Abstract
Background
The safety and efficacy of everolimus eluting bioabsorbable vascular scaffold (BVS) in the management of “ST” segment elevation myocardial infarction (STEMI) are yet to be established.
Aims
To evaluate immediate and short term safety and efficacy of the everolimus-eluting ABSORB BVS compared with non BVS drug eluting stent (DES) in patients with STEMI.
Methods
From December 2013 to December 2014, 220 patients with STEMI were included in this study. Among them, 35 patients treated with BVS were compared with a control group composed of 180 patients who underwent non BVS DES implantation in the same time period. The incidence of major adverse cardiac events (MACE: stent thrombosis: death, non-fatal myocardial infarction, or target vessel/lesion revascularization) before discharge and up to six months was evaluated.
Results
1 vessel disease was more frequent whereas, 2 and 3 vessel disease was less frequent in BVS group. Procedural characteristics were also similar between groups, except for the use of post dilation (p = 0.04). Procedural success, in-hospital, and up to six-month MACE rates were similar between both groups. Definite or probable stent thrombosis did not occur (according to the ARC criteria) in BVS patients, though two patients during the index admission and another two patients in the first month after DES implantation had stent thrombosis.
Conclusion
The use of the ABSORB BVS for STEMI is feasible and associated with good procedural safety, and angiographic success rate.
1
Introduction
Primary percutaneous coronary intervention (PPCI) is now becoming the standard of care in the management of acute ‘ST’ segment elevation myocardial infarction (STEMI) and clearly superior to thrombolysis . The evolution of bare metal stent (BMS) to drug eluting stent (DES) and especially new second generation DES has significantly improved the outcome in STEMI patients . The everolimus DES has been shown to have superior clinical outcome than first generation DES and to be comparable to other second generation DES . They are associated with very low risk for stent thrombosis . The implantation of metal device in both BMS and DES has some limitation in the form of permanent caging and alteration of vasomotion in coronary artery, side branch jailing and possibility of future surgical revascularization of stented segment . Although DES inhibits neointimal proliferation, antiproliferative drug elution has been shown to interfere with the vascular healing and leads to late stent thrombosis or malapposition . The everolimus eluting biabsorbable vascular scaffold (BVS) has been designed to overcome many of these limitations and several studies of stable coronary artery disease have shown excellent results . Though the use of BVS in high thrombogenic milieu of STEMI is recently investigated in randomized trial, there are only limited data of using BVS in this clinical condition .
From these lacunae of knowledge, we conducted this single center observational study to investigate the feasibility, and acute and short term outcomes following implantation of single or multiple BVS compared to non BVS DES in the management of STEMI.
2
Methods
2.1
Study design
It was a prospective, non randomized comparative single center observational study conducted in a tertiary care private hospital between December, 2013 and December, 2014. The study design was approved by the institute ethics committee. Written consent was taken from all patients included in this study.
2.2
Study patients
220 consecutive patients who presented with STEMI were included in this study.
2.2.1
Eligibility criteria
2.2.1.1
Inclusion criteria
1. All patients with STEMI who presented within 12 h duration and who presented within 12–24 h duration with ongoing chest pain;
2. Received PPCI with ABSORB BVS (ABSORB; Abbott Vascular, Santa Clara, CA, USA) or non BVS newer second generation DES; and
3. Signed written informed consent.
2.2.1.2
Exclusion criteria
1. Patients with Killip class IV
2. Associated other severe co-morbidities with probable survival less than 1 year;
3. Contraindication for prolonged dual antiplatelet therapy (DAPT).
4. Patients who received bare metal stents for PPCI.
2.3
Study device and procedure
The ABSORB device consists of a polymer backbone of poly-L-lactide coated with a thin layer of a 1:1 mixture of poly-D,L-lactide polymer . The antiproliferative agent everolimus is integrated in this matrix in a dose of 100 mg of everolimus/cm 2 of scaffold. This study includes consecutive patients in a non-randomized design and BVS use was decided by size of index vessel and length of the lesion along with financial background of the patients. In an affordable patient with a reference vessel diameter compatible with the use of a 2.5, 3.0 or 3.5 mm BVS, were treated with BVS and remaining control group patients received implantation of newer second generation DES. Except for BVS utilization, all procedures were performed according to standard techniques. The final interventional strategy, use of GP IIb/IIIa inhibitors and post-dilatation were left to the operator’s discretion. Aspiration thrombectomy was used in all cases of complete thrombotic vessel occlusion. Weight-adjusted heparin was administered with a target activated clotting time of 250 s, and target lesions were treated using standard interventional techniques. After giving standard loading, dual antiplatelet therapy (DAPT) with aspirin 150 mg plus clopidogrel, prasugrel or ticagrelor was prescribed in all patients for at least 12 months. “Marker to marker” overlap strategy was used in cases where BVS overlapping PCI was performed.
2.4
Study endpoints
The primary endpoint of the study was procedural success, defined as BVS implantation at the “culprit” lesion site with less than 30% final stenosis and thrombolysis in myocardial infarction (TIMI) 3 flow without in-hospital major adverse cardiovascular events (MACE). The history regarding MACE including death (cardiac & non cardiac), non-fatal myocardial infarction (with or without ST-segment elevation), or need for repeat revascularization (target lesion/vessel revascularization) was collected at discharge and at monthly interval during follow-up by pre determined questionnaires and investigations were performed where necessary. The definition of myocardial infarction and stent thrombosis before and after the index procedure was based on standard published criteria .
Furthermore, we evaluated the occurrence BVS restenosis, defined as a diameter stenosis ≥ 50% within the scaffolded segment or 5 mm proximal or distal to the scaffolded segment by diagnostic coronary angiogram when it was done for symptomatic patients during follow-up. Clinical data were collected by hospital visit or telephone contact at monthly interval post procedure.
2.5
Statistical analysis
Data are presented as mean ± standard deviation (SD) or number (%). Continuous variables were compared with the Student’s t-test or analysis of variance, while discrete variables were compared with the Chi square tests. Any P value less than 0.05 was considered as statistically significant.
2
Methods
2.1
Study design
It was a prospective, non randomized comparative single center observational study conducted in a tertiary care private hospital between December, 2013 and December, 2014. The study design was approved by the institute ethics committee. Written consent was taken from all patients included in this study.
2.2
Study patients
220 consecutive patients who presented with STEMI were included in this study.
2.2.1
Eligibility criteria
2.2.1.1
Inclusion criteria
1. All patients with STEMI who presented within 12 h duration and who presented within 12–24 h duration with ongoing chest pain;
2. Received PPCI with ABSORB BVS (ABSORB; Abbott Vascular, Santa Clara, CA, USA) or non BVS newer second generation DES; and
3. Signed written informed consent.
2.2.1.2
Exclusion criteria
1. Patients with Killip class IV
2. Associated other severe co-morbidities with probable survival less than 1 year;
3. Contraindication for prolonged dual antiplatelet therapy (DAPT).
4. Patients who received bare metal stents for PPCI.
2.3
Study device and procedure
The ABSORB device consists of a polymer backbone of poly-L-lactide coated with a thin layer of a 1:1 mixture of poly-D,L-lactide polymer . The antiproliferative agent everolimus is integrated in this matrix in a dose of 100 mg of everolimus/cm 2 of scaffold. This study includes consecutive patients in a non-randomized design and BVS use was decided by size of index vessel and length of the lesion along with financial background of the patients. In an affordable patient with a reference vessel diameter compatible with the use of a 2.5, 3.0 or 3.5 mm BVS, were treated with BVS and remaining control group patients received implantation of newer second generation DES. Except for BVS utilization, all procedures were performed according to standard techniques. The final interventional strategy, use of GP IIb/IIIa inhibitors and post-dilatation were left to the operator’s discretion. Aspiration thrombectomy was used in all cases of complete thrombotic vessel occlusion. Weight-adjusted heparin was administered with a target activated clotting time of 250 s, and target lesions were treated using standard interventional techniques. After giving standard loading, dual antiplatelet therapy (DAPT) with aspirin 150 mg plus clopidogrel, prasugrel or ticagrelor was prescribed in all patients for at least 12 months. “Marker to marker” overlap strategy was used in cases where BVS overlapping PCI was performed.
2.4
Study endpoints
The primary endpoint of the study was procedural success, defined as BVS implantation at the “culprit” lesion site with less than 30% final stenosis and thrombolysis in myocardial infarction (TIMI) 3 flow without in-hospital major adverse cardiovascular events (MACE). The history regarding MACE including death (cardiac & non cardiac), non-fatal myocardial infarction (with or without ST-segment elevation), or need for repeat revascularization (target lesion/vessel revascularization) was collected at discharge and at monthly interval during follow-up by pre determined questionnaires and investigations were performed where necessary. The definition of myocardial infarction and stent thrombosis before and after the index procedure was based on standard published criteria .
Furthermore, we evaluated the occurrence BVS restenosis, defined as a diameter stenosis ≥ 50% within the scaffolded segment or 5 mm proximal or distal to the scaffolded segment by diagnostic coronary angiogram when it was done for symptomatic patients during follow-up. Clinical data were collected by hospital visit or telephone contact at monthly interval post procedure.
2.5
Statistical analysis
Data are presented as mean ± standard deviation (SD) or number (%). Continuous variables were compared with the Student’s t-test or analysis of variance, while discrete variables were compared with the Chi square tests. Any P value less than 0.05 was considered as statistically significant.
3
Results
Among 220 ‘STEMI’ patients admitted during this study period, the clinical and procedural characteristics of the 215 included patients in the present study are presented in Tables 1 and 2 . Only 35 patients (16%) received ABSORB BVS stent and 180 patients received non BVS DES. Only five patients who received BMS were excluded from this study. As compared with those treated with metal drug-eluting stents, patients treated with BVS had a lower prevalence of 3 vessel disease and higher prevalence of 1 vessel disease. Other than that, there were no significant differences seen between the groups in clinical presentation, risk factors or lesion type. Procedural angiographic success was achieved in 94% patients in BVS group and 93% in non-BVS group. There was no significant difference seen in procedural characteristics in both groups except thromboaspiration and post dilation which were more frequently performed in the BVS group. Medication at discharge was the same between the groups. There was no case that developed stent thrombosis in the BVS group, whereas 2 patients in non BVS group developed sub acute stent thrombosis ( Table 3 ) .
| Variable | ABSORB BVS (n = 35) | Non BVS DES (n = 180) | P value |
|---|---|---|---|
| Age (Mean ± S.D) | 59.2 ± 9.0 years | 56.9 ± 12.3 years | NS |
| Sex (M:F) | 30:5 | 142:38 | NS |
| Cardiovascular Risk Factors | |||
| Diabetes | 11 (31%) | 41 (23%) | NS |
| Hypertension | 10 (29%) | 45 (25%) | NS |
| Dyslipidemia | 10 (29%) | 39 (22%) | NS |
| Smoker | 13 (37%) | 56 (31%) | NS |
| COPD | 3 (9%) | 10 (6%) | NS |
| Family H/O CAD | 2 (6%) | 12 (7%) | NS |
| Prior MI | 0 | 4 (2%) | NS |
| Prior PCI/CABG | 1 (3%) | 12 (7%) | NS |
| Type of CAD | |||
| 1 VD | 28 (80%) | 92 (51%) | P = 0.03 |
| 2 VD | 5 (14%) | 45 (25%) | P = 0.05 |
| 3 VD | 2 (6%) | 43 (24%) | P = 0.01 |
| Type of MI | |||
| AWMI | 19 (54%) | 106 (59%) | NS |
| IWMI | 15 (43%) | 65 (36%) | NS |
| LWMI | 01 (3%) | 09 (05%) | NS |
| Ejection Fraction | |||
| > 50% | 25 (74%) | 140 (78%) | NS |
| < 50% | 10 (26%) | 40 (22%) | NS |
| Killip Class | |||
| Class I | 21 (60%) | 128 (71%) | NS |
| Class II | 10 (29%) | 41 (23%) | NS |
| Class III | 04 (11%) | 11 (6%) | NS |
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
