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John Chambers

Echocardiography is the key to the detection and initial assessment of valve disease. The examination helps differentiate severe from moderate disease if this is unclear from the echocardiogram, but is less useful than echocardiography for surveillance. However the history is extremely important because symptoms are an indication for surgery in all types of valve disease. In aortic stenosis the mortality rises soon after the onset of exertional breathlessness or chest tightness. Exercise testing is an extension of the history and may reveal symptoms in apparently asymptomatic patients. This article discusses the history, examination and exercise testing in patients either newly referred or under routine follow-up in a specialist valve clinic.

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John B Chambers

This is a practical description of how replacement valves are assessed using echocardiography. Normal transthoracic appearances including normal variants are described. The problem of differentiating normal function, patient–prosthesis mismatch and pathological obstruction in aortic replacement valves with high gradients is discussed. Obstruction and abnormal regurgitation is described for valves in the aortic, mitral and right-sided positions and when to use echocardiography in suspected infective endocarditis. The roles of transoesophageal and stress echocardiography are described and finally when other imaging techniques may be useful.

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John B Chambers and Richard P Steeds

As heart valve disease increases in prevalence in an ageing population, comorbidities make patients increasingly hard to assess. Specialist competencies are therefore increasingly important to deliver best practice in a specialist valve clinic, and to make best advantage of advances in percutaneous and surgical interventions. However, patient care is not improved unless all disciplines have specialist valve competencies, and there is little guidance about the practical details of running a specialist valve clinic. In this issue of Echo Research and Practice, the British Heart Valve Society (BHVS) and the British Society of Echocardiography (BSE) introduce a series of articles to guide all disciplines in how to run a valve clinic.

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Nikhil Ahluwalia, Sanjeev Bhattacharyya, Christopher Munns and John Chambers

Transoesophageal echocardiography (TOE) can be used to expedite DC cardioversion (DCCV) in the absence of adequate anticoagulation. There are no guidelines for the management of sedation or general anaesthetic. We performed a survey of NHS echocardiography departments to determine UK practice. Responses were received from 95 (50%) of 189 centres, and TOE-guided DCCV was performed in 81 centres. The numbers were <10 a year in 41 (50%), 10 – 50 in 31 (38%), 50 – 100 in 8 (10%) and >100 in 4 (5%) centres. Sedation for TOE was a usual practice in 67 (80%) centres but often temporally disconnected from DCCV due to logistical reasons. TOE under general anaesthetic was performed in 35 (43%) centres and as the usual method in 16 (20%). The patient was in the supine position with endotracheal intubation in 20 (57%) of centres, but without any form of airway protection while supine in 5 (14%). There is variability in practice across centres in the UK, in part due to limitations to services in most centres but also because of an absence of UK guidelines. The development of national standards may address this and aid in the development of local business cases to extend services.

Open access

Kelly Victor, Michael M Sabetai and John B Chambers

This case report highlights the utility of paravertebral (PV) imaging in the diagnosis of aortic dissection, the evaluation of left ventricular systolic function and drawing the distinction between pleural and pericardial effusions. In this case, less attenuation of the ultrasound beam, reduced lung viscosity due to pleural effusions and less impedance mismatch between media led to images of superior quality and high diagnostic value. This supports the use of paravertebral imaging as an adjunct to conventional echocardiography windows, particularly when conventional transthoracic imaging proves challenging.

Learning points:

  • PV images provide superior resolution when interrogating the descending aorta and thus can reveal incidental findings such as aortic dissection.

  • PV imaging provides clearer delineation between pericardial and pleural effusions.

  • Additional information may be obtained from the PV window in relation to left ventricular systolic function particularly in the setting of suboptimal transthoracic image quality.

Open access

Jenna Smith, Sarah Waters, Brian Campbell and John Chambers

Open access

John B Chambers, Denise Parkin, James Roxburgh, Vinayak Bapat and Christopher Young

Abstract

Aim

To compare the classical and simplified form of the continuity equation in small Trifecta valves.

Methods

This is a retrospective analysis of post-operative echocardiograms performed for clinical reasons after implantation of Trifecta bioprosthetic valves.

Results

There were 60 patients aged 74 (range 38–89) years. For the valves of size 19, 21 and 23mm, the mean gradient was 11.3, 10.7 and 9.7mmHg, respectively. The effective orifice areas by the classical form of the continuity equation were 1.4, 1.7 and 1.9cm2, respectively. There was a good correlation between the two forms of the continuity equation, but they were significantly different using a t-test (P<0.00001). Results using the classical form were a mean 0.11 (s.d. 0.18)cm2 larger than those using the simple formula.

Conclusion

Haemodynamic function of the Trifecta valve in the small aortic root is good. There are significant differences between the classical and simplified forms of the continuity equation.

Open access

Richard P Steeds, Craig E Stiles, Vishal Sharma, John B Chambers, Guy Lloyd and William Drake

This is a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology on the role of echocardiography in monitoring patients receiving dopamine agonist (DA) therapy for hyperprolactinaemia. (1) Evidence that DA pharmacotherapy causes abnormal valve morphology and dysfunction at doses used in the management of hyperprolactinaemia is extremely limited. Evidence of clinically significant valve pathology is absent, except for isolated case reports around which questions remain. (2) Attributing change in degree of valvular regurgitation, especially in mild and moderate tricuspid regurgitation, to adverse effects of DA in hyperprolactinaemia should be avoided if there are no associated pathological changes in leaflet thickness, restriction or retraction. It must be noted that even where morphological change in leaflet structure and function may be suspected, grading is semi-quantitative on echocardiography and may vary between different machines, ultrasound settings and operators. (3) Decisions regarding discontinuation of medication should only be made after review of serial imaging by an echocardiographer experienced in analysing drug-induced valvulopathy or carcinoid heart disease. (4) A standard transthoracic echocardiogram should be performed before a patient starts DA therapy for hyperprolactinaemia. Repeat transthoracic echocardiography should then be performed at 5 years after starting cabergoline in patients taking a total weekly dose less than or equal to 2 mg. If there has been no change on the 5-year scan, repeat echocardiography could continue at 5-yearly intervals. If a patient is taking more than a total weekly dose of 2 mg, then annual echocardiography is recommended.

Open access

John B Chambers, Madalina Garbi, Norman Briffa, Vishal Sharma and Richard P Steeds

Echocardiography plays a vital role in the follow-up of patients with replacement heart valves. However, there is considerable variation in international guidelines regarding the recommended time points after implantation at which routine echocardiography should be performed. The purpose of routine echocardiography is to detect early structural valve deterioration in biological valves to improve the timing of redo interventions. However, the risk of valve deterioration depends on many valve-related factors (valve design and patient prosthesis mismatch) and patient-related factors (age, diabetes, systemic hypertension, renal dysfunction and smoking). In this statement, the British Heart Valve Society and the British Society of Echocardiography suggest practical guidance. A plan should be made soon after implantation, but this may need to be modified for individual patients and as circumstances change. It is important that patients are managed in a multidisciplinary valve clinic.