Conduction defects ECG Intraventricular conduction delay (defect): constellations of bundle branch blocks and fascicular blocks (hemiblocks) This chapter discusses intraventricular conduction delays (defects), which are…

…Cardiac cell architecture In contrast to skeletal muscle, cardiac cells display a branch like morphology. As illustrated in Figure 2 all cardiac cells are connected…

Cardiology Pulmonary embolism occurs when venous thrombi embolize to the pulmonary artery or its branches. In the majority of cases, the thrombus is formed in…

…of the aortic bulb. The LMCA is short and branches into the two arteries supplying the anterior and left side of the heart, as follows:…

…of the aortic bulb. The LMCA is short and branches into the two arteries supplying the anterior and left side of the heart, as follows:…

…the ischemia/infarction. The location of the thrombus in the artery: a proximally located thrombus will cut off blood flow to more branches, and thus…

…cause transient AV blocks by affecting the AV node, bundle of His or the bundle branches. Tachycardia can cause AV blocks during or after the…

…QRS duration. A QRS duration of 120 ms (0.12 s) or more is required to diagnose a complete left bundle branch block . In addition…

…bundle, which bifurcates into the left and right bundle branches. The left bundle branch further subdivides into two fascicles. From these branches and fascicles, Purkinje…

…and abnormal QRS complex on the ECG. The hallmark of right bundle branch block is QRS duration ≥0,12 seconds, large R' wave in V1…

…near the bundle of His, the impulse may be delivered to both bundle branches and subsequently the entire ventricular myocardium normally. This may yield a…

…jawline, the ears. Anatomically hazardous areas: the branches of the facial nerve at the temple, the accessory nerve in the posterior triangle of the neck…

…defects Serial lesions Vessel size The relationship of the lesion to side branches The extent and distribution of downstream myocardium Collateral circulation Diffuse distal disease…

…length Large thrombotic burdens increase procedural risk because thrombus can fragment, embolize to other coronary branches or vascular beds, propagate through gaps between stent struts…

…likely that the QRS complex will have a left bundle branch block morphology. However, left bundle branch block morphology is more common (regardless of heart…

…and noncoronary cusp (NCC), showing the same branches as in panel A for cross modality comparison. Clinical features Occlusion of the left main coronary artery…

…along with wide QRS complexes (QRS duration ≥0,12 s) there is a high probability that the block is located bilaterally in the bundle branches…

…the ventricles through the bundle of His (which means that both bundle branches will conduct the impulse to each respective ventricle) the QRS complex is…

…depolarized (activated) by impulses spreading through the left and right bundle branch, which branches out into the Purkinje network (refer to Cardiac Electrophysiology: The Action…

…be normal (QRS duration <0.12 s), because both bundle branches receive the impulse and spread it. If the impulse is discharged distal to the…

…ischemia and infarction Conduction defects caused by myocardial ischemia and infarction Bradycardia and conduction defects, such as bundle branch block, fascicular block and AV block…

…outcomes: Mortality in STEMI : Patients presenting with ST elevation myocardial infarction (STEMI) and bundle branch blocks exhibit higher long term and in hospital mortality rates…

…To address these challenges, researchers have developed ECG criteria designed to identify ischemia in the presence of left bundle branch block. The most widely recognized…

Cardiology Introduction Since its initial description in 1992 as a syndrome of right bundle branch block, ST segment elevation, and sudden cardiac death (SCD), Brugada…

…s formula. Note that a QTc interval 480 is always considered pathological. For patients with bundle branch blocks, the corresponding figure is 500 ms. The…

…QT interval (QTc ≥ 480 ms for females) C: Incomplete Right Bundle Branch Block (rSR' pattern in lead V1 and qRS pattern in V6 with QRS…

…latter term has been deprecated. The left bundle branch is subdivided into the following two fascicles: (1) the anterior (anterosuperior) fascicle , which delivers the electrical…

…may cause nonspecific conduction disturbances. Such conduction disturbances may also be superimposed on existing bundle branch blocks and alter their appearance. Some patients develop nonspecific…

…Baseline ECG abnormalities rendering ST T interpretation difficult, including left bundle branch block (LBBB) or pacemaker rhythms. Atrial fibrillation or atrial flutter Patients on medications…

…arising in the atria may have wide QRS complexes if the ventricles cannot be depolarised normally (example: sinus tachycardia together with left bundle branch block)…

…to ask it. Indications Wide complex tachycardia where ventricular tachycardia must be distinguished from supraventricular tachycardia with bundle branch block or aberrancy. Narrow complex tachycardia…

…newly discovered complete heart block without current symptoms, alternating bundle branch block in acute anterior infarction, and before drugs or procedures with a known risk…

…Brugada's algorithm) If the QRS complex in V1–V2 resembles a right bundle branch block (i.e positive QRS) V1 : Monophasic R complex suggests…

…or equal to 1 mm These criteria for the other leads apply in the absence of left ventricular hypertrophy or left bundle branch block [8…

…the internal elastic lamina, and superimposed platelet and fibrin rich thrombus. Lesions preferentially occur at arterial branch points, where disturbed flow, altered shear stress and…

…true lumen Occlusion of a major epicardial artery or bypass graft Side branch occlusion or thrombus Disruption of collateral flow Distal embolization Stent thrombosis Graft…

…or right ventricular involvement Pre existing abnormalities such as prior infarction, left bundle branch block, Wolff–Parkinson–White patterns or ventricular pacing STEMI and non…

…contraindication) . Irregular wide complex tachycardia is most often due to atrial fibrillation with wide QRS complexes due to bundle branch blocks or other conduction defects…

…node, His bundle, Purkinje system) Preexisting AV block, bundle branch block or fascicular block may become worse. Particularly, the degree of AV block may increase…

…be confused with right bundle branch block. Paper speed 50 mm/s. Type 1 Brugada syndrome reminds somewhat of right bundle branch block (RBBB) in…

…must be normal. For example, in the setting of left bundle branch block (LBBB), fractional shortening is not representative of ventricular function, since the activation…

…In addition to stimulation artifacts, ventricular pacing yields wide QRS complexes with LBBB morphology (i.e left bundle branch block appearance). This is explained by…

…at least in some leads). Pacemaker stimulated beats display wide QRS complexes and a left bundle branch block pattern on ECG; this is explained by…

…Second or third degree AV block Depending on the indication Marked anaemia Correct A resting ECG that makes ST interpretation impossible — left bundle branch block…

…developed in conjunction with the European Association of Echocardiography, a branch of the European Society of Cardiology. In Journal of the American Society of Echocardiography…

…originate from the atria but the QRS complexes become wide due to abnormal ventricular depolarization (e.g sinus tachycardia with simultaneous left bundle branch block)…

…prolongation of the Q T interval and sudden death. Am Heart J 1957;54:59 68. Brugada P, Brugada J. Right bundle branch block, persis

…Atherosclerotic lesions commonly arise at sites of disturbed flow, including branch points in the epicardial coronary arteries. Early lesions may undergo positive or compensatory remodelling…

…90 days. The central clinical danger is progressive aortic wall disruption, rupture and compromise of branch vessels. Type A disease may cause cardiac tamponade, severe…

…infrahisian block should be maintained, particularly in older patients and those exhibiting a bundle branch block (BBB) or an intraventricular conduction defect. In severe cases…

…seconds), provided that other causes of right axis deviation have been excluded. Causes of left axis deviation Left bundle branch block. Left ventricular hypertrophy. Inferior…

…seconds), provided that other causes of right axis deviation have been excluded. Causes of left axis deviation Left bundle branch block. Left ventricular hypertrophy. Inferior…

…interventricular) septum The ventricular septum receives Purkinje fibers from the left bundle branch and therefore depolarization proceeds from its left side towards its right side…

…myocardial infarction, long QT, and bundle branch block. Cardiac monitoring is indicated for patients with a high pretest probability of arrhythmia causing syncope. In hospital…

…dyspnea (10%). The major ECG findings in ARVC are T wave inversion in V1–V3 (in the absence of right bundle branch block); virtually all…

…elevations that are not caused by ischemia and a significant proportion have ST T changes caused by other pathological conditions (such as bundle branch blocks)…

…system (which is slow). However, WCTs may be supraventricular, if the tachycardia is accompanied by one of the following conditions: bundle branch block, aberrant v

…from the atria but the QRS complexes become wide due to abnormal ventricular depolarization (e.g. sinus tachycardia with simultaneous left bundle branch block). 2…

…s formula. Note that a QTc interval 480 is always considered pathological. For patients with bundle branch blocks, the corresponding figure is 500 ms. It…

…the R wave and/or notch in the descending limb of the S wave In case of complete/incomplete bundle branch block or pacemaker rhythm…