Triple antiplatelet therapy vs. dual antiplatelet therapy in patients undergoing percutaneous coronary intervention: an evidence‐based approach to answering a clinical query

Triple antiplatelet therapy vs.dual antiplatelet therapy inpatients undergoingpercutaneous coronaryintervention: anevidence-based approach toanswering a clinical queryInderjeet Singh, Nusrat Shafiq, Promila Pandhi, Srinivas Reddy,

Smita Pattanaik, Yashpaul Sharma & Samir Malhotra

Postgraduate Institute of Medical Education and Research [PGIMER], Chandigarh City, India

CorrespondenceDr Samir Malhotra, MD, DM, FCP,Postgraduate Institute of MedicalEducation and Research [PGIMER],Chandigarh City, India.Tel: + 91 17 2275 5243Fax: + 91 17 2274 4401E-mail: samirmalhotra345@yahoo.com----------------------------------------------------------------------

Keywordsantiplatelet, cilostazol, coronary,intervention, percutaneous, triple----------------------------------------------------------------------

Received24 August 2008

Accepted18 February 2009

WHAT IS ALREADY KNOWN ABOUTTHIS SUBJECT?• Different strategies have been evaluated for their

efficacy in reducing stent thrombosis andrestenosis in patients undergoing percutaneouscoronary intervention (PCI).

• Triple antiplatelet therapy is one such strategythat has been shown to improve the efficacyoutcomes associated with PCI.

• Cilostazol is an antiplatelet agent that is beingprescribed as a component of triple-therapyregimen in various centres in our country, andthe beneficial effect of cilostazol addition toother antiplatelet regimens has been observed.

• However, the extent of the efficacy is notuniformly in favour of the triple therapycompared with dual therapy.

• Moreover, the use of this agent with bare metalstents (commonly used in developing countries)and drug-eluting stents has not been separatelylooked into.

WHAT THIS STUDY ADDS• Triple antiplatelet therapy, with cilostazol as a

component, reduces restenosis rates and repeatrevascularizations post PCI without anysignificant increase in bleeding risk.

• The beneficial effect of cilostazol is more evidentwith drug-eluting stents.

• Its use with bare metal stents needs to beexplored further.

AIMSOutcomes of patients undergoing percutaneous coronary intervention (PCI)with drug-eluting stents (DES) and bare metal stents (BMS) have not beenevaluated separately for specific dual and triple antiplatelet agent use. Thepurpose of this meta-analysis was to determine whether triple antiplatelettherapy (combination of clopidogrel, aspirin and cilostazol) has any advantagein efficacy compared with standard dual antiplatelet therapy (aspirin andclopidogrel) in patients undergoing PCI.

METHODSElectronic and printed sources were searched till May 2008 for randomizedcontrolled clinical trials (RCTs) of cilostazol in combination with aspirin andclopidogrel. Pooled weighted mean difference (WMD) and pooled odds ratio(OR) with 95% confidence intervals (CIs) were calculated.

RESULTSA total of four RCTs including 1457 patients with a median follow-up period of6–9 months were included in the analysis. The rates of major adverse cardiacand/or cerebrovascular events (MACE/MACCE), stent thrombosis and bleedingwere not significantly different between triple and dual antiplatelet therapygroups. Pooled analysis showed that cilostazol was associated with significantlydecreased incidence of in segment restenosis (ISR) (OR 0.51, 95% CI 0.38, 0.68;P < 0.00001), increased minimum luminal diameter (MLD) (WMD 0.16, 95% CI0.10, 0.22; P < 0.00001) for both DES and BMS and also individually. However, therates of target vessel revascularization (OR 0.45, 95% CI 0.25, 0.83; P = 0.01 andlate lumen loss (pooled WMD 0.14, 95% CI 0.2, 0.07; P = 0.001) were decreasedsignificantly only in the DES group receiving triple therapy.

CONCLUSIONSCilostazol appears to be effective in reducing the rates of ISR without anysignificant benefit for MACE/MACCE.

British Journal of ClinicalPharmacology

DOI:10.1111/j.1365-2125.2009.03402.x

4 / Br J Clin Pharmacol / 68:1 / 4–13 © 2009 The AuthorsJournal compilation © 2009 The British Pharmacological Society

mailto:[email protected]

Introduction

Recently we were faced with a clinical query regarding theusefulness of triple antiplatelet therapy (cilostazol, aspirinand clopidogrel combination) for patients undergoingpercutaneous transluminal coronary angioplasty in ourhospital. The underlying logic for off-label use of cilostazolin this setting is that cilostazol has been shown to inhibitvascular smooth muscle proliferation and intimal hyper-plasia after endothelial injury, in addition to its antiplateleteffect [1, 2]. As against this, currently used antiplateletdrugs such as aspirin and clopidogrel have no effect onneointimal hyperplasia. More importantly, randomizedclinical trials have shown the beneficial effect of cilostazolin reducing long-term major adverse cardiovascular andcerebrovascular events (MACCE) and preventing bothangiographic and clinical restenosis in patients [3, 4].However, the extent of the efficacy is not uniformly infavour of triple therapy vs. dual therapy.

The performance of bare metal stents (BMS) is subop-timal in terms of freedom from restenosis and repeat per-cutaneous coronary intervention (PCI) in lesions at highrisk of restenosis. Another aspect of management of thesepatients is that BMS are the most commonly used stents inour setting due to poor affordability of drug-eluting stents(DES). Thus there is a great need to prevent neointimalhyperplasia and stent restenosis. Some pharmacologicalagents have been investigated for their usefulness whenadded to the standard therapeutic regimen in reducingrestenosis rates when used in patients undergoing PCIwith BMS. However, this has largely been unsuccessful [4].

Ours is a tertiary care centre, and in recent yearsincreasing attempts have been made to incorporate prin-ciples of evidence-based medicine in guiding clinical prac-tice. Such evidence is also used in making policy-relateddecisions. These practices are based on reports that haveshown better therapeutic outcomes associated withevidence-based medicine [5, 6]. In order to provide an

Review: Triple Vs Dual antiplatelet therapy in post PCI patients

01 Triple (Aspirin+Clopidogrel+Cilostazol) vs Dual (Aspirin+Clopidogrel)

01 Triple vs Dual antiplatelet therapy in PCI with Bare Metal Stents

CREST

Chen et al

Subtotal (95% CI)

Total events: 77 (Treatment), 81 (Control)

Test for heterogeneity: Chi2 = 4.78, df = 1 (P = 0.03), I2 = 79.1%

Test for overall effect: Z = 0.72 (P = 0.47)

02 Triple vs Dual antiplatelet therapy in PCI with Drug Eluting Stents

DECLARE-Long

DECLARE-DIABETES

Subtotal (95% CI)


Test for heterogeneity: Chi2 = 0.06, df = 1 (P = 0.81), I2 = 0%Test for overall effect: Z = 2.92 (P = 0.004)

Total (95% CI) 864 861

7/250 19/250

72/354

5/60

414

67/351

14/60

411

33.23 1.08 [0.75, 1.57]

0.30 [0.10, 0.89]

0.63 [0.18, 2.20]

20.40

53.63

24.01 0.35 [0.14, 0.85]

0.41 [0.15, 1.09]

0.38 [0.20, 0.73]

22.36

46.37

0.51 [0.24, 1.08]100.00

0.1 0.2 0.5 1

Favours treatment Favours control

102 5

14/2006/200

450450

Total events: 90 (Treatment), 114 (Control)Test for heterogeneity: Chi2 = 10.77, df = 3 (P = 0.01), I2 = 72.1%


01 MACE/MACCE frequency

Comparison:

Outcome:

Study

or sub-category

Treatment Control OR (random)OR (random)

95% CI 95% CI

Weight

%n/N n/N

Figure 1Studies comparing major adverse cardiac event/major adverse cardiac and cerebrovascular event frequencies in triple and dual antiplatelet therapy groupsusing pooled odds ratio (OR)

Cilostazol based antiplatelet therapy in patients

Br J Clin Pharmacol / 68:1 / 5

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I. Singh et al.

6 / 68:1 / Br J Clin Pharmacol

evidence-based answer to the clinical query, which is per-tinent to the practice at our centre, we undertook a litera-ture search. During our preliminary literature search wecame across 30 studies and, interestingly, on the day ofquery we also came across a systematic review on thesame topic [7]. The main conclusions of the review werethat cilostazol was safe and effective in reducing the risk ofrestenosis and repeat revascularization without any signifi-cant increase in bleeding rates and incidence of stentthrombosis (ST). In the above meta-analysis, 23 studieswere analysed, of which only three compared the tripletherapy (clopidogrel based) with dual therapy. No sub-group analysis specifically addressed our query related tothe use of the triple regimen of aspirin, clopidogrel andcilostazol. With this background we undertook a meta-analysis to answer the query raised in cardiology practice.

Methods

Search strategy and study selectionWe systematically searched Medline, Cochrane CentralRegister of Controlled Trials, and Embsase for all relevantarticles up to May 2008. We first entered the medicalsubjects heading (MeSH) terms and text words, includingcilostazol AND percutaneous coronary intervention ANDstents. Next, we searched using the MeSH terms and textwords with antiplatelet therapy AND stents. Additionally,we entered these terms separately. Boolean logic was usedfor all searches. Two investigators carried out the searchindependently. We then combined all the searches andretrieved the relevant articles. Manual search was made bygoing through the reference lists of the retrieved articlesand through Index Medicus and key cardiology journals.Conference abstracts were obtained from conferencecoverages appearing in journals and other internet-basedsources.

Data extractionData extraction forms were used to obtain the followinginformation: characteristics of study participants, numberof participants, type of intervention (dose, duration),randomization, blinding, study outcomes and duration offollow-up. The data were extracted independently by twoinvestigators and compiled by a third investigator. Differ-ences were removed by consensus.

Randomized controlled trials of cilostazol in combi-nation with aspirin and clopidogrel (triple antiplatelettherapy) in patients undergoing PCI with BMS or DES wereincluded in the study. We planned to include only thoserandomized controlled clinical trials in which the patientsreceived clopidogrel and aspirin (dual antiplatelet therapy)in the control group. Exclusion criteria were the following:(i) studies that did not meet the inclusion criteria related toantiplatelet therapy, (ii) open label studies, (iii) studies withTa

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follow-up of <6 months, (iv) studies in which angiographicend-points were not evaluated, and (v) uncontrolledstudies.

Study outcomesThe primary end-point evaluated for the present analysiswas major adverse cardiac events (MACE) or MACCE. MACEincluded myocardial infarction (MI), symptom-drivenrepeat revascularization and death, and MACCE includedthe components MACE and stroke. Secondary end-pointswere (i) target vessel revascularization (TVR); (ii) ST, definedas any of the following: angiographic documentation ofstent occlusion with or without the presence of thrombusassociated with an acute ischaemic event, unexplainedsudden death, and MI not clearly attributable to anothercoronary lesion; (iii) death; (iv) in segment restenosis (ISR);(v) in segment late lumen loss (LL); (vi) in segmentminimum luminal diameter (MLD); and (vii) bleeding ratesat 6 or 9 months, major bleeding defined as a need fortransfusion, a reduction in haemoglobin of �5 g dl-1, needfor surgical intervention, or resulting in hypotensionrequiring inotropic support.

For all the evaluated variables, subgroup analysis wasundertaken to compare triple and dual antiplatelettherapy for patients undergoing PCI with BMS or DES.

Pertinent data were also extracted for assessment ofquality of the studies as described previously by Khan et al.[8]. Briefly, information related to randomization, baselinecomparability, blinding, withdrawal and intention-to-treatanalysis. Inverted funnel plot was generated for assess-ment of publication bias.

AnalysisContinuous data were expressed as mean (SD) andweighted mean difference (WMD) was obtained. The datafrom various studies were pooled and expressed as pooledWMD with 95% confidence interval (CI). Dichotomous datawere expressed as odds ratio (OR) with 95% CI. The datawere pooled by random effects model in case significantheterogeneity (detected by c2 test) was found, otherwisethe fixed effects model was used. A P-value <0.05 was con-sidered to be significant. Rosenthal File Drawer’s Methodwas used to evaluate the number of studies with conflict-ing results that would be required to change the findings




CREST

Subtotal (95% CI)


Test for heterogeneity: not applicable



DECLARE-Long

DECLARE-DIABETES

Subtotal (95% CI)


Test for heterogeneity: Chi2 = 0.05, df = 1 (P = 0.82), I2 = 0%Test for overall effect: Z = 2.56 (P = 0.01)

Total (95% CI) 804 801

9/250 18/250

54/354

354

56/351

351

48.66 0.95 [0.63, 1.42]

48.66 0.95 [0.63, 1.42]

27.30 0.48 [0.21, 1.09]

0.42 [0.17, 1.04]

0.45 [0.25, 0.83]

24.04

51.34

0.65 [0.37, 1.13]100.00

0.1 0.2 0.5 1


102 5

16/2007/200

450450

Total events: 70 (Treatment), 90 (Control)Test for heterogeneity: Chi2 = 4.00, df = 2 (P = 0.14), I2 = 50.0%


01 TVR in patients recieving dual or triple antiplatelet therapy

Comparison:

Outcome:

Study

or sub-category


95% CI 95% CI

Weight

%n/N n/N

Figure 2Studies comparing target vessel revascularization frequency in triple and dual antiplatelet therapy groups using pooled odds ratio (OR)

I. Singh et al.


of the analysis into statistically nonsignificant results.Revman (Version 4.2) was used for all the analyses.

Results

Thirty hits were obtained when the combined MeSH termswere used. From the initial search, 26 studies were consid-ered as potentially eligible. These were further evaluatedfor eligibility. Four were found to be eligible for inclusion inthis meta-analysis. Twenty-two were excluded becausethey did not meet the inclusion criteria. The study charac-teristics of the four included studies are shown in Table 1.The included studies satisfied most of the criteria forquality assessment (Table 2).

MACE/MACCE,TVR,ISR and MLD were reported in all thestudies,for a total population of 1725 patients.One study [9]did not report stent thrombosis and deaths,therefore theseend-points were evaluated for 1457 patients.

MACE/MACCEFour studies [9–12] including 1725 patients were includedfor this analysis. There was no difference in the incidenceof MACE/MACCE between the triple therapy and dualtherapy groups (pooled OR 0.51, 95% CI 0.25, 1.03;P = 0.06). However, on subgroup analysis there was a sig-nificant difference between the two groups favouring thetriple drug therapy in patients undergoing PCI with DES(OR 0.38, 95% CI 0.38, 0.72; P = 0.003) (Figure 1).

Target vessel revascularizationFour studies [9–12] including 1725 patients were includedfor this analysis.There was no difference in the incidence ofTVR between triple and dual antiplatelet therapy for thecombined analysis of BMS and DES (pooled OR 0.75,95% CI0.53, 1.04; P = 0.08). However, when the DES were consid-ered alone, there were significant differences between thetwo groups favouring triple drug therapy in patients with

Review:

A

Triple Vs Dual antiplatelet therapy in post PCI patients

04 Triple(Aspirin+Clopidogrel+Cilostazol) vs Dual (Aspirin+Clopidogrel)


CREST

Subtotal (95% CI)


Test for heterogeneity: not applicableTest for overall effect: Z = 0.01 (P = 1.00)

02 Triple vs Dual antiplatelet therapy in PCI with Drug Eluting StentsDECLARE-Long

DECLARE-DIABETES

Subtotal (95% CI)

Total events: 1 (Treatment), 2 (Control)Test for heterogeneity: Chi2 = 0.26, df = 1 (P = 0.61), I2 = 0%


Total (95% CI) 804 801

1/250 1/250

1/354

354

1/351

351

36.39 0.99 [0.06, 15.91]

36.39 0.99 [0.06, 15.91]

36.35 1.00 [0.06, 16.08]

0.33 [0.01, 8.19]

0.62 [0.08, 5.09]

27.27

63.61

0.74 [0.14, 3.94]100.00

0.001 0.01 0.1 1


100010 100

1/2000/200

450450


Test for heterogeneity: Chi2 = 0.33, df = 2 (P = 0.85), I2 = 0%


01 Stent Thrombosis in patients recieving dual or triple antiplatelet therapy

Comparison:

Outcome:

Study

or sub-category


95% CI 95% CI

Weight

%n/N n/N

Figure 3(a) Studies comparing stent thrombosis in triple and dual antiplatelet therapy groups using pooled odds ratio (OR). (b) Studies comparing number of deathsin triple and dual antiplatelet therapy groups using pooled OR



DES placement (pooled OR 0.45, 95% CI 0.25, 0.83; P = 0.01)(Figure 2).

Stent thrombosis and deathsThree studies [10–12] including 1457 patients wereincluded for this analysis. There was no difference in theincidence of stent thrombosis between triple and dual anti-platelet therapy for the combined analysis (pooled OR 0.75,95% CI 0.14, 3.62; P = 0.68).The same studies were analysedfor mortality. There was no difference in mortality duringthe follow-up periods between triple and dual antiplatelettherapy (pooled OR 1.00, 95% CI 0.29, 3.45; P = 0.99). Similarresults were seen on subgroup analysis (Figure 3a,b).

In segment restenosisFour studies [9–12] including 1725 patients were includedfor this analysis. The pooled OR of angiographic restenosisat 6 months was 0.51 (95% CI 0.38, 0.68; P = 0.00001), whichwas statistically significant in favouring triple therapy.Similar results were observed on subgroup analysis(Figure 4).

Minimum luminal diameterFour studies [9–12] including 1725 patients were includedfor this analysis. There was a significant difference in theMLD at the end of 6 months between the triple therapyand dual therapy groups with pooled WMD = 0.16 (95% CI0.10, 0.22; P < 0.00001). The MLD in the BMS and DES fol-lowed a similar trend. For BMS group pooled WMD was0.21 (95% CI 0.11, 0.31; P < 0.0001) and pooled WMD forDES group was 0.13 (95% CI 0.05, 0.21; P < 0.001).

Late lumen lossFour studies [9–12] including 1725 patients wereincluded for this analysis. The pooled WMD of late LL was-0.37 (95% CI -0.74, 0.01; P = 0.05), which was not statis-tically significant in favouring triple therapy. However, forthe DES the triple therapy resulted in significantly lesslate LL with a pooled WMD -0.14 (95% CI -0.21, -0.07;P = 0.001), whereas for the BMS pooled WMD -0.59 (95% CI-1.41, -0.22; P = 0.00001), triple therapy was found to bebeneficial in preventing late LL in both DES and BMSstented patients.

Review:

B

Triple Vs Dual antiplatelet therapy in post PCI patients


01 Triple vs Dual antiplatelet therapy in PCI with Bare Metal StentsCRESTSubtotal (95% CI)Total events: 3 (Treatment), 2 (Control)Test for heterogeneity: not applicableTest for overall effect: Z = 0.44 (P = 0.66)

02 Triple vs Dual antiplatelet therapy in PCI with Drug Eluting StentsDECLARE-LongDECLARE-DIABETESSubtotal (95% CI)Total events: 1 (Treatment), 2 (Control)Test for heterogeneity: Chi2 = 1.46, df = 1 (P = 0.23), I2 = 31.6%Test for overall effect: Z = 0.22 (P = 0.82)

Total (95% CI) 804 801

0/250 2/250

3/354354

2/351351

60.17 1.49 [0.25, 8.98]60.17 1.49 [0.25, 8.98]

20.97 0.20 [0.01, 4.15]3.02 [0.12, 74.46]0.74 [0.06, 10.62]

18.8639.83

1.12 [0.28, 4.49]100.00

0.001 0.01 0.1 1


100010 100

0/2001/200450450



01 Deaths in patients recieving dual or triple antiplatelet therapy

Comparison:

Outcome:

Study

or sub-category


95% CI 95% CI

Weight

%n/N n/N

Figure 3Continued

I. Singh et al.


BleedingThree studies [10–12] including 1457 patients wereincluded for this analysis. There was no significant differ-ence in bleeding episodes between the two groups(pooled OR 0.77, 95% CI 0.41, 1.44; P = 0.42) (Figure 5).

Publication biasFunnel plot was constructed using the OR values obtainedfrom MACE/MACCE. From the funnel plot the possibility ofpublication bias in the analysis could not be ruled out(Figure 6).

Discussion

The results of our study showed that addition of cilostazoldoes not significantly decrease the incidence of MACE orMACCE for the overall analysis of PCI with either DES orBMS. However, there was a significant reduction in MACEwith triple therapy in the subgroup of studies thatincluded patients who had undergone PCI with DES.Whereas MACE was consistently reduced with tripletherapy in the two studies done in patients with DES,results were conflicting in case of BMS. In the CREST study[10], the incidence of MACE was more in the triple therapy

group. The lesions and patient characteristics in DECLAREDIABETES [11] and DECLARE-Long [12] were different fromthose of Chen et al. [9] and the CREST study [10]. In theformer, patients were either diabetic or had long lesions. Itis likely that the benefits of triple therapy are more pro-nounced in patients with long lesions and in diabetics.Despite a higher event rate (18.3–23.3%) in the controlgroups in patients who underwent PCI with BMS, tripletherapy with cilostazol failed to show any beneficial effect.This is surprising, since the drugs used to coat the DES areaimed to do precisely what cilostazol was used for.

As against the primary end-point, triple antiplatelettherapy significantly reduced restenosis rates overall aswell as in subgroups of studies of BMS and DES. The anti-proliferative properties of cilostazol may have contributedto this beneficial effect. Restenosis rates have largely beenreduced by the DES. Addition of pharmacological agentswith the aim of reducing restenosis rates in patientsundergoing PCI with BMS has shown conflicting results[4]. As against this, cilostazol has consistently shownreduction in restenosis rates. The results of the previousmeta-analysis showed that cilostazol reduced the resteno-sis rate and repeat revascularization in patients undergo-ing PCI after acute coronary syndrome. Many of thestudies analysed had used BMS and it is known that BMS



01 Triple vs Dual antiplatelet therapy in PCI with Bare Metal StentsCREST

Subtotal (95% CI)Total events: 64 (Treatment), 109 (Control)Test for heterogeneity: Chi2 = 0.73, df = 1 (P = 0.39), I2 = 0%Test for overall effect: Z = 3.72 (P = 0.0002)

02 Triple vs Dual antiplatelet therapy in PCI with Drug Eluting StentsDECLARE-LongDECLARE-DIABETESSubtotal (95% CI)Total events: 27 (Treatment), 49 (Control)Test for heterogeneity: Chi2 = 0.13, df = 1 (P = 0.71), I2 = 0%Test for overall effect: Z = 2.62 (P = 0.009)

Total (95% CI) 684 693

14/210 23/205

57/259

311

92/267

3217/52Chen et al 17/54

56.51 0.54 [0.36, 0.79]8.80 0.34 [0.13, 0.90]

65.31 0.50 [0.35, 0.72]

17.59 0.57 [0.28, 1.13]0.47 [0.23, 0.95]0.52 [0.31, 0.85]

17.1034.69

0.51 [0.38, 0.68]100.00

0.1 0.2 0.5 1

Favours treatment Favours control102 5

26/16713/163372373


Test for overall effect: Z = 4.55 (P < 0.00001)

01 In segment restenosis rate in patients recieving dual or triple antiplatelet therapy

Comparison:

Outcome:

Study

or sub-category


95% CI 95% CI

Weight

%n/N n/N

Figure 4Studies comparing in-segment restenosis rates in triple and dual antiplatelet therapy groups using pooled odds ratio (OR)



is associated with an increased incidence of restenosis.Our subgroup results concur with the previous meta-analysis done by Biondi-Zoccai et al. [7] and support thataddition of cilostazol in patients with BMS reduces rest-

enosis rates. However, in that meta-analysis 13 out of 23studies analysed used ticlopidine as a part of an antiplate-let regimen. In our analysis we did not include studies thatused ticlopidine.

Stent thrombosis was not shown to be significantlyreduced by the use of cilostazol in either of the stentgroups. Similar results were seen in the study done byBiondi-Zoccai et al. [7]. Stent thrombosis is of specialconcern with DES, and cilostazol was not shown to affectthe incidence significantly. These data should be inter-preted cautiously, since stent thrombosis has an event rateof 1% at 1 year [13] and there is an incremental risk of stentthrombosis of 0.2–0.5% per year thereafter [14, 15]. Themaximum follow-up period of the pooled studies was 9months, hence the results of our meta-analysis do notreflect long-term events. Cilostazol was found to be safeconsidering the low bleeding risk. In our analysis there wasno significant difference between the dual and tripletherapy groups. An increased incidence of major andminor bleeding events was observed in patients receivingabciximab and cilostazol [16]. However, cilostazol use wasassociated with a significantly increased incidence of gas-trointestinal disturbance and rash when used in combina-tion with aspirin and clopidogrel [12].



01 Triple vs Dual antiplatelet therapy in PCI with Bare Metal StentsCRESTSubtotal (95% CI)Total events: 13 (Treatment), 16 (Control)Test for heterogeneity: not applicableTest for overall effect: Z = 0.59 (P = 0.55)


DECLARE-LongDECLARE-DIABETESSubtotal (95% CI)Total events: 5 (Treatment), 7 (Control)Test for heterogeneity: Chi2 = 0.34, df = 1 (P = 0.56), I2 = 0%Test for overall effect: Z = 0.55 (P = 0.58)

Total (95% CI) 804 801

2/250 4/250

13/354354

16/351351

71.10 0.80 [0.38, 1.69]71.10 0.80 [0.38, 1.69]

13.63 0.50 [0.09, 2.73]1.00 [0.20, 5.02]0.72 [0.22, 2.32]

15.2728.90

0.77 [0.41, 1.45]100.00

0.01 0.1 1


10010

3/2003/200450450



01 Bleeding rates in patients recieving dual or triple antiplatelet therapy

Comparison:

Outcome:

Study

or sub-category


95% CI 95% CI

Weight

%n/N n/N

Figure 5Studies comparing bleeding frequency in triple and dual antiplatelet therapy groups using pooled odds ratio (OR)

SE (log[OR])0

0.2

0.4

0.6

0.8

10.01 0.1 1 10 100

OR

Figure 6Funnel plot. Assessing publication bias using odds ratio (OR) of majoradverse cardiac event/major adverse cardiac and cerebrovascular eventfrequency of the included studies. Triple vs Dual antiplatelet therapy inPCI with Bare Metal Stents (�); Triple vs Dual antiplatelet therapy in PCIwith Drug Eluting Stents ( )

I. Singh et al.


Keeping in tune with the standard practice of our DrugInformation Unit, which received the query, we framed ourevidence-based answer as follows: ‘though triple therapysignificantly reduces restenosis rates compared to dualtherapy when given to patients with DES and/or BMS,there is no significant reduction in MACE/MACCE and stentthrombosis rate. However, for patients with long lesionsand patients receiving DES, triple antiplatelet therapysignificantly reduces incidence of MACE. There is nosignificant difference in bleeding rates, target vesselrevascularization and mortality in the two groups’.

It is well known that systematic reviews are associatedwith limitations, and the results obtained with thesemethods should be analysed accordingly. In our studypublication bias could not be ruled out. The numbers ofpatients analysed were too low to reflect the data on thewhole population.Clinical events such as stent thrombosis,bleeding and death were low in all the studies.

In conclusion, evidence needs to be generated for theuse of the triple therapy regimen in patients undergoingPCI with BMS who have long lesions or who are diabetic.More evidence is needed for the effect of triple therapy onlong-term follow-up.

Competing interests

None declared.

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Triple antiplatelet therapy vs. dual antiplatelet therapy in patients undergoing percutaneous coronary intervention: an evidence‐based approach to answering a clinical query

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