".... namely that complete removal of the calcium from the circumferential base or ring, that is the annulus, so as to provide an uncalcified base of tissue onto which the prosthesis could be sutured, proved impossible without threatening the integrity of the structures. More particularly, in simple language, to have gone further would have caused a hole in the heart between the left and right ventricles which more than likely would have been an irreparable, fatal condition.
In the result, what must be accepted as a less than ideal process was then followed to secure the prosthesis, namely its placement upon an area from which all the calcium had not been completely removed, again using mattress sutures in an endeavour to buttress the sutures.
To return to the description in the suture placement document:
'Thus for suture purchase and security of valve placement, everting mattress sutures encompassing the area of this residual calcification were placed. This unavoidable situation necessarily involved the compression and distortion of the calcified tissue during suture tying, and gave rise to a fear of dislodgment of calcium. An inspection was carried out through the valve at the completion of tying down, but exposure was typically less than ideal, although no sign of calcium particles could be observed. The ventricle, now full of blood, was up-ended and emptied across the valve to try and flush out any residual particles prior to closing the aortotomy. In the circumstances, the suture placement and tying down of the valve had the potential to create compression and distortion of the calcified tissue in and around the area of the sutures creating the potential for calcific imbolization once the heart became active again.'
Despite these difficulties, the valve was placed correctly and properly seated, with the result that no para-valvular leak has since occurred. By all accounts the plaintiff's valve function by the medium of the prosthesis has been excellent.
However, soon after the operation it was apparent that the plaintiff had suffered a stroke resulting in left sided hemiplaegia.
The stroke was consistent with a blockage in an artery in the right side of the brain. I find that the most likely cause of the blockage in the artery in the brain was the accidental release into the blood stream of a fragment of calcium dislodged from the operation site, which embolised when heart function was restored.
There are three possible means by which a fragment of calcium might have been dislodged from the operation site in circumstances which could have resulted in that consequence:
(a) calcium may have been dislodged and fallen into the left ventricle during the process of removal of the leaflets;
(b) calcium may have been dislodged and fallen into the left ventricle during the process of debridement which followed removal of the leaflets;
(c) calcium may have been dislodged by the process of 'compression and distortion of the calcified tissue in and around the area of the sutures' after the operation site had been closed and the heart re-started.
On the evidence, it is simply not possible to say which of those three possible causes accounts for the calcific embolization which resulted in the damage to the brain."