Phenprocoumon based anticoagulation is an underestimated factor in the pathogenesis of calciphylaxis

Sailing between scylla and charybdis-anticoagulation dilemma in a patient with calciphylaxis and mechanical cardiac valve replacement: a case report and literature review

Calciphylaxis is a rare and life-threatening condition in patients with end-stage kidney disease (ESKD). In this case report, we reported a 72-year-old female who had undergone aortic and mitral mechanical valve replacement 22 years ago due to rheumatic aortic and mitral stenosis. Following the valve replacement, she initiated warfarin treatment. Five years ago, she received a diagnosis of uremia and has since been undergoing regular hemodialysis. Ten months prior to her current admission, she experienced excruciating pain and was diagnosed with calciphylaxis. Additionally, an electrocardiogram revealed atrial fibrillation, while echocardiography indicated that the aortic and mitral mechanical valves were appropriately positioned, with normal perivalvular surroundings and good valve leaflet activity. No noticeable thrombosis was observed in the left atrium or left atrial appendage. Color Doppler imaging showed moderate stenosis in the lower extremity arteries, with no venous thromboembolism present. Extensive eggshell-like calcification within the arterial media was detected. The patient was managed with regular hemodialysis, symptomatic treatments (including anticoagulation and analgesia), and sodium thiosulfate. Unfortunately, symptomatic management provided limited relief, and during the one-month follow-up period, the patient passed away due to septic shock. Currently, there is insufficient conclusive evidence regarding alternative influential anticoagulants or appropriate prosthetic valve selection. For individuals with ESKD receiving maintenance hemodialysis, early identification, diagnosis, and treatment of calciphylaxis are of paramount importance.

Calciphylaxis and its co-occurrence with connective tissue diseases

Calciphylaxis, also known as calcific uremic arteriopathy, is a rare calcification syndrome that presents as ischemic skin necrosis and severe pain. It has a high mortality rate and is characterised by calcification of the small and medium arteries and micro-thrombosis. Calciphylaxis mainly occurs in patients with end-stage renal disease. In recent years, there have been an increasing number of cases of calciphylaxis associated with connective tissue diseases. Given the absence of clear diagnostic criteria for calciphylaxis thus far, an early diagnosis is crucial for designing an effective multidisciplinary treatment plan. In this article, we review the research progress on calciphylaxis and describe its characteristics in the context of connective tissue diseases.

A Scoping Review of Alternative Anticoagulation Strategies for Hemodialysis Patients with a Mechanical Heart Valve

INTRODUCTION

Patients with end-stage renal disease (ESRD) have high rates of cardiac valvulopathy but can develop contraindications for vitamin K antagonist (VKA) therapy. We explored the evidence for alternative anticoagulation strategies in patients with ESRD with a contraindication for VKA therapy.

METHODS

A scoping review was completed, searching MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Conference abstracts from inception to March 30, 2021. The study population was patients with ESRD who were on VKA therapy and developed a contraindication to VKA therapy use. All data regarding studies, patient characteristics, anticoagulation strategy, and clinical outcomes were summarized.

RESULTS

Twenty-three articles met inclusion criteria. These articles included 57 patients. Contraindications to VKA therapy included calcific uremic arteriolopathy (CUA) (n = 55) and warfarin-induced skin necrosis (n = 2). All studies were either case reports or case series. There were 10 anticoagulation strategies identified. Continuation of VKA therapy was associated with increased death and decreased rates of CUA resolution (80.0% and 10.0%, respectively), compared to apixaban (24.0% and 70.8%), subcutaneous (SC) low-molecular-weight heparin (LMWH) (14.3%, 85.7%), and SC unfractionated heparin (0.0%, 100.0%). While only 5 patient cases were reported with mechanical heart valves, SC LMWH use has been reported in this context with good outcomes.

CONCLUSIONS

In patients with ESRD who develop a contraindication to VKA therapy, several alternative anticoagulation strategies have been reported with superior outcomes to VKA continuation. While outcomes appear superior to continuation of VKA therapy, more data are required before definitive recommendations can be made for the patient with ESRD and a mechanical heart valve.