A New Percutaneous Approach to Treat Combined Right Ventricular and Respiratory Failure: The "Aachen Cannula".

INTRODUCTION: Right ventricular failure (RVF) on its own is a life-threatening condition. Often it manifests as a two-organ failure in the final phase of several lung diseases. Mechanical circulatory support is a proven treatment of RVF but remains challenging. Our objective is to develop a novel, simplified, and minimally invasive cannula approach to treat both RVF and respiratory failure. METHODS: We conceptualized a dual lumen cannula approach to allow oxygenated right-to-left shunting at an atrial level to decompress right-sided circulation. A minimally invasive approach through percutaneous, transjugular insertion and transseptal placement should enable patients to be non-sedated and even ambulatory. In an iterative design, pre-prototyping, prototyping, and anatomic fitting process, such a cannula was generated and tested in both cadaveric and fluid dynamic studies. RESULTS: After various modifications and improvements, a 27-Fr 255-mm-long double-lumen cannula with an inner line (oxygenated blood return to patient into the left atrium) of 18 Fr and an inflatable balloon (with a volume of approximately 1 mL) at the outflow tip was produced - one version with a straight head and another one with a curved head. In our anatomic studies, the "Aachen Cannula" allowed an easy transjugular introduction and advancement into the right atrium by Seldinger technique. Transseptal placement was achieved by puncture (Brockenbrough needle) in combination with dilatation and was then secured in place with the stabilizing balloon, even under slight tension. The cannula prototype enabled a flow of up to 3.5 L/min, at which common pressure drops were observed. CONCLUSION: In conclusion, we successfully conceptualized, designed, and verified a minimally invasive one-cannula approach for the treatment of either isolated right heart failure and even combined RVF and respiratory failure through our transseptal Aachen Cannula. This concept may also be carried out in ambulatory conditions. Moreover, this approach completely avoids recirculation issues and ensures reliable oxygenated coronary as well as cerebral perfusion.

Performance of the Labcor Dokimos Plus pericardial aortic prosthesis: a single-centre experience.

Objectives: In patients with a small aortic annulus, aortic valve replacement (AVR) is frequently associated with high residual pressure gradients. Supra-annular pericardial aortic prostheses are gaining popularity due to the increased effective orifice areas (EOA) and resulting lower gradients. This study reports the clinical and echocardiographic results following implantation of the new supra-annular pericardial aortic prosthesis Dokimos Plus (Labcor, Belo Horizonte, Brazil). Methods: Between October 2013 and July 2015, 137 patients (41% women, mean age: 74 years) underwent supra-annular AVR with or without concomitant procedures using the Dokimos Plus prosthesis in our department. Transthoracic echocardiography was performed pre- and postoperatively on all patients to assess haemodynamic parameters (gradients, acceleration time [AT], Doppler velocity indices [DVIs] and indexed EOA [EOAI]) and to detect paravalvular leakage (PVL). Data were collected retrospectively from our hospital databases. Methods: Patients were grouped by prosthesis size: Most patients received 23-mm (57.6%), followed by 21-mm (19%), 25-mm (15.4%) and 27-mm (8%) prostheses. The mean EOAI in all groups was 1.1 ± 0.26 cm 2 /m 2 . Pressure gradients were low in all groups (mean: 8.9 ± 4.4 mmHg; peak: 18.8 ± 6.8 mmHg); AT and DVI were in the normal range according to American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations (mean AT 73.3 ± 29 ms; mean DVI 0.5 ± 0.2). One patient had severe PVL and one presented with central regurgitation, both requiring re-intervention. The mortality rate was 5.1% ( n = 7); none of the cases was associated with valve insufficiency. Conclusions: The Dokimos prosthesis showed a satisfactory overall performance, presenting low gradients and DVIs as well as high EOAI. Further investigations are needed to analyse the cases of regurgitation and monitor long-term performance.