As the field of structural heart interventions expands from the now-established transcatheter therapies for native aortic stenosis to include treatment of mitral and tricuspid valve disease, there is growing interest in imaging evaluation of the atrioventricular valves. Rebecca T Hahn, in this commentary, explores the state-of-the-art imaging techniques for these valves and reviews what recent guidelines recommend in this area.
Mitral and tricuspid regurgitation, compared with aortic regurgitation, are significantly more complex in their aetiology and morphology, as well as in their evidence-based management options. The first step in the evaluation of these valvular abnormalities is imaging.
Both the updated guidelines of American College of Cardiology (ACC)/American Heart Association (AHA) and those of the European Society of Cardiology/European Association of Cardio-Thoracic Surgery (EACTS) for valvular heart disease1,2 agree that echocardiography is the imaging modality of choice (Class I) for the evaluation of mitral disease.
The primary goals of imaging for mitral regurgitation are to assess disease morphology and severity, as well as the effects of regurgitation on chamber size and function as well as pulmonary artery pressures. Although prognosis is driven by even mild regurgitation for secondary disease,3 severe regurgitation drives outcomes in degenerative disease.4,5 Prior iterations of guidelines classified severity of disease based on prognosis related to different morphologies6,7, however, both the ACC/AHA guidelines and the updated American Society of Echocardiography (ASE) native valvular regurgitation guidelines8 now advocate using one grading scheme for severity of either primary or secondary regurgitation.
Despite the growing commercial use of the transcatheter leaflet repair devices, only the updated ESC/EACTS guidelines give indications for use of this treatment option.2 However, numerous other transcatheter repair or replacement devices are currently under investigation will require preprocedural imaging with computed tomography and intraprocedural guidance from transoesophageal echocardiography.
Although natural history studies have suggested that tricuspid regurgitation (70–80% being secondary) is associated with poor outcomes,9,10 the ACC/AHA recommendations regarding tricuspid regurgitation have not changed significantly over the last decade.1 Similar to their recommendations for mitral regurgitation, the guidelines advise separate treatment algorithms based on morphology and recommend echocardiographic imaging as the first-line modality. The updated ASE guidelines also have not changed significantly in the assessment of regurgitant severity.8 Because of the limited indications for surgical intervention in this disease, transcatheter therapies have developed rapidly over the last three years.11–14
What we have learned from studies of tricuspid regurgitation is that symptomatic patients present with regurgitant orifices over one square centimetre and the conventional grading schemes of “mild, moderate and severe” cannot accurately describe this severity of disease. Novel echocardiographic quantitative methods described in these trials11 were used to support a proposal for an extended grading scheme including grades beyond severe: massive and torrential.15 As outcomes data are gathered using this new grading scheme, the benefits of transcatheter device therapy may be forthcoming. Just as with mitral interventions, multimodality imaging will play a key role in the diagnosis and management of this disease.
- Nishimura et al. Circulation 2017. Epub.
- Baumgartner et al. Eur Heart J 2017 In press.
- Sannino et al. JAMA Cardiology 2017. Epub.
- Grigioni et al. JACC Cardiovasc Imaging 2008; 1:133–41.
- Suri et al. JAMA 2013; 310: 609-16.
- Nishimura et al. J Am Coll Cardiol 2014; 63: 2438–88.
- Vahanian et al. Eur J Cardiothorac Surg 2012; 42: S1–44.
- Zoghbi et al. J Am Soc Echocardiogr 2017; 30: 303–71.
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- Goldstone et al. J Thorac Cardiovasc Surg 2014; 148: 2802–09.
- Hahn et al. J Am Coll Cardiol 2017; 69: 1795–1806.
- Nickenig et al. Circulation 2017; 135: 1802–14.
- Campelo-Parada et al. J Am Coll Cardiol 2015; 66:
- Bardeleben et al. Eur Heart J 2017; 38: 690.
- Hahn et al. European Heart Journal Cardiovascular Imaging 2017.
Rebecca T Hahn is at Columbia University Medical Center/NY Presbyterian Hospital (New York, NUSA). She spoke about this topic at PCR London Valves (24–26 September, London, UK).