[Practice guidelines of the Spanish Society of Cardiology. Recommendations for the use of antithrombotic treatment in cardiology]

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

BACKGROUND

While 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.

OBJECTIVE

To determine the optimal timing of VKA re-initiation and its associated clinical outcomes.

METHODS

We 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.

RESULTS

23 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.

CONCLUSION

Among 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.

Outcomes and safety of antithrombotic treatment in patients aged 80 years or older with nonvalvular atrial fibrillation

Our aim was to evaluate the effectiveness of oral anticoagulation (OAC) in patients aged ≥80 years with nonvalvular atrial fibrillation in daily clinical practice. From February 1, 2000 to June 30, 2009, we enrolled all patients aged ≥80 years with nonvalvular atrial fibrillation attended at 2 outpatient cardiology clinics of a tertiary care university hospital. The patients received antithrombotic treatment according to the recommendations from scientific societies and were prospectively followed, with major events (i.e., all-cause death, stroke, transient ischemic attack, peripheral embolism, severe bleeding) analyzed according to the treatment group (OAC vs no OAC). Of 269 patients included in the present study (87 men, mean age 83 ± 3 years), 164 received OAC (61%). After 2.8 ± 1.9 years of follow-up, the raw rates (per 100 patient-years) of embolic events (1.52% vs 8.30%, p <0.0001) and mortality (6.67% vs 10.94%, p = 0.04) were lower for patients receiving OAC, with a nonsignificant greater rate of severe bleeding (3.03% vs 1.25%, p = 0.14). The probability of survival free of major embolic or hemorrhagic events at the mean follow-up was greater for patients receiving OAC (82.27% vs 66.10%, p = 0.004). After adjustment for age, gender, coronary heart disease, and embolic risk, evaluated using the CHADS(2) score (congestive heart failure, 1 point; hypertension [blood pressure consistently >140/90 mm Hg or hypertension medication], 1 point; age ≥75 years, 1 point; diabetes mellitus, 1 point; previous stroke or transient ischemic attack, 2 points), only OAC was an independent predictor of embolic events (hazard ratio 0.17, 95% confidence interval 0.07 to 0.41, p <0.001). The CHADS(2) score (hazard ratio 1.32, 95% confidence interval 1.01 to 1.73, p = 0.04) and OAC (hazard ratio 0.52, 95% confidence interval 0.31 to 0.88, p = 0.01) were independent predictors of mortality. In conclusion, OAC according to the scientific societies' recommendations is effective and safe in daily clinical practice, even in patients aged ≥80 years.

Anticoagulación oral en la fibrilación auricular no valvular: ¿son efectivas y seguras las recomendaciones científicas en la práctica clínica diaria?

INTRODUCTION AND OBJECTIVES

To study the efficacy and safety of an oral anticoagulation protocol for the treatment of nonvalvular atrial fibrillation, based on scientific associations' recommendations, in unselected patients seen in daily clinical practice.

METHODS

The study included all consecutive patients with permanent nonvalvular atrial fibrillation who attended two outpatient cardiology clinics between February 1, 2000 and February 1, 2002. They were treated according to an anticoagulation protocol based on Spanish Society of Cardiology and American College of Cardiology/American Heart Association/European Society of Cardiology guidelines. Patients were followed up prospectively for major events, such as death, stroke, transient ischemic attack, peripheral embolism and severe hemorrhage, which were recorded by treatment group.

RESULTS

A total of 624 patients were included in the study. Those receiving anticoagulation therapy (n=425; 68%) more frequently had hypertension, diabetes and previous embolism as well as a greater number of cardioembolic risk factors (P< .001). Overall, 93% of non-anticoagulated patients received platelet aggregation inhibitors (92% received aspirin). After a median follow-up of 21 months, the probability of an embolic event was lower in anticoagulated patients (0.81% vs 14.04%; P< .001), as was all-cause mortality (3.27% vs 6.42%; P=.003). However, there was no significant difference in the probability of severe bleeding (2.75% vs 2.93%; P=.96). Results were unchanged after adjustment for age, sex, and previous embolic events.

CONCLUSIONS

Oral anticoagulation therapy for nonvalvular atrial fibrillation implemented according to scientific associations' recommendations is effective and safe in daily clinical practice.

Magnitude and consequences of undertreatment of high-risk patients with non-ST segment elevation acute coronary syndromes: insights from the DESCARTES Registry

OBJECTIVE

To analyse intensity of treatment of high-risk patients with non-ST elevation acute coronary syndromes (NSTEACS) included in the DESCARTES (Descripción del Estado de los Sindromes Coronarios Agudos en un Registro Temporal Español) registry.

PATIENTS AND SETTING

Patients with NSTEACS (n = 1877) admitted to 45 randomly selected Spanish hospitals in April and May 2002 were studied.

DESIGN

Patients with ST segment depression and troponin rise were considered high risk (n = 478) and were compared with non-high risk patients (n = 1399).

RESULTS

46.9% of high-risk patients versus 39.5% of non-high-risk patients underwent angiography (p = 0.005), 23.2% versus 18.8% (p = 0.038) underwent percutaneous revascularisation, and 24.9% versus 7.4% (p < 0.001) were given glycoprotein IIb/IIIa inhibitor. In-hospital and six-month mortality were 7.5% versus 1.1% and 17% versus 4.6% (p < 0.001), respectively. A treatment score (> or = 4, 2-3 and < 2) was defined according to the number of class I interventions recommended in clinical guidelines: aspirin, clopidogrel, beta blockers, angiotensin-converting enzyme inhibitors, statins and revascularisation. Independent predictors of six-month mortality were age (odds ratio (OR) 1.07, 95% confidence interval (CI) 1.04 to 1.10, p < 0.001), diabetes (OR 1.92, 95% CI 1.14 to 3.22, p = 0.014), previous cardiovascular disease (OR 4.17, 95% CI 1.63 to 10.68, p = 0.003), high risk (OR 2.20, 95% CI 1.30 to 3.71, p = 0.003) and treatment score < 2 versus > or = 4 (OR 2.87, 95% CI 1.27 to 6.52, p = 0.012).

CONCLUSIONS

Class I recommended treatments were underused in high-risk patients in the DESCARTES registry. This undertreatment was an independent predictor of death of patients with an acute coronary syndrome.

Evaluación del programa piloto de descentralización del control del tratamiento anticoagulante oral en el Servicio Navarro de Salud-Osasunbidea

BACKGROUND AND OBJECTIVE

The objective of this study was the evaluation of the pilot programme of decentralization of oral anticoagulant therapy (OAT) in eight basic health zones (ZBS) for the first six months and then a year after the programme was put into practice.

PATIENTS AND METHOD

Descriptive transversal study. It includes all patients aged 14 years or older in the OAT (540 in the initial period and then 640 more) in eight ZBS (five urban and three rural). The evaluation was done including: prevalence of INR in control (2-3 or 2.5-3.5, according to indications), clinically suitable INR (INR in control +/- 0.2) and INR in control +/- 0.5, accumulated thrombosis and bleeding incidence. Source data: ANTICOAGN computer programme.

RESULTS

Comparison of INR control between both periods: 59% against 63.9% of INR in the range of INR in control (p < 0.001), 72.8% against 78.8% for clinically suitable INR (p < 0.001), and 86.6% against 91.4% for INR in control +/- 0.5 (p < 0.001). Accumulated incidence of bleeding episodes in 6 months: Pilot: 1.1% (0.7% majors and 0.4% minors). Subsequent period: 3.6% (0.6% majors and 3% minors).

CONCLUSIONS

The decentralization of control of the OAT with adequate resources implies a greater accessibility for the patient. The control of INR is acceptable and has improved significantly over the second period. We have detected an improvement in the increase of the INR below that of the range of the control INR. The incidence of minor hemorrhages has increased, owing probably to a better recording.

[How suitable is thromboembolism prophylaxis for patients with chronic auricular fibrillation at 3 primary care centers]

OBJECTIVE

To find just how suitable thromboembolism prophylaxis (TEP) is in a group of patients with chronic auricular fibrillation belonging to the primary care environment.

DESIGN

Cross-sectional and descriptive multi-centre study.

SETTING

The study was performed at 3 urban primary care centres in Madrid.

PARTICIPANTS

All the patients recorded up to April 2001 with the diagnosis of chronic auricular fibrillation (n=274) were included. Patients with no clinical history or who had a valve prosthesis were excluded.

MAIN MEASUREMENTS

Demographic variables, existence of factors of risk of embolism, presence of counter-indications for oral anti-coagulants, and the kind of thromboembolic prophylaxis taken were collected.

RESULTS

A total of 274 patients were evaluated. Average age was 75 (SD, 9) and 52% were women. 82% of patients had at least one factor of risk of thromboembolism. The most commonly used kind of TEP was oral anti-coagulants. 45% of patients did not receive suitable TEP. 13.5% of patients at risk of embolism and who had no kind of TEP were found.

CONCLUSIONS

There is a high percentage of patients with chronic auricular fibrillation and a high risk of embolism, who do not receive adequate TEP, in the absence of counter-indications to taking oral anticoagulants. There is great scope for improvement, which is within professionals' possibilities.

Ought dialysis patients with atrial fibrillation be treated with oral anticoagulants?

BACKGROUND

Dialysis patients with atrial fibrillation have an increased thrombolic risk. Dicoumarin anticoagulant therapy is often considered contra-indicated in chronic renal insufficiency in which the risk of haemorrhage, though not defined, is perceived to be high. We assessed haemorrhage complications in dialysis patients receiving dicoumarin anticoagulant therapy to establish whether the haemorrhage risk justifies the contra-indication of anticoagulant therapy in patients with atrial fibrillation.

PATIENTS AND METHODS

Over a period of a decade in our dialysis centre, 29 patients receiving anticoagulant therapy over a protracted period presented haemorrhage complications. These were classified with respect to severity and location and compared with 211 patients not receiving anticoagulant therapy. The relative risk of haemorrhage was calculated and was compared to risk of thrombo-embolism in dialysis patients with atrial fibrillation.

RESULTS

Of the 29 patients, nine had 13 episodes of haemorrhage complications (26 episodes/100 patient-years). None was fatal, nor intra-cranial nor with serious clinical sequelae. In the group without anticoagulants, 29 patients had 39 haemorrhage complications (11 episodes/100 patient-years); four (10.2%) intra-cranial and all fatal. The relative risk of bleeding with anticoagulant therapy was 2.36 (95% confidence interval=1.19-4.27).

CONCLUSIONS

(1) Dialysis patients with anticoagulant therapy presented with a higher risk of haemorrhage; (2) the relative risk of bleeding was double that of the dialysis population without anticoagulant therapy; (3) despite the high risk of haemorrhage that we observed, the high risk of thrombo-embolism and the attendant serious sequelae to which dialysis patients with atrial fibrillation are predisposed indicates that oral anticoagulation therapy ought not to be considered automatically contra-indicated in this patient group but that an exhaustive evaluation of the risk-benefit needs to be conducted on an individual patient basis.

Uso de anticoagulación al alta hospitalaria en pacientes con insuficiencia cardíaca y fibrilación auricular

INTRODUCTION AND OBJECTIVES

To assess the degree of compliance with current guidelines for chronic anticoagulation in patients with heart failure and atrial fibrillation.

PATIENTS AND METHOD

From the INCARGAL Study database, we analyzed data from 195 consecutive patients (88 men; mean age 76 10 years) with both conditions, admitted to three Galician hospitals between January and March 1999. It was assumed that these patients should have received anticoagulant therapy at discharge, unless contraindicated. We studied the association of treatment at discharge (anticoagulation or not) with the presence or absence of contraindications.

RESULTS

152 patients (78%) had no contraindication for anticoagulation and 43 had at least one (absolute: 11, relative: 32). Only 50% of patients without contraindications received anticoagulation at the time of discharge. No patient with an absolute contraindication and 3 with a relative one received anticoagulation. Factors related with the less frequent prescription of anticoagulation therapy in patients without a formal contraindication were: age, a previous history of coronary heart disease, absence of valvular heart disease, prior myocardial infarction, treatment with beta-blocking agents, non performance of an echocardiogram, and admission to a department other than cardiology. On multivariate analysis, age, prior myocardial infarction, and non-valvular disease were found to be independent predictors of less use of anticoagulation.

CONCLUSIONS

Anticoagulant therapy is used less often than recommended at discharge in patients with heart failure and atrial fibrillation for whom there were no contraindications. Advanced age reduces its use. The presence of other indications for antiplatelet or anticoagulation therapy appears to determine the choice of one or the other. Noncompliance with the guidelines due to overprescription was not found.

Patrones clínicos de presentación de la fibrilación auricular en los pacientes hospitalizados

INTRODUCTION AND OBJECTIVES

The ACC/AHA/ESC 2001 guidelines for the management of atrial fibrillation (AF) establish 4 categories: first episode, paroxysmal, persistent and permanent. The aim of this study was to analyze the frequency of the different clinical patterns of presentation of AF in hospitalized patients.

PATIENTS AND METHOD

We analyzed the pattern of AF in 300 hospitalized patients, 200 of whom were admitted to the cardiology and 100 to the internal medicine department. We determined the clinical profile and evaluated the factors influencing therapeutic management.

RESULTS

The permanent form was present in 30% of the patients admitted to the cardiology department and in 51% if those admitted to the internal medicine department. The first episode pattern was the most frequent in cardiology department patients (41%). In patients hospitalized the in cardiology the percentage use of anticoagulants (57.9% vs. 41%; p < 0.01) and beta blockers was greater than in internal medicine patients, and digitalis use was lower. In the multivariate analysis, admission to the cardiology department was an independent predictor of treatment with beta blockers (OR = 3.8; 95% CI, 1.3-11.1; p < 0.05), and discharge from the hospital with AF was a predictor of anticoagulant prescription (OR = 4.8; 95% CI, 2.5-9.2; p < 0.001).

CONCLUSIONS

a) Atrial fibrillation is an arrhythmia with a heterogeneous clinical pattern that varies depending on the type of care provided; b) on admission to cardiology, only 30% of the patients present with permanent arrhythmia, and the most frequent clinical pattern is first episode; and c) discharge from the hospital with AF was the principal determinant of therapeutic management.

Utilización de anticoagulantes orales en pacientes con fibrilación auricular al alta hospitalaria en el año 2000

INTRODUCTION AND OBJECTIVES

Although there is consensus about the use of oral anticoagulants to prevent thrombi and embolisms in most patients with atrial fibrillation, this treatment is underused in actual practice. Our objective was to determine and analyze the use of acenocoumarol in patients diagnosed as having atrial fibrillation at discharge.

PATIENTS AND METHOD

Between January and July 2000, we retrospectively studied 501 consecutive patients with a diagnosis of atrial fibrillation. We recorded whether they were discharged with or without oral anticoagulation treatment.

RESULTS

We identified 482 patients with at least one associated thromboembolic risk factor, who comprised the study population. Mean age was 79.3 years, and 33.3% of the patients were men. Forty-six percent were discharged with acenocoumarol, and 36.3% with platelet antiaggregants. Twenty-three percent had a known contraindication for acenoroumarol. Nearly 62% of the patients without contraindications for anticoagulation received treatment with acenocoumarol. Multivariate analysis showed that rheumatic mitral valve disease, previous stroke or thromboembolism and dilated left atrium were associated with a higher probability of receiving anticoagulant treatment. Age over 75 years was associated with a lower likelihood of receiving acenocoumarol.

CONCLUSIONS

Oral anticoagulation was given in an inadequate proportion of patients who were discharged from a secondary-level hospital with atrial fibrillation and no contraindications. Rheumatic mitral valve disease, previous stroke or thromboembolism, and dilated left atrium were associated with a higher probability of anticoagulant treatment. Age over 75 years was related with less frequent use of this therapy.

Un protocolo prospectivo permite incrementar la utilización de anticoagulación oral en pacientes con fibrilación auricular crónica no valvular

INTRODUCTION AND OBJECTIVES

Observational studies have shown that oral anticoagulants (OAC) prescription is suboptimal in patients with nonvalvular atrial fibrillation (NVAF). Our objective was to evaluate the usefulness of a prospective protocol for increasing OAC usage in these patients.

PATIENTS AND METHOD

From 1 February 2000 until 31 October 2002 we enrolled all patients with chronic NVAF seen in two outpatient cardiology clinics, excluding candidates for cardioversion. Each patient was studied to identify cardioembolic risk factors (CERF) and contraindications for OAC. Anticoagulation was suggested to all patients with > or =2 CERF and without contraindications for OAC. The decision to prescribe OAC was made by the physician in charge when there was only one CERF.

RESULTS

721 patients fulfilled the inclusion criteria. Mean age was 73 +/- 8 years; 44% were men. In most cases NVAF was related with hypertension (57%), followed by no structural heart disease (25%) or ischemic heart disease (9%). The most frequent CERFs were hypertension (66%), age > or =75 years (45%) and diabetes (24%). A total of 663 patients had > or =1 CERF (92%), and 125 (19%) of these presented at least one contraindication for OAC. Of the 538 remaining patients (90%), 485 (67% of the whole series) were treated with anticoagulation. Of the patients with > or =2 CERF and without contraindications for OAC, 95% were treated.

CONCLUSIONS

A prospective protocol for use in the outpatient cardiology clinic allows to prescribe OAC in a large percentage of patients with NVAF.

[Identification of factors responsible for oral over-anticoagulation in outpatients with heart disease]

BACKGROUND

Few studies have attempted to investigate the clinical course or identify factors responsible for excessive anticoagulation in patients with heart disease.

OBJECTIVES

To determine the incidence of excessive anticoagulation in outpatients with heart disease treated with acenocoumarol, analyze the factors related with over-anticoagulation, and identify bleeding complications.

PATIENTS AND METHOD

This 7-month prospective observational study included consecutive outpatients anticoagulated with acenocoumarol. They were seen in an anticoagulation unit. The high INR group of 55 over-anticoagulated patients had at least one test with INR > 5. The control group of 49 patients had INR results strictly within therapeutic range.

RESULTS

A total of 3,683 INR determinations were made in 512 patients. Seventy-seven tests had an INR > 5 (a 2% overall incidence of high-INR). In the group of 55 INR < 5 patients, 31% had more than one INR determination > 5 during follow-up. Multivariate analysis identified four variables as independent predictors of over-anticoagulation: artificial heart valve, poor treatment compliance, addition of potentially interactive new drugs, and illness in the last month. The high-INR group patients had more bleeding episodes (21.8 vs 4.08%; p = 0.008), one of which was major.

CONCLUSION

The incidence of excessive oral anticoagulation in our outpatient population was similar to that reported in other studies. Patients with INR > 5 had more total bleeding complications, mostly minor. It is recommended to proceed carefully with oral anticoagulant therapy in patients with an artificial heart valve, suspected poor treatment compliance, addition of potentially interactive new drugs, and illness in the last month.

[Antithrombotic treatment in hypertensive patients with chronic atrial fibrillation. CARDIOTENS 99 study]

BACKGROUND

Our main goals were to know the actual degree of oral anticoagulation and antiaggregation in hypertensive patients with atrial fibrillation in the daily clinical practice in Spain and to analyze any differences between primary care physicians and cardiologists.

PATIENTS AND METHOD

32,051 outpatients attended the same day by 1,159 physicians (21% cardiologists) were prospectively included in a database taking into account a history of hypertension and atrial fibrillation, demographic data and ongoing treatments.

RESULTS

Hypertension was detected in 10,555 patients and 999 of them had both hypertension and atrial fibrillation (9.46%: 435 males [44%] and 564 females [56%]). 53% patients were attended by primary care physicians and the rest by cardiologists. 33% of hypertensive patients with atrial fibrillation were on oral anticoagulation: 41% of them attended by cardiologists and 26% by primary care physicians (p < 0.05). These differences persisted when the patients were compared on the basis of their age. 39% of hypertensive patients were on oral antiaggregation treatment, without differences in both groups except for those aged less than 65 years who were found to receive more antiaggregation in primary care (36% vs 24%; p < 0.05).

CONCLUSIONS

The prevalence of atrial fibrillation in hypertensive patients is about 10%; there is a suboptimal degree of utilization of oral anticoagulation, which is more evident in patients attended by primary care physicians; elderly patients (> 80 years-old) were found to receive less anticoagulants and more antiaggregants both in primary health-care and cardiology health-care.

[The efficacy of scheduled cardioversion in atrial fibrillation. Comparison of two schemes of treatment: electrical versus pharmacological cardioversion]

INTRODUCTION AND OBJECTIVES

Atrial fibrillation is an arrhythmia with high morbidity and mortality. Restoring sinus rhythm is one of the principle objectives in its management. The present study aimed to assess the efficacy of scheduled cardioversion on atrial fibrillation by comparing two different therapeutic approaches: electrical vs. pharmacological cardioversion.

PATIENTS AND METHOD

Two hundred thirty patients with atrial fibrillation of more than 48 hours duration and requiring sinus rhythm restoration were included. One hundred forty-four patients underwent external electrical cardioversion and 86 patients received quinidine. We analyzed the rate of success, duration of hospital stay, complications and clinical and echocardiographic variable that might predict success.

RESULTS

Sinus rhythm was restored in 181 of 230 patients (79%). The rate of success was 77% (111/144 patients) in the electrical group and 81% (70 of 86 patients) in the pharmacological group (ns). In 13 pharmacological group patients for whom the first attempt failed attempt, a second attempt with electrical cardioversion was made and was successful in 8 patients (61%). No embolic complication was recorded and only two electrical disturbances were seen. Only atrial fibrillation lasting less than 8 weeks was associated with a higher success rate (p < 0.01).

CONCLUSIONS

Scheduled cardioversion in atrial fibrillation is an effective technique with a high success rate and a very low rate of complication. Electrical cardioversion and pharmacological cardioversion with quinidine are similarly effective, although the latter involves a longer hospital stay.

[Oral anti-coagulants in an urban health centre. The first years results]

OBJECTIVES

To assess the management of oral anti-coagulation treatment (OAT) by family doctors and nurses from a health centre (HC) during its first year.

DESIGN

Descriptive cross-sectional study.Setting. La Chana, an urban HC in Granada, covering 19,362 inhabitants in family care units.

PARTICIPANTS

220 patients with acenocumarol prescribed during the year 2000. The criterion for inclusion was to have at least 3 OAT check-ups a year. 24 people were excluded.Interventions. Recruitment by personal invitation at the clinic. Capillary blood analyses and dose adjustments by the 10 nurses and 10 family doctors of the HC. Internationally recognised therapeutic ranges.

MAIN MEASUREMENTS

Prevalence of OAT: prescriptions of acenocumarol. Recruitment: patients monitored at the HC.

INDICATIONS

those found in the clinical records. Monitoring: % of patients with INR within range in final annual check-up.

COMPLICATIONS

rate of haemorrhages, thrombo-embolic accidents and other secondary effects.

RESULTS

196 patients followed OAT, a prevalence of 10.12 per thousand, with 19.6 patients per family doctor. The HC monitored 122 (62.24%); and the hospital, 74 (37.76%). The HC carried out 1,224 check-ups, 208 in the homes of 21 patients. There were 70.5% within the therapeutic range. Only 13% were in a situation of dose adjustment. Most common indications: non-rheumatic auricular fibrillation 65, TVP/TEP 27, mechanical cardiac prostheses 22. There were no fatal haemorrhages. Major haemorrhages ran at 2.22% of patients a year; and minor ones, at 6.68%. There were no thrombo-embolic accidents. There were two skin allergies.

CONCLUSIONS

The study showed good results, in line with the findings of other studies.

Cost-effectiveness analysis of enoxaparin versus unfractionated heparin in the secondary prevention of acute coronary syndrome

BACKGROUND

The Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q-Wave Coronary Events (ESSENCE) and Thrombolysis in Myocardial Infarction (TIMI) 11B studies revealed that enoxaparin reduced the incidence of death, myocardial reinfarction and recurrent angina in patients with acute coronary syndrome (ACS) compared with unfractionated heparin (UFH).

OBJECTIVE

To perform a pharmacoeconomic analysis to evaluate the cost effectiveness of treatment with enoxaparin compared with UFH in Spanish patients with ACS.

DESIGN AND SETTING

Retrospective cost-effectiveness analysis using data and costs from Spanish sources, conducted from the perspective of the National Health System. PATIENTS, INTERVENTIONS AND OUTCOMES MEASURES: The study was based on the results of the ESSENCE and TIMI 11B clinical trials, which included more than 7,000 patients with ACS treated with enoxaparin or UFH. The main variables studied were the success rate, expressed as patients with no complications (reinfarction, unstable angina or death), and the decrease in the utilisation of healthcare resources (revascularisation procedures and hospitalisation).

RESULTS

The base-case results of the analysis showed superior efficacy and lower total treatment and follow-up costs with enoxaparin compared with UFH. The total savings in direct health costs per patient with enoxaparin ranged between 448 and 659 euros (time horizons of 1 month and 1 year, respectively) [2001 values]. The sensitivity analysis results confirmed the advantage of enoxaparin in all cases, except in one scenario: when simultaneously using all the minimum values of the confidence interval for absolute risk reduction (ARR) in the utilisation of health resources.

CONCLUSIONS

This study suggests that enoxaparin is a more effective and less expensive treatment option than UFH in secondary prevention of patients with ACS in Spain, confirming the results obtained in other pharmacoeconomic analyses performed in the UK, USA, France and Canada.

[Prosthetic valve thrombosis: which is the most appropriate initial therapy?]

INTRODUCTION AND OBJECTIVES

This study aims to investigate what is the best initial therapy for patients with obstructive prosthetic valve thrombosis.

METHODS

Data from 47 patients diagnosed with prosthetic valve thrombosis in two tertiary hospitals during an 8-years period were analyzed.

RESULTS

The involved prostheses were in mitral position in 34 cases (2 biological valves), in aortic position in 12, and in double mitral and aortic position in one. The thrombosis was not obstructive in 12 patients. In the remaining 35 patients, the prosthetic obstruction was treated by heparin (n = 2), thrombolysis (n = 19), or direct surgery (n = 14). There was no mortality in the thrombolytic group, although 6 patients needed surgery before discharge because of an abnormal prosthetic residual gradient (n = 5) or a persisting abnormal disc valve motion (n = 1). Five out of 14 patients of direct surgery died, 2 before the planned operation could be performed. Thus, mortality rate, in an intention to treat analysis, was very favourable to thrombolytic therapy (p = 0.008); and this, despite the higher index of clinical severity (on a scale from 0 to 4) was superior in this group of thrombolyzed patients: 3.3 0.6 vs. 2.1 0.9 in those who underwent surgery; p < 0.0001.

CONCLUSIONS

In terms of mortality rate, thrombolysis is a better alternative than direct surgery to fight against obstructive prosthetic valve thrombosis. Even if the result is suboptimal, it allows the performance of surgery in better clinical conditions and, thus, with minor risk.

[Thrombogenic and endothelial damage markers in patients with ischemic systolic impairment]

INTRODUCTION

Anticoagulation is rarely indicated in patients with left ventricular dysfunction who show an increased risk for thromboembolism. In theory, the three arms of the Virchow' triad may be present: abnormal blood flow, endothelial damage and prothrombotic markers. The aim of this study was to identify the last two arms.

PATIENTS AND METHOD

We studied 82 consecutive patients with demonstrated ischaemic heart disease and sinus rhythm, and compared them with a control group comprised of 32 healthy subjects matched for age and sex. None or the patients had had an acute coronary event or hemodynamic decompensation within the 3 months prior to inclusion in the study. The plasma concentration or von Willebrand factor and fibrin d-dimer and fibrinogen were determined as endothelial damage and prothrombotic markers, respectively. A fractional shortening less than 29% by echography was defined as ventricular systolic dysfunction.

RESULTS

The patients showed significantly higher levels of von Willebrand factor with respect to the control group (109.2 31.9 vs 85.5 32.6%, p < 0.01), with no differences in fibrinogen and fibrin d-dimer values. Twenty-six patients fulfilled criteria of left ventricular systolic dysfunction. Patients with left ventricular dysfunction showed higher fibrinogen (386 118 vs 322 102 mg/dl, p = 0.03) and fibrin d-dimer (0.36 0.22 vs 0.26 0.10 g/ml; p = 0.04) levels, with no differences in von Willebrand factor levels.

CONCLUSIONS

After acute coronary events, patients with ischaemic heart disease show markers of endothelial damage. However, patients with left ventricular dysfunction show a hypercoagulable state.

[The efficacy of platelet IIb/IIIa receptor blockers in acute coronary syndromes]

The knowledge of the central role of platelets in the pathogenesis of acute coronary syndromes, on the one hand, and the fact that aspirin is a weak antiplatelet agent on the other, have led to an intensive investigational activity in antiplatelet drugs in the last years. Actually, the literature in the last two years is inundated with studies on the use of platelet IIb/IIIa receptor blockers in different clinical settings. Agents that block the IIb/IIIa platelet receptor have shown to be useful in improving prognosis of patients with acute coronary syndromes, especially in those undergoing percutaneous coronary revascularization procedures. However, their potential risk of bleeding and their high cost have prevented them from being applied universally and routinely. Furthermore there are still some unclear issues regarding the use of these drugs such as their correct dosage, the optimal duration of treatment and the direct comparison of the efficacy of different types of IIb/IIIa blockers available. On the other hand, oral IIb/IIIa antagonists have not improved the efficacy of aspirin to date and, moreover, they have been proven to be unsafe. Finally, it is necessary to identify those patients who will obtain the greatest benefit from the treatment in order to avoid the unnecessary risks and costs that would be derived from their universal use.