Characteristics and Outcomes of ST-Segment Elevation Myocardial Infarction Due to Left Main Coronary Artery Stenosis

Area of Science:

• Cardiology
• Interventional Cardiology
• Public Health

Background:

• Limited data exists on ST-segment elevation myocardial infarction (STEMI) incidence and outcomes specifically from left main coronary artery (LMCA) lesions.
• LMCA STEMI represents a critical subset of myocardial infarction with potentially severe consequences.

Purpose of the Study:

• To investigate the trends in incidence and outcomes of STEMI caused by LMCA lesions.
• To analyze the utilization of mechanical circulatory support, revascularization strategies, and intravascular imaging in LMCA STEMI patients.

Main Methods:

• Utilized the Nationwide Readmissions Database to identify hospitalizations for LMCA STEMI between January 2016 and December 2022.
• Analyzed in-hospital mortality, incidence of cardiogenic shock (CS), and treatment modalities including mechanical circulatory support, percutaneous coronary intervention (PCI), and intravascular imaging (IVI).

Main Results:

• LMCA STEMI accounted for 0.3% of all STEMI hospitalizations, with a notable increase in incidence and associated cardiogenic shock (CS) over the study period.
• Mechanical circulatory support was used in 78.8% of CS patients, with Impella use rising significantly. Revascularization via PCI was common (62.1%), but intravascular imaging (IVI) use remained low (18.3%) despite an increase.
• All-cause in-hospital mortality was 25.5%, significantly higher in patients with CS (43.4%) compared to those without (11.4%).

Conclusions:

• The incidence of LMCA STEMI and its complication, cardiogenic shock, have increased between 2016 and 2022.
• Despite advances, intravascular imaging use in LMCA PCI is suboptimal. In-hospital mortality for LMCA STEMI remains high, with nearly half of patients experiencing CS and over a quarter dying during admission.