Introduction
Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12-inhibitor (clopidogrel, ticagrelor, or prasugrel) is recommended for up to 12 months
following percutaneous coronary intervention (PCI) with coronary drug-eluting stent
(DES) implantation [1]
[2]. Although DAPT reduces the risk of adverse cardiac events, it increases the risk
of bleeding, particularly in relation to surgical procedures [3]. As a consequence, the need for surgery or invasive procedures is a common reason
for DAPT interruption [4]. Surgery requiring interruption of DAPT may trigger adverse cardiac outcomes in
patients with recent DES implantation [5].
The risk of adverse cardiac events and bleeding complications differs depending on
the type of surgery [6]. Gastroscopy is associated with an upper gastrointestinal bleeding risk < 1 % [7] and guidelines recommend continuing DAPT throughout gastroscopy with or without
biopsy [7]. However, adherence to guidelines is inconsistent and DAPT is sometimes interrupted
for this minor invasive procedure [8], possibly because personal experience with bleeding complications may outweigh the
perceived benefits of guideline recommendations [8].
To the best of our knowledge, no study has hitherto examined the association between
DAPT strategy for PCI patients in relation to gastroscopy and the corresponding clinical
outcomes. Subsequently, the aim of the present study was to quantify (1) the rate
of gastroscopy within 12 months after PCI, (2) the rate of adverse cardiac events
and gastroscopy-related bleeding within 30 days of gastroscopy, and (3) the association
between antiplatelet therapy and these events.
Methods
The study was approved by The Danish Data Protection Agency (Ref: J.no. 2012-41-0164).
The Danish Health and Medicines Authority approved medical record reviews (Ref: 3-3013-284/1).
Registry studies do not require ethical approval in Denmark.
Study setting and participants
Patients receiving gastroscopy within 12 months of PCI were identified through Danish
medical registries. We conducted two nested case-control analyses within this cohort
by linking Danish medical registries. The nested case-control design allowed us to
retrieve data from the patients’ medical records and to report accurate information
with regard to the exact timing of DAPT in relation to gastroscopy with the same statistical
precision but without having to review all medical records of PCI patients with subsequent
gastroscopy.
The Danish Civil Registration System enabled us to collect information, linked at
the individual level, from national and regional administrative and medical registries
[9].
The Western Denmark Heart Registry (WDHR) collects patient and procedure information
on all coronary interventions performed at the three coronary intervention centers
in Western Denmark (Odense University Hospital, Aarhus University Hospital, and Aalborg
University Hospital). These centers cover a population of approximately three million
inhabitants corresponding to 55 % of the Danish population [10]. Our study population consisted of patients registered in the WDHR who were treated
with one or more DES between July 2005 and December 2011 (n = 22 654). For each patient,
the index PCI procedure was defined as the last PCI procedure performed during the
study period. We excluded patients treated medically, with balloon angioplasty, or
with bare metal stents only, since guidelines do not always stipulate 12 months of
DAPT treatment for these indications. For each patient, the first gastroscopy after
the index PCI was included.
The Danish National Patient Register (DNPR) contains data on all hospital contacts
since 1995, including dates of hospitalization, outpatients and discharge diagnosis/procedures
coded according to the 10th revision of the International Classification of Diseases
(ICD-10) [11]. We linked WDHR and DNPR data to identify patients who underwent gastroscopy with
or without biopsy (see Appendix) within 12 months after PCI.
Data were collected from three university hospitals and 18 community hospitals to
ensure a broad description of DAPT strategies and complications.
Adverse cardiac events were defined as cardiac death, myocardial infarction, or definite
stent thrombosis within 30 days following gastroscopy. Death was determined by using
the Civil Registration System while information on cause of death (cardiac or non-cardiac)
was retrieved from the Danish Registry of Causes of Death [12]. Cardiac death was defined as an evident cardiac death or death from unknown causes.
Myocardial infarction was identified in the DNPR and defined as an acute admission
plus an ICD-10 discharge code of I21 [11]. Information on definite stent thrombosis was obtained from the WDHR and defined
according to the Academic Research Consortium definition [13], and confirmed by review of medical records as described elsewhere [14]
[15]
[16].
For the nested case-control analysis addressing adverse cardiac events following gastroscopy,
cases were patients experiencing adverse cardiac events within 30 days following gastroscopy.
For each case, we identified four control patients who had a gastroscopy within 12
months after PCI, but experienced no adverse cardiac events. The controls were matched
by age (± 5 years), gender, and anticoagulant therapy with warfarin or phenprocoumon.
Information on use of these drugs was retrieved from the DNPR, which has collected
individual-level data on all prescription drugs sold in Danish pharmacies since 1994. The
drugs are recorded with Anatomic Therapeutic Codes (ATC) [17].
Gastroscopy-related bleeding complications were defined as hemostatic interventions
(adrenalin injection or electrocoagulation; ICD-10 codes are stated in the Appendix).
Hemostatic interventions served as a surrogate marker for gastroscopy-related bleeding
complications, since the DNPR contains specific codes for hemostatic intervention
and since gastroscopy-related bleeding complications in most instances will lead to
hemostatic intervention.
For the nested case-control study addressing gastroscopy-related bleeding events,
cases were patients receiving hemostatic intervention during or within 30 days following
the index gastroscopy. For each case, we identified two controls with gastroscopy
with biopsy, but without hemostatic intervention, to ensure a comparative risk of
bleeding. The controls were matched by age (± 10 years), gender, and anticoagulant
therapy (using ATC codes for warfarin and phenprocoumon). Compared to the first case-control
study, matching criteria (age) and number of controls were altered to allow for sufficient
matching.
One investigator (GE) systematically reviewed the medical records of the selected
cases and controls in the two nested case-control studies. We recorded treatment status
(on or off treatment) for aspirin and P2Y12-inhibitors during the period 30 days before and 30 days after gastroscopy.
In the nested case-control analyses, patients were categorized as receiving periprocedural
antiplatelet treatment when treatment was administered within 3 days before the gastroscopy.
DAPT was defined as treatment with both aspirin and a P2Y12-inhibitor. Single antiplatelet therapy (SAPT) was defined as treatment with only
one antiplatelet agent (aspirin or P2Y12-inhibitor), and interrupting DAPT was defined as no antiplatelet treatment within
3 days before gastroscopy. Periprocedural treatment was registered for aspirin and
P2Y12-inhibitors separately. Gastroscopies were defined as acute when performed within
3 days of acute admission.
Baseline data and covariates
For each patient, we computed comorbidity scores using the Charlson Comorbidity Index.
This index covers 19 major disease categories, including diabetes mellitus, heart
failure, cerebrovascular diseases, and cancer. This score is a weighted summary of
previous diagnoses, with weights based on the 1-year mortality associated with each
disease in the original Charlson dataset. The Charlson Comorbidity Index has recently
been validated in a cohort of acute coronary syndrome patients [18]. In this study, we used an adjusted Charlson Comorbidity Index score that did not
include diabetes and previous myocardial infarction since these two conditions were
considered separately.
Data on prescription medication not obtained from medical records were obtained from
the DNPR (see Appendix for ATC codes) [17]. Patients were considered to be on treatment when a prescription was redeemed within
100 days before gastroscopy. Further demographic and clinical data were collected
from the WDHR.
Since the risk of adverse cardiac events associated with DAPT discontinuation declines
with time after PCI [19], we also calculated time from index PCI to gastroscopy. We defined and categorized
gastroscopy as acute when performed within 3 days after acute admission.
Statistics
Baseline variables were presented as counts (%) apart from age, which was stated as
median (interquartile range; IQR (Q1 – Q3)). In the nested case-control studies, we
used conditional logistic regression to compute odds ratios for adverse cardiac events
and gastroscopy-related bleeding complications among the different periprocedural
antiplatelet strategies. All statistical analyses were performed using Stata 13 (Statacorp,
College Station, TX, United States).
Results
In a cohort of 22 654 patients treated with coronary DES implantation, we identified
1497 patients (6.6 %) who underwent gastroscopy within 12 months of PCI; of these,
1046 had gastroscopy with biopsy. Within 30 days after gastroscopy, 45 (3 %) patients
died. Thirteen of these suffered a cardiac death while nine had a myocardial infarction,
two of which were caused by stent thrombosis, yielding a total of 22 (1.5 %) adverse
cardiac events within the first 30 days following gastroscopy. Ninety-three patients
(6.2 %) received hemostatic intervention during gastroscopy ([Fig. 1]).
Fig. 1 Flowchart of patient selection for the nested case-control studies. a Adverse cardiac events nested case-control study. b Hemostatic interventions during gastroscopy nested case-control study. DES, drug-eluting
stent; PCI, percutaneous coronary intervention.
For the nested case-control studies, we collected information from the medical records
of 109 patients in the adverse cardiac events study and 279 patients in the hemostatic
intervention study. A single medical record (a control from the adverse cardiac events
nested case-control study) was not obtainable and was recorded as missing. The gastroscopies
were performed with a median time after PCI of 145 days (IQR, 60 – 249) ([Fig. 2]). P2Y12-inhibitors were clopidogrel for cases and controls, apart from four controls in the
gastroscopy related bleeding group on ticagrelor.
Fig. 2 Time from DES implantation to gastroscopy. The incidence (percentage) of gastroscopy
in PCI patients, categorized by time from PCI to gastroscopy.
Adverse cardiac events
In the nested case-control study focusing on adverse cardiac events, data were obtained
for 22 cases and 87 gastroscopy controls. The median time from PCI to gastroscopy
was 132 days (IQR, 33 – 248 days) for cases and 125 days (IQR, 48 – 224 days) for
controls. Demographic and clinical characteristics are provided in [Table 1].
Table 1
Demographic and clinical data for patients in the two nested case-control studies.
|
Adverse cardiac event study
|
Gastroscopy-related bleeding event study
|
|
Cases, n = 22
|
Controls, n = 87
|
Cases, n = 93
|
Controls, n = 186
|
|
Demographics
|
|
|
|
|
|
Age, median (IQR), years
|
73 (66 – 79)
|
73 (66 – 79)
|
72 (65 – 79)
|
71 (64 – 79)
|
|
Sex, male, no. (%)
|
12 (54.5)
|
48 (54.5)
|
71 (76.0)
|
142(76.0)
|
|
Smoking, no. (%)
|
5 (23.8)
|
16 (18.3)
|
25 (26.8)
|
43 (23.1)
|
|
Drug exposure, no (%)
|
|
|
|
|
|
Proton-pump inhibitors
|
9 (40.9)
|
38 (45.8)
|
32 (36.0)
|
96 (52.75)
|
|
Statins
|
10 (45.5)
|
57 (68.7)
|
69 (77.5)
|
138 (75.8)
|
|
Vitamin K-antagonists
|
3 (13.6)
|
14 (16.9)
|
8 (9.0)
|
17 (9.3)
|
|
NSAIDs
|
1 (4.5)
|
9 (10.9)
|
12 (13.5)
|
6 (3.3)
|
|
Cox 2-inhibitors
|
3 (13.6)
|
4 (4.8)
|
11 (12.4)
|
12 (6.6)
|
|
Oral glucocorticoids
|
2 (9.0)
|
12 (14.5)
|
11 (12.4)
|
15 (8.2)
|
|
Calcium antagonists
|
6 (27.3)
|
34 (41.0)
|
21 (23.6)
|
52 (28.6)
|
|
Beta blockers
|
12 (54.5)
|
51 (61.5)
|
60 (67.4)
|
136 (74.7)
|
|
SSRIs
|
2 (9.0)
|
11 (13.2)
|
12 (13.5)
|
30 (16.5)
|
|
Nitrates
|
4 (18.2)
|
14 (16.9)
|
18 (20.2)
|
33 (18.1)
|
|
Comorbidities
|
|
|
|
|
|
Hypertension, no. (%)
|
11 (61.1)
|
49 (63.6)
|
47 (58.8)
|
105 (66.5)
|
|
Hypercholesterolemia, no. (%)
|
7 (38.9)
|
46 (60.5)
|
46 (57.5)
|
105 (66.5)
|
|
Previous MI, no. (%)
|
3 (16.7)
|
21 (26.9)
|
20 (25.6)
|
33 (20.9)
|
|
Diabetes, no. (%)
|
2 (9.0)
|
15 (17.2)
|
15 (16.3)
|
28 (15.2)
|
|
Charlson Comorbidity Index,[1] mean
|
0.9
|
0.8
|
1.1
|
0.8
|
|
Lesion and procedural characteristics
|
|
|
|
|
|
Stent > 1, %
|
55
|
36
|
33
|
32
|
|
Stent length > 20 mm, %
|
62.1
|
45.2
|
48.6
|
49.3
|
|
PCI indication ACS, no. (%)
|
13 (59)
|
40 (45)
|
59 (63)
|
94 (51)
|
|
PCI indication SAP, no. (%)
|
8 (36)
|
44 (50)
|
31 (33)
|
87 (47)
|
|
Indication[2] UGIH, no. (%)
|
17 (77)
|
31 (35)
|
93 (100)
|
48 (26)
|
|
Indication[2] dyspepsia, no. (%)
|
5 (23)
|
31 (35)
|
0
|
25 (13)
|
|
Indication[2] anemia, no. (%)
|
0
|
24 (27)
|
0
|
111 (60)
|
IQR, interquartile range; NSAIDs, nonsteroidal anti-inflammatory drugs; Cox, cyclooxygenase;
SSRIs, selective serotonin re-uptake inhibitors; MI, myocardial infarction; PCI, percutaneous
coronary intervention; ACS, acute coronary syndrome; SAP, stable angina pectoris;
UGIH, upper gastrointestinal hemorrhage.
1 Modified score, see Methods section.
2 Indication for gastroscopy.
In this nested case-control cohort including 109 patients, 91 % received aspirin and
97 % received a P2Y12-inhibitor before gastroscopy. Treatment with these drugs was interrupted > 3 days
before gastroscopy for 24 % of the patients taking aspirin and for 23 % of patients
taking P2Y12-inhibitors. Aspirin or a P2Y12-inhibitor treatment was resumed in 9 % and 14 % of patients, respectively, within
7 days following gastroscopy.
Among patients with an adverse cardiac event, 9 % did not receive any antithrombotic
treatment at the time of gastroscopy and 77 % received DAPT ([Table 2]). The risk of cardiac events was 3.46 times higher among patients not receiving
antiplatelet therapy compared to those receiving DAPT (95 % confidence interval (CI)
0.49 – 24.71). Single antiplatelet therapy (SAPT) was not associated with an increased
risk compared to DAPT therapy (odds ratio (OR) 0.65, 95 %CI 0.17 – 2.47).
Table 2
Periprocedural antiplatelet treatment in patients included in the nested case-control
studies.
|
Group
|
DAPT
|
Only a P2Y12-inhibitor
|
Only aspirin
|
No treatment
|
|
Adverse cardiac event study
|
|
|
|
|
|
Cases (N = 22), no. (%)
|
17 (77)
|
1 (5)
|
2 (9)
|
2 (9)
|
|
Controls (N = 87), no. (%)
|
67 (77)
|
12 (14)
|
6 (7)
|
2 (2)
|
|
Gastroscopy-related bleeding event study
|
|
|
|
|
|
Cases (N = 93), no. (%)
|
79 (85)
|
5 (5.5)
|
5 (5.5)
|
4 (4)
|
|
Controls (N = 186), no. (%)
|
138 (74)
|
18 (10)
|
19 (10)
|
11 (6)
|
DAPT, dual antiplatelet therapy.
Gastroscopy-related bleeding
In the nested case-control study of gastroscopy-related bleeding, we obtained data
from 93 cases receiving a hemostatic intervention and 186 controls without such intervention.
The median time from PCI to gastroscopy was 114 days (IQR, 52 – 224 days) for cases
and 166 days (IQR, 70 – 267 days) for controls. Demographic and clinical characteristics
are presented in [Table1] and periprocedural treatment in [Table 2].
In this nested case-control cohort of 279 patients, 92 % received aspirin and 94 %
a P2Y12-inhibitor before gastroscopy. Treatment with these drugs was interrupted > 3 days
before gastroscopy for 37 % of the patients taking aspirin and for 33 % of the patients
taking P2Y12-inhibitors. Aspirin or P2Y12-inhibitor treatment was resumed in 15 % and 20 % of patients, respectively, within
7 days following gastroscopy.
A total of 1046 patients had gastroscopy with biopsy. Using hemostatic intervention
as a surrogate marker for bleeding complications, none of these 1046 patients had
complications in relation to the biopsies.
All 93 cases who received a hemostatic intervention had suffered spontaneous bleeding
before gastroscopy. Of these, 91 hemostatic interventions were performed during index
gastroscopy and two at a new gastroscopy within 30 days. Thus, none of the hemostatic
interventions were caused by gastroscopy-related bleeding complications due to biopsy.
Gastroscopy was performed acutely in 84 cases (90 %) while the remaining cases had
gastroscopy performed electively. In the control group, 129 gastroscopies (69 %) were
performed electively.
None of the controls had a hemostatic intervention within 30 days after gastroscopy.
Among cases, 85 % received DAPT, 11 % received single antiplatelet therapy (SAPT)
and 4 % received no periprocedural antiplatelet treatment. After initial gastroscopy,
13 cases and two controls had re-gastroscopy on suspicion of active bleeding during
admission; however, no active bleeding was found.
Discussion
In this population-based cohort, gastroscopy was required in 6.6 % of patients within
the first year after PCI with DES. Of these, 1.5 % suffered an adverse cardiac event
and 6.2 % had a hemostatic intervention within 30 days following gastroscopy. Interrupting
DAPT seemed to be associated with an increased risk of cardiac events in our cohort.
Importantly, continuation of a single antiplatelet agent in relation to gastroscopy
had the same protective effect against adverse cardiac events as DAPT. Review of the
medical journals revealed that none of the cases in need of a hemostatic intervention
had the intervention due to complications related to gastroscopy regardless of their
antiplatelet therapy, and none of the controls required hemostatic intervention after
biopsy, therefore SAPT or DAPT should thus not be a contraindication for hemostatic
intervention or biopsy during gastroscopy.
Adverse cardiac events related to gastroscopy
The adverse cardiac event rate of 1.5 % within 30 days following gastroscopy in our
study population should be considered in the light of a reported event rate of 5 %
within 9 months among patients treated with DES [16]. There are limited reports with regard to adverse cardiac events following gastroscopy
[20]
[21]
[22]
[23] and we can only extrapolate from settings not involving procedures following PCI.
We speculate that the explanation for the higher rate of adverse cardiac events observed
here, apart from pre-existing cardiovascular disease, may be hemodynamic instability
or a pro-thrombotic state related to bleeding events due to hypovolemia. In our cohort,
43 % of gastroscopies were performed due to clinically manifest, or suspicion of,
upper gastrointestinal bleeding. Also, the indication for gastroscopy, i. e. confirmed
or suspected upper gastrointestinal bleeding, may be associated with interruption
of antiplatelet treatment. We found a high compliance rate of 77 % for DAPT during
gastroscopy for both cases and controls, resulting in very little information contrast
rendering the confidence interval broad and the odds ratio without a traditional statistical
significance of 5 %. However, a relative risk of 3.46 for an adverse cardiac event
if the patients do not receive any DAPT during gastroscopy is not negligible.
The Standards of Practice Committee of the American Society for Gastrointestinal Endoscopy
(ASGE) recommends continuation of DAPT throughout gastroscopy in these patients [7]. A recently reported survey among endoscopists noted that only 30 % of responding
endoscopists adhered to the ASGE guidelines on antiplatelet therapy in relation to
endoscopic procedures. Among respondents, 26 % withheld all antiplatelet therapy before
engaging in any patient procedure, possible exposing the patients to an increased
ischemic risk [8]. DAPT interruption in patients with DES is a strong predictor of ischemic events
[5]
[24]. However, while discontinuation of both aspirin and clopidogrel, one of the available
P2Y12-inhibitors, was associated with stent thrombosis, continuation of aspirin and discontinuation
of clopidogrel was not [24]
[25]. Accordingly, we found that reduction in periprocedural DAPT to a single antiplatelet
agent, but with no difference between aspirin and clopidogrel, yielded the same protection
against cardiac events as DAPT. Consequently, reduction in DAPT to aspirin or clopidogrel
alone seems a safe choice in patients on DAPT who await gastroscopy on the suspicion
of upper gastrointestinal bleeding.
Risk of gastroscopy-related bleeding in patients with DES implantation
Most importantly, we found that neither cases nor controls in the two nested case-control
studies had bleeding episodes as a complication to gastroscopy with or without biopsy
despite the high rate of periprocedural DAPT. These data strongly suggest that both
elective and acute gastroscopy can be performed safely in patients receiving DAPT,
although short intermittent reduction to a single antiplatelet agent also seems safe
with regard to adverse cardiac events. Aspirin is known to injure the gastric mucosa
while clopidogrel does not [26]. In the randomized, blinded CAPRIE study of clopidogrel versus aspirin in patients
at risk of ischemic events, gastrointestinal bleeding was significantly less frequent
in patients treated with clopidogrel 75 mg daily vs. aspirin 325 mg daily (0.52 %
vs. 0.72 %) [27] while a prospective, randomized study involving 630 biopsies in healthy volunteers
found no clinically important bleeding regardless of treatment with aspirin or clopidogrel
[28]. The added effect of clopidogrel and aspirin further increases the relative risk
of bleeding up to 50 %. These studies thus indicate that aspirin and clopidogrel have
very similar risks of gastrointestinal bleeding when used separately while the combined
use increases the risk of bleeding. In this setting, it is important to note that
our data support the recommendations that DAPT should not be routinely interrupted
before gastroscopy and also that hemostatic intervention or biopsy can be performed
safely in patients receiving aspirin and/or a P2Y12-inhibitor within 3 days before gastroscopy.
Collective strategy for patients undergoing gastroscopy after PCI
The optimal treatment strategy for a patient with gastrointestinal bleeding, who has
recently undergone a PCI procedure, is complex with competing risks of rebleeding
and adverse cardiac events. The recently updated European Joint Task Force Guidelines
on Non-cardiac Surgery [6] recommends continued DAPT at the time of gastroscopy, but acknowledges the absence
of randomized clinical trial data supporting this and that clinical circumstances
with bleeding complications may necessitate suspension of either one or both antiplatelet
agents [6].
In our study, we included both acute and elective gastroscopies to cover the diversity
among patients needing a gastroscopy. This also means that, in some patients, there
was no time to reduce DAPT. Despite this, no complications were observed which were
directly related to hemostatic intervention or biopsy, which falls in line with the
guidelines. Nevertheless, the challenge is patients who are under suspicion for upper
gastrointestinal bleeding while on DAPT, leading to gastroscopy.
In our study, the majority of cases had acute gastroscopy and hence there was no opportunity
to plan a treatment strategy. Even so, no cases had further bleeding leading to hemostatic
intervention after the initial gastroscopy. From the potential decreased bleeding
risk by reduction from DAPT to a single antiplatelet agent, and based on our finding
of a low risk of adverse cardiac events in patients treated with a single antiplatelet
agent, we advocate a single antiplatelet strategy for a shorter period in patients
with a suspected acute bleeding episode. The clinical situation, the comorbidities,
and the risk stratification by gastroscopy, will allow the treating physician to judge
if, and when, DAPT can be re-initiated. Among elective patients, our data indicate
that it is safe to either continue DAPT or reduce DAPT to a single antiplatelet agent
3 days before gastroscopy. The combined evidence from several studies including the
current study indicate that it is safe to reduce DAPT to SAPT, whereas stopping both
antiplatelet agents is associated with an increased risk of adverse cardiac events
[29]
[30]
[31]. In Denmark, the guidelines only stipulate proton pump inhibitor (PPI) treatment
for patients on DAPT, if the patients have risk factors for ulcer present at the time
of PCI. The proportions of patients on PPI treatment were relatively low. Since 6.6 %
of DES-treated patients undergo gastroscopy within 12 months and since PPIs reduce
the risk of upper gastrointestinal bleeding [32], one may consider making PPI treatment the standard of care in patients receiving
DAPT.
Strengths and limitations
The strength of our study is its combined evaluation of both 30-day risk of adverse
cardiac events and 30-day bleeding risk following gastroscopy. We were able to identify
the patients who suffered adverse cardiac events using Danish registries with documented
validity [10]. In addition, individual patient medical records were thoroughly examined to extract
specific information about procedures, outcomes, and medical therapy. Nevertheless,
separating adverse cardiac events from bleeding events is not straightforward since
an important interaction between the two types of events is likely as major bleeding
may lead to myocardial infarction. Major bleeding, compared to minor bleeding, is
associated with a higher risk of interrupting both aspirin and P2Y12-inhibitor treatment and of pro-thrombotic states, blood transfusions, and hemodynamic
instability, all of which may affect the risk of adverse cardiac events. Our risk
estimates were imprecise with broad confidence intervals since compliance to DAPT
was relatively high and event rates relatively low despite evaluating all 1497 gastroscopies
in a cohort of 22 654 PCI patients. Our study was restricted to patients treated with
DES, which represents more than 90 % of all patients in the WDHR during the study
period. DAPT is usually discontinued 3 – 5 days before a surgical procedure. During
this interruption, patients may suffer an adverse cardiac event before the gastroscopy
with consequent cancellation of the procedure. Such incidents could not be detected
with our study design. Evaluating the patient’s record gave us information on indication
for gastroscopy. In the reoperation for bleeding study, the indication for cases was
more often upper gastrointestinal hemorrhage compared to controls; however, we cannot
rule out the possibility that this is due to information bias as a patient in need
of a hemostatic intervention could more likely be classified as having upper gastrointestinal
hemorrhage as indication whereas the indication anemia might be used if there is no
active bleeding.
Conclusions
Gastroscopy is common within the first year after stent implantation, and management
of the PCI-related DAPT represents a clinical challenge. We observed a relatively
high risk of adverse cardiac events and hemostatic interventions. A single antiplatelet
strategy may reduce the need for hemostatic intervention while, in accordance with
previous studies, interruption of both antiplatelet agents seems associated with adverse
cardiac events. A single antiplatelet strategy does thus seem recommendable in patients
suspected of having upper gastrointestinal bleeding.
Appendix
Table 3
ICD 10 codes used.
|
ICD 10 code
|
|
Gastroscopy with or without biopsy
|
KUJD02, KUJD05
|
|
Hemostatic interventions (adrenalin injection or electrocoagulation)
|
KJDA32, KJDA 35, KJDH18, and KJDH15
|
Table 4
ATC codes for redeemed prescription medications within 100 days before surgery.
|
Medication
|
ATC code
|
|
Vitamin K antagonists
|
B01AA03, B01AA04
|
|
Statins
|
C10AA01-2, C10AA04-5
|
|
Proton pump inhibitors
|
A02BC01, A02BC02, A02BC03, A02BC04, A02BC05
|
|
Calcium channel blockers
|
C08CA01-3, C08CA05, C08CA08, C08CA09, C08CA13, C08CX01, C08DA, C08DB01
|
|
Cyclooxygenase-2 selective inhibitors
|
M01AH, M01AB05, M01AB55, M01AB08, M01AC06, M01AX01
|
|
Nonselective nonsteroidal anti-inflammatory drugs
|
M01AB01, M01AC01, M01AE01, M01AE51, M01AE02, M01AE03, M01AE53, M01AE14, M01AG02
|
|
Systemic glucocorticoids
|
H02AB
|
|
Beta blockers
|
C07
|
|
Anti-depressives (SSRIs)
|
N06AB04, N06AB10, N06AB03, N06AB05, N06AB06
|
|
Nitrates
|
C01DA02
|
|
Low molecular weight heparin (LMWH)
|
B01AB05, B01AB10, B01AB04
|
SSRIs, selective serotonin re-uptake inhibitors
