Johannes C. Kelder

Use of clopidogrel with or without aspirin in patients taking oral anticoagulant therapy and undergoing percutaneous coronary intervention: an open-label, randomised, controlled trial

BACKGROUND If percutaneous coronary intervention (PCI) is required in patients taking oral anticoagulants, antiplatelet therapy with aspirin and clopidogrel is indicated, but such triple therapy increases the risk of serious bleeding. We investigated the safety and efficacy of clopidogrel alone compared with clopidogrel plus aspirin. METHODS We did an open-label, multicentre, randomised, controlled trial in 15 centres in Belgium and the Netherlands. From November, 2008, to November, 2011, adults receiving oral anticoagulants and undergoing PCI were assigned clopidogrel alone (double therapy) or clopidogrel plus aspirin (triple therapy). The primary outcome was any bleeding episode within 1 year of PCI, assessed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00769938. FINDINGS 573 patients were enrolled and 1-year data were available for 279 (98·2%) patients assigned double therapy and 284 (98·3%) assigned triple therapy. Mean ages were 70·3 (SD 7·0) years and 69·5 (8·0) years, respectively. Bleeding episodes were seen in 54 (19·4%) patients receiving double therapy and in 126 (44·4%) receiving triple therapy (hazard ratio [HR] 0·36, 95% CI 0·26-0·50, p<0·0001). In the double-therapy group, six (2·2%) patients had multiple bleeding events, compared with 34 (12·0%) in the triple-therapy group. 11 (3·9%) patients receiving double therapy required at least one blood transfusion, compared with 27 (9·5%) patients in the triple-therapy group (odds ratio from Kaplan-Meier curve 0·39, 95% CI 0·17-0·84, p=0·011). INTERPRETATION Use of clopiogrel without aspirin was associated with a significant reduction in bleeding complications and no increase in the rate of thrombotic events. FUNDING Antonius Ziekenhuis Foundation, Strect Foundation.

Comparison of Platelet Function Tests in Predicting Clinical Outcome in Patients Undergoing Coronary Stent Implantation

Context High on-treatment platelet reactivity is associated with atherothrombotic events following coronary stent implantation. Objective To evaluate the capability of multiple platelet function tests to predict clinical outcome. Design, Setting, and Patients Prospective, observational, single-center cohort study of 1069 consecutive patients taking clopidogrel undergoing elective coronary stent implantation between December 2005 and December 2007. On-treatment platelet reactivity was measured in parallel by light transmittance aggregometry, Verify Now P2Y12 and Platelet works assays, and the IMPACT-R and the platelet function analysis system (PFA-100) (with the Dade PFA collagen/adenosine diphosphate (ADP) cartridge and Innovance PFA P2Y). Cutoff values for high on-treatment platelet reactivity were established by receiver operating characteristic curve (ROC) analysis. Main Outcome Measurement The primary end point was defined as a composite of all-cause death, nonfatal acute myocardial infarction, stent thrombosis, and ischemic stroke. The primary safety end point included TIMI (Thrombolysis In Myocardial Infarction) criteria major and minor bleeding. Results Kaplan-Meier analysis demonstrated that at 1-year follow-up, the primary end point occurred more frequently in patients with high on-treatment platelet reactivity when assessed by light transmittance aggregometry (52 [11.7%; 95% confidence interval {CI}, 8.9%-15.0%] vs 36 [6.0%;95%CI, 4.2%-8.2%] P.001; n=1049),Verify Now (54 [13.3%; 95% CI, 10.2%-17.0%] vs 37 [5.7%; 95% CI, 4.1%-7.8%]P.001; n=1052), Platelet works (33 [12.6%; 95% CI, 8.8%-17.2%] vs 21 [6.1%;95% CI, 3.8%-9.2%] P=.005; n=606), and Innovance PFA P2Y (18 [12.2%; 95%CI; 7.4%-18.6%] vs 28 [6.3%; 95% CI, 4.3%-8.9%] P=.02; n=588). ROC-curve analysis demonstrated that light transmittance aggregometry (area under the curve[AUC], 0.63; 95% CI, 0.58-0.68), Verify Now (AUC, 0.62; 95% CI, 0.57-0.67), and Platelet works (AUC, 0.61; 95% CI, 0.53-0.69) had modest ability to discriminate between patients with and without primary end point at 1-year follow-up. The IMPACT-R(n=905) and the Siemens PFA Collagen/ADP (n=812) were unable to discriminate between patients with and without the primary end point at 1-year follow-up (all AUCs included 0.50 in the CI). None of the tests identified patients at risk for bleeding. Conclusions Of the platelet function tests assessed, light transmittance aggregometry,Verify Now, Platelet works, and Innovance PFA P2Y were significantly associated with the primary end point. However, the predictive accuracy of these 4 tests was only modest. None of the tests provided accurate prognostic information to identify patients at higher risk of bleeding following stent implantation. Trial Registration clinical trials.gov Identifier: NCT00352014 [corrected].

Predictors of Coronary Stent Thrombosis: The Dutch Stent Thrombosis Registry

OBJECTIVES This study sought to comprehensively identify predictors of stent thrombosis (ST). BACKGROUND Given the devastating consequences of ST, efforts should be directed toward risk stratification to identify patients at highest risk for ST. METHODS Consecutive patients with angiographic ST were enrolled. Patients who did not suffer from a ST were randomly selected in a 2:1 ratio and were matched for: 1) percutaneous coronary intervention (PCI) indication; 2) same date of index PCI; and 3) same interventional center. RESULTS Of 21,009 patients treated with either a bare-metal or drug-eluting stent, 437 patients (2.1%) presented with a definite ST. A total of 140 STs were acute, 180 were subacute, 58 were late, and 59 were very late. Undersizing of the coronary stent, Thrombolysis In Myocardial Infarction flow grade <3, present malignancy, presence of intermediate coronary artery disease proximal and distal to the culprit lesion, dissection, lack of aspirin, bifurcation lesions, ejection fraction <30%, and younger age were associated with ST. The lack of clopidogrel therapy at the time of ST in the first 30 days after the index PCI (hazard ratio [HR]: 36.5, 95% confidence interval [CI]: 8.0 to 167.8), between 30 days and 6 months after the index PCI (HR: 4.6, 95% CI: 1.4 to 15.3), and beyond 6 months (HR: 5.9, 95% CI: 1.7 to 19.8) after the index PCI was strongly associated with ST. CONCLUSIONS Important correlates of ST were identified. Discontinuation of clopidogrel, undersizing of the coronary stent, present malignancy, and intermediate (>or=50% to <70% stenosis) coronary artery disease proximal to the culprit lesion were the strongest predictors of ST.

Primary Stenting of Totally Occluded Native Coronary Arteries II (PRISON II) A Randomized Comparison of Bare Metal Stent Implantation With Sirolimus-Eluting Stent Implantation for the Treatment of Total Coronary Occlusions

Background— Sirolimus-eluting stents markedly reduce the risk of restenosis compared with bare metal stents. However, it is not known whether there are differences in effectiveness between bare metal and sirolimus-eluting stents in patients with total coronary occlusions. Methods and Results— In a prospective, randomized, single-blind, 2-center trial, we enrolled 200 patients with total coronary occlusions: Half (n=100) were randomly assigned to receive bare metal BxVelocity stents and half (n=100) to receive sirolimus-eluting Cypher stents. The primary end point was angiographic binary in-segment restenosis rate at 6-month follow-up. Secondary end points were a composite of major adverse cardiac events, target vessel failure, binary in-stent restenosis rate, in-stent and in-segment minimal lumen diameter, percent diameter stenosis, and late luminal loss at 6-month follow-up. The sirolimus stent group showed a significantly lower in-stent binary restenosis rate of 7% compared with 36% in the bare metal stent group (P<0.001). The in-segment binary restenosis rate was 11% in the group receiving a sirolimus stent versus 41% in the bare metal stent group (P<0.0001), resulting in a target lesion revascularization rate of 4% in the sirolimus group versus 19% in the bare metal group (P<0.001). Patients who received the drug-eluting stent also had significantly lower rates of target vessel revascularization, target vessel failure, and all major adverse cardiac events. Conclusions— In patients with total coronary occlusions, use of the sirolimus-eluting stents are superior to the bare metal stents with significant reduction in angiographic binary restenosis, resulting in significantly less need for target lesion and target vessel revascularization.

Long-term clinical outcome after a first angiographically confirmed coronary stent thrombosis: an analysis of 431 cases.

Background— There are limited data on the long-term clinical outcome after an angiographically confirmed (definite) stent thrombosis (ST). Methods and Results— Four hundred thirty-one consecutive patients with a definite ST were enrolled in this multicenter registry. The primary end point was the composite of cardiac death and definite recurrent ST. Secondary end points were all-cause death, cardiac death, definite recurrent ST, definite and probable recurrent ST, any myocardial infarction, and any target-vessel revascularization. The primary end point occurred in 111 patients after a median follow-up of 27.1 months. The estimated cumulative event rates at 30 days and 1, 2, and 3 years were 18.0%, 23.6%, 25.2%, and 27.9%, respectively. The cumulative incidence rates of definite recurrent ST, definite or probable recurrent ST, any myocardial infarction, and any target-vessel revascularization were 18.8%, 20.1%, 21.3%, and 32.0%, respectively, at the longest available follow-up. Independent predictors for the primary end point were diabetes mellitus, total stent length, severe calcification, American College of Cardiology/American Heart Association B2-C lesions, TIMI (Thrombolysis In Myocardial Infarction) flow grade <3 after percutaneous coronary intervention, and left ventricular ejection fraction <45%. The implantation of an additional coronary stent during the first ST was also associated with unfavorable outcome. Clinical outcome was not affected by the type of previously implanted stent (drug-eluting or bare-metal stent) or the category of ST (early versus late). Conclusions— The long-term clinical outcome after a first definite ST is unfavorable, with a high mortality and recurrence rate. Diabetes mellitus, left ventricular ejection fraction <45%, long total stent length, complex coronary lesions, TIMI flow grade <3 after percutaneous coronary intervention, and implantation of an additional coronary stent during the emergent percutaneous coronary intervention for the ST were associated with this unfavorable outcome.

Staged Carotid Angioplasty and Stenting Followed by Cardiac Surgery in Patients With Severe Asymptomatic Carotid Artery Stenosis Early and Long-Term Results

Background— The strategy for treating patients with severe asymptomatic carotid artery stenosis and cardiac disease remains unresolved. Staged or combined carotid endarterectomy in these patients offers the potential benefit of decreased neurological morbidity during and after cardiac surgery; however, in high-risk patients with severe coronary artery disease, chronic obstructive pulmonary disease, or renal impairment, the incidence of death and stroke is significantly higher. Methods and Results— We report the results of a prospective, single-center study designed to evaluate the feasibility and safety of carotid artery angioplasty and stenting (CAS) before cardiac surgery in neurologically asymptomatic patients. The periprocedural and long-term outcomes of 356 consecutive patients who underwent CAS before cardiac surgery were analyzed. The procedural success rate of CAS was 97.7%. The death and stroke rate from time of CAS to 30 days after cardiac surgery was 4.8% (n=17). The myocardial infarction rate from time of CAS to 30 days after cardiac surgery was 2.0% (n=7), and the combined death, stroke, and myocardial infarction rate was 6.7% (n=24). Distal embolic protection devices were used in 40% of the cases. Conclusions— This large cohort of asymptomatic patients who underwent staged CAS and cardiac surgery experienced a low periprocedural complication rate. The high rate of freedom from death and stroke during the 5 years of follow-up supports the long-term durability of this approach. Our findings suggest that this new strategy may become a valuable alternative in the treatment of patients with combined carotid and cardiac disease.

Three-year clinical outcome after primary stenting of totally occluded native coronary arteries: a randomized comparison of bare-metal stent implantation with sirolimus-eluting stent implantation for the treatment of total coronary occlusions (Primary Stenting of Totally Occluded Native Coronary Arteries [PRISON] II study).

BACKGROUND The purpose of this study was to examine the 3-year clinical outcome in patients enrolled in the Primary Stenting of Totally Occluded Native Coronary Arteries II study. METHODS Patients with totally occluded coronary arteries randomized to either sirolimus-eluting Cypher stents (SESs) (Cordis, a Johnson & Joshson Company, Miami Lakes, FL) (100 patients) or bare-metal BxVelocity stents (BMSs) (Cordis) (100 patients) were followed clinically for 3 years. RESULTS Between 1 and 3 years, there were infrequent additional clinical events that were equally distributed between the SES and the BMS group. After 3 years, target lesion revascularization was 7% in the SES group versus 27% in the BMS group (P < .001); and target vessel revascularization was seen in 11% in the SES group versus 30% in the BMS group (P = .002). Major adverse cardiac events were noted in 10% of the SES group versus 34% in the BMS group (P < .001). There were no statistically significant differences in death, myocardial infarction, and stent thrombosis according to the Academic Research Consortium criteria between the 2 groups. CONCLUSIONS Clinical outcome up to 3 years after implantation of SESs for total coronary occlusions continues to demonstrate a significant reduction in adverse clinical events compared with BMSs without the evidence for either disproportionate late restenosis or late stent thrombosis.

High on-treatment platelet reactivity to both aspirin and clopidogrel is associated with the highest risk of adverse events following percutaneous coronary intervention

Aim High on-clopidogrel platelet reactivity (HCPR) and high on-aspirin platelet reactivity (HAPR) are associated with atherothrombotic events following coronary stenting. There are, however, few data concerning high on-treatment platelet reactivity to both aspirin and clopidogrel simultaneously. The aim of the present study was to determine the incidence of dual high on-treatment platelet reactivity (DAPR) and its impact on clinical outcome. Methods On-treatment platelet reactivity was measured in parallel by ADP- and arachidonic acid-induced light transmittance aggregometry (LTA) (n=921) and the point-of-care VerifyNow system (P2Y12 and aspirin) (n=422) in patients on dual antiplatelet therapy undergoing elective stent implantation. HCPR and HAPR were established by receiver-operator characteristic curve analysis. The primary endpoint was a composite of all-cause death, non-fatal acute myocardial infarction, stent thrombosis and ischaemic stroke at 1-year follow-up. Results The incidence of DAPR varied between 14.7% and 26.9% depending on the platelet function test used. DAPR, assessed by LTA and the VerifyNow system, was highly associated with an adverse clinical outcome. At 1-year follow-up the primary endpoint occurred more frequently in patients with isolated HCPR (11.7%), isolated HAPR (9.6%) or DAPR (10.7%) compared with patients without high on-treatment platelet reactivity (4.2%, all p<0.01) when platelet function was evaluated with LTA. Using the VerifyNow system, patients exhibiting DAPR had the highest risk for the primary endpoint (17.7% vs 4.1% in patients without high on-treatment platelet reactivity, p=0.001). Conclusions In patients undergoing elective percutaneous coronary intervention, DAPR to aspirin and clopidogrel is present in one in five patients and is associated with a high risk for atherothrombotic events. DAPR measured by the point-of-care VerifyNow system has a higher predictability for atherothrombotic events than LTA. Clinical Trial Registration Information www.clinicaltrials.gov: NCT00352014.

Preprocedural serum levels of acute-phase reactants and prognosis after percutaneous coronary intervention.

OBJECTIVE In this study we evaluate the value of baseline concentrations of acute-phase reactants on prognosis after percutaneous coronary intervention (PCI). METHODS Blood samples were drawn immediately before PCI to measure baseline concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), lipoprotein(a) (Lp(a)), and fibrinogen. Follow-up data were collected at 8 months. Repeat PCI, CABG, myocardial infarction, and death were recorded as major adverse clinical events (MACE). Furthermore the recurrence of angina pectoris was noted. RESULTS The study included 600 consecutive patients after a successful PCI. Sixty-four percent of the patients were stented. The mean age was 61.6 years and 68.9% were male. CRP levels were significantly higher in patients who were to have repeat angina as compared with those who were not (P=0.0322). IL-6 levels were not correlated with angina or MACE. Lp(a) and fibrinogen concentrations were both significantly related to MACE (P=0.0337 and P=0.0253, respectively). CONCLUSION Our study clearly supports the role of inflammation in restenosis after PCI as measured in statistically higher levels of Lp(a) and fibrinogen in patients with MACE and CRP in patients with repeat angina.

Effect of Coumarins Started Before Coronary Angioplasty on Acute Complications and Long-Term Follow-Up A Randomized Trial

BACKGROUND Coronary angioplasty frequently creates a thrombogenic surface, with subsequent mural thrombosis that may lead to acute complications and possibly stimulates the development of restenosis. Whether coumarins can prevent these complications is unclear. The objective of this open, randomized trial was to assess the clinical effect of coumarins started before coronary angioplasty and continued for 6 months. METHODS AND RESULTS Before coronary angioplasty, 530 patients were randomly assigned to aspirin plus coumarins and 528 patients to aspirin alone. At the start of the angioplasty, the mean international normalized ratio was 2.7+/-1.1; during follow-up, it was 3.0+/-1.1. At 30 days, the composite end point of death, myocardial infarction, target-lesion revascularization, and stroke was observed in 18 patients (3.4%) treated with aspirin plus coumarin compared with 34 patients (6.4%) treated with aspirin alone (relative risk, 0.53; 95% CI, 0.30 to 0.92). At 1 year, these figures were 14.3% and 20.3%, respectively (relative risk, 0.71; 95% CI, 0.54 to 0.93). The incidence of major bleeding and false aneurysm during hospitalization was 3.2% and 1.0%, respectively (relative risk, 3.39; 95% CI, 1.26 to 9.11). The benefit of coumarins was observed in both stented and nonstented patients. CONCLUSIONS Coumarins in addition to aspirin started before PTCA and continued for 6 months was more effective than aspirin alone in the prevention of acute and late complications after coronary angioplasty. This benefit was accompanied by a small but significant increase in bleeding complications.