Letter by Lauten et al Regarding Article, “Interventional Cardiology Perspective of Functional Tricuspid Regurgitation”

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HomeCirculation: Cardiovascular InterventionsVol. 3, No. 3Letter by Lauten et al Regarding Article, “Interventional Cardiology Perspective of Functional Tricuspid Regurgitation” Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBLetter by Lauten et al Regarding Article, “Interventional Cardiology Perspective of Functional Tricuspid Regurgitation” Alexander Lauten, MD, Markus Ferrari, MD and Hans R. Figulla, MD Alexander LautenAlexander Lauten Department of Internal Medicine I (Cardiology, Angiology, Pneumology and Intensive Care) University Heart Center Jena, Germany (Lauten, Ferrari, Figulla) Search for more papers by this author , Markus FerrariMarkus Ferrari Department of Internal Medicine I (Cardiology, Angiology, Pneumology and Intensive Care) University Heart Center Jena, Germany (Lauten, Ferrari, Figulla) Search for more papers by this author and Hans R. FigullaHans R. Figulla Department of Internal Medicine I (Cardiology, Angiology, Pneumology and Intensive Care) University Heart Center Jena, Germany (Lauten, Ferrari, Figulla) Search for more papers by this author Originally published1 Jun 2010https://doi.org/10.1161/CIRCINTERVENTIONS.110.944926Circulation: Cardiovascular Interventions. 2010;3:e10To the Editor:In their recent article, Agarwal et al1 discuss the current perspective for interventional treatment of tricuspid regurgitation (TR). As stated by the authors, this disease is frequently encountered in patients with left heart valvular disease and substantially contributes to mortality. Because surgical repair or replacement of the tricuspid valve is associated with an excessive operative mortality, there is a vast unmet need for percutaneous techniques.The tricuspid annulus is a complex and highly dynamic structure that offers little resistance for orthotopic long-term fixation of valves with the current technique. As demonstrated by Boudjemline et al,2 orthotopic valve replacement is possible but carries a risk of injury and paravalvular leakage. The vicinity to the endocardium is likely to contribute to ventricular arrhythmia. Similar to percutaneous mitral valve replacement, unique challenges have to be overcome to facilitate orthotopic percutaneous tricuspid valve replacement.In their article, Agarwal et al also relate to the concept of valve implantation into the caval veins as a potential interventional approach to TR. We experimentally investigated this approach, demonstrating feasibility and hemodynamic function of heterotopic valves.3,4 Unpublished data even demonstrate caval valve function up to 3 months after implantation. As stated previously, this concept has several obvious advantages, including the straightforward implantation technique owing to the distance to vulnerable cardiac structures and making this an attractive approach to the interventional cardiologist. The concept could even be simplified further by single valve implantation into the inferior vena cava, because the deleterious effects of TR in humans primarily result from venous congestion to the lower body.However, there are also limitations that have to be considered when transferring this to human patients. Caval valve implantation addresses the regurgitation of blood in the caval veins, which is not found in every patient with TR. Especially in chronic TR with right atrial and ventricular enlargement, the right atrium functions as a reservoir, reducing the prominence of the ventricular wave and limiting the backflow of blood to the caval veins in any degree of TR. Because pulsatile blood flow, however, is a prerequisite for the caval valve to function, hemodynamic proof of regurgitation is required before implantation. Therefore, caval valve implantation will function and have an effect only in patients with severe TR and preserved right ventricular function. The significance of preserved right ventricular function is already known to affect the outcome after tricuspid valve surgery and should—to a different degree—also be taken into account in interventional tricuspid valve replacement.Furthermore, we have to be aware of anatomic differences when transferring caval valve implantation from preclinical studies to human application. Apart from the inflow of the hepatic veins being close to the right atrium in the human inferior vena cava, there is also a considerable variation of the anatomic diameter in patients with severe TR, reaching up to 45 mm in isolated cases. These require a specific, potentially individual solution for percutaneous device implantation.In summary, although percutaneous valve implantation into the caval veins may seem straightforward and simple, this approach still poses the earlier mentioned challenges and probably several more yet unknown. We believe these challenges to be surmountable, but this approach will likely be limited to the most severely ill group of patients with TR.Alexander Lauten, MDMarkus Ferrari, MDHans R. Figulla, MD Department of Internal Medicine I (Cardiology, Angiology, Pneumology and Intensive Care) University Heart Center Jena, GermanyDisclosuresNone.