Cor Vasa 2014, 56(4):e337-e341 | DOI: 10.1016/j.crvasa.2014.03.003

Patency of the infarct-related artery and time-dependant infarct transmurality on cardiovascular magnetic resonance in patients with ST-segment elevation myocardial infarction treated by primary percutaneous intervention

Łukasz A. Małek^a,c,*, Mariusz Kłopotowski^a, Mateusz Śpiewak^b,c, Jolanta Miśko^c, Witold Rużyłło^d, Adam Witkowski^a

^a Department of Interventional Cardiology and Angiology, Institute of Cardiology, Warsaw, Poland

^b Department of Coronary Artery Disease and Structural Heart Diseases, Institute of Cardiology, Warsaw, Poland

^c Magnetic Resonance Unit, Department of Radiology, Institute of Cardiology, Warsaw, Poland

^d Institute of Cardiology, Warsaw, Poland

Background: Outcome in ST-segment elevation myocardial infarction (STEMI) is affected by patency of the infarct-related artery (IRA) on the initial angiogram. Therefore we decided to assess the relation between patent IRA and time-dependent infarct transmurality.

Materials and methods: The study included 62 patients with first STEMI (age 61 ± 9 years, 76% male) undergoing primary percutaneous coronary intervention (PCI). All patients underwent cardiovascular magnetic resonance (CMR) in the sub-acute phase to assess infarct transmurality. Infarction was considered as transmural if mean infarct transmurality exceeded > 75%. IRA patency was defined as TIMI flow 2 or 3 on the initial angiogram.

Results: Patent IRA at baseline was found in 23 patients (37%) and was related to lower infarct transmurality in comparison to IRA occlusion (46.9 ± 27.3% vs. 82.4 ± 21.3%, p < 0.0001). Patients were divided into three groups according to time-to-PCI (≤ 2 h, > 2-6 h, > 6-12 h). Infarct transmurality increased with increasing time-to-PCI in patients with occluded IRA on the initial angiogram (p = 0.0006), but not in patients with intially patent IRA (p = 0.07). Similarly, the frequency of transmural infarctions increased with longer time-to-PCI in patients with occluded IRA (p = 0.01), but not in patients with initially patent IRA (p = 0.12).

Conclusions: Cardiovascular magnetic resonance demonstrated the relation between initial IRA patency in STEMI and time-dependant infarct transmurality. After 6 to 12 h from the onset of symptoms transmural infarctions were found in all patients with initially occluded IRA and only in about a third of patients with initially patent IRA.

Keywords: Acute myocardial infarction; Delayed enhancement; Infarct-related artery; Late gadolinium enhancement; Patency; Percutaneous coronary intervention; Transmurality

Received: January 21, 2014; Revised: March 8, 2014; Accepted: March 10, 2014; Published: August 1, 2014  Show citation