Pulmonary autograft mitral valve replacement: initial experience with the Ross II procedure

BACKGROUND: The renewed interest in mitral valve replacement with a pulmonary autograft encouraged us to perform this procedure in selected patients. METHODS AND RESULTS: From August 2000 to February 2002, 10 patients between 30 and 52 years of age with calcific mitral valvular disease underwent the Ross II procedure. Patients were either in New York Heart Association functional class III (7/10) or IV (3/10). Transthoracic echocardiography was done in all the patients to confirm the diagnosis. A pulmonary autograft was used to replace the diseased mitral valve. Intraoperative transesophageal echocardiography confirmed normal functioning of the autograft. There were 2 early deaths. The 8 survivors are in New York Heart Association functional class I with excellent autograft and homograft function at a follow-up of 2-20 months (mean 9 months). CONCLUSIONS: This procedure is a viable option for mitral valve replacement in patients with calcific mitral valve disease. However, the procedure is technically demanding and requires a valve bank.     

Double freestyle valve replacement in a patient with a prior Ross procedure

Following a Ross procedure, patients may require reintervention for valvular stenosis or insufficiency of either the pulmonary autograft or the pulmonary homograft. Herein is reported a double use of the Medtronic Freestyle stentless bioprosthesis in a patient who previously had undergone a Ross procedure.     

Early postoperative anticoagulation after mechanical valve replacement: a Canadian survey

BACKGROUND AND AIM OF THE STUDY: The optimal approach to anticoagulation during the early postoperative period after mechanical valve replacement, by which early thromboembolism is prevented without bleeding complications, is not yet known. The study aim was to examine the practice patterns of Canadian cardiac surgeons with regard to early postoperative anticoagulation after mechanical valve implantation. METHODS: A questionnaire was sent to 100 Canadian cardiac surgeons in July 2004, and 57 responses were received. Data were collected regarding the approaches to early postoperative anticoagulation following uncomplicated isolated mechanical aortic valve replacement (AVR) and mitral valve replacement (MVR). RESULTS: Heparin was administered routinely after AVR and MVR by 63% and 68% of surgeons, respectively. This was most commonly initiated on postoperative day (POD) 1, and given either subcutaneously (AVR, 28%; MVR, 25%) or intravenously (AVR, 33%; MVR, 42%). Alternatively, low-molecular-weight heparin was used by 21% and 23% of surgeons after AVR and MVR, respectively. Oral warfarin was usually started on POD 1 (72% and 68%, respectively), with 40% prescribing an initial dose between 2.5 and 5.0 mg, and 51% administering between 5.1 and 7.5 mg. When heparin was not used, oral anticoagulation was more often administered earlier (AVR, p = 0.003; MVR, p = 0.006), but not at higher doses (AVR, p = 0.07; MVR, p = 0.2). Following surgery, aspirin was prescribed by 61% and 65% of surgeons after AVR and MVR, respectively. CONCLUSION: The study results highlighted a significant variability in the management of early postoperative anticoagulation after mechanical valve implantation. The clinical impact of these findings is unknown, and can only be assessed through a prospective trial.     

老年患者心脏机械瓣膜置换术后早期华法林抗凝治疗依从性及其影响因素

目的 调查老年患者心脏机械瓣膜置换术(MHVR)后早期华法林抗凝治疗依从性及其影响因素.方法 采用便利抽样法选取2017年1月至2019年10月期间在宁波市医疗中心李惠利医院心胸外科行心脏MHVR的老年患者210例进行前瞻性随访.调查时间为患者出院后6个月后,采用面对面问卷填写或电话随访的方式,调查患者的一般资料、华法...     

Low-dose oral anticoagulation in patients with mechanical heart valve prostheses: final report from the early self-management anticoagulation trial II.

AIMS: In mechanical heart valve recipients, low-dose international normalized ratio (INR) self-management of oral anticoagulants can reduce the risk of developing thrombo-embolic events and improve long-term survival compared with INR control by a general practitioner. Here, we present data on the safety of low-dose INR self-management. METHODS AND RESULTS: In a prospective, randomized multi-centre trial, 1346 patients with a target INR range of 2.5-4.5 and 1327 patients with a target INR range of 1.8-2.8 for aortic valve recipients and an INR range of 2.5-3.5 for mitral or double valve recipients were followed up for 24 months. The incidence of thrombo-embolic events that required hospital admission was 0.37 and 0.19% per patient year in the conventional and low-dose groups, respectively (P = 0.79). No thrombo-embolic events occurred in the subgroups of patients with mitral or double valve replacement. The incidence of bleeding events that required hospital admission was 1.52 and 1.42%, respectively (P = 0.69). In the majority of patients with bleeding events, INR values were < 3.0. Mortality rate did not differ between the study groups. CONCLUSION: Data demonstrate that low-dose INR self-management does not increase the risk of thrombo-embolic events compared with conventional dose INR self-management. Even in patients with low INR target range, the risk of bleeding events is still higher than the risk of thrombo-embolism.     

Aortic valve replacement with pulmonary autograft (the Ross procedure) in adult and pediatric patients

Aortic valve replacement with pulmonary autograft was first performed by Donald Ross in 1967. Initially, the procedure was not widely accepted, by Cardiologists and Cardiac surgeons fundamentally due to its complexity and demanding surgical technique, and because innumerous series two cardiac valves were at risk. The results published in the last 10-15 years established the pulmonary autograft as one of the best methods of aortic valve replacement, especially in pediatric patients and young adults. In the present article, we reviewed present indications and contraindications, and our clinical experience with 26 patients (pediatrics and adults). Analysis of the first 22 the patients with a minimum of 6 months of follow-up (180-620 days) was performed. Follow-up is complete (100%). Mean age was 31.4 +/- 12.6 years. Five patients were pediatrics (<= 14 years). Three patients (11%) with previous percutaneous procedures and 4 patients (14%) with previous surgical procedures. There was no early or late mortality. In the last follow-up, 19 of 22 (86.36%) had no autograft insufficiency (>= grade 1), and in one patient it was moderate (grade 2). The 2 remaining patients developed severe autograft insufficiency (grade 4) and were reoperated on, with satisfactory postoperative outcome. Mean maximal gradient was 7.85 +/- 5 mmHg at 18 months (3-29). Patients with preoperative aortic stenosis showed a significant reduction in myocardial mass index (208.7 +/- 32 a 95.8 +/- 28.8 g/m2) at 18 months. In these patients, septal and posterior wall thickness decreased significantly, in the first month. Two pediatric patients have developed transpulmonar gradient > 50 mmHg. One of them underwent successful stent implantation. We have not observed significant homograft insufficiency in any of our patients. All our patients remain asymptomatic (functional class I) without medical treatment. We have not observed either thromboembolic or haemorrhagic episodes, nor endocarditis. No patient is receiving anticoagulants. Clinical and echocardiographic mid term results in pulmonary autograft and homograft in our series, are excellent after the Ross procedure.     

亚治疗剂量低分子肝素作为机械瓣膜患者再次外科手术的桥接抗凝治疗效果

目的 机械心脏瓣膜（MHV）患者接受再次手术时，需要中断华法林的抗凝治疗，往往需要桥接低分子肝素（LMWH）进行抗凝。本研究的目的是评估MHV患者再次接受择期手术（心脏手术和非心脏手术）桥接亚治疗剂量的LMWH是否是一种安全有效的方法。 方法 观察我院在2013年1月1日到2018年1月1日收治的需再次择期手术的机械瓣膜置换术后患者（瓣膜置换组，n = 47），瓣膜置换组纳入标准是围手术期桥接抗凝的机械瓣置换的患者,并经心外科医生制定桥接抗凝方案患者（机械瓣主动脉瓣置换术后患者14例，机械瓣二尖瓣/双瓣置换术后患者33例），以同期行相同手术的患者（未做过瓣膜置换术）为对照组（n = 47），主要观察指标是住院病死率、术中出血量、桥接后30 d内血栓栓塞事件或主要出血事件的发生率。 结果 瓣膜置换组术中出血量及术后第一个24 h出血量较对照显著增多（P < 0.05），瓣膜置换组1例死亡（2%），死亡原因为低心排，并出现1例（2%）出血事件，两组均未发生栓塞事件，但与对照组相比两组病死率、栓塞事件和出血事件发生率均无显著性差异。 结论 机械瓣膜置换术后患者在进行择期外科手术期间采用亚治疗剂量LMWH进行桥接抗凝术中出血量增多，但严重并发症发生率无显著增加，此结论尚需进一步验证。     

Outcome after aortic valve replacement: comparison of homografts with mechanical prostheses

BACKGROUND AND AIM OF THE STUDY: Aortic valve replacement (AVR) in younger patients is conventionally performed using a mechanical prosthesis (MP), although homograft (HG) implantation is an accepted alternative. This study compares, retrospectively, the follow up of these two dissimilar prostheses. METHODS: Since 1990, a total of 147 Sorin Bicarbon MPs and 285 HGs have been implanted at the authors' institution, and compared statistically for survival, reoperation rate and valve-dependent complications. Only patients aged <70 years were included in the study. RESULTS: The demographic parameters of both patient groups differed with regards to gender, age at the time of implantation, and duration of follow up. Survival was superior in the HG group (log-rank, p = 0.01). Sixteen of 42 late deaths in the MP group were valve-related due to cerebral infarction (n = 7), ventricular arrhythmias (n = 3), or ventricular failure (n = 6). Six of 24 deaths after HG implantation were valve-related (all prosthesis infections). The choice of valve type and patient age were independent risk factors in the multivariate analysis. Freedom from reoperation was superior after MP implantation (log rank, p = 0.007); in six MP patients the indications for redo surgery were prosthesis infection (n = 2) and paravalvular leak (n = 4). In 20 HG patients, redo surgery was required due to prosthesis infection (n = 12), stenotic degeneration (n = 2), regurgitation > grade II (n = 4), or paravalvular leak (n = 2). Age at the time of implantation and valve type were independent risk factors. Thromboembolic complications were mainly seen in MP patients (log rank, p <0.001): there were five ischemic infarctions and 11 transient ischemic attacks (TIAs) compared to three TIAs among HG patients. Cerebral bleeding was found in only 18 cases after MP implantation, and in no cases after HG implantation. In the multivariate analysis, the type of prosthesis was an independent risk factor. CONCLUSION: As expected, these data confirm a longer time period without need for reoperation after MP implantation, but demonstrate a significantly higher survival and fewer complications after AVR with HG.     

Bivalirudin for anticoagulation in mechanical aortic valve replacement and heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a potentially serious syndrome. Since there are some alternatives to treatment with heparin in patients who develop HIT, the decision as to which to use should be based on renal and hepatic function, drug availability and the available monitoring resources. We report a patient who received heparin for mechanical aortic valve replacement. Her clinical course was complicated by HIT, which was treated initially by danaparoid. The syndrome progressed with new thrombotic complications, and eventually was treated successfully by bivalirudin (Angiomax; Medison Pharma Ltd, Petach Tikva, Israel) for 9 days. We propose that treatment with bivalirudin for several days is a safe and effective alternative to heparin therapy in patients who develop HIT.     

Drug insight: an overview of current anticoagulation therapy after heart valve replacement

Vitamin K antagonists, such as warfarin, are the gold standard approach for the long-term anticoagulant therapy of patients with mechanical heart valves. Management decisions are, however, based predominantly on expert consensus and on data from nonrandomized, follow-up studies, which have inherent limitations in their methods. Low-intensity anticoagulation therapy provides protection against thromboembolic complications in patients with most types of modern prosthetic heart valve. The addition of low-dose aspirin is safe if international normalized ratio values below 3.5 are maintained. A combined regimen should be considered in high-risk patients and those with coexistent coronary artery or cerebrovascular disease, and in patients who have suffered a thromboembolic event despite a therapeutic international normalized ratio. Thromboprophylaxis with unfractionated or low-molecular-weight heparins is restricted to specific situations, such as when a patient is intolerant to vitamin K antagonists, when surgical procedures require discontinuation of oral anticoagulation, or when the patient is pregnant. A lack of uniformity across practice guidelines make it difficult to reach treatment decisions. Each patient's preference, expressed after counseling about the risks and benefits of each treatment strategy, and an individual assessment of the patient's risk factors, should guide treatment decisions. At present, new anticoagulant agents such as factor Xa inhibitors do not represent a treatment option for heart valve recipients.     

心脏瓣膜置换并射频消融术后华法林抗凝治疗的方法探讨

目的探讨心脏瓣膜置换并直视射频消融术后华法林的抗凝治疗方法。方法将130例心脏瓣膜病合并房颤患者分为2组,A组(60例)行瓣膜置换并射频消融术治疗,术后服用胺碘酮治疗6个月,同时服用华法林抗凝治疗;B组(70例)单纯行瓣膜置换术治疗,术后仅服用华法林抗凝治疗。结果术后随访3～16个月,A、B组死亡各1例,均为非抗凝相关死亡。A组出现抗凝所致轻度出血5例、血栓栓塞0例,INR异常升高4例;B组分别为3、3、1例。两组比较,P均>0.05。达抗凝稳态时,两组不同术式患者华法林剂量比较,P均>0.05。达到抗凝稳态时,A组华法林剂量为(2.43±0.58)mg/d,INR为1.83±0.55。结论瓣膜置换同期直视射频消融术后患者应加强抗凝监测,根据INR适度减少华法林用量,避免发生出血。     

机械瓣膜置换术后的随访研究

目的：总结心脏瓣膜病机械瓣膜置换术后疗效,旨在评价心脏瓣膜置换手术的效果及手术后的中长期效果。方法选择本院2000年-2012年我院确诊的心脏瓣膜病患者300例,观察本组患者心脏瓣膜病机械瓣膜置换术后的临床疗效,术后并发症的原因以及发病例数。结果患者的手术之后心功能随访显示,患者心功能与血液动力学出现了很大的改善,并且,大部分患者的劳动能力得到了很大的改善,生活的质量出现了明显的提高。结论我院心脏瓣膜病机械瓣膜置换手术预后整体效果较好,手术的死亡率是可以接受的,和国内的比较并无明显的差别,大部分的患者在手术之后的心功能和生活的质量得到了明显的改善。