The Viability-Guided Angioplasty After Acute Myocardial Infarction-Trial (The VIAMI-Trial)

Early and Long-Term Outcome of Elective Stenting of the Infarct-Related Artery in Patients With Viability in the Infarct-Area Early After Acute Myocardial Infarction. The VIAMI-Trial.

The VIAMI-trial investigates the effects of balloon angioplasty with stenting of the infarct-vessel in the early phase after acute myocardial infarction. The study concerns patients who have residual viable tissue in the infarct-area after being treated with thrombolysis. It is postulated that only patients with remaining viable tissue are at high-risk for recurrent infarction or anginal attacks and that stenting of the infarct-vessel will reduce this risk considerably.

Earlier studies have shown that routine angioplasty of the infarct-related coronary artery soon after thrombolysis for acute myocardial infarction did not result in a clinical benefit. This finding emphasizes the importance to select a subgroup of patients with a recent myocardial infarction, who will really benefit from angioplasty of the infarct-related artery.

Several studies have demonstrated that the presence of viability in the infarct-area early after acute myocardial infarction imposes an increased risk of new cardiac events like recurrent infarction, angina pectoris and need for coronary interventions. Therefore, it is postulated that only patients with viability in the infarct-area will benefit from angioplasty early after acute myocardial infarction.

In the VIAMI-trial patients who are admitted to the hospital with an acute myocardial infarction and who did not undergo immediate coronary angioplasty, will undergo viability testing by dobutamine-echocardiography within 3 days of admission. Patients with unequivocal signs of viability in the infarct-area will then be randomized to an invasive or a conservative treatment strategy. In the invasive strategy patients will undergo coronary angiography with the intention to perform balloon angioplasty with stenting of the infarct-related coronary artery, with concomitant use of the intravenous platelet inhibitor abciximab. In the conservative group patients will undergo coronary angiography and angioplasty only when new impending infarction or recurrent ischemia is present. In the invasive group balloon angioplasty will be performed as soon as possible after randomization. Patients without viability will not be randomized,but will participate as a control group.

Inclusion Criteria:

• Admission within 6 hours of pain onset and EKG with ≥ 1 mm ST-segment elevation in two or more standard leads or ≥ 2 mm ST-elevation in two contiguous chest leads, indicative for transmural ischemia, with or without the development of new Q-waves, with myocardial necrosis proven by enzyme rise (total CPK ≥ 2x the upper normal limit).
• Patient history compatible with subacute myocardial infarction ( ≥ 6 hours), with at least signs of myocardial necrosis on the EKG (Q-waves) and a significantly increased serum level of cardiac-specific enzymes.
• Age between 18 and 80 years.
• Viability testing performed prior to coronary angiography.
• No clinical indication for an invasive procedure to be performed before viability testing

Exclusion Criteria:

• No informed consent obtained
• Unreliable follow-up
• Viability testing technically not possible
• Contra-indications for dobutamine echocardiography (heart failure, arrhythmia)
• Contra-indications for coronary angiography, such as severe diabetic nephropathy or know contrast-allergy
• Known hypersensitivity for abciximab
• Serious, life-threatening non-cardiac illness