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the online version of this article ( doi:10.1007/s40119 - 015 - 0050 - 2 ) contains supplementary material , which is available to authorized users .
current guidelines call for lifelong aspirin ( acetylsalicylic acid ; asa ) with consideration of up to 6  months of clopidogrel following transcatheter aortic valve replacement ( tavr ) .
recently , small studies have questioned the necessity of dual antiplatelet therapy ( dapt ) following the procedure .
furthermore , many patients receiving tavr have a pre - existing indication for oral anticoagulation ( oac ) , most commonly atrial fibrillation ( af )
. to date , there have been little data formally addressing the optimal combination of antiplatelet and anticoagulant medications after tavr , particularly in patients with an indication for oac .
a 2012 expert consensus document supported by the american college of cardiology ( acc ) and society of thoracic surgeons ( sts ) suggests treating these patients with asa and an anticoagulant , omitting clopidogrel .
the 2014 acc / american heart association ( aha ) valvular disease guidelines give a iib recommendation for 6  months of treatment with asa and clopidogrel after tavr , but do not comment on patients with an indication for anticoagulation .
current european society of cardiology ( esc ) guidelines state that in tavr patients with af , a single antiplatelet combined with an anticoagulant is generally used but treatment decisions should be made based on the perceived bleeding risk of an individual patient .
actual treatment patterns in clinical practice are unknown and are likely to vary by physician and institution .
therefore , we assessed the current practice of antithrombotic treatment following tavr at a single , large academic center .
we performed manual chart review of all patients undergoing tavr from april 2009 through march 2014 at brigham and women s hospital in boston , ma , usa . pre - tavr antithrombotic regimens were obtained from admission medication reconciliations or prior clinic notes when possible .
post - procedural medications were obtained from the hospital s electronic medication administration log and patient discharge summaries .
all procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation ( institutional and national ) and with the helsinki declaration of 1964 , as revised in 2013 .
of 255 total patients ( mean age 81  years , 48% female ) , 169 ( 66% ) had transfemoral , 44 ( 17% ) had transapical , and 42 ( 16% ) had an alternative access site tavr ( table  1 ) .
one hundred and thirty - one ( 51% ) patients had an indication for oac pre - tavr , of which 122 ( 48% ) had af and chads2 ( congestive heart failure , hypertension , age , diabetes , stroke ) score > 1 , 6 ( 2% ) had a history of deep vein thrombosis / pulmonary embolism , and 3 ( 1% ) had other indications . of patients with an indication for oac , 92 ( 70% )
were on oac prior to the procedure , the majority ( 88% ) of whom were treated with warfarin .
twenty - nine ( 11% ) of the total cohort were on dapt prior to the procedure ( most for recent coronary stenting ) and 5 ( 2% ) were receiving triple therapy with two antiplatelet agents and an anticoagulant .
complete baseline and discharge antithrombotic use is shown in table  2.table  1baseline characteristicscharacteristicvalueage , years80.6    9.77bmi , km / m 
 27.3    6.66white94.9male51.8hypertension90.2diabetes39.6atrial fibrillation or flutter48.2  permanent38.2  paroxysmal45.5  n / a16.3chads2 score3.29    1.05nyha class iii / iv93egfr , ml / min/1.73  m 
 57.8    29.5dialysis3.1mi21.6pci29.0cabg36.1peripheral arterial disease22.0cerebrovascular disease13.3chronic lung disease40.8dvt
/ pe9.0gi bleeding14.9hemoglobin , g / dl11.1    1.78platelets , k/l201.7    82.6lvef , % 53.8    14.68aortic valve area , cm 
 0.66    0.17aortic valve peak velocity , m / sec4.29    0.63moderate - severe mr39.3transfemoral66.3transapical17.3other valve access site16.4values are mean    standard deviation or percentage 
 bmi body mass index , cabg coronary artery bypass grafting , chads 
 2 congestive heart failure , hypertension , age , diabetes , stroke , dvt / pe deep vein thrombosis / pulmonary embolism , egfr estimated glomerular filtration rate , gi gastrointestinal , lvef left ventricular ejection fraction , mi myocardial infarction , mr mitral regurgitation , n / a not available , nyha new york heart association , pci percutaneous coronary interventiontable  2admission and discharge antithrombotic regimens in patients undergoing transcatheter aortic valve replacementadmission antithrombotic regimendischarge antithrombotic regimensapt 
 dapt 
 oacsapt  +  oactriple 

diedtotalnone416041530sapt77801603104dapt121041229oac012217233sapt  +  oac050433354triple0101305total121222891515255 
 asa aspirin ( acetylsalicylic acid ) , dapt dual antiplatelet therapy , oac oral anticoagulation , sapt single antiplatelet therapy 
 sapt  =  asa or p2y12 antagonist 
 dapt  =  asa  +  p2y12 antagonist 
 triple  =  asa  +  p2y12 antagonist  +  oac baseline characteristics values are mean    standard deviation or percentage 
 bmi body mass index , cabg coronary artery bypass grafting , chads 
 2 congestive heart failure , hypertension , age , diabetes , stroke , dvt / pe deep vein thrombosis / pulmonary embolism , egfr estimated glomerular filtration rate , gi gastrointestinal , lvef left ventricular ejection fraction , mi myocardial infarction , mr mitral regurgitation , n / a not available , nyha new york heart association , pci percutaneous coronary intervention admission and discharge antithrombotic regimens in patients undergoing transcatheter aortic valve replacement 
 asa aspirin ( acetylsalicylic acid ) , dapt dual antiplatelet therapy , oac oral anticoagulation , sapt single antiplatelet therapy 
 sapt  =  asa or p2y12 antagonist 
 dapt  =  asa  +  p2y12 antagonist 
 triple  =  asa  +  p2y12 antagonist  +  oac all patients had oac held prior to the procedure and only 12 ( 13% ) patients on baseline oac were bridged with a parental anticoagulant prior to tavr . there were 155 patients ( 65% ) who had an indication for oac post - tavr ( including 19 with new onset af ) , and of these 77 ( 50% ) were bridged with parental anticoagulation after the procedure . of the 145 patients with an indication for oac who survived the initial hospitalization , 106 ( 73% ) were discharged on an antithrombotic regimen that included an anticoagulant .
of the 16 surviving patients with new onset af , 11 ( 69% ) were newly started on oac after tavr . in the total cohort
there were 15 deaths , 13 strokes ( 10 ischemic , 2 hemorrhagic , and 1 unspecified ) and 29 major bleeding events prior to discharge .
seven out of 13 patients with in - hospital stroke ( 5 ischemic ) had longstanding af . of the 5  patients with ischemic stroke , three were not on baseline oac and two had oac held without bridging prior to the procedure .
of 106 patients discharged on oac , 89 ( 84% ) were treated with asa  +  oac .
the most common discharge regimen for the 95 surviving patients without an indication for anticoagulation was dapt ( 93% ) with only 7 ( 7% ) receiving asa or clopidogrel alone .
in addition , the small number of events and lack of long - term follow - up precluded our ability to relate treatment medications with outcomes .
in addition , the small number of events and lack of long - term follow - up precluded our ability to relate treatment medications with outcomes .
in conclusion , at our institution , post - procedural antithrombotic regimens in patients receiving tavr are highly variable . nearly two - thirds of patients had an indication for oac post - tavr . for patients with an indication for anticoagulation ,
treating physicians tended ( 84% ) to follow consensus guidelines that suggest a regimen of asa  +  oac following the procedure .
overall , dapt remains the most frequent antithrombotic regimen at discharge , although 7% of patients were treated with a single antiplatelet agent alone .
an analysis of the german aortic valve registry ( gary ) found similar results with 66% of patients discharged on dapt and 27% discharged on an anticoagulant .
this study showed a higher rate of triple therapy with 16% of total patients discharged on dapt plus an anticoagulant . whether these regimens truly represent the optimal balance between bleeding and thrombosis following tavr , particularly in patients at high risk for adverse events like those with af ,
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all procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation ( institutional and national ) and with the helsinki declaration of 1964 , as revised in 2013 .
introductionthe aim of this study was to describe peri - procedural antithrombotic use in patients undergoing transcatheter aortic valve replacement ( tavr ) at a single academic medical center.methodsretrospective collection of antiplatelet and anticoagulant use during the index hospitalization for all patients undergoing tavr at our institution from april 2009 through march 2014.resultsof a total of 255 patients undergoing the procedure , 132 ( 51% ) had an indication for anticoagulation pre - tavr and 92 ( 70% of those with an indication ) were on treatment . on discharge , 106 patients ( 44% of total surviving to discharge , 73% of those surviving with an indication for anticoagulation ) were treated with oral anticoagulation . of these patients , 
 89 ( 84% ) were discharged on aspirin and an oral anticoagulant without clopidogrel . only 122 ( 51% of total patients ) were discharged on the regimen of aspirin and clopidogrel alone.conclusionperi-procedural antithrombotic regimens vary greatly following tavr . 
 more than half of patients have an indication for anticoagulation following the procedure . 
 most patients at our institution who require anticoagulation are discharged on aspirin and an oral anticoagulant , though the optimal regimen requires further investigation.electronic supplementary materialthe online version of this article ( doi:10.1007/s40119 - 015 - 0050 - 2 ) contains supplementary material , which is available to authorized users .