Early Anticoagulation of Bioprosthetic Aortic Valves in Older Patients

Efficacy and Safety of Edoxaban in Anticoagulant Therapy Early After Surgical Bioprosthetic Valve Replacement: Rationale and Design of the ENBALV Trial

BACKGROUND AND PURPOSE

Anticoagulant therapy with vitamin K antagonists is recommended within 3 to 6 months after bioprosthetic valve replacement to prevent thromboembolic events. However, data regarding whether direct oral anticoagulants can be an alternative to warfarin in such patients are limited. The purpose of this study is to compare the efficacy and safety of edoxaban versus warfarin within 3 months after bioprosthetic valve replacement.

METHODS

The ENBALV trial is an investigator-initiated, phase 3, randomized, open-label, multicenter study. It involves patients aged 18 to 85 years undergoing bioprosthetic valve replacement at the aortic and/or mitral position. They are randomized 1:1 to receive either edoxaban or warfarin. Administration of edoxaban or warfarin is to be continued for 12 weeks after surgery. The primary outcome is the occurrence rate of stroke or systemic embolism at 12 weeks after surgery. The net clinical outcome is a composite of stroke, systemic embolism, or major bleeding, which is included in the secondary outcomes.

CONCLUSION

The ENBALV trial demonstrates the efficacy and safety of edoxaban compared with warfarin in patients early after bioprosthetic valve replacement, including patients with sinus rhythm, which will bring a significant benefit to patients in clinical practice.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCT) 2051210209. 30 Mar 2022 https://jrct.niph.go.jp/latest-detail/jRCT2051210209 .

Comparison of apixaban versus aspirin for the prevention of latent bioprosthetic aortic valve thrombosis: study protocol for a prospective randomized trial

BACKGROUND

The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence. Either oral anticoagulants or acetylsalicylic acid should be considered for the first 3 months. Hypo-attenuated leaflet thickening on cardiac computed tomography has been associated with latent bioprosthetic valve thrombosis and may be prevented with anticoagulation. We hypothesize that anticoagulation with apixaban is superior to single antiplatelet therapy with acetylsalicylic acid in reducing hypo-attenuated leaflet thickening of bioprosthetic aortic valve prostheses.

METHODS

In this prospective, open-label, randomized trial, patients undergoing isolated aortic valve replacement surgery with rapid deployment bioprosthetic valves will be randomized. The treatment group will receive 5 mg of apixaban twice a day for the first 3 months and 100 mg of acetylsalicylic acid thereafter. The control group will be administered 100 mg of acetylsalicylic acid once a day, indefinitely. After the 3-month treatment period, a contrast-enhanced electrocardiogram-gated cardiac computed tomography will be performed to identify hypo-attenuated leaflet thickening of the bioprosthetic valve. The primary objective of the study is to assess the impact of apixaban on the prevention of hypo-attenuated leaflet thickening at 3 months. The secondary and exploratory endpoints will be clinical outcomes and safety profiles of the two strategies.

DISCUSSION

Antithrombotic therapy after aortic valve replacement is used to prevent valve thrombosis and systemic thromboembolism. Latent bioprosthetic valve thrombosis is a precursor of clinically significant prosthetic valve dysfunction or thromboembolic events. The hallmark feature of latent bioprosthetic valve thrombosis is hypo-attenuated leaflet thickening on cardiac computed tomography. Subclinical leaflet thrombosis occurs frequently in bioprosthetic aortic valves, more commonly in transcatheter than in surgical valves. There is no evidence on the effect of direct oral anticoagulants on the incidence of hypo-attenuated leaflet thickening after surgical aortic valve replacement with rapid deployment bioprostheses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06184113. Registered on December 28, 2023.

Thromboembolic and bleeding events after valvular intervention in patients with atrial fibrillation

AIM

To assess outcomes after cardiac surgery with biological valve replacement, valve repair or transcatheter aortic valve implantation (TAVI) in patients with atrial fibrillation (AF) in accordance with oral anticoagulant (OAC) treatment.

METHODS

All patients in Sweden undergoing valvular intervention with AF were included. Associations between OAC exposure and cardiovascular (CV) events (composite of CV death, ischaemic stroke or systemic embolism) and major bleeding were investigated using Cox regression analysis. The analysis was separated in time periods of 0-3 and 3-12 months after discharge.

RESULTS

4730 patients were included in the first time period, 54.0% had received a surgical biological valve prosthesis, 23.8% valve repair and 22.2% TAVI. Exposure to warfarin (comparator) was 62.3%, to non-vitamin K antagonist oral anticoagulants (NOACs) 10.0% and to no OAC 27.7%. NOAC exposure was associated with similar risk of the composite CV outcome and major bleeding from 0 to 3 months. No OAC was associated with increased risk of the composite CV outcome (HR 1.71; 95% CI 1.26 to 2.32) and similar risk of major bleeding. Further analysis of the bioprosthetic valve replacement subgroup indicated increased risk of CV death when exposed to NOAC (HR 2.58; 95% CI 1.15 to 5.78) and no OAC (HR 2.82; 95% CI 1.65 to 4.82) compared with warfarin from 0 to 3 months. No differences were seen between 3 and 12 months.

CONCLUSION

In this registry-based cohort study of patients with AF with severe valvular heart disease undergoing various valvular interventions, NOAC appears to be comparable with warfarin regarding efficacy and safety. Patients not receiving OAC had higher risk of CV events. NOAC was associated with increased CV death compared with warfarin in the surgical bioprosthetic valve replacement subgroup, illustrating the importance of being cautious when extrapolating data from one patient group to another. Further studies comparing NOAC and warfarin in the early postoperative phase are warranted, especially following surgical bioprosthetic valve replacement.

Antithrombotic therapy after heart valve intervention: review of mechanisms, evidence and current guidance

As the population ages and treatment options for heart valve disease increase, the number of patients with intracardiac valve prostheses is growing rapidly. Although all devices have the potential to cause thrombus formation, the propensity depends on the type of prosthesis as well as risk of the individual patient. Mechanical valve prostheses carry the highest (and persistent) risk of thromboembolism, and these patients require anticoagulation with vitamin K antagonists (warfarin). Required international normalised ratio levels are dependent on the location of the valve (mitral>aortic), type of valve (ball and cage vs bilealfet vs On-X bilealfet) and rhythm. The risk of tissue (biological) prosthesis is highest soon after surgery and is dependent on individual patient risk including age, valve location (mitral>aortic), history of thromboembolic events and rhythm. In patients with no other indication for anticoagulation, there is uncertainty on the benefits of anticoagulation versus antiplatelet therapy in patients with tissue prostheses or repaired native valves. Patients with an a priori indication for anticoagulation with a direct oral anticoagulant can continue taking this class of drug. Patients with transcatheter aortic valve implantation devices and no additional evidence-based indication for dual antiplatelet therapy or anticoagulation can be maintained on aspirin monotherapy. Patients undergoing transcatheter instrumentation in the mitral valve position should be anticoagulated, although there is currently no published evidence for antithrombotic management in this group of patients. Patients with thrombosed devices (commonly mitral mechanical) should preferably be treated surgically. Patients at high risk of thromboembolism (with mechanical prostheses) should undergo bridging therapy when undergoing surgery.

Benefit of Anticoagulation Early After Surgical Aortic Valve Replacement Using Bioprosthetic Valves

OBJECTIVE

To compare all-cause mortality and thromboembolic events in patients undergoing surgical aortic valve replacement (sAVR) receiving anticoagulation with warfarin versus patients with no systemic anticoagulation.

PATIENTS AND METHODS

Using data from the OptumLabs Data Warehouse, we investigated adult patients having bioprosthetic sAVR with or without coronary artery bypass from January 1, 2007, through December 31, 2019. Patients were classified into groups of nonwarfarin or warfarin (≥30 days of continuous prescription coverage after sAVR). One-to-one propensity score (PS) matching was used to adjust for group differences.

RESULTS

Of 10,589 patients having sAVR, 7659 (72.3%) were in the nonwarfarin group and 2930 (27.7%) were in the warfarin group. After PS matching, 2930 pairs of patients were analyzed. Median follow-up was 4.1 months (interquartile range [IQR], 2.6-7.4 months) for the warfarin group and 21.3 months (IQR, 7.8-24.0 months) for the nonwarfarin group. Overall mortality was lower for the warfarin group than for the nonwarfarin group (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.47 to 1.00; P=.047), and there was a trend toward decreased cumulative incidence of thromboembolic events (subdistribution HR [SHR], 0.62; 95% CI, 0.35 to 1.07; P=.09). Cumulative incidence of major bleeding events was higher for the warfarin group vs the nonwarfarin group (SHR, 1.94; 95% CI, 1.28 to 2.94; P=.002). Results were similar in a subgroup analysis of patients undergoing isolated sAVR.

CONCLUSION

During the prescription coverage period, warfarin use after bioprosthetic sAVR was associated with lower all-cause mortality and decreased risk of thromboembolism compared with not receiving warfarin. However, warfarin use was associated with an increased risk of major bleeding events.

Anticoagulation After Bioprosthetic Aortic Valve Replacement: Are We Following the Guidelines?

BACKGROUND

Guideline-directed medication adherence is considered an important quality measure after cardiac surgery. We evaluated compliance with the American College of Cardiology/American Heart Association guidelines for warfarin use after surgical aortic valve replacement (sAVR) using bioprostheses and examined potential variations in anticoagulation practice over time.

METHODS

Using the OptumLabs Data Warehouse, we investigated adult patients having bioprosthetic sAVR with or without coronary artery bypass (2007-2019). Early postoperative warfarin use was defined as ≥30 days of continuous prescription coverage after sAVR.

RESULTS

Among 10 730 adult patients having sAVR, 3071 (28.6%) received warfarin early postoperatively. Median length of warfarin prescription coverage was 4.5 months (interquartile range, 3.0-8.9 months). However, only 11.1% (736/6634) had warfarin prescription coverage of 3 to 6 months in compliance with the most recent guidelines. Yearly warfarin prescription rate did not change significantly during the 13-year period (P = .386). Compared with patients from the non-warfarin group, those receiving warfarin prescriptions were older and more likely to be male and to have atrial fibrillation, congestive heart failure, chronic pulmonary disease, and CHA₂DS₂-VASc score ≥2; warfarin use was also greater in patients receiving prescriptions for other cardiac medications (P < .05).

CONCLUSIONS

Anticoagulation after sAVR as reflected by warfarin prescriptions may be underused; the rates of warfarin use have not changed in the last decade. Although additional studies are needed to confirm the benefit of early anticoagulation after sAVR, these results indicate that guideline recommendations are not followed by most clinicians. The findings highlight a potentially important area for quality improvement.

Effects of short-term oral anticoagulation following surgical bioprosthetic aortic valve replacement

BACKGROUND

Short-term oral anticoagulation (OAC) is recommended for patients after surgical bioprosthetic aortic valve replacement (bAVR); however, the potential benefits remain controversial. This study evaluated the effects of short-term OAC following bAVR.

METHODS

From 2010 to 2017, total 450 patients who underwent bAVR were enrolled. The outcomes of patients who did (OAC group) and who did not receive OAC (without-OAC group) after bAVR were compared. Propensity-score matching (PSM) was used to adjust for potential confounders, and a 1:1 matched cohort was formed. The main outcomes were all-cause mortality and bioprosthetic valve dysfunction (BVD).

RESULTS

A total of 175 (39%) patients received OAC after bAVR. The median follow-up period was 2.9 years, the median duration of OAC use was 4 months; 162 pairs of patients were identified after the PSM. There was no significant difference in the prevalence of 1-year embolism/ischemic stroke between the OAC and without-OAC group in PSM cohort (0.62% vs. 1.89% for embolism, p = 0.623; 0 vs. 1.23% for ischemic stroke, p = 0.499). The prevalence of 1-year intracranial hemorrhage (ICH) between OAC and without-OAC group was also comparable (0.62% vs. 0.62%, p = 1). The OAC group had a lower all-cause mortality (adjusted hazard ratio (aHR):0.488, 95% confidence interval (CI): 0.259-0.919). There was also a trend for reduced BVD in the OAC group (aHR: 0.661, 95% CI: 0.339-1.290).

CONCLUSION

Our study demonstrated that short-term OAC use after bAVR was associated with lower all-cause mortality. The prevalence of 1-year embolism/ischemic stroke/ICH were comparable despite of OAC use.

How Did We Get Here? Antithrombotic Therapy after Bioprosthetic Aortic Valve Replacement: A Review

IMPORTANCE

 Aortic stenosis is the most common valvular disease, and more than 90% of patients who undergo aortic valve replacement receive a bioprosthetic valve. Yet optimal antithrombotic therapy after bioprosthetic aortic valve replacement remains uncertain, and guidelines provide contradictory recommendations.

OBSERVATIONS

 Randomized studies of antithrombotic therapy after bioprosthetic aortic valve replacement are small and underpowered. Observational data present opposing, and likely confounded, results. Historically, changes to guidelines have not been informed by high-quality new data. Current guidelines from different professional bodies provide contradictory recommendations despite citing the same evidence.

CONCLUSION

 Insufficient antithrombotic therapy after bioprosthetic aortic valve replacement has serious implications: ischemic stroke, systemic arterial thromboembolism, and clinical and subclinical valve thromboses. Unnecessarily intense antithrombotic therapy, however, increases risk of bleeding and associated morbidity and mortality. Professional bodies have used the current low-quality evidence and generated incongruent recommendations. Researchers should prioritize generating high-quality, randomized evidence evaluating the risks and benefits of antiplatelet versus anticoagulant therapy after bioprosthetic aortic valve replacement.

Early anticoagulation after aortic valve replacement with porcine bioprosthesis randomized control trial (ANTIPRO)

OBJECTIVES

Most evidence for anticoagulation (AC) in aortic bioprosthesis is centred on embolic events, bleeding and reintervention risk. The effect of AC on haemodynamics has not been previously assessed. Our hypothesis was that patients with early AC after aortic valve replacement (AVR) with porcine bioprosthesis have better haemodynamics at 1 year of follow-up.

METHODS

Prospective, randomized, open-label trial conducted at 2 cardiac surgery centres. All patients undergoing AVR with porcine bioprosthesis were consecutively recruited. The anticoagulated group received warfarin + aspirin and the non-anticoagulated (control) only aspirin. The primary outcome was mean gradient after 1 year of AVR and change in New York Heart Association class. Secondary outcomes were major and minor bleeding, embolic events and prosthetic leak.

RESULTS

Of 140 participants in the study, 71 were assigned to the anticoagulated group and 69 to the control group. The mean age of the overall population was 72.4 (SD: 7.1) years. Global EuroSCORE was 7.65 (SD: 5.73). At 1 year, the mean gradient was similar between both groups [18.6 (SD: 1.1 mmHg) and 18.1 (SD: 1.0 mmHg) in the control and anticoagulated groups, respectively, P = 0.701]. No differences in functional class at 3 months or 1 year were found among groups. No differences were found among groups in the secondary outcomes.

CONCLUSIONS

The addition of 3 months of oral AC to anti-aggregation treatment was not detected to affect bioprosthetic haemodynamics nor functional class at 1 year after AVR. Likewise, AC does not lead to the higher incidence of complications.

Structural analysis of regional transcatheter aortic valve underexpansion and its implications for subclinical leaflet thrombosis

Subclinical leaflet thrombosis has been increasingly recognized following transcatheter aortic valve replacement (TAVR). Determining the risk factors is vital in preventing clinical leaflet thrombosis and ensuring long-term value durability. Clinical data have indicated that regional stent under-expansion of transcatheter aortic valves (TAVs), particularly self-expanding devices, may be associated with an increased risk of subclinical leaflet thrombosis. This study aimed to determine the effects of regional TAV frame under-expansion on leaflet kinematics, leaflet structural characteristics, and explore its impact on the likelihood of leaflet thrombosis. In this study, mild and moderate regional frame under-expansion of a 26-mm CoreValve were examined using experimental testing and computational simulations. The results indicated that regional TAV frame under-expansion impairs leaflet kinematics and reduces the range of motion in leaflets with an angle less than 120°. The reduced range of motion can increase blood stasis on the surface of the TAV leaflets. The results also demonstrated that regional frame under-expansion induced localized high-stress regions in the leaflets close to the fixed boundary edge. The increased mechanical stress can lead to accelerated tissue degeneration. The study improves our understanding of the effects of regional stent under-expansion in TAVR. Post-procedural balloon dilatation of self-expanding TAVs can potentially be advantageous in reducing leaflet distortion and normalizing leaflet stress distribution. Large-scale, prospective, and well-controlled studies are needed to further investigate regional TAV frame under-expansion effects on subclinical leaflet thrombosis and long-term valve durability.

Drug Interactions Affecting Oral Anticoagulant Use

Oral anticoagulants (OACs) are medications commonly used in patients with atrial fibrillation and other cardiovascular conditions. Both warfarin and direct oral anticoagulants are susceptible to drug-drug interactions (DDIs). DDIs are an important cause of adverse drug reactions and exact a large toll on the health care system. DDI for warfarin mainly involve moderate to strong inhibitors/inducers of cytochrome P450 (CYP) 2C9, which is responsible for the elimination of the more potent S-isomer of warfarin. However, inhibitor/inducers of CYP3A4 and CYP1A2 may also cause DDI with warfarin. Recognition of these precipitating agents along with increased frequency of monitoring when these agents are initiated or discontinued will minimize the impact of warfarin DDI. Direct oral anticoagulants are mainly affected by medications strongly affecting the permeability glycoprotein (P-gp), and to a lesser extent, strong CYP3A4 inhibitors/inducers. Dabigatran and edoxaban are affected by P-gp modulation. Strong inducers of CYP3A4 or P-gp should be avoided in all patients taking direct oral anticoagulant unless previously proven to be otherwise safe. Simultaneous strong CYP3A4 and P-gp inhibitors should be avoided in patients taking apixaban and rivaroxaban. Concomitant antiplatelet/anticoagulant use confers additive risk for bleeding, but their combination is unavoidable in many cases. Minimizing duration of concomitant anticoagulant/antiplatelet therapy as indicated by evidence-based clinical guidelines is the best way to reduce the risk of bleeding.

Oral anticoagulant treatment after bioprosthetic valvular intervention or valvuloplasty in patients with atrial fibrillation—A SWEDEHEART study

Aims

To describe the prevalence of atrial fibrillation (AF), use of oral anticoagulants (OAC) and change in antithrombotic treatment patterns during follow-up after valve intervention with a biological prosthesis or valvuloplasty.

Methods and results

All patients with history of AF or new-onset AF discharged alive after valvular intervention (biological prosthesis or valvuloplasty) between 2010–2016 in Sweden were included (n = 7,362). Information about comorbidities was collected from national patient registers. Exposure to OAC was based on pharmacy dispensation data. In total 4,800 (65.2%) patients had a history of AF, and 2,562 (34.8%) patients developed new-onset AF, with 999 (39.0%) developing new-onset AF within 3 months after intervention. The proportion of patients with biological valve prosthesis was higher in patients with new-onset AF compared to history of AF (p<0.001). CHA₂DS₂-VASc score ≥2 was observed in 83.1% and 75.5% patients with history of AF and new-onset AF, respectively. Warfarin was more frequently dispensed than NOAC at discharge in patients with history of AF (43.9% vs 7.3%), and in patients with new-onset AF (36.6% vs 17.1%). Almost half of the AF population was not dispensed on any OAC at discharge (48.8% in patients with history of AF and 46.3% in patients with new-onset AF).

Conclusion

In this real world study of patients with AF and recent valvular intervention, risk of new-onset AF after valvular intervention is high emphasizing need for frequent rhythm monitoring after intervention. A considerable undertreatment with OAC was observed despite being indicated for the majority of the patients. Warfarin was the OAC most frequently dispensed.

Incidence of Early Atrial Fibrillation After Transcatheter versus Surgical Aortic Valve Replacement: A Meta-Analysis of Randomized Controlled Trials

Background

Post-operative atrial fibrillation (POAF) is common after aortic valve replacement (AVR) and is associated with worse outcomes. We performed a meta-analysis of randomized controlled trials comparing Surgical Aortic Valve Replacement (SAVR) and Transcatheter Aortic Valve Replacement (TAVR) for incidence of POAF at 30 days.

Methods

We searched databases from 1/1/1990 to 1/1/2020 for randomized studies comparing TAVR and SAVR. POAF was defined as either worsening or new-onset atrial fibrillation. Random effects model was used to estimate the risk of POAF with TAVR vs SAVR in all trials, and in subgroups (low, intermediate, high risk, and in self-expandable vs balloon expandable valves). Sensitivity analysis was performed including only studies reporting new-onset atrial fibrillation.

Results

Seven RCTs were identified that enrolled 7,934 patients (3,999 to TAVR and 3,935 to SAVR). The overall incidence of POAF was 9.7% after TAVR and 33.3% after SAVR. TAVR was associated with a lower risk of POAF compared with SAVR (OR 0.21 [0.18-0.24]; P < 0.0001). Compared with SAVR, TAVR was associated with a significantly lower risk of POAF in the high-risk cohort (OR 0.37 [0.27-0.49]; P < 0.0001), in the intermediate-risk cohort (OR 0.23 [0.19-0.28]; P < 0.0001), low-risk cohort (OR 0.13 [0.10-0.16]; P < 0.0001). Sensitivity analysis of 4 trials including only new-onset POAF showed similar summary estimates (OR 0.21, 95% CI [0.18-0.25]; P< 0.0001).

Conclusions

TAVR is associated with a significantly lower risk of post-operative atrial fibrillation compared with SAVR in all strata. Further studies are needed to identify the contribution of post-operative atrial fibrillation to the differences in clinical outcomes after TAVR and SAVR.

A novel cardiovascular magnetic resonance risk score for predicting mortality following surgical aortic valve replacement

The increasing prevalence of patients with aortic stenosis worldwide highlights a clinical need for improved and accurate prediction of clinical outcomes following surgery. We investigated patient demographic and cardiovascular magnetic resonance (CMR) characteristics to formulate a dedicated risk score estimating long-term survival following surgery. We recruited consecutive patients undergoing CMR with gadolinium administration prior to surgical aortic valve replacement from 2003 to 2016 in two UK centres. The outcome was overall mortality. A total of 250 patients were included (68 ± 12 years, male 185 (60%), with pre-operative mean aortic valve area 0.93 ± 0.32cm², LVEF 62 ± 17%) and followed for 6.0 ± 3.3 years. Sixty-one deaths occurred, with 10-year mortality of 23.6%. Multivariable analysis showed that increasing age (HR 1.04, P = 0.005), use of antiplatelet therapy (HR 0.54, P = 0.027), presence of infarction or midwall late gadolinium enhancement (HR 1.52 and HR 2.14 respectively, combined P = 0.12), higher indexed left ventricular stroke volume (HR 0.98, P = 0.043) and higher left atrial ejection fraction (HR 0.98, P = 0.083) associated with mortality and developed a risk score with good discrimination. This is the first dedicated risk prediction score for patients with aortic stenosis undergoing surgical aortic valve replacement providing an individualised estimate for overall mortality. This model can help clinicians individualising medical and surgical care.

Trial Registration ClinicalTrials.gov Identifier: NCT00930735 and ClinicalTrials.gov Identifier: NCT01755936.

The Prognostic Impact of Anti-thrombotic Treatment Strategies After Biological Aortic Valve Replacement

PURPOSE

Optimal antithrombotic therapy in patients who underwent surgical biological aortic valve replacement (AVR) represents an issue of ongoing discussion. Additionally, the prognostic impact of anti-thrombotic treatment strategies after biological AVR and real-life data on anticoagulation strategies (AC) of patients presenting with short-term postoperative atrial fibrillation (POAF) has not clearly been investigated so far. Therefore, this study aimed to investigate the impact of therapeutic AC after biological AVR on patient outcome and whether the presence of POAF affects decision making on anti-thrombotic management.

METHODS

Within this prospective observational study, 200 individuals that underwent biological AVR surgery were enrolled. Participants were followed prospectively until the primary study endpoint was reached. Multivariate logistic regression analysis was performed to elucidate the effect of therapeutic AC on outcome.

RESULTS

Overall, 106 individuals received therapeutic AC at the time of discharge. The fraction of patients presenting with POAF was balanced between individuals receiving AC and the non-AC subgroup (p = 0.617). After a median follow-up time of 1418 days, 31 (15.5%) individuals died, referring to 15 (13.9%) POAF-free patients and 16 (17.4%) with POAF. We observed a strong inverse association of therapeutic AC and cardiovascular mortality, which remained stable after adjustment for potential confounders showing a HR of 0.437 (95% CI 0.202-0.943; p = 0.035), while bleeding risk was comparable (p = 0.680).

CONCLUSION

Within this investigation, therapeutic AC showed a strong and independent inverse association with long-term mortality in patients that underwent biological AVR. Although POAF is associated with thromboembolic adverse events, the development of this arrhythmia did not affect decision-making of the anti-thrombotic management.

Diagnosis and Treatment of Intracardiac Thrombus

ABSTRACT

Intracardiac thrombi can occur in a variety of locations and are frequently encountered in clinical practice. Yet evidence-based guidance for clinicians managing patients with intracardiac thrombi is often limited. This review summarizes what is known regarding the prevalence of intracardiac thrombus, diagnostic strategies, clinical relevance, and treatment options, focusing on four specific types of thrombus for which recent research has shifted clinical understanding and treatment decisions: (1) left atrial appendage thrombus, (2) cardiac implantable electronic device lead thrombus, (3) bioprosthetic aortic valve thrombus, and (4) left ventricular thrombus. Additional studies, ideally prospective, randomized, and head-to-head in design, are needed to better inform best practices in patients with intracardiac thrombi.

Current Devices and Complications Related to Transcatheter Mitral Valve Replacement: The Bumpy Road to the Top

Mitral regurgitation is the most common valvular lesion in the developed world, with increasing prevalence, morbidity, and mortality. The experience with surgical mitral valve repair or replacement is very well-validated. However, more than 45% of these patients get denied surgery due to an elevated risk profile and advanced disease of the left ventricle at the time of presentation, promoting the need for less invasive transcatheter options such as transcatheter repair and transcatheter mitral valve replacement (TMVR). Early available TMVR studies have shown promising results, and several dedicated devices are under clinical evaluation. However, TMVR is still in the early developmental stages and is associated with a non-negligible risk of periprocedural and post-procedural complications. In this review, we discuss the current challenges facing TMVR and the potential TMVR-related complications, offering an overview on the measures implemented to mitigate these complications, and future implications.

The Characteristics, Long-Term Outcomes, Risk Factors, and Antithrombotic Therapy in Chinese Patients With Atrial Fibrillation and Bioprosthetic Valves

Introduction: There were few data about the clinical profiles and long-term outcomes in Chinese patients with atrial fibrillation (AF) and bioprosthetic valves.

Methods: The retrospective study enrolled 903 patients with bioprosthetic valve replacement at our hospital and discharged with a diagnosis of AF from January 2010 to December 2018.

Results: The median age was 65.6 (61.9–69.1) years, and 548 (60.7%) patients were women. During a follow-up period of 3.84 (2.64–5.51) years, 68 (1.8 per 100 person-years) patients died, 81 (2.1 per 100 person-years) patients developed thromboembolism, and 23 (0.6 per 100 person-years) patients experienced major bleeding. The CHA₂DS₂-VASc score, as a categorical variable (low, moderate, or high risk), predicted the risk of thromboembolism with the C-statistic of 0.6 (95% CI: 0.511–0.689, p = 0.046). The incidence of the CHA₂DS₂-VASc score increment was 11.6 per 100 person-years, and the annual reclassification rate of stroke risk (from a low or moderate group to a higher group) was 12.7%. The current proportion of oral anticoagulants was 52.3, 59, and 63.2%, respectively, in the low, moderate, and high stroke risk groups. Age (OR: 1.04, 95% CI: 1.01–1.06, p = 0.01), left atrial size (OR: 1.05, 95% CI: 1.03–1.08, p < 0.001), and rheumatic heart disease (OR: 1.49, 95% CI: 1.05–2.10, p = 0.025) were positively associated with the use of oral anticoagulants. The history of chronic kidney disease (OR: 0.20, 95% CI: 0.05–0.76, p = 0.018), prior surgical ablation (OR: 0.33, 95% CI: 0.24–0.47, p < 0.001), and antiplatelet agent use (OR: 0.08, 95% CI: 0.05–0.13, p < 0.001) were inversely related to the use of oral anticoagulants. Higher admission estimated glomerular filtration rate (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01), left ventricular ejection fraction (HR: 0.961, 95% CI: 0.931–0.992, p = 0.014), concomitant surgical ablation (HR: 0.348, 95% CI: 0.171–0.711, p = 0.004), and rheumatic heart disease history (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01) were associated with a lower risk of death. Surgical ablation (HR: 0.263, 95% CI: 0.133–0.519, p < 0.001) and oral anticoagulants (HR: 0.587, 95% CI: 0.375–0.918, p = 0.019) were related to a lower risk of thromboembolism.

Conclusion: Chinese patients with AF and bioprosthetic valve(s) were relatively young and had a high prevalence of rheumatic heart disease with few comorbidities. The percentage of mitral bioprosthetic valve replacement was high. The proportion of concomitant surgical ablation or surgical left atrial appendage occlusion or exclusion was relatively low. The thromboembolic events were the major long-term adverse events. The anticoagulation therapy was underused in patients at moderate or high stroke risk. The CHA₂DS₂-VASc score was verified to be used for predicting stroke risk in this population. The stroke risk dynamically changed; it needed to be reestimated once the risk factor changed.

Percutaneous versus Surgical Intervention for Severe Aortic Valve Stenosis: A Systematic Review

Aortic stenosis is a disease that is increasing in prevalence and manifests as decreased cardiac output, which if left untreated can result in heart failure and ultimately death. It is primarily a disease of the elderly who often have multiple comorbidities. The advent of transcatheter aortic valve therapies has changed the way we treat these conditions. However, long-term results of these therapies remain uncertain. Recently, there has been an increasing number of studies examining the role of both surgical aortic valve replacement and transcatheter aortic valve replacement. We therefore performed a systematic review using Ovid MEDLINE, Ovid Embase, and the Cochrane Library. Two investigators searched papers published between January 1, 2007, and to date using the following terms: "aortic valve stenosis," "aortic valve operation," and "transcatheter aortic valve therapy." Both strategies in aortic stenosis treatment highlighted specific indications alongside the pitfalls such as structural valve degeneration and valve thrombosis which have a bearing on clinical outcomes. We propose some recommendations to help clinicians in the decision-making process as technological improvements make both surgical and transcatheter therapies viable options for patients with aortic stenosis. Finally, we assess the role of finite element analysis in patient selection for aortic valve replacement. THVT and AVR-S are both useful tools in the armamentarium against aortic stenosis. The decision between the two treatment strategies should be best guided by a strong robust evidence base, ideally with a long-term follow-up. This is best performed by the heart team with the patient as the center of the discussion.

Fifty years of the pericardial valve: Long-term results in the aortic position

It is now 50 years since the development of the first pericardial valve in 1971. In this time significant progress has been made in refining valve design aimed at improving the longevity of the prostheses. This article reviews the current literature regarding the longevity of pericardial heart valves in the aortic position. Side by side comparisons of freedom from structural valve degeneration are made for the valves most commonly used in clinical practice today, including stented, stentless, and sutureless valves. Strategies to reduce structural valve degeneration are also discussed including methods of tissue fixation and anti-calcification, ways to minimise mechanical stress on the valve, and the role of patient prosthesis mismatch.

Variation in Antithrombotic Therapy and Clinical Outcomes in Patients With Preexisting Atrial Fibrillation Undergoing Transcatheter Aortic Valve Replacement: Insights From the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry

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Antithrombotic Therapy for Stroke Patients with Cardiovascular Disease

Prevention of ischemic stroke relies on the use of antithrombotic medications comprising antiplatelet agents and anticoagulation. Stroke risk is particularly high in patients with cardiovascular disease. This review will focus on the role of antithrombotic therapies in the context of different types of cardiovascular disease. We will discuss oral antiplatelet medications and both IV and parental anticoagulants. Different kinds of cardiovascular disease contribute to stroke via distinct pathophysiological mechanisms, and the optimal treatment for each varies accordingly. We will explore the mechanism of stroke and evidence for antithrombotic therapy in the following conditions: atrial fibrillation, prosthetic heart values (mechanical and bioprosthetic), aortic arch atherosclerosis, congestive heart failure (CHF), endocarditis (infective and nonbacterial thrombotic endocarditis), patent foramen ovale (PFO), left ventricular assist devices (LVAD), and extracorporeal membrane oxygenation (ECMO). While robust data exist for antithrombotic use in conditions such as atrial fibrillation, optimal treatment in many situations remains under active investigation.

Risks and benefits of concurrent treatment with antiplatelet and anticoagulation therapy in post-op bioprosthetic aortic valve replacement patients

BACKGROUND AND AIM

Among patients receiving surgical bioprosthetic aortic valve replacement (bAVR), there is an elevated risk of thromboembolic events postoperatively. However, the risks and benefits of varying anticoagulation strategies remain controversial. The aim of this study is to compare the risks and benefits of aspirin monotherapy to aspirin plus warfarin ("concurrent therapy") in patients receiving bAVR.

METHODS

A retrospective cohort study was conducted using patients' data from Kaiser Permanente Northern California, including those who underwent bAVR with or without coronary artery bypass grafting between 2009 and 2018. Patients were identified as having been discharged with aspirin only or concurrent therapy. The outcomes were mortality, thromboembolic events, and clinically relevant bleeding during a 6-month follow-up. The event rates were compared using the Kaplan-Meier method. Multivariable survival analysis, incorporating propensity scores, was used to estimate adjusted hazard ratios (aHRs) for each outcome.

RESULTS

The cohort consisted of 3047 patients. Approximately 58% of patients received aspirin only and 42% received concurrent therapy. Patients who received concurrent therapy were more likely to be older, have hypertension, previous stroke, and longer hospital stays. After adjustment using multivariable analysis, concurrent therapy was associated with a higher risk of clinically relevant bleeding (aHR, 2.33; 95% confidence interval, 1.67-3.25). There was no significant difference in the risk of thromboembolic events or mortality between the two groups.

CONCLUSION

Patients who underwent bAVR and were discharged on concurrent therapy compared to aspirin only had a significantly increased risk of bleeding without a significant difference in thromboembolic events.

A randomized clinical trial to evaluate the efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valve and atrial fibrillation or flutter: Rationale and design of the RIVER trial

The efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valves and atrial fibrillation or flutter remain uncertain. DESIGN: RIVER was an academic-led, multicenter, open-label, randomized, non-inferiority trial with blinded outcome adjudication that enrolled 1005 patients from 49 sites in Brazil. Patients with a bioprosthetic mitral valve and atrial fibrillation or flutter were randomly assigned (1:1) to rivaroxaban 20 mg once daily (15 mg in those with creatinine clearance <50 mL/min) or dose-adjusted warfarin (target international normalized ratio 2.0-30.); the follow-up period was 12 months. The primary outcome was a composite of all-cause mortality, stroke, transient ischemic attack, major bleeding, valve thrombosis, systemic embolism, or hospitalization for heart failure. Secondary outcomes included individual components of the primary composite outcome, bleeding events, and venous thromboembolism. SUMMARY: RIVER represents the largest trial specifically designed to assess the efficacy and safety of a direct oral anticoagulant in patients with bioprosthetic mitral valves and atrial fibrillation or flutter. The results of this trial can inform clinical practice and international guidelines.

Anticoagulation and antiplatelet therapy in patients with prosthetic heart valves

BACKGROUND

The choice of antithrombotic therapy, anticoagulants or antiplatelets, after prosthetic heart valve replacement or repair, remains a disputed topic in the literature. Antithrombotic therapies are used after heart valve intervention to reduce the rates of thromboembolic events, therefore improving patient outcomes. Different interventions may require different therapeutic regimens to achieve the most efficacious clinical outcome for patients.

METHODS AND DISCUSSION

This review aims to summarize and critique the available literature concerning therapeutic agents used for bioprosthetic and mechanical valves as well as for valve repair, so as to assist clinicians and researchers in making decisions with regard to their patients and research endeavors.

Nonusefulness of Antithrombotic Therapy After Surgical Bioprosthetic Aortic Valve Replacement

Controversy persists regarding the advisability of anticoagulation for the early period after biological surgical aortic valve replacement (AVR). We aim to examine the impact of various antithrombotic regimens on outcomes in a large cohort of biological AVR patients. Records of 1,111 consecutive adult patients who underwent surgical biological AVR at our institution between 2013 and 2017 were reviewed. Outcomes included stroke, bleeding, and death at 3 and 12 months. Treatment regimens included (1) no therapy, (2) anticoagulants (warfarin or Factor Xa inhibitors), (2) antiplateles (various), and (4) anticoagulants + antiplatelets. Kaplan-Meier analysis was used to track outcomes, and Cox-proportional hazards regression models were conducted to analyze effects of different therapies on adverse events. At 3 months, thromboembolic events were low and not significantly different between the no therapy group (2.2%) and anticoagulation (2.8%) or anticoagulation + antiplatelet (3.6%) or all groups (3.7%). The antiplatelet group was just significantly lower, at 2.2%. However, this was driven by non-stroke cardiovascular events in patients with coronary artery disease. The incidence of death at 3 months was low and not significantly different between all groups. At 12 months, there were no thromboembolic benefits between groups, but bleeding events were significantly higher in the anticoagulation group (no therapy (1.4%), anticoagulation (8.4%), antiplatelet (4.5%), anticoagulation + antiplatelet (7.9%)). In conclusion, none of the antithrombotic regimens showed benefits in stroke or survival at 3 or 12 months after biological AVR. Anticoagulation increased bleeding events. Routine anticoagulation after biological AVR appears to be unnecessary and potentially harmful.

The Beneficial Effect of Anticoagulation in Aortic Bioprosthesis is Associated with its Size

OBJECTIVE

To evaluate the clinical and echocardiographic outcomes in aortic valve replacement (AVR) patients with aortic bioprosthesis under oral anticoagulation (OA).

METHODS

Patients who underwent AVR with bioprosthesiswere prospectively enrolled. They were classified based on postoperative use of OA. Clinical and operative variables were collected. Echocardiographic and clinical follow-ups were performed two years after surgery. The primary outcome evaluated was change in transprosthetic gradient. Secondary outcomes analyzed were change in New York Heart Association (NYHA) class, major bleeding episodes, hospitalization, stroke, and transient ischemic attack.

RESULTS

We included 103 patients (61 without OA and 42 with OA). Clinical characteristics were similar among groups, except for younger age (76±6.3 vs. 72.4±8.1 years, P=0.016) and higher prevalence of atrial fibrillation (0% vs. 23.8%, P<0.001) in the OA group. Mean (21.4±10 mmHg vs. 16.8±7.7 mmHg, P=0.037) and maximum (33.4±13.7 mmHg vs. 28.4±10.2 mmHg, P=0.05) transprosthetic gradients were higher in patients without OA. Improvement in NYHA class was more frequent in patients with OA (73% vs. 45.3%, P=0.032). Major bleeding, stroke, and hospitalization were similar among groups. OA was the only independent predictor for improvement of NYHA class after multivariate logistic regression analysis (odds ratio [OR]: 5.9, 95% confidence interval [CI]: 1.2-29.4; P=0.028). Stratification by prosthesis size showed that patients with ≤ 21 mm prosthesis benefited from OA.

CONCLUSION

Early anticoagulation after AVR with bioprosthesis was associated with significant decrease of transprosthesis gradient and improvement in NYHA class. These associations were seen mainly in patients with ≤ 21 mm prosthesis.

Anticoagulation After Surgical or Transcatheter Bioprosthetic Aortic Valve Replacement

BACKGROUND

There is paucity of evidence on the impact of anticoagulation (AC) after bioprosthetic aortic valve replacement (AVR) on valve hemodynamics and clinical outcomes.

OBJECTIVES

The study aimed to assess the impact of AC after bioprosthetic AVR on valve hemodynamics and clinical outcomes.

METHODS

Data on antiplatelet and antithrombotic therapy were collected. Echocardiograms were performed at 30 days and 1 year post-AVR. Linear regression model and propensity-score adjusted cox proportional model were used to assess the impact of AC on valve hemodynamics and clinical outcomes, respectively.

RESULTS

A total of 4,832 patients undergoing bioprosthetic AVR (transcatheter aortic valve replacement [TAVR], n = 3,889 and surgical AVR [SAVR], n = 943) in the pooled cohort of PARTNER2 (Placement of Aortic Transcatheter Valves) randomized trials and nonrandomized registries were studied. Following adjustment for valve size, annular diameter, atrial fibrillation, and ejection fraction at the time of assessment of hemodynamics, there was no significant difference in aortic valve mean gradients or aortic valve areas between patients discharged on AC vs. those not discharged on AC, for either TAVR or SAVR cohorts. A significantly greater proportion of patients not discharged on AC had an increase in mean gradient >10 mm Hg from 30 days to 1 year, compared with those discharged on AC (2.3% vs. 1.1%, p = 0.03). There was no independent association between AC after TAVR and adverse outcomes (death, p = 0.15; rehospitalization, p = 0.16), whereas AC after SAVR was associated with significantly fewer strokes (hazard ratio [HR]: 0.17; 95% confidence interval [CI]: 0.05-0.60; p = 0.006).

CONCLUSIONS

In the short term, early AC after bioprosthetic AVR did not result in adverse clinical events, did not significantly affect aortic valve hemodynamics (aortic valve gradients or area), and was associated with decreased rates of stroke after SAVR (but not after TAVR). Whether early AC after bioprosthetic AVR has impact on long-term outcomes remains to be determined. (Placement of AoRTic TraNscathetER Valves [PARTNERII A]; NCT01314313).

Comparison of warfarin versus antiplatelet therapy after surgical bioprosthetic aortic valve replacement

Objectives

To compare effectiveness of warfarin and antiplatelet exposure regarding both thrombotic and bleeding events, following surgical aortic valve replacement with a biological prosthesis(bioSAVR).

Methods

The study included all patients in Sweden undergoing a bioSAVR during 2008–2014 who were alive at discharge from the index hospital stay. Exposure was analysed and defined as postdischarge dispension of any antithrombotic pharmaceutical, updated at each following dispensions and categorised as single antiplatelet (SAPT), warfarin, warfarin combined with SAPT, dual antiplatelet (DAPT) or no antithrombotic treatment. Exposure to SAPT was used as comparator. Outcome events were all-cause mortality, ischaemic stroke, haemorrhagic stroke, any thromboembolism and major bleedings. We continuously updated adjustments for comorbidities with any indication for antithrombotic treatment by Cox regression analysis.

Results

We identified 9539 patients with bioSAVR (36.8% women) at median age of 73 years with a mean follow-up of 3.13 years. As compared with SAPT, warfarin alone was associated with a lower incidence of ischaemic stroke (HR 0.49, 95% CI 0.35 to 0.70) and any thromboembolism (HR 0.75, 95% CI 0.60 to 0.94) but with no difference in mortality (HR 0.94, 95% CI 0.78 to 1.13). The incidence of haemorrhagic stroke (HR 1.94, 95% CI 1.07 to 3.51) and major bleeding (HR 1.67, 95% CI 1.30 to 2.15) was higher during warfarin exposure. As compared with SAPT, DAPT was not associated with any difference in ischaemic stroke or any thromboembolism. Risk-benefit analyses demonstrated that 2.7 (95% CI 1.0 to 11.9) of the ischaemic stroke cases could potentially be avoided per every haemorrhagic stroke caused by warfarin exposure instead of SAPT during the first year.

Conclusion

In patients discharged after bioSAVR, warfarin exposure as compared with SAPT exposure was associated with lower long-term risk of ischaemic stroke and thromboembolic events, and with a higher incidence of bleeding events but with similar mortality.

Non-vitamin K oral anticoagulant use after cardiac surgery is rapidly increasing

OBJECTIVE

The prevalence of non-vitamin K oral anticoagulant use after cardiac surgery is unknown, particularly in patients with bioprosthetic valves. We sought to define the contemporary use and short-term safety of non-vitamin K oral anticoagulants after cardiac surgery.

METHODS

All patients undergoing bioprosthetic aortic valve replacement, bioprosthetic mitral valve replacement, or isolated coronary artery bypass grafting (2011-2018) were evaluated from a multicenter, regional Society of Thoracic Surgeons database. Patients were stratified by anticoagulant type (non-vitamin K oral anticoagulant vs vitamin K antagonist) and era (early [2011-2014] vs contemporary [2015-2018]).

RESULTS

Of 34,188 patients, 18% (6063) were discharged on anticoagulation, of whom 23% were prescribed non-vitamin K oral anticoagulants. Among those receiving anticoagulation, non-vitamin K oral anticoagulant use has significantly increased from 10.3% to 35.4% in contemporary practice (P < .01). This trend was observed for each operation type (coronary artery bypass grafting 0.86%/year, bioprosthetic aortic valve replacement: 2.15%/year, bioprosthetic mitral valve replacement: 2.72%/year, all P < .01). In patients with postoperative atrial fibrillation receiving anticoagulation, non-vitamin K oral anticoagulant use has increased from 6.3% to 35.4% and 12.3% to 40.3% after bioprosthetic valve replacement and isolated coronary artery bypass grafting, respectively (both P < .01). In patients receiving anticoagulation at discharge, adjusted 30-day mortality (odds ratio, 1.94; P = .12) and reoperation (odds ratio, 0.79; P = .34) rates were not associated with anticoagulant choice, whereas non-vitamin K oral anticoagulant use was associated with an adjusted 0.9-day decrease (P < .01) in postoperative length of stay.

CONCLUSIONS

Non-vitamin K oral anticoagulant use after cardiac surgery has dramatically increased since 2011. This trend is consistent regardless of indication for anticoagulation including bioprosthetic valves. Short-term outcomes support their safety in the cardiac surgery setting with shorter postoperative hospital stays. Long-term studies on the efficacy of non-vitamin K oral anticoagulants after cardiac surgery are still necessary.

Association Between Antithrombotic Medication Use After Bioprosthetic Aortic Valve Replacement and Outcomes in the Veterans Health Administration System

Importance

The recommendations about antithrombotic medication use after bioprosthetic aortic valve replacement (bAVR) vary.

Objectives

To describe the post-bAVR antithrombotic medication practice across the Veterans Health Administration (VHA) and to assess the association between antithrombotic strategies and post-bAVR outcomes.

Design, Setting, and Participants

Retrospective cohort study. Multivariable modeling with propensity scores was conducted to adjust for differences in patient characteristics across the 3 most common antithrombotic medication strategies (aspirin plus warfarin sodium, aspirin only, and dual antiplatelets). Text mining of notes was used to identify the patients with bAVR (fiscal years 2005-2015).

Main Outcomes and Measures

This study used VHA and non-VHA outpatient pharmacy data and text notes to classify the following antithrombotic medications prescribed within 1 week after discharge from the bAVR hospitalization: aspirin plus warfarin, aspirin only, dual antiplatelets, no antithrombotics, other only, and warfarin only. The 90-day outcomes included all-cause mortality, thromboembolism risk, and bleeding events. Outcomes were identified using primary diagnosis codes from emergency department visits or hospital admissions.

Results

The cohort included 9060 veterans with bAVR at 47 facilities (mean [SD] age, 69.3 [8.8] years; 98.6% male). The number of bAVR procedures per year increased from 610 in fiscal year 2005 to 1072 in fiscal year 2015. The most commonly prescribed antithrombotic strategy was aspirin only (4240 [46.8%]), followed by aspirin plus warfarin (1638 [18.1%]), no antithrombotics (1451 [16.0%]), dual antiplatelets (1010 [11.1%]), warfarin only (439 [4.8%]), and other only (282 [3.1%]). Facility variation in antithrombotic prescription patterns was observed. During the 90-day post-bAVR period, adverse events were uncommon, including all-cause mortality in 127 (1.4%), thromboembolism risk in 142 (1.6%), and bleeding events in 149 (1.6%). No differences in 90-day mortality or thromboembolism were identified across the 3 antithrombotic medication groups in either the unadjusted or adjusted models. Patients receiving the combination of aspirin plus warfarin had higher odds of bleeding than patients receiving aspirin only in the unadjusted analysis (odds ratio, 2.58; 95% CI, 1.71-3.89) and after full risk adjustment (adjusted odds ratio, 1.92; 95% CI, 1.17-3.14).

Conclusions and Relevance

These data demonstrate that bAVR procedures are increasingly being performed in VHA facilities and that aspirin only was the most commonly used antithrombotic medication strategy after bAVR. The risk-adjusted results suggest that the combination of aspirin plus warfarin does not improve either all-cause mortality or thromboembolism risk but increases the risk of bleeding events compared with aspirin only.

Follow-up and management of valvular heart disease patients with prosthetic valve: a clinical practice guideline for Indian scenario

PURPOSE

Valvular heart disease (VHD) patients after prosthetic valve implantation are at risk of thromboembolic events. Follow-up care of patients with prosthetic valve has a paramount role in reducing the morbidity and mortality. Currently, in India, there is quintessential need to stream line the follow-up care of prosthetic valve patients. This mandates the development of a consensus guideline for the antithrombotic therapy in VHD patients post prosthetic valve implantation.

METHODS

A national level panel was constituted comprising 13 leading cardio care experts in India who thoroughly reviewed the up to date literature, formulated the recommendations, and developed the consensus document. Later on, extensive discussions were held on this draft and the recommendations in 8 regional meetings involving 79 additional experts from the cardio care in India, to arrive at a consensus. The final consensus document is developed relying on the available evidence and/or majority consensus from all the meetings.

RESULTS

The panel recommended vitamin K antagonist (VKA) therapy with individualized target international normalized ratio (INR) in VHD patients after prosthetic valve implantation. The panel opined that management of prosthetic valve complications should be personalized on the basis of type of complications. In addition, the panel recommends to distinguish individuals with various co-morbidities and attend them appropriately.

CONCLUSIONS

Anticoagulant therapy with VKA seems to be an effective option post prosthetic valve implantation in VHD patients. However, the role for non-VKA oral therapy in prosthetic valve patients and the safety and efficacy of novel oral anticoagulants in patients with bioprosthetic valve need to be studied extensively.

Bioprosthetic Valve Thrombosis

Degenerative valve disease is on the rise with greater than 100,000 valve operations performed in the US alone per year. The majority of those procedures employ tissue bioprostheses to avoid the attendant risk of anticoagulation, especially in the elderly. Though traditionally this approach has been considered a superior option to avoid anticoagulation, more recent analyses have demonstrated a significant incidence of previously unrecognized thrombosis associated with bioprosthetic valves, especially with the more recent advent of the transcatheter aortic valve replacement implantations. Bioprosthetic valve thrombosis is a major cause of either acute or indolent bioprosthetic valve degeneration, and often has an elusive presentation causing delayed recognition and treatment. The literature has extensively addressed the risks and benefits of anticoagulation following bioprosthetic valve replacement to prevent bioprosthetic valve thrombosis (BPVT), without conclusive evidence-based recommendations. The duration of anticoagulation following an episode of BPVT is unclear, and lifelong anticoagulation has been suggested. The increasing use of transcatheter aortic valve replacement as an alternative to surgical aortic valve replacement in various risk groups has introduced new challenges with regards to valve thrombosis, which have been poorly studied with regards to optimal treatment and prevention. The increasing use of valve-in-valve procedures is expected to bring on further uncharted challenges.