Are all bileaflet mechanical valves equal?

Challenges and Priorities for Children With Congenital Valvar Heart Disease: The Heart Valve Collaboratory

The Heart Valve Collaboratory is a multidisciplinary, patient-centered community of stakeholders addressing complex problems and embracing innovation to help patients with heart valve disease achieve their fullest potential for health. The Scientific Council is composed of cardiologists, surgeons, ex-officio representatives of the Food and Drug Administration and Centers for Medicare and Medicaid Services, National Heart Lung Blood Institute, and representatives from industry partners. In October 2022, this group convened a workshop that included experts from stakeholder groups to address the unmet and clinical needs of patients with pediatric and congenital heart valve disease. The following document includes the discussion and summary of the current state of valve therapy and the needs being addressed for valve development.

Guidelines for the Evaluation of Prosthetic Valve Function With Cardiovascular Imaging: A Report From the American Society of Echocardiography Developed in Collaboration With the Society for Cardiovascular Magnetic Resonance and the Society of Cardiovascular Computed Tomography

In patients with significant cardiac valvular disease, intervention with either valve repair or valve replacement may be inevitable. Although valve repair is frequently performed, especially for mitral and tricuspid regurgitation, valve replacement remains common, particularly in adults. Diagnostic methods are often needed to assess the function of the prosthesis. Echocardiography is the first-line method for noninvasive evaluation of prosthetic valve function. The transthoracic approach is complemented with two-dimensional and three-dimensional transesophageal echocardiography for further refinement of valve morphology and function when needed. More recently, advances in computed tomography and cardiac magnetic resonance have enhanced their roles in evaluating valvular heart disease. This document offers a review of the echocardiographic techniques used and provides recommendations and general guidelines for evaluation of prosthetic valve function on the basis of the scientific literature and consensus of a panel of experts. This guideline discusses the role of advanced imaging with transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance in evaluating prosthetic valve structure, function, and regurgitation. It replaces the 2009 American Society of Echocardiography guideline on prosthetic valves and complements the 2019 guideline on the evaluation of valvular regurgitation after percutaneous valve repair or replacement.

Aortic Valve Insufficiency in the Teenager and Young Adult

The contents of this article were presented in the session “Aortic insufficiency in the teenager” at the congenital parallel symposium of the 2013 Society of Thoracic Surgeons (STS) annual meeting. The accompanying articles detail the approaches of aortic valve repair and the Ross procedure.1,2 The current article focuses on prosthetic valve replacement. For many young patients requiring aortic valve surgery, either aortic valve repair or a Ross procedure provides a good option. The advantages include avoidance of anticoagulation and potential for growth. In other patients, a prosthetic valve is an appropriate alternative. This article discusses the current state of knowledge regarding mechanical and bioprosthetic valve prostheses and their specific advantages relative to valve repair or a Ross procedure. In current practice, young patients requiring aortic valve surgery frequently undergo valve replacement with a prosthetic valve. In STS adult cardiac database, among patients ≤30 years of age undergoing aortic valve surgery, 34% had placement of a mechanical valve, 51% had placement of a bioprosthetic valve, 9% had aortic valve repair, and 2% had a Ross procedure. In the STS congenital database, among patients 12 to 30 years of age undergoing aortic valve surgery, 21% had placement of a mechanical valve, 18% had placement of a bioprosthetic valve, 30% had aortic valve repair, and 24% had a Ross procedure. In the future, the balance among these options may be altered by design improvements in prosthetic valves, alternatives to warfarin, the development of new patch materials for valve repair, and techniques to avoid Ross autograft failure.

The Intervened Heart: Cardiac Hardware in the Forensic Suite

Cardiovascular interventions—in the form of bypass grafts, stents, prosthetic valves, and ventricular assist devices—are increasingly common for the typical citizen of the industrialized world. While these certainly contribute to longevity and improved quality of life, they can also be a source of morbidity and mortality. In most cases, a handful of predictable pathogenic pathways underlie the eventual degeneration or failure of the various interventions, and may be implicated as a cause of death. Much less frequently, an untoward and unexpected complication can be the culprit. The objectives of this manuscript are to describe the more common cardiac interventions (both mechanical and surgical), highlight the typical failure modes, and present approaches to evaluate devices and grafts when encountered in the forensic autopsy suite.

LOWERing the INtensity of oral anticoaGulant Therapy in patients with bileaflet mechanical aortic valve replacement: results from the "LOWERING-IT" Trial

BACKGROUND

Moderate anticoagulation after mechanical heart valve replacement has been proposed to reduce the risk of bleeding related to lifelong anticoagulation. However, the efficacy of such reduced antithrombotic regimens is still unknown. The present prospective open-label, single-center, randomized controlled trial aimed to evaluate the safety and feasibility of reduced oral anticoagulation after isolated mechanical aortic valve replacement.

METHODS

Low-risk patients undergoing bileaflet mechanical aortic valve replacement were randomized to a low International normalized ratio (INR) target (1.5-2.5; LOW-INR group) or to the standard currently recommended INR (2.0-3.0; CONVENTIONAL-INR group) through daily coumarine oral therapy. No aspirin was added. Median follow-up was 5.6 years. The primary outcome was assessment of noninferiority of the low over the standard anticoagulation regimen on thromboembolic events. Secondary end point was the superiority of the reduced INR target strategy on bleeding events.

RESULTS

We analyzed 396 patients (197 in the LOW-INR group and 199 in the CONVENTIONAL-INR group). The mean of INR was 1.94 +/- 0.21 and 2.61 +/- 0.25 in the LOW-INR and CONVENTIONAL-INR groups, respectively (P < .001). One versus three thromboembolic events occurred in the LOW-INR and CONVENTIONAL-INR, respectively, meeting the noninferiority criterion (P = .62). Total hemorrhagic events occurred in 6 patients in the LOW-INR group and in 16 patients in the CONVENTIONAL-INR group (P = .04).

CONCLUSIONS

LOWERING-IT trial established that the proposed LOW-INR target is safe and feasible in low-risk patients after bileaflet aortic mechanical valve replacement. It results in similar thrombotic events and in a significant reduction of bleeding occurrence when compared to the conventional anticoagulation regimen.