Thirty-year outcomes of low-intensity anticoagulation for mechanical aortic valve

The long-term safety, efficacy, and outcomes of low-intensity anticoagulation for mechanical heart valves remain unclear. This study aimed to evaluate the long-term outcomes of low-intensity anticoagulation therapy after aortic valve replacement (AVR) with a mechanical prosthesis. This retrospective cohort study consulted medical records and conducted a questionnaire to investigate 519 patients who underwent single AVR with the St. Jude Medical bileaflet valve and were in sinus rhythm. All patients were followed up with an international normalized ratio (INR) target of 1.6-2.5, and their INR values were checked throughout the follow-up period. The survival rate, incidence of major adverse cardiac and cerebrovascular events (MACCE), and risk factors for cardiac death and MACCE were investigated. The total follow-up was 9793 patient-years, and the follow-up periods were 19.9 (standard deviation [SD]: 7.9) years. The mean INR was 2.03 (SD: 0.54). Survival rates from cardiac death were 93.6% in 20 years and 85.2% in 30 years. Advanced age ≥ 70 years was the only significant risk factor for cardiac death and MACCE, and the INR < 2.0 was not significant risk factor for MACCE including thromboembolism or bleeding events. Low-intensity anticoagulation with an INR of 1.6-2.5 for patients with sinus rhythm after AVR with a bileaflet mechanical valve is safe and effective, even over 30 years.

On-X aortic valve replacement patients treated with low-dose warfarin and low-dose aspirin

OBJECTIVES

To assess if warfarin targeted to international normalized ratio (INR) 1.8 (range 1.5-2.0) is safe for all patients with an On-X aortic mechanical valve.

METHODS

This prospective, observational registry follows patients receiving warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus daily aspirin (75-100 mg) after On-X aortic valve replacement. The primary end point is a composite of thromboembolism, valve thrombosis and major bleeding. Secondary end points include the individual rates of thromboembolism, valve thrombosis and major bleeding, as well as the composite in subgroups of home or clinic-monitored INR and risk categorization for thromboembolism. The control was the patient group randomized to standard-dose warfarin (INR 2.0-3.0) plus daily aspirin 81 mg from the PROACT trial.

RESULTS

A total of 510 patients were enroled at 23 centres in the UK, USA and Canada. Currently, the median follow-up duration is 3.4 years, and median achieved INR is 1.9. The primary composite end point rate in the low INR patients is 2.31% vs 5.39% (95% confidence interval 4.12-6.93%) per patient-year in the PROACT control group, constituting a 57% reduction. Results are consistent in subgroups of home or clinic-monitored, and high-risk patients, with reductions of 56%, 57% and 57%, respectively. Major and total bleeding are decreased by 85% and 73%, respectively, with similar rates of thromboembolic events. No valve thrombosis occurred.

CONCLUSIONS

Interim results suggest that warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus aspirin is safe and effective in patients with an On-X aortic mechanical valve with or without home INR monitoring.

Low-dose warfarin with a novel mechanical aortic valve: Interim registry results at 5-year follow-up

OBJECTIVES

To evaluate whether warfarin targeted at an international normalized ratio of 1.8 (range, 1.5-2.0) after On-X mechanical aortic valve implant is safe for all patients.

METHODS

This prospective, observational clinical registry assessed adverse event rates in adult patients receiving low-dose warfarin (target international normalized ratio, 1.8; range, 1.5-2.0) plus daily aspirin (75-100 mg) during a 5-year period after On-X aortic valve implant. The primary end point is the combined rate of major bleeding, valve thrombosis, and thromboembolism overall and in 4 subgroups. The comparator is the Prospective Randomized On-X Anticoagulation Trial control group patients on standard-dose warfarin (international normalized ratio, 2.0-3.0) plus aspirin 81 milligrams daily.

RESULTS

A total of 510 patients were recruited at 23 centers in the United States, United Kingdom, and Canada between November 2015 and January 2022. This interim analysis includes 229 patients scheduled to complete 5-year follow-up by August 16, 2023. The linearized occurrence rate (in percent per patient-year) of the primary composite end point of major bleeding, valve thrombosis, and thromboembolism is 1.83% compared with 5.39% (95% confidence interval, 4.12%-6.93%) in the comparator group. Results are consistent in clinic-monitored and home-monitored patients and in those at high risk for thromboembolism. Major bleeding and total bleeding were reduced by 87% and 71%, respectively, versus the comparator group, without an increase in thromboembolic events.

CONCLUSIONS

Interim results support the continued safety of the On-X aortic mechanical valve with a target international normalized ratio of 1.8 plus low-dose aspirin through 5 years after implant, with or without home monitoring.

Application of eHealth Tools in Anticoagulation Management After Cardiac Valve Replacement: Scoping Review Coupled With Bibliometric Analysis

BACKGROUND

Anticoagulation management can effectively prevent complications in patients undergoing cardiac valve replacement (CVR). The emergence of eHealth tools provides new prospects for the management of long-term anticoagulants. However, there is no comprehensive summary of the application of eHealth tools in anticoagulation management after CVR.

OBJECTIVE

Our objective is to clarify the current state, trends, benefits, and challenges of using eHealth tools in the anticoagulation management of patients after CVR and provide future directions and recommendations for development in this field.

METHODS

This scoping review follows the 5-step framework developed by Arksey and O'Malley. We searched 5 databases such as PubMed, MEDLINE, Web of Science, CINAHL, and Embase using keywords such as "eHealth," "anticoagulation," and "valve replacement." We included papers on the practical application of eHealth tools and excluded papers describing the underlying mechanisms for developing eHealth tools. The search time ranged from the database inception to March 1, 2023. The study findings were reported according to the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews). Additionally, VOSviewer (version 1.6.18) was used to construct visualization maps of countries, institutions, authors, and keywords to investigate the internal relations of included literature and to explore research hotspots and frontiers.

RESULTS

This study included 25 studies that fulfilled the criteria. There were 27,050 participants in total, with the sample size of the included studies ranging from 49 to 13,219. The eHealth tools mainly include computer-based support systems, electronic health records, telemedicine platforms, and mobile apps. Compared to traditional anticoagulation management, eHealth tools can improve time in therapeutic range and life satisfaction. However, there is no significant impact observed in terms of economic benefits and anticoagulation-related complications. Bibliometric analysis suggests the potential for increased collaboration and opportunities among countries and academic institutions. Italy had the widest cooperative relationships. Machine learning and artificial intelligence are the popular research directions in anticoagulation management.

CONCLUSIONS

eHealth tools exhibit promise for clinical applications in anticoagulation management after CVR, with the potential to enhance postoperative rehabilitation. Further high-quality research is needed to explore the economic benefits of eHealth tools in long-term anticoagulant therapy and the potential to reduce the occurrence of adverse events.

Safety and efficacy of using portable coagulation monitor for INR examination after left-sided mechanical prosthetic valve replacement

BACKGROUND

Time in therapeutic range (TTR) is an index to assess the effectiveness of anticoagulation and is important to predict the risk of bleeding and thrombosis in patients taking warfarin. In recent years, the portable coagulation monitor, a point-of-care testing device for patients to perform self-management international normalized ratio (INR) examination, has provided an opportunity to improve the quality of oral warfarin treatment. In this study, we applied TTR to evaluate the safety and efficacy of the portable coagulation monitor for patients with oral anticoagulant warfarin after left-sided mechanical prosthetic valve (MPV) replacement.

METHODS

It is a single-centre cohort study. From September 2019 to June 2021, a total of 243 patients who returned to our institution for outpatient clinic revisit at 3 months after left-sided MPV replacement, met the inclusion criteria and agreed to be followed up were included. Self-management group used portable coagulation monitor for INR examination, and patients in the conventional group had their INR monitored in routine outpatient visits. Clinical data of the patients would be recorded for the next 12 months, and results were compared between the two groups to assess the effect of the coagulation monitor on TTR and complications related to bleeding and thrombosis in patients with left-sided MPV replacement.

RESULTS

A total of 212 individuals provided complete and validated INR data spanning of 1 year. Those who applied the portable coagulation monitor had higher TTR values and larger number of tests for INR. No significant differences were seen between the two groups in postoperative bleeding and thromboembolic complications, but portable coagulation monitor showed a trend toward fewer bleeding events.

CONCLUSION

Portable devices for coagulation monitoring are safe and can achieve a higher TTR. Patients who use the portable coagulation monitor for home INR self-management can achieve a safe and effective warfarin therapy.

Clinical Features and Survival Analysis of Patients after Mechanical Heart Valve Replacement, with an Emphasis on Prosthetic Valve Thrombosis

BACKGROUND

Valvular heart diseases are highly prevalent in the world, and surgical valve replacement has improved patients' survival.

OBJECTIVES

To describe clinical and laboratory data of patients undergoing mechanical valve replacement, and to determine the incidence of prosthetic valve thrombosis (PVT).

METHODS

Retrospective cohort study with a follow-up of up to nine years. The study variables were collected from conventional and electronic medical charts. Statistical calculations were performed using the Jamovi software version 1.2.2.; a p<0.05 was considered statistically significant. Kaplan Meier curves were constructed, and Cox regression analysis was performed for analysis of factors related to mortality.

RESULTS

A total of 473 patients were included, mean age of 46.9 ±11.3 years. Rheumatic disease was the most common etiology. In a mean follow-up period of 4.43 years, mortality rate was 16.1%. Patients with aortic prosthesis showed higher survival than patients with double implant (mitral and aortic) (p=0.026). Of the factors adjusted for mortality, only functional class and chronic renal failure showed statistically significant association. The incidence of PVT was 0.24/100 patients/year, and the first event occurred more than 1000 days after the implant. Smoking and pannus formation were significantly associated with PVT. No differences were found in INR variability between patients with and without thrombosis by prosthetic position, but significant differences were found in INR before thrombosis as compared with patients without thrombosis (INR= 2.20 [1.80-2.20] vs. 2.80 [2.20-3.40]; p= 0.040). The incidence of stroke and bleeding was 4.4% and 5.2% respectively.

CONCLUSIONS

The study population was young, and rheumatic valve disease was common in this group. The prevalence of PVT was similar to that described in the literature, despite the low income and low educational level of our sample.

Combining portable coagulometers with the Internet: A new model of warfarin anticoagulation in patients following mechanical heart valve replacement

Heart valve replacement, as a safe and effective treatment for severe valvular heart disease, can significantly improve hemodynamics in patients. However, such patients then require lifelong anticoagulant therapy. Warfarin, a cheap and highly effective vitamin K antagonist, remains the major anticoagulant recommended for lifelong use following mechanical heart valve replacement. However, the effect of warfarin anticoagulant therapy is complicated by physiological differences among patients and non-compliance with treatment at different degrees. Effective management of warfarin therapy after heart valve replacement is currently an important issue. Portable coagulometers and the emergence of the Internet have provided new opportunities for long-term management of anticoagulation therapy, but the safety and affordability of this approach remain to be fully evaluated. This paper reviews recent progress on the use of portable coagulometers and the Internet in the management of warfarin anticoagulation therapy following mechanical heart valve replacement, which offers opportunities for reducing complications during postoperative anticoagulation and for facilitating patient compliance during follow-up.

Efficacy and safety of low intensity vitamin K antagonists in Western and East-Asian patients with left-sided mechanical heart valves

The optimal INR target in patients with mechanical heart valves is unclear. Higher INR targets are often used in Western compared with East Asian countries. The objective of this systematic review and meta-analysis was to summarize the evidence for the efficacy and safety of lower versus higher INR targets in Western and East Asian left-sided mechanical heart valve patients. We searched Western databases including Cochrane CENTRAL, Medline, and Embase as well as Chinese databases including SinoMed, CNKI, and Wanfang Data in addition to grey literature for Randomized Controlled Trials (RCTs) and observational studies. We pooled risk ratios (RRs) using random-effects model. Low and high INR targets were defined by the individual studies. We identified nine RCTs, including six Western (n = 5496) and three East Asian (n = 209) trials, and 17 observational studies, including two Western (n = 3199) and 15 East Asian (n = 5485) studies. In the RCTs, lower compared with higher targets were associated with similar rates of thromboembolism (2.4 vs. 2.3%; RR: 1.14, 95% CI 0.82, 1.60, I² = 0%) and lower rates of both total bleeding (21.9 vs. 40.9%, RR: 0.46, 95% CI 0.28, 0.78, I² = 88%) and major bleeding. RCT data showed no statistical heterogeneity by region. These effects were consistent in the observational data. We downgraded the quality of evidence due to serious risk of bias and imprecision. In patients with left-sided contemporary mechanical heart valves, low quality evidence suggests lower INR targets are associated with similar rates of thromboembolism and moderate quality evidence suggests lower rates of bleeding.

Self-management of patients with heart valve replacement and its clinical outcomes: a systematic review

Introduction

For patients with heart valve replacement, self-management can play an essential role in the management of their condition.

Aim

This review aimed to identify the aspects of self-management and its clinical outcomes in patients with heart valve replacement.

Material and methods

In this systematic review, the peer-reviewed research literature on self-management of patients with heart valve replacement was assessed. Since May 2020, the PubMed, Scopus, and web of science databases were searched regardless of time and language limitations. The eligibility of the articles was assessed by title or abstract according to the search strategy. Article selection was applied regarding to inclusion and exclusion criteria. Also, article screening was conducted by 2 independent authors.

Results

Twenty-five studies were considered in this systematic review. For inclusion, the self-management of patients had to have prerequisites, appropriate training, and be applicable in the aspects of anticoagulation therapy self-management, international normalized ratio (INR) self-testing, low-dose INR self-management, and heart valve function self-monitoring. In this method, through proper management of INR levels and anticoagulation therapy, the complications rate could be reduced and the patients would be able to diagnose functional disorders in the early stages by monitoring the valve function. This procedure was able to prevent the progression of complications.

Conclusions

Self-management is an applicable protocol in the field of anticoagulation therapy, INR control, low-dose INR management, and the monitoring of cardiac valve function. This protocol could improve the quality of treatment for these patients through upgrading the care standards.

Antithrombotic Treatment After Surgical and Transcatheter Heart Valve Repair and Replacement

New antithrombotic drugs have been developed, new valve types have been designed and minimally invasive transcatheter techniques have emerged, making the choice of antithrombotic therapy after surgical or transcatheter heart valve repair and replacement increasingly complex. Moreover, due to a lack of large randomized controlled trials many recommendations for antithrombotic therapy are based on expert opinion, reflected by divergent recommendations in current guidelines. Therefore, decision-making in clinical practice regarding antithrombotic therapy for prosthetic heart valves is difficult, potentially resulting in sub-optimal patient treatment. This article compares the 2017 ESC/EACTS and 2020 ACC/AHA guidelines on the management of valvular heart disease and summarizes the available evidence. Finally, we established a convenient consensus on antithrombotic therapy after valve interventions based on over 800 annual cases of surgical and transcatheter heart valve repair and replacement and a multidisciplinary team discussion between the department of cardiovascular diseases and cardiac surgery of the University Hospitals Leuven, Belgium.

Transcatheter aortic valve implantation in low-risk patients: A case of rational over exuberance. The time is not now

BACKGROUND

Review of evidence and concerns, relating to extension of transcatheter aortic valve implantation usage to low-risk patients.

METHODS

Comprehensive literature review was conducted identifying articles relating to transcatheter aortic valve implantation.

RESULTS

Transcatheter aortic valve implantation is effective in patients with aortic stenosis. Currently, long-term durability and cost-effectiveness are unproven, anticoagulation requirement undefined, permanent pacemaker implantation and paravalvular leak rates higher than following surgical aortic valve replacement.

CONCLUSIONS

Current evidence supporting transcatheter aortic valve implantation usage in low-risk patients is insufficient. Extending use now, to this large young patient population is premature, and should be delayed.

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.

Is it safe and effective to reduce the target anticoagulation range for patients with mechanical prosthetic aortic valves?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Is it safe and effective to reduce the target anticoagulation range for patients with mechanical aortic valves?' Altogether 922 papers were found using the reported search, of which 7 represented the best evidence to answer the clinical question. Only studies that compared high (target international normalized ratio 2-3) versus low (target international normalized ratio <2-3) intensity anticoagulation were included. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that there is growing evidence for the reduction of the target anticoagulation range for patients with mechanical prosthetic aortic valves, especially bileaflet valves with presumed better haemodynamic properties. Several large randomized controlled trials and a meta-analysis have concluded that reducing the target international normalized ratio range (below the conventional range of 2-3) for mechanical aortic valves in patients with no thrombogenic risk factors produces less bleeding and does not increase thromboembolic events.

How Did We Get Here?: A Historical Review and Critical Analysis of Anticoagulation Therapy Following Mechanical Valve Replacement

Managing severe valvular heart disease with mechanical valve replacement necessitates lifelong anticoagulation with a vitamin K antagonist. Optimal anticoagulation intensity for patients with mechanical valves remains uncertain; current recommendations are inconsistent across guideline bodies and largely based on expert opinion. In this review, we outline the history of anticoagulation therapy in patients with mechanical heart valves and critically evaluate current antithrombotic guidelines for these patients. We conclude that randomized trials evaluating optimal anticoagulation intensity in patients with mechanical valves are needed, and that future guidelines must better justify antithrombotic treatment recommendations.

Clinical outcomes and hospital readmission rates in mechanical vs bioprosthetic mitral valves

OBJECTIVE

Recent national trends have demonstrated increased use of bioprosthetic mitral valves. The primary objective of this study was to compare clinical outcomes as well as readmission rates for mechanical vs bioprosthetic mitral valve replacement (mMVR vs bMVR).

METHODS

All patients undergoing MVR from 2011-2017 were included in a single center data set that was obtained retrospectively from a prospectively maintained cardiac surgical database.

RESULTS

The total MVR patient cohort consisted of 828 patients, including bMVR (n = 522) and mMVR (n = 306). There was no significant difference in the operative (30-day) mortality between bMVR and mMVR (8.6% vs 6.5%; P = .31). The unadjusted estimated 1-year mortality was significantly higher for the bMVR group (19.8% vs 13.7%, P = .04) and this trend continued for the estimated 5-year mortality (35.1% vs 18.7%; P = .001). Valve prosthesis choice (bMVR vs mMVR) did not have a risk-adjusted impact on operative mortality at 30 days (P = .58); however 1-year (P = .05) and 5-year (P = .05) mortality remained significantly higher for the bMVR group. Propensity matching revealed a higher mortality rate on follow-up in the bMVR (26.7% vs 18.2%, P = .03) but no difference at 30 days or 1 year. There was no difference in hospital readmissions over 5 years CONCLUSIONS: Mechanical prostheses may confer a survival benefit in patients undergoing MVR. With emphasis on patient education and anticoagulation compliance, mMVR remains an efficacious option.

Predictors of anticoagulation quality in 15 834 patients performing patient self-management of oral anticoagulation with vitamin K antagonists in real-life practice: a survey of the International Self-Monitoring Association of Orally Anticoagulated Patients

Although patient self-management (PSM) of oral anticoagulation with vitamin K antagonists is recommended for patients requiring long-term anticoagulation, important aspects are still unclear. Using data from a large international survey (n = 15 834; median age 72 years; 30·1% female), we studied predictors of poor anticoagulation control (percentage of International Normalized Ratio values within therapeutic range below 75%) and developed a simple prediction model. The following variables were identified as risk factors for poor anticoagulation control and included in the final model: higher intensity of therapeutic range (odds ratio [OR] on every level 1·9; 95% confidence interval [CI] 1·8-2·0), long intervals between measurements (>14 d; 1·5; 95% CI 1·3-1·7), female sex (OR 1·3; 95% CI 1·2-1·4), and management other than PSM (OR 1·4; 95% CI 1·2-1·6). At a threshold of 0·2 (at least one variable present), the model predicted poor anticoagulation control with a sensitivity of 85·3% (95% CI: 84·0, 86·4) and a specificity of 28·5% (27·6, 29·5). The area under the receiver operated characteristic curve was 0·65. Using the proposed prediction model, physicians will be able to identify patients with a low chance of performing well, considering additional training, regular follow-up, or adjustment of therapeutic ranges.

Cardiac surgery 2015 reviewed

For the year 2015, almost 19,000 published references can be found in PubMed when entering the search term "cardiac surgery". The last year has been again characterized by lively discussions in the fields where classic cardiac surgery and modern interventional techniques overlap. Lacking evidence in the field of coronary revascularization with either percutaneous coronary intervention or bypass surgery has been added. As in the years before, CABG remains the gold standard for the revascularization of complex stable triple-vessel disease. Plenty of new information has been presented comparing the conventional to transcatheter aortic valve implantation (TAVI) demonstrating similar short- and mid-term outcomes at high and low risk, but even a survival advantage with transfemoral TAVI at intermediate risk. In addition, there were many relevant and interesting other contributions from the purely operative arena. This review article will summarize the most pertinent publications in the fields of coronary revascularization, surgical treatment of valve disease, heart failure (i.e., transplantation and ventricular assist devices), and aortic surgery. While the article does not have the expectation of being complete and cannot be free of individual interpretation, it provides a condensed summary that is intended to give the reader "solid ground" for up-to-date decision-making in cardiac surgery.

Self-Management of Anticoagulant Therapy in Mechanical Heart Valve Patients: A Matched Cohort Study

BACKGROUND

Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists for mechanical heart valves has demonstrated efficacy in randomized controlled trials. However, the effectiveness of PSM in clinical practice has only been investigated in small trials. Our aim was to evaluate the effectiveness of PSM of oral anticoagulant therapy in mechanical heart valve patients.

METHODS

We conducted a matched cohort study: cases were patients with a mechanical heart valve performing PSM affiliated with Aarhus University Hospital or Aalborg University Hospital, Denmark, in the period 1996 to 2012 (n = 615). Prospectively registered patient data were obtained from databases at two hospitals, and cross linkage between these databases and national patient registries provided detailed information on comorbidities and events. Control patients were matched (on sex, date of birth, year of first valve surgery, and grouped valve position) in a ratio of 5:1 (n = 3,075) with patients receiving conventional management who were randomly selected within the match group. The effectiveness and safety was estimated using major bleeding and thromboembolic events and death as outcomes.

RESULTS

We observed low event rates in the PSM group. After 5 years, PSM was associated with a lower risk of all-cause mortality compared with conventional management (adjusted hazard ratio of 0.49, 95% confidence interval: 0.34 to 0.71). The hazard ratios for thromboembolism and major bleeding were 0.91 (95% confidence interval: 0.66 to 1.24) and 0.83 (95% confidence interval: 0.56 to 1.22).

CONCLUSIONS

Owing to superior clinical effectiveness, self-managed oral anticoagulant therapy may potentially improve the standard of care for patients with mechanical heart valves.