Reda Ibrahim

Percutaneous Closure of Patent Foramen Ovale in Cryptogenic Embolism

BACKGROUND The options for secondary prevention of cryptogenic embolism in patients with patent foramen ovale are administration of antithrombotic medications or percutaneous closure of the patent foramen ovale. We investigated whether closure is superior to medical therapy. METHODS We performed a multicenter, superiority trial in 29 centers in Europe, Canada, Brazil, and Australia in which the assessors of end points were unaware of the study-group assignments. Patients with a patent foramen ovale and ischemic stroke, transient ischemic attack (TIA), or a peripheral thromboembolic event were randomly assigned to undergo closure of the patent foramen ovale with the Amplatzer PFO Occluder or to receive medical therapy. The primary end point was a composite of death, nonfatal stroke, TIA, or peripheral embolism. Analysis was performed on data for the intention-to-treat population. RESULTS The mean duration of follow-up was 4.1 years in the closure group and 4.0 years in the medical-therapy group. The primary end point occurred in 7 of the 204 patients (3.4%) in the closure group and in 11 of the 210 patients (5.2%) in the medical-therapy group (hazard ratio for closure vs. medical therapy, 0.63; 95% confidence interval [CI], 0.24 to 1.62; P=0.34). Nonfatal stroke occurred in 1 patient (0.5%) in the closure group and 5 patients (2.4%) in the medical-therapy group (hazard ratio, 0.20; 95% CI, 0.02 to 1.72; P=0.14), and TIA occurred in 5 patients (2.5%) and 7 patients (3.3%), respectively (hazard ratio, 0.71; 95% CI, 0.23 to 2.24; P=0.56). CONCLUSIONS Closure of a patent foramen ovale for secondary prevention of cryptogenic embolism did not result in a significant reduction in the risk of recurrent embolic events or death as compared with medical therapy. (Funded by St. Jude Medical; ClinicalTrials.gov number, NCT00166257.).

Effects of the Acyl Coenzyme A:Cholesterol Acyltransferase Inhibitor Avasimibe on Human Atherosclerotic Lesions

Background—Inhibition of the acyl coenzyme A:cholesterol acyltransferase (ACAT) enzyme may prevent excess accumulation of cholesteryl esters in macrophages. The ACAT inhibitor avasimibe was shown to reduce experimental atherosclerosis. This study was designed to investigate the effects of avasimibe on human coronary atherosclerosis. Methods and Results—This randomized, double-blind, placebo-controlled trial assessed the effects of avasimibe at dosages of 50, 250, and 750 mg QD on the progression of coronary atherosclerosis as assessed by intravascular ultrasound (IVUS). All patients received background lipid-lowering therapy if necessary to reach a target baseline LDL level <125 mg/dL (3.2 mmol/L). IVUS and coronary angiography were performed at baseline and repeated after up to 24 months of treatment. Approximately equal percentages of patients across groups received concurrent statin therapy (87% to 89%). The mean total plaque volume at baseline was ≈200 mm3, and the least squares mean change at end of treatment was 0.7 mm3 for placebo and 7.7, 4.1, and 4.8 mm3 for the avasimibe 50, 250, and 750 mg groups, respectively (adjusted P=0.17 [unadjusted P=0.057], 0.37, and 0.37, respectively). Percent atheroma volume increased by 0.4% with placebo and by 0.7%, 0.8%, and 1.0% in the respective avasimibe groups (P=NS). LDL cholesterol increased during the study by 1.7% with placebo but by 7.8%, 9.1%, and 10.9% in the respective avasimibe groups (P<0.05 in all groups). Conclusions—Avasimibe did not favorably alter coronary atherosclerosis as assessed by IVUS. This ACAT inhibitor also caused a mild increase in LDL cholesterol.

Left atrial appendage occlusion for stroke prevention in atrial fibrillation: multicentre experience with the AMPLATZER Cardiac Plug.

AIMS To investigate the safety, feasibility, and efficacy of left atrial appendage occlusion (LAAO) with the AMPLATZER Cardiac Plug (ACP) for stroke prevention in patients with atrial fibrillation (AF). METHODS AND RESULTS Data from consecutive patients treated in 22 centres were collected. A total of 1,047 patients were included in the study. Procedural success was 97.3%. There were 52 (4.97%) periprocedural major adverse events. Follow-up was complete in 1,001/1,019 (98.2%) of successfully implanted patients (average 13 months, total 1,349 patient-years). One-year all-cause mortality was 4.2%. No death at follow-up was reported as device-related. There were nine strokes (0.9%) and nine transient ischaemic attacks (0.9%) during follow-up. The annual rate of systemic thromboembolism was 2.3% (31/1,349 patient-years), which is a 59% risk reduction. There were 15 major bleedings (1.5%) during follow-up. The annual rate of major bleeding was 2.1% (28/1,349 patient-years), which is a 61% risk reduction. Patients with single LAAO on aspirin monotherapy or no therapy and longer follow-up had fewer cerebral and fewer bleeding events. CONCLUSIONS In this multicentre study, LAAO with the ACP showed high procedural success and a favourable outcome for the prevention of AF-related thromboembolism. Modification in antithrombotic therapy after LAAO may result in reduction of bleeding events.

Percutaneous Left Atrial Appendage Closure With the AMPLATZER Cardiac Plug Device in Patients With Nonvalvular Atrial Fibrillation and Contraindications to Anticoagulation Therapy

OBJECTIVES The aim of this study was to evaluate the results associated with left atrial appendage closure (LAAC) with the AMPLATZER Cardiac Plug (ACP) (St. Jude Medical, Minneapolis, Minnesota) in patients with nonvalvular atrial fibrillation and absolute contraindications to anticoagulation therapy. BACKGROUND Few data exist on the late outcomes after LAAC in patients with absolute contraindications to warfarin. METHODS A total of 52 patients with nonvalvular atrial fibrillation underwent LAAC with the ACP device in 7 Canadian centers. Most patients received short-term (1 to 3 months) dual-antiplatelet therapy after the procedure and single-antiplatelet therapy thereafter. A transesophageal echocardiography was performed in 74% of patients at the 6-month follow-up. No patient was lost to follow-up (≥ 12 months in all patients). RESULTS The mean age and median (interquartile range) CHADS2 score were 74 ± 8 years and 3 (2 to 4), respectively. The procedure was successful in 98.1% of the patients, and the main complications were device embolization (1.9%) and pericardial effusion (1.9%), with no cases of periprocedural stroke. At a mean follow-up of 20 ± 5 months, the rates of death, stroke, systemic embolism, pericardial effusion, and major bleeding were 5.8%, 1.9%, 0%, 1.9%, and 1.9%, respectively. The presence of mild peridevice leak was observed in 16.2% of patients at the 6-month follow-up as evaluated by transesophageal echocardiography. There were no cases of device thrombosis. CONCLUSIONS In patients with nonvalvular atrial fibrillation at high risk of cardioembolic events and absolute contraindications to anticoagulation, LAAC using the ACP device followed by dual-/single-antiplatelet therapy was associated with a low rate of embolic and bleeding events after a mean follow-up of 20 months. No cases of severe residual leak or device thrombosis were observed at the 6-month follow-up.

Treatment With 5-Lipoxygenase Inhibitor VIA-2291 (Atreleuton) in Patients With Recent Acute Coronary Syndrome

Background—Production of leukotrienes by 5-lipoxygenase (5-LO) has been linked to unstable atherosclerotic plaques and cardiovascular events. VIA-2291 is a potent 5-LO inhibitor. Methods and Results—In a double-blinded study, 191 patients were randomly assigned 3 weeks after an acute coronary syndrome to receive 25, 50, or 100 mg VIA-2291 or placebo daily for 12 weeks. The primary study end point, whole blood stimulated leukotriene LTB4 at trough drug level, was reduced in all VIA-2291 groups (P<0.0001) in a dose-dependent fashion, with approximately 80% inhibition in >90% of patients in the 100-mg group. A significant reduction of urine leukotriene LTE4 was obtained in all dose groups. No serious adverse events were considered related to study drug. A subset of 93 patients who had undergone a 64-slice coronary CT examination at baseline continued on study medication for a total of 24 weeks and underwent a repeat scan. Five of these patients withdrew or were noncompliant and 28 had nonevaluable scans. Among the 60 remaining patients, new coronary plaques were observed in 5 of 18 (27.8%) placebo-treated patients and in 2 of 42 (4.8%) VIA-2291–treated patients (P=0.01). A reduction in noncalcified plaque volume at 24 weeks versus placebo was observed in VIA-2291–treated groups in the 34 of these 60 patients in whom this end point was analyzable (P<0.01). Conclusions—VIA-2291 reduces leukotriene production at 12 weeks after an acute coronary syndrome. Preliminary data from the CT substudy suggest that such a reduction in leukotriene production may influence atherosclerosis; however, this requires confirmation in a larger study. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00358826.

Transcatheter Aortic Valve Implantation: A Canadian Cardiovascular Society Position Statement

Patients with severe symptomatic aortic stenosis have a poor prognosis with medical management alone, and balloon aortic valvuloplasty has failed to provide durable clinical benefit. Open surgical replacement of the aortic valve can improve symptoms and survival. Recently, transcatheter aortic valve implantation (TAVI) has been demonstrated to improve survival, quality of life, and functional status in nonoperable patients and to be a viable option for patients in whom the risk of open surgical morbidity or mortality is high. This Canadian Cardiovascular Society position statement represents the consensus of a representative group of cardiologists and cardiac surgeons as to the current, but evolving, role of this less-invasive new therapy. Specific recommendations are provided for selection of patients for TAVI vs surgical aortic valve replacement for native valves and for bioprostheses, approaches to patient evaluation for TAVI, appropriate constitution of multidisciplinary teams involved in performing TAVI, essential facilities that are needed to perform TAVI safely and effectively, and training/qualifications for TAVI operators. Cost considerations, complication rates, and the quality of the available evidence are also discussed. It is hoped that this consensus document will prove to be a useful resource for health professionals, institutions, departments, and decision-making bodies dealing with this important and rapidly evolving therapy.

Comparison of Intravascular Ultrasound and Quantitative Coronary Angiography for the Assessment of Coronary Artery Disease Progression

Background— The relative merits of quantitative coronary analysis (QCA) and intravascular ultrasound (IVUS) for the assessment of progression/regression in coronary artery disease are uncertain. To explore this subject further, we analyzed the angiographic and IVUS data derived from a contemporary clinical trial population. Methods and Results— We investigated the relationships between QCA and IVUS at single time points (n=525) and also for the changes over time (n=432). QCA and IVUS data underwent central laboratory analyses. Statistically significant correlations were observed between the QCA coronary artery score and the IVUS-derived lumen volume (r=0.65, P<0.0001) and total vessel volume (r=0.55, P<0.0001) and between the QCA cumulative coronary stenosis score and percent atheroma volume on IVUS (r=0.32, P<0.0001) at baseline for matched segments. A similar pattern of correlations was observed for global (all segments) QCA-derived and single-vessel IVUS-derived data. There were statistically significant but weak correlations between the changes over time in lumen dimensions on QCA and IVUS (P=0.005) and between the change in cumulative coronary stenosis score on QCA and percent atheroma volume on IVUS (r=0.14, P=0.01). Nevertheless, patients with and without angiographic progression had changes in plaque volume on IVUS of 9.13 and 0.20 mm3, respectively (P=0.028). Conclusions— QCA- and IVUS-derived measures of lumen dimensions are correlated at single time points and for changes over time. Although the change in percent atheroma volume is only weakly correlated with QCA changes as continuous variables, disease progression on QCA is associated with significant increases in plaque volume on IVUS compared with no angiographic progression.

Postinfarction Ventricular Septal Defects: Towards a New Treatment Algorithm?

BACKGROUND We reviewed our experience at the Montreal Heart Institute with early surgical and percutaneous closure of postinfarction ventricular septal defects (VSD). METHODS Between May 1995 and November 2007, 51 patients with postinfarction VSD were treated. Thirty-nine patients underwent operations, and 12 were treated with percutaneous closure of the VSD. RESULTS Half of the patients were in systemic shock, and 88% were supported with an intraaortic balloon pump before the procedure. Before the procedure, 14% of patients underwent primary percutaneous transluminal coronary angioplasty. The mean left ventricular ejection fraction was 0.44 +/- 0.11, and mean Qp/Qs was 2.3 +/- 1. Time from acute myocardial infarction to VSD diagnosis was 5.4 +/- 5.1 days, and the mean delay from VSD diagnosis to treatment was 4.0 +/- 4.0 days. A moderate to large residual VSD was present in 10% of patients after correction. Early overall mortality was 33%. Residual VSD, time from myocardial infarction to VSD diagnosis, and time from VSD diagnosis to treatment were the strongest predictor of mortality. Twelve patients were treated with a percutaneous occluder device, and the hospital or 30-day mortality in this group was 42%. CONCLUSION Small or medium VSDs can be treated definitively with a ventricular septal occluder or initially to stabilize patients and allow myocardial fibrosis, thus facilitating delayed subsequent surgical correction.

Pharmacogenomic Determinants of the Cardiovascular Effects of Dalcetrapib

Background—Dalcetrapib did not improve clinical outcomes, despite increasing high-density lipoprotein cholesterol by 30%. These results differ from other evidence supporting high-density lipoprotein as a therapeutic target. Responses to dalcetrapib may vary according to patients’ genetic profile. Methods and Results—We conducted a pharmacogenomic evaluation using a genome-wide approach in the dal-OUTCOMES study (discovery cohort, n=5749) and a targeted genotyping panel in the dal-PLAQUE-2 imaging trial (support cohort, n=386). The primary endpoint for the discovery cohort was a composite of cardiovascular events. The change from baseline in carotid intima-media thickness on ultrasonography at 6 and 12 months was evaluated as supporting evidence. A single-nucleotide polymorphism was found to be associated with cardiovascular events in the dalcetrapib arm, identifying the ADCY9 gene on chromosome 16 (rs1967309; P=2.41×10–8), with 8 polymorphisms providing P<10–6 in this gene. Considering patients with genotype AA at rs1967309, there was a 39% reduction in the composite cardiovascular endpoint with dalcetrapib compared with placebo (hazard ratio, 0.61; 95% confidence interval, 0.41–0.92). In patients with genotype GG, there was a 27% increase in events with dalcetrapib versus placebo. Ten single-nucleotide polymorphism in the ADCY9 gene, the majority in linkage disequilibrium with rs1967309, were associated with the effect of dalcetrapib on intima-media thickness (P<0.05). Marker rs2238448 in ADCY9, in linkage disequilibrium with rs1967309 (r2=0.8), was associated with both the effects of dalcetrapib on intima-media thickness in dal-PLAQUE-2 (P=0.009) and events in dal-OUTCOMES (P=8.88×10–8; hazard ratio, 0.67; 95% confidence interval, 0.58–0.78). Conclusions—The effects of dalcetrapib on atherosclerotic outcomes are determined by correlated polymorphisms in the ADCY9 gene. Clinical Trial Information—URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00658515 and NCT01059682

Effects of the P-Selectin Antagonist Inclacumab on Myocardial Damage After Percutaneous Coronary Intervention for Non–ST-Segment Elevation Myocardial Infarction : Results of the SELECT-ACS Trial

OBJECTIVES The study aimed to evaluate inclacumab for the reduction of myocardial damage during a percutaneous coronary intervention (PCI) in patients with non-ST-segment elevation myocardial infarction. BACKGROUND P-selectin is an adhesion molecule involved in interactions between endothelial cells, platelets, and leukocytes. Inclacumab is a recombinant monoclonal antibody against P-selectin, with potential anti-inflammatory, antithrombotic, and antiatherogenic properties. METHODS Patients (N = 544) with non-ST-segment elevation myocardial infarction scheduled for coronary angiography and possible ad hoc PCI were randomized to receive 1 pre-procedural infusion of inclacumab 5 or 20 mg/kg or placebo. The primary endpoint, evaluated in patients who underwent PCI, received study medication, and had available efficacy data (n = 322), was the change in troponin I from baseline at 16 and 24 h after PCI. RESULTS There was no effect of inclacumab 5 mg/kg. Placebo-adjusted geometric mean percent changes in troponin I with inclacumab 20 mg/kg were -24.4% at 24 h (p = 0.05) and -22.4% at 16 h (p = 0.07). Peak troponin I was reduced by 23.8% (p = 0.05) and area under the curve over 24 h by 33.9% (p = 0.08). Creatine kinase-myocardial band yielded similar results, with changes of -17.4% at 24 h (p = 0.06) and -16.3% at 16 h (p = 0.09). The incidence of creatine kinase-myocardial band increases >3 times the upper limit of normal within 24 h was 18.3% and 8.9% in the placebo and inclacumab 20-mg/kg groups, respectively (p = 0.05). Placebo-adjusted changes in soluble P-selectin level were -9.5% (p = 0.25) and -22.0% (p < 0.01) with inclacumab 5 and 20 mg/kg. There was no significant difference in adverse events between groups. CONCLUSIONS Inclacumab appears to reduce myocardial damage after PCI in patients with non-ST-segment elevation myocardial infarction. (A Study of RO4905417 in Patients With Non ST-Elevation Myocardial Infarction [Non-STEMI] Undergoing Percutaneous Coronary Intervention; NCT01327183).