This content is only for readers outside of the US as it discusses a device that is not FDA approved.
The granting of the CE mark to Edwards Lifesciences for its Cardioband Tricuspid System was an important development for patients with tricuspid regurgitation.1 As well as becoming the first—and only—approved percutaneous treatment option for tricuspid repair on the European market, the device represents a new option for a condition that historically has been under-treated because, at least in part, the number of suitable treatments are limited.
in the USA, 1.6 million people have moderate-to-severe tricuspid regurgitation and most of them have functional tricuspid regurgitation.2 According to Dr. Stephan von Bardeleben (Heart Valve Center Mainz—Cardiology I, University Medicine Mainz, Mainz, Germany), 80% of his patients have functional tricuspid regurgitation, and he explains that “functional means secondary to left heart disease, both ventricular and valvular in origin, or secondary to any pressure load such as lung disease”.
However, despite its relatively high prevalence, tricuspid regurgitation has historically been under-diagnosed and under-treated. Dr. von Bardeleben reports that less than 1% of patients with moderate-to-severe tricuspid regurgitation will undergo surgical or interventional repair this year, which supports similar statistics reported in American studies.3 In contrast, tricuspid regurgitation is more prevalent than aortic stenosis, yet 15–20% of patients with aortic stenosis will receive adequate (surgical or transcatheter) therapy this year, he notes. “The number of patients with moderate-to-severe tricuspid regurgitation receiving adequate treatment differs from country to country, with much greater under-treatment in developing countries such as India,” Dr. von Bardeleben observes.
One of the reasons why a relatively small percentage of patients with tricuspid regurgitation receive treatment is the misconception that tricuspid regurgitation does not require treatment; this has led to the under-recognition of the clinical impact of tricuspid regurgitation on morbidity and mortality. In fact, tricuspid regurgitation is both a significant marker and cause of increased mortality.4 The increased risk of mortality correlates to the severity of tricuspid regurgitation. Dr. von Bardeleben states, “Patients with severe tricuspid regurgitation have the worst prognosis, with the survival rate being less than 50% by five years.” He adds that patients “complain about an inability to exercise, experience fatigue, have liver dysfunction, and have leg oedema,” meaning that their quality of life “is severely impaired”.
Treatment of tricuspid regurgitation, provided it is successful and performed early enough, can improve cardiac output, decrease venous pressure, and improve leg oedema among other benefits. However, a key issue—and the main reason for the under-treatment of patients with tricuspid regurgitation—is a lack of available therapeutic options. While isolated surgery can be used for some patients, according to Dr. von Bardeleben, it is associated with substantial in-hospital mortality (8–10%).5 The only non-surgical option—prior to the Cardioband tricuspid system receiving the CE mark—was palliative medical therapy with diuretics. Therefore, there is a definite need for a less invasive therapeutic option in patients with this condition.
The Cardioband tricuspid system has been designed to address this need. Dr. von Bardeleben explains that it reduces the septolateral, as well as the anterior-posterior, diameter of the tricuspid valve. Although a similar device is used to treat mitral regurgitation (Cardioband Mitral System, Edwards Lifesciences), there are different considerations when treating patients with tricuspid regurgitation. He comments, “The stiffness of the tricuspid annulus is less than that in the mitral space. The proximity of the right coronary artery—as well as the limited thickness of the basal right ventricular wall—has to be respected when using the system in the tricuspid valve. In the mitral space, the circumflex artery is the artery with the closest relation to the Cardioband anchors.”
So far, data for the Cardioband tricuspid system shows that it is a reasonable option for managing tricuspid regurgitation. The TRI-REPAIR study was a single-arm, prospective, study in which 30 patients with functional tricuspid regurgitation received the Cardioband tricuspid system.6 The primary endpoint was the rate of major serious adverse events at hospital discharge and at 30 days (safety endpoint) and the successful access, deployment, and positioning of the device (technical success endpoint). Other endpoints included reduction in tricuspid regurgitation grade, effective regurgitant orifice area (EROA), and volume and functional tests.
Technical success was achieved in all patients and, overall, there was a 16% reduction in septolateral diameter at discharge: 37±4.5mm vs. 44.4±4.4mm at baseline (paired t-test p<0.001). This reduction was sustained at 30 days and at six months. Furthermore, at 30 days, there was a 51% reduction in EROA, 31% reduction in vena contracta, and a 9% improvement in left ventricular stroke volume. These results were again sustained at six months (interim report).
In terms of functional improvements, at 30 days, there were significant improvements in Kansas City Cardiomyopathy Questionnaire scores (p<0.01), New York Heart Failure Association (NYHA) class (p<0.01), and oedema (p=0.01). By six months (interim report), not only were these improvements sustained but there was also a significant improvement in the six-minute walk test compared with baseline levels.
Presenting the data at EuroPCR 2018 (21–24 May, Paris, France), Prof. Francesco Maisano (Heart Valve Clinic, University Hospital of Zurich, University of Zurich, Zurich, Switzerland) said: “In an early experience, the Cardioband tricuspid system provides a significant reduction in EROA through annular reduction,” adding that the study had given “valuable learnings”.
For Dr. von Bardeleben, the key to achieving good outcomes with the system is “optimal patient selection”. Therefore, he thinks that the patients who will benefit the most are those with annular septolateral dilatation that is intermediate (4–5cm), rather than severe, and those with moderately impaired, right ventricular function. He adds: “Patients should have NYHA Class II or III with symptoms but still have residual ability to walk so that they can be mobilised after the procedure.” Dr. von Bardeleben also believes that patients, prior to the procedure, should also have a life expectancy of more than one year and systolic pulmonary artery pressures of less than 60mmHg.
Summing up the available evidence for the Cardioband tricuspid system, alongside what is known about the optimal management of patients with tricuspid regurgitation, Dr. von Bardeleben says that the system is “the beginning of a new ‘microinvasive’ generation of transcatheter tools to address both “a forgotten valve and forgotten patient population”. He adds: “The Cardioband system has shown feasibility and safety, but there still is a journey of learning and understanding as well as sub differentiating the haemodynamics and pathophysiology of tricuspid and right heart disease. At the Heart Valve Center Mainz, we are happy and proud to be part of this journey.”
- BIBA Medical staff. Cardioband becomes first-ever transcatheter tricuspid system to receive the CE mark. Cardiovascular News 2018. https://bit.ly/2u6C5os (date accessed 10 July 2018)
- Stuge O, Liddicoat J. Journal of Thoracic and Cardiovascular Surgery 2006;132 (6):1258-61
- McCarthy PM, Sales VL. Current Treatment Options in Cardiovascular Medicine 2010; 12(6): 587–97.
- Nath J, Foster E, Heidenreich PA, et al. Impact of tricuspid regurgitation on long-term survival JACC 2004; b43(3):405–09.
- Fender EA, Zack CJ, Nishimura RA. Isolated tricuspid regurgitation: outcomes and therapeutic interventions. Heart 2018; 1; 104 (10): 798–806.
- Maisano. EuroPCR 2018.