- Email: [email protected]
Relevance of Indications for CABG in Evaluating the Effect of Dual Antiplatelet Therapy
508
JACC VOL. 70, NO. 4, 2017
Letters
JULY 25, 2017:504–11
*Makoto Mori, MD Arnar Geirsson, MD
Relevance of Indications for CABG in Evaluating the Effect of Dual Antiplatelet Therapy
*Section of Cardiac Surgery Yale University School of Medicine BB204, 330 Cedar Street P.O. Box 208039 New Haven, Connecticut 06510
The secondary analysis of the FREEDOM (Future Revascularization Evaluation in Patients With Diabetes Mellitus: Optimal Management of Multivessel Disease) study data (1) leaves unanswered the question of whether patients with acute coronary syndromes
(ACS)
undergoing
coronary
E-mail: [email protected] http://dx.doi.org/10.1016/j.jacc.2017.03.615 Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Deepak L. Bhatt, MD, MPH, served as Guest Editor-in-Chief for this paper; and Faisal Bakaeen, MD, served as Guest Editor for this paper.
artery
bypass grafting [CABG] derive benefit from dual
REFERENCES
antiplatelet therapy (DAPT). However, the sub-
1. van Diepen S, Fuster V, Verma S, et al. Dual antiplatelet therapy versus aspirin monotherapy in diabetics with multivessel disease undergoing CABG: FREEDOM insights. J Am Coll Cardiol 2017;69:119–27.
group analysis stratified by the indications (ACS or stable angina) that demonstrated no significant benefit in either subgroup provides an additional insight into whether the ongoing distinction between ACS and stable ischemic heart disease in evaluating the effect of DAPT in patients postCABG is meaningful. This distinction by the clin-
2. Fox KA, Mehta SR, Peters R, et al. Benefits and risks of the combination of clopidogrel and aspirin in patients undergoing surgical revascularization for non-ST-elevation acute coronary syndrome: the CURE trial. Circulation 2004; 110:1202–8. 3. Levine GN, Bakaeen FG. Adding CABG to the dual antiplatelet salad. J Am Coll Cardiol 2017;69:128–30.
ical indication is largely derived from the historical
4. Gao G, Zheng Z, Pi Y, Lu B, Lu J, Hu S. Aspirin plus clopidogrel therapy increases early venous graft patency after coronary artery bypass surgery.
sequence of trials that initially demonstrated ben-
J Am Coll Cardiol 2010;56:1639–43.
efits of DAPT use in patients presenting with ACS with or without further percutaneous coronary
REPLY: Relevance of Indications for
intervention, culminating in the subgroup analysis
CABG in Evaluating the Effect of Dual
of the CABG cohort in the CURE (Clopidogrel in
Antiplatelet Therapy
Unstable Angina to Prevent Recurrent Ischemic Events) trial (2). Whether the presenting symptoms
We thank Drs. Mori and Geirsson for their interest in
would translate into clinical differences relevant to
our FREEDOM (Future Revascularization Evaluation
antiplatelet therapy following CABG, however, is
in Patients With Diabetes Mellitus: Optimal Manage-
questionable.
ment of Multivessel Disease) study secondary anal-
Potential benefits of DAPT in patients undergoing
ysis (1) examining aspirin monotherapy versus dual
CABG are derived from stabilization of existing pla-
antiplatelet therapy (DAPT) in diabetic patients with
que, improving vein graft patency, and continued
multivessel coronary artery bypass grafting (CABG).
protection of existing stents (3). Revascularization
We concur with the authors that the postulated ben-
with CABG alters the coronary perfusion architecture
efits of DAPT after CABG include stabilization of the
with
pa-
culprit lesion and preservation of both coronary stent
tients with ACS may be more susceptible to subse-
and vein graft patency. In addition, DAPT treatment
quent plaque rupture and stent thrombosis, the
can theoretically: 1) reduce the risk of acute coronary
event may not be as clinically significant in the
syndrome (ACS) recidivism in nonculprit arteries
bypassed coronary anatomy. On the other hand,
irrespective of bypass grafting; 2) augment platelet
the benefit of DAPT in preserving vein graft patency
inhibition in aspirin nonresponders; 3) reduce the
has been demonstrated in small trials (4), perhaps
risks of associated noncoronary conditions (e.g.,
implying that the myocardial territory perfused by
stroke in patients not receiving anticoagulation for
the vein grafts may be an important baseline
atrial fibrillation); and 4) mediate improved outcomes
parameter in evaluating outcomes of DAPT post-
through
CABG in the future. Clarification of the relevance of
decreased infarct size via ticagrelor erythrocyte
the indication would aid in future trial designs, as
adenosine reuptake inhibition) (2–4).
bypassing
grafts.
Therefore,
although
recent trials have enrolled mixed populations of ACS and non-ACS patients (4).
nonplatelet
receptor
interactions
(e.g.,
However, as the authors have astutely highlighted, the evidence supporting routine DAPT post-CABG for
JACC VOL. 70, NO. 4, 2017
Letters
JULY 25, 2017:504–11
*Makoto Mori, MD Arnar Geirsson, MD
Relevance of Indications for CABG in Evaluating the Effect of Dual Antiplatelet Therapy
*Section of Cardiac Surgery Yale University School of Medicine BB204, 330 Cedar Street P.O. Box 208039 New Haven, Connecticut 06510
The secondary analysis of the FREEDOM (Future Revascularization Evaluation in Patients With Diabetes Mellitus: Optimal Management of Multivessel Disease) study data (1) leaves unanswered the question of whether patients with acute coronary syndromes
(ACS)
undergoing
coronary
E-mail: [email protected] http://dx.doi.org/10.1016/j.jacc.2017.03.615 Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Deepak L. Bhatt, MD, MPH, served as Guest Editor-in-Chief for this paper; and Faisal Bakaeen, MD, served as Guest Editor for this paper.
artery
bypass grafting [CABG] derive benefit from dual
REFERENCES
antiplatelet therapy (DAPT). However, the sub-
1. van Diepen S, Fuster V, Verma S, et al. Dual antiplatelet therapy versus aspirin monotherapy in diabetics with multivessel disease undergoing CABG: FREEDOM insights. J Am Coll Cardiol 2017;69:119–27.
group analysis stratified by the indications (ACS or stable angina) that demonstrated no significant benefit in either subgroup provides an additional insight into whether the ongoing distinction between ACS and stable ischemic heart disease in evaluating the effect of DAPT in patients postCABG is meaningful. This distinction by the clin-
2. Fox KA, Mehta SR, Peters R, et al. Benefits and risks of the combination of clopidogrel and aspirin in patients undergoing surgical revascularization for non-ST-elevation acute coronary syndrome: the CURE trial. Circulation 2004; 110:1202–8. 3. Levine GN, Bakaeen FG. Adding CABG to the dual antiplatelet salad. J Am Coll Cardiol 2017;69:128–30.
ical indication is largely derived from the historical
4. Gao G, Zheng Z, Pi Y, Lu B, Lu J, Hu S. Aspirin plus clopidogrel therapy increases early venous graft patency after coronary artery bypass surgery.
sequence of trials that initially demonstrated ben-
J Am Coll Cardiol 2010;56:1639–43.
efits of DAPT use in patients presenting with ACS with or without further percutaneous coronary
REPLY: Relevance of Indications for
intervention, culminating in the subgroup analysis
CABG in Evaluating the Effect of Dual
of the CABG cohort in the CURE (Clopidogrel in
Antiplatelet Therapy
Unstable Angina to Prevent Recurrent Ischemic Events) trial (2). Whether the presenting symptoms
We thank Drs. Mori and Geirsson for their interest in
would translate into clinical differences relevant to
our FREEDOM (Future Revascularization Evaluation
antiplatelet therapy following CABG, however, is
in Patients With Diabetes Mellitus: Optimal Manage-
questionable.
ment of Multivessel Disease) study secondary anal-
Potential benefits of DAPT in patients undergoing
ysis (1) examining aspirin monotherapy versus dual
CABG are derived from stabilization of existing pla-
antiplatelet therapy (DAPT) in diabetic patients with
que, improving vein graft patency, and continued
multivessel coronary artery bypass grafting (CABG).
protection of existing stents (3). Revascularization
We concur with the authors that the postulated ben-
with CABG alters the coronary perfusion architecture
efits of DAPT after CABG include stabilization of the
with
pa-
culprit lesion and preservation of both coronary stent
tients with ACS may be more susceptible to subse-
and vein graft patency. In addition, DAPT treatment
quent plaque rupture and stent thrombosis, the
can theoretically: 1) reduce the risk of acute coronary
event may not be as clinically significant in the
syndrome (ACS) recidivism in nonculprit arteries
bypassed coronary anatomy. On the other hand,
irrespective of bypass grafting; 2) augment platelet
the benefit of DAPT in preserving vein graft patency
inhibition in aspirin nonresponders; 3) reduce the
has been demonstrated in small trials (4), perhaps
risks of associated noncoronary conditions (e.g.,
implying that the myocardial territory perfused by
stroke in patients not receiving anticoagulation for
the vein grafts may be an important baseline
atrial fibrillation); and 4) mediate improved outcomes
parameter in evaluating outcomes of DAPT post-
through
CABG in the future. Clarification of the relevance of
decreased infarct size via ticagrelor erythrocyte
the indication would aid in future trial designs, as
adenosine reuptake inhibition) (2–4).
bypassing
grafts.
Therefore,
although
recent trials have enrolled mixed populations of ACS and non-ACS patients (4).
nonplatelet
receptor
interactions
(e.g.,
However, as the authors have astutely highlighted, the evidence supporting routine DAPT post-CABG for