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At least 19 recordsLinked to original sources
PubMed1989

Risk of right bundle-branch block and complete heart block during pulmonary artery catheterization.

The need for the prophylactic insertion of a pacemaker before pulmonary artery catheterization in patients with pre-existing left bundle-branch block (LBBB) is controversial. To determine the incidence of new right bundle-branch block (RBBB) and complete heart block during bedside pulmonary artery catheterization, 293 patients undergoing 307 pulmonary artery catheterizations were prospectively studied. Nine patients had pacemaker rhythms and 19 patients had an RBBB on their precatheterization ECGs and therefore were excluded from analysis. In the remaining 279 pulmonary artery catheterizations, eight (3%) were associated with the development of a new RBBB. None of the 14 patients with a pre-existing LBBB developed complete heart block. The incidence of complete heart block during pulmonary artery catheterization of patients with previous LBBB was not higher than the incidence of RBBB in patients without underlying conduction defects. Because of the rare but grave consequences of RBBB in patients with pre-existing LBBB, we recommend the use of standby external pacemakers and equipment for transvenous pacemaker insertion in these patients during pulmonary artery catheterization. We do not recommend prophylactic pacemaker insertion.

Bundle-Branch Block↗
PubMed1987

Beneficial effects of atrioventricular synchrony in dogs with right coronary artery embolization, and complete heart block.

Complete heart block complicating right ventricular infarction frequently is accompanied by shock. Hemodynamic responses to different pacing modes were studied in six anesthetized, closed chest dogs following right coronary artery embolization with mercury and heart block induced by repetitive trans-septal DC shock. Hemodynamics were recorded at control, following right coronary artery embolization, during atrioventricular sequential pacing (DVI) and ventricular pacing (VVI). With respect to the hemodynamics recorded during VVI and DVI pacing; (1) The mean arterial pressure increased by 29.4% during DVI pacing (92.1 +/- 31.3 mm Hg vs 73.4 +/- 28.9 mm Hg p less than 0.005). This increase was primarily due to an augmentation in systolic arterial pressure. (2) The left ventricular end diastolic pressure increased by 35.8% during DVI pacing (16.3 +/- 5.3 mm Hg vs 12.0 +/- 4.3 mm Hg p less than 0.01). (3) Cardiac output improved by 33.8% during DVI pacing (2.34 +/- 0.75 L/min vs 1.76 +/- 0.59 L/min, p less than 0.0005). This was a consistent improvement in cardiac output with a narrow range of 27.1% to 39.0%. (4) There were no significant changes in right atrial, pulmonary, pulmonary capillary wedge pressures or in systemic vascular resistance. In dogs with right coronary artery occlusion and complete heart block DVI pacing is clearly superior to VVI pacing. This is probably because the atrial contribution to ventricular filling, in this model, is critically important to maintain an adequate cardiac output.

Animals↗
PubMed1976

Progressive improvement of His-Purkinje conduction during recovery from catheter-induced heart block.

Complete heart block developed during HBE studies in a patient with left bundle branch block, after inadvertent catheter-induced trauma to the right bundle branch. Normal intraventricular conduction (HV interval) was documented during the initial part of the study, and was demonstrated to be markedly prolonged after the appearance of heart block. Conduction through the right bundle branch improved over a short period of time as manifested by steplike shortenings of the HV interval, until the original conduction velocity was re-established. This case strongly supports the concept that the His-Purkinje system is capable of varying its conduction velocity and further demonstrates that, in patients with bundle branch block, a prolonged HV interval indicates disease of the remaining bundle branch.

Bundle of His↗
PubMed1992

Prognosis of acute myocardial infarction complicated by complete heart block (the Worcester Heart Attack Study).

As part of a community-based study of patients hospitalized with acute myocardial infarction (AMI) in the Worcester, Massachusetts, metropolitan area, changes over time in the incidence rates of complete heart block (CHB) complicating AMI, and the prognostic impact of CHB on the in-hospital and long-term survival of these patients were examined. In all, 4,762 patients with validated AMI hospitalized at 16 hospitals in the Worcester metropolitan area during 1975, 1978, 1981, 1984, 1986 and 1988 constituted the study sample. The incidence rates of CHB complicating AMI remained relatively stable at 5.8% over the 13-year (1975 to 1988) period studied. The incidence rates of CHB were approximately twice as high in patients with inferior/posterior wall AMI (7.7%) as in those with anterior wall AMI (3.9%). Use of a multivariate regression analysis to control for factors affecting the incidence rates of CHB revealed that patients were at highest risk for developing CHB during the latter 2 study years (1986 and 1988). Patients with AMI developing CHB had higher in-hospital case fatality rates than did those without CHB overall, as well as during each of the 6 periods studied. The in-hospital survival associated with CHB did not improve over time. After use of a multivariate regression analysis to control for additional prognostic factors, the independent effect of CHB on in-hospital prognosis remained (adjusted risk of dying = 2.10; 95% confidence intervals = 1.37, 3.21). Patients with inferior wall AMI complicated by CHB were at significantly increased risk of dying during hospitalization compared with those without CHB (adjusted risk of dying = 2.71; 95% confidence intervals = 1.60, 4.59).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Complete heart block complicating retrograde left heart catheterization.

Three cases of complete heart block complicating retrograde left heart catheterization are presented. In two of the three cases, electrophysiologic study documented block below the AV (atrial ventricular) node. In the third recurrent complete heart block was fatal. It appears that complete heart block complicating retrograde left sided cardiac catheterization is not simply a pericatheterization event; rather, it appears that there is high risk of recurrent complete heart block and that electrophysiologic study is mandatory.

Aged↗
PubMed1975

De subitaneis mortibus. X. Familial congential heart block.

Complete heart block was found shortly after birth in a brother and sister (not twins). Both were treated by electronic pacing because of symptoms attributable to inadequate cardiac output and electrical instability of heart. The boy has done well with his artificial pacemaker and is now six years old. His sister died of complications due in part to the large size of her pacemaker and small size of her body. At necropsy special studies of her heart included the centers for normal impulse formation and concuction. The primary abnormalities were at the junction of atrial septum with atrioventricular (A-V) node, and at the origin of the two bundle branches from the His bundle. The A-V node was isolated by collagen at all its margins except its junction with the His bundle. The proximal His bundle was essentially normal, but from that point on through the initial protions of both the left and right bundle branches there was extensive caseous degeneration which interrupted any possible conduction. These findings are discussed in relation to fetal and postnatal development of the human A-V node, and the His bundle and its branches; and in the context of a recently observed mathematical relationship between sinus rate and two forms of experimentally produced A-V junctional escape rhythms.

Atrioventricular Node↗
PubMed1989

Penicillamine-induced polymyositis with complete heart block.

Complete heart block with severe Adams-Stokes attacks and polymyositis was observed in a 69-year-old man following 6 weeks penicillamine treatment for suspected rheumatoid arthritis. After drug withdrawal the muscle enzymes and the cardiac rhythm gradually normalized, only leaving a right bundle branch block. Although this is the first report to show that severe cardiac damage associated with penicillamine-induced polymyositis is a potentially reversible condition, the severity of the three cases reported so far warrants close observation for cardiac involvement in patients with penicillamine-induced polymyositis.

Aged↗
PubMed1986

Complete heart block.

Complete heart block (CHB) occurs when atrial impulses are not conducted to the ventricles. It occurs in association with many conditions, including acute myocardial infarction. In the setting of acute myocardial infarction (MI), certain characteristic conduction disturbances tend to precede development of CHB. Knowledge of these disturbances provides rational indications for emergency temporary pacing of acute MI patients.

Bundle-Branch Block↗
PubMedDate not supplied

Congenital complete heart block in structurally normal heart--a study of 44 cases.

Data of 44 patients with congenital complete heart block and structurally normal heart have been analysed. Thirty one patients were asymptomatic (group I) and 13 patients had symptoms of low cerebral perfusion like syncope, near syncope or convulsions (group II). A ventricular rate on surface ECG was found to be significantly lower in the symptomatic group (56.7 +/- 13.2 beats per minute, bpm, in group I and 46.5 +/- 6.0 bpm in group II). Similarly wide QRS escape rhythm of greater than 0.10 seconds was more often seen in group II (2/13) as compared to group I (2/31) though the difference did not reach statistical significance. Presence of pauses of more than 3.0 seconds on ambulatory ECG monitoring were infrequent in both the groups (group I 1/7, group II 2/7), however more often seen in group II. Electrophysiological studies carried out in 11 patients were not helpful in differentiating the two groups and all the patients including two with a wide QRS escape rhythm on surface ECG showed suprahisian level of block. The corrected junctional recovery time in two groups did not show any statistical difference. A persistently slow ventricular rate of less than 50 bpm during waking hours, wide QRS escape rhythm and pauses of greater than 3 seconds on ambulatory monitoring are suggestive of high risk to the patient and may justify implantation of permanent pacemaker even in asymptomatic patients.

Adolescent↗
PubMed1992

Complete heart block complicating retrograde left-heart catheterization of patients with cardiac allografts.

The development of complete heart block during left-sided cardiac catheterization is an uncommon event. We describe three cases of complete heart block complicating left-sided cardiac catheterization of patients with cardiac allografts. Review of the cases performed at our institution suggests that complete heart block during left-sided catheterization may be more common in patients with cardiac allografts.

Aged↗
PubMed1976

Prolonged His-Q interval in chronic bifascicular block. Relation to impending complete heart block.

Although prolonged infra-His conduction time in bifascicular block is suspected of denoting trifascicular disease, adquate documentation is lacking concerning the correlation between lengthened His-Q interval (H-Q) and the risk of development of complete heart block (CHB). H-Q in conducted sinus beats in patients with bifascicular block associated with Mobitz II or intermittent CHB represents the approximation of maximal H-Q prolongation prior to onset of trifascicular block. To assess this relationship between prolongation of H-Q and trifascicular block, His bundle electrocardiography (HBE) was performed in 50 patients with chronic bifascicular block exhibiting Mobitz II block or transient CHB. Mobitz II or episodic CHB was shown in all patients: within two days prior to HBE in 45/50 patients; in 39/50 patients during HBE; and following HBE in five patients. In 49/50 patients H-Q was prolonged (greater than 55 msec) and in 47 this interval was substantially lengthened (65 msec or greater). Since marked H-Q prolongation in conducted sinus beats was documented in nearly all patients with bifascicular block associated with intermittent complete trifascicular block, we conclude that a considerably lengthened H-Q interval in bifascicular block is not only a usual prerequisite but strong evidence, for impending complete heart block.

Adult↗