Antithrombotic treatment in patients undergoing transcatheter aortic valve implantation (TAVI)

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.

The search for optimal antithrombotic therapy in transcatheter aortic valve implantation: facts and uncertainties

Transcatheter aortic valve implantation (TAVI) is a minimally invasive procedure, which is used frequently in patients with symptomatic severe aortic valve stenosis. Most patients undergoing TAVI are over 80 years of age with a high bleeding as well as thrombotic risk. Despite the increasing safety of the procedure, thromboembolic events [stroke, (subclinical) valve thrombosis] remain prevalent. As a consequence, antithrombotic prophylaxis is routinely used and only recently new data on the efficacy and safety of antithrombotic drugs has become available. On the other hand, these antithrombotic drugs increase bleeding in a population with unique aortic stenosis-related bleeding characteristics (such as acquired von Willebrand factor defect and angiodysplasia). In this review, we discuss the impact of thromboembolic and bleeding events, the current optimal antithrombotic therapy based on registries and recent randomized controlled trials, as well as try to give a practical guide how to treat these high-risk patients. Finally, we discuss knowledge gaps and future research needed to fill these gaps.

Cerebral Protection in TAVR-Can We Do Without? A Real-World All-Comer Intention-to-Treat Study-Impact on Stroke Rate, Length of Hospital Stay, and Twelve-Month Mortality

Background: Stroke associated with transcatheter aortic valve replacement (TAVR) is a potentially devastating complication. Until recently, the Sentinel™ Cerebral Protection System (CPS; Boston Scientific, Marlborough, MA, USA) has been the only commercially available device for mechanical prevention of TAVR-related stroke. However, its effectiveness is still undetermined. Objectives: To explore the impact of Sentinel™ on stroke rate, length of hospital stay (LOS), and twelve-month mortality in a single-center, real-world, all-comers TAVR cohort. Material and Methods: Between January 2019 and August 2020 consecutive patients were assigned to TAVR with or without Sentinel™ in a 1:1 fashion according to the treating operator. We defined as primary endpoint clinically detectable cerebrovascular events within 72 h after TAVR and as secondary endpoints LOS and 12-month mortality. Logistic and linear regression analyses were used to assess associations of Sentinel™ use with endpoints. Results: Of 411 patients (80 ± 7 y/o, 47.4% female, EuroSCORE II 6.3 ± 5.9%), Sentinel™ was used in 213 (51.8%), with both filters correctly deployed in 189 (46.0%). Twenty (4.9%) cerebrovascular events were recorded, ten (2.4%) of which were disabling strokes. Patients with Sentinel™ suffered 71% less (univariate analysis; OR 0.29, 95%CI 0.11–0.82; p = 0.02) and, respectively, 76% less (multivariate analysis; OR 0.24, 95%CI 0.08–0.76; p = 0.02) cerebrovascular events compared to patients without Sentinel™. Sentinel™ use was also significantly associated with shorter LOS (Regression coefficient −2.47, 95%CI −4.08, −0.87; p < 0.01) and lower 12-month all-cause mortality (OR 0.45; 95%CI 0.22–0.93; p = 0.03). Conclusion: In the present prospective all-comers TAVR cohort, patients with Sentinel™ use showed (1) lower rates of cerebrovascular events, (2) shortened LOS, and (3) improved 12-month survival. These data promote the use of a CPS when implanting TAVR valves.

Non-vitamin K antagonist oral anticoagulants in patients with valvular heart disease

The non-vitamin K antagonist oral anticoagulants (NOACs) dabigatran, rivaroxaban, apixaban, and edoxaban have transformed the management of atrial fibrillation (AF), but are only approved by regulatory authorities for stroke prophylaxis in patients with so-called "non-valvular AF." This terminology has spawned confusion about which patients with valvular heart disease benefit from NOACs and which should be treated with vitamin K antagonists (VKAs) instead. Patients with valvular heart disease other than mechanical prosthetic valves or severe mitral stenosis (including those with bioprosthetic valves) were included in pivotal trials demonstrating the benefit of NOACs over VKAs, and consensus guidelines recommend NOACs over VKAs in these patients. Subsequent devoted randomized controlled trials in patients with AF and bioprosthetic valves, including transcatheter valves, have confirmed the safety of NOACs in this population. In patients with rheumatic mitral stenosis, observational studies indicate that NOACs may be safe and effective, but randomized controlled trials are ongoing. By contrast, a randomized controlled trial showed that dabigatran is harmful in patients with mechanical prosthetic mitral valves; however, these data may not extrapolate to patients with mechanical valve prostheses in other locations or to other NOACs, and randomized controlled trials are ongoing. In this review, we discuss these data in greater depth, and make recommendations for the use of NOACs in patients with valvular heart disease.

Transcatheter aortic valve implantation induces transient drop in platelet reactivity

ABSTRACT

Although recent studies described platelet reactivity (PR) changes in days following transcatheter aortic valve implantation (TAVI), precise time course and duration of these changes have not been fully investigated. The aim of this study was to investigate PR pattern during and after TAVI in multiple time points. Study included 40 consecutive patients undergoing TAVI. All patients underwent the procedure on dual antiplatelet therapy. PR was measured in seven time points: before induction of anaesthesia (T1), after heparin administration (T2), 10 minutes after initial valve implantation (T3), at the end of procedure (T4), and on 3rd, 6th and 30th postoperative day (T 5-7). PR was measured using impedance aggregometer using three different platelet aggregation agonists (arachidonic acid in ASPItest, adenosine diphosphate in ADPtest and thrombin receptor activating peptide 6 in TRAPtest). All patients underwent successful TAVI procedure. Mean PR on T1 was 22.9±23.0 U for ASPItest, 40.5±23.7 U for ADPtest and 91.7±32.5 U for TRAPtest. There was no significant difference in PR on T2. On T3, significant reduction of PR in all three tests was observed (ASPI 10.4±11.6 U (p=0.001), ADP 24.2±14.1 U (p<0.001) and TRAP 69.3±26.6 U (p<0.001)). PR nadir for all tests was reached on T5, with subsequent PR incline. PR values in all tests returned to baseline levels on T7. Our results show that successful TAVI procedure induces transient decrease in PR regardless of the platelet activation pathway.

Transcatheter mitral valve thrombosis: A case report and literature review

Transcatheter mitral valve replacement (TMVR) is an exciting alternative therapy for complex patients with mitral valve disease. Experience with TMVR is new and there is a lot yet to discover about their durability, long-term outcomes, and complications including mitral transcatheter heart valve (THV) thrombosis. Many factors have been speculated to increased risk of THV thrombosis. Here, we report a case of a 72-year-old woman who developed mitral THV thrombosis after undergoing TMVR for severe mitral regurgitation with mitral annular calcification. We reviewed 42 TMVR papers with 1,484 patients, including 60 with mitral THV thrombosis. We discussed the most common strategies used for mitral THV thromboprophylaxis and treatment.

Effect of Instruction on Preventing Delayed Bleeding after Colorectal Polypectomy and Endoscopic Mucosal Resection

Background: The frequency of delayed bleeding after colorectal polypectomy has been reported as 0.6–2.8%. With the increasing performance of polypectomy under continuous use of antithrombotic agents, care is required regarding delayed post-polypectomy bleeding (DPPB). Better instruction to educate endoscopists is therefore needed. We aimed to evaluate the effect of instruction and factors associated with delayed bleeding after endoscopic colorectal polyp resection. Methods: This single-center, retrospective study was performed to assess instruction in checking complete hemostasis and risk factors for onset of DPPB. The incidence of delayed bleeding, comorbidities, and medications were evaluated from medical records. Characteristics of historical control patients and patients after instruction were compared. Results: A total of 3318 polyps in 1002 patients were evaluated. The control group comprised 1479 polyps in 458 patients and the after-instruction group comprised 1839 polyps in 544 patients. DPPB occurred in 1.1% of polyps in control, and 0.4% in after-instruction. Instruction significantly decreased delayed bleeding, particularly in cases with antithrombotic agents. Hot polypectomy, clip placement, and use of antithrombotic agents were significant independent risk factors for DPPB even after instruction. Conclusion: The rate of delayed bleeding significantly decreased after instruction to check for complete hemostasis. Even after instruction, delayed bleeding can still occur in cases with antithrombotic agents or hot polypectomy.

Usefulness of Clopidogrel Loading in Patients Who Underwent Transcatheter Aortic Valve Implantation (from the BRAVO-3 Randomized Trial)

P2Y₁₂-inhibitor initiation with clopidogrel using a loading dose (LD) versus no LD (NLD) provides more rapid inhibition of platelet activation and reduced risk of ischemic events after coronary stenting. Whether a similar beneficial effect is achieved in the setting of transcatheter aortic valve implantation (TAVI) is unknown. We evaluate the effects of preprocedural clopidogrel LD versus no NLD on 48-hour and 30-day clinical outcomes after TAVI. In the BRAVO-3 trial, 802 patients with severe aortic stenosis who underwent transfemoral TAVI were randomized to intraprocedural anticoagulation with bivalirudin or unfractionated heparin. Administration of clopidogrel LD was left to the discretion of the treating physician. For this analysis, patients were stratified according to receiving clopidogrel LD (n = 294, 36.6%) or NLD (n = 508, 63.4%) before TAVI. LD patients more often received a self-expandable prosthesis using larger sheaths. P2Y₁₂-inhibitor maintenance therapy pre-TAVI was similar in patients with LD versus NLD (28.2% vs 33.1%, p = 0.16). LD versus NLD was associated with similar incidences of major adverse cardiovascular events (i e., death, myocardial infarction, or stroke) (4.1% vs 4.1%, p = 0.97) and major bleeding (8.5% vs 7.7%, p = 0.68), but a higher rate of major vascular complications (11.9% vs 7.1%, p = 0.02). Multivariable adjustment showed that clopidogrel LD did not affect any of the studied clinical events, including major vascular complications (odds ratio 0.91, 95% confidence interval 0.60 to 1.39, p = 0.67). Also patients on clopidogrel maintenance therapy and thus considered in steady state were not at reduced risk of major adverse cardiovascular events compared with patients not on clopidogrel (3.7% vs 5.2%, p = 0.36). In conclusion, in patients who underwent TAVI, use of clopidogrel LD was associated with higher vascular complications and otherwise similar clinical events compared to NLD patients.

Edoxaban Versus standard of care and their effects on clinical outcomes in patients having undergone Transcatheter Aortic Valve Implantation in Atrial Fibrillation-Rationale and design of the ENVISAGE-TAVI AF trial

Transcatheter aortic valve implantation, also called transcatheter aortic valve replacement (TAVR), is the treatment of choice for patients with severe aortic stenosis and intermediate to high operative risk. A significant portion of TAVR patients have atrial fibrillation (AF) requiring chronic oral anticoagulation. In moderate- to high-risk AF patients, the direct factor Xa inhibitor edoxaban is noninferior to vitamin K antagonists (VKAs) for prevention of stroke or systemic embolism with less bleeding and cardiovascular deaths. ENVISAGE-TAVI AF (NCT02943785) is a multinational, multicenter, prospective, randomized, open-label, blinded end point evaluation study comparing edoxaban to VKA-based therapy in approximately 1,400 patients with an indication for chronic oral anticoagulation after successful transfemoral TAVR. The coprimary end points are to assess the differential effects of the 2 treatments (a) on net adverse clinical events (the composite of all-cause death, myocardial infarction, ischemic stroke, systemic thromboembolism, valve thrombosis, and major bleeding events) and (b) on major bleeding. Twelve hours to 5 days after successful TAVR, patients will be randomized to 60 mg daily oral edoxaban or any VKA (international normalized ratio: 2.0-3.0 or 1.6-2.6 [numbers inclusive] in Japan if age ≥ 70 years). Antiplatelet therapy may be administered per physician's discretion. Randomization will be stratified by edoxaban dose reduction (per local label). Treatment duration will be up to 36 months. The study is powered (80%) to detect noninferiority (margin for the hazard ratio: 1.38) for the composite primary end points, followed by superiority testing.

Antiplatelet therapy combined with acenocoumarol in relation to major bleeding, ischaemic stroke and mortality

BACKGROUND

Vascular disease is a frequent comorbidity in atrial fibrillation (AF) patients, resulting in concomitant use of antiplatelet therapy. In the present study, we investigated the incidence and risk of major bleeding, ischaemic stroke, and mortality in a cohort of AF patients taking acenocoumarol plus antiplatelet therapy, in comparison with AF patients taking only acenocoumarol monotherapy.

METHODS

We consecutively included 1361 "real-world" AF patients stable for at least the previous 6 months on acenocoumarol (INR 2.0-3.0). The primary endpoint was major bleeding defined using the 2005 International Society on Thrombosis and Haemostasis (ISTH) criteria. As secondary endpoints, we analysed ischaemic strokes and all-cause mortality. During follow-up, all adverse events were recorded and compared within patients taking acenocoumarol plus antiplatelet therapy and patients taking only acenocoumarol.

RESULTS

During 6.5 years (IQR 4.3-7.9) of follow-up, there were 250 (2.83%/year) bleeds, 130 (1.47%/year) ischaemic strokes and 511 (6.23%/year) deaths. After multivariate Cox regression analyses, combined antithrombotic therapy was associated with major bleeding (HR 1.40, 95% CI 1.01-1.94; P = .048), but not lower mortality (HR 0.95, 95% CI 0.75-1.21; P = .674) or ischaemic stroke (HR 1.45, 95% CI 0.97-2.17; P = .072).

CONCLUSIONS

In AF patients, the risk of bleeding is higher when antiplatelet therapy is combined with acenocoumarol, but the risk of mortality and stroke was not significantly different from that of patients taking only acenocoumarol.

Gene polymorphisms in dual antiplatelet therapy and the presence of hypo-attenuated leaflet thickening after transcatheter aortic valve replacement

The imaging finding of hypo-attenuated leaflet thickening (HALT) on bioprosthesis after transcatheter aortic valve replacement (TAVR) has been reported. The underlying mechanism is not clear, but leaflet thrombosis is speculated to be the cause. Heterogeneous antiplatelet responses may play a role in the process. This is a prospective, single-center pilot study in patients who received successful TAVR from June 2012 to November 2016. HALT on post-procedural multi-detector computed tomography. We thoroughly genotyped 34 SNPs and 8 SNPs that have been reported for clopidogrel and aspirin resistance. A total of 148 patients were enrolled. There were 15 patients demonstrating signs of HALT. Patients with HALT had a higher rate of atrial fibrillation (AF) pre-TAVR (33.3 vs. 7.5%, P = 0.01). We found that rs4244285 G>A polymorphism of the CYP2C19 gene was associated with the risk of HALT in the overdominant model (OR 4.00 [1.15-13.97], P = 0.02 for GA vs. GG+AA) adjusted by sex and the presence of pre-TAVR AF. Antiplatelet drug resistance is a reasonable possibility involved in HALT. Potential directions were suggested in polymorphisms of the CYP2C19 gene.

Recent advances in understanding and managing aortic stenosis

Over the last few years, treatment of severe symptomatic aortic stenosis in high-risk patients has drastically changed to adopt a less-invasive approach. Transcatheter aortic valve implantation (TAVI) has been developed as a very reproducible and safe procedure, as shown in many trials. When compared to surgery, TAVI has produced superior, or at least comparable, results, and thus a trend to broaden treatment indications to lower-risk patients has erupted as a natural consequence, even though there is a lack of long-term evidence. In this review, we summarize and underline aspects that still remain unanswered that are compulsory if we want to enhance our understanding of this disease.

Adjuvant Antithrombotic Therapy in TAVR

PURPOSE OF REVIEW

Transcatheter aortic valve replacement (TAVR) has developed into an important alternative to surgical aortic valve replacement (SAVR) for patients with severe aortic stenosis (AS). Adjuvant antithrombotic therapies are commonly used during and after TAVR to decrease the risk of valve thrombosis and thromboembolic cerebrovascular events (CVEs) but consequently increase the risk of bleeding. This article reviews the past and current clinical data regarding adjuvant antithrombotic therapies in TAVR.

RECENT FINDINGS

Cerebrovascular and bleeding events during and after TAVR are associated with substantial morbidity and mortality. Bivalirudin, a direct thrombin inhibitor, has been shown to be safe alternative to unfractionated heparin (UFH) as procedural anticoagulation during TAVR; however, sparse evidence exists to guide use of antiplatelet and anticoagulant therapies in patients after TAVR. Multiple studies comparing different antithrombotic regimens in the post-TAVR setting are currently underway. Current guidelines recommend intra-procedural anticoagulation with UFH for during TAVR and with dual antiplatelet therapy (DAPT) after TAVR. There is a need to better understand the role of adjuvant antithrombotic therapies in TAVR. The results of ongoing studies are needed to develop evidence-based guidance for the use of adjuvant antithrombotic therapies after TAVR.

Spotlight on unmet needs in stroke prevention: The PIONEER AF-PCI, NAVIGATE ESUS and GALILEO trials

Atrial fibrillation (AF) is a major healthcare concern, being associated with an estimated five-fold risk of ischaemic stroke. In patients with AF, anticoagulants reduce stroke risk to a greater extent than acetylsalicylic acid (ASA) or dual antiplatelet therapy (DAPT) with ASA plus clopidogrel. Non-vitamin K antagonist oral anticoagulants (NOACs) are now a widely-accepted therapeutic option for stroke prevention in non-valvular AF (NVAF). There are particular patient types with NVAF for whom treatment challenges remain, owing to sparse clinical data, their high-risk nature or a need to harmonise anticoagulant and antiplatelet regimens if co-administered. This article focuses on three randomised controlled trials (RCTs) that are investigating the utility of rivaroxaban, a direct, oral, factor Xa inhibitor, in additional areas of stroke prevention where data for anticoagulants are lacking: oPenlabel, randomized, controlled, multicentre study explorIng twO treatmeNt stratEgiEs of Rivaroxaban and a dose-adjusted oral vitamin K antagonist treatment (PIONEER AF-PCI); New Approach riVaroxoban Inhibition of factor Xa in a Global trial vs Aspirin to prevenT Embolism in Embolic Stroke of Undetermined Source (NAVIGATE ESUS); and Global study comparing a rivAroxaban-based antithrombotic strategy to an antipLatelet-based strategy after transcatheter aortIc vaLve rEplacement to Optimize clinical outcomes (GALILEO). Data from these studies present collaborative efforts to build upon existing registrational Phase III data for rivaroxaban, driving the need for effective and safe treatment of a wider range of patients for stroke prevention.

Routine use of anticoagulation after transcatheter aortic valve replacement: Initial safety outcomes from a single-center experience

BACKGROUND

Subclinical leaflet thrombosis (SCLT) can be seen in up to 12% of patients after transcatheter aortic valve replacement (TAVR). Anticoagulation appears to prevent and reverse SCLT but concerns exist about bleeding risk.

METHODS

Our program adopted a strategy of routine anticoagulation after TAVR, starting warfarin on post-procedure day 0 and continuing for 3months in 10/2015. We report the initial safety and efficacy outcomes of this approach. Bleeding events were assessed using Valve Academic Research Consortium (VARC) and Bleeding Academic Research Consortium (BARC) definitions.

RESULTS

The median (IQR) age of the population (n=191) was 82years (72-87) and the median (IQR) STS score was 5.6% (3-8). A total of 101 (53%) patients were discharged on anticoagulation (warfarin 97%) while 90 (47%) received antiplatelet therapy alone. The mean duration of anticoagulation therapy was 81±17 days. During follow-up 7 patients (4%) had a stroke or TIA, 3 (3%) in the anticoagulation group and 4 (4%) in the antiplatelet group (p=0.71). A total of 8 patients (4.2%) had BARC bleeding events during follow-up, 3 patients in the anticoagulation group (2.9%) and 5 in the antiplatelet group (5.5%, p=0.48). All bleeding events (VARC and BARC) were numerically lower in the anticoagulation group (8% versus 13%, p=0.20).

CONCLUSIONS

A strategy of routine anticoagulation for 3-months after TAVR is well tolerated and associated with similar or lower bleeding risk compared to antiplatelet therapy.

Dual Versus Single Antiplatelet Regimen With or Without Anticoagulation in Transcatheter Aortic Valve Replacement: Indirect Comparison and Meta-analysis

INTRODUCTION AND OBJECTIVES

There is uncertainty on the correct management of antithrombotic therapies after transcatheter aortic valve replacement (TAVR), with dual antiplatelet therapy (DAPT) being currently recommended on an empirical basis. The aim of the present meta-analysis was to assess the safety and effectiveness of DAPT in patients undergoing TAVR.

METHODS

Studies comparing different antithrombotic regimens after TAVR were included. The primary endpoint was 30-day overall mortality.

RESULTS

We included 9 studies, 5 comparing DAPT with aspirin monotherapy and 4 comparing DAPT with monoantiplatelet therapy (MAPT) + oral anticoagulation. Among 7991 patients, 72% were on DAPT. The median follow-up was 3.5 months. Mortality was significantly lower in the DAPT group (12.2% vs 14.4%; OR, 0.81; 95%CI, 0.70-0.93; P = .003; P_het = .93), with similar benefits compared with aspirin monotherapy (OR, 0.80; 95%CI, 0.69-0.93; P = .004; P_het = .60), which were not statistically significant when compared with MAPT + oral anticoagulation (OR, 0.86; 95%CI, 0.55-1.35; P = .51; P_het = .97). A similar trend for DAPT was observed for stroke (OR, 0.83 95%CI, 0.63-1.10; P = .20; P_het = .67), with no increase in the rate of major bleedings (OR, 1.69; 95%CI, 0.86-3.31; P = .13; P_het< .0001). On indirect comparison analysis, no benefit in survival, stroke, or bleedings was identified for additional oral anticoagulation.

CONCLUSIONS

The present meta-analysis supports the use of DAPT after TAVR, reducing mortality and offering slight benefits in stroke, with no increase in major bleedings compared with MAPT. The strategy of aspirin + oral anticoagulation did not provide significant benefits compared with MAPT or DAPT.

Late Obstructive Transcatheter Heart Valve Thrombosis Resolved by Rivaroxaban

Patient: Male, 68

Final Diagnosis: Transcatheter heart valve thrombosis

Symptoms: None

Medication: —

Clinical Procedure: —

Specialty: Cardiology

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.

[TAVI in Germany. What have we learned from current studies?]

Transcatheter aortic valve implantation (TAVI) has become an established treatment for symptomatic aortic valve stenosis in inoperable patients and high-risk patients. In Germany the TAVI procedure has now surpassed the annual numbers of isolated surgical aortic valve replacement with a recent trend towards treatment of intermediate-risk patients; however, before TAVI can also be used in patients with lower surgical risk, studies are required to demonstrate the safety and efficacy of this method for this patient population.

Thrombolytic Therapy as the Management of Mitral Transcatheter Valve-in-Valve Implantation Early Thrombosis

A 70-year-old male underwent mitral transcatheter valve-in-valve implantation for a failed bioprosthesis implanted 11 years earlier. In the first days following the procedure, he developed thrombosis of the new bioprosthesis with restricted cusp motion. The transmitral mean gradient increased significantly despite effective anticoagulation therapy using unfractionated heparin infusion. Low dose and slow infusion of alteplase resulted in resolution of the thrombus and normalisation of cusp motion. Thereafter long-term anticoagulation using a vitamin K antagonist was instituted and the patient remained asymptomatic.