270 likes | 530 Views
MUSTELA : A Prospective, Randomized Trial of Thrombectomy vs. no Thrombectomy in Patients with ST-Segment Elevation Myocardial Infarction and Thrombus-Rich Lesions. Anna Sonia Petronio, MD Cardiothoracic and Vascular Department, University of Pisa.
E N D
MUSTELA: A Prospective, Randomized Trial of Thrombectomy vs. no Thrombectomy in Patients with ST-Segment Elevation Myocardial Infarction and Thrombus-Rich Lesions Anna Sonia Petronio, MD Cardiothoracic and Vascular Department, University of Pisa
I, Anna Sonia Petronio, DO NOT have a financial interest/arrangement or affiliation with one or more organizations that could be perceived as a real or apparent conflict of interest in the context of the subject of this presentation.
Study design • First MI with high thrombotic burden • Randomization 1:1 to thrombectomy (Rheolityc/Manual) • Clopidogrel 600 mg oral load before PCI • Abciximab administration during PCI • Stratification for anterior wall MI
C a t h L a b s CardiothoracicDept, University of Pisa M R I Monasterio Foundation-CNR, Pisa CardiologyUnit, Pisa General Hospital Monasterio Foundation-CNR, Massa
Inclusioncriteria • STEMI with symptom onset <12 hours (ST elevation ≥ 2 mm in at least 2 contiguous leads or new LBB block) • High thrombus burden (TIMI thrombus grade ≥3) at diagnostic angiography • No contraindications to abciximab treatment • Written informed consent
Exclusioncriteria • Previous MI in the same ventricular wall • Recent PCI (<2 weeks) • STEMI with cardiogenic shock • Contraindications to abciximab • Contraindications to MRI
Primaryendpoints • Infarct size at 3 months (assessed with delayed-enhancement MRI) • ST-segment elevation resolution >70% at 60 minutes after primary PCI
Secondaryendpoints • Microvascular obstruction (3-month MRI) • Infarct transmurality (3-month MRI) • DysHomogeneous scar (3-month MRI) • Postprocedural TIMI flow grade • Postprocedural TIMI myocardial perfusion grade • MACE-free survival at 1 year
Microvascularobstruction (no-reflow) viable No-reflow Non viable
Homogeneoustransmuralnecrosis w/o microvascular obstruction Voxelcontainingonlyviablemyocites Voxelcontaininingonlyscartissue
dysHomogeneoustransmuralnecrosis w/o microvascular obstruction Voxel containing only viable myocites Islands of viablemyocardium with a scar core or diffuse small scars
Post-processing of dysHomogeneoustransmuralnecrosis Left ventricular mass 160 g Delayedenhancement by manualcontourtracing 42 g (26%) Delayedenhancement by semi-automaticgray-scale analysis 33 g (20%)
Randomized (n=208) Aspiration (n=104) No aspiration (n=104) Rheolytic (n=54) Manual (n=50) No MRI (n=29) Dead (n=2) Refused MRI (n=25) Lost at f-up (n=1) Claustrofobia (n=1) No MRI (n=25) Dead (n=3) Refused MRI (n=21) Lost at f-up (n=1) 3-month MRI (n=41) 3-month MRI (n=38) 3-month MRI (n=75) Primaryendpointanalysis (n=75) Primaryendpointanalysis (n=79) 1-year follow-up n=68 1-year follow-up n=73
Feasibilityofthrombectomy • 98% successful delivery of thrombectomycatheters: • 98% Manual system • 100% Rheolytic system • 1 crossover fromManualtoRheolytic system, whichwassuccessfullydelivered to the culpritlesion • No coronarycomplicationsassociated with thrombectomy (0 dissections, 0 perforations) • No prolongedasystolewithRheolytic system in RCAs (neverplacedtemporary pacemaker beforeaspiration)
1-year freedom from MACEs 93.9±2.4 92.3±2.8 P=0.57
Conclusions • Thrombectomy was not associated with a significant reduction in infarct size at 3-month MRI, even in a high-thrombus burden STEMI population • However, thrombectomy was associated with a significantly higher rate of complete STE resolution, and of post-procedural myocardial perfusion grade 3, and with a lower rate of final TIMI 2 flow
Conclusions • Thrombectomy was associated with a different MRI pattern of myocardial scar at 3 months, with less microvascular obstruction and with areas of viable tissue interspersed with necrotic areas • No significant difference was observed regarding 1-year freedom from MACEs • Angiojet was superior to Export in terms of thrombus removal, but not regarding procedural and MRI results
Conclusions • The lack of benefit in terms of infarct size might be related to: • little role of the prevention of thrombo-embolization during primary PCI in reducing final infarct size • excellent myocardial referfusion in the standard PCI group (clopidogrel pre-load + abciximab) • imbalance between groups, favoring standard PCI group (shorter pain-to-balloon time)