Thrombocytopenia after transcatheter aortic valve implantation. A comparison between balloon-expandable and self-expanding valves

Coagulation, fibrinolysis and platelet drop in patients undergoing transfemoral transcatheter aortic valve implantation

BACKGROUND

Transcatheter aortic valve implantation (TAVI) leads to transient platelet activation and hypercoagulation status, resulting in thrombocytopenia.

AIMS

This study investigated the associations of coagulation/fibrinolysis status after transfemoral TAVI with valve type, post-TAVI thrombocytopenia, and complication of TAVI.

METHODS

Thrombin-antithrombin complex (TAT) and fibrin/fibrinogen degradation product (FDP) levels were measured before and 1 h, 1 day, and 2 days after TAVI. A percentage drop in platelet count (DPC) was determined from the pre- and lowest post-procedural values.

RESULTS

SAPIEN 3 (S3) was implanted in 158 patients and Evolut PRO/PRO+ (Evolut) in 117. Both TAT and FDP increased after TAVI. Pre-TAVI balloon dilatation was generally performed on patients undergoing implantation with Evolut. Peak TAT was then stratified into 4 quartiles (Q1 to Q4). Of all 275 study patients, 69 patients reached ultra-hypercoagulation status (Q4). S3, TAVI without pre-balloon dilatation, DPC and bleeding complications were significantly associated with the ultra-hypercoagulation status after TAVI. TAT was significantly greater 1 h after S3 implantation than Evolut (median [IQR], 43.1 [34.1-59.6] vs. 31.0 [25.0-40.4] ng/mL; p < 0.001). In contrast, FDP levels did not differ between the two at any measurement point. The difference in DPC among the peak TAT quartiles was statistically significant (p < 0.001). The occurrence of bleeding complications was significantly higher in the group with ultra-hypercoagulation status (5.8% vs. 1.0%, p = 0.036).

CONCLUSIONS

The increase in coagulation status and post-TAVI thrombocytopenia were significantly greater after S3 implantation. Ultra-hypercoagulation after TAVI was related to bleeding complications.

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.

Restoration of von Willebrand factor after transcatheter aortic valve replacement-A possible cause for posttranscatheter aortic valve replacement thrombocytopenia?

OBJECTIVES

The aim of the current study was to analyze the clinical and procedural predictors of thrombocytopenia and the relationship between the decrease in platelet count (DPC) and change in vWF function (ΔvWF) after transcatheter aortic valve replacement (TAVR).

BACKGROUND

TAVR often causes temporary thrombocytopenia. At the same time, TAVR leads to a restoration of von Willebrand factor (vWF) function.

METHODS

One hundred and forty-one patients with severe aortic stenosis undergoing TAVR were included in the study. Platelet count and vWF function (vWF:Ac/Ag ratio) were assessed at baseline and 6 h after TAVR. Thrombocytopenia was defined as platelet count <150/nL.

RESULTS

Median platelet count at baseline was 214/nL (interquartile range [IQR]: 176-261) and decreased significantly to 184/nL (IQR: 145-222) 6 h after TAVR. The number of patients with thrombocytopenia increased from 12.8% at baseline to 29.1% after 6 h. DPC 6 h after TAVR showed a significant correlation with ΔvWF (r = - 0.254, p = 0.002). Patients with DPC > 20% had significantly higher ΔvWF (10.9% vs. 6.5%, p = 0.021). Obese patients showed a significantly lower DPC (11.8% vs. 19.9%, p = 0.001). In multivariate analysis, ΔvWF 6 h after TAVR was the only significant predictor for DPC > 20% (p = 0.017).

CONCLUSIONS

The restoration of vWF after TAVR is a significant predictor for DPC after TAVR. An increased platelet consumption due to vWF restoration could play a key role in the development of thrombocytopenia after TAVR.

Predictive model for severe thrombocytopenia after transfemoral transcatheter aortic valve replacement

The aim of this study was to develop a predictive model for severe thrombocytopenia after transfemoral transcatheter aortic valve replacement (TAVR). A total of 155 patients treated with TAVR at our center were retrospectively enrolled in this study. The incidence of severe thrombocytopenia after TAVR was 25.16%, and most patients suffered from severe thrombocytopenia on 4 days after procedure. Multivariate regression analysis showed that weight <60 kg, New York Heart Association Functional Classification (NYHAFC IV), major vascular complications, and lower first post-procedural platelet count were independent risk factors for severe thrombocytopenia after TAVR. The c-statistic for the area under the curve was 0.758, the sensitivity was 0.744, the specificity was 0.784, and the negative predictive value of the model was 91.38%. The overall predictive value was 76.77%. The predictive model developed from this cohort data could effectively identify patients at high risk of severe thrombocytopenia after TAVR, and might be applicable to patients with aortic regurgitation (AR) and severe thrombocytopenia with different definitions.

Contemporary transcatheter aortic valve implantation related thrombocytopenia

BACKGROUND

Transcatheter aortic valve implantation related thrombocytopenia (TAVI-rTP) is an inevitable phenomenon. However, no study has been performed on TAVI-rTP in the current setting of extended clinical indications combined with technology improvements.

METHODS

Patients with severe symptomatic aortic stenosis who underwent transfemoral TAVI, from January 2016 to December 2019 were enrolled.

RESULTS

Two-hundred and one consecutive patients (mean age 81.1 ± 7.1 years, 96 men) enrolled. Platelet count was recorded before and after aortic valve implantation. Dropped platelet count (DPC) occurred in all but 11 patients who were included. Two groups were created: DPC <30 and DPC ≥30%. DPC was compared with in-hospital major adverse cardiovascular events. The mean DPC was 26 ± 14%. We found that 67 patients (33.3%) had DPC of more or equal to 30%. In the univariable analysis, the time of the procedure (94.4 ± 32.7 vs 79.4 ± 21.9, p = .002), the amount of the contrast used (125.4 ± 55.4 vs 108.4 ± 44.1, p = .02) and the residual AV gradient (13.3 ± 7.2 vs 14.7, p = .05) were related to a DCP ≥30%. A DPC ≥30% was associated with increased risk of life-threatening/major bleeding (11.9% vs 1.5%, p = .001), major vascular complications (16.4% vs 5.2% p = .009) and death (3.0% vs 0%, p = .044) at 30 days. After multivariable analysis, the factors associated with a higher DPC were time and contrast.

CONCLUSION

Contemporary TAVI-rTP in this cohort of patients continues to be a common phenomenon but severe thrombocytopenia is less frequent. Patients developing a DPC ≥30% are associated with poor outcomes at 30 days.

Predictors of short-term thrombocytopenia after transcatheter aortic valve implantation: a retrospective study at a single Japanese center

OBJECTIVE

Thrombocytopenia is common after transcatheter aortic valve implantation (TAVI) and is associated with mortality and major complications, although the underlying mechanisms are unclear. This retrospective single-center study aimed to identify factors associated with the decrease in platelet count (DPC) after TAVI in Japanese patients. Patients with severe aortic valve stenosis who underwent transfemoral TAVI between March 2014 and August 2019 were grouped according to DPC values of < 50% or ≥ 50% (DPC = 100% × [baseline platelet count-nadir platelet count]/[baseline platelet count]). Multivariable logistic regression analysis was performed to identify factors associated with a DPC of ≥ 50%.

RESULTS

Among the 131 patients who underwent transfemoral TAVI, 74 patients (56%) had a DPC of ≥ 50%, and 57 patients (44%) had a DPC of < 50%. Significant risk factors for a DPC of ≥ 50% were older age, lower body mass index (BMI), and use of balloon-expandable valves (BEV). The multivariable analysis revealed that a DPC of ≥ 50% was independently predicted by low BMI (adjusted odds ratio: 0.884, 95% confidence interval: 0.785-0.997; P = 0.039) and BEV use (adjusted odds ratio: 3.014, 95% confidence interval: 1.003-9.056; P = 0.045). Platelet count monitoring after TAVI, especially when using BEV devices, is essential for Japanese patients with low BMI.

Impact of postprocedural thrombocytopenia on mortality after transcatheter aortic valve implantation

AIMS

We performed a meta-analysis of currently available studies investigating the impact of postprocedural thrombocytopenia on mortality after transcatheter aortic valve implantation (TAVI).

METHODS

All studies researching the impact of postprocedural thrombocytopenia on mortality after TAVI were identified after searching PubMed and Web of Science through July 2019. The outcome of interest was early (in-hospital or 30-day) and overall (1- to 2-year) all-cause mortality after TAVI. From each study, the number of deaths in both patients with major (moderate/severe or higher postprocedural drop platelet counts defined in each study) and nonmajor (no/minor or lower drop platelet counts defined in each study) postprocedural thrombocytopenia was extracted. Then, odds ratios (ORs) of mortality for major vs. no/minor thrombocytopenia and their confidence intervals were generated. Alternatively, ORs and hazard ratios of mortality for major vs. no/minor thrombocytopenia (if available, adjusted) were directly extracted. Study-specific estimates were pooled in both the fixed-effect and random-effects models.

RESULTS

The principal pooled analysis demonstrated that postprocedural thrombocytopenia was associated with statistically significant increases in early (OR, 3.79; P for effect <0.00001; P for heterogeneity = 0.89) and overall mortality (OR/hazard ratio, 1.22; P for effect = 0.009; P for heterogeneity = 0.17) in the fixed-effect model. All sensitivity analyses did not substantively alter the results of the principal analysis. No funnel plot asymmetry of the principal analysis was detected (P for early mortality = 0.88; P for overall mortality = 0.14), which suggested probably no publication bias.

CONCLUSION

Postprocedural thrombocytopenia is associated with increased early and overall mortality after TAVI.

Predictor and Mid-Term Outcome of Clinically Significant Thrombocytopenia After Transcatheter Aortic Valve Selection

BACKGROUND

The frequency and predictors of thrombocytopenia after transcatheter aortic valve implantation (TAVI) are unclear.Methods and Results:This study enrolled 342 patients undergoing TAVI (245 with a percutaneous transfemoral approach, 65 with transfemoral surgical cutdown, and 32 with a non-transfemoral approach). Balloon-expandable and self-expanding valves were implanted in 235 and 107 patients, respectively. Platelet counts started to drop immediately, reaching a nadir 2-4 days after TAVI. Clinically significant thrombocytopenia (CSTP) was defined as a platelet count ≤50×10⁹/L at the time of the nadir or both a platelet count between 80 and 51×10⁹/L and a decrease in platelet count ≥50%. CSTP occurred in 16.7% patients. Approach site and TAVI valve selection significantly predicted CSTP. In multivariate analysis, independent predictors of CSTP were liver cirrhosis (odds ratio [OR] 7.22; 95% confidence interval [CI] 1.05-49.82), baseline platelet count ≤120×10⁹/L (OR 2.98; 95% CI 1.20-7.38), multiple blood transfusions (OR 4.03; 95% CI 1.72-9.41), and the use of balloon-expandable valves (OR 2.38; 95% CI 1.04-5.46). Kaplan-Meier survival analysis with a generalized Wilcoxon test revealed that mid-term (2 years) mortality was greater for patients with than without CSTP (31.4% vs. 15.5%; P=0.008).

CONCLUSIONS

TAVI-related CSTP was not rare and was associated with poor mid-term outcomes. CSTP was not only caused by patients' comorbidities and TAVI complications, but also related to TAVI procedural factors.

Anticoagulation after Transcatheter Aortic Valve Implantation: Current Status

Transcatheter aortic valve implantation (TAVI) is the standard of care for symptomatic severe aortic stenosis. Antithrombotic therapy is required after TAVI to prevent thrombotic complications but it increases the risk of bleeding events. Current clinical guidelines are mostly driven by expert opinion and therefore yield low-grade recommendations. The optimal antithrombotic regimen following TAVI has yet to be determined and several randomised controlled trials assessing this issue are ongoing. The purpose of this article is to critically explore the impact of antithrombotic drugs, especially anticoagulants, on long-term clinical outcomes following successful TAVI.

In-Hospital Outcomes After Transcatheter Aortic Valve Implantation in Patients With Versus Without Chronic Thrombocytopenia

Patients with chronic thrombocytopenia (cTCP) were excluded from the pivotal transcatheter aortic valve implantation (TAVI) trials. The National Inpatient Sample was queried and propensity score matching was performed to evaluate the prevalence and impact of cTCP on in-hospital clinical outcomes after TAVI. The main outcome was in-hospital mortality in patients with versus without cTCP. Among 38,855 TAVI hospitalizations, 7,105 had a diagnosis of cTCP (18.3%). In-hospital mortality was similar in both groups (OR_adjusted 0.79; 95% confidence interval [CI] 0.57 to 1.09); however, cTCP was associated with higher risk of acute kidney injury (OR_adjusted 1.29; 95% CI 1.08 to 1.54), vascular complications (OR_adjusted 1.99; 95% CI 1.22 to 3.25), perioperative blood product transfusion (OR_adjusted 1.69; 95% CI 1.42 to 2.01), cardiac tamponade (OR_adjusted 4.04; 95% CI 1.51 to 10.82), cardiogenic shock (OR_adjusted 1.52; 95% CI 1.07 to 2.15), and use of extracorporeal membrane oxygenation (OR_adjusted 2.32; 95% CI 1.1 to 4.9). In conclusion, cTCP is common in patients who underwent TAVI and is associated with worse postprocedure clinical outcomes, however, with similar in-hospital mortality.

Antithrombotic pharmacotherapy after transcatheter aortic valve implantation: an update

Introduction: Transcatheter aortic valve implantation (TAVI) is the treatment of choice for a large proportion of patients with severe aortic stenosis. Despite numerous technological and clinical advances, TAVI remains associated with thrombotic complications requiring antithrombotic pharmacotherapy, which exposes to the risk of bleeding, especially in elderly individuals. The optimal antithrombotic regimen following TAVI is uncertain and several investigations are ongoing. Areas covered: Clinical guidelines are mostly driven by observational trials and experts' opinions, thus resulting into low-grade level of evidence. The aim of the current review is to critically explore the epidemiology, pathophysiology and prognostic value of thrombotic and bleeding events after TAVI, and to review the current literature on antithrombotic strategies following the procedure. Expert opinion: Thrombotic and bleeding events remain major complications occurring in the frail population that is currently offered TAVI. Waiting for upcoming evidence from ongoing randomized clinical trials, tailoring antithrombotic therapies based on patients' characteristics, values and circumstances is a preferable approach.