Letter to the Editor: Thrombocytopenia After Sutureless Aortic Valve Implantation: Does It Really Matter?

Despite the limited clinical relevance of thrombocytopenia after bioprosthetic aortic valve replacement (AVR), the postoperative depletion of platelet count continues to attract the attention of many authors. The development of thrombocytopenia has been evaluated either in patients receiving a sutureless bioprosthesis (1,2) or in those undergoing transcatheter aortic valve implantation, where cardiopulmonary bypass bears little or no relation to this phenomenon (3). Recently, Sánchez et al. (1) have published their findings on this topic, but their limited experience with the devices used makes their study of doubtful interest. Over three years, 27 patients were implanted with a sutureless bioprosthetic valve and were compared with 50 patients receiving a stented aortic valve. No risk factors that may have predisposed to platelet dysfunction were described in either group.Mortality and number of units of transfused red blood cells also seems to be extremely high for a patient population undergoing elective isolated AVR: it is not clear whether bleeding complications occurred in any patients and re-thoracotomy could not be performed, or whether more liberal transfusion protocols were used. In addition, platelet transfusions in patients from the sutureless group could represent a bias that renders the comparison of postoperative mean platelet volume and platelet distribution width between groups unreliable. It would have been more appropriate to consider postoperative echocardiographic findings because, in case of suboptimal placement of the prosthesis, paravalvular leakage may cause severe hemolysis and thrombocytopenia. At present, clinical data can be derived from other case series (4). At our Center, over a six-year period, AVR was performed using a sutureless, stentless, or stented bioprosthesis in 432, 193, and 180 patients, respectively, with all devices being supplied by the same manufacturer. Perioperative trends in platelet count after sutureless AVR did not show progression towards thrombocytopenia as occurs after stentless AVR (5), but compared favourably with conventional stented AVR (Fig. 1), where platelet depletion has no clinical relevance. Figure 1: Perioperative trends in platelet count after aorticvalve replacement with the sutureless Perceval, stentlessSolo, and stented Crown bioprosthetic valves.References1. Sánchez E, Corrales JA, Fantidis P, Tarhini IS, Khan I, Pineda T, González JR. Thrombocytopenia after aortic valve replacement with Perceval S sutureless bioprosthesis. J Heart Valve Dis 2016;25:75-812. Jiritano F, Cristodoro L, Malta E, Mastroroberto P. Thrombocytopenia after sutureless aortic valve implantation: Comparison between Intuity and Perceval bioprostheses. J Thorac Cardiovasc Surg 2016;152:1631-16333. McCabe JM, Huang PH, Riedl LA, et al. Incidence and implications of idiopathic thrombocytopenia following transcatheter aortic valve replacement with the Edwards Sapien® valves: A single center experience. Catheter Cardiovasc Interv 2014;83:633-6414. Santarpino G, Fischlein T, Pfeiffer S. A word of caution is needed before uttering a word of caution: Thrombocytopenia and sutureless valves. Heart Surg Forum 2016;19:E1695. Pozzoli A, De Maat GE, Hillege HL, Boogaard JJ, Natour E, Mariani MA. Severe thrombocytopenia and its clinical impact after implant of the stentless Freedom Solo bioprosthesis. Ann Thorac Surg 2013;96:1581-1586.