Supradesnivel del segmento ST en derivación aVR en el síndrome coronario agudo con elevación persistente del segmento ST. revisión de la literatura a propósito de un caso / ST segment elevation in aVR derivation in acute coronary syndrome with persistent elevation of ST segment. literature review following a case

Durante los últimos años, se ha observado la asociación del supradesnivel de ST en la derivación aVR con el compromiso de la arteria descendente anterior (DA), tronco coronario izquierdo (TCI) y coronaria derecha (CD), en el contexto de un infarto de miocardio agudo con segmento ST elevado (IMA-STE). Por medio del electrocardiograma se puede predecir con una probabilidad del 80% el compromiso de TCI frente a DA, cuando la relación aVR sobre V1 es mayor a la unidad. Asimismo, la presencia de un supradesnivel en aVR se asocia a mayor mortalidad a los 30 dias en IMA-STE de cara anterior e inferior. Por lo expuesto previamente, se recalca la importancia del análisis de la elevación del ST en aVR en un IMA-STE de cara anterior puesto que predice compromiso de gran territorio vascular y empeora el pronóstico del paciente.

During last years an association between elevation of the ST segment in the aVR derivation with the affection of the anterior descending coronary artery (ADCA), left coronary artery trunk (LCT) and right coronary artery (RCA) in the context of acute myocardial infarction with elevated ST segment (AMI-ESS) has been observed. The electrocardiogram may predict with 80% accuracy the affection of the LCT versus ADCA when the relation of aVR over V1 in higher than 1. Moreover, an elevation of the ST segment in aVR is associated with higher 30- day mortality in patients with AMI-ESS of the anterior and inferior side. Therefore, we emphasize the importance of analyzing the elevation of the ST segment in aVR in patients with AMI-ESS of the anterior side as it predicts extensive vascular affection and worsens prognosis.

Anomalous Separate Origin of Left Anterior Descending Coronary Artery: Presented as Acute Anterior Myocardial Infarction

Coronary artery anomalies are rare presentations in primary percutaneous coronary interventions of acute myocardial infarction. Herein, we report the case of a 59-year-old man with acute anterior myocardial infarction who had anomalous separate origin of left anterior descending artery (LAD) and left circumflex artery (LCX) from the left coronary aortic sinus. Coronary angiography showed a normal right coronary artery and LCX, but no visualization of the LAD. After several unsuccessful attempts to cannulate the LAD, we found the LAD ostium located by the side of the LCX ostium. There was total occlusion at proxymal LAD. Coronary computed tomography angiography demonstrated the precise, separate origin of LAD and LCX from the left coronary aortic sinus.

Coronary Slow Flow Phenomenon Leads to ST Elevation Myocardial Infarction

The exact etiology of the coronary slow flow phenomenon (CSFP) is not certain. CSFP is not a normal variant as it is an absolutely pathological entity. Furthermore, CSFP not only leads to myocardial ischemia but it can also cause classical acute ST elevation myocardial infarction, which necessitates coronary angiography for a definite diagnosis.

Index of Microcirculatory Resistance as Predictor for Microvascular Functional Recovery in Patients with Anterior Myocardial Infarction

IMR is useful for assessing the microvascular dysfunction after primary percutaneous coronary intervention (PCI). It remains unknown whether index of microcirculatory resistance (IMR) reflects the functional outcome in patients with anterior myocardial infarction (AMI) with or without microvascular obstruction (MO).This study was performed to evaluate the clinical value of the IMR for assessing myocardial injury and predicting microvascular functional recovery in patients with AMI undergoing primary PCI. We enrolled 34 patients with first anterior AMI. After successful primary PCI, the mean distal coronary artery pressure (Pa), coronary wedge pressure (Pcw), mean aortic pressure (Pa), mean transit time (Tmn), and IMR (Pd * hyperemic Tmn) were measured. The presence and extent of MO were measured using cardiac magnetic resonance image (MRI). All patients underwent follow-up echocardiography after 6 months. We divided the patients into two groups according to the existence of MO (present; n = 16, absent; n = 18) on MRI. The extent of MO correlated with IMR (r = 0.754; P < 0.001), Pcw (r = 0.404; P = 0.031), and Pcw/Pd of infarct-related arteries (r = 0.502; P = 0.016). The IMR was significantly correlated with the DeltaRegional wall motion score index (r = -0.61, P < 0.01) and DeltaLeft ventricular ejection fraction (r = -0.52, P < 0.01), implying a higher IMR is associated with worse functional improvement. Therefore, Intracoronary wedge pressures and IMR, as parameters for specific and quantitative assessment of coronary microvascular dysfunction, are reliable on-site predictors of short-term myocardial viability and Left ventricle functional recovery in patients undergoing primary PCI for AMI.

Myocardial Reperfusion and Long-Term Change of Left Ventricular Volume after Acute Anterior Wall Myocardial Infarction

BACKGROUND: In acute myocardial infarction, left ventricular remodeling, which was influenced by infarct size, location, and patency of infarct related artery(IRA), is a important prognostic factor for chronic heart failure and survival. Recently, several reports suggested that patent IRA does not always mean true myocardial reperfusion, and myocardial contrast echocardiography(MCE) may be a useful tool for assessing infarct size and viability of infarcted myocardium. So, we investigated the association between the degree of myocardial reperfusion assessed by MCE and long term change of left ventricular volume in acute anterior wall myocardial infarction patients who had patent IRA. METHODS: The study population was consisted of 17 patients with first acute anterior wall myocardial infarction patients who had patent left anterior descending artery by thrombolytic therapy or rescue PTCA. MCE was done immediately after coronary angiography within two weeks of myocardial infarction onset and analyzed by semiquantitative method to get opacification index. For analysis of left ventricular ejection fraction, wall motion abnormality and left ventricular volume, echocardiogram was taken within 2 weeks of myocardial infarction oneset and 9 months later in each case. Wall motion abnormality was quantified as wall motion index. According to serial changes of left ventricular volume, patients were divided into two groups ; group 1(less than 10% increase of LV volume at follow-up compared to intial echocardiographic exam) and group 2(more than 10% increase of left ventricular volume). We compared the opacification index of infarcted myocardium, wall motion abnormality, and ejection fraction between the two groups. RESULTS: Initial left ventricular volume and ejection fraction were not different between group 1 and group 2, but the opacification index was lower and initial wall motion index higher in group 2 than group 1. Opacification index, wall motion index, ejection fraction and left ventricular volume were closely correlated in the whole cases. By multivariate ananlysis, opacification index was the only significant factor predicting left ventricular volume increment. CONCLUSION: Myocardial reperfusion, which is closely correlated with ejection fraction and wall motion abnormality, acts as a independent predictor of left ventricular dilatation after acute anterior wall myocardial infarction. This result suggests that assessment of microvascular integrity with myocardial contrast echocardiography may be a valuable indicator to predict long-term change of left ventricular volume, although this is suggestive result in a limited number of patients.