Current clinical management of acute myocardial infarction complicated by cardiogenic shock

ABSTRACT

Introduction

Cardiogenic shock (CS) remains the leading cause of death among patients admitted with acute myocardial infarction (AMI). Early restoration of blood flow of the infarct-related artery is of paramount importance, either with percutaneous coronary intervention (PCI) or with coronary artery bypass grafting (CABG). In addition, early risk stratification is a critical task and required to guide complex decisions on management and therapy of CS after AMI. The use of short-term mechanical circulatory support (MCS) is increasing, although evidence for their effectiveness is limited.

Areas covered

We review the evidence for early revascularization of the culprit-lesion and risk stratification in patients with AMI complicated by cardiogenic shock. The current data for the use of MCS will be discussed and put into clinical perspective.

Expert opinion

The SHOCK trial has introduced an early invasive strategy with subsequent revascularization as standard of care in patients with AMI complicated by CS. In clinical practice PCI is the by far the most often used revascularization therapy in CS. Most important is restoration of normal flow (so called TIMI 3 patency) of the infarct artery to reduce mortality. Therefore, all efforts including intense antithrombotic therapy should be made to achieve TIMI 3 patency. Around three quarters of patients with CS have multivessel coronary artery disease. According to the results of the CULPRIT-SHOCK trial PCI of the culprit lesion only is recommended as the preferred revascularization strategy in these patients, while additional lesions can be revascularized during a staged procedure. Immediate multivessel PCI could be performed in some specific angiographic scenarios, such as subtotal non-culprit lesions with reduced Thrombolysis In Myocardial Infarction (TIMI)-flow, or multiple possible culprit lesions. However, this should be considered on an individual basis. CABG should be performed only in case of failed PCI and coronary anatomies not suitable for PCI. However, small case series report good outcomes in selected patients with CS undergoing CABG. Therefore, a randomized trial comparing PCI and CABG in patients with CS and multivessel disease seems warranted. Hopefully such a trial will take place to determine the optimal revascularization therapy in CS. One problem might be to find a sufficient number of cardiac surgeons who are willing to operate such high-risk surgical patients.

KEYWORDS:

• Cardiogenic shock
• acute myocardial infarction
• risk stratification
• revascularization therapies
• mechanical circulatory support

Article highlights

• Cardiogenic shock (CS) remains the leading cause of death among patients admitted with acute myocardial infarction (AMI).

• Left ventricular (LV) failure accounts for the majority CS in AMI patients. Early restoration of perfusion to infarct-related artery is crucial in preventing CS and altering outcomes once it has developed.

• Early risk stratification is a critical task, multiple models to predict clinical outcomes in CS have been proposed, but none is established in the current clinical practice.

• Primary PCI is the preferred reperfusion strategy, but emergency CABG may be indicated in selected patients unsuitable for or with failed PCI.

• The majority of patients who present with CS have multi-vessel disease. Based on the CULPRIT-SHOCK trial, the current European revascularization guidelines do not recommend the routine immediate non-culprit lesion PCI in CS complicating AMI.

• The use of mechanical support devices is increasing despite limited evidence from prospective trials.

Declaration of interest

The authors declare that there is no conflict of interest and they have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.