Acute diagonal-induced ST-elevation myocardial infarction and electrocardiogram-guidance in the era of primary coronary intervention: New insights into an old tool

Abstract

Background: Previous studies, published before the advent of primary reperfusion, described the electrocardiographic features of ST-segment elevation myocardial infarction (STEMI) caused by total diagonal artery occlusion, as demonstrated at pre-discharge coronary angiography. We aimed to assess the electrocardiographic and echocardiographic features in STEMI unequivocally attributed to a diagonal lesion in the era of primary coronary intervention. Methods: The electrocardiograms and echocardiograms of patients sustaining STEMI caused by diagonal artery involvement were compared with those of patients with STEMI attributed to proximal or mid left anterior descending artery (LAD) lesions. ST-segment deviations were measured at four different points in each lead and analyzed against TIMI flow and SNuH score. The electrocardiographic and echocardiographic features of each group were mapped. Results: In contrast to previous studies claiming an ever-present incidence of at least 1-mm ST-segment elevation in leads I and aVL with diagonal STEMI, we report 86% of any ST-elevation in leads I, aVL and V2 (64-71% for ST-elevation >1 mm). Both higher SNuH score and pre-intervention TIMI flow were associated with larger lateral ST-elevations (85.7% and 86.4-95.5%, respectively). Higher prevalence of ST-depression in the inferior leads reflecting reciprocal changes was observed in patients with diagonal-induced STEMI (57-76% vs. 24-51% in LAD obstructions, p <0.05). Conclusion: The most sensitive and predictive sign for acute ischemia was any degree of ST-deviation measured 1 mm beyond the J point. ST-elevations in I, aVL and V 2 , sparing V 3-V 5 , strongly favor isolated diagonal lesion. Proximal LAD lesion lacking ST-segment elevations in leads I and aVL is primarily due to wraparound LAD anatomy.

New ECG Algorithm for the Prediction of Culprit Vessel in Acute Myocardial Infarction Involving Lateral Part of the Ventricle: Ilkay Classification

“…Vessel size is the most commonly used parameter to define the clinical significance of a side branch. 13 Koo et al developed a new scoring system (SNuH score) that incorporated the number and distribution of branches as well as the size, to better reflect the myocardial mass at risk ([(Size (S), vessel diameter ≥2.5 mm; Number (Nu) number of diagonal branches ≤2; Highest (H), no branch below the target branch)]). They stated that SNuH score was higher in branches with ST-segment elevation.…”

“… 9 Fanne et al reported that more severe lateral lead ST-elevations were related to higher SNuH score and pre-intervention TIMI flow. 13 …”

“…However, information about the changes in the precordial leads is less common. 13,14 According to the latest ESC Guidelines for the management of acute STEMI, ST elevation in leads I and aVL meet classic STEMI criteria. 3 However, isolated diagonal occlusion often will not meet STEMI criteria due to presence of the ST elevation noncontiguous leads aVL and V2.…”

The diagonal branches and outcomes in patients with anterior ST- elevation myocardial infarction

“…Loss of D flow might be associated with poor prognosis of patents with STEMI. However, the clinical significance of the two occlusion scenarios is quite different, with the former being most common, of greater severity, and with worse prognosis [11,13,14], while isolated D occlusion is relatively rare and appears mainly inconsequential [15]. Therefore, distinction between the two scenarios is of clinical relevance.…”

The year in review: electrocardiogram analysis and acute coronary syndromes

“…Fanne et al studied the ECG and echocardiographic findings of 123 STEMI patients that underwent coronary angiography in a retrospective series to determine whether the culprit vessel for primary PCI was the first diagonal or the proximal or mid LAD branch. 8 They reported that any degree of STE measured at the J-point + 40 ms localized to leads I, aVL, and V2, sparing leads V3–5, associated with reciprocal inferior ST segment depression was more likely to be associated with a proximal diagonal branch lesion compared with STE in leads V1 and V3–6, in which correlated with a proximal LAD lesion. The most common wall motion abnormalities associated with the first diagonal branch were localized to the apical-lateral, apical-anterior, and apical-inferolateral regions.…”