Considerations in antithrombotic therapy among patients undergoing transcatheter aortic valve implantation

A Propensity-Matched National Analysis of Transcatheter Aortic Valve Implantation Outcome in Patients With Gastrointestinal Bleeding

Gastrointestinal (GI) bleeding is often observed in severe aortic stenosis, which can be attributed to the presence of arteriovenous malformations and von Willebrand's factor deficiency. GI is one of the most common complications in patients who underwent transcatheter aortic valve implantation (TAVI). The outcome of the TAVI procedure with GI bleeding is unknown. We performed an International Classification of Diseases, Tenth Revision-based national cohort analysis using the national readmission database from 2016 to 2020. We compared cardiovascular outcomes, mortality, and readmission rates of patients with TAVI who developed GI bleeding compared with those who had no GI bleeding. A total of 320,353 hospitalizations with TAVI were identified from the year 2016 to 2020. Patients with TAVI with GI bleeding were 6,193.37 and without GI bleeding were 314,160. The median age of the patients with TAVI with GI or without GI bleeding was 80. GI bleed patients had statistically significantly higher readmission rates at 30, 90, and 180 days and they had higher odds of in-hospital mortality (adjusted odds ratio [aOR] = 6.35; 95% confidence interval [CI]: 5.37 to 7.52; p <0.0001), acute kidney injury (aOR = 5.22; 95% CI:4.75 to 5.74; p <0.0001), stroke (aOR = 2.83; 95% CI 2.05 to 3.91 p:0.0001, postprocedural bleeding (aOR: 1.76; 95% CI: 1.35 to 2.30; p:0.0001), cardiac tamponade (aOR = 2.54; 95% CI 1.86 to 3.49; p <0.0001), use of mechanical circulatory support (aOR: 5.33; 95% CI:4.13 to 6.86; p <0.0001), and heart failure (aOR:1.73; 95%CI: 1.54 to 1.94; p <0.0001). The total cost of hospitalization and length of stay was higher in the GI bleed group. Patients with TAVI with GI bleeding have worse clinical outcomes and higher in-hospital mortality and readmission rates compared with patients with no GI bleeding.

Incidence, Current Guidelines and Management of Gastrointestinal Bleeding after Transcatheter Aortic Valve Replacement: A Systematic Review

BACKGROUND

There is a significant increase in morbidity and mortality in patients complicated by major bleeding following transcatheter aortic valve replacement (TAVR). It has become more challenging to manage such complications when the patient needs to be on anticoagulation or antiplatelet agent post-procedure to prevent thrombotic/embolic complications.

METHODS

We systematically reviewed all available randomized controlled trials and observational studies to identify incidence rates of gastrointestinal bleeding post-procedure. After performing a systematic search, a total of 8731 patients from 15 studies (5 RCTs and 10 non-RCTs) were included in this review.

RESULTS

The average rate of gastrointestinal bleeding during follow-up was 3.0% in randomized controlled trials and 1.9% among observational studies.

CONCLUSION

Gastrointestinal bleeding has been noted to be higher in the RCTs as compared to observational studies. This review expands knowledge of current guidelines and possible management of patients undergoing TAVR.

Efficacy and safety outcomes in novel oral anticoagulants versus vitamin-K antagonist on post-TAVI patients: a meta-analysis

Background

Transcatheter aortic valve implantation (TAVI) has been a favored option for the patient who suffered from symptomatic aortic stenosis. However, the efficacy and safety outcomes in novel oral anticoagulants (NOACs) versus Vitamin-K antagonist (VKA) for post-TAVI patients are still controversial. This meta-analysis aims at comparing the clinical outcome and safety of NOACs and VKA in the patients after receiving TAVI.

Method

We searched literature articles in all reachable databases, and observational study as well as randomized controlled trial would be included in order to perform a comprehensive analysis. All-cause mortality, major or life-threatening bleeding, disabling or nondisabling stroke were main pooled outcome measures. Subgroup analysis and meta-regression were adopted to explore heterogeneity. Assessment of bias was performed under the suggestion of Cochrane’s Collaboration Tool.

Results

We collected 3841 non-duplicate citations from PubMed, Embase, Cochrane and ClinicalTrials.gov, and eventually 7 studies were included for this meta-analysis. As a result, VKA showed priority against NOACs in the field of anti-thromboembolism (4435 participants, RR:1.44, 95% CI: 1.05 to 1.99, I² = 0%, P = 0.02).

Conclusion

With corroborative analysis of severe complications, VKA is shown to be more protective on post-TAVI patients in disabling or nondisabling stroke scenario but not in mortality or bleeding event.

Feasibility and safety of vitamin K antagonist monotherapy in atrial fibrillation patients undergoing transcatheter aortic valve implantation

AIMS

We aimed to assess the efficacy and safety of vitamin K antagonist (VKA) monotherapy in atrial fibrillation (AF) patients undergoing transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

In 735 TAVIs since 2008 we identified 167 patients suffering from concomitant AF who received either VKA monotherapy (n=77), VKA plus single antiplatelet therapy (SAPT, n=41) or a triple anticoagulation regimen (n=49). Thromboembolic as well as bleeding complications were analysed for six months after TAVI. Only one minor bleeding and no thromboembolic events occurred after VKA therapy had been initiated post TAVI. Compared to patients being treated with additional either single or dual antiplatelet therapy, the incidence of major/life-threatening bleeding complications was significantly lower in the VKA mono group (0/77 [VKA mono] vs. 3/41 [VKA+SAPT; p=0.04] vs. 4/49 [triple anticoagulation; p=0.02]). Analysis of a combined endpoint of post-procedural death, stroke, embolism and major bleeding revealed a significant superiority of VKA monotherapy compared to VKA plus SAPT or DAPT, respectively (5/77 vs. 9/41 [p=0.02] vs. 14/49 [p=0.002]).

CONCLUSIONS

VKA therapy without additional antiplatelet treatment is effective and safe in AF patients undergoing TAVI.

Upper gastrointestinal bleeding following transcatheter aortic valve replacement: A retrospective analysis

OBJECTIVES

The aim of this study was to identify the incidence of upper gastrointestinal bleeding (UGIB) in the postprocedural period following transcatheter aortic valve replacement (TAVR).

BACKGROUND

As TAVR moves into intermediate- and low-risk patients, it has become increasingly important to understand its extracardiac complications. The patient population undergoing TAVR have clinical and demographic characteristics that place them at significant risk of UGIB. Practical aspects of TAVR, including use of antithrombotic therapy, further increase risk of UGIB.

METHODS

A retrospective single-center evaluation of 841 patients who underwent TAVR between January 2005 and August 2014 was performed in conjunction with analysis of referral patterns to the gastroenterology service for UGIB at the same site.

RESULTS

The overall risk of UGIB following TAVR was found to be 2.0% (n = 17/841). Additionally, the risk of UGIB in patients receiving triple antithrombotic therapy was found to be 10-fold greater than patients not receiving triple antithrombotic therapy (11.8% vs 1.0%). Endoscopy findings demonstrated five high-risk esophageal lesions including erosive esophageal ulcers, visible vessels at the GE junction, erosions at distal esophagus, and an actively bleeding esophageal ring that had been intubated through by the transesophageal echocardiography (TEE) probe.

CONCLUSIONS

This large cohort study demonstrates that TAVR is associated with a moderate risk of severe UGIB. The results of this study suggest that patients on triple antithrombotic therapy are at highest risk for severe UGIB. © 2016 Wiley Periodicals, Inc.

Is Transcatheter Aortic Valve Implantation of Living Tissue-Engineered Valves Feasible? An In Vitro Evaluation Utilizing a Decellularized and Reseeded Biohybrid Valve

Transcatheter aortic valve implantation (TAVI) is a fast-growing, exciting field of invasive therapy. During the last years many innovations significantly improved this technique. However, the prostheses are still associated with drawbacks. The aim of this study was to create cell-seeded biohybrid aortic valves (BAVs) as an ideal implant by combination of assets of biological and artificial materials. Furthermore, the influence of TAVI procedure on tissue-engineered BAV was investigated. BAV (n=6) were designed with decellularized homograft cusps and polyurethane walls. They were seeded with fibroblasts and endothelial cells isolated from saphenous veins. Consecutively, BAV were conditioned under low pulsatile flow (500 mL/min) for 5 days in a specialized bioreactor. After conditioning, TAVI-simulation was performed. The procedure was concluded with re-perfusion of the BAV for 2 days at an increased pulsatile flow (1100 mL/min). Functionality was assessed by video-documentation. Samples were taken after each processing step and evaluated by scanning electron microscopy (SEM), immunohistochemical staining (IHC), and Live/Dead-assays. The designed BAV were fully functioning and displayed physiologic behavior. After cell seeding, static cultivation and first conditioning, confluent cell layers were observed in SEM. Additionally, IHC indicated the presence of endothelial cells and fibroblasts. A significant construction of extracellular matrix was detected after the conditioning phase. However, a large number of lethal cells were observed after crimping by Live/Dead staining. Analysis revealed that the cells while still being present directly after crimping were removed in subsequent perfusion. Extensive regions of damaged cell-layers were detected by SEM-analysis substantiating these findings. Furthermore, increased ICAM expression was detected after re-perfusion as manifestation of inflammatory reaction. The approach to generate biohybrid valves is promising. However, damages inflicted during the crimping process seem not to be immediately detectable. Due to severe impacts on seeded cells, the strategy of living TE valves for TAVI should be reconsidered.

Antithrombotic therapy in patients undergoing TAVI with concurrent atrial fibrillation. One center experience

Aim of the present study was to record the antithrombotic approach in AF and non-AF patients undergoing TAVI, and to compare the efficiency of the used regimens combination. Antithrombotic approach of patients undergoing TAVI remains a challenging dispute. It becomes even more complex when need for anticoagulant treatment is required due to concurrent atrial fibrillation. Consecutive patients with severe symptomatic aortic stenosis treated with TAVI, were retrospectively studied. All patients were divided into two groups, matched to age, depending on the existence of atrial fibrillation. The primary end-point was the composite of MACE, while the secondary end-point was the occurrence of major bleeding at follow-up. A total of 80 patients were included in the study. Out of them, 20 patients (80.2 ± 5.4 years) suffered from concurrent atrial fibrillation. This group was matched with 20 patients (80.6 ± 3.7 years) with no need for anticoagulation. AF-group patients were treated with clopidogrel plus acenocoumarol for 3 months. Following that, acetylsalicylic acid plus acenocoumarol were prescribed. Non-AF patients were treated with 3 months clopidogrel plus acetylsalicylic acid followed by single acetylsalicylic acid medication. No statistical significant differences in MACE between AF and non-AF group were identified (p = 0.705, phi coefficient = 0.06) (mean follow-up 23.4 ± 14 months). Similarly, there was no statistical significant difference for bleedings among the AF and non-AF patient group (p = 0.658, phi coefficient = 0.14). In patients undergoing TAVI with CoreValve, with concurrent AF, treatment with clopidogrel plus acenocoumarol for 3 months, followed by acetylsalicylic acid plus acenocoumarol, seems safe and effective enough in long-term follow-up.

Treatment of acquired von Willebrand syndrome in aortic stenosis with transcatheter aortic valve replacement

OBJECTIVES

This study sought to investigate the prevalence of abnormal von Willebrand multimers (AbM) in patients undergoing transcatheter aortic valve replacement (TAVR) and the impact of TAVR on the underlying factor variances.

BACKGROUND

An association between the acquired von Willebrand syndrome (aVWS) and valvular aortic stenosis (AS) has been established in the past and surgical aortic valve replacement (SAVR) shown to lead to factor recovery. Prevalence and course of AbM in patients treated with TAVR though has not yet been described comprehensively.

METHODS

Ninety-five consecutive patients underwent TAVR at our institution. Hemostaseologic testing was performed before and up to 1 week after TAVR. Transvalvular and right heart hemodynamics as well as bleeding episodes were recorded and analyzed with descriptive statistics.

RESULTS

Baseline prevalence of AbM was 42% with an average high-molecular-weight multimer (HMWM) count of 16.2 ± 3.3%. Pressure gradients correlated significantly with the extent of HMWM deficiency (r = -0.63 [p < 0.0001]). Following valve implantation, HMWM increased proportional to the drop in mean pressure gradient and normalized in most of the patients. However, residual aortic regurgitation/leakage led to inferior HMWM recovery but prosthesis-patient mismatch (PPM) was rare and left HMWM uninfluenced. We saw no association of transfusion with AbM and 1-year mortality was unaffected by AbM.

CONCLUSIONS

AbM in patients with AS undergoing TAVR is frequent. However, TAVR is capable of correcting AbM and therefore possibly aVWS in patients with AS. As opposed to SAVR, bleeding and transfusion requirement in TAVR patients was not associated with severe HMWM deficiency; PPM was rare and HMWM were uninfluenced by the procedure. Aortic regurgitation after TAVR adversely influenced HMWM recovery.

What can be done for cerebral embolic protection in TAVI? Analysis in the light of 10 years' experience with protected carotid artery stenting

In the last 30 years, development of minimally invasive percutaneous procedures to treat cardiovascular defects has been thriving. Although these techniques present obvious advantages, like avoiding cardiopulmonary bypass, the passage of catheter systems and the deployment of devices in the blood circulation can cause particle embolization that may result in stroke. In carotid artery stenting, cerebral embolic protection devices (CEPD) such as filtering membranes have been available for already 10 years. In transcatheter aortic valve implantation (TAVI), the development of CEPD is starting and three membrane-based devices are in clinical trials. There are controversial discussions about the efficacy of CEPD in TAVI. The experience with CEPD in carotid artery stenting can help to understand some of the technical issues and shortcomings of current devices and thereby ultimately reduce cerebral complication risks during TAVI procedures.

Thrombogenic potential of transcatheter aortic valve implantation with trivial paravalvular leakage

BACKGROUND

Significant paravalvular leakage after transcatheter aortic valve implantation (TAVI) correlates with increased morbidity and mortality, but adverse consequences of trivial paravalvular leakage have stimulated few investigations. Using a unique method distinctly different from other diagnostic approaches, we previously reported elevated backflow velocities of short duration (transients) in mechanical valve closure. In this study, similar transients were found in a transcatheter valve paravalvular leakage avatar.

METHODS

Paravalvular leakage rate (zero to 58 mL/second) and aortic valve incompetence (volumetric back flow/forward flow; zero to 32%) were made adjustable using a mock transcatheter aortic valve device and tested in quasi-steady and pulsatile flow test systems. Projected dynamic valve area (PDVA) from the back illuminated mock transcatheter aortic valve device was measured and regional backflow velocities were derived by dividing volumetric flow rate by the PDVA over the open and closing valve phase and the total closed valve area derived from backflow leakage.

RESULTS

Aortic incompetence from 1-32% generated negative backflow transients from 8 to 267 meters/second, a range not dissimilar to that measured in mechanical valves with zero paravalvular leakage. Optimal paravalvular leakage was identified; not too small generating high backflow transients, not too large considering volume overload and cardiac energy loss caused by defective valve behavior and fluid motion.

CONCLUSIONS

Thrombogenic potential of transcatheter aortic valves with trivial aortic incompetence and high magnitude regional backflow velocity transients was comparable to mechanical valves. This may have relevance to stroke rate, asymptomatic microembolic episodes and indications for anticoagulation therapy after transcatheter valve insertion.

Pharmacodynamic effect of clopidogrel in patients undergoing transcatheter aortic valve implantation

The aim of this study was to analyze periprocedural and mid-term effect of clopidogrel on platelet function using the VerifyNow P2Y12 point-of-care assay in patients undergoing TAVI. Platelet reactivity was measured at the beginning of the procedure after 300 mg clopidogrel bolus administration and during the follow-up (at 1 month after the procedure) in 52 patients undergoing TAVI using the Medtronic CoreValve prosthesis (Medtronic CoreValve). A cutoff value of 240 PRU was used to identify nonresponders to clopidogrel treatment with high residual platelet reactivity (HRPR). Baseline HRPR was identified in 80% of patients and in 72% of patients during 6-month follow-up. There was no significant difference in the pharmacodynamic effects of clopidogrel on platelet reactivity from baseline to 6-months follow-up (297 ± 57 vs. 275 ± 62; P = 0.058). Ischemic event occurred only in 3 patients (5.8%) from the study group. In conclusion, majority of patients undergoing TAVI had high residual platelet reactivity after pretreatment with 300 mg of clopidogrel and during the 6-month follow-up at dual antiplatelet treatment. The noneffectiveness of clopidogrel in the TAVI population raises the question of the routine use of dual antiplatelet treatment in this setting.