Clinical articles

Typical echocardiographic assessment of left ventricle (LV) size is based on single-dimensional measurements at mitral valve leaflet tips. In ischaemic and non-ischaemic cardiomyopathy (ICM and NICM) and aortic regurgitation (AR) where spherical remodelling is observed, this single-dimensional measurement at the LV base may underestimate LV volume. We hypothesised the maximum diameter would provide a closer approximation. A retrospective analysis of 1,680 consecutive cardiovascular magnetic resonance (CMR) examinations identified 82 patients with substantial LV dilation (LVEDVi >130 ml/m²) and 23 controls. LV end-diastolic and end-systolic diameters were measured using echocardiography and CMR at the standard level (EDD_MV and ESD_MV) and the maximum diameter (EDD_max and ESD_max). Indexed diameters were fitted to indexed volumes using cubic regressions. Maximum diameters had higher R² values in fitting LV volume, and improved categorisation of subjects with chamber enlargement without substantially increasing the false-positive rate. Standard measurements may underestimate LV volume in cases of spherical remodelling, use of the maximum dimension may be a straightforward approach to improve assessment of LV volume and remodelling.

Integration of healthcare services has been advocated to improve quality and cost-effectiveness. Different models of integrated care for cardiology have been suggested, but the cost-effectiveness of a consultant-run service has been questioned. We assessed the potential impact on secondary-care outpatient volumes of introducing a service run by GPs with a special interest, with support from consultant cardiologists. We retrospectively reviewed all cardiology outpatient attendances at the South London Healthcare NHS Trust for a period of three months in 2011. Using National Institute for Health and Care Excellence (NICE) guidelines and discussions between cardiologists and GPs, a novel outpatient referral triage protocol was drawn-up to decide the appropriate minimum level of care required for a range of cardiac conditions. Anonymised clinic letters were divided into new referrals and follow-ups, and were assessed to establish the diagnosis and clinical complexity. Implementing such an integrated community care service (ICC) would reduce new referrals to secondary care by 33%, and would enable transfer of 44% of patients currently followed up in secondary care to ICC. The study confirms that there is scope for significant transfer of care with the greatest gains in patients with valve disease, ischaemic heart disease and atrial fibrillation.

Venous thromboembolism (VTE) is a common cardiovascular disorder associated with considerable morbidity and mortality. The standard treatment for VTE comprises parenteral heparin overlapping with, and followed by, a vitamin K antagonist, which, although effective, has several limitations. Currently, many patients commence treatment for VTE in hospital and are discharged after 5–10 days to ongoing care in the community. With the introduction of non-vitamin K oral anticoagulants (NOACs), there is now the possibility for the complete management of patients with uncomplicated VTE to be undertaken by primary care, reducing the burden on hospitals and improving the patient experience. The NOAC rivaroxaban, a direct factor Xa inhibitor, has been widely approved for the treatment of VTE. This article offers guidance to general practitioners on the practical use of rivaroxaban for the treatment of patients with VTE, along with a discussion of its potential benefits compared with standard therapy.

Troponin testing is the cornerstone diagnostic test for evaluating acute coronary syndromes (ACS). Evidence suggests this test is increasingly being utilised in a less specific fashion. We sought to evaluate the appropriateness of bedside point-of-care (POC) troponin T (TnT) sampling in our hospital.

We examined the case records for 109 consecutive patients who underwent admission troponin testing. We reviewed the clinical presentation, baseline electrocardiogram (ECG) and final diagnoses.

Only 55% of patients presented with actual cardiac chest pain. A troponin-positive result was found in 19.2% of patients (n=21); however, only half of these had a final diagnosis of ACS. The troponin assay was negative in 80.8% of patients (n=88); under one-quarter of these (n=16) underwent further ischaemia assessment. Almost one-third of patients had neither chest pain nor ECG changes (n=35), but still underwent troponin testing. None had a final diagnosis of coronary artery disease.

Troponin assays are requested for patients with a relatively low suspicion of an ACS. A failure to undertake further ischaemia assessment suggests a lack of initial conviction of a cardiac diagnosis. True ACS was diagnosed in less than half of troponin-positive cases. These data support a need for more selective usage.

Early identification of atrial fibrillation (AF), especially when asymptomatic, is increasingly important when there are interventions that can reduce the risk of stroke. One mobile ECG device that has the potential for doing just that is the AliveCor® device, which is non-invasive and easy to use. We aimed to assess its utility in primary care by establishing its sensitivity and specificity, and consider the predictive value for identifying AF in a general practice population.

We used the device on a population known to have AF in order to calculate the sensitivity, and on a population who did not have AF at the time of recording, to establish specificity. Using the known prevalence of AF in a UK population, we were able to calculate the predictive values for identification of AF. All AliveCor® traces we compared with a gold-standard 12-lead electrocardiogram (ECG).

The device has a high sensitivity and specificity in the hands of experienced clinicians. In particular, the sensitivity was consistently high, which would ensure a high true-positive rate of identification. Furthermore, the negative predictive value in populations with a prevalence of AF as in the UK is sufficiently high to be useful.

In conclusion, the AliveCor® device should be considered as an option for early identification of patients with unknown AF. It has a high negative-predictive value and is sufficiently sensitive to be useful in a general practice population, but does not rule out the need for a definitive ECG in suspected cases.

We present a review of transcatheter aortic valve implantation (TAVI) in the presence of a mechanical mitral valve. We conclude that in patients with a prior mechanical prosthesis, TAVI is feasible and can be carried out without complication. Based on proof of feasibility, evidence to date would suggest that patients with mechanical prostheses be actively considered for TAVI going forward. 

Data have suggested that in vivo cardiac orientation has the greatest effect on the cardiac electric field, and, thus, surface electrical activity. We sought to determine the correlation between in vivo cardiac orientation using cardiac computed tomography (CT) and the electrical cardiac axis in the frontal plane determined by surface electrocardiogram (ECG). 

Patients aged between 30 and 60 years old with a normal body mass index (BMI), who underwent CT coronary angiography between July 2010 and December 2012 were included. Patients with diabetes, hypertension, arrhythmias, structural heart disease or thoracic deformities were excluded. In vivo cardiac orientation was determined along the long axis and correlated with the electrical cardiac axis on surface ECG.

There were 59 patients identified, with 47% male, mean age of 49.9 years and a mean BMI of 22.39 kg/m². The mean cardiac axis on CT was 38.1 ± 7.8°, while the mean electrical cardiac axis on ECG was 51.8 ± 26.6°. Bi-variate analysis found no correlation between the two readings (Pearson r value 0.12, p=0.37).

We conclude, there is no simple relationship between the anatomical cardiac axis and the ECG determined electrical axis of the heart. The electrical axis of the heart, however, showed more variability, reflecting possible underlying conduction disturbances.

Using the left trans-radial artery access route for coronary and bypass angiography has been frowned upon by the majority of operators due to several catheter changes during the procedure, patient discomfort because of spasm, positioning of the patients left arm and longer radiation exposure times, to name a few reasons. This short scientific article demonstrates one of a series of 22 cases where a single catheter was successfully used via this access route.

A 26-year-old man presented to the emergency department with central chest pain radiating to the left arm. An electrocardiogram (ECG) revealed inferior ST elevation. He had no major risk factors for cardiovascular disease, but habitually used synthetic cannabinoids (AKB48 and 5F-AKB48). A subsequent coronary angiogram showed occlusions in four obtuse marginal branches of the left circumflex artery and a large clot in the distal right coronary artery. The patient was treated with aspirin, ticagrelor, rivaroxaban and tirofiban infusion, and these occlusions were demonstrated to have resolved on a follow-up angiogram. The patient admitted smoking 5F-AKB48 four hours before the onset of chest pain. This case further strengthens the association between the use of synthetic cannabinoids and embolic-appearing myocardial infarction. This is the first report of myocardial infarction associated with the currently ‘legal-high’ 5F-AKB48, and may indicate the need for tighter regulation of this compound.

It is widely accepted that end-of-life care for non-cancer conditions has lagged behind that for cancer. The purpose of this survey was to evaluate the confidence of trainees in managing end-of-life issues. An online questionnaire was distributed to all registrar-grade British Junior Cardiac Association members in the UK.

A total of 219 trainees responded. Overall, 73% of trainees feel the care they provide patients with advanced heart failure is poor/adequate. Over 50% of trainees do not feel equipped to discuss advanced-care planning and end-of-life issues. There are 45% who report receiving no training in palliation of advanced heart failure symptoms, while 57% are unhappy with current provision of training. Trainees’ suggestions include more workplace-based supervision with additional regional and national training days, closer links with local hospices, and fellowships for cardiology trainees in palliative care.

Despite being part of the national curriculum for training in cardiology since 2010, trainees’ level of confidence in delivering end-of-life care in advanced heart failure and discussing prognosis is poor. This could be rectified by closer links with palliative care and formal teaching programmes.