EUROpean Intracoronary Cooling Evaluation in Patients With ST-elevation Myocardial Infarction.

Summary

In acute myocardial infarction, early restoration of epicardial and myocardial blood flow is of paramount importance to limit infarction size and create optimum conditions for favourable long-term outcome. Currently, restoration of epicardial blood flow is preferably and effectively obtained by primary percutaneous coronary intervention (PPCI). After opening the occluded artery, however, the reperfusion process itself causes damage to the myocardium, the so called "reperfusion injury". The phenomenon of reperfusion injury is incompletely understood and currently there is no established therapy for preventing it. Contributory factors are intramyocardial edema with compression of the microvasculature, oxidative stress, calcium overload, mitochondrial transition pore opening, micro embolization, neutrophil plugging and hyper contracture. This results in myocardial stunning, reperfusion arrhythmias and ongoing myocardial necrosis. There is general agreement that a large part of the cell death caused by myocardial reperfusion injury occurs during the first few minutes of reperfusion, and that early treatment is required to prevent it.

Myocardial hypothermia may attenuate the pathological mechanisms mentioned above. However, limited data are available on the beneficial effects of hypothermia to protect the myocardium from reperfusion damage. In animals, several studies demonstrated a protective effect of hypothermia on the infarction area. This effect was only noted when hypothermia was established before reperfusion. Hypothermia is therefore thought to attenuate several damaging acute reperfusion processes such as oxidative stress, release of cytokines and development of interstitial or cellular edema. Furthermore, it has been shown that induced hypothermia resulted in increased ATP-preservation in the ischemic myocardium compared to normothermia. The intracoronary use of hypothermia by infused cold saline in pigs was demonstrated to be safe by Otake et al. In their study, saline of 4°C was used without complications (such as vasospasm, hemodynamic instability or bradycardia) and it even attenuated ventricular arrhythmia significantly.

Studies in humans, however, have not been able to confirm this effect, which is believed to be mainly due to the fact that the therapeutic temperature could not reached before reperfusion in the majority of patients or not achieved at all. Furthermore, in these studies it was intended to induce total body hypothermia, which in turn may lead to systemic reactions such as shivering and enhanced adrenergic state often requiring sedatives, which may necessitate artificial ventilation.

In fact, up to now any attempt to achieve therapeutic myocardial hypothermia in humans with myocardial infarction, is fundamentally limited because of four reasons:

1. Inability to cool the myocardium timely, i.e. before reperfusion
2. Inability to cool the diseased myocardium selectively
3. Inability to achieve an adequate decrease of temperature quick enough
4. Inability to achieve an adequate decrease of temperature large enough

Consequently, every attempt to achieve effective hypothermia in ST-segment myocardial infarction in humans has been severely hampered and was inadequate. In the last two years, the investigators have developed a methodology overcoming all of the limitations mentioned above. At first, the investigators have tested that methodology in isolated beating pig hearts with coronary artery occlusion and next, the investigators have tested the safety and feasibility of this methodology in humans.

Therefore, the time has come to perform a proof-of-principle study in humans, which is the subject of this protocol.

Conditions

• Acute Myocardial Infarction
• Reperfusion Injury

Interventions

OTHER

Selective intracoronary hypothermia + PPCI

Selective intracoronary hypothermia is a new technique, recently tested for safety and feasibility in the SINTAMI trial. The procedure starts by advancing a guidewire beyond the occlusion in the culprit artery, followed by an OTWB that is inflated at the location of the occlusion, at a low pressure (4 atm), to prevent reperfusion. After that, a pressure/temperature wire will be advanced along the inflated OTWB and is placed in the distal coronary artery. Then the guidewire is removed and the lumen is used for infusion of saline. During the 'occlusion phase', saline at room temperature is infused for 10 minutes with distal coronary temperature 6-8°C below body temperature. After that, the balloon of the OTWB is deflated. Simultaneously, infusion is started with saline of 4°C, the so called 'reperfusion phase'. This is continued for 10 more minutes. After that, the OTWB can be retracted and the procedure can continue not different from routine PPCI.

OTHER

Standard PPCI

PPCI per routine

Sponsors & Collaborators

• Abbott

  collaborator INDUSTRY

• Golden Jubilee National Hospital

  collaborator OTHER_GOV

• Onze Lieve Vrouwziekenhuis Aalst

  collaborator OTHER

• Rigshospitalet, Denmark

  collaborator OTHER

• Örebro University, Sweden

  collaborator OTHER

• Skane University Hospital

  collaborator OTHER

• University of Belgrade

  collaborator OTHER

• Mid and South Essex NHS Foundation Trust

  collaborator OTHER

• Catharina Ziekenhuis Eindhoven

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-01-01

Primary Completion

2022-09-30

Completion

2023-06-30

Countries

• Netherlands

Study Locations