image with fat saturation; (E) T1-weighted image with fat-saturation; (F) T1-weighted image without fat-saturation. QUESTION: Which of the following is the most likely diagnosis of the pericardial mass?Primary pericardial tumour.Pericardial metastasis.Intrapericardial abscess.Intrapericardial haematoma.

Diastolic stress echocardiography: from basic principles to clinical applications

Heart failure with preserved ejection fraction (HFpEF) looms as a major public heart challenge with increasing prevalence due to an ageing population. Diagnosis can be challenging due to non-specific symptomatology, low natriuretic peptide levels and equivocal diastology on resting echocardiography. Diastolic stress echocardiography represents a non-invasive option to refining the diagnosis in this subset of patients. Diastolic responses to exercise are most commonly measured with a non-invasive measure of left ventricular filling pressures (LVFP) estimated by the ratio of the early mitral inflow wave to early diastolic tissue velocity (E/e' ratio). This is measured pre- and post-exercise , and is highly feasible. An elevation of exercise E/e' >15 is classified as an abnormal response as per current guidelines. An alternative measure of exercise-related diastolic performance, the Diastolic Functional Reserve Index has also been proposed, but has not been as well studied as exercise E/e'. A number of studies have validated exercise E/e' as a measure of LVFP against invasively measured LVFP using simultaneous echocardiography-catheterisation studies. The independent prognostic value of exercise E/e' has also been well delineated in a number of studies. While diastolic stress echocardiography can be considered for all patients with suspected HFpEF, it is of particular value in patients with normal or equivocal diastolic indices on resting echocardiography.

Validity of inducible ischaemia as a surrogate for adverse outcomes in stable coronary artery disease

Regional myocardial ischaemia is commonly expressed as exertional angina in patients with stable coronary artery disease (CAD). It also associates with prognosis, risk tending to increase with the severity of ischaemia. The validity of myocardial ischaemia as a surrogate for adverse clinical outcomes, however, has not been well established. Thus, in cohort studies, ischaemia testing has failed to influence rates of myocardial infarction and coronary death. Moreover, in clinical studies, pharmacological and interventional treatments that are effective in correcting ischaemia have rarely been shown to reduce cardiovascular (CV) risk. This contrasts with statins and other anti-inflammatory drugs that have no direct effect on ischaemia but improve CV outcomes by modifying the atherothrombotic disease process. Despite this, and with little evidence of patient benefit, stress testing is commonly used during the follow-up of patients with stable CAD when the demonstration of ischaemic change may be seen as a target for treatment, independently of symptomatic status. Substitution of a symptom-driven management strategy has the potential to reduce rates of non-invasive stress testing, unnecessary downstream revascularisation procedures and use of valuable resources in patients with stable CAD without adverse consequences for CV risk.

Asymptomatic young man with an incidental murmur

CLINICAL INTRODUCTION

A 32-year old man was referred to our institution for transthoracic echocardiography (TTE) following detection of an incidental murmur on physical examination before blood donation. He was asymptomatic with no significant medical history. Physical examination revealed dual heart sounds with a grade II/VI systolic murmur heard in the left sternal border. An ECG was in normal sinus rhythm. TTE was performed (figure 1A-C, online supplementary videos 1-4) followed by cardiac CT angiography (CTA) (figure 1D,E).heartjnl;104/15/1307/F1F1F1Figure 1(A) Transthoracic echocardiography, parasternal left ventricular long axis view. (B) Colour Doppler of modified short axis in the mid-left ventricular level. (C) Doppler flow velocity profile. (D) Cardiac CT angiography (CTA) sagittal reconstruction. (E) Three-dimensional CTA reconstruction of the heart.

QUESTION

What is the diagnosis?Pericardial cyst.Ventricular septal defect.Kawasaki.Anomalous left coronary artery from pulmonary artery (ALCAPA).

Arterial stiffness association with chronic inflammatory disorders in the UK Biobank study

OBJECTIVE

The present study tested the hypothesis that arterial stiffness will be elevated across overall and specific inflammatory disorders compared with an inflammation-free comparison group.

METHODS

Adults (n=171 125) aged 40-70 years from the UK Biobank who were cardiovascular disease (CVD) free and who had their arterial stiffness assessed at the time of study recruitment between 2006 and 2010 were included. The main exposure was represented by a global measure of chronic inflammatory disorders. Two inflammatory biomarker measures (eg, leucocytes count, granulocytes count) were included as markers of inflammation severity. The arterial stiffness index assessed by a non-invasive technique represented the study primary outcome measure.

RESULTS

A total of 5976 (3%) participants diagnosed with inflammatory disorders and 165 149 participants without an inflammatory disorder had data on arterial stiffness. Adjusted linear regression analyses revealed a 14% increment in mean arterial stiffness for chronic inflammatory disorders (beta coefficient (β) 1.14, 95% CI 1.05 to 1.24, P=0.002) compared with no chronic inflammatory disorder. Arterial stiffness tended to increase (P value=0.031) with tertiles of leucocytes and granulocytes count. For instance, mean arterial stiffness values increased from 1.11 (95% CI 0.96 to 1.29) in the first tertile to 1.17 (95% CI 1.02 to 1.34) in the second tertile, and 1.21 (95% CI 1.05 to 1.39) in the third tertile of leucocytes count. There was evidence for similar associations with some of the most common individual inflammatory disorders, including psoriasis and rheumatoid arthritis.

CONCLUSION

Arterial stiffness was associated with multiple chronic inflammatory disorders. An increasing trend in mean arterial stiffness was also documented with increasing tertiles of different inflammatory biomarkers. Future studies are needed to investigate the discriminant value of arterial stiffness to predict major CVD events within various inflammatory disorders.

Advances in computational modelling for personalised medicine after myocardial infarction

Myocardial infarction (MI) is a leading cause of premature morbidity and mortality worldwide. Determining which patients will experience heart failure and sudden cardiac death after an acute MI is notoriously difficult for clinicians. The extent of heart damage after an acute MI is informed by cardiac imaging, typically using echocardiography or sometimes, cardiac magnetic resonance (CMR). These scans provide complex data sets that are only partially exploited by clinicians in daily practice, implying potential for improved risk assessment. Computational modelling of left ventricular (LV) function can bridge the gap towards personalised medicine using cardiac imaging in patients with post-MI. Several novel biomechanical parameters have theoretical prognostic value and may be useful to reflect the biomechanical effects of novel preventive therapy for adverse remodelling post-MI. These parameters include myocardial contractility (regional and global), stiffness and stress. Further, the parameters can be delineated spatially to correspond with infarct pathology and the remote zone. While these parameters hold promise, there are challenges for translating MI modelling into clinical practice, including model uncertainty, validation and verification, as well as time-efficient processing. More research is needed to (1) simplify imaging with CMR in patients with post-MI, while preserving diagnostic accuracy and patient tolerance (2) to assess and validate novel biomechanical parameters against established prognostic biomarkers, such as LV ejection fraction and infarct size. Accessible software packages with minimal user interaction are also needed. Translating benefits to patients will be achieved through a multidisciplinary approach including clinicians, mathematicians, statisticians and industry partners.

Diagnostic performance of an acoustic-based system for coronary artery disease risk stratification

OBJECTIVE

Diagnosing coronary artery disease (CAD) continues to require substantial healthcare resources. Acoustic analysis of transcutaneous heart sounds of cardiac movement and intracoronary turbulence due to obstructive coronary disease could potentially change this. The aim of this study was thus to test the diagnostic accuracy of a new portable acoustic device for detection of CAD.

METHODS

We included 1675 patients consecutively with low to intermediate likelihood of CAD who had been referred for cardiac CT angiography. If significant obstruction was suspected in any coronary segment, patients were referred to invasive angiography and fractional flow reserve (FFR) assessment. Heart sound analysis was performed in all patients. A predefined acoustic CAD-score algorithm was evaluated; subsequently, we developed and validated an updated CAD-score algorithm that included both acoustic features and clinical risk factors. Low risk is indicated by a CAD-score value ≤20.

RESULTS

Haemodynamically significant CAD assessed from FFR was present in 145 (10.0%) patients. In the entire cohort, the predefined CAD-score had a sensitivity of 63% and a specificity of 44%. In total, 50% had an updated CAD-score value ≤20. At this cut-off, sensitivity was 81% (95% CI 73% to 87%), specificity 53% (95% CI 50% to 56%), positive predictive value 16% (95% CI 13% to 18%) and negative predictive value 96% (95% CI 95% to 98%) for diagnosing haemodynamically significant CAD.

CONCLUSION

Sound-based detection of CAD enables risk stratification superior to clinical risk scores. With a negative predictive value of 96%, this new acoustic rule-out system could potentially supplement clinical assessment to guide decisions on the need for further diagnostic investigation.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier NCT02264717; Results.

Molecular imaging of atherosclerosis: spotlight on Raman spectroscopy and surface-enhanced Raman scattering

To accurately predict atherosclerotic plaque progression, a detailed phenotype of the lesion at the molecular level is required. Here, we assess the respective merits and limitations of molecular imaging tools. Clinical imaging includes contrast-enhanced ultrasound, an inexpensive and non-toxic technique but with poor sensitivity. CT benefits from high spatial resolution but poor sensitivity coupled with an increasing radiation burden that limits multiplexing. Despite high sensitivity, positron emission tomography and single-photon emission tomography have disadvantages when applied to multiplex molecular imaging due to poor spatial resolution, signal cross talk and increasing radiation dose. In contrast, MRI is non-toxic, displays good spatial resolution but poor sensitivity. Preclinical techniques include near-infrared fluorescence (NIRF), which provides good spatial resolution and sensitivity; however, multiplexing with NIRF is limited, due to photobleaching and spectral overlap. Fourier transform infrared spectroscopy and Raman spectroscopy are label-free techniques that detect molecules based on the vibrations of chemical bonds. Both techniques offer fast acquisition times with Raman showing superior spatial resolution. Raman signals are inherently weak; however, leading to the development of surface-enhanced Raman spectroscopy (SERS) that offers greatly increased sensitivity due to using metallic nanoparticles that can be functionalised with biomolecules targeted against plaque ligands while offering high multiplexing potential. This asset combined with high spatial resolution makes SERS an exciting prospect as a diagnostic tool. The ongoing refinements of SERS technologies such as deep tissue imaging and portable systems making SERS a realistic prospect for translation to the clinic.

Progressive breathlessness following transcatheter aortic valve replacement

: An 84-year-old man presented urgently to the cardiology clinic with rapid onset exertional dyspnoea while walking on the flat. Five months previously, he underwent implantation of a balloon-expandable 26 mm transcatheter heart valve (SAPIEN 3, Edwards Lifesciences) for severe aortic stenosis. On clinical examination, the jugular venous pressure was elevated and a mid-late ejection systolic murmur was audible in the aortic region. ECG demonstrated sinus rhythm with a left ventricular (LV) strain pattern. Transthoracic echocardiography and cardiac CT were performed (figure 1). heartjnl;103/21/1703/F1F1F1Figure 1(A) Transthoracic continuous wave Doppler through the transcatheter AV. ECG-gated cardiac CT oblique reconstruction of the LV outflow tract and aortic root in mid-diastole (B) with axial reconstruction of the transcatheter AV in end-systole (inset). AT, acceleration time; AV, aortic valve; LV, left ventricular.

QUESTION

Which aetiology best explains this presentation?Pannus formationTranscatheter bioprosthetic valve endocarditisPatient-prosthesis mismatchTranscatheter bioprosthetic valve leaflet thrombosisStructural valve degeneration.

Subclinical leaflet thrombosis after transcatheter aortic valve implantation

Although clinically significant valve thrombosis after transcatheter aortic valve implantation (TAVI) is rare, the incidence of subclinical leaflet thrombosis has been reported to be up to about 10%-15%. It is mostly found 1-3 months after procedure in any type of transcatheter heart valve. Leaflet thrombosis is detected by high-resolution CT in the form of limited valve opening/closure and hypoattenuated leaflet thickening. Transthoracic or transesophageal echocardiography is capable of detecting limitations of valve motion, leaflet thickening, increased flow velocity across the valve. However, CT seems to be more sensitive than echocardiography to detect leaflet thrombosis. It can occur under dual antiplatelet therapy with aspirin and a thienopyridine but rarely occurs with anticoagulation with a vitamin K antagonist. A vitamin K antagonist is also helpful to resolve leaflet thrombosis. Several studies are ongoing to determine the effect of new oral anticoagulants (NOACs) in preventing major cardiovascular events. They will also provide useful information on whether NOACs prevent leaflet thrombosis.