Left septal fascicular block: Evidence, causes, and diagnostic criteria.

The existence of a tetrafascicular intraventricular conduction system is widely accepted by researchers. In this review, we have updated the criteria for left septal fascicular block (LSFB) and the differential diagnosis of prominent anterior QRS forces. More and more evidence points to the fact that the main cause of LSFB is critical proximal stenosis of the left anterior descending coronary artery before its first septal perforator branch. The most important characteristic of LSFB that has been incorporated in the corresponding diagnostic electrocardiographic criteria is its transient/intermittent nature mostly observed in clinical scenarios of acute (ie, acute coronary syndrome including vasospastic angina) or chronic (ie, exercise-induced ischemia) ischemic coronary artery disease. In addition, the phenomenon proved to be phase 4 bradycardia rate dependent and induced by early atrial extrastimulus. Finally, we believe that intermittent LSFB has the same clinical significance as "Wellens syndrome" and the "de Winter pattern" in the acute coronary syndrome scenario.

Transitory R wave growth in the midst of ST-segment elevation myocardial infarction: A case of left septal fascicular block with atypical electrocardiographic presentation.

We report the case of a patient who presented with angina and ST-segment elevation in the precordial leads owing to a proximal occlusion of the left anterior descending coronary artery. Serial electrocardiography (ECG) showed signs consistent with the left septal fascicular block (LSFB). The latter was observed in conjunction with a pre-existing left anterior fascicular block and presented atypical ECG features, such as intermittent prominent anterior QRS forces (prominent R wave) in V2 only and preserved septal q waves in I and aVL. In the discussion, we present an overview of the electrocardiographic criteria for the diagnosis of the LSFB together with reasons for which LSFB may present with an atypical ECG picture.

Electrocardiographic presentation of acute left main coronary artery occlusion misinterpreted as ventricular tachycardia.

We present a case of acute left main coronary artery (LMCA) occlusion that manifested cardiogenic shock and an ST-segment elevation myocardial infarction (STEMI) electrocardiographic (ECG) pattern comprising "triangular" or "lambda-like" QRS-ST-T complexes. The presenting ECG pattern was misinterpreted as ventricular tachycardia (VT) with resultant delayed emergency percutaneous coronary intervention. The patient died of intractable cardiogenic shock. This case corroborates previous research findings associating the ECG pattern comprising "triangular" or "lambda-like" QRS-ST-T complexes observed in the clinical setting of acute myocardial ischemia with acute LMCA occlusion. Also, we demonstrate how this ECG pattern should be scrutinized for ST-segment elevation in order to avoid misdiagnosing a STEMI for VT.

A patient with simultaneous anterior and inferior ST-segment elevation after percutaneous coronary intervention.

A patient who presented with acute inferior-right ventricular (RV) ST-segment elevation (STE) myocardial infarction (MI) is described. Coronary angiography showed a mid-right coronary artery (RCA) occlusion and high-grade proximal left anterior descending (LAD) artery stenoses. Electrocardiography (ECG) after stent angioplasty to the RCA showed new STE in leads V1-V6. Whereas STE pattern recognition was misleading, ECG analysis using vector concepts enabled exclusion of anterior MI due to proximal LAD artery occlusion and recognition of the RV origin of this ECG picture. The ability of the ECG to "capture" RV dilation that enabled the manifestation of this ECG picture is highlighted.

Meta-Analysis of the Prognostic Impact of Anemia in Patients Undergoing Percutaneous Coronary Intervention.

Anemia is common in patients undergoing percutaneous coronary intervention (PCI), and current guidelines fail to offer recommendations for its management. This review aims to examine the relation between baseline anemia and mortality, major adverse cardiovascular events (MACE), and major bleeding in patients undergoing PCI. We searched MEDLINE and EMBASE for studies that evaluated mortality and adverse outcomes in anemic and nonanemic patients who underwent PCI. Data were collected on study design, participant characteristics, definition of anemia, follow-up, and adverse outcomes. Random effects meta-analysis of risk ratios was performed using inverse variance method. A total of 44 studies were included in the review with 230,795 participants. The prevalence of baseline anemia was 26,514 of 170,914 (16%). There was an elevated risk of mortality and MACE with anemia compared with no anemia-pooled risk ratio (RR) 2.39 (2.02 to 2.83), p <0.001 and RR 1.51 (1.34 to 1.71), p <0.001, respectively. The risk of myocardial infarction and bleeding with anemia compared with no anemia was elevated, pooled RR 1.33 (1.07 to 1.65), p = 0.01 and RR 1.97 (1.03 to 3.77), p <0.001, respectively. The risk of mortality per unit incremental decrease in hemoglobin (g/dl) was RR 1.19 (1.09 to 1.30), p <0.001 and the risk of mortality, MACE, and reinfarction per 1 unit incremental decrease in hematocrit (%) was RR 1.07 (1.05 to 1.10), p = 0.04, RR 1.09 (1.08 to 1.10) and RR 1.06 (1.03 to 1.10), respectively. The prevalence of anemia in contemporary cohorts of patients undergoing PCI is significant and is associated with significant increases in postprocedural mortality, MACE, reinfarction, and bleeding. The optimal strategy for the management of anemia in such patients remains uncertain.

A case of crossing coronary arteries.

We present the case of a patient in whom coronary angiography, performed due to severe calcific aortic stenosis, revealed crossing between the left anterior descending artery and the first diagonal branch. There is only a single report presenting this particular coronary anatomy, whereas this is the eleventh case of crossing coronary arteries ever reported. The clinical implications of this variant coronary anatomy with regard to diagnostic angiography and selection of revascularization procedures are briefly discussed.