Infarction apical-anterior

Figures 5.13-5.17). This electrocardiographic pattern corresponds to the so-called apical-anterior infarction. Compared to the A-l pattern, it exhibits a Q wave (QS or qr morphology) beyond lead V2 and usually beyond V3. 

It is called apical-anterior infarction because it corresponds to infarcted area usually... 

The typical apical-anterior infarction is a consequence of LAD occlusion, clearly distal to the D1 and SI. If there is anteroseptal extension, it is usually due to non-complete LAD occlusion im-... 

Figure 5.15 The ECG pattern of apical-anterior infarction (type A-2) with important anteroseptal extension as may be seen in this example but preserving the basal area of septum (D) and anterior wall (E). The lateral extension only involves the low part (D). The lack of involvement of segment 12 and lesser involvement of segment 7 are the...

Figure 5.16 (A, B) Example of apical-anterior infarction seen in cases of apical-anterior Ml with anteroseptal with inferior involvement equal to or greater than the involvement greater than the inferior involvement (C).

The pattern of the extensive anterior infarction is usually explained by proximal LAD occlusion,above the take-off of the SI and D1 branches. Naturally, the infarction also extends to the apical area and here the four walls are always involved (except when the LAD is very short). But the difference with the apical-anterior infarction lies in that in the latter although an-teroseptal wall maybe involved, the basal portion of LV is spared and the involvement of lateral wall is lesser. The extensive anterior infarction, on the other hand, reaches the mid-lateral wall and the basal areas in some walls, generally the anterior and septal walls, but not lateral wall (Figure 5.18), because as we have already said the basal segments of lateral wall, even the anterior portion, are perfused by the LCX (OM) (see Figure 5.4C). 

Electrocardiographic pattern of apical-anterior infarction (Figure 5.9A(2))... 

A Q wave in VI to V3-V6 may be seen in apical-anterior infarction with or without anteroseptal extension. The presence of a Q wave in II, III and VF supports that inferior infarction being equal to or more important than anterior infarction is a typical apical infarction. 

The smallest apical-anterior infarctions due to very distal LAD occlusion often do not exhibit... 

Sometimes there is an rS morphology in VI-V2 with Q in other precordial leads. This corresponds to apical-anterior infarction with more lateral than septal involvement (R wave in Vl-V2). 

On rare occasions apical-anterior infarctions especially with anteroseptal extension that corresponds to A-2 pattern presents with an ECG of type A-3 (extensive anterior), because an abnormal pattern is recorded not only in precordial but also in leads I and VL (QS and QR patterns). The changes caused by cardiac rotation (levorotation) or the presence of LVH, among other factors, may at least partially explain it. In the levorotated and... 

Some limitations exist in the presence of Q waves in the precordial leads with respect to knowing the real extension of the infarction. This is especially true when distinguishing between the apical-anterior infarction (type A-2) and the extensive anterior infarction (type A-3). 

Infarctions with a Q wave in V1-V4 and sometimes qrs or qR in V5-V6 usually with a negative T wave correspond to apical-anterior infarction (distal occlusion of LAD) with or without anteroseptal extension, and most of the cases that in addition to having a Q wave in the precordial leads exhibit QS or QR patterns in VL (and/or lead I) corresponding to an extensive anterior infarction (proximal occlusion of LAD). 

As regards the infarcted area, apical-anterior infarctions do not affect a large portion of the left-ventricular lateral wall, while in extensive anterior this wall is more affected. 

In a few cases, the electrocardiographic patterns of apical-anterior infarction (Q wave in the precordial leads, but not in leads I and aVL) correspond to extensive anterior infarctions (Figure 5.7). Additionally, in some rare cases, electrocardiographic patterns of extensive anterior infarction (Q wave in the precordial leads and I and aVL) correspond, in fact, to apical-anterior infarctions. 

Figure 5.39 (A) Apical-anterior infarction in subacute phase. Observe QS in V2-V3 with ST-segment elevation and small ST-segment elevation in II (occlusion distal to S1 and D1) (see p. 1.80). (B) Six months later another infarction occurs with appearance of r in V1-V3 and mild... 

Electrocardiographic pattern type A-2 (Figure 5.9-A2) Q wave in Vl-V2to V4-V6 (Figures 5.13-5.17). This corresponds to apical-anterior infarction. At times, the extension of the infarction involves upper areas especially of the anterior and... 

However, the infarctions with the best prognosis are the apical-anterior infarctions due to very distal, not very long, LAD occlusion since these are the smallest (Figure 5.16A). These maybe considered true apical infarctions. 

Occlusion proximal to the SI branch but distal the D1 branch (Figure 4.25 and Table 4.1A(4)) When the occlusion is located above, the SI but not the D1 (Figure 4.25), which rarely occurs (<15% of the STE-ACS), the area at risk could lead to a relatively extensive anterior infarction when the D1 branch is quite small and the D2 branch is large. However, usually more septal and anterior than lateral involvement is seen (Figure 4.25B,C). Currently, with the new treatments employed in the acute phase, most of these cases end up being just an apical infarction... 

The infarction is generally a consequence of non-complete LAD occlusion,which has partly or totally involved the septal branches, but not the diagonal branches, or due to complete distal occlusion of LAD after all the diagonal branches take off. Otherwise, the infarction would be of the A-2 type (apical-anterior). On some rare occasions it maybe secondary to the exclusive occlusion of one septal branch (Figure 4.29). This may occur spontaneously or during the course... 

The typical pattern of apical-anterior MI (QS in V1-V4) with more or less extension up to V6, but not in leads I and VL, is explained by the infarction vector directing posteriorly, but not rightwards, since not much lateral involvement is present (the 6 and 12 segment are spared). Consequently, the QRS loop is oriented generally posteriorly from the beginning and, sometimes, with initial forces directed anteriorly, but... 

In some infarctions with QS pattern from VI to V4, the presence of a Q wave is observed in II, III, and VF, with qr or QS pattern. This occurs in typical apical infarctions, but not in case of important anteroseptal extension (Figure 5.16), since in the former, inferior infarction is frequently as important or more than anterior infarction, with the infarction vector of inferior wall and the corresponding loop in the FP, being directed upwards (Figure 5.16A). In... 

This electrocardiographic pattern (QS in VI to V4-V6), as has already been mentioned, may be seen in apical-anterior MI with and without evident anteroseptal extension. In case of very distal LAD occlusion the sensitivity of this pattern is lower, since apical infarctions secondary to a very distal LAD occlusion allow for the recording of the first vector (rS in V1-V2), and the Q... 

A thorough assessment of II, III and VF provides useful information about anteroseptal involvement in the cases of apical-anterior MI. If infarction Q waves are present in II, III and VF, the infarction of inferior wall probably equally or predominantly involves this wall with respect to the anterior wall (very long LAD). If tall R waves are present in II, III and VF, the inferior involvement is probably small or absent (short LAD). 

Figure 9.2 Apical-anterior Ml. (A) ECG showing Q waves in V1-V3 with rS V4-V5 corresponding to an apical-anterior myocardial infarction. (B) CE-CMR image in a sagittal view myocardial hyperenhancement (arrows) shows a non-transmural necrosis of the anterior wall. (C-E) Transversal images show myocardial hyperenhancement (arrows) at low basal, mid and apical levels of the anterior...

We will just remind (see p. 137) that seven areas of MI detected by CE-CMR have good correspondence with seven ECG patterns (four in anteroseptal zone - septal, apical-anterior, extensive anterior and mid-anterior - and three in the inferolateral zone - inferior, lateral and infero-lateral) (Figure 5.9 Cino et al., 2006). We have also demonstrated that in clinical practice the presence of these seven ECG patterns correlates well with the corresponding infarction areas detected by CE-CMR, and therefore these have real value in clinical practice (Bayes de Luna et al., 2006a-c) (Table 5.3). Therefore, in chronic infarction the correlation between ECG changes (Q waves of necrosis) and involved area (CE-CMR) is clearly good (88% global concordance). However, the in-farcted area of apical infarction (A-2 type), mid-anterior infarction (A-3 type) and lateral infarction (B-l type) presents the lower concordance. 

A healthy 33-year-old man with prior cocaine use had a small myocardial infarction and, 36 hours later, having inhaled cocaine, developed a dissection of the left main coronary artery, extending distally to the left anterior descending and circumflex arteries. There was marked anterolateral and apical hypokinesis. 

The VCG has been used to locate the presence of multiple infarctions. However, this technique is rarely used in daily practice. Furthermore, as we have already stated, it has been demonstrated that practically the same information may be obtained if the ECG-VCG correlation is used to understand ECG morphologies, as is done in this book (Warner et al., 1982). We need to also have in mind that, in some cases of single infarction, Q waves in leads of different areas may be seen, e.g. in an apical infarction due to a distal LAD occlusion, in addition to Q waves in the precordial leads these may also be seen in the inferior wall when the LAD is very long and there is infarction of the inferior wall that may be even greater than the anterior involvement (Figure 5.16). 

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