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Post Conditioning in PCI for Acute ST Elevation Myocardial Infarction

This study has been completed.
Foothills Interventional Cardiology Research Group
Information provided by (Responsible Party):
Todd Anderson, University of Calgary Identifier:
First received: June 6, 2006
Last updated: May 26, 2015
Last verified: May 2015

The purpose of this trial is to compare post-conditioning to standard angioplasty (50/50 chance) in patients who present with an acute heart attack and are taken directly for an angioplasty procedure. Post conditioning is a procedure that involves balloon inflation followed by deflation in a series of cycles that appears to show (based on early data) that it can decrease the amount of damage to the heart muscle as compared to standard angioplasty procedures.

Hypothesis: For Subjects undergoing direct PCI for STEMI, post conditioning with cycles of balloon inflation/deflation within the first minute following the re-establishment of coronary blood blow, will decrease the amount of irreversible myocardial damage assessed by delayed enhancement contrast CMR.

Condition Intervention Phase
Myocardial Infarction
Procedure: Post conditioning
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Post Conditioning in PCI for Acute ST Elevation Myocardial Infarction

Resource links provided by NLM:

Further study details as provided by University of Calgary:

Primary Outcome Measures:
  • Infarct size as measured by: salvage index = total area at risk - infarct size/total area at risk [ Time Frame: 3-5 days post MI ]

Secondary Outcome Measures:
  • Corrected TIMI frame count (cTFC) [ Time Frame: Immediately post PCI ]
  • Myocardial blush score [ Time Frame: Immediately post PCI ]
  • CK release (under the curve) [ Time Frame: 1st 48 hours post MI ]
  • ST segment resolution by 48 hrs compared with admission [ Time Frame: 1st 48 hours post MI ]
  • MRI infarct size [ Time Frame: 3-5 days and 6 months ]
  • MRI maximal transmural extent of irreversible injury [ Time Frame: 3-5 days and 6 months ]
  • CMR regional end-systolic wall stress [ Time Frame: 3-5 days and 6 months ]
  • CMR Myocardial perfusion [ Time Frame: 3-5 days and 6 months ]
  • CMR Myocardial oxygenation [ Time Frame: 3-5 days and 6 months ]
  • Peripheral endothelial function testing (brachial u/s and pulse arterial tonometry) in hospital [ Time Frame: 3-5 days post MI ]
  • CMR quantification of volume of no-reflow [ Time Frame: 3-5 days and 6 months ]

Enrollment: 102
Study Start Date: June 2006
Study Completion Date: October 2011
Primary Completion Date: October 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Post conditioning
Balloon inflations-deflations
Procedure: Post conditioning
4 cycles of balloon inflation /deflation (post-conditioning) within first minute of opening up artery in primary PCI for STEMI vs usual balloon inflation sequence
Placebo Comparator: Standard care
No balloon inflations
Procedure: Post conditioning
4 cycles of balloon inflation /deflation (post-conditioning) within first minute of opening up artery in primary PCI for STEMI vs usual balloon inflation sequence

Detailed Description:

In patients who suffer a myocardial infarction, the blood flow usually ceases due to plaque rupture leading to thrombus formation and vessel occlusion. The resultant entity is known as ST Elevation segment myocardial infarction (STEMI) and is a significant health issue in industrialized countries. There are over 50,000 STEMI's every year in Canada and up to 10% of these patients die in hospital and another 10% die within the first year after their heart attack. The more common problem however is not death, but irreparable damage to the left ventricle leading to LV dysfunction and subsequent heart failure and arrythmias. Re-establishing blood flow promptly by administering plasminogen activators (lytics) or mechanically by performing angioplasty is possible and has lowered the mortality rate dramatically.

Although reperfusion is necessary, it gives rise to an entity known as ischemia-reperfusion where acutely re-establishing blood flow and oxygen levels of the heart has detrimental effects. Clinically this is manifested as no-reflow that causes subsequent damage to the left ventricle and decreases the beneficial affect of early reperfusion by PCI. The ischemia-reperfusion effect sets off a molecular cascade of events involving unfavorable interaction between neutrophils, platelets and endothelium, that is fairly well identified. Efforts to pharmacologically block this effect have not proven to be particularly effective.

Post conditioning follows from a concept of pre-conditioning in animals that showed a decrease in myocardial infarct size. Pre-conditioning is not useful as it requires to be performed prior to the development of ischemia/injury. Post conditioning in preliminary studies with animals and one small study in humans have shown promising results for decrease in infarct size. Post conditioning is a procedure of gradual conditioning in which the artery is opened and closed in cycles with inflation/deflation of the culprit artery followed immediately by standard PCI and placement of stent.


Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • 18 years and over
  • ST elevation of >/= 2mm in 3 consecutive anterior leads or >/= to 2 mm in leads II, III and AVF with total 8 mm ST shift (ST depression of 1 mm in ant or lat leads)

Exclusion Criteria:

  • Cardiogenic shock or severe heart failure
  • Inability to undergo CMR (metallic objects or claustrophobia)
  • Previous MI
  • TIMI 2-3 flow in target artery
  • Collaterals to infarct related artery > Rentrop grade 1
  • Inability to undertake successful PCI at time of angio
  • Significant LM disease or requiring CABG during hospital stay
  • Inability to proceed with post conditioning within 1 minute of establishing blood flow in culprit artery
  Contacts and Locations
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Please refer to this study by its identifier: NCT00334373

Canada, Alberta
Foothills Medical Centre
Calgary, Alberta, Canada, T2N 2T9
Sponsors and Collaborators
University of Calgary
Foothills Interventional Cardiology Research Group
Study Director: Mouhieddin Traboulsi, MD University of Calgary, sub-investigator
Study Chair: Matthias Friedrich, MD Sub-investigator, Stephenson CMR Centre, FMC; 1403-29th St NW, Calgary; T2N 2T9
  More Information

Responsible Party: Todd Anderson, Director Libin Cardiovascular Institute, University of Calgary Identifier: NCT00334373     History of Changes
Other Study ID Numbers: Ethics ID E-20039
Study First Received: June 6, 2006
Last Updated: May 26, 2015

Keywords provided by University of Calgary:
Myocardial infarction
Magnetic Resonance Imaging
Coronary Angioplasty

Additional relevant MeSH terms:
Myocardial Infarction
Pathologic Processes
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Vascular Diseases processed this record on May 23, 2017