<div>Commentary on: Tissue “valve-over-valve” implantation in previous
mechanical Bentall</div><div>Mohammed Farouk Hassan, MD MBA <sup>1</sup></div><div><sup>1</sup>Department of Surgery, Baylor Scott &amp; White, Temple
TX</div><div>Word Count: 472</div><div>Key Words: valve repair/replacement</div><div>Corresponding Author:</div><div>Mohammed F. Hassan, MD FACS MBA</div><div>Associate Professor, Texas A&amp;M University HSC COM</div><div>Baylor Scott &amp; White Health</div><div>Division of Cardiothoracic Surgery</div><div>Department of Surgery</div><div>Temple, TX</div><div>mhassanct@gmail.com</div><div>Cell 513-460-3499</div><div>Abstract:</div><div>The authors present a case report about elective replacement of a
mechanical Bentall with a bioprosthetic valve. The authors describe a
technique whereby the mechanical valve is ’broken’ off its mechanism and
the new valve is sutured in the old cuff.</div><div>In the recently submitted case report by Okiwelu and colleagues, the
authors describe a challenging case of a young patient who underwent a
Bentall procedure using a 31mm ATS mechanical valve conduit (Medtronic,
Minneapolis, MN) who then requested re-replacement with a bioprosthetic
valve because of the impact of the audible clicks from the mechanical
valve on his quality of life. The authors describe a technique whereby
the mechanical valve was ’broken’ off its mechanism and the new valve
(29mm Edwards Inspiris Resilia, Edwards, Irvine, CA) was sutured to the
sewing cushion of the carbon housing.</div><div>This is an interesting approach but raises some questions and points to
consider. The low profile of the supra-annular portion of the ATS made
it possible for this approach. The other mechanical valves being used
currently have a supra-annular component that would prohibit such an
approach.</div><div>With the approach described, the carbon housing of the valve was left
behind. This is a 45-year-old patient who will need two or more aortic
interventions in the future if he remains with the bioprosthetic option.
The ‘housing’ left behind will limit the use of future TAVRs especially
if there is pannus formation within the housing.</div><div>Despite using precautions while fracturing the valve, it is difficult to
have full control of the carbon components with blunt fracture and, as
the authors mention, increase the risk of a neurologic complication.
This patient did have a neurologic complication of mild left eyelid
droop with meiosis despite having a negative MRI exam.</div><div>In addition, the technique of breaking off the leaflets, causes damage
to the general lining of the remaining ‘housing’ and damages the carbon
surface which could serve as a nidus for thrombus formation as described
by the FDA’s summary of safety and effectiveness data. This would argue
that the patient in this case may benefit from long term
anti-coagulation. <sup>1,2</sup></div><div>Even though it involves a more involved surgery, was a full redo
bio-Bentall considered given the age of the patient. Also, was a Ross
procedure considered for this patient? Mazine and colleagues carried out
a meta-analysis comparing the Ross procedure with mechanical aortic
valve replacement and concluded that there was lower all-cause mortality
compared with mechanical aortic valve replacement.<sup>3</sup></div><div>References</div><div>1. Gott V.L., Alejo D.E., Cameron D.E. Mechanical heart valves: 50 years
of evolution. Ann. Thorac. Surg. 2003;76:S2230–S2239.</div><div>2. FDA. ATS Open Pivot Bileaflet Heart Valve: Instructions for use.
2000. Maryland, USA.</div><div>3. Mazine A, Rocha RV, El-Hamamsy I, et al. Ross Procedure vs Mechanical
Aortic Valve Replacement in Adults: A Systematic Review and
Meta-analysis. <i>JAMA Cardiol</i> . 2018;3(10):978-987.
doi:10.1001/jamacardio.2018.2946</div>