The Value of Screening for "High on Treatment Platelet Reactivity" in Patients Undergoing Lower Extremity Arterial Endovascular Interventions
Phase: PHASE3
Conditions: Peripheral Artery Disease, Clopidogrel, Poor Metabolism of, Peripheral Vascular Disease, Artery Disease, Peripheral Arterial Occlusive Disease
Sponsor: Marissa Jarosinski

Routine Testing for High on Treatment Platelet Reactivity in Patients After Lower Extremity Arterial Endovascular 
Interventions 
 
 
 
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Efthymios Avgerinos, MD, PhD, MsC 
Assistant Professor of Surgery 
Division of Vascular Surgery 
412-802-3031 (phone) 
412-291-1669 (fax) 
avgerinose@upmc.edu 
 
 

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INTRODUCTION 
Background and Significance 
 
Peripheral arterial disease (PAD) affects millions of people worldwide1,2. Management of PAD has evolved from open 
surgery to an endovascular first approach leading to increased volume of endovascular interventions3. Endovascular 
femoropopliteal intervention has emerged as a standard treatment for symptomatic PAD with acceptable patency rates4-6. 
 
Histologic observation of bare metal stents with early failure shows association with platelet rich thrombus, and high 
counts of platelets and neutrophils associated with stent struts7,8. Additionally, high inflation pressures associated with 
balloon angioplasty often causes local tissue damage leading to platelet activation. Identifying role of platelet activation in 
endovascular treatment failures contributes to current practice standards of prescribing antiplatelet medication following 
endovascular intervention.  
 
Current standard of care is prescription of dual antiplatelet therapy (DAPT) for femoropopliteal angioplasty or stenting. 
DAPT is active use of any two anti-platelet agents, often low dose aspirin plus P2Y12 inhibitor (clopidogrel, ticagrelor, 
prasugrel)9. There is improved stent patency and reduced adverse cardiovascular events in patients taking DAPT versus 
aspirin monotherapy10-13. 
 
Clopidogrel is the most common additional antiplatelet agent prescribed, but 4-30% of patients taking clopidogrel fail to 
achieve clinically expected platelet inhibition. This persistent platelet reactivity is commonly referred to as high on-
treatment platelet reactivity (HPR) despite compliant antiplatelet use and increases risk of endovascular intervention 
failure and associated adverse clinical events in these patients15-17. Clopidogrel is a pro-drug metabolized by CYP2C19 
enzyme into its active form. Failure to respond appropriately to clopidogrel is largely due to genetic polymorphisms 
within CYP2C19 enzyme resulting in variable metabolization of clopidogrel into the active metabolite14. 
 
Alternative antiplatelet medications can overcome HPR through different metabolic pathways. Of these, ticagrelor is 
often used to overcome HPR for patients taking clopidogrel with favorable outcomes18. Overall, there is paucity of 
evidence looking at HPR and lower extremity arterial endovascular interventions without consensus or guidelines on 
how to address this problem. Thus, we propose an unblinded, randomized control trial comparing testing and treating for 
HPR versus not testing for HPR with guideline based therapy in patients having femoropopliteal angioplasty or stenting. 
 
Preliminary Studies 
 
The MIRROR trial first demonstrated the benefit of DAPT in patients with lower extremity interventions. Subgroup 
analysis of the DAPT treatment arm showed that of the failures, XX% were resistant to clopidogrel based on XX testing. 
Spiliopoulos et al, reported 64% target lesion re-intervention (TLR) in patients with HPR on clopidogrel versus 8% TLR in 
non-HPR for superficial femoral artery interventions17. VerifyNow system was used for HPR testing and defined as >234 
platelet reactivity units (PRU). Guo et al reported 34.6% primary patency for superficial femoral artery interventions in 
patients with reduced CYP2C19 activity compared with 73.1% in those with non-HPR19. Bernlochner et al reported similar 
patency rates in patients with HPR versus non-HPR who had lower extremity arterial interventions21. However, they only 
required one month of DAPT. Furthermore, the Journal for Vascular Surgery recently published a summary on 
antiplatelet resistance and concluded that there was not enough evidence to recommend any clinical recommendations22.  
Public Health Relevance Statement 
 
Lower extremity arterial endovascular intervention is first line treatment for symptomatic peripheral arterial disease. 
Current evidence suggests that antiplatelet medication prolongs patency of these interventions. Standard of care is 
prescribing clopidogrel and low dose aspirin for patients having femoropopliteal interventions. Patients with HPR 
following standard of care are at risk of early stent failure resulting in re-interventions, potential limb loss, and increased 
cost. Our research will add the first randomized data about how to address HPR in lower extremity arterial endovascular 
interventions. 
 
Environment: Facilities and Other Resources Statement 
 
University of Pittsburgh is a large volume, multicenter, tertiary care center with over 175 specialties. Our research effort 
will be limited to our flagship hospital and primary referral center, UPMC Presbyterian hospital which has 795 beds;  UPMC 
Shadyside with close to 520 beds; UPMC Passavant with over 399 beds; and UPMC St. Margaret with close to 249 beds. 
These locations perform over 700 lower extremity angiograms and perform over 300 femoropopliteal angioplasty or stent 

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procedures annually. Each site is equipped with biplaner fluoroscopy, radiology and nursing staff, VerifyNow testing 
system, and available research personell.  
 
Outpatient hospital clinics are located at UPMC Shadyside, UPMC Passavant, and UPMC St. Margaret. All of our clinics 
are staffed with board certified vascular surgeons, physician extenders, nurses, and medical assistants. Additionally, each 
of our clincis has their own non-invasive vascular lab capable of performing both physiologic arterial testing and duplex 
ultrasound evaluation to help diagnose patency. 
 
Our dedicated research team includes 2 research coordinators and a biostatistician with extensive experience in trial design 
and execution. Our resarch coordinators are trained in phlebotomy with primary offices at UPMC Shadyside. However, 
our staff routinely travels to all sites and has ability to transport specimens to desired locations. All research sites are staffed 
with board certified vascular surgeons, integrated vascular surgery residents, and vascular surgery fellows who will 
perform the procedures.  
 
High on-treatment reactivity will be tested for using both VerifyNow testing system and pharmacogenetic testing. All 
research sites are equipped with VerifyNow testing systems. Pharmacogenetic testing is performed at UPMC presbyterian 
campus through the pharmacogenetics department. Our pharmacogentic department is a leader in studying high on-
treatment reactivity and has a validated testing strategy. All specimens will be stored in generator backed up freeze with 
phone allerting system for any malfunction. 
 
RESEARCH PLAN 
SPECIFIC AIMS  
 
Primary Outcome: 
 
Primary Research Question: In patients having femoropopliteal arterial endovascular interventions, should routine HPR 
testing and treatment be performed? 
 
Hypothesis: Routine testing for HPR will identify patients at risk for early stent failure. Switching patients with HPR to 
ticagrelor will improve patency of intervention compared to non-HPR patients. 
 
Primary response variable: one-year primary patency 
• 
Definitions: 
o 
One year- 365 days from date of intervention 
o 
Primary patency is a binary variable defined as the following at the site of original intervention: 
§ 
Freedom from reintervention 
§ 
Less than 80% stenosis on duplex ultrasound 
§ 
Less than 70% stenosis on computed tomography angiography 
§ 
Freedom from complete vessel thrombosis 
• 
Justification: primary patency is one of the most reported outcomes when assessing lower extremity arterial 
interventions. Clear definition of primary patency is the most reproducible outcome data with regards to 
interventional success. 
• 
Ascertainment: standard surveillance of patients receiving lower extremity endovascular interventions occur at a 
minimum of 1,6,12 months.  
 
Secondary Outcomes: 
 
1. Research Question: What is the one-year primary assisted patency of femoropopliteal balloon angioplasty or stenting 
compared to non-HPR patients? 
 
Hypothesis: Patients with HPR will have reduced one-year primary assisted patency compared to patients with non-
HPR 
 
• 
Response variable: One-year primary assisted patency 
• 
Description: One-year assisted primary patency is a binary variable measuring stent patency after 
reintervention following loss of primary patency (excluding stent thrombosis-see outcome number 2). This 
outcome will be monitored for 365 days following initial stent placement/enrollment. 

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• 
Ascertainment: standard surveillance of patients receiving lower extremity endovascular interventions occur 
at a minimum of 1,6,12 months.  
 
2. Research Question: What is the one-year secondary patency of femoropopliteal balloon angioplasty or stenting 
compared to non-HPR patients? 
 
Hypothesis: Patients with HPR will have reduced one-year secondary patency compared to patients with non-HPR 
 
• 
Response variable: One-year secondary patency 
• 
Description: One-year secondary patency is a binary variable measuring patency after reintervention 
specifically for complete thrombosis and thus loss of primary patency. Stent is defined as patent if it is open to 
any degree. This outcome will be monitored for 365 days following initial stent placement/enrollment. 
• 
Ascertainment: standard surveillance of patients receiving lower extremity endovascular interventions occur 
at a minimum of 1,6,12 months.  
 
3. Research Question: What is the one-year amputation free survival of patients with HPR versus non-HPR following 
femoropopliteal balloon angioplasty or stenting? 
 
Hypothesis: Patients with HPR will have decreased one-year amputation free survival compared to patients with 
non-HPR 
 
• 
Response variables: amputation and mortality 
• 
Description: Amputation is defined as surgical removal of tissue and bone from ipsilateral lower extremity. 
This will be tracked for 365 days following initial stent placement. This will be further subdivided into major 
and minor amputation. Major amputation defined as amputation proximal to the ankle joint and minor 
amputation defined as amputation distal to the ankle joint. Death is defined by sustained loss of pulse and 
ability to breathe. 
• 
Ascertainment: standard surveillance of patients receiving lower extremity endovascular interventions occur 
at a minimum of 1,6,12 months at which time patient interview, questionnaire, and chart review will be 
performed.  
 
4. Research Question: What is the prevalence of HPR in our patient population following femoropopliteal balloon 
angioplasty or stenting? 
 
Hypothesis: Local HPR prevalence will range between 25-30% 
 
• 
Response variable: HPR 
• 
Description: Positive HPR test will be defined as follows: 
o 
VerifyNow testing system- results greater than 234 platelet reactivity units (PRU)  
o 
CYP2C19 pharmacogenetic testing- poor metabolizers (PM) and intermediate metabolizers (IM) 
• 
Ascertainment: VerifyNow testing will be performed day of procedure and pharmacogenetic testing will be 
performed at end of study. 
 
5. Research Question: What is the difference in major adverse cardiovascular events (MACE) in HPR versus non-HPR 
patients following femoropopliteal artery balloon angioplasty or stenting? 
 
Hypothesis: Patients with HPR will have increased MACE compared to patients with non-HPR 
 
• 
Response variable: composite of myocardial infarction, stroke, and death 
• 
Description: Myocardial infarction is defined by EKG changes, elevated troponin, and chest pain confirmed by 
cardiologist. Stroke is defined by any neurological change associated with brain imaging showing new infarct 
confirmed by neurologist. Death is defined by sustained loss of pulse and ability to breathe.  
• 
Ascertainment: standard surveillance will occur at 1,6,12 months at which time patient interview and 
questionnaire will be performed. Additional chart review will be performed as needed. 
 

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6. Research Question: How do results of VerifyNow testing system correlate with pharmacogenetic testing of CYP2C19 
polymorphisms in patients having femoropoplital arterial endovascular interventions? 
 
Hypothesis: Pharmacogenetic testing and VerifyNow testing system results will not be statistically different.  
 
• 
Response variable: PRU>234 for VerifyNow testing system ; poor metabolizers and intermediate metabolizers 
with genetic testing. 
• 
Description: We will test for a difference in HPR detection between the two testing methods.   
• 
Ascertainment: VerifyNow testing will only be administered to half the patients and  those who have loss of 
patency. Every study subject will have pharmacogenetic testing performed at end of study. 
 
DESIGN 
 
Design: Open label phase III randomized clinical trial (RCT) comparing routine testing and treating for HPR versus no 
testing with guideline based care for HPR in patients with lower extremity arterial disease undergoing balloon angioplasty 
or stenting of superficial femoral artery or popliteal artery. 
• 
Treatment arm: Routine HPR testing using VerifyNow testing system on all patients the day of intervention. Patients 
with HPR will be prescribed ticagrelor instead of clopidogrel. All patients will have pharmacogenetic testing for 
CYP2C19 polymorphisms after trial completion.  
• 
Control arm: no initial HPR testing. All patients prescribed clopidogrel. All patients will have pharmacogenetic testing 
for CYP2C19 polymorphisms after trial completion.  
 
Allocation Ratio: 1:1 between treatment arm and control arm 
 
Randomization Plan: Fixed block randomization with random block size. We will stratify based on patients who received 
a stent. Randomization will be generated by STATA and uploaded in REDcap. Randomization allocation will be 
computer generated and obtained by member of research team prior to date of procedure.  
 
Blinding:  This will be an unblinded study 
• 
Justification: Test results will need to be available to clinical team to switch HPR patients to ticagrelor. Ticagrelor is 
twice a day dosing compared to clopidogrel which is daily. This difference can be realized by both patients and 
surgeons. So, these factors prevent blinding. The cost of medication blinding is too expensive and is not feasible for 
this study. 
 
PARTICIPANTS AND RECRUITMENT 
 
The study population will be comprised of patients with peripheral arterial disease undergoing lower extremity 
endovascular balloon angioplasty or stenting of superficial femoral artery or popliteal artery. 
 
Inclusion criteria:  
• 
Inpatients or outpatients 
Justification: population of interest. 
• 
18-90 years of age 
Justification: population of interest 
• 
Patients with peripheral arterial disease and  preoperative imaging suggestive of superficial femoral artery or 
popliteal artery disease amenable to angioplasty or stenting. 
Justification: population of interest. Will allow for patients to randomized and consented prior to date of procedure 
 
Exclusion criteria:  
• 
Patients treated on an emergency basis 
Justification: pathology of patients treated urgently often includes higher thrombus burden which introduces 
treatment bias. 
• 
Planned intervention on prior site of open surgical intervention (autogenous or autologous bypass, endarterectomy, 
or patch angioplasty) 
Justification: Sites of prior surgical repair undergo variable levels of postoperative inflammation, fibrosis, and vessel 
geometry which can greatly effect outcome, and are difficult to adjust for. 

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• 
Planned intervention at site exclusive of superficial femoral artery or popliteal artery 
Justification: site of treatment outside the scope of this study 
• 
Planned re-stenting at site of prior stent placement 
Justification: Prior stent placement potentially restricts the effectiveness of additional stent and introduces selection 
bias 
• 
Patients less than 18 years old or greater than 90 years old 
Justification: Not our population of interest 
• 
Planned re-angioplasty at site of prior angioplasty 
Justification: Intervening on the same site introduces selection bias 
• 
Known inability to tolerate antiplatelet regimen before enrollment 
Justification: Overall effect size is determined by effectiveness of antiplatelet medication. If patients are known to be 
intolerant to antiplatelet medications they will introduce error to study. 
• 
Patients who plan on receiving follow up care outside the UPMC system 
Justification: Portion of patients treated at our institution know a-priori that they will follow up at outside 
institutions. We want to reduce loss to follow up. 
• 
Current use of prasugrel 
Justification: this is a similar antiplatelet medication to ticagrelor that may confound results 
• 
Current use of oral anticoagulation medication 
Justification: concomitant use of oral anticoagulation will likely confound results 
 
SCREENING AND ENROLLMENT: 
 
Screening and Enrollment Protocol: Outpatients scheduled for lower extremity angiography procedures will be flagged 
and disclosed to research team while in clinic or by secure email.  Diagnostic imaging will be reviewed by medical staff. 
Research team will contact patients to discuss study, answer inclusion/exclusion criteria, and review study protocol. 
Patients meeting eligibility criteria and willing to participate in study will be randomized 
 
HPR Testing Protocol: We will use both VerifyNow and CYP2C19 genetic testing to identify HPR in study subjects. 
 
Treatment Arm: VerifyNow testing will be performed the day of procedure. Blood sample for genetic testing will 
be collected on day of procedure or at follow up visit for genetic testing to be performed at conclusion of 
study. 
Control Arm: No initial testing. Blood sample for genetic testing will be collected on day of procedure or at follow 
up visit for genetic testing to be performed at conclusion of study. 
 
• 
VerifyNow testing will be ordered through UPMC laboratory, collected by UPMC nurses, and billed to 
research account. Testing results will be available in electronic medical record.   
• 
Pharmacogenetic testing will be obtained by research team in purple top tube. This sample must be refrigerated 
and transported to pharmacogenetics laboratory in cooler within 5 days of sample collection. The research team 
will take this sample to pharmacogenetics lab where it will be frozen for later analysis.  
 
Antiplatelet Prescribing Protocol: VerifyNow testing system requires therapeutic drug levels at time of testing for accurate 
results. So, all patients need to be on clopidogrel prior to testing: 
1. Patients already taking aspirin and 75mg clopidogrel daily will be continued on these medications without 
modification 
2. Patients who are not taking aspirin will be prescribed 81mg aspirin daily to begin immediately. 
3. Patients who are not on clopidogrel will be prescribed clopidogrel as follows: 
a. If angiography is scheduled more than 7 days out from initial encounter: 
i. Prescribe clopidogrel at 75mg daily to begin at the time of scheduling angiography.  
b. If angiography is scheduled less than 7 days from first patient encounter: 
i. Prescribe a one-time, single loading dose of 300mg clopidogrel 
AND  
ii. Prescribe clopidogrel 75mg daily to begin the day after the loading dose 
c. 
Research team will call patient within a week of scheduled procedure to verify adherence to this protocol. 
If patient fails to follow prescription instructions: 
i. Instruct patient to take a one-time, single loading dose of 300mg clopidogrel (4 tablets) 

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AND  
ii. Instruct patient to take clopidogrel 75mg daily to begin the day after the loading dose 
4. Antiplatelet therapy will be prescribed for at least one year following intervention.  
5. After one year, continuation of antiplatelet medication is solely at discretion of patient and physician 
 
Angiography Protocol: All angiograms will be performed by board certified vascular surgeons. Angiograms will be 
performed using standard fluoroscopy at one of several approved locations: UPMC Presbyterian, UPMC, Shadyside, 
UPMC Passavant, or UPMC St. Margaret. Procedural technique will remain completely at the discretion of the surgeon.  
 
Follow up protocol:  
 
1 month follow up: 
• 
Case report form 
• 
Peripheral vascular laboratory testing 
6 month follow up: 
• 
Case report form 
• 
Peripheral vascular laboratory testing 
12 month follow up: 
• 
Case report form 
• 
Peripheral vascular laboratory testing 
 
Justification: This is standard follow up schedule 
 
Peripheral vascular testing protocol: 
 
§ 
Duplex testing 
§ 
Angioplasty protocol 
• 
Color Doppler Imaging 
o 
At location of intervention 
• 
Spectral Doppler 
o 
Common femoral artery (CFA) 
o 
Superficial femoral artery (SFA) 
o 
Popliteal artery (POP) 
o 
Any areas concerning for stenosis should have velocities taken just proximal to narrowing and at the 
area narrowing to allow for velocity ratio calculation. 
 
§ 
Stent protocol 
§ 
Color Doppler Imaging 
• 
Single image of the proximal stent and the native inflow artery 
• 
Image(s) of the mid portion(s) of the stent  
• 
Single image of the distal stent including the native outflow artery 
§ 
Spectral Doppler 
• 
Common femoral artery (CFA) 
• 
Superficial femoral artery (SFA) 
• 
Inflow artery just proximal to the stent (PROX A) 
• 
Proximal stent (STENT P) 
• 
Mid stent segment(s) (STENT M) 
• 
Distal stent (STENT D) 
• 
Outflow artery just distal to stent (DIST A) 
• 
Any other areas concerning for stent associated stenosis 
§ 
Spectral Doppler analysis 
§ 
Systolic velocity ratio (Vr) = (maximum systolic velocity)/ (systolic velocity in the least proximal normal 
vessel) 
§ 
Vr should be calculated for all areas where there is concern for stenosis 

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§ 
Interpretation of NIV 
§ 
Restenosis is defined as velocity >300cm/s OR Vr>3.0 
§ 
Stent thrombosis (ST) defined as complete loss of any obtainable Doppler shift at area of concern 
 
Case Report Form Protocol: Patients will answer questions at each follow up visit elucidating adherence, as well as, 
addressing potential care received outside our hospital system. This form will be built into electronic medical record (EMR) 
as a hard stop. Clinical staff will interview patient and fill in the answers appropriately. The research team will then gather 
information from EMR and input to REDcap: 
1. Was antiplatelet medication stopped for any reason? 
2. How many antiplatelet medication doses were missed since last visit with us? 
3. Have you had any reintervention procedures on ipsilateral lower extremity? 
4. Have you had any amputation procedure on study lower extremity? 
5. Have you had any unexpected or prolonged bleeding events? 
6. Have you been hospitalized for unexpected or prolonged bleeding? 
7. Have you been diagnosed with stroke since last visit? 
8. Have you been diagnosed with heart attack since last visit? 
9. Have you been hospitalized for any reason? 
 
Data Collection and Storage 
 
We will be using a secure web based data entry system, REDcap. Research team will input all screening and baseline 
characteristics into this system. Procedural and platelet reactivity information will be entered by research team once 
available. Follow up information and case report form information will be entered once available. Limited access will be 
provided to this system. All data external to REDcap will be kept in the password-protected v-drive. The v-drive is 
already in use by the investigators and the division and has adequate space for the data. The investigators and clinical 
team currently have access electronic medical records. There will be no monetary funds or resources necessary to conduct 
the database maintenance. 
 
 
 
g. STATISTICAL EVALUATION  
 
Sample Size Calculation 
Patency for patients with HPR are derived from the two prospective studies, which use both primary patency and target 
limb revascularization as outcome. Since these are different, we have inflated the one-year primary patency rate to 40% 
for patients with HPR. Average one-year primary patency of femoropopliteal endovascular interventions is about 76%. 
Prevalence of HPR is about 25% based on local testing. Setting alpha at 0.05, beta at 0.2, and power at 0.8; we will need 29 
HPR patients to detect a difference in primary patency between HPR and non-HPR patients. Assuming 20% loss to follow 
up and 15% treatment failure (inability to perform angioplasty or stenting), we will have to test 179 patients. Therefore, 
we need a total of 358 patients. 
 
Statistical Analysis 
We will use intention to treat analysis. Our primary outcome is primary patency which is a dichotomous variable. We 
believe that Rutherford scale and smoking status may affect the outcome and a priori we plan to adjust for these 
variables. We will compare primary patency between our groups using proportional comparisons with chi squared or 
Fischer’s exact testing followed by adjusted logistic regression. Secondary analysis will be performed looking at time to 
event data Kaplan Meier Estimator with Cox proportional hazard ratios. Significance will be determined based on alpha 
less than 0.05. 
 
Secondary outcomes of one-year secondary patency and one-year amputation free survival are also categorical variables 
that will be analyzed in similar fashion. Secondary outcome of major adverse cardiovascular is a categorical variable and 
will be analyzed using simple descriptive statistics, univariate and multivariate logistic regression. Prevalence of HPR 
will be reported as a proportion and compared using chi squared testing. We will perform subgroup analysis on the stent 
group. Again, significant results will be reported based on alpha less than 0.05.  
 
h. SIGNIFICANCE AND CONCLUSON 
 
Preliminary studies of HPR in lower extremity arterial endovascular interventions report decreased patency in those who 
have HPR. Our study will be the first randomized study comparing treatment and testing for HPR in patients with lower 

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extremity arterial endovascular interventions. Results from this study can help reshape practice guidelines leading to 
improved management of lower extremity arterial disease. 
 
 

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Routine Testing for High on Treatment Platelet Reactivity in Patients After Lower Extremity Arterial Endovascular 
Interventions 
 
 
 
2/28/2019 
11 
 
Figure 1. Baseline characteristics 
 
Baseline Characteristics 
  
Treatment 
Arm n= 
Control 
Arm n= 
Age (mean, sd) 
  
  
Gender (% male) 
  
  
BMI (mean, sd) 
  
  
Race 
  
  
Caucasian (%) 
  
  
Black (%) 
  
  
Asian (%) 
  
  
Smoking 
  
  
current (%) 
  
  
prior (%) 
  
  
Hypertension (%) 
  
  
Hyperlipidemia (%) 
  
  
Diabetes (%) 
  
  
Dialysis (5) 
  
  
CAD (%) 
  
  
history of PCI (%) 
  
  
CHF (%) 
  
  
Rutherford Scale 
  
  
3 (%) 
  
  
4 (%) 
  
  
5 (%) 
  
  
Baseline 
Antiplatelet Use 
  
  
Clopidogrel (%) 
  
  
Ticagrelor (%) 
  
  
Aspirin (%) 
  
  
Baseline Statin Use 
(%) 
  
  
Proton Pump 
Inhibitor (%) 
  
  
Antidepressants (%) 
  
  
BMI=body mass index, CAD=coronary artery disease, 
PCI=percutaneous coronary intervention, CHF=congestive 
heart failure 
 
Figure 2. Outcomes 
Outcomes 
  
Treatment 
Arm n= 
Control 
Arm n= 
OR 
Adjusted 
OR 
p value 
Primary patency (%) 
  
  
  
  
  
Primary Assisted Patency (%) 
  
  
  
  
  
Secondary patency (%) 
  
  
  
  
  
Amputation (%) 
  
  
  
  
  
major 
  
  
  
  
  
minor 
  
  
  
  
  
Major Adverse Cardiovascular Events (%) 
  
  
  
  
  
VerifyNow PRU 
  
  
  
  
  
Pharmacogenetic Testing (%) 
  
  
  
  
  

Routine Testing for High on Treatment Platelet Reactivity in Patients After Lower Extremity Arterial Endovascular 
Interventions 
 
 
 
2/28/2019 
12 
 
UM 
  
  
  
  
  
EM 
  
  
  
  
  
IM 
  
  
  
  
  
PM