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Journal ArticleDOI

Site of Heart Block in Acute Myocardial Infarction

01 Nov 1970-Circulation (Lippincott Williams & Wilkins)-Vol. 42, Iss: 5, pp 925-933
TL;DR: Electrophysiologic observations coupled with previous clinical, anatomic, and pathologic findings suggest that the heart block in DMI is usually due to an ischemic lesion of the A-V node, whileheart block in AMI is due to necrosis involving both bundle branches.
Abstract: Bundle of His electrograms were recorded in eight patients with acute myocardial infarction and heart block. Three patients with diaphragmatic myocardial infarction (DMI) and one with subendocardial infarction were characterized by slowing or block above the bundle of His and A-V junctional escape rhythms during periods of advanced or complete block. An additional patient with DMI had block in the His bundle itself. Intraventricular conduction in the above patients was characterized by normal H-Q intervals (35 to 60 msec) and absence of widened QRS. In contrast, three patients with anterior infarction (AMI) manifested complete block below the bundle of His and idioventricular escape. P-H intervals were normal (80 to 140 msec) and A-V conduction was considered unaffected. Our electrophysiologic observations coupled with previous clinical, anatomic, and pathologic findings suggest that the heart block in DMI is usually due to an ischemic lesion of the A-V node, while heart block in AMI is due to necrosis in...
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Book
05 Jan 2007
TL;DR: Interestingly, clinical cardiac pacing defibrillation and resynchronization therapy that you really wait for now is coming.
Abstract: Interestingly, clinical cardiac pacing defibrillation and resynchronization therapy that you really wait for now is coming. It's significant to wait for the representative and beneficial books to read. Every book that is provided in better way and utterance will be expected by many peoples. Even you are a good reader or not, feeling to read this book will always appear when you find it. But, when you feel hard to find it as yours, what to do? Borrow to your friends and don't know when to give back it to her or him.

279 citations


Additional excerpts

  • ...The site of block in inferior infarction is above the His bundle in about 90% of patients, whereas in anterior infarction, the conduction abnormality is usually localized below the His bundle in the distal conducting system.(187) In the LAC-USCMC series, of the 79 patients with AV block who did not have BBB, 60 (76%) had an inferior infarction, 14 (18%) an anterior infarction, and 5 (6%) a combined infarction (Table 14-6)....

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Journal ArticleDOI
TL;DR: In conclusion, abnormalities of conduction and automaticity in specialized tissue in addition to the sinus node are common in patients with symptomatic sinus nodes disease and should be recognized when present, so that the ideal site for permanent pacing may be chosen.
Abstract: Cardiac conduction was investigated at the time of pacemaker insertion in 15 patients with symptomatic sinus node disease. Techniques included recording of His bundle potentials, atrial pacing at various heart rates, and atropine administration. Atrioventricular (AV) conduction was impaired in eight patients who manifested one or more of the following: P-R prolongation, P-H prolongation, and development of second degree AV block with atrial pacing at heart rates below 130 beats/min. Five patients had intraventricular conduction defects diagnosed electrocardiographically; none of these had H-Q prolongation. One of these five, with left bundle-branch block, subsequently developed complete heart block and had a calcific lesion involving the His bundle. Depression of cardiac automaticity was noted in four patients, with asystolic periods greater than 2 sec after sudden cessation of atrial pacing at rates of 100-160 beats/min. Responses to 1 mg of intravenous atropine were varied, but no patient developed sinus rates greater than 90 beats/min, suggesting the presence of primary sinus node dysfunction. In conclusion, abnormalities of conduction and automaticity in specialized tissue in addition to the sinus node are common in patients with symptomatic sinus node disease. These abnormalities should be recognized when present, so that the ideal site for permanent pacing may be chosen.

251 citations

Book
17 Oct 2011
TL;DR: In this article, the authors propose a method to solve the problem of "uniformity" in the form of a set of points.s 499.s 4.0.
Abstract: s 499

215 citations


Cites background or methods from "Site of Heart Block in Acute Myocar..."

  • ...Similarly, it was recendy shown for rat polymorphonuelear leukocytes that ectophosphatases do not participate in cyanide- and 2-deoxy-glucose-induced catabolism of intracellular AMP [73, 74]....

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  • ...In addition to purinergie nerves, evidenee has been presented in mo re reeent years for the eoexistenee of ATP with the classieal neurotransmitters aeetylcholine (Ach) and norepinephrine (NE) in sympathetie and parasympathetie autonomie nerve terminals and in the motor end-plate of skeletaI muscle, and for its release during nerve aetivation [65-74]....

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  • ...A similar conelusion was recently drawn from experiments on polymorphonuelear leukocytes, using inhibitors of adenosine kinase and adenosine deaminase [74]....

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Journal ArticleDOI
TL;DR: An HLA-B27-associated cardiac syndrome is identified that consists of severe cardiac conduction system abnormalities and lone aortic regurgitation; the link between this syndrome and HLA -B27 is almost as strong as the links between ankylosing spondylitis and Hla-B 27.
Abstract: Purpose: To review the available information about cardiac disease in relation to the immunogenetic marker HLA-B27 and the inflammatory disorders associated with it (seronegative spondyloarthropath...

168 citations

Journal ArticleDOI
TL;DR: The perspective of the comments in this review is at least equally directed to the prehospital phase of acute infarction and to efforts to anticipate, and hopefully prevent, the occurrence of ventricular fibrillation in the hospital.
Abstract: THE TREATMENT of patients with acute myocardial infarction has changed dramatically in the last 8 to 10 years. Since the establishment of coronary care units, the mortality of hospitalized patients has been reduced and the major questions are why and what, if anything, further can be accomplished. Most investigators would agree that the system of coronary care has provided effective means for early recognition, treatment, and in some cases prevention of potentially lethal disturbances of cardiac rhythm. Most would also agree, however, that these accomplishments refer primarily to the recognition of early manifestations of ventricular irritability, their treatment with effective antiarrhythmic agents, and the probable reduction in the incidence of ventricular fibrillation in the hospital.1 2 The bradyarrhythmias are also a common, potentially lethal, and treatable complication of acute myocardial infarction. Perhaps one reason that, until very recently, this problem has received less attention is that bradyarrhythmias represent either a very early (prehospital) or late (postdischarge) complication of infarction and thus fall outside of the experience of the average coronary care unit. Although our own experience is largely with hospitalized patients, the perspective of our comments in this review is at least equally directed to the prehospital phase of acute infarction and to efforts to anticipate, and hopefully prevent,

130 citations

References
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Journal ArticleDOI
TL;DR: The use of this recording technique in man will facilitate diagnostic interpretation of the electrocardiogram and can be used in various investigations of atrioventricular and intraventricular conduction in man.
Abstract: A technique for the routine recording of His bundle (H) activity in man using a bipolar or multipolar catheter is described. The recording catheter is inserted percutaneously, via the Seldinger method, into the right femoral vein and advanced fluoroscopically into the right atrium. Placement of the pre-formed curve at the catheter tip across the tricuspid valve in nine patients resulted in stable recordings of His bundle activity in successive cardiac cycles. Right atrial pacing resulted in progressive lengthening of the P-H interval with increasing frequency but the H to S-wave interval remained constant at all rates. Similar lengthening of the P-H interval was produced during atrial pacing when pressure was applied to the carotid sinus. The use of this recording technique in man will facilitate diagnostic interpretation of the electrocardiogram and can be used in various investigations of atrioventricular and intraventricular conduction in man.

1,112 citations

Journal ArticleDOI
TL;DR: The blood supply of the interventricular septum has been studied in 43 normal human hearts, from patients dying of noncardiac causes, and its clinical importance is discussed.
Abstract: The blood supply of the interventricular septum has been studied in 43 normal human hearts, from patients dying of noncardiac causes. The specimens were prepared by injection of vinylite into the coronary arteries. Description is made of the normal vascular anatomy of this area, and its clinical importance is discussed.

177 citations

Journal ArticleDOI
TL;DR: The presentation was oriented to stress topics of special value to the physician dealing with patients having heart disease.
Abstract: This is a brief perspective review of some personal observations on the normal and abnormal anatomy of the human coronary arteries. Since it is possible to cover in detail but a few aspects of such a broad subject, the presentation was oriented to stress topics of special value to the physician dealing with patients having heart disease.

175 citations

Journal ArticleDOI
TL;DR: The technique of recording His bundle electrograms in man by a tripolar electrode catheter was applied in a study of patients with first, second, and third-degree heart block and the enhancement of A-V conduction due to isoproterenol was qualitatively similar in the three forms of first-degree block.
Abstract: The technique of recording His bundle electrograms in man by a tripolar electrode catheter was applied in a study of patients with first, second, and third-degree heart block. In all patients with first-degree heart block (congenital, acquired, or induced by atrial pacing), the delay in A-V conduction occurred proximal to the His bundle as evidenced by a prolonged P-H interval. The enhancement of A-V conduction (shortening the P-H interval) due to isoproterenol was qualitatively similar in the three forms of first-degree block. In cases of Wenckebach phenomenon the P-H interval progressively increased until a dropped beat occurred. The nonconducted P wave was not followed by a His deflection, indicating block proximal to the His bundle. Cases of 2:1 and 3:1 block occurring proximal to the His bundle were also studied. The usefulness of His-bundle recordings in the diagnosis of cases of complete and incomplete bilateral bundle-branch block is also demonstrated.

167 citations

Journal ArticleDOI
TL;DR: The observations of Mahaim,4 Yater and associates,5 Lev and Unger,6 and Lenegre and Moreau7 strongly suggest that bilateral bundle-branch block may be the usual anatomic substrate of type II A-V block.
Abstract: THE USE OF artificial pacing has greatly intensified interest in chronic A-V block. This interest, in turn, has brought into sharp focus the rare type of A-V block described independently in 1906 by Wenckebach' and by Hay2 and classified by Mobitz in 1924 as type 11.3 This type of block is characterized by failure of a ventricular response, without antecedent progressive lengthening of A-V conduction time. Furthermore, in its more advanced form several consecutive atrial impulses are blocked, giving rise to high degree partial block and to intermittent periods of prolonged ventricular asystole. Although Mobitz had appreciated the distinction between the functional nature of type I and the organic nature of type II block and had stated clearly that type II block was apt to be a forerunner of complete A-V block and Stokes-Adams attacks, it is surprising how the distinction between the genesis and prognosis of these two types of block has become blurred in clinical electrocardiography. Although a definitive anatomic-electrocardiographic study that would relate type II block to a particular anatomic lesion is still missing, the observations of Mahaim,4 Yater and associates,5 Lev and Unger,6 and Lenegre and Moreau7' 8 strongly suggest that bilateral bundle-branch block may be the usual anatomic substrate of type II A-V block. Recent

147 citations