TY - JOUR
T1 - Electrophysiological and clinical observations in patients with alternating bundle branch block
AU - Wu, D.
AU - Denes, P.
AU - Dhingra, R. C.
AU - Amat-Y-Leon, F.
AU - Wyndham, C. R.
AU - Chuquimia, R.
AU - Rosen, K. M.
PY - 1976
Y1 - 1976
N2 - Electrophysiological studies (His bundle recordings and atrial stimulation) were performed in nine patients who manifested periods of both right and left bundle branch block (RBBB and LBBB). In seven of the patients, alternating bundle branch block appeared to reflect intermittent or chronic bundle branch block superimposed on incomplete (but electrocardiographically complete) block of the contralateral bundle branch. In three of these seven, shift from one bundle branch block pattern to the other was associated with reproducible change in H V (mean change 30 msec), and could be induced by alteration of cardiac rate with carotid massage, coupled atrial stimulation, and rapid atrial pacing. In one of the seven, RBBB with a P R of 0.20 seconds preceded chronic LBBB with a P R of 0.24 seconds, implying that RBBB had been incomplete. In three of the seven, although a definite mechanism of alteration could not be demonstrated, transient contralateral bundle branch block occurred superimposed on chronic ipsilateral bundle branch block, implying that the ipsilateral block was incomplete. Two patients manifested periods of narrow QRS, LBBB, RBBB, and paroxysmal A V block. Based upon pathological data (one case), this pattern appeared to reflect a lesion involving the distal His bundle and proximal bundle branches. In the total group of patients, clinical course was primarily determined by the severity of heart disease and not by occurrence of A V block. The conduction defect in the majority of patients was surprisingly benign.
AB - Electrophysiological studies (His bundle recordings and atrial stimulation) were performed in nine patients who manifested periods of both right and left bundle branch block (RBBB and LBBB). In seven of the patients, alternating bundle branch block appeared to reflect intermittent or chronic bundle branch block superimposed on incomplete (but electrocardiographically complete) block of the contralateral bundle branch. In three of these seven, shift from one bundle branch block pattern to the other was associated with reproducible change in H V (mean change 30 msec), and could be induced by alteration of cardiac rate with carotid massage, coupled atrial stimulation, and rapid atrial pacing. In one of the seven, RBBB with a P R of 0.20 seconds preceded chronic LBBB with a P R of 0.24 seconds, implying that RBBB had been incomplete. In three of the seven, although a definite mechanism of alteration could not be demonstrated, transient contralateral bundle branch block occurred superimposed on chronic ipsilateral bundle branch block, implying that the ipsilateral block was incomplete. Two patients manifested periods of narrow QRS, LBBB, RBBB, and paroxysmal A V block. Based upon pathological data (one case), this pattern appeared to reflect a lesion involving the distal His bundle and proximal bundle branches. In the total group of patients, clinical course was primarily determined by the severity of heart disease and not by occurrence of A V block. The conduction defect in the majority of patients was surprisingly benign.
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U2 - 10.1161/01.CIR.53.3.456
DO - 10.1161/01.CIR.53.3.456
M3 - Article
C2 - 1248077
AN - SCOPUS:0017228504
SN - 0891-5849
VL - 53
SP - 456
EP - 464
JO - Unknown Journal
JF - Unknown Journal
IS - 3
ER -