Influence of stentless versus stented valves on ventricular remodeling assessed at 6 months by magnetic resonance imaging and long-term follow-up

An ex vivo evaluation of two different suture techniques for the Ozaki aortic neocuspidization procedure

 

OBJECTIVES

We investigated the Ozaki procedure using a single interrupted suture technique (SST) and compared this with the standard continuous suture technique (CST) with regard to hydrodynamic valve performance. In addition, both techniques were compared with the native aortic valve (NAV).

METHODS

Effective orifice area, mean pressure gradient and leakage volume were evaluated in the NAV as well as after an Ozaki procedure using SST or CST in fresh swine aortic roots using a mock circulation loop. The NAV, SST and CST were evaluated under 4 defined hydrodynamic conditions.

RESULTS

Both suture techniques resulted in a similar effective orifice area under all conditions [for stroke volume of 70 ml: SST: 1.50 (1.35-1.87) vs CST: 1.57 (1.41-1.72) cm2, P = 0.8] and there were no significant differences between both suture techniques and the NAV (P > 0.05). Regarding mean pressure gradient, the Ozaki procedure with SST and CST showed no significant differences [7.23 (5.53-8.91) vs 7.04 (6.65-7.60) mmHg, P = 0.72] and there was no significant difference between both suture techniques and the NAV (P > 0.1). In leakage volume, there was no significant difference between SST and CST [4.49 (3.91-4.99) vs CST: 4.23 (3.58-4.87) ml/stroke, P = 0.34].

CONCLUSIONS

The Ozaki procedure with SST performed similarly to that with CST with regard to hydrodynamic performance. Our results suggest that the Ozaki procedure can be performed with SST instead of CST, which may be useful in patients with limited surgical exposure, such as a small annulus.

Decellularized xenografts in regenerative medicine: From processing to clinical application

Decellularized xenografts are an inherent component of regenerative medicine. Their preserved structure, mechanical integrity and biofunctional composition have well established them in reparative medicine for a diverse range of clinical indications. Nonetheless, their performance is highly influenced by their source (ie species, age, tissue) and processing (ie decellularization, crosslinking, sterilization and preservation), which govern their final characteristics and determine their success or failure for a specific clinical target. In this review, we provide an overview of the different sources and processing methods used in decellularized xenografts fabrication and discuss their effect on the clinical performance of commercially available decellularized xenografts.

Peri-procedural thrombocytopenia after aortic bioprosthesis implant: A systematic review and meta-analysis comparison among conventional, stentless, rapid-deployment, and transcatheter valves

BACKGROUND

Thrombocytopenia has been shown to occur soon after surgical biological aortic valve replacement (AVR), and recently reported also after transcatheter valve implantation (TAVI). The mechanism underlying this phenomenon is still unknown, and its clinical impact on the peri-operative outcome has been poorly investigated.

METHODS

A systematic review and a meta-analysis of all available studies reporting data about peri-procedural thrombocytopenia on isolated bio-AVR, comparing rapid-deployment (RDV), stentless (stentless-AVR), and TAVI vs. stented (stented-AVR) valves, have been performed.

RESULTS

Fifteen trials (2.163 patients) were included in the meta-analysis. Perioperative platelet reduction ranged from 35% to 55% in stented-AVR, from 60% to 77% in stentless-AVR, from 53% to 60% in RDV, and from to 21% to 72% in TAVI (apparently, balloon-expandable valves more frequently associated to thrombocytopenia). Stented-AVR required more red blood cells transfusion than stentless-AVR (P < 0.0001), whereas no difference has been found between RDV and stented-AVR. Platelet transfusion rate was very low in all surgical groups. No difference has been found in RDV and stentless-AVR vs. stented-AVR, in terms of reoperation for bleeding, and length-of-intensive care unit or hospital stay.

CONCLUSIONS

Thrombocytopenia-related major adverse events were mainly reported in TAVI patients, whereas clinically meaningless in surgical patients. Transient peri-procedural thrombocytopenia is common after bio-AVR, regardless of prosthesis's type or implant modality. It should receive appropriate monitoring and focused investigations.