Hemiblocks Revisited

Abstract

Abstract-The trifascicular nature of the intraventricular conduction system and the concept of trifascicular block and hemiblock were described by Rosenbaum and his coworkers in 1968. Since then, anatomic, pathological, electrophysiological, and clinical studies have confirmed the original description and scarce advances have been developed on the subject. In the present study, we attempt to review and redefine reliable criteria for the electrocardiographic and vectorcardiographic diagnosis of left anterior and posterior hemiblock. One of the most important problems related to hemiblocks is that they may simulate or conceal the electrocardiographic signs of myocardial infarction or myocardial ischemia and may mask or simulate ventricular hypertrophy. Illustrative examples of these associations are shown to help the interpretation of electrocardiograms. The incidence and prevalence of the hemiblocks is presented based on studies performed in hospital patients and general populations. One of the most common causes of hemiblocks is coronary artery disease, and there is a particularly frequent association between anteroseptal myocardial infarction and left anterior hemiblock. The second most important cause is arterial hypertension, followed by cardiomyopathies and Lev and Lenègre diseases. The hemiblocks may also occur in aortic heart disease and congenital cardiopathies. Left anterior hemiblock is more common in men and increases in frequency with advancing age. Evidence is presented regarding the relationship of spontaneous closure of ventricular septal defects, which may explain the finding of this and other conduction defects in young populations. Isolated left anterior hemiblock is a relatively frequent finding in subjects devoid of evidence of structural heart disease. Conversely, isolated left posterior hemiblock is a very rare finding; its prognostic significance is unknown and is commonly associated with right bundle-branch block. The most remarkable feature of this association is that the prognosis is much more serious with a great propensity to develop complete atrioventricular block and Adams-Stoke seizures. Key Words: epidemiology Ⅲ heart septal defects Ⅲ myocardial infarction Ⅲ heart block Ⅲ bundle-branch block T hirty-eight years have elapsed since Rosenbaum et al published their seminal work that put together diverse previous observations and brought about a rational and complete analytic approach to the trifascicular concept of intraventricular conduction.These conclusive studies and an exhaustive review of the preceding knowledge of the subject were first published in the Spanish monograph, 1 and later a shorter updated version was presented to acquaint the English reader with the electrocardiographic manifestations and clinical correlation of the abnormal spread of ventricular excitation. 2 A series of articles published by the same authors between 1969 and 1973 also contributed to the expansion of the recognition of this research work. As stated by Herman N. Uhley, 3 this work triggered and infl...

Prevalence of electrocardiographic abnormalities in primary care patients according to sex and age group. A retrospective observational study

“…20 However, this abnormality has little or no correlation with poor prognosis and is poorly associated with higher numbers of comorbidities. 20 The prevalence rates for LAH in the combined population aged 40-79.9 years were 5.5%…”

Letter From Yamada et al Regarding Article, “Differentiation of Papillary Muscle From Fascicular and Mitral Annular Ventricular Arrhythmias in Patients With and Without Structural Heart Disease”

“…Anatomically, the LV posterior fascicle begins from the main trunk of the left bundle branch and extends down the LV septal wall, whereas the LV anterior fascicle extends on the LV anterior wall toward the anterolateral papillary muscle. 2 It is known that the LV posterior fascicle is likely to be thicker than the LV anterior fascicle. 2 However, in the article of Dr Al' Aref et al, 1 the fascicle that was located at the higher LV septum as shown in Figures 1, 3, and 5 was called the LV anterior fascicle.…”

“…2 It is known that the LV posterior fascicle is likely to be thicker than the LV anterior fascicle. 2 However, in the article of Dr Al' Aref et al, 1 the fascicle that was located at the higher LV septum as shown in Figures 1, 3, and 5 was called the LV anterior fascicle. Anatomically, this fascicle should be termed the LV septal fascicle.…”

Особенности Предпатологических И Патологических Диагностических Критериев Состояния Миокарда Бывших И Действующих Спортсменов

“…Однако, ресурсы человеческого организма не безграничны, даже если речь идет о профессиональных атлетах [3]. На всех этапах спортивной карьеры, а так же после ее окончания следует особенно тщательно контролировать состояние жизненно важных органов и систем, которые на протяжении спортивной карьеры подвергаются запредельным нагрузкам [4,5].…”

“…Иногда отмечаются противоречивые данные в интерпретации особенностей физиологических и патологических изменений сердечной мышцы у лиц, занимающихся спортом [1,2]. Не выявленная или не верно интерпретированная на начальном этапе кардиологическая патология, в будущем может обернуться необратимыми изменениями, которые в свою очередь, негативно отражаются на спортивных результатах, а после окончания профессиональной карьеры существенно снижают уровень здоровья и качества жизни экс-спортсменов [4].…”