Does electrocardiogram help in identifying the culprit artery when angiogram shows both right and circumflex artery disease in inferior myocardial infarction?

OBJECTIVE: In a subgroup of patients with inferior myocardial infarction (MI), both the right coronary artery (RCA) and circumflex coronary artery (Cx) show potentially culprit lesions, and angiography may be insufficient to determine which artery is responsible for the clinical presentation. Although many electrocardiographic (ECG) algorithms have been proposed for identifying the infarct-related artery in patients with inferior MI, it is unclear whether the current algorithms have the discriminative power to identify the real culprit artery in these patients. METHODS: The patients with the diagnosis of acute inferior MI and underwent coronary angiography were enrolled in the study. The prediction of the infarct-related artery was attempted from the admission ECG using published algorithms and criteria. For the angiographic definition of the infarct-related artery, multiple criteria were used. RESULTS: Total 417 inferior MI cases were enrolled during the study period; the final patient population comprised of 318 patients. Forty-five patients (14.2%) had both RCA and Cx lesions on coronary angiography. Although several criteria and algorithms are able to identify the infarct-related artery in the general inferior MI population, they lose their strength in patients with both RCA and Cx lesions. Only the Aslanger-Bozbeyoglu criterion emerges as a more powerful diagnostic test with a sensitivity, specificity, and c-statistic of 80%, 48%, and 0.650, respectively for the whole population (p<0.001) and 81%, 58%, and 0.709, respectively, for patients with both RCA and Cx lesions (p=0.019). CONCLUSION: The Aslanger-Bozbeyoglu criterion is not only helpful in differentiating the infarct territory in combined inferior and anterior ST-segment elevation as previously shown, but also valuable in identifying the infarct-related artery in patients with inferior STEMI with critical lesions in both the RCA and the Cx. (Anatol J Cardiol 2020; 23: 318-23).

Is the inferior ST-segment elevation in anterior myocardial infarction reliable in prediction of wrap-around left anterior descending artery occlusion?

OBJECTIVE: In a subgroup of patients with the anterior wall myocardial infarction (MI), the electrocardiogram (ECG) records a concomitant inferior ST-segment elevation (STE), which is generally explained by a 'wrap-around' left anterior descending (LAD) artery occlusion. However, recent evidence indicates that this may be due to a distal LAD occlusion, which may be irrelevant to the LAD length. We investigated the relationship between inferior ST-T changes in anterior MI and the presence of a wrap-around LAD. METHODS: Consecutive patients diagnosed with anterior MI due to an acute LAD occlusion were enrolled into the study. All ECGs were measured manually by a cardiologist, who was blinded to the angiographic outcomes. The site of the LAD occlusion was determined using multiple angiographic views. A wrap-around LAD was defined as a LAD artery from a post-reperfusion coronary angiogram that perfused at least one-fourth of the inferior wall of the left ventricle in the right anterior oblique projection. RESULTS: A total of 379 anterior MI cases were enrolled, and the final study population consisted of 259 patients. The presence of a wrap-around LAD was more frequent in patients presenting with inferior STE compared with patients without inferior STE (62.1% vs. 30.4%, p=0.001), however, this relationship was weak (φ=0.211). Inferior STE was more frequent in distal occlusions (22.9% vs. 4.3%, p<0.001), which showed a stronger relationship (φ=0.285). The polarity of the T-wave in lead III did not give any clues about the LAD anatomy. CONCLUSION: Contrary to the popular acceptance, our results indicate that a wrap-around LAD cannot be reliably diagnosed by ECG.

[Prasugrel in clinical practice: Frequently asked questions]. / Klinik pratikte prasugrel: Sik sorulan sorular.

This section includes evidence based short answers to frequently asked questions regarding the clinical use of prasugrel.