Longest Event-Free Survival without Anticoagulation in a Mechanical Aortic Valve Replacement

Abstract

A male patient in his early 90s with a past medical history of hypertension and dyslipidemia and a surgical history of prosthetic (mechanical) aortic valve replacement (AVR) performed 27 years ago (1988) for aortic stenosis presented to our hospital with a chief medical complaint of fatigue, weakness, and chills for a duration of one day. His medications at home included clopidogrel, chlorthalidone, valsartan, and metoprolol. He had discontinued taking warfarin a few weeks after being discharged from his valve replacement surgery because of excessive bruising. His primary care doctor later started him on clopidogrel in 2001.His initial vitals in the emergency department were stable, except for a low-grade temperature of 100.4 °F. The physical examination revealed dry mucous membranes and a grade 3/6 systolic murmur, and metallic aortic valve opening and closing clicks at the aortic area along with a grade 2/6 systolic murmur at the apex. His electrocardiography revealed a normal sinus rhythm with signs of chamber enlargements. Chest X-ray revealed enlarged cardiac silhouette and the presence of heart valve prosthesis. Initial blood tests included total biochemistry, complete blood count, prothrombin time, partial thromboplastin time, fibrinogen, and thyroid function tests. All were unremarkable, except for creatinine of 2.30 and BUN of 51. A functional aortic prosthetic (metallic) valve with a maximum/mean gradient of 72/39 mmHg was verified with transthoracic echocardiography. In addition, a mildly elevated pulmonary artery pressure of 40 mmHg and a left ventricular ejection fraction of 55-65% were estimated; there was no evidence of thrombus or pannus formation.The patient was admitted with a diagnosis of acute kidney injury secondary to dehydration, and he was successfully treated with intravenous (IV) hydration. After educating the patient about the consequences of thrombosis and thromboembolism (TE) in patients with metallic heart valves, he was immediately bridged with IV heparin onto oral warfarin, with which he was discharged on. His international normalized ratio (INR) at discharge was in the therapeutic range at 2.6. Case 2The second case is a male patient in his 60s with a past medical history of chronic hepatitis C and rheumatic aortic valve disease and a surgical history of prosthetic AVR performed 37 years ago for aortic valve incompetence. He underwent AVR with Braunwald-Cutter prosthesis at 22 years of age. The aortic valve was replaced again five years later with a Björk-Shiley (B-S) valve due to fractures of the valve's outlet AbstrACt: Sixty percent of the patients going for valve replacement opt for mechanical valves and the remaining 40% choose bioprosthetics. Mechanical valves are known to have a higher risk of thrombosis; this risk further varies depending on the type of valve, its position, and certain individual factors. According to current guidelines, long-term anticoagulation is indicated in patients with metallic prosthetic valve disease. We report two unique cases of patients who s...

Short‐term evaluation of thromboresistance of a poly(ether ether ketone) (PEEK) mechanical heart valve with poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC)‐grafted surface in a porcine aortic valve replacement model

“…It was attributed to “good luck” that some patients with mechanical AVR spent event‐free life without anticoagulation . Thus, anticoagulants such as warfarin are inevitable for almost all patients with mechanical valves.…”

“…It was attributed to "good luck" that some patients with mechanical AVR spent event-free life without anticoagulation. 22 Thus, anticoagulants such as warfarin are inevitable for almost all patients with mechanical valves. Reducing warfarin dosage is important to decrease adverse event risks such as hemorrhage, and the development of a mechanical valve that enables the reduction of warfarin dosage is of significance.…”

New warfarin anticoagulation management model after heart valve surgery: rationale and design of a prospective, multicentre, randomised trial to compare an internet-based warfarin anticoagulation management model with the traditional warfarin management model

“…After mechanical heart valve replacement surgery, patients must undergo warfarin anticoagulation therapy for a long period of time 15 16. In the traditional anticoagulation management model, patients must visit large tertiary hospitals for blood analysis.…”

A 31-year-old patient without the use of warfarin and with an aortic mechanical valve

“…They have also reported on the longest survey of 37 years (3). Aman (4) has reported another case that has survived for 33 years without anticoagulation.…”

“…In the literature, there are some cases without anticoagulation for over 30 years without significant embolic events; such cases have been reviewed in the study by Salmane et al ( 3 ). They have also reported on the longest survey of 37 years ( 3 ). Aman ( 4 ) has reported another case that has survived for 33 years without anticoagulation.…”