Mechanical Heart Valve Patients Research Articles

Abstract 12810: Short-Term Hospital Outcomes of Elderly Patients With Mechanical vs. Bioprosthetic Heart Valves Admitted for NSTEMI

Introduction: Valvular heart disease(VHD) is a significant cause of morbidity and mortality among the elderly. While the use, merits, and demerits of mechanical heart valves (MHV) and bioprosthetic heart valves(BHV) to treat VHD are well-documented in the literature, there needs to be more data on the outcomes following events of NSTEMI. Methods: We explored the 2016-2020 National Inpatient Sample for patients ages≥60 years hospitalized for a primary diagnosis of NSTEMI via their ICD-10 codes. We further retained those with a presence of MHV or BHV, and differences in outcomes between the two groups were evaluated. Results: Our study found 32775 adults of age 60 and more hospitalized with NSTEMI, which included 23670 (72.2%) cases with MHV, while 9105 (27.8%) patients had a BHV. No differences in mean Charlson Comorbidity Index (CCI) scores were found between the two groups (mean CCI in MHV patients: 4.14 vs. 4.22 in those with BHV, p=0.233). Compared to cases with BHV, those with MHV showed higher odds of acute kidney injury (aOR 1.108, p<0.01), atrial fibrillation (aOR 1.110, p<0.01), supraventricular tachycardia (aOR 1.46, p<0.01), and use of CABG (aOR 1.289, p=0.031). However, patients with MHV were less likely to undergo PCI for NSTEMI than those with BHV (aOR 0.781, p<0.01). No differences between the two cohorts were found for events of ventricular tachycardia (aOR 0.907, p=0.072), ventricular fibrillation (aOR 1.021, p=0.80), cardiogenic shock (aOR 1.012, p=0.876), or death (aOR 0.928, p=0.187). Finally, those with MHV reported a slightly more extended stay (mean length of stay 4.41 days) than those with BHV (mean length of stay 4.02 days, p<0.01). Conclusions: Patients with MHV showed higher odds of complications such as AKI, Atrial fibrillation, supraventricular tachycardia, and use of CABG following NSTEMI while reporting lower odds of PCI use than those with BHV.

Association of sex with major bleeding risks in sub-Saharian anticoagulated patients with mechanical heart valves: A cohort study from the Khartoum Emergency Salam Centre.

BackgroundRheumatic heart disease (RHD) with mechanical heart valve (MHV) replacement is common in Africa. However, MHV requires lifelong anticoagulation that could have a particular impact in women in reproductive age. MethodsWe report data of a prospective observational cohort study conducted between August 2018 and September 2019 in MHV patients in the Salam Centre for Cardiac Surgery built in Khartoum by Emergency, an Italian Non-Governmental Organization, to evaluate bleeding risk, its associated determinants, and the impact of lifelong anticoagulation in fertile women. ResultsWe studied 3647 patients (median age 25.1 years; 53.9% female). During follow-up [median time 1.1 (0.1–1.2) years], we recorded 85 major bleedings (rate 2.16 × 100 pt-years), Major bleedings occurred more frequently among women (64/85 cases, 75.3%; rate 3.0 × 100 pt-years), compared to men (21/85 cases, 24.7%; rate 1.16 × 100 pt-years) (RR 2.6; 95% CI 1.6–4.5; p = 0.0001). Multivariate analysis was performed to identify variables associated with major bleeding, and female sex was the only risk factor significantly associated, whereas aspirin treatment and higher INR target showed a non-significant trend for higher bleeding risk. Thirty-two/85 (37.6%) of major bleedings were metrorrhagias. When we calculate the incidence of major bleedings after the exclusion of gynecological events, no sex differences in the bleeding risk were found (HR 1.3, 95% CI 0.8–2.3; p = 0.3). ConclusionsBleeding risk of young MHV patients on oral anticoagulant therapy is higher among women, mainly due to metrorrhagia. Women in the reproductive life are at high risk for gynecological bleeding when treated with anticoagulants.

Abstract TMP83: Optimal Timing For Resumption Of Anticoagulation After Intracranial Hemorrhage In Patients With Mechanical Heartvalves

Introduction: Anticoagulation in patients with acute intracranial hemorrhage (ICH) and mechanical heart valves (MHV) is often held to mitigate the risk of ICH expansion or recurrence; however there exists a competing risk of acute ischemic stroke (AIS). Optimal timing to resume anticoagulation after ICH remains uncertain. Methods: We retrospectively studied ICH patients with MHV at two academic hospitals from April, 2000-August, 2018. The primary outcome was a composite endpoint of symptomatic hematoma expansion or new ICH, AIS, and intracardiac thrombus up to 30 days post-ICH. The exposure was timing of re-initiation of anticoagulation classified as early if therapeutic anticoagulation was resumed up to 7 days after ICH; late if ≥7 and up to 30 days after ICH; and never if not resumed or resumed after 30-days post-ICH. Cox proportional hazard models were built adjusted for age, sex, and covariates significantly different in univariate analysis at a pre-specified p-value threshold of 0.05. Results: We identified 184 patients with ICH and MHV (65 anticoagulated early, 100 resumed late, 19 not resumed by day 30 post-ICH). We observed 12 AIS, 16 new ICH, and 6 intracardiac thromboses. The mean time from ICH to anticoagulation in the cohort was 12.7 days. Patients resumed early versus late were more likely to have atrial fibrillation (62% versus 42%), and less likely to be reversed (75% versus 94%), to undergo hematoma evacuation (23% versus 43%), have midline shift (27% versus 52.9%), and to have intracerebral involvement (26% versus 49%). There was no significant difference in the hazard of AIS, new or symptomatic ICH expansion, or the composite outcome among those resumed early versus late. Patients not resumed within 30 days post-ICH had a significantly higher risk of AIS compared to those resumed within 30 days (HR 15.9; 95% C.I.1.9-129.7, p=0.0098). Discussion: In this study of ICH patients with MHV, there was no difference in the 30-day thrombotic and hemorrhagic brain-related outcomes in patients anticoagulated within 7 days versus 7-30 days. Withholding anticoagulation within the first 30 days was associated with a significantly higher risk of AIS. Our findings provide a discrete time window to guide resumption of anticoagulation in MHV patients with ICH.

Development and validation of a bleeding risk prediction score for patients with mitral valve stenosis and atrial fibrillation or mechanical heart valves receiving long-term warfarin therapy.

This study aimed to develop and validate a new bleeding risk score to predict warfarin-associated major bleeding for patients with mitral valve stenosis with atrial fibrillation (MSAF) or mechanical heart valves (MHV). A multicentre, retrospective cohort study was conducted at 3 hospitals in Thailand. Adult patients with MSAF or MHV receiving warfarin for ≥3months during 2011-2015 were identified. Data collection and case validation were performed electronically and manually. Potential variables were screened using the least absolute shrinkage and selection operator. Multivariate logistic regression analysis using stepwise backward selection was used to construct a risk score. Predictive discrimination of the score was evaluated using the C-statistic. Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test. There were 1287 patients (3903.41 patient-year of follow-up), with 192 experiencing bleeding (4.92 event/100 patient-year) in the derivation cohort. A new bleeding risk score termed, the HEARTS-60 +3 score (hypertension/history of bleeding; external factors, e.g., alcohol/drugs [aspirin or nonsteroidal anti-inflammatory drugs]; anaemia/hypoalbuminaemia; renal/hepatic insufficiency; time in therapeutic range of <60%; stroke; age ≥60 y; target international normalized ratio of 3.0 [2.5-3.5]), was developed and showed good predictive performance (C-statistic [95% confidence interval] of 0.88 [0.85-0.91]). In the external validation cohort of 832 patients (2018.45 patient-year with a bleeding rate of 4.31 event/100 patient-year), the HEARTS-60 +3 score showed a good predictive performance with a C-statistic (95% confidence interval) of 0.84 (0.81-0.89). The HEARTS-60 +3 score shows a potential as a bleeding risk prediction score in MSAF or MHV patients.

Oral anticoagulant management of patients with mechanical heart valves at the Salam Centre of Khartoum: Observations on quality of anticoagulation and thrombotic risk

IntroductionRheumatic heart disease with mechanical heart valve (MHV) replacement is common in Africa. However, MHV requires long-life anticoagulation and managing this can be challenging. Methods and resultsWe report data of a prospective observational study conducted between August 2018 and September 2019 in MHV patients in the Salam Centre for Cardiac Surgery built in Khartoum, by Emergency, an Italian Non-Governmental Organization, to evaluate the quality of anticoagulation control and the risk of thrombotic complications. ResultsWe studied 3647 patients (median age 25.1 years; 53.9 % female). Median Time in Therapeutic Range (TTR) was 53 % (interquartile range 37 % to 67 %) and 70 thrombotic events (rate 1.8 × 100 pt-years [95 % CI 1.38–2.23]) were recorded. Among patients in the first quartile of TTR (≤37 %), we recorded 34/70 (48.6 %) of all thrombotic events (rate 3.7 × 100 pt-years [95 % CI 2.5–5.1]), with a high mortality rate (2.2 × 100 pt-years [95 % CI 1.3–3.3]). In patients with guideline-recommended TTR (≥65 %) the event rate was 0.8 × 100 pt-years for thrombotic events [95 % CI 0.3–1.5] and 0.4 × 100 pt-years for mortality [95 % CI 0.1–0.9].Multivariable analysis showed that having a TTR in the lowest quartile (≤37 %) and being noncompliant are significantly associated with increased thrombotic risk. Aspirin use or different valve type did not influence the thrombotic risk. Almost 40 % of all thromboembolic complications could have been potentially prevented by further improving VKA management to obtain a TTR > 37 %. ConclusionThe thrombotic risk of MHV patients on VKAs living in a low-income country like Sudan is associated with low quality of anticoagulation control. Efforts should be made to decrease the number of non-compliant patients and to reach a guideline-recommended TTR of ≥65 %.

Safety of Vitamin K in mechanical heart valve patients with supratherapeutic INR: A systematic review and meta-analysis.

Patients who had mechanical heart valves and an international normalized ratio (INR) of >5.0 should be managed by temporary cessation of vitamin K antagonist. This study aimed to investigate the safety of low-dose vitamin K1 in patients with mechanical heart valves who have supratherapeutic INR. CINAHL, Cochran Library, Clinical trial.gov, OpenGrey, PubMed, ScienceDirect, and Scopus were systematically searched from the inception up to October 2021 without language restriction. Studies comparing the safety of low-dose vitamin K1 treatment in patients with placebo or other anticoagulant reversal agents were included. We used a random-effect model for the meta-analysis. Publication bias was determined by a funnel plot with subsequent Begg's test and Egger's test. From 7529 retrieved studies, 3 randomized control trials were included in the meta-analysis. Pooled data demonstrated that low-dose vitamin K was not associated with thromboembolism rate (risk ratio [RR] = 0.94; 95% CI: 0.19-4.55) major bleeding rate (RR = 0.58; 95% CI: 0.07-4.82), and minor bleeding rate (RR = 0.60; 95% CI: 0.07-5.09). Subgroup and sensitivity analysis demonstrated the nonsignificant effect of low-dose vitamin K on the risk of thromboembolism. Publication bias was not apparent, according to Begg's test and Egger's test (P = .090 and 0.134, respectively). The current evidence does not support the role of low-dose vitamin K as a trigger of thromboembolism in supratherapeutic INR patients with mechanical heart valves. Nevertheless, more well-designed studies with larger sample sizes are required to justify this research question.

Major bleedings in mechanical prosthetic heart valves patients on Vitamin K antagonist treatment. Data from the PLECTRUM Study

Patients with mechanical prosthetic heart valves (MHV) need vitamin K antagonist (VKA) treatment, due to the high thrombotic risk. The need to evaluate the bleeding risk of these patients is of great clinical relevance. This is an observational retrospective multicenter study among Centers affiliated to the Italian Federation of Anticoagulation Clinics on MHV patients, with the aim to evaluate the risk of major bleeding (MB) and associated risk factors. 2357 patients with MHV were included in the study, patients were followed for 24.081 pt-years; 246 patients had MB (rate 1.0 ×100 pt-yrs), 54 were intracranial hemorrhage (rate 0.22 ×100 pt-yrs). Patients with MB were significantly older, more affected by peripheral obstructive arterial disease (POAD) and atrial fibrillation (AF), and presented a history of previous MB, with respect to patients who did not bleed. Patients with MB showed a trend for lower time in therapeutic range (TTR), and a significant number of patients had a TTR in the lower quartile. Patients with MB had a higher mortality rate with respect to patients who did not bleed (p=0.001). The history of previous bleeding, the presence of POAD or of AF, and a TTR in the lowest quartile, were significantly associated with MB. MHV patients treated with VKAs followed by Anticoagulation Clinics, showed a low bleeding risk. Risk factors associated with major bleeding are older age, the presence of POAD or AF, the history of previous bleeding, and poor quality of anticoagulation. Patients who experienced MB during anticoagulation are at high risk of death.

Outcomes of leadless pacemaker implantation in patients with mechanical heart valves.

Device infections constitute a major complication of transvenous pacemakers. Mechanical heart valves (MHV) increase the risk of infective endocarditis (IE) and pacemaker infection, requiring lifelong vitamin K-antagonists (VKA), which may affect patient management. Leadless pacemakers (LP) are associated with low infection rates, posing an attractive option in MHV patients requiring permanent pacing. This study describes outcomes following LP implantation in patients with MHV. This is a multicenter, observational, retrospective study including consecutive patients implanted with an LP at 5 centers between June 2015 and January 2020. Procedural outcomes, antithrombotic management, complications, performance during follow-up and episodes of bacteremia and IE were compared between patients with and without an MHV (MHV and non-MHV groups). Four hundred fifty-nine patients were included (74 in the MHV group, 16.1%, and 385 in the non-MHV group, 83.9%). Procedural outcomes and acute electrical performance were comparable between groups. Vascular complications and cardiac perforation occurred in 2.7 versus 2.3% (p = 1) and 0% versus 0.8% (p = 1) in the MHV group and non-MHV group. One case of IE occurred in the MHV group and 2 in the non-MHV group. In MHV patients, uninterrupted VKA was used in 83.8%, whereas 16.2% were heparin-bridged. Vascular complication or tamponade occurred in 1 (8.3%) MHV heparin-bridged patient versus 1 (1.6%) MHV uninterrupted VKA patient (p = .3). LP implantation outcomes in MHV patients are comparable to the general LP population. Device-related infections are rare following LP implantation, including in patients with MHV. In the MHV group, periprocedural anticoagulation management was not associated with significantly different rates of tamponade or vascular complication.

Abstract WP168: Anticoagulation Therapy In Endovascular Thrombectomy Patients With Large Vessel Occlusion Due To Cardioembolism

Introduction: In ischemic stroke patients, cardioembolism, predominantly due to atrial fibrillation (AF), is a leading preventable cause of large vessel occlusion (LVO). Despite proven efficacy, inadequate oral anticoagulant (OAC) therapy continues to be a major problem in patients with AF, mechanical heart valves and other potential sources of emboli. Aim: To determine rates of cardioembolic LVO, the adequacy of OAC, and the association of OACs with clinical outcomes in LVO patients treated with endovascular thrombectomy (EVT). Methods: Trial of Org 10172 in Acute Stroke Treatment classification was used to determine stroke etiology in consecutive patients treated with EVT. Pre-stroke indication for OAC and the adequacy of anticoagulation were determined for patients with cardioembolic LVO. The primary outcome was 3-month functional independence (modified Rankin Scale score 0-2). Secondary outcomes included early neurological recovery (reduction in National Institutes of Health Stroke Scale score ≥8 points, or score of 0-1 at 24-hours), symptomatic intracranial hemorrhage, and 3-month mortality and modified Rankin Scale score. Results: Between January 2015 and December 2020, 784 patients were treated with EVT. There were 416 patients (213 men; mean±SD age 67.1±15.9) with cardioembolic LVO, including 221 (53.1%) prevalent AF, 99 (23.8%) incident AF, 48 (11.5%) mechanical heart valve, 10 (2.4%) cardiomyopathy-related LVO, 10 (2.4%) left ventricular thrombus-related LVO and 11 (2.6%) patent foramen ovale-related LVO patients. There was adequate anticoagulation in 8 (16.7%) mechanical heart valve patients. Of the 191 prevalent AF patients with pre-stroke indications for OAC, 59 (30.9%) patients had adequate anticoagulation, and were less likely to have internal carotid artery occlusion (6.8% versus 18.9%, P =0.03) and more likely to achieve functional independence (OR=1.97 [95% CI 1.01-3.83]; P =0.04) than those with inadequate anticoagulation. Conclusion: Over half of EVT treated patients had cardioembolic LVO. Only one-third of patients with an indication for OAC at the time of LVO were adequately anticoagulated. This suggests that up to one in five patients with LVO requiring EVT may have been prevented with adequate anticoagulation.

Bleeding and mortality risk in patients implanted with mechanical prosthetic heart valves with and without thrombocytopenia. Insights from the nationwide PLECTRUM registry

Previous studies showed that mechanical prosthetic heart valve (MPHV) patients may develop thrombocytopenia, but its association with clinical outcomes has not been investigated. We enrolled 1,663 patients with available platelet count from the multicenter nationwide retrospective PLECTRUM registry to investigate the association of thrombocytopenia with all-cause mortality and major bleeding (MB) in patients implanted with MPHV. Thrombocytopenia was defined by platelet count <150 × 109/L. Overall, 44.9% of patients were women and the mean age was 56.7 years. At baseline, 184 (11.1%) patients had thrombocytopenia. Patients with thrombocytopenia were more frequently men and elderly. Platelet count showed an age-dependent decline in men but not in women. We found an increased risk of death in patients with age ≥ 65 years, with a low anticoagulation quality, concomitant arterial hypertension, heart failure, a higher INR range, or with thrombocytopenia (OR 1.739, 95%CI 1.048–2.886, p = .032). At multivariable logistic regression, patients with age ≥65 years, concomitant AF and thrombocytopenia (OR 1.907, 95%CI 1.219–2.983, p = .005) had an increased risk of MBs. In MPHV patients, thrombocytopenia is associated with an increased risk of death and MB. There is a growing need for a sex- and age-specific threshold to define platelet count in adult patients.

Outcomes of leadless pacemaker implantation in patients with mechanical heart valves

Abstract Introduction Device-related infections constitute a major complication of transvenous pacemaker implantation. Mechanical heart valves (MHV) increase the risk of infective endocarditis (IE) and pacemaker infection, worsening their outcomes.Leadless pacemakers (LP) have been associated with low infection rates and thus pose an attractive option in MHV patients requiring permanent pacing. Methods and results This is a multicenter, observational, retrospective study including all consecutive patients implanted with an LP at 5 tertiary referral centers between June 2015 and January 2020.Procedural outcomes, complications, performance during follow-up and episodes of bacteremia and IE were recorded and compared between patients with and without a MHV (MHV and non-MHV groups).Four hundred fifty-nine patients were included (74 in the MHV group, 16.1%, and 385 in the non-MHV group, 83.9%).Implantation success, procedural outcomes and acute electrical performance were comparable between groups.Vascular complications and cardiac perforation occurred in 2.7 vs. 2.3% (p=1) and 0% vs. 0.8% (p=1) in the MHV group and non-MHV group, respectively.During a median post-implant follow-up of 308 days for the MHV group and 416 days for non-MHV patients (p=0.029), one case of IE was reported in the MHV group and 2 in the non-MHV group. All three occurred in patients with abandoned transvenous leads. Conclusion LP implantation is feasible and safe in patients with MHV, with procedural outcomes and electrical performance comparable to the general LP population. Device-related infections, including IE, are rare in patients receiving an LP, including those with an MHV. LP implantation should be considered in MHV patients with an indication for pacing. Funding Acknowledgement Type of funding sources: None. Procedural outcomes and complicationsBaseline and follow-up parameters

Efficacy and safety of low intensity vitamin K antagonists in Western and East-Asian patients with left-sided mechanical heart valves.

The optimal INR target in patients with mechanical heart valves is unclear. Higher INR targets are often used in Western compared with East Asian countries. The objective of this systematic review and meta-analysis was to summarize the evidence for the efficacy and safety of lower versus higher INR targets in Western and East Asian left-sided mechanical heart valve patients. We searched Western databases including Cochrane CENTRAL, Medline, and Embase as well as Chinese databases including SinoMed, CNKI, and Wanfang Data in addition to grey literature for Randomized Controlled Trials (RCTs) and observational studies. We pooled risk ratios (RRs) using random-effects model. Low and high INR targets were defined by the individual studies. We identified nine RCTs, including six Western (n = 5496) and three East Asian (n = 209) trials, and 17 observational studies, including two Western (n = 3199) and 15 East Asian (n = 5485) studies. In the RCTs, lower compared with higher targets were associated with similar rates of thromboembolism (2.4 vs. 2.3%; RR: 1.14, 95% CI 0.82, 1.60, I2 = 0%) and lower rates of both total bleeding (21.9 vs. 40.9%, RR: 0.46, 95% CI 0.28, 0.78, I2 = 88%) and major bleeding. RCT data showed no statistical heterogeneity by region. These effects were consistent in the observational data. We downgraded the quality of evidence due to serious risk of bias and imprecision. In patients with left-sided contemporary mechanical heart valves, low quality evidence suggests lower INR targets are associated with similar rates of thromboembolism and moderate quality evidence suggests lower rates of bleeding.

Mechanical heart valve patients switched to DOACs during COVID-19 pandemic to be reviewed 'urgently'

More than 700 patients with a mechanical heart valve who were switched to a direct oral anticoagulant (DOAC) during the pandemic should be reviewed “urgently” before 28 July 2021, a “safety critical” National Patient Safety Alert from NHS England has ordered. In March 2020, NHS England published guidance advising clinical teams to review patients taking […]

Effects of heparinoid bridging in patients with mechanical heart valves.

Patients with mechanical heart valves (MHVs) require long-term oral anticoagulation therapy to protect against thromboembolisms. Invasive procedures with high bleeding risks require oral anticoagulation therapy cessation. Currently, guidelines recommend the use of either subcutaneous low-molecular-weight heparin or intravenous unfractionated heparin in the perioperative period. It is unclear whether the evidence supports the use of one heparinoid over the other. To compare the effectiveness of low-molecular-weight heparin and unfractionated heparin bridging based on the adverse outcomes of thromboembolisms, major bleeding, and death during the perioperative period. A literature search was conducted using PubMed, EMBASE, CINAHL, and the Cochrane Library. Five studies comparing the two bridging therapies in chronically anticoagulated MHV patients met the inclusion criteria. No statistical significance was found for the endpoints of thromboembolism and death. One study found a statistically significant higher occurrence of major bleeding in patients treated with unfractionated heparin. In all the studies, major bleeding occurred more often than thromboembolisms. Findings were limited by the study designs and methodologies. Based on the available evidence, neither low-molecular-weight heparin nor intravenous heparin bridging was found to be more effective in reducing the occurrence of adverse events. This may be due in part to the study designs and lack of standardized bridging protocols used in the studies reviewed. Nurse practitioners should remain informed about bridging protocols and weigh the risk versus benefit of each bridging agent when caring for patients with MHVs.

EFFICACY AND SAFETY OF LOW INTENSITY VITAMIN K ANTAGONISTS IN WESTERN AND EAST-ASIAN POPULATIONS OF LEFT-SIDED MECHANICAL HEART VALVE PATIENTS

The optimal INR target with vitamin K antagonist (VKA) therapy in patients with mechanical heart valves is unclear. Although higher INR targets are often used in Western countries, data from randomized controlled trials (RCTs) have suggested that lower INR targets may offer reduced bleeding rates without a significant difference in thromboembolic rates. Lower INR targets are frequently used in East-Asia. The objective of this systematic review and meta-analysis was to evaluate the effects of lower versus higher INR targets in Western and East-Asian populations on rates of thromboembolism and bleeding in left-sided mechanical heart valve patients.

Prophylactic doses of low-molecular weight heparin as periprocedural bridging therapy in mechanical heart valve patients

BackgroundMechanical heart valve (MHV) patients undergoing invasive procedures necessitating an interruption of their lifelong anticoagulant therapy, often require bridging with low-molecular weight heparin (LMWH) or unfractionated heparin. The aim of this study was to assess whether bridging MHV patients with prophylactic doses of LMWH undergoing invasive, elective procedures is a safe and effective method. MethodThis observational cohort study included all MHV patients on vitamin K anticoagulant therapy in Malmö, registered and monitored via AuriculA (the Swedish national quality registry for atrial fibrillation and anticoagulation), between 1/1/2008 and 31/12/2011. Inclusion criteria were periprocedural bridging therapies conducted via AuriculA. Primary endpoints were mortality, thromboembolic (TE) events or major bleedings (MBE) within 30 days of bridging. ResultsDuring the study period, 210 patients had undergone 434 bridging therapies managed via AuriculA; 203 due to subtherapeutic INR-values were excluded. The remaining 231 periprocedural bridging therapies were included. All were bridged with prophylactic doses of LMWH. When comparing patients with aortic and/or mitral valve replacements undergoing low- or high-risk interventions, only number of days bridged for a low-risk intervention differed significantly. Patients with a mitral or mitral and aortic valve replacement were bridged for a longer period (p=0.023). No TE events, 1 death (0.4%) and 3 MBEs (1.3%) occurred related to periprocedural bridging. ConclusionOur study shows a low rate of MBEs, deaths and no TE events when bridging MHV patients undergoing invasive, elective procedures with prophylactic doses of LMWH.

Anticoagulant bridging in left-sided mechanical heart valve patients

BackgroundIn preparation for an invasive procedure with a high bleeding risk, patients with a mechanical heart valve temporarily have to discontinue their anticoagulant therapy and are usually bridged with either intravenous unfractionated heparin (UFH) or subcutaneous low-molecular-weight heparin (LMWH). In this study we retrospectively analyzed the safety of UFH versus LMWH as bridging strategy in left-sided mechanical heart valve patients. MethodsWe performed a retrospective multicenter study in four surgical centers in The Netherlands. Patients with a mechanical heart valve implantation bridged from January 2010 until January 2015 were included. The cumulative incidence of adverse events in the 30days following the procedure was recorded. Main outcomes were major bleeding according to International Society on Thrombosis and Haemostasis (ISTH) criteria, symptomatic thromboembolism, and mortality. ResultsIn total, 238 (174 aortic, 42 mitral, 22 aortic+mitral) bridging episodes were included. The incidence of major bleeding was 16 (19%) events in the UFH group versus 29 (19%) events in the LMWH group (p=0.97). Incidences of thromboembolism were 2 (2.4%) versus 1 (0.6%). The incidence of death was 1 (1.2%) patient in the UFH group versus 3 (1.9%) patients in the LMWH group. More than 50% of all bleeding complications were categorized as a major bleeding. ConclusionsBridging anticoagulation in patients with aortic and mitral mechanical valves is associated with considerable risk, but no difference was apparent between UFH and LMWH strategy. The rate of thromboembolism and death was low with either strategy and the vast majority of adverse events were bleedings.

Timing of vitamin K antagonist re-initiation following intracranial hemorrhage in mechanical heart valves: Systematic review and meta-analysis

BackgroundWhile evidence supports resumption of vitamin K antagonists (VKAs) among mechanical heart valve (MHV) patients presenting with anticoagulant-associated intracranial hemorrhage (ICH), ideal timing of resumption is uncertain. ObjectiveTo determine the optimal timing of VKA re-initiation and its associated clinical outcomes. MethodsWe performed a systematic review and a meta-analysis of studies published from January 1950 to August 2015. We extracted data on the location of initial ICH, use of cranial surgery, presence of atrial fibrillation, MHV type and position, number of MHVs, and timing of VKA resumption. Outcomes including valve thrombosis, thromboembolic events or ICH recurrence were recorded. Meta-regression analysis was conducting with controlling for covariates. We calculated absolute risks, and assessed the effect of anticoagulant resumption timing on ICH recurrence. Results23 case-series and case-reports were identified. Overall ICH recurrence was 13% (95% confidence interval [CI], 7%–25%), while valve thrombosis and ischemic strokes occurred at 7% (95% CI, 3%–17%) and 12% (95% CI, 5%–23%) respectively. A trend towards lower ICH recurrence was observed with delayed VKA resumption (slope estimate −0.2154, p=0.10). Recurrence rate ranged from 50% with VKA resumption at 3days to 0% with resumption at 16days. ConclusionAmong patients with MHV, there is inadequate data to suggest an optimal timing of VKA re-initiation following an ICH, though delayed restart appears to be protective against recurrence but is associated with higher risk of thrombosis. Our analysis suggests 4–7days might be an ideal time with least risk of thrombosis or ICH recurrence.

Self-Management of Anticoagulant Therapy in Mechanical Heart Valve Patients: A Matched Cohort Study

Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists for mechanical heart valves has demonstrated efficacy in randomized controlled trials. However, the effectiveness of PSM in clinical practice has only been investigated in small trials. Our aim was to evaluate the effectiveness of PSM of oral anticoagulant therapy in mechanical heart valve patients. We conducted a matched cohort study: cases were patients with a mechanical heart valve performing PSM affiliated with Aarhus University Hospital or Aalborg University Hospital, Denmark, in the period 1996 to 2012 (n = 615). Prospectively registered patient data were obtained from databases at two hospitals, and cross linkage between these databases and national patient registries provided detailed information on comorbidities and events. Control patients were matched (on sex, date of birth, year of first valve surgery, and grouped valve position) in a ratio of 5:1 (n = 3,075) with patients receiving conventional management who were randomly selected within the match group. The effectiveness and safety was estimated using major bleeding and thromboembolic events and death as outcomes. We observed low event rates in the PSM group. After 5 years, PSM was associated with a lower risk of all-cause mortality compared with conventional management (adjusted hazard ratio of 0.49, 95% confidence interval: 0.34 to 0.71). The hazard ratios for thromboembolism and major bleeding were 0.91 (95% confidence interval: 0.66 to 1.24) and 0.83 (95% confidence interval: 0.56 to 1.22). Owing to superior clinical effectiveness, self-managed oral anticoagulant therapy may potentially improve the standard of care for patients with mechanical heart valves.

A case series of LMWH use in pregnancy: Should trough anti-Xa levels guide dosing?

IntroductionPregnancy is a thrombogenic state, increasing the risk for venous thromboembolism (VTE), and the risk of valve thrombosis amongst women with mechanical heart valves (MHV). While low molecular weight heparins (LMWH) are generally dosed based on weight (i.e., enoxaparin 1mg/kg every 12hours), data in pregnant women have shown that weight-based dosing does not consistently achieve target anti-Xa levels. In women with MHV, our practice includes titrating LMWH doses to target both trough and peak anti-Xa levels, while for those with VTE peak anti-Xa levels guide dosing. Materials/MethodsThis retrospective case series included pregnant women requiring LMWH treatment doses with at least 3 peak (+/−trough) anti-Xa levels. Our primary objective was to describe the actual LMWH dose required to achieve targeted anti-Xa levels relative to weight-based dosing in patients with MHV. Secondarily, we compared the same for VTE patients; compared actual dosing between those with MHV and VTE; and examined maternal and fetal outcomes. Results/ConclusionWomen with MHV (N=4) required greater than weight-based dosing of enoxaparin (1.35mg/kg Q12H) to achieve targeted anti-Xa levels. Importantly, achieving target peak anti-Xa levels did not always ensure maintenance of minimum trough levels. VTE patients (N=12) did not require more enoxaparin (0.96mg/kg Q12H) than weight based dosing. MHV patients received more enoxaparin compared to VTE patients (P<0.001). No bleeding or clotting complications were associated with LMWH administration. In pregnant women with MHV at high risk of thromboembolism, LMWH dosing guided by trough and peak anti-Xa levels should be considered.