Leaflet thrombosis in transcatheter aortic valve intervention: mechanisms, prevention, and treatment options

IntroductionTranscatheter aortic valve intervention (TAVR) has emerged as a promising alternative to surgical aortic valve replacement for patients with severe aortic stenosis. However, leaflet thrombosis has raised concerns about the long-term durability and outcomes of TAVR. This study aims to provide an overview of the mechanisms, prevention strategies, and treatment options for leaflet thrombosis in TAVR.Clinical evidenceLeaflet thrombosis refers to the formation of blood clots on bioprosthetic valve leaflets, leading to impaired leaflet mobility, early valve degeneration and dysfunction, and potential clinical implications. While the mechanisms underlying thrombus formation on valve leaflets are not fully understood, several factors, such as altered blood flow patterns within valve neosinuses, prothrombotic surfaces, and patient-related causes, have been implicated. Two distinct entities have been identified, namely, hypoattenuated leaflet thickening and restricted leaflet motion. Their occurrence appears dynamic over time and is related to the valve type. Imaging, including transesophageal echocardiography and multidetector computed tomography, plays a crucial role in the diagnosis and follow-up of leaflet thrombosis.Prevention and treatment optionsPreventing leaflet thrombosis requires a comprehensive and tailored approach involving identifying high-risk patients, close monitoring, and antithrombotic therapy. Antithrombotic therapy with dual antiplatelet agents or anticoagulation is commonly employed in TAVR patients, although the optimal regimen is yet to be defined. Novel antithrombotic agents, such as direct oral anticoagulants, are being investigated for their efficacy and safety in preventing leaflet thrombosis. When leaflet thrombosis is detected, treatment options include intensified antithrombotic therapy, valve-in-valve intervention, or balloon valvuloplasty. The long-term outcomes and impact of leaflet thrombosis on valve durability and patient prognosis are areas of ongoing research.SummaryLeaflet thrombosis in TAVR is a considerable complication affecting valve function and patient outcomes. Understanding the mechanisms underlying thrombus formation and implementing appropriate prevention strategies are essential for mitigating this risk. Treatment options aim to restore leaflet mobility and optimize valve performance. Further research is needed to establish standardized protocols for antithrombotic therapy, identify high-risk patient populations, and determine the long-term consequences of leaflet thrombosis on TAVR outcomes

Myocardial Infarction Across COVID‐19 Pandemic Phases: Insights From the Veterans Health Affairs System

Background Cardiovascular procedural treatments were deferred at scale during the COVID‐19 pandemic, with unclear impact on patients presenting with non–ST‐segment–elevation myocardial infarction (NSTEMI). Methods and Results In a retrospective cohort study of all patients diagnosed with NSTEMI in the US Veterans Affairs Healthcare System from January 1, 2019 to October 30, 2022 (n=67 125), procedural treatments and outcomes were compared between the prepandemic period and 6 unique pandemic phases: (1) acute phase, (2) community spread, (3) first peak, (4) post vaccine, (5) second peak, and (6) recovery. Multivariable regression analysis was performed to assess the association between pandemic phases and 30‐day mortality. NSTEMI volumes dropped significantly with the pandemic onset (62.7% of prepandemic peak) and did not revert to prepandemic levels in subsequent phases, even after vaccine availability. Percutaneous coronary intervention and coronary artery bypass grafting volumes declined proportionally. Compared with the prepandemic period, patients with NSTEMI experienced higher 30‐day mortality during Phases 2 and 3, even after adjustment for COVID‐19‐positive status, demographics, baseline comorbidities, and receipt of procedural treatment (adjusted odds ratio for Phases 2 and 3 combined, 1.26 [95% CI, 1.13–1.43], P<0.01). Patients receiving Veterans Affairs‐paid community care had a higher adjusted risk of 30‐day mortality compared with those at Veterans Affairs hospitals across all 6 pandemic phases. Conclusions Higher mortality after NSTEMI occurred during the initial spread and first peak of the pandemic but resolved before the second, higher peak—suggesting effective adaptation of care delivery but a costly delay to implementation. Investigation into the vulnerabilities of the early pandemic spread are vital to informing future resource‐constrained practices

Parental attitudes toward fertility preservation in boys with cancer: context of different risk levels of infertility and success rates of fertility restoration

To measure the parental attitudes toward fertility preservation in boys with cancer. Retrospective cohort study. Questionnaire survey via regular mail. A total of 465 families whose sons were already treated for cancer. The questionnaire was designed for two groups based on child's age at the time of cancer diagnosis: <12 and ≥12 years old. Descriptive statistics regarding a positive or negative attitude of parents toward fertility preservation options in the context of different risk levels of infertility and success rates of fertility restoration. The response rate was 78%. Sixty-four percent of parents of boys ≥12 years old would agree to store sperm obtained by masturbation and/or electroejaculation, and 54% of parents of boys <12 years old would agree to store a testicular biopsy. If the risk of infertility or the success rate of fertility restoration were ≤20%, more than one-fourth of parents would still opt for fertility preservation. All parents should be counseled about the risks of infertility due to cancer treatment, because many parents want to preserve their son's fertility even if the risk of becoming infertile or the chances on fertility restoration are lo