Thrombocytopenia After Aortic Valve Replacement With Freedom Solo Bioprosthesis: A Propensity Study

Thrombocytopenia Following Perceval Sutureless Aortic Valve Replacement in Asian Patients

BACKGROUND

This study analyzed the safety and performance of the Perceval valve for aortic valve replacement (AVR) in patients at 1 year after undergoing aortic stenosis (AS) treatment, and its effect on significant declines in the platelet count during the immediate postoperative period.

METHODS AND RESULTS

Data were collected retrospectively for the initial 121 patients (median age 77 years; 47.1% females) who underwent Perceval sutureless AVR between May 2019 and July 2022. Implantation was successful in all (100%), with median cross-clamp and CPB times of 59 and 100 min, respectively. Postoperative thrombocytopenia (platelet count <50×103/μL) was noted in 80 (66.1%) patients. Multivariate analysis showed advanced age (>80 years), preoperative low platelet count (<200×103/μL), and a sternotomy approach as significant risk factors for postoperative thrombocytopenia. One (0.8%) patient died within 30 days after the procedure. The 2-year site-reported event rate was 14% (n=17) for all-cause mortality, 0.8% (n=1) for cardiac mortality, 4.1% (n=5) for stroke, and 1.7% (n=2) for endocarditis and valve-related reoperation; there were no instances of paravalvular leakage or structural valve deterioration.

CONCLUSIONS

Thrombocytopenia was common after Perceval sutureless AVR, although its impact was not significant. Although Perceval sutureless AVR was found to be a safe and effective option, preoperative assessment of potential bleeding should be performed and the Perceval valve should not be used for patients with a high bleeding risk.

Spleen Size and Thrombocytopenia After Transcatheter Aortic Valve Implantation

The pathophysiology of thrombocytopenia after transcatheter aortic valve implantation (TAVI) thrombocytopenia is still poorly understood. We assessed the association of spleen size with acquired thrombocytopenia in patients undergoing TAVI. We included 732 patients who underwent TAVI with new generation transcatheter heart valves (THVs) at our center from February 2016 to July 2019. We measured splenic volume index in consecutive patients derived from multidetector row computed tomographic datasets. Patients were stratified according to post-TAVI thrombocytopenia, which was defined as a decline in platelet count (DPC) ≥50% at nadir, and evaluated regarding baseline characteristics and outcome parameters. After the procedure, platelet counts declined from 212.9 ± 67.4 × 10⁹/L at baseline to 138.8 ± 49.8 × 10⁹/L at nadir after a median of 2 days (interquartile range [IQR] 2 to 3). Of all patients, 10.1% showed a DPC ≥50%. Compared with patients with DPC <50%, patients with DPC ≥50% had significantly lower splenic volume index (95.5 ml/m² [IQR 78.0 to 123.7] vs 85.8 ml/m² [IQR 71.4 to 102.6], p = 0.008). A multivariable analysis revealed that the splenic volume index was negatively associated with a DPC ≥50% (OR 0.89, 95% CI 0.82 to 0.97, p = 0.005), independent of the type of THV (balloon-expandable THV: OR 2.06, 95% CI 1.13 to 3.76, p = 0.02), major bleeding (OR 13.40, 95% CI 3.58 to 50.40, p <0.001), blood transfusion (OR 3.63, 95% CI 1.54 to 8.56, p = 0.003), or postprocedural paravalvular leakage ≥moderate (OR 5.48, 95% CI 1.23 to 24.40, p = 0.03). Furthermore, DPC ≥50% was independently associated with 1-year mortality (HR 3.36, 95% CI 1.66 to 6.81, p <0.001). In conclusion, acquired thrombocytopenia remains prevalent in modern TAVI patients. Spleen size appears to be associated with the occurrence of thrombocytopenia after TAVI, which is independently correlated with 1-year mortality.

Quantitative and Qualitative Platelet Derangements in Cardiac Surgery and Extracorporeal Life Support

Thrombocytopenia and impaired platelet function are known as intrinsic drawbacks of cardiac surgery and extracorporeal life supports (ECLS). A number of different factors influence platelet count and function including the inflammatory response to a cardiopulmonary bypass (CPB) or to ECLS, hemodilution, hypothermia, mechanical damage and preoperative treatment with platelet-inhibiting agents. Moreover, although underestimated, heparin-induced thrombocytopenia is still a hiccup in the perioperative management of cardiac surgical and, above all, ECLS patients. Moreover, recent investigations have highlighted how platelet disorders also affect patients undergoing biological prosthesis implantation. Though many hypotheses have been suggested, the mechanism underlying thrombocytopenia and platelet disorders is still to be cleared. This narrative review aims to offer clinicians a summary of their major causes in the cardiac surgery setting.

Heart valve mechanical prosthesis: The perfect match until it is not - A case report

Primary immune thrombocytopenia (ITP), formerly known as idiopathic thrombocytopenia, is defined by a reduced platelet count <50x10⁹ and is clinically manifested through signs and symptoms such as bleeding, ecchymosis and petechiae. Its coexistence with the implantation of the mechanical valves and the necessity of anticoagulation creates an additional risk of bleeding. Although mechanical valves are indispensable in prolonging and improving the quality of life in patients with valvular heart disease, in the context of an additional bleeding risk factor, their presence could represent a threat to life exposing the patient to major complications and leading to death. The purpose of this case report is to discuss the disadvantages and possible fatal complications of the association between mechanical valves and severe thrombocytopenia. A possible solution to these downsides could be found in the future search in regenerative medicine and tissue engineering of heart valves resulting in products that do not require anticoagulation and do not pose a threat to patients with thrombocytopenia.

Two approaches-one phenomenon-thrombocytopenia after surgical and transcatheter aortic valve replacement

BACKGROPUND AND AIM

Postoperative thrombocytopenia after surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) and aggravating causes were the aim of this retrospective study.

METHODS

Data of all patients treated with SAVR (n = 1068) and TAVR (n = 816) due to severe aortic valve stenosis was collected at our center from 2010 to 2017. Preprocedural and postprocedural values were collected from electronic patient records.

RESULTS

There was a significant drop in platelets in both groups, the TAVR group showed overall superior platelet preservation compared to the AVR group (P < .001). In the SAVR subgroup analysis, a significant difference in platelet preservation was observed between the valve types (P < .001), particularly with the Freedom SOLO valve. In the TAVR subgroup analysis, the valve type did not influence platelet count (PLT) reduction (P = .13). In the SAVR subgroup analyses, PLT was found to be worsened with cardiopulmonary bypass (CPB) duration.

CONCLUSION

Thrombocytopenia frequently occurs after implantation of a biological heart valve prosthesis, with a higher frequency observed in patients after cardiac surgery rather than TAVR. Although some surgical bioprosthetic models are more susceptible to this phenomenon, CPB duration seems to be a major determinant for the development of postoperative thrombocytopenia.

Peri-procedural thrombocytopenia after aortic bioprosthesis implant: A systematic review and meta-analysis comparison among conventional, stentless, rapid-deployment, and transcatheter valves

BACKGROUND

Thrombocytopenia has been shown to occur soon after surgical biological aortic valve replacement (AVR), and recently reported also after transcatheter valve implantation (TAVI). The mechanism underlying this phenomenon is still unknown, and its clinical impact on the peri-operative outcome has been poorly investigated.

METHODS

A systematic review and a meta-analysis of all available studies reporting data about peri-procedural thrombocytopenia on isolated bio-AVR, comparing rapid-deployment (RDV), stentless (stentless-AVR), and TAVI vs. stented (stented-AVR) valves, have been performed.

RESULTS

Fifteen trials (2.163 patients) were included in the meta-analysis. Perioperative platelet reduction ranged from 35% to 55% in stented-AVR, from 60% to 77% in stentless-AVR, from 53% to 60% in RDV, and from to 21% to 72% in TAVI (apparently, balloon-expandable valves more frequently associated to thrombocytopenia). Stented-AVR required more red blood cells transfusion than stentless-AVR (P < 0.0001), whereas no difference has been found between RDV and stented-AVR. Platelet transfusion rate was very low in all surgical groups. No difference has been found in RDV and stentless-AVR vs. stented-AVR, in terms of reoperation for bleeding, and length-of-intensive care unit or hospital stay.

CONCLUSIONS

Thrombocytopenia-related major adverse events were mainly reported in TAVI patients, whereas clinically meaningless in surgical patients. Transient peri-procedural thrombocytopenia is common after bio-AVR, regardless of prosthesis's type or implant modality. It should receive appropriate monitoring and focused investigations.

Thrombocytopenia After Transcatheter Valve-in-Valve Implantation: Prognostic Marker or Mere Finding?

Objective

To analyze the behavior of platelets after transcatheter valve-in-valve implantation for the treatment of degenerated bioprosthesis and how they correlate with adverse events upon follow-up.

Methods

Retrospective analysis of 28 patients who received a valve-in-valve implant, 5 in aortic, 18 in mitral and 5 in tricuspid positions. Data were compared with 74 patients submitted to conventional redo valvular replacements during the same period, and both groups' platelet curves were analyzed. Statistical analysis was conducted using the IBM SPSS Statistics(r) 20 for Windows.

Results

All patients in the valve-in-valve group developed thrombocytopenia, 25% presenting mild (<150.000/µL), 54% moderate (<100.000/µL) and 21% severe (<50.000/µL) thrombocytopenia. The platelet nadir was on the 4^th postoperative day for aortic ViV, 2^nd for mitral and 3^rd for tricuspid patients, with the majority of patients recovering regular platelet count. However, the aortic subgroup comparison between valve-in-valve and conventional surgery showed a statistically significant difference from the 7^th day onwards, where valve-in-valve patients had more severe and longer lasting thrombocytopenia. This, however, did not translate into a higher postoperative risk. In our study population, postoperative thrombocytopenia did not correlate with greater occurrence of adverse outcomes and only normal preoperative platelet count could significantly predict a postoperative drop >50%.

Conclusion

Although thrombocytopenia is an extremely common finding after valve-in-valve procedures, the degree of platelet count drop did not correlate with greater incidence of postoperative adverse outcomes in our study population.

Thrombocytopenia After Aortic Valve Replacement: Comparison Between Sutureless Perceval S Valve and Perimount Magna Ease Bioprosthesis

Introduction

The incidence of postoperative thrombocytopenia after aortic valve replacement (AVR) with the Perceval S Sutureless bioprosthesis remains unclear. The aim of this study was to report thrombocytopenia associated with the use of sutureless AVR.

Methods

The data was collected retrospectively for patients who had isolated AVR with sutureless Perceval S valve (Group A: 72 patients) and was compared with patients who underwent isolated sutured AVR with Perimount Magna Ease Bioprosthesis (Group B: 101 patients) in our institution between June 2014 and January 2017.

Results

Cardiopulmonary bypass and cross-clamp time were significantly shorter in group A. Maximum drop in platelet count was 58% mean (day 2.3) in group A versus 44% mean (day 1.7) in group B (P=0.0001). Absolute platelet count on postoperative day 1-6 in group A was significantly less than in group B (P≤0.05). Platelet count recovered to preoperative value in 44% patients in group B versus only in 26% patients in group A at discharge (P=0.018). Moderate thrombocytopenia occurs more often in group A (41% vs. 26%) (P=0.008) while severe thrombocytopenia (<50 x 10⁹) was observed in 6% in group A but never in group B. Platelets (P=0.007) and packed red blood cells (P=0.009) transfusion was significantly higher in the group A.

Conclusion

The implantation of sutureless Perceval aortic valves was associated with a significant drop in platelet count postoperatively with slow recovery and higher platelets and packed red blood cells transfusion requirements. A prospective randomised trial is needed to confirm our findings.

Predictors of Thrombocytopenia after Self-Expandable Transcatheter Aortic Valve Replacement: A Single-Center Experience from China

OBJECTIVES

The importance of thrombocytopenia (TP) has been discussed previously. However, data are still limited, especially on predictors of TP. We sought to investigate predictors of TP after transcatheter aortic valve replacement (TAVR), in particular, clinically significant TP.

METHODS

We reviewed a total of 123 consecutive patients undergoing TAVR in our medical center. They were stratified into 3 groups according to the nadir platelet count post-TAVR: no/mild TP, moderate TP, and severe TP. Clinically significant TP, also known as major TP, was defined as moderate-to-severe TP (a nadir platelet count <100 × 109/L and a >50% decrease in platelet count).

RESULTS

Baseline platelet, baseline hemoglobin, general anesthesia (GA), valve malpositioning and post-TAVR left ventricular ejection fraction were found to be predictors of post-TAVR nadir platelet count. Major TP was associated with a higher risk of major bleeding (OR 3.524, 95% CI 1.546-8.031) and 1-month mortality (OR 11.226, 95% CI 1.208-104.328). Age (OR 1.110, 95% CI 1.014-1.215) and GA (OR 6.494, 95% CI 2.058-20.408) were predictors of major TP.

CONCLUSION

Post-TAVR nadir platelet count can be predicted based on baseline and procedural data. Old age and GA contribute to clinically significant TP.

Thrombocytopenia associated with TAVI-The summary of possible causes

Thrombocytopenia (TP) following transcatheter aortic valve implantation (TAVI) procedure is a common phenomenon but the underlying mechanisms are neither well known nor described. Postinterventional severe TP is related to worse early and late outcome. Moreover, the statement of enhanced platelet and coagulation activation might justify even stronger antiplatelet and anticoagulation therapy following TAVI procedure. Thus, the examination of the pathomechanisms responsible for TP post TAVI seems to be crucial. Several hypotheses have been raised. TP can be caused by insufficient production or impaired platelet renewal. On the other hand, increased platelet activation, consumption and destruction might also be responsible for TP. These findings, mostly related to the procedure alone, need further investigation. Here, we summarize the potential multifactorial causes of post TAVI thrombocytopenia.

A European Multicenter Study of 616 Patients Receiving the Freedom Solo Stentless Bioprosthesis

BACKGROUND

The purpose of this study was to evaluate the safety and performance of the Freedom Solo valve in aortic valve replacement by clinical and hemodynamic outcomes.

METHODS

Six hundred sixteen patients underwent aortic valve replacement in 18 European centers; mean age was 74.5 ± 5.9 years, 54.1% of the patients were male, and concomitant procedures were performed in 43.2% of the patients. The majority (69%) of the implanted sizes were 23 mm and 25 mm.

RESULTS

At 1 year, overall survival was 94.0%, whereas freedom from valve-related death was 98.6%. There were 9 (1.5%) early (≤ 30 days) and 27 (4.4%) late (>30 days) deaths. Early and late valve-related mortality was 0.3% (n = 2) and 1.1% (n = 7), respectively. Freedom from explant was 97.6%; 10 valves were explanted for endocarditis and 4 for paravalvular leak. There were 10 (1.6%) early and 5 (0.8%) late strokes. Atrioventricular block requiring pacemaker implant occurred in 8 (1.3%) and 1 (0.2%) patients in the early and late postoperative period, respectively. Thrombocytopenia was seen in 27 cases (4.4%) in the early postoperative period. Preoperatively, 93.8% of patients were in New York Heart Association functional classes II through IV, whereas at 1 year 96.9% of patients were in New York Heart Association functional classes I and II. At 1-year follow-up, mean and peak pressure gradients were 7.2 and 14.6 mm Hg, respectively. Indexed left ventricular mass decreased by 12% from 138 g/m(2) at discharge to 122 g/m(2) at 1 year.

CONCLUSIONS

At 1-year follow-up after Freedom Solo implantation, we found acceptable clinical results with low mortality and morbidity and good hemodynamic performance, confirming safety and effectiveness in this multicenter experience.

North American trial results at 1 year with the Sorin Freedom SOLO pericardial aortic valve

OBJECTIVES

A North American prospective, 15-centre Food and Drug Administration (FDA) valve trial was designed to assess the safety and effectiveness of the Freedom SOLO stentless pericardial aortic valve in the treatment of surgical aortic valve disease.

METHODS

Beginning in 2010, 251 patients (mean: 74.7 ± 7.5 years), were recruited in the Freedom SOLO aortic valve trial. One hundred eighty-nine patients have been followed for at least 1 year and are the basis for this review. Preoperatively, 54% of patients had NYHA functional class III or IV symptoms, and the majority of patients had a normal ejection fraction (EF) (median EF = 61%). Concomitant procedures were performed in 61.9% of patients, with coronary artery bypass grafting (CABG) (48.7%) being the most common followed by a MAZE procedure (13.7%). Reoperations were performed in 8.5% of patients in the study.

RESULTS

The entire cohort of 251 patients enrolled had 7 deaths prior to 30 days, 2 of which were valve-related (aspiration pneumonia and sudden death) and 5 were not valve-related. There were 11 deaths after 30 days, 1 valve-related (unknown cardiac death) and 10 not valve-related. Five valves were explanted, 3 early (endocarditis, acute insufficiency and possible root dissection) and 2 late (endocarditis). Thirty-day adverse events include arrhythmias requiring permanent pacemaker (4.2%), thromboembolic events (3.7%) and thrombocytopenia (7.4%). One-year follow-up of all 189 patients demonstrated mean gradients for valve sizes 19, 21, 23, 25 and 27 mm of 11.7, 7.8, 6.3, 4.6 and 5.0 mmHg, respectively. Effective orifice areas for the same valve sizes were 1.2, 1.3, 1.6, 1.8 and 1.9 cm(2), respectively. Ninety-six percent of patients (181/189) were in NYHA class I or II at the 1-year follow-up.

CONCLUSIONS

The Freedom SOLO stentless pericardial aortic valve demonstrated excellent haemodynamics and a good safety profile out to the 1 year of follow-up.

Predictors and clinical impact of pre-existing and acquired thrombocytopenia following transcatheter aortic valve replacement

BACKGROUND

Data are limited regarding transcatheter aortic valve replacement (TAVR)-related thrombocytopenia (TP). We sought to thoroughly characterize the presence, clinical impact, and severity of TP associated with TAVR.

METHODS AND RESULTS

Data were collected from 90 patients who underwent TAVR using the Edwards SAPIEN valve (59 TF, 29 TA, 2 Tao). Platelet counts were evaluated peri-procedurally and for 8 days following TAVR. Platelet levels were compared and patients were divided into a no TP (No-TP) group 1, acquired (new) TP (NTP) group 2, pre-existing (pre-TAVR) TP (PTP) group 3, and further stratified based on the severity of TP: mild (M) TP (100-149 × 10(3) cell/µL) and moderate-severe (MS) TP (<100 × 10(3) cell/µL). Pre-TAVR point prevalence and post-TAVR incidence of TP were 40% and 79%, respectively (P < 0.001); nadir platelet count in all groups occurred day 4 post-TAVR. Baseline predictors for developing MS TP in groups 2-3 included baseline TP, leaner body mass, smaller pre-procedural aortic valve area, higher peak aortic jet velocity, and worsening baseline renal function. Development of "major" TP (nadir platelet count <100 × 103 cell/µL, ≥50% decrease) predicted a higher risk of major vascular complications (OR 2.78 [95% CI, 1.58-3.82]) and major bleeding (OR 3.18 [95% CI, 1.33-5.42]) in group 3.

CONCLUSION

TAVR-related TP is predictable and classification by PTP and TP severity prior to TAVR allows for better risk stratification in predicting in-hospital clinical outcomes. Major TP in the presence of worsening TP is predictable and is associated with worse clinical outcomes. © 2014 Wiley Periodicals, Inc.

Evaluation of platelet count after isolated biological aortic valve replacement with Freedom Solo bioprosthesis

OBJECTIVE

The risk of thrombocytopenia in patients undergoing aortic valve replacement (AVR) with the Freedom Solo (FS) bioprosthesis is controversial. The aim of our study was to evaluate the postoperative evolution of platelet count and function after AVR in patients undergoing isolated biological AVR with FS.

METHODS

Between May 2005 and June 2010, 322 patients underwent isolated biological AVR. Of these, 116 patients received FS and were compared with 206 patients who received biological valves. Platelet count, mean platelet volume (MPV), and platelet distribution width (PDW) were evaluated at baseline (T0), first (T1), second (T2), and fifth (T3) postoperative days, respectively.

RESULTS

Overall in-hospital mortality was 1.5% with no difference between the two groups. Thirty-seven (11.5%) patients developed thrombocytopenia. FS implantation was associated with a higher incidence of thrombocytopenia compared with the control group (24.1% vs 4.4%, p<0.0001). Patients in the FS group showed a lower platelet count than the control group at T1 (99.4±38×10(3) μl(-1) vs 122.5±41.6×10(3) μl(-1), p<0.001), T2 (79.7±36.3×10(3) μl(-1) vs 122.5±43.3×10(3) μl(-1), p<0.001) and T3 (86.6±57.4×10(3) μl(-1) vs 158.4±55.8×10(3) μl(-1), p<0.001). Moreover, the FS group also had a higher MPV (11.6±0.9 fl vs 11±1 fl, p<0.001) and higher PDW (15.1±2.3 fl vs 13.9±2.1 fl, p<0.001) at T3. In a multivariable analysis, FS (p<0.0001), body surface area (p<0.0001), cardiopulmonary bypass time (p=0.003), and lower preoperative platelet counts (p=0.006) were independent predictors of thrombocytopenia.

CONCLUSIONS

The FS valve might increase the risk of thrombocytopenia and platelet activation, in the absence of adverse clinical events. Prospective randomized studies on platelet function need to confirm our data.

Platelet reduction after stentless pericardial aortic valve replacement

The aim of the study was to investigate the multi-factorial phenomenon of possible postoperative thrombocytopenia after aortic valve replacement (AVR) with the freedom SOLO (FS) bioprosthesis. A total of 254 patients underwent AVR with FS bioprosthesis in two cardiac surgery institutes. Platelet counts were measured preoperatively, immediately postoperatively and daily until the 11th day postoperatively. A multivariate generalized estimating equation model was applied to identify prognostic factors for whether or not patients postoperative platelet counts indicated no thrombocytopenia (platelet count >150 10(3)/mm(3)) versus at least mild thrombocytopenia (≤150 10(3)/mm(3)). Preoperatively, 11.2% of patients showed thrombocytopenia. The preoperative platelet count averaged 233.0 ± 83.2 10(3)/mm(3). The postoperative mean of platelet counts decreased daily reaching a minimum mean of 88.4 ± 58.8 10(3)/mm(3) 3 days after surgery and then started to increase, with the Day 11 postoperative mean of 173.3 ± 51.8 10(3)/mm(3). Compared with patients with no preoperative thrombocytopenia, patients with preoperative thrombocytopenia had an 8.69 increased odds of being in the group with postoperative platelet count <150 10(3)/mm(3). No major haemorrhagic or thromboembolic event was reported during hospitalization. This study shows that thrombocytopenia after the FS bioprosthesis replacement is a transient postoperative phenomenon, largely resolved within a few days after surgery, with no clinical consequences and haemodynamic dysfunction.