Usage,Tensile Strength And Short Term Outcomes Of A Novel Side Exiting Pledgetted Suture In Mitral Valve Replacement

PurposeSince the start of using prothesis to replace damaged mitral valves,complications can arise due to the inferior aspect of the annular not being visible to the operating surgeon so he or she is unable to see if the pledget is flipped over and consequentely not sitting on the right place was on the subannular surface.We designed a pledget that has its sutures exiting from the short edges of the pledget rather than the flat surface meaning that there is no one right way for it to sit.In other words,it will function the same whichever of its flat surfaces is abutting the subannular surface.We hypothesised that side exiting sutures will not only reduce the risk of dehiscence and suture failure,but also reduce cross clamp time as the surgeon will not need to spend as much time checking that each pledget has not flipped over.Both of these characteristics of the pledgets we have designed with be of benefit to the cardiac surgery patient as they will reduce the amount of complications suffered and the time taken to recover from surgery.This paper looks at the usage in China of our newly designed pledget which has the sutures entering and exiting from the two short edges of the pledget rather than the previously used traditional pledget design where the sutures enter and exit perpendicularly from the base of the pledget.This paper also compares the tensile strength that these pledgets can undergo in comparison to that of traditional pledgets.Finally,the paper will look at operation and cross clamp time,as well as post operative 30 day outcomes of the 469 patients who underwent mitral valve replacement with our novel type of suture.MethodsThis paper documents the number of our novel side exiting pledgetted sutures which have been used across China by year and by province.The novel side sutured pledget and the traditional Ethibond Ti Cron 2-0 pledgeted suture were tested in a tensile strength testing machine for the maximum tensile strength they could withstand before breaking.Between 2016 and 2019 469 patients underwent mitral valve replacement using our novel side exiting pledgetted sutures at Zhejiang University First Affiliated Hospital in Zhejiang,China.The operation and cross clamp time,as well as the 30 day post operative outcomes including time of stay in ICU;number reoperated on for rebleeding;the number of patients requiring implantation of permanent peacemakers;the number of patients suffering from a stroke;those suffering a cerebral vascular accident;mortality and hospital stay were recorded for each of the 469 patients.This will be presented in this paper.Results1.Between 2016 and 2019,84794 of our novel side exiting pledgetted sutures have been used across 8 provinces in China,with most pledgets used in Zhejiang province and the total number of pledgets increasing year on year.Our novel side exiting pledgetted sutures are currently being used in Zhejiang,Beijing,Anhui,Shandong,Shanghai,Sichuan,Shanxi and Jiangxi.Our suture now accounts for around 10% of the sales of sutures for valve replacement in the Chinese market.2.The maximum average force which our novel side exiting pledgetted sutures suture can withstand is 34.61 N ± 2.25 N of force,significantly higher than just the suture from the Ethibond Ti Cron 2-0 pledget suture can withstand an average force of 25.44 N ± 5.03 N.This is primarily due to our suture being wider,at 0.350mm-0.399 mm,than the Ethibond suture at 0.349 mm.However,the larger diameter of our suture is still an acceptable range,which will not affect operative procedures including suturing,knotting and prosthesis implanting.When testing the suture of our novel side exiting pledgetted sutures in combination with the actual pledget,it can withstand an average force of 12.89 N ± 3.39 N.Therefore,the strength our suture comfortably exceeds the national requirements for sutures in China.3.For the 469 patients,with a mean age of 57,that underwent mitral valve replacement in our hospital using our novel side exiting pledgetted sutures.We recorded ICU stay duration,complication rates and mortality over a 30 day period.70% of the patients had mechanical mitral valve prosthesis fitted,so the remaining 30% had biological mitral valve prothesis fitted.54% of the patients underwent a concomitant tricuspid valvuloplasty;3% had the operation combined with coronary artery bypass grafts;12 had an atrial septal defect repair at the same time and 1 of the patients also had extripation of an atrial myoxma at the same time.We found that there was a mortality of 8 in the 30 day period;43 had to be taken back to theatre for bleeding within the same period;3 underwent pacemaker implantation;1 patient suffered from a stroke and 1 had renal failure.The average length of stay on ICU was 72 hours.Conclusion1.An increasing number of patients are undergoing mitral valve replacement using our novel side exiting pledgetted sutures across 8 provinces in China.Currently,our novel suture accounts for around 10 % of the sales of sutures for valve replacement in the Chinese market.2.Our novel side exiting pledgetted sutures are able to withstand a greater forces than Ethibond Ti-Cron sutures in the lab because of the difference in diameter.However the larger diameter of our suture does not affect operative procedures.3.The complication and mortality rates with our novel suture is is not significantly higher when compared to literature.Cardiopulmonary bypass time and cross clamp time needed to suture with our novel side exiting pledgetted sutures is likely to be less as they are more convenient for surgeons to use and they do not need to be checked as long by the operating surgeon.