Valvular heart disease: new evidence and updated guidelines

My Post (14)Following new evidence in recent years, updated guidelines have been published for the management of valvular heart disease (VHD) by the European Society of Cardiology (ESC) and European Association for Cardio-Thoracic Surgery (EACTS). Since the last iteration of the Guidelines, randomised trials on percutaneous interventional techniques and risk-stratification regarding timing of intervention in VHD have made new recommendations necessary. Following new evidence in recent years, updated guidelines have been published for the management of valvular heart disease (VHD) by the European Society of Cardiology (ESC) and European Association for Cardio-Thoracic Surgery (EACTS). Since the last iteration of the Guidelines, randomised trials on percutaneous interventional techniques and risk-stratification regarding timing of intervention in VHD have made new recommendations necessary.

ESC Chairperson, Professor Helmut Baumgartner said:

‘Since the 2012 Guidelines, a large amount of new data have accumulated, particularly in the field of catheter interventional treatment of valvular heart disease.’

Valvular heart disease

VHD is a leading cause of morbidity and mortality worldwide, and refers to conditions where the heart’s valves do not work properly (British Heart Foundation (BHF), 2017). This in turn can affect flow of blood to the heart. The estimated prevalence of VHD in developed countries is 2.5% (Lung and Vahanian, 2014). Causes of VHD can be congenital or acquired, with prevalence increasing markedly in those over 65 years of age (Lung and Vahanian, 2017).

Valve stenosis, or narrowing, refers to a valve that does not open fully, which will obstruct or restrict the flow of blood (BHF, 2017). As the heart has to pump harder in order to force the blood past the narrowing, it can put extra strain on the heart (BHF, 2017). By contrast, valve regurgitation, or leaky valve, concerns a valve that is not able to close properly, and so will allow blood to leak backwards (BHF, 2017). Again, this can put strain on the heart, but this is because the heart has to work harder to pump the required volume of blood (BHF, 2017). While many people may not experience any noticeable physical effects, commonly reported symptoms include:

  • Breathlessness
  • Swelling of the ankles and feet
  • Fatigue (BHF, 2017).

Echocardiography

As was discussed in a recent issue of the British Journal of Cardiac Nursing, echocardiography is the gold standard to confirm a diagnosis of VHD, as well as to assess its severity and prognosis (Hall, 2017). It is also key to assess valve morphology and function, as well as to evalu¬ate the feasibility and indications of a specific intervention. Aortic stenosis is the most common VHD, leading to surgery or catheter intervention in Europe and the United States (US). Its growing prevalence is attributable to the ageing population. Echocardiography is used to:

  • Confirm the presence of aortic stenosis
  • Assess the degree of valve calcification, left-ventricle function and wall thickness
  • Detect the presence of other associated valve disease or aortic pathology
  • Provide prognostic information.

Baumgartner said:

‘In aortic stenosis, there have been five randomised clinical trials comparing surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI) as well as large-scale registry data.’

The Guidelines strongly recommend early therapy in symptomatic patients with severe aortic stenosis. Exceptions are given to patients with severe comorbidities indicating a survival of less than a year, and patients in whom there are severe comorbidities, or their general condition at an advanced age make it unlikely that the intervention will improve their quality of life or survival.

SAVR and TAVI

SAVR is recommended in patients at low surgical risk, while TAVI is recommended in patients not suitable for surgery. For patients at increased surgical risk, the decision between SAVR and TAVI should be made by the heart team of surgeons and cardiologists, with TAVI being favoured in older patients suitable for transfemoral access.

The Guidelines stress that aortic valve interventions should only be performed in heart valve centres that include both cardiology and cardiac surgery on site. For asymptomatic patients, SAVR is indicated in those with severe aortic stenosis and systolic left-ventricular function not owing to another cause.

Baumgarter noted:

‘There is new evidence regarding predictors of outcome in asymptomatic patients with valvular heart disease and on antithrombotic therapy in this patient population among other innovations. This definitely required an update of management recom¬mendations.’

Baumgartner emphasised that risk score and age are not the only factors affecting the decision to use SAVR or TAVI:

‘The choice of surgical aortic valve replacement or transcatheter aortic valve implantation is not simply based on a risk score or age—the heart team must weigh the risks and benefits of both procedures, particularly in the intermediate risk situation. Discussion should include age, comorbidities, anatomy, and out¬comes of the centre for surgery and transcatheter intervention.’

Risk-stratification

Risk-stratification is an essential means of decision-making in this patient population in order to establish the risk of intervention compared with the expected natural history of VHD. The Guidelines call for the development of better risk-stratification tools, particularly for the decision between surgery and catheter intervention and for the avoidance of futile interventions.

In asymptomatic patients with VHD, studies suggest early surgery may improve outcomes. However, deciding when to intervene is controversial. For example, asymptomatic patients with aortic stenosis, who have pulmonary hypertension have been introduced into the criteria for being selected for surgery, following studies which showed it was a predictor of poor outcomes. But on the other hand, conflicting studies on the prognostic value of exercise echocardiographic parameters indicate the removal of asymptomatic patients with aortic stenosis and mitral regurgitation from the selection criteria.

Recommendations on the use of antithrombotic therapy have also been updated. Antithrombotic management should address effective control of modifiable risk factors for thromboembolism in addition to the prescription of antithrombotic drugs. The Guidelines state that there are now sufficient data to recommend non-vitamin K antagonist oral anticoagulants as an alternative to vitamin K antagonists in patients with atrial fibrillation who have aortic valve disease or mitral regurgitation. They do, however, point out that non-vitamin K antagonist oral anticoagulants remain contraindicated in patients with mechanical valves and in mitral stenosis.

Conclusion

These new Guidelines from ESC and EACTS represent a much-needed update on the management of VHD. They take into consideration new evidence on risk-stratification and the timing of intervention, as well as on percutaneous intervention techniques. They are aimed at both cardiologists and surgeons, and as Professor Volkmar Falk, EACTS Chairperson, highlights, it is important that both specialties follow the recommendations:

‘This is a joint guideline between cardiologists and surgeons. It is absolutely essential that both specialties follow the same recommendations because we are treating the same patients. Decisions in structural valve disease must be taken by a heart team of cardiologists and surgeons.’

References 

Baumgartner H, Falk V, Bax JJ et al. 2017. 2017 ESC/ EACTS Guidelines for the management of valvular heart disease. Eur Heart J. 2017;38(36):2739- 2791. https://doi.org/10.1093/eurheartj/ehx391

British Heart Foundation. Heart valve disease. 2017. http://tinyurl.com/yat7vjzt (accessed 15 December 2017)

Hall A. Suspected mitral valve disease: clinical assessment. Br J Cardiac Nurs. 2017;12(11):538- 546. https://doi.org/10.12968/bjca.2017.12.11.538

Lung B, Vahanian A. Epidemiology of acquired valvular heart disease. Can J Cardiol. 30(9):962-970. https://doi.org/10.1016/j.cjca.2014.03.022

Taken from British Journal of Cardiac Nursing, published December 2017.

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Experts call on NICE to review TAVI guidelines for aortic stenosis

Adobe Spark (5)Leading experts have urged the National Institute for Health and Care Excellence (NICE) to review its guidelines on the use of transcatheter aortic valve implantation (TAVI) for aortic stenosis to include intermediate-risk patients.

Speaking at a plenary session of the PCR–London Valves conference, experts delivered a focused summary of the new European Society of Cardiology (ESC)/European Association for Cardio-Thoracic Surgery (EACTS) guidelines on valvular heart disease (Baumgartner et al, 2017). This included details of how the guidelines have been updated to lower the threshold for intervention with TAVI to patients at intermediate-risk of surgery. Previous guidance stipulated that TAVI should only be considered for those patients with symptomatic aortic stenosis at high risk of surgery (Vahanian et al, 2017).

Dr Helmut Baumgartner, chair of the taskforce for the European Guidelines, has said the new recommendations mark a profound change to the 2012 guidelines. This is largely owing to the number of randomised controlled trials comparing surgical and transcatheter treatments in the last 5 years. These have looked at intermediate- and low-risk patients treat-ed, not just elderly high-risk patients (Leon et al, 2016). He said:

‘There is much controversy right now over who should undergo surgery and who should undergo per-cutaneous valve implantation, and this is an area in which we have profound changes in what we recommend and have consequently dedicated a large part of the guide-lines to the choice of intervention in symptomatic aortic stenosis.

‘We are now recommending that surgical valve replacement remains the first line of therapy in low-risk patients, and low risk should not only be defined by risk scores, because these have several limitations, but by the lack of frailty and other specific risks for surgery not included in risk scores such as porcelain aorta or sequelae of chest radiation. There are numerous issues that need to be considered before we speak of low-risk patients.’

How NICE guidelines differ

An updated version of NICE’s Interventional Procedures Guidelines (IPG), which considers whether procedures are safe and work well enough for wider use in the NHS, was published a month before the ESC/EACTS guidelines (NICE, 2017). At first glance, it appears not to have revised the indication for TAVI beyond the high-risk patient population, unlike the European guidelines. According to a press advisory from Edwards Lifesciences (2017), NICE said additional trials are needed before TAVI could be considered in patients at inter-mediate risk for surgery:

‘Based on current data, TAVI is recommended in patients with severe symptomatic aortic stenosis who are, according to the heart team considered unsuitable for conventional surgery because of severe comorbidities.

Should NICE guidelines change?

Approximately 1.5 million people in the UK over 65 years suffer from heart valve disease with aortic stenosis (d’Arcy et al, 2016). This represents 2–7% of those over 65 years (Spaccarotella et al, 2011) and 13% of those over 75 years (Nkomo et al, 2006). For many cardiologists, it is believed that expanding the use of TAVI would enable more patients in the UK to have access to the minimally-invasive therapy, rather than have to undergo open-heart surgery.

According to Dr Bernard Prendergast, Consultant Cardiologist at Guy’s and St Thomas Hospital and Course Director/Board Member of PCR London Valves, recent evidence increasingly supports the use of TAVI for intermediate-risk patients. Speaking at the PCR–London Valves conference, he said:

‘There is growing evidence in favour of the use of TAVI for the treatment of intermediate-risk patients with severe symptomatic aortic stenosis. This expanded indication in the ESC/EACTS guidelines paves the way for more patients to receive a true alter-native to open-heart surgery.’

As a result, Prendergast emphasised why NICE should update their guidelines to be in line with the rest of Europe:

‘We are calling for NICE to review their recent IPG in light of these new ESC guidelines in order to address current inequalities in treatment across the UK, and between the UK and most of Europe.’

There is concern that the NICE guidelines leave UK patients at a disadvantage in the treatment of aortic stenosis com-pared with the rest of Europe. Currently, the UK performs far fewer aortic valve implantations than Germany, France, Norway and Sweden.

Clearing up misconceptions

It was hoped in light of the new ESC/EACTS guidelines that this disadvantage would change. However, when NICE was asked if they will be looking into revising their guidelines to recommend TAVI for aortic stenosis for intermediate-risk patients for the writing of this article, they clarified that their guidelines have actually already been extended beyond the high-risk population.

In response to the expert calls for revision and the critical comments quoted in this article, a spokesperson from NICE requested a correction, stating:

‘The new guidance gives standard arrangements for TAVI and does not any longer differentiate between different risk groups. The decision as to which patients are suitable is left to risk assessment by clinicians and the MDT [multidisciplinary team].’

References

Baumgartner H, Falk V, Bax JJ et al. 2017 ESC/EACTS Guidelines for the management of valvular heart disease. Eur Heart J. 2017;38(36):2739–2791.

d’Arcy JL, Coffey S, Loudon MA et al. Large-scale community echocardiographic screening reveals a major burden of undiagnosed valvular heart disease in older people: The OxVALVE Population Cohort Study. Eur Heart J. 2016;37(47):3515-3522.

Edwards Lifesciences Ltd. Leading Experts Call for Adoption of New ESC/EACTS Guidelines on the Management of Valvular Heart Disease to include Intermediate-Risk Patients in National Protocols [Press Advisory]. Berkshire: Edwards Lifesciences Ltd.

Leon MB, Smith CR, Mack MJ et al. Transcatheter or surgical aortic-valve replacement in intermediate risk patients. N Engl J Med. 2016;374(17):1609-20.

National Institute for Health and Care Excellence. Transcatheter aortic valve implantation for aortic stenosis. Interventional procedures guidance [IPG586]. London: NICE; 2017.

Nkomo VT, Gardin JM, Skelton TN, Gottdiener JS, Scott CG, Enriquez-Sarano M. Burden of valvular heart disease: a population-based study. Lancet. 2006;368:1005-11.

Spaccarotella C, Mongiardo A, Indolfi C. Pathophysiology of aortic stenosis and approach to treatment with percutaneous valve implantation. Circ J. 2011;75(1):11-19.

Vahanian A, Alfieri O, Andreotti F, et al. Guidelines on the management of valvular heart disease (version 2012). Eur Heart J. 2012;33(19):2451-96.

Taken from British Journal of Cardiac Nursing, published October 2017.