Sutureless Aortic Valve Implantation through an Upper V-Type Ministernotomy: An Innovative Approach in High-Risk Patients

Minimally invasive aortic valve replacement in high risk patient groups

Minimally invasive aortic valve replacement (AVR) aims to preserve the sternal integrity and improve postoperative outcomes. In low risk patients, this technique can be achieved with comparable mortality to the conventional approach and there is evidence of possible reduction in intensive care and hospital length of stay, transfusion requirement, renal dysfunction, improved respiratory function and increased patient satisfaction. In this review, we aim to asses if these benefits can be transferred to the high risk patient groups. We therefore, discuss the available evidence for the following high risk groups: elderly patients, re-operative surgery, poor lung function, pulmonary hypertension, obesity, concomitant procedures and high risk score cohorts.

Sutureless aortic bioprosthesis valve implantation and bicuspid valve anatomy: an unsolved dilemma?

Interest is growing in the clinical use of sutureless (SU) valves. However, indications in some anatomical sub-settings, like bicuspid aortic valves (BAV), have been so far limited. We discuss herein our initial experience with the implantation of the 3f Enable SU bioprosthesis in patients with a BAV. Patients with a BAV were selected in our unit between March 2011 and September 2014 for a SU 3f Enable valve implantation. Twenty of the 198 patients who underwent a 3f Enable valve implantation in our unit had a BAV. Procedural success was 100 %, but reclamping was necessary in one (5 %) case. Median size of implanted bioprosthesis was 23 mm. After a mean follow-up of 13.8 ± 10.7 months, survival was 100 %. Two patients (10 %) showed an immediate grade 1 paravalvular leak (PVL) that progressed to grade 2 and 3+ (moderate/severe), respectively, during follow-up. Type of bicuspidy (Sievers classification) in these two patients was 0 and intraoperatively aortic annuli admitted the 25 mm calibrator. Among the 18 patients without PVL, no one had a type 0 large BAV. At 1 year, implantation of the 3f Enable SU bioprosthesis appears to be safe in patients with BAV type I and II, while in type 0 use of the SU valve seems to be safe only if the annular diameter is <25 mm. Larger studies are necessary to confirm our findings in order to clarify the indications for SU technology in the subset of bicuspid patients.

Closed chest human aortic valve removal and replacement: Technical feasibility and one year follow-up

BACKGROUND

Minimally invasive aortic valve replacement has so far required a minithoracotomy or a ministernotomy. We present here the first series of totally endoscopic aortic valve replacement (TEAVR).

METHODS

Between June 2013 and April 2015, 14 consecutive patients (12 males, mean age=76 ± 5.4 years) with a mean EuroSCORE II of 2.72 ± 0.03% underwent TEAVR. A five trocar setting was used in all patients: after ablation of the native valve, a Nitinol stented sutureless 3f Enable Medtronic valve, compressed into the main working trocar, was introduced into the thorax and then expanded in the aortic root.

RESULTS

Among the 14 patients, a thoracoscopic approach was successful in 13 (92.8%) and conversion into an open surgery using the right anterior minithoracotomy was necessary to close the aortotomy in one case. Mean cross-clamping and cardiopulmonary (CPB) times were 112 ± 18 and 161 ± 31 min, respectively. All patients left the surgical unit within 8 days after the operation without any paravalvular leakage. There was no paravalvular regurgitation, conductive block or any major adverse event at a mean follow-up of 10 ± 4 months (range 2-16).

CONCLUSIONS

TEAVR is feasible and safe in a selected subset of patients. Closed chest surgery has the potential to become the future approach of the isolated aortic valve replacement in low risk patients but further technical refinement and larger studies are necessary to reduce operative durations and enhance reproducibility.

Experimental Study and Early Clinical Application Of a Sutureless Aortic Bioprosthesis

INTRODUCTION

The conventional aortic valve replacement is the treatment of choice for symptomatic severe aortic stenosis. Transcatheter technique is a viable alternative with promising results for inoperable patients. Sutureless bioprostheses have shown benefits in high-risk patients, such as reduction of aortic clamping and cardiopulmonary bypass, decreasing risks and adverse effects.

OBJECTIVE

The objective of this study was to experimentally evaluate the implantation of a novel balloon-expandable aortic valve with sutureless bioprosthesis in sheep and report the early clinical application.

METHODS

The bioprosthesis is made of a metal frame and bovine pericardium leaflets, encapsulated in a catheter. The animals underwent left thoracotomy and the cardiopulmonary bypass was established. The sutureless bioprosthesis was deployed to the aortic valve, with 1/3 of the structure on the left ventricular face. Cardiopulmonary bypass, aortic clamping and deployment times were recorded. Echocardiograms were performed before, during and after the surgery. The bioprosthesis was initially implanted in an 85 year-old patient with aortic stenosis and high risk for conventional surgery, EuroSCORE 40 and multiple comorbidities.

RESULTS

The sutureless bioprosthesis was rapidly deployed (50-170 seconds; average=95 seconds). The aortic clamping time ranged from 6-10 minutes, average of 7 minutes; the mean cardiopulmonary bypass time was 71 minutes. Bioprostheses were properly positioned without perivalvar leak. In the first operated patient the aortic clamp time was 39 minutes and the patient had good postoperative course.

CONCLUSION

The deployment of the sutureless bioprosthesis was safe and effective, thereby representing a new alternative to conventional surgery or transcatheter in moderate- to high-risk patients with severe aortic stenosis.