NATURE (EnVast As an Adjunct PPCI in Subjects Presenting with STEMI)

Inclusion Criteria:

1. Age ≥ 18 years

2. Chest pain for > 20 min with an electrocardiographic ST-segment elevation ≥ 1 mm intwo or more contiguous electrocardiogram (ECG) leads or an infero-lateral myocardialinfarction (MI) with ST segment depression of ≥ 1 mm in ≥ 2 of leads V1-3 with apositive terminal T wave.

3. TIMI Thrombus Grade ≥ 3 in the infarct related artery. In cases where TIMI ThrombusGrade is equal to 5 (i.e. TIMI 0 flow in the infarcted artery), TIMI Thrombus Gradeof at least 3 has to be re-confirmed with AWI. Patients showing TIMI Thrombus Gradeof less than 3 upon AWI are no longer eligible for randomization.

4. Start of intervention within 8 h of symptom onset

5. Subject is willing and able to provide informed consent prior to the intervention

Exclusion Criteria:

1. Unconscious patients

2. Infarct related artery diameter, at visual assessment, smaller than 2.5 mm

3. Presence of severely calcified plaque(s) proximal to or at the site of the culpritlesion(s)

4. Presence of extreme vessel tortuosity proximal to or at the site of the culpritlesion(s)

5. Women of child-bearing potential (e.g. below 55 years of age, who have not undergonetubal ligation, ovariectomy or hysterectomy and last menstruation within the last 12months)

6. Stent thrombosis as culprit lesion

7. Previous myocardial infarction in the same territory (i.e. same target vessel)

8. Participation in another interventional clinical trial