Irbesartan in patients with atrial fibrillation.

BACKGROUND: The risk of cardiovascular events among patients with atrial fibrillation is high. We evaluated whether irbesartan, an angiotensin-receptor blocker, would reduce this risk. METHODS: We randomly assigned patients with a history of risk factors for stroke and a systolic blood pressure of at least 110 mm Hg to receive either irbesartan at a target dose of 300 mg once daily or double-blind placebo. These patients were already enrolled in one of two trials (of clopidogrel plus aspirin versus aspirin alone or versus oral anticoagulants). The first coprimary outcome was stroke, myocardial infarction, or death from vascular causes; the second was this composite outcome plus hospitalization for heart failure. RESULTS: A total of 9016 patients were enrolled and followed for a mean of 4.1 years. The mean reduction in systolic blood pressure was 2.9 mm Hg greater in the irbesartan group than in the placebo group, and the mean reduction in diastolic blood pressure was 1.9 mm Hg greater. The first coprimary outcome occurred at a rate of 5.4% per 100 person-years in both groups (hazard ratio with irbesartan, 0.99; 95% confidence interval [CI], 0.91 to 1.08; P=0.85). The second coprimary outcome occurred at a rate of 7.3% per 100 person-years among patients receiving irbesartan and 7.7% per 100 person-years among patients receiving placebo (hazard ratio, 0.94; 95% CI, 0.87 to 1.02; P=0.12). The rates of first hospitalization for heart failure (a prespecified secondary outcome) were 2.7% per 100 person-years among patients receiving irbesartan and 3.2% per 100 person-years among patients receiving placebo (hazard ratio, 0.86; 95% CI, 0.76 to 0.98). Among patients who were in sinus rhythm at baseline, there was no benefit of irbesartan in preventing hospitalization for atrial fibrillation or atrial fibrillation recorded on 12-lead electrocardiography, nor was there a benefit in a subgroup that underwent transtelephonic monitoring. More patients in the irbesartan group than in the placebo group had symptomatic hypotension (127 vs. 64) and renal dysfunction (43 vs. 24). CONCLUSIONS: Irbesartan did not reduce cardiovascular events in patients with atrial fibrillation. (Funded by Bristol-Myers Squibb and Sanofi-Aventis; ClinicalTrials.gov number, NCT00249795.).

Dose comparisons of clopidogrel and aspirin in acute coronary syndromes.

BACKGROUND: Clopidogrel and aspirin are widely used for patients with acute coronary syndromes and those undergoing percutaneous coronary intervention (PCI). However, evidence-based guidelines for dosing have not been established for either agent. METHODS: We randomly assigned, in a 2-by-2 factorial design, 25,086 patients with an acute coronary syndrome who were referred for an invasive strategy to either double-dose clopidogrel (a 600-mg loading dose on day 1, followed by 150 mg daily for 6 days and 75 mg daily thereafter) or standard-dose clopidogrel (a 300-mg loading dose and 75 mg daily thereafter) and either higher-dose aspirin (300 to 325 mg daily) or lower-dose aspirin (75 to 100 mg daily). The primary outcome was cardiovascular death, myocardial infarction, or stroke at 30 days. RESULTS: The primary outcome occurred in 4.2% of patients assigned to double-dose clopidogrel as compared with 4.4% assigned to standard-dose clopidogrel (hazard ratio, 0.94; 95% confidence interval [CI], 0.83 to 1.06; P=0.30). Major bleeding occurred in 2.5% of patients in the double-dose group and in 2.0% in the standard-dose group (hazard ratio, 1.24; 95% CI, 1.05 to 1.46; P=0.01). Double-dose clopidogrel was associated with a significant reduction in the secondary outcome of stent thrombosis among the 17,263 patients who underwent PCI (1.6% vs. 2.3%; hazard ratio, 0.68; 95% CI, 0.55 to 0.85; P=0.001). There was no significant difference between higher-dose and lower-dose aspirin with respect to the primary outcome (4.2% vs. 4.4%; hazard ratio, 0.97; 95% CI, 0.86 to 1.09; P=0.61) or major bleeding (2.3% vs. 2.3%; hazard ratio, 0.99; 95% CI, 0.84 to 1.17; P=0.90). CONCLUSIONS: In patients with an acute coronary syndrome who were referred for an invasive strategy, there was no significant difference between a 7-day, double-dose clopidogrel regimen and the standard-dose regimen, or between higher-dose aspirin and lower-dose aspirin, with respect to the primary outcome of cardiovascular death, myocardial infarction, or stroke. (Funded by Sanofi-Aventis and Bristol-Myers Squibb; ClinicalTrials.gov number, NCT00335452.)

Radial versus femoral access for coronary angiography and intervention in patients with acute coronary syndromes (RIVAL): a randomised, parallel group, multicentre trial.

BACKGROUND: Small trials have suggested that radial access for percutaneous coronary intervention (PCI) reduces vascular complications and bleeding compared with femoral access. We aimed to assess whether radial access was superior to femoral access in patients with acute coronary syndromes (ACS) who were undergoing coronary angiography with possible intervention. METHODS: The RadIal Vs femorAL access for coronary intervention (RIVAL) trial was a randomised, parallel group, multicentre trial. Patients with ACS were randomly assigned (1:1) by a 24 h computerised central automated voice response system to radial or femoral artery access. The primary outcome was a composite of death, myocardial infarction, stroke, or non-coronary artery bypass graft (non-CABG)-related major bleeding at 30 days. Key secondary outcomes were death, myocardial infarction, or stroke; and non-CABG-related major bleeding at 30 days. A masked central committee adjudicated the primary outcome, components of the primary outcome, and stent thrombosis. All other outcomes were as reported by the investigators. Patients and investigators were not masked to treatment allocation. Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, NCT01014273. FINDINGS: Between June 6, 2006, and Nov 3, 2010, 7021 patients were enrolled from 158 hospitals in 32 countries. 3507 patients were randomly assigned to radial access and 3514 to femoral access. The primary outcome occurred in 128 (3·7%) of 3507 patients in the radial access group compared with 139 (4·0%) of 3514 in the femoral access group (hazard ratio [HR] 0·92, 95% CI 0·72-1·17; p=0·50). Of the six prespecified subgroups, there was a significant interaction for the primary outcome with benefit for radial access in highest tertile volume radial centres (HR 0·49, 95% CI 0·28-0·87; p=0·015) and in patients with ST-segment elevation myocardial infarction (0·60, 0·38-0·94; p=0·026). The rate of death, myocardial infarction, or stroke at 30 days was 112 (3·2%) of 3507 patients in the radial group compared with 114 (3·2%) of 3514 in the femoral group (HR 0·98, 95% CI 0·76-1·28; p=0·90). The rate of non-CABG-related major bleeding at 30 days was 24 (0·7%) of 3507 patients in the radial group compared with 33 (0·9%) of 3514 patients in the femoral group (HR 0·73, 95% CI 0·43-1·23; p=0·23). At 30 days, 42 of 3507 patients in the radial group had large haematoma compared with 106 of 3514 in the femoral group (HR 0·40, 95% CI 0·28-0·57; p<0·0001). Pseudoaneurysm needing closure occurred in seven of 3507 patients in the radial group compared with 23 of 3514 in the femoral group (HR 0·30, 95% CI 0·13-0·71; p=0·006). INTERPRETATION: Radial and femoral approaches are both safe and effective for PCI. However, the lower rate of local vascular complications may be a reason to use the radial approach. FUNDING: Sanofi-Aventis, Population Health Research Institute, and Canadian Network for Trials Internationally (CANNeCTIN), an initiative of the Canadian Institutes of Health Research.

Dabigatran versus warfarin in patients with atrial fibrillation.

BACKGROUND: Warfarin reduces the risk of stroke in patients with atrial fibrillation but increases the risk of hemorrhage and is difficult to use. Dabigatran is a new oral direct thrombin inhibitor. METHODS: In this noninferiority trial, we randomly assigned 18,113 patients who had atrial fibrillation and a risk of stroke to receive, in a blinded fashion, fixed doses of dabigatran--110 mg or 150 mg twice daily--or, in an unblinded fashion, adjusted-dose warfarin. The median duration of the follow-up period was 2.0 years. The primary outcome was stroke or systemic embolism. RESULTS: Rates of the primary outcome were 1.69% per year in the warfarin group, as compared with 1.53% per year in the group that received 110 mg of dabigatran (relative risk with dabigatran, 0.91; 95% confidence interval [CI], 0.74 to 1.11; P<0.001 for noninferiority) and 1.11% per year in the group that received 150 mg of dabigatran (relative risk, 0.66; 95% CI, 0.53 to 0.82; P<0.001 for superiority). The rate of major bleeding was 3.36% per year in the warfarin group, as compared with 2.71% per year in the group receiving 110 mg of dabigatran (P=0.003) and 3.11% per year in the group receiving 150 mg of dabigatran (P=0.31). The rate of hemorrhagic stroke was 0.38% per year in the warfarin group, as compared with 0.12% per year with 110 mg of dabigatran (P<0.001) and 0.10% per year with 150 mg of dabigatran (P<0.001). The mortality rate was 4.13% per year in the warfarin group, as compared with 3.75% per year with 110 mg of dabigatran (P=0.13) and 3.64% per year with 150 mg of dabigatran (P=0.051). CONCLUSIONS: In patients with atrial fibrillation, dabigatran given at a dose of 110 mg was associated with rates of stroke and systemic embolism that were similar to those associated with warfarin, as well as lower rates of major hemorrhage. Dabigatran administered at a dose of 150 mg, as compared with warfarin, was associated with lower rates of stroke and systemic embolism but similar rates of major hemorrhage. (ClinicalTrials.gov number, NCT00262600.)

Double-dose versus standard-dose clopidogrel and high-dose versus low-dose aspirin in individuals undergoing percutaneous coronary intervention for acute coronary syndromes (CURRENT-OASIS 7): a randomised factorial trial.

BACKGROUND: Clopidogrel and aspirin are the most commonly used antiplatelet therapies for percutaneous coronary intervention (PCI). We assessed the effect of various clopidogrel and aspirin regimens in prevention of major cardiovascular events and stent thrombosis in patients undergoing PCI. METHODS: The CURRENT-OASIS 7 trial was undertaken in 597 centres in 39 countries. 25,086 individuals with acute coronary syndromes and intended early PCI were randomly assigned to double-dose (600 mg on day 1, 150 mg on days 2-7, then 75 mg daily) versus standard-dose (300 mg on day 1 then 75 mg daily) clopidogrel, and high-dose (300-325 mg daily) versus low-dose (75-100 mg daily) aspirin. Randomisation was done with a 24 h computerised central automated voice response system. The clopidogrel dose comparison was double-blind and the aspirin dose comparison was open label with blinded assessment of outcomes. This prespecified analysis is of the 17,263 individuals who underwent PCI. The primary outcome was cardiovascular death, myocardial infarction, or stroke at 30 days. Analyses were by intention to treat, adjusted for propensity to undergo PCI. This trial is registered with ClinicalTrials.gov, number NCT00335452. FINDINGS: 8560 patients were assigned to double-dose and 8703 to standard-dose clopidogrel (8558 and 8702 completed 30-day follow-up, respectively), and 8624 to high-dose and 8639 to low-dose aspirin (8622 and 8638 completed 30-day follow-up, respectively). Compared with the standard dose, double-dose clopidogrel reduced the rate of the primary outcome (330 events [3·9%] vs 392 events [4·5%]; adjusted hazard ratio 0·86, 95% CI 0·74-0·99, p=0·039) and definite stent thrombosis (58 [0·7%] vs 111 [1·3%]; 0·54 [0·39-0·74], p=0·0001). High-dose and low-dose aspirin did not differ for the primary outcome (356 [4·1%] vs 366 [4·2%]; 0·98, 0·84-1·13, p=0·76). Major bleeding was more common with double-dose than with standard-dose clopidogrel (139 [1·6%] vs 99 [1·1%]; 1·41, 1·09-1·83, p=0·009) and did not differ between high-dose and low-dose aspirin (128 [1·5%] vs 110 [1·3%]; 1·18, 0·92-1·53, p=0·20). INTERPRETATION: In patients undergoing PCI for acute coronary syndromes, a 7-day double-dose clopidogrel regimen was associated with a reduction in cardiovascular events and stent thrombosis compared with the standard dose. Efficacy and safety did not differ between high-dose and low-dose aspirin. A double-dose clopidogrel regimen can be considered for all patients with acute coronary syndromes treated with an early invasive strategy and intended early PCI. FUNDING: Sanofi-Aventis and Bristol-Myers Squibb.

Relationship between baseline haemoglobin and major bleeding complications in acute coronary syndromes.

AIMS: In patients with acute coronary syndromes (ACS), the negative impact of baseline haemoglobin levels on ischaemic events, particularly death, is well established, but the association with bleeding risk is less well studied. The aim of this study was to assess the impact of baseline haemoglobin levels on major bleeding complications. METHODS AND RESULTS: Pooled analysis of OASIS 5 and 6 data involving 32 170 patients with ACS with and without ST-segment elevation was performed. The association between baseline haemoglobin and major bleeding or ischaemic events was examined using multiple regression model. MAIN OUTCOME MEASURES: were 30-day rates of major bleeding, death, and death/myocardial infarction (MI) analysed according to baseline haemoglobin levels. Baseline haemoglobin level independently predicted the risk of overall, procedure-related, and non-procedure-related major bleedings at 30 days [odds ratio (OR) 0.94, 95% CI 0.90-0.98; OR 0.94, 95% CI 0.90-0.99; and OR 0.89, 95% CI 0.83-0.95, respectively, per 1 g/dL haemoglobin increment above 10 g/dL]. In addition, a curvilinear relationship between baseline haemoglobin levels and death at 30 days was observed with a 6% decrease in the risk for every 1 g/dL haemoglobin increment above 10 g/dL up to 15.9 g/dL (OR 0.94, 95% CI 0.90-0.98) and a 19% increase above this value (OR 1.19, 95% CI, 0.98-1.43). A similar relationship for the composite outcome of death/MI was observed. CONCLUSION: A low baseline haemoglobin level is an independent predictor of the risk of major bleeding in ACS as well as of the risk of death and death and MI. Among other predictors of bleeding risk, baseline haemoglobin should be taken into account in patients presenting with ACS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number, NCT00139815. http://clinicaltrials.gov/ct2/show/NCT00139815?term=NCT00139815&rank=1.

Association of Bicuspid aortic valve morphology and aortic root dimensions: a substudy of the aortic stenosis progression observation measuring effects of rosuvastatin (ASTRONOMER) study.

BACKGROUND: Bicuspid aortic valve (BAV) is the leading cause of aortic stenosis in patients younger than the age of 50. A classification scheme of BAVs is based upon leaflet orientation: Type I (fusion of right and left coronary cusps) and Type II (fusion of right and noncoronary cusps). The correlation between BAV leaflet orientation and aortic root pathology however remains ill defined. OBJECTIVE: The objective was to describe a potential relationship between BAV leaflet morphology and aortic root measurements in the ASTRONOMER study, a multicenter study to assess the effect of rosuvastatin on the progression of AS. METHODS: BAV morphology was classified as Type I or Type II orientation based on the parasternal short-axis view. Echo measurements including left ventricular and aortic root dimensions were obtained. RESULTS: The study population included 89 patients (56 +/- 11 years; 44 males). There were 63 patients with Type I and 26 patients with Type II BAV. Baseline demographics, hemodynamics, and left heart dimensions were similar between both groups. Patients with Type I BAV had larger aortic annulus and ascending root dimensions compared to those patients with Type II BAV (P < 0.05). CONCLUSION: In patients with mild to moderate aortic stenosis due to a BAV, the presence of Type I valve orientation was associated with significantly greater aortic root parameters compared to Type II valve orientation.

Improving clinical outcomes by reducing bleeding in patients with non-ST-elevation acute coronary syndromes.

AIMS: Bleeding in patients with coronary artery disease has been linked with adverse outcomes. We examined the incidence and outcomes after bleeding in 20 078 patients with acute coronary syndromes (ACS) enrolled in the OASIS-5 trial who were treated with fondaparinux or the low-molecular weight heparin, enoxaparin. METHODS AND RESULTS: Nine hundred and ninety (4.9%) patients developed major bleeding and 423 (2.1%) developed minor bleeding. Fondaparinux compared with enoxaparin reduced fatal bleeding [0.07 vs. 0.22%, relative risk (RR) 0.30, 95% CI: 0.13-0.71], non-fatal major bleeding (2.2 vs. 4.2%, RR 0.52, 95% CI: 0.44-0.61), minor bleeding (1.1 vs. 3.2%, RR 0.34, 95% CI: 0.27-0.42), and need for transfusion (1.8 vs. 3.1%, RR 0.56, 95% CI: 0.47-0.61) during the first 9 days. One of every six deaths during the first 30 days occurred in patients who experienced bleeding. Cox proportional hazards model revealed that major bleeding was associated with about a four-fold increased hazard of death, myocardial infarction, or stroke during the first 30 days and about a three-fold increased hazard during 180 days of follow up. CONCLUSION: Bleeding in patients with ACS is a powerful determinant of fatal and non-fatal outcomes. Reducing the risk of bleeding using a safer anticoagulant strategy during the first 9 days is associated with substantial reductions in morbidity and mortality.

Fondaparinux compared to enoxaparin in patients with acute coronary syndromes without ST-segment elevation: outcomes and treatment effect across different levels of risk.

BACKGROUND: The OASIS-5 (Organization to Assess Strategies in Ischemic Syndromes-5) trial demonstrated that fondaparinux was noninferior to enoxaparin while reducing the risk of bleeding by 50%. The objectives of our study were to assess the effects of fondaparinux compared to enoxaparin in patients stratified by their Global Registry of Acute Coronary Events (GRACE) score and to examine the ability of the GRACE score to predict bleeding in patients with acute coronary syndromes (ACS). METHODS: We analyzed efficacy and safety according to the GRACE admission risk score. RESULTS: The impact of fondaparinux versus enoxaparin on the primary outcome of death, myocardial infarction, and refractory ischemia at 180 days was similar in the low-, intermediate-, and high-risk groups: 7.0% versus 7.7% (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.75-1.08), 10.2% versus 11.3% (HR 0.89, 95% CI 0.77-1.03), and 20.1% versus 21.1% (HR 0.95, 95% CI 0.85-1.06). Major bleeding rates were higher with increasing GRACE risk scores: 2.2%, 3.2%, and 4.1% in the low, intermediate, and high-risk groups. Six-month mortality was 2.2%, 4.2%, and 12.3% in the 3 groups. The risk of major bleeding was substantially lower with fondaparinux in all groups: 1.6% versus 2.9% (HR 0.55, 95% CI 0.39-0.77), 2.2% versus 4.1% (HR 0.53, 95% CI 0.40-0.70), 2.8% versus 5.5% (HR 0.50, 95% CI 0.38-0.64). CONCLUSION: The GRACE score predicted both bleeding and mortality in patients with ACS. The efficacy and safety of fondaparinux were consistent in all risk groups supporting its use in a broad range of ACS patients.

Association of mitral annular calcification and aortic valve morphology: a substudy of the aortic stenosis progression observation measuring effects of rosuvastatin (ASTRONOMER) study.

AIMS: Mitral annular calcification (MAC) is characterized by calcium and lipid deposition in the annular fibrosa of the mitral valve. Although individuals with MAC are at increased risk of cardiovascular events, little is known about the significance of this finding in patients with concurrent aortic stenosis (AS). The aim of this study was to describe the association of baseline MAC and aortic valve morphology in asymptomatic patients enrolled in the ASTRONOMER study, a multicentre study to assess the effect of Rosuvastatin on the progression of AS. METHODS AND RESULTS: At baseline, transthoracic echocardiography was performed with two-dimensional and Doppler imaging following a standardized protocol. Echo measurements including left ventricular (LV) dimensions and aortic root dimensions were obtained according to the ASE recommendations. MAC was identified by bright echoes at the base of the mitral leaflets or annulus on 2D imaging, and aortic valve calcification by visualization of bright echoes on the aortic valve leaflets. The degree of calcification was semi-quantitated from absent to severe. The study population included 219 patients (57 +/- 14 years; 129 males), divided into two pre-specified categories; bicuspid (n = 133) and tricuspid (n = 86) aortic valves. Baseline LV dimensions, aortic valve haemodynamics, and cholesterol profiles were similar between the two groups at baseline. Individuals with tricuspid aortic valves were older, more hypertensive, with higher degrees of MAC and AV calcification (P < 0.001). The higher degree of MAC persisted in patients with tricuspid AV after adjustment for age and systolic blood pressure (P = 0.004). CONCLUSION: In patients with asymptomatic mild to moderate AS, MAC is more prevalent in those individuals with tricuspid AV, independent of age, and systolic blood pressure. Whether the degree of MAC may be a surrogate for atherosclerosis, and predict the subset of patients who will respond to statin therapy in preventing the progression of AS, remains to be determined.

The importance of echocardiography in physicians' support of endocarditis prophylaxis.

BACKGROUND: Guidelines advocate for antimicrobial prophylaxis for prevention of bacterial endocarditis. Our objective was to explore physicians' perspectives regarding the importance of echocardiography in the evaluation and management of endocarditis prophylaxis. METHODS: A total of 260 cardiologists and 300 family physicians practicing in Ontario, Canada, were surveyed. Our main outcome measures were physician ratings of the importance of a murmur, echocardiogram findings, echocardiogram comments, comorbid conditions, guidelines, patient insistence, and medicolegal concerns on the decision to recommend prophylaxis, as well as the degree of echocardiographically detected mitral valve abnormality required prior to recommending prophylaxis. RESULTS: The survey response rate was 62%. Echocardiographic findings were rated by 81% of physicians as the most important factor influencing the decision to provide prophylaxis. Conversely, only 27% of physicians placed similar importance on clinical findings. Family physicians relied more heavily on echocardiographic than on clinical findings when supporting endocarditis prophylaxis recommendations. On average, prophylaxis was recommended for moderate to severe regurgitation in a normal valve and mild regurgitation in a mildly abnormal structural mitral valve. Physicians who reported greater reliance on echocardiographic findings advocated for prophylaxis at lower echocardiographic thresholds than did those who reported greater reliance on murmur detection for endocarditis prophylaxis decisions. CONCLUSIONS: Physicians strongly support the use of echocardiography in endocarditis prophylaxis decision making. However, the importance of echocardiography relative to other factors varies across physician specialties. Further studies must evaluate the role of echocardiography in the assessment and management of antimicrobial endocarditis prophylaxis to assist in the development of clear clinical guidelines.

Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant.

BACKGROUND: Although small valve size and patient-prosthesis mismatch are both considered to decrease long-term survival, little direct evidence exists to support this hypothesis. METHODS: To assess the prevalence of patient-prosthesis mismatch and the influence of small valve size on survival, we prospectively studied 1,129 consecutive patients undergoing aortic valve replacement between 1990 and 2000. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography postoperatively (3 months to 10 years). Abnormal postoperative gradients were defined as those patients with mean or peak gradient above the 90th percentile (mean gradient > or = 21 or peak gradient > or = 38 mm Hg). Patient-prosthesis mismatch was defined as those patients with indexed effective orifice area below the 10th percentile (< 0.60 cm2/m2). RESULTS: A multivariable analysis identified internal diameter of the implanted valve as the only independent predictor of abnormal gradients postoperatively. However, there was no significant difference in actuarial survival between normal and abnormal gradient groups (7 years: 91.2% +/- 1.5% versus 95.0% +/- 2.2%; p = 0.48). Freedom from New York Heart Association class III or IV (7 years: 74.5% +/- 3.1% versus 74.6% +/- 6.2%; p = 0.66) and left ventricular mass index were not different between normal and abnormal gradient groups. Patients with and without patient-prosthesis mismatch were similar with respect to postoperative left ventricular mass index, 7-year survival (95.1% +/- 1.3% versus 94.7% +/- 3.0%; p = 0.54), and 7-year freedom from New York Heart Association class III or IV (79.3% +/- 6.6% versus 74.5% +/- 2.5%; p = 0.40). In patients with patient-prosthesis mismatch and abnormal gradients, the majority had prosthesis dysfunction owing to degeneration. CONCLUSIONS: Severe patient-prosthesis mismatch is rare after aortic valve replacement. Patient-prosthesis mismatch, abnormal gradient, and the size of valve implanted do not influence left ventricular mass index or intermediate-term survival.

Are stentless valves hemodynamically superior to stented valves? A prospective randomized trial.

BACKGROUND: Although stentless aortic bioprostheses are believed to offer improved outcomes, hemodynamic benefits remain unsubstantiated. METHODS: Fifty-three patients were randomized to receive the stented C-E pericardial valve (CE) and 46 patients the Toronto Stentless Porcine valve (SPV). Annuli were sized for the optimal insertion of both valve types, such that surgeons were required to commit to specific valve sizes before randomization. Echocardiographic measurements and functional status (Duke Activity Status Index) were assessed at 3 and 12 months postoperatively. RESULTS: Although cardiopulmonary bypass times (CE: 118.6+/-36.3 minutes; SPV: 148.5+/-30.9 minutes; p = 0.0001) and aortic cross-clamp times (CE: 95.4+/-28.6 minutes; SPV: 123.6+/-24.1 minutes; p = 0.0001) were significantly prolonged in the SPV group, perioperative morbidity and mortality was similar between groups. Neither valve offered a superior internal diameter for any given annular diameter (mean decrease in left ventricular outflow tract diameter after valvular implantation: SPV: 3.4+/-1.11 mm versus CE: 3.7+/-1.33 mm; p = 0.25). Although labeled mean valve size was significantly larger in the SPV group, the actual mean valve size based on internal valvular diameter was no different between groups (CE: 21.9+/-2.0 mm; SPV: 22.3+/-2.0 mm; p = 0.286). Although effective orifice areas increased, and mean and peak transvalvular gradients decreased in both groups over time, no differences were demonstrated between groups at 12 months. Similarly, although significant regression of left ventricular mass was accomplished in both groups over time, no differences were demonstrated between groups. Finally, Duke Activity Status Index scores of functional status improved in both groups over time; however, no differences were noted between groups at 12 months postoperatively. CONCLUSIONS: Although offering excellent outcomes, stentless valves did not demonstrate superior hemodynamic indices in comparison to stented valves up to 12 months after implantation.

Differential effects of once-daily antihypertensive drugs on blood pressure, left ventricular mass and sympathetic activity: Nifedipine-GITS versus felodipine-ER versus enalapril.

BACKGROUND: Recent meta-analyses suggest that once-daily dihydropyridines and angiotensin-converting enzyme inhibitors cause similar decreases in left ventricular (LV) mass for comparable decreases in blood pressure (BP). However, some dihydropyridines, such as felodipine-extended release (ER), still increase sympathetic activity and may, therefore, be less effective in decreasing LV mass. OBJECTIVES: To evaluate the effects of long term antihypertensive treatment with nifedipine-gastrointestinal therapeutic system (GITS) and felodipine-ER compared with enalapril on LV mass relative to the extent of BP control (assessed by 24 h ambulatory BP monitoring) and sympathetic activity (assessed by plasma catecholamine concentrations). PATIENTS AND METHODS: Enalapril was started at 10 mg/day, felodipine-ER at 5 mg/day and nifedipine-GITS at 30 mg/day, all once daily. Doses were increased to 20 mg/day, 10 mg/day or 60 mg/day, respectively, if the office BP remained 160/90 mmHg or greater at the end of the dosing interval. Evaluable echocardiograms were obtained for 116 patients at the end of the study (30 weeks of treatment). RESULTS: On 24 h ambulatory BP monitoring, nifedipine-GITS caused a consistent decrease in BP throughout the 24 h dosing interval, whereas felodipine-ER caused a more marked fall in BP during the day, and enalapril's effects diminished during the night and had disappeared by the morning. Only felodipine-ER significantly increased supine and standing plasma noradrenaline by more than 50% similarly after six, 18, and 30 weeks of treatment. In BP responders (decrease in systolic BP 10 mmHg or greater), enalapril and nifedipine-GITS caused clear decreases in LV mass by 12 to 16 g/m2, whereas felodipine-ER was less effective (decrease by only 6 g/m2, P<0.01 versus enalapril). CONCLUSIONS: Once-daily dihydropyridines should not be regarded as one homogeneous class and, compared with felodipine-ER, nifedipine-GITS exhibits a better profile regarding 24 h BP control, sympathetic activation and regression of LV mass.

Apixaban versus aspirin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a predefined subgroup analysis from AVERROES, a randomised trial.

BACKGROUND: In the AVERROES study, apixaban, a novel factor Xa inhibitor, reduced the risk of stroke or systemic embolism in patients with atrial fibrillation who were at high risk of stroke but unsuitable for vitamin K antagonist therapy. We aimed to investigate whether the subgroup of patients with previous stroke or transient ischaemic attack (TIA) would show a greater benefit from apixaban compared with aspirin than would patients without previous cerebrovascular events. METHODS: In AVERROES, 5599 patients (mean age 70 years) with atrial fibrillation who were at increased risk of stroke and unsuitable for vitamin K antagonist therapy were randomly assigned to receive apixaban (5 mg twice daily) or aspirin (81-324 mg per day). The mean follow-up was 1·1 years. The primary efficacy outcome was stroke or systemic embolism; the primary safety outcome was major bleeding. Patients and investigators were masked to study treatment. In this prespecified subgroup analysis, we used Kaplan-Meier estimates of 1-year event risk and Cox proportional hazards regression models to compare the effects of apixaban in patients with and without previous stroke or TIA. AVERROES is registered at ClinicalTrials.gov, number NCT00496769. FINDINGS: In patients with previous stroke or TIA, ten events of stroke or systemic embolism occurred in the apixaban group (n=390, cumulative hazard 2·39% per year) compared with 33 in the aspirin group (n=374, 9·16% per year; hazard ratio [HR] 0·29, 95% CI 0·15-0·60). In those without previous stroke or TIA, 41 events occurred in the apixaban group (n=2417, 1·68% per year) compared with 80 in the aspirin group (n=2415, 3·06% per year; HR 0·51, 95% CI 0·35-0·74). The p value for interaction of the effects of aspirin and apixaban with previous cerebrovascular events was 0·17. Major bleeding was more frequent in patients with history of stroke or TIA than in patients without (HR 2·88, 95% CI 1·77-4·55) but risk of this event did not differ between treatment groups. INTERPRETATION: In patients with atrial fibrillation, apixaban is similarly effective whether or not patients have had a previous stroke or TIA. Given that those with previous stroke or TIA have a higher risk of stroke, the absolute benefits might be greater in these patients. FUNDING: Bristol-Myers Squibb and Pfizer.

Are stentless valves hemodynamically superior to stented valves? Long-term follow-up of a randomized trial comparing Carpentier-Edwards pericardial valve with the Toronto Stentless Porcine Valve.

OBJECTIVE: The benefit of stentless valves remains in question. In 1999, a randomized trial comparing stentless and stented valves was unable to demonstrate any hemodynamic or clinical benefits at 1 year after implantation. This study reviews long-term outcomes of patients randomized in the aforementioned trial. METHODS: Between 1996 and 1999, 99 patients undergoing aortic valve replacement were randomized to receive either a stented Carpentier-Edwards pericardial valve (CE) (Edwards Lifesciences, Irvine, Calif) or a Toronto Stentless Porcine Valve (SPV) (St Jude Medical, Minneapolis, Minn). Among these, 38 patients were available for late echocardiographic follow-up (CE, n = 17; SPV, n = 21). Echocardiographic analysis was undertaken both at rest and with dobutamine stress, and functional status (Duke Activity Status Index) was compared at a mean of 9.3 years postoperatively (range, 7.5-11.1 years). Clinical follow-up was 82% complete at a mean of 10.3 years postoperatively (range, 7.5-12.2 years). RESULTS: Preoperative characteristics were similar between groups. Effective orifice areas increased in both groups over time. Although there were no differences in effective orifice areas at 1 year, at 9 years, effective orifice areas were significantly greater in the SPV group (CE, 1.49 +/- 0.59 cm(2); SPV, 2.00 +/- 0.53 cm(2); P = .011). Similarly, mean and peak gradients decreased in both groups over time; however, at 9 years, gradients were lower in the SPV group (mean: CE, 10.8 +/- 3.8 mm Hg; SPV, 7.8 +/- 4.8 mm Hg; P = .011; peak: CE, 20.4 +/- 6.5 mm Hg; SPV, 14.6 +/- 7.1 mm Hg; P = .022). Such differences were magnified with dobutamine stress (mean: CE, 22.7 +/- 6.1 mm Hg; SPV, 15.3 +/- 8.4 mm Hg; P = .008; peak: CE, 48.1 +/- 11.8 mm Hg; SPV, 30.8 +/- 17.7 mm Hg; P = .001). Ventricular mass regression occurred in both groups; however, no differences were demonstrated between groups either on echocardiographic, magnetic resonance imaging, or biochemical (plasma B-type [brain] natriuretic peptide) assessment (P = .74). Similarly, Duke Activity Status Index scores of functional status improved in both groups over time; however, no differences were noted between groups (CE, 27.5 +/- 19.1; SPV, 19.9 +/- 12.0; P = .69). Freedom from reoperation at 12 years was 92% +/- 5% in patients with CEs and 75% +/- 5% in patients with SPVs (P = .65). Freedom from valve-related morbidity at 12 years was 82% +/- 7% in patients with CEs and 55% +/- 7% in patients with SPVs (P = .05). Finally, 12-year actuarial survival was 35% +/- 7% in patients with CEs and 52% +/- 7% in patients with SPVs (P = .37). CONCLUSION: Although offering improved hemodynamic outcomes, the SPV did not afford superior mass regression or improved clinical outcomes up to 12 years after implantation.

Efficacy and safety of fondaparinux versus enoxaparin in patients with acute coronary syndromes treated with glycoprotein IIb/IIIa inhibitors or thienopyridines: results from the OASIS 5 (Fifth Organization to Assess Strategies in Ischemic Syndromes) trial.

OBJECTIVES: This study sought to evaluate the relative safety and efficacy of fondaparinux and enoxaparin in patients with acute coronary syndromes (ACS) treated with glycoprotein (GP) IIb/IIIa inhibitors or thienopyridines. BACKGROUND: The OASIS 5 (Fifth Organization to Assess Strategies in Ischemic Syndromes) trial showed that fondaparinux reduced major bleeding by 50% compared with enoxaparin while preserving similar efficacy. Whether this benefit is consistent in the presence or absence of concurrent antiplatelet therapy with clopidogrel and GP IIb/IIIa inhibitors is unknown. METHODS: Patients with ACS (n = 20,078) were randomized as a part of the OASIS 5 trial to receive either fondaparinux or enoxaparin. The use of GP IIb/IIIa inhibitors or thienopyridines was at the discretion of the treating physician. A Cox proportional hazard model was used to compare outcomes. RESULTS: Of the 20,078 patients randomized, 3,630 patients received GP IIb/IIIa and 13,531 received thienopyridines. There was a 40% reduction in major bleeding with fondaparinux compared with enoxaparin in those treated with GP IIb/IIIa (5.2% vs. 8.3%, hazard ratio [HR]: 0.61, p < 0.001). A similar reduction was found in those treated with thienopyridines (3.4% vs. 5.4%, HR: 0.62, p < 0.001). Ischemic events were similar between the groups, resulting in a superior net clinical outcome (death, myocardial infarction, refractory ischemia, or major bleeding) favoring fondaparinux (GP IIb/IIIa subgroup 14.8% vs. 18.9%, HR: 0.77, p = 0.001 and thienopyridines subgroup 11.0% vs. 13.2%, HR: 0.82, p < 0.001). CONCLUSIONS: In patients receiving GP IIb/IIIa inhibitors or thienopyridines, fondaparinux reduces major bleeding and improves net clinical outcome compared with enoxaparin.

Clinical usefulness of tissue Doppler imaging in patients with mild to moderate aortic stenosis: a substudy of the aortic stenosis progression observation measuring effects of rosuvastatin study.

OBJECTIVE: Although impaired diastolic function is common in aortic stenosis (AS), little is known about the clinical usefulness of tissue Doppler imaging (TDI) to detect diastolic dysfunction in patients with mild to moderate AS. The objective was to describe both conventional and TDI measurements of diastolic function in asymptomatic patients enrolled in the Aortic Stenosis Progression Observation Measuring Effects of Rosuvastatin study, a multicenter study to assess the effect of rosuvastatin on the progression of AS. METHODS: Baseline echocardiography measurements, including left ventricular interventricular septal thickness, posterior wall thickness, cavity dimensions, and ejection fraction were obtained. Conventional Doppler indices, including peak early (E) and late (A) transmitral velocities, E/A ratio, and E-wave deceleration time, were measured from spectral Doppler. Tissue Doppler measurements, including early (E') and late (A') velocities of the lateral annulus, were determined, and E/E' was calculated. RESULTS: The study population included 172 patients (aged 57 +/- 13 years; 73 were female) divided into three categories of AS severity on the basis of peak velocity at baseline (group I: 2.5-3.0 m/s; group II: 3.1-3.5 m/s; group III; 3.6-4.0 m/s). Baseline hemodynamics, left ventricular dimensions, and conventional diastolic functional parameters were similar among all 3 groups. In patients with greater severity of AS, the lateral E' was lower and the E/E' (as an estimate of increased left ventricular end-diastolic pressure) was higher (P <.05). CONCLUSION: In patients with mild to moderate asymptomatic AS, TDI measures of diastolic function are abnormal and related to the severity of AS. These findings may help to predict the future development of symptoms in this population.

Determinants of incomplete left ventricular mass regression following aortic valve replacement for aortic stenosis.

OBJECTIVE: Incomplete regression of left ventricular hypertrophy (Abn-LVMI) following AVR for aortic stenosis (AS) may decrease long-term survival. In this prospective study, we identified the predictors of Abn-LVMI. METHODS: Between 1990 and 2000, 529 patients undergoing AVR for AS had clinical and hemodynamic data collected prospectively. Preoperative and annual postoperative transthoracic echos were employed to assess left ventricular mass index (LVMI) and hemodynamics. Abn-LVMI was defined as the 75th percentile of the lowest postoperative LVMI (>128 mg/m2, n = 133). All other patients were included in the normal regression group (N-LVMI). Univariate and multivariable logistic regression analyses were used to determine the predictors of Abn-LVMI. RESULTS: Preoperative hypertension, diabetes, coronary disease, valve size, mean postoperative gradients, effective orifice area, and patient-prosthesis mismatch (PPM, indexed EOA <0.60 cm2/m2) did not predict Abn-LVMI. By logistic regression the most important positive predictor of Abn-LVMI was the extent of preoperative LVMI, with an odds ratio of 37.5 (p < 0.0001). Survival (93.4 +/- 1.8% vs 94.8 +/- 2.3%, p = 0.90) and freedom from NYHA III-IV (75.0 +/- 3.7% vs 76.6 +/- 5.3%, p = 0.60) were similar for both groups at 7 years. CONCLUSIONS: Measures of valve hemodynamics were not important predictors of incomplete regression of hypertrophy. The extent of preoperative hypertrophy was the most important predictor, suggesting that earlier surgical intervention may reduce the extent of hypertrophy postoperatively. Furthermore, the significance of LV hypertrophy to long-term survival must be reassessed, in the absence of scientific evidence.