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Amir R, Vakil RM, Stevenson WG, Tandri H. Oral theophylline for treatment of painful left bundle branch block. HeartRhythm Case Rep 2023; 9:342-346. [PMID: 37361985 PMCID: PMC10285126 DOI: 10.1016/j.hrcr.2023.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023] Open
Affiliation(s)
- Rawan Amir
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Rachit M. Vakil
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - William G. Stevenson
- Division of Cardiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Harikrishna Tandri
- Division of Cardiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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Bera D, Majumdar D, Mukherjee SS, Majumder S, Kathuria S. Unmasking of infra‐Hisian conduction abnormality by intravenous isoproterenol during electrophysiology study for syncope. J Arrhythm 2021; 38:166-170. [PMID: 35222766 PMCID: PMC8851584 DOI: 10.1002/joa3.12663] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/09/2021] [Accepted: 11/23/2021] [Indexed: 11/11/2022] Open
Affiliation(s)
| | | | | | - Suchit Majumder
- Department of Cardiology Apollo Gleneagles Hospital Kolkata India
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3
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Paroxysmal atrioventricular block: are phase 3 and phase 4 block mechanisms or misnomers? Heart Rhythm 2009; 6:1514-21. [PMID: 19968933 DOI: 10.1016/j.hrthm.2009.06.025] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Accepted: 06/15/2009] [Indexed: 02/01/2023]
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4
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Elizari MV. Mauricio Rosenbaum: The Internationally Renowned Electrocardiologist South of the Equator (1921-2003). Ann Noninvasive Electrocardiol 2008; 13:86-91. [DOI: 10.1111/j.1542-474x.2007.00205.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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5
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Abstract
A 32-year-old woman with no structural heart disease was referred for evaluation due to daily occasional palpitations and documented left bundle branch block (LBBB) on surface electrocardiogram (EKG). Continuous 24-hour Holter monitoring revealed a broad range of repetitive intermittent LBBB grades with a rate-dependent pattern that was also associated with circadian variations.
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Affiliation(s)
- Miguel A Arias
- Cardiac Arrhythmia and Electrophysiology Unit, Department of Cardiology, Complejo Hospitalario De Jaén, Jaén, Spain.
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6
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Englund A, Bergfeldt L, Rosenqvist M. Pharmacological stress testing of the His-Purkinje system in patients with bifascicular block. Pacing Clin Electrophysiol 1998; 21:1979-87. [PMID: 9793094 DOI: 10.1111/j.1540-8159.1998.tb00017.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This literature review, based mainly on the English-language literature, focuses on pharmacological stress testing of the His-Purkinje system as part of an invasive electrophysiological study. The main target group for this investigation is patients with bifascicular block and syncope in which intermittent high grade AV block is suspected. Several drugs have been used for this purpose, mainly Class I antiarrhythmic agents such as ajmaline, procainamide, disopyramide, and flecainide. Most studies, unfortunately, suffer from limited patient numbers, lack of adequate control groups, and/or adequate follow-up. The sensitivity of the disopyramide stress test has been shown to be 75%-100% for prediction of impending high grade AV block. The specificity was > 90%. Studies on procainamide have shown a sensitivity of 60% but the specificity has not been assessed. There are no studies allowing a strict comparison of the diagnostic value of pharmacological provocation with different drugs. Based on the similarities of the electrophysiological effects on the His-Purkinje system of the above Class I agents, it is reasonable to assume that all of them might be of diagnostic value in the present clinical context, provided atrial and ventricular stimulation after drug is included in the protocol.
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Affiliation(s)
- A Englund
- Department of Cardiology, Karolinska Hospital, Karolinska Institute, Stockholm, Sweden
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7
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Chiale PA, Sanchez RA, Franco DA, Elizari MV, Rosenbaum MB. Overdrive prolongation of refractoriness and fatigue in the early stages of human bundle branch disease. J Am Coll Cardiol 1994; 23:724-32. [PMID: 8113558 DOI: 10.1016/0735-1097(94)90760-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES The aim of this study was to assess the response of refractoriness in normal and diseased human bundle branches to changes in cycle length, as well as during a long period of continuous overdrive pacing. BACKGROUND The anterograde refractory period of the bundle branches in patients with functional bundle branch block shortens as the rate is increased. The rate-dependent response of refractoriness in diseased bundle branches is quite different. However, this difference has not been precisely delineated, and its physiologic meaning is uncertain. METHODS Refractoriness of the bundle branches was measured by the extrastimulus technique in 16 patients with tachycardia-dependent bundle branch block and 10 patients with functional bundle branch block, both after basic trains of 8 atrial-paced impulses at different cycle lengths and during a 10-min period of continuous overdrive pacing. RESULTS The baseline refractory period in the bundle branches of patients with functional bundle branch block measured 430 +/- 32 ms (mean +/- SD) and shortened to 368 +/- 30 ms at the shortest cycle length. The maximal effect was reached within the 1st min of overdrive pacing. The baseline refractory period of the bundle branches was significantly longer in patients with tachycardia-dependent bundle branch block (611 +/- 184 ms) and demonstrated a cumulative overdrive prolongation in 15 (83%) of 18 studies with typical manifestations of fatigue. In two other studies, this occurred only after ajmaline administration. CONCLUSIONS A rate- and time-dependent prolongation of refractoriness frequently occurs in diseased human bundle branches. When absent, this response may be induced under the effects of sodium channel blockers. This would suggest that an abnormality in the recovery from inactivation of the sodium channel might underlie the early stages of bundle branch disease.
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Affiliation(s)
- P A Chiale
- Division of Cardiology, Ramos Mejia Hospital, Buenos Aires, Argentina
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8
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Chiale PA, Pastori JD, Sánchez RA, Elizari MV, Rosenbaum MB. Contrasting effects of verapamil and procainamide on rate-dependent bundle branch block: pharmacologic evidence for the role of depressed sodium channel responses. J Am Coll Cardiol 1990; 15:633-9. [PMID: 2154512 DOI: 10.1016/0735-1097(90)90638-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The mechanisms responsible for intermittent bundle branch block are still under debate. The role of the time-dependent behavior of the slow calcium channel has recently been emphasized. To test this hypothesis and ascertain the possible involvement of the fast sodium channel, the effects of the slow calcium channel blocker verapamil and the fast sodium channel blocker procainamide were compared in 10 patients with intermittent bundle branch block. All 10 patients showed bundle branch block during spontaneous sinus rhythm. Maneuvers to slow cardiac rate (that is, carotid sinus massage, Valsalva maneuver) were performed to identify normal conduction as well as phase 4 bundle branch block. Thus, the ranges of diastolic intervals (RR) resulting in phase 3 (tachycardia-dependent) bundle branch block, phase 4 (bradycardia-dependent) bundle branch block and normal conduction were measured in two control studies performed before intravenous administration of verapamil (control 1) and procainamide (control 2) and at the peak effect of both drugs. In the control studies, all 10 patients showed phase 3 bundle branch block, whereas phase 4 bundle branch block occurred in only 4 patients. The ranges of phase 3 bundle branch block, phase 4 bundle branch block and normal conduction were very similar in control studies 1 and 2. The phase 3 bundle branch block range was slightly shortened by verapamil (983 +/- 83.5 ms in control 1; 930 +/- 69.4 ms at the peak effect of verapamil), whereas phase 4 bundle branch block remained unchanged. In contrast, conduction was systematically worsened by procainamide.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P A Chiale
- Service of Cardiology, Ramos Mejía Hospital, Buenos Aires, Argentina
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9
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Hernandez R, Mann DE, Reiter MJ. Bradycardia-dependent block and fatigue phenomenon of the His-Purkinje system manifested during upright tilt. Pacing Clin Electrophysiol 1989; 12:1884-9. [PMID: 2481285 DOI: 10.1111/j.1540-8159.1989.tb01880.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Atrioventricular (AV) block occurring in the His-Purkinje system may occur sporadically and can be difficult to document. In this article, we describe two patients with spontaneous episodes of AV block, in whom the use of upright tilt during electrophysiological testing led to a diagnosis of His-Purkinje disease. In both cases, testing in the supine position only uncovered mild or no abnormalities of infra-nodal conduction. In the first case, high grade block distal to the His occurred and the mechanism appeared to be bradycardia-dependent block. In this case, increased sympathetic tone due to upright tilt may have enhanced the slope of phase 4 depolarization in abnormal His-Purkinje cells, leading to block. In the second case, high grade block distal to the His was seen with upright tilt and the mechanism of block appeared to be fatigue phenomenon in the His-Purkinje system. These cases emphasize the elusive nature and varied mechanisms of His-Purkinje block and illustrate the utility of electrophysiological testing in the upright position in patients with suspected conduction system disease.
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Affiliation(s)
- R Hernandez
- Division of Cardiology, University of Colorado Health Sciences Center, Denver 80262
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10
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Lang J, Timour Q, Lancon JP, Aupetit JF, Bertrix L, Faucon G. Effects of isoproterenol and propranolol on pharmacologically induced depression of intraventricular conduction. Fundam Clin Pharmacol 1989; 3:281-94. [PMID: 2767608 DOI: 10.1111/j.1472-8206.1989.tb00457.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The cardiac adrenergic system is known to have practically no influence on conduction velocity in the ventricles under normal conditions. The effects of isoproterenol and propranolol were investigated on depression of intraventricular conduction induced by a class IC antiarrhythmic drug, cibenzoline, in anaesthetized, closed-chest dogs. In addition to electrocardiogram for measurement of QRS duration in sinus rhythm, conduction time was measured in the ventricular contractile tissue between an electrode advanced to the apex and a pacing electrode near the base, at 400- and 200-ms pacing periods. Effective refractory period (ERP) was measured concurrently according to the extrastimulus method. After intraventricular conduction had been slowed down by cibenzoline IV administered (loading dose of 3 mg/kg plus infusion of 0.2 mg/kg/min over 15 min), isoproterenol was infused or propranolol injected by the intravenous route also (0.5 mn/micrograms/kg/min over 5 min and 0.4 mg/kg, respectively). When conduction time has been raised by 75/150% (depending on the pacing rate), isoproterenol appears to attenuate and propranolol to aggravate substantially the impairment of conduction, whereas the reduction undergone by ERP does not differ from usual. Thus, reentrant arrhythmias might be prevented by isoproterenol and triggered by propranolol. Intraventricular conduction, when depressed, therefore, is sensitive to adrenergic drugs, probably because of the enhanced influence of polarization of the fibres in the presence of a sodium conductance impairment.
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Affiliation(s)
- J Lang
- Department of Medical Pharmacology, Claude Bernard University, Lyon, France
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11
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Affiliation(s)
- H Koito
- Department of Medicine, University of Massachusetts Medical School, Worcester
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12
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Markel ML, Miles WM, Zipes DP, Prystowsky EN. Parasympathetic and sympathetic alterations of Mobitz type II heart block. J Am Coll Cardiol 1988; 11:271-5. [PMID: 3339166 DOI: 10.1016/0735-1097(88)90091-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This study examined the effects of changes in parasympathetic and sympathetic tone on the cycle length at which Mobitz type II second degree atrioventricular (AV) block occurred. Four patients who had electrocardiographic evidence of type II AV block and confirmation of block in the His-Purkinje system during electrophysiologic study were evaluated. These patients received intravenous atropine (1.0 to 2.4 mg), propranolol (0.15 mg/kg body weight) or isoproterenol (1 and 2 micrograms/min) alone or in combination. In two of three patients receiving propranolol, the atrial pacing cycle length at which 1:1 His-Purkinje conduction occurred was prolonged relative to control (from 360 to 470 ms and 440 to 590 ms, respectively). In contrast, atropine in the presence of beta-adrenergic blockade shortened the cycle length at which 1:1 His-Purkinje conduction occurred in three of four patients receiving the drug (470 to 390, 630 to 570 and 590 to 560 ms, respectively). Isoproterenol also improved His-Purkinje conduction in the one patient receiving this drug. No agent affected the duration of the HV interval during spontaneous sinus rhythm or right atrial pacing. Thus, drugs that alter autonomic tone influence abnormal His-Purkinje conduction minimally during sinus rhythm but, importantly, may modulate the atrial pacing cycle length at which type II AV block occurs.
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Affiliation(s)
- M L Markel
- Krannert Institute of Cardiology, Indianapolis, Indiana
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Kirkorian G, Touboul P, Atallah G. Electrophysiologic effects of propranolol in intraventricular conduction disturbance. Am J Cardiol 1988; 61:341-5. [PMID: 3341212 DOI: 10.1016/0002-9149(88)90941-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Sixteen patients underwent electrophysiologic studies before and after intravenous infusion of propranolol, 0.1 mg/kg. All of them had intraventricular conduction disturbances. A significant (p less than 0.01) increase occurred after propranolol in the mean spontaneous cycle length (mean change 122 ms) and the AH interval (mean 28 ms). The HV interval did not change significantly. The effective refractory period of the His-Purkinje system increased in 4 of 5 patients (mean net change 44 ms, p greater than 0.10). In 7 patients with phase 3 infranodal block, the longest cycle length for producing block increased after propranolol in 5 and remained unchanged in 2 (mean increase 40 ms, p less than 0.02). Two patients showed phase 4 atrioventricular block. Propranolol increased the critical cycle length by an average of 120 ms. Propranolol-induced bradycardia restored stable atrioventricular conduction in 2 patients with intermittent 2:1 block but facilitated the occurrence of high grade infranodal block in 1 patient. Thus, propranolol can impair His-Purkinje conduction in patients with preexisting infranodal abnormalities.
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Affiliation(s)
- G Kirkorian
- Hôpital Cardiovasculaire et Pneumologique, BP Lyon Montchat, France
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14
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Prystowsky EN, Greer S, Packer DL, Thompson KA, German LD. Beta-blocker therapy for the Wolff-Parkinson-White syndrome. Am J Cardiol 1987; 60:46D-50D. [PMID: 2888300 DOI: 10.1016/0002-9149(87)90708-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Two types of arrhythmias are associated with the Wolff-Parkinson-White syndrome: those in which the accessory pathway is a required part of the reentrant circuit, e.g., orthodromic atrioventricular reciprocating tachycardia, and those that conduct over the accessory pathway but do not require its activation for maintenance of tachycardia, e.g., atrial flutter/fibrillation. Increased sympathetic tone shortens the refractoriness of atrial and ventricular tissue; however, conduction in the atrium and ventricle is not considered the limiting factor for maintenance of atrioventricular reciprocating tachycardia or conduction over the accessory pathway in atrial arrhythmias. Intravenous beta-adrenergic blockers given to patients in the resting state have a minimal to moderate effect in depressing atrioventricular nodal conduction, but have little or no effect on accessory pathway refractoriness or conduction in most patients. In patients presenting with atrioventricular reentry, intravenous administration of beta-adrenergic blocking drugs often is not effective to terminate tachycardia. However, long-term oral therapy with these agents may be beneficial, especially in patients in whom enhanced sympathetic tone is responsible for the initiation or maintenance of tachycardia.
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Waxman MB, Cupps CL. Spontaneous termination of paroxysmal supraventricular tachycardia following disappearance of bundle branch block ipsilateral to a concealed atrioventricular accessory pathway: the role of autonomic tone in tachycardia diagnosis. Pacing Clin Electrophysiol 1986; 9:26-35. [PMID: 2419852 DOI: 10.1111/j.1540-8159.1986.tb05358.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We present a case of an 18-year-old man with a history of palpitations in whom episodes of paroxysmal supraventricular tachycardia were easily initiated by administered atrial premature beats. In all 15 control episodes of tachycardia, functional left bundle branch block (LBBB) seen at the onset, resolved within 10-20 cycles (mean, 13.1 +/- 0.95). The tachycardia ended with the normalized QRS complex in each episode. Eleven episodes ended because of block within the antegrade pathway (ended with a P-wave), and four episodes stopped because of block within the retrograde pathway (ended without a P-wave). During the administration of isoproterenol (1 mg/min IV) all six episodes of tachycardia had LBBB but these did not end when LBBB disappeared spontaneously. When LBBB subsided, the mean tachycardia cycle interval shortened from 328.5 +/- 1.4 to 264.2 +/- 2.1 ms (p less than 0.001). Each episode of tachycardia was then terminated by carotid sinus massage. The disappearance of LBBB in control conditions presented the retrograde and antegrade limbs of the reentrant circuit with an early impulse that stopped the tachycardia. After isoproterenol administration, the tachycardia did not end following disappearance of LBBB, thus enabling the tachycardia cycle interval to shorten by a mean of 64.3 +/- 1.9 ms. This extent of tachycardia acceleration is diagnostic of the participation of a concealed, left free-wall bypass tract.
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Bergfeldt L, Vallin H, Edhag O, Herrlin B, Lagergren H. Paroxysmal complete heart block due to bradycardia-dependent "phase 4" fascicular block in a patient with sinus node dysfunction and bifascicular block. Pacing Clin Electrophysiol 1984; 7:839-43. [PMID: 6207496 DOI: 10.1111/j.1540-8159.1984.tb05625.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A 34-year-old man with ankylosing spondylitis was admitted to the hospital because of syncopal attacks and heart block. Standard ECG, telemetry and an invasive electrophysiologic examination demonstrated right bundle branch block with left anterior fascicular block, sinus node dysfunction with spontaneous slowing of the sinus rate and, as a result, complete infrahisian atrioventricular block in the remaining fascicle at sinus rates below 57 beats per minute. Infrequent supraventricular extrasystoles and abruptly terminated atrial pacing led to the same result. Atrioventricular conduction resumed after three-to-four blocked atrial impulses with successively increasing rate. Pacemaker treatment provided complete symptomatic relief.
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Horio Y, Matsuyama K, Morikami Y, Rokutanda M, Hirata A, Okumura K, Takaoka K, Uchida H, Kugiyama K, Araki S. Blocking effect of verapamil on conduction over a catecholamine-sensitive bypass tract in exercise-induced Wolff-Parkinson-White syndrome. J Am Coll Cardiol 1984; 4:186-91. [PMID: 6736448 DOI: 10.1016/s0735-1097(84)80340-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
By intravenous administration of isoproterenol, 0.5 micrograms/min, a catecholamine-sensitive bypass tract was confirmed in two patients with exercise-induced Wolff-Parkinson-White syndrome. In a 24 year old woman, an intravenous bolus injection of 5 mg of verapamil suddenly blocked conduction over a catecholamine-sensitive bypass tract. In a 62 year old man, the exercise-induced Wolff-Parkinson-White syndrome disappeared after 3 days of oral administration of verapamil (120 mg/day). These observations suggest that a slow inward calcium current plays an important role in conduction over a catecholamine-sensitive bypass tract in exercise-induced Wolff-Parkinson-White syndrome.
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Chiale PA, Przybylski J, Laiño RA, Halpern MS, Nau GJ, Sánchez RA, Lázzari JO, Elizari MV, Rosenbaum MB. Usefulness of the ajmaline test in patients with latent bundle branch block. Am J Cardiol 1982; 49:21-6. [PMID: 7053605 DOI: 10.1016/0002-9149(82)90272-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Twelve patients were studied with intermittent bundle branch block whose conduction disturbance disappeared completely and could no longer be recorded even after provoked changes in heart rate. Premature atrial stimulation and atrial pacing at rapid rates were performed in nine patients; in none of these nine were these procedures able to evoke the complete bundle branch block pattern that all patients exhibited before the spontaneous normalization of conduction. In marked contrast, the administration of ajmaline (1 mg/kg body weight, intravenously in 90 seconds) caused the bundle branch block pattern to reappear in 10 (83.3 percent) of the 12 patients 30 to 120 seconds after the end of the injection, and in 11 patients (91.6 percent) when additional atrial stimulation was performed in 1 of the 2 "failures." This pharmacologic test was much more rapid and simple than electrophysiologic testing and it was noninvasive. Results of this study suggest that some form of subclinical fascicular injury was present (or had persisted) at a time when intraventricular conduction was persistently normal even though no significant physiologic alteration could be demonstrated by the atrial stimulation techniques. The ajmaline test may become a valuable tool for uncovering cases of latent bundle branch block and furthering our knowledge of the early natural history of intraventricular block.
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