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Perioperative risk of complete heart block in patients with bifascicular block and prolonged PR interval.

Because there is a paucity of information on the perioperative risk of developing complete heart block among patients with bifascicular block (either right bundle branch block and left anterior hemiblock or left bundle branch block) and a long PR interval on the surface electrocardiogram, we undertook an analysis of 76 such patients. Twenty-three patients had right bundle branch block and left axis deviation with a long PR interval and 53 had left bundle branch block with along PR interval. Thirty patients had 37 general anaesthetics, 23 had 32 spinal anaesthetics, and 50 had 64 local anaesthetics or endoscopic procedures. No patient developed complete heart block. Four patients developed sinus bradycardia during general anaesthetics, responsive to atropine or isoproterenol. Similarly, none of the 23 such patients in the literature reviewed had developed complete heart block. Because placement to temporary pacemakers is not without risk, we conclude that prophylactic pacing is not necessary in asymptomatic patients with bifascicular block even in the presence of a long PR interval. Since we did not study patients with recent syncope or myocardial infarction, caution should be exercised in applying these results to such patients.

Aged↗

Heart block after coronary artery bypass--effect of chronic administration of calcium-entry blockers and beta-blockers.

We evaluated risk of heart block after cardiopulmonary by-pass (CPB) in patients with normal conduction undergoing coronary artery bypass grafting who chronically received calcium-entry blockers, beta-blockers, or combined therapy. Before CPB, calcium-entry blockers alone produced an increase in P-R intervals but no change in heart rate; calcium-entry blocker effects were undetectable after CPB, beta-Blockers alone or with calcium-entry blockers produced lower heart rates and longer P-R intervals throughout the entire perioperative period when compared to no therapy (control) or calcium-entry blockers alone. Complete heart block did not occur; one control patient had transient second degree block after CPB. First degree block appeared transiently in 5% of the patients after anesthetic induction and in 15% on emergence from CPB, but was unrelated to drug therapy. We conclude that chronic calcium-entry blocker therapy has minimal effects on conduction perioperatively; beta-blocker effects persist for up to 10 hr after CPB; and the risk of heart block with either drug or combination is low and should not be a factor in their continued administration preoperatively.

Adrenergic beta-Antagonists↗

Hydrops fetalis with complete heart block secondary to congenital lupus: report of one case.

Neonatal lupus erythematosus is an uncommon syndrome characterized by a congenital heart block and/or cutaneous lesion. We report a male newborn with neonatal lupus erythematosus presenting with complete heart block, cutaneous lesions, and hydrops. Transplacental passage of anti-SSA/Ro and anti-SSB/La antibodies were positive. Under the regimens of steroid for maternal systemic lupus erythematosus, perinatal anticongestive agents, and postnatal ventricular pacing with inotropic therapy, the infant died at the age of two days. The prognosis of hydrops fetalis secondary to neonatal lupus with complete heart block is usually fatal.

Heart Block↗

Role of HLA in congenital heart block: susceptibility alleles in children.

Congenital heart block (CHB) is a syndrome of uncertain pathogenesis leading to cardiac conduction disturbances in the foetus and newborns. It has been proposed that maternal antibodies transmit immunological injury in the developing foetal heart, thus causing irreversible damage of the atrioventricular node, leading to third-degree atrioventricular block. However, some genetic or environmental factors may also be involved. We have searched for genetic markers that play a role in immune response and that would be pathognomonic for the disease, either in mothers by regulating their immune response or in children by affecting antigen presentation and target for the maternal immune response. We have compared HLA class I and II alleles of the children with their mother and with healthy individuals and searched for HLA markers that would be emphasized in children. We have shown that particular DQ alleles in the child predispose to CHB, perhaps serving as antigen-presenting molecules on site. In addition, the HLA-Cw3 allele is involved, although its function remains to be clarified. In our results, children with CHB were often identical to their mothers in alleles of DRB, DQA and DQB loci, thus affecting foetomaternal recognition and suggesting that cell-mediated mechanisms could be involved in the pathogenesis.

Adult↗

Risk of advanced heart block during extradural anaesthesia in patients with right bundle branch block and left anterior hemiblock.

Electrocardiographic recording by Holter monitoring demonstrated the absence of any modification, however minimal, of the intranodal conduction during surgical procedures under extradural anaesthesia in 20 patients with right bundle branch block (RBBB) and left anterior hemiblock (LAHB) but without symptoms. These data suggest that extradural anaesthesia can be used safely in patients with asymptomatic chronic RBBB and LAHB without prophylactic insertion of pacemakers. However, patients having experienced either syncope or transient Mobitz II second degree AV block are likely to have a trifascicular block and increased risk of advanced heart block during extradural anaesthesia.

Aged↗

Complete heart block complicating acute myocardial infarction.

Complete heart block (CHB) developed in 10.3% of patients with acute myocardial infarction (MI). It was more frequent among patients with inferior myocardial infarction compared to anterior myocardial infarction, but the mortality was significantly high among patients with anterior MI who developed CHB. A new classification into primary (P) and secondary (S) CHB is suggested by the sequence of events. The incidence and mortality of SCHB was significantly high when compared to the incidence and mortality of PCHB. Wide QRS complexes, a heart rate of less than 60/min, and syncopal attacks were the grave prognostic signs. Progression from a lesser degree of AV block and regression of CHB to a lesser degree of AV Block were both observed in 25.8% cases. Circulatory failure in the form of shock, hypotension, congestive heart failure, and left ventricular failure, alone or in combination was a factor in 17 of the 22 patients who died. Four of 5 patients who underwent transvenous pacing also died.

Acute Disease↗

Double blind crossover comparison of the effects of dual chamber pacing (DDD) and ventricular rate adaptive (VVIR) pacing on neuroendocrine variables, exercise performance, and symptoms in complete heart block.

OBJECTIVE: To compare the effects of dual chamber pacing (DDD) and ventricular rate adaptive pacing (activity sensing) (VVIR) in patients with complete heart block. DESIGN: Double blind crossover comparison with one month in each pacing mode. PATIENTS: 10 consecutive patients aged 23-74 presenting with complete anterograde atrioventricular block at rest and on exercise and with an intact atrial rate response received Synergyst I (Medtronic) pacemakers. MAIN OUTCOME MEASURES: Symptom scores, maximal exercise performance on a treadmill, and the plasma concentrations of atrial natriuretic peptide, adrenaline, and noradrenaline. RESULTS: No significant differences were identified between pacing modes in symptom scores for dyspnoea, fatigue, and mood disturbance; exercise time; and maximal oxygen consumption. One patient with intact ventriculoatrial conduction developed pacemaker syndrome during VVIR pacing. Resting plasma concentrations of atrial natriuretic peptide were raised in complete heart block and were restored to normal by DDD pacing but not by VVIR pacing. Resting plasma catecholamine concentrations were normal in complete heart block and in both pacing modes. During exercise the increase in the concentrations of all three hormones was similar in both pacing modes. CONCLUSIONS: In patients with complete anterograde and retrograde atrioventricular block, symptoms and maximal exercise performance were no better during DDD than during VVIR pacing.

Adult↗

Complete heart block complicating retrograde left ventricular catheterization: case report and review.

Complete heart block (CHB) following retrograde left ventricular catheterization is uncommon. We report a case of transient CHB in a patient with severe aortic stenosis and bifascicular block on the baseline surface electrocardiogram during retrograde left ventricular catheterization. The block resolved spontaneously without sequelae. A review of the literature using MedLine was performed and recommendations for temporary and permanent pacing are outlined.

Aged↗

Acquired congenital heart block. Pattern of maternal antibody response to biochemically defined antigens of the SSA/Ro-SSB/La system in neonatal lupus.

The molecular basis of autoantibody reactivity with components of the SSA/Ro-SSB/La particle exhibited by sera of mothers of infants with severe and permanent manifestations of neonatal lupus (NLE) was investigated using immunoblotting and immunoprecipitation. The characteristics of NLE that were studied included congenital complete heart block (CCHB), second degree heart block, and hepatic fibrosis. Antibodies specific for one or more components of the SSA/Ro-SSB/La particle were found in sera from all 20 mothers of permanently affected infants. However, no antibody specific for a single peptide of this particle was common to all sera. Using tissue extracts from a human cell substrate, 80% of these sera had antibodies to one or more components of the SSA/Ro particle demonstrable by immunoblotting. The predominant antibody response in the NLE group was to the newly recognized 52-kD SSA/Ro peptide component. In contrast, antibodies to the 60-kD SSA/Ro component although present, were the least represented and not significantly increased in frequency among mothers of these infants, compared with a group of 31 mothers with autoimmune diseases such as systemic lupus erythromatosus (SLE) but who had healthy offspring. Antibodies directed to the 48-kD SSB/La antigen were demonstrated in 90% of the NLE mothers often accompanying antibodies against the 52-kD SSA/Ro component. The combination of antibodies to 48- and 52-kD structures was significantly increased in the NLE group, with an odds ratio of 35. The type of cell or tissue substrate was shown to influence detectability of antibodies. The 52-kD SSA/Ro peptide and the 48-kD SSB/La peptide were abundant in cardiac tissues from fetuses aged 18-24 wk, further supporting the possible relevance of these peptides to heart block.

Autoantibodies↗

Ventricular tachycardia secondary to prolongation of the QT interval in a fetus with autoimmune mediated congenital complete heart block.

We report a case where fetal echocardiography identified both complete heart block and ventricular tachycardia. The mother tested positive for anti-Ro antibodies. Prenatal detection of this unusual combination of arrhythmias prompted early postnatal evaluation, which revealed prolongation of the QT interval. Autoimmune mediated congenitally complete heart block associated with such prolongation of the QT interval has a poor prognosis. The child was successfully treated with beta blockers and implantation of a pacemaker.

Adult↗

Congenital complete heart block in the newborn associated with maternal systemic lupus erythematosus and other connective tissue disorders.

Four babies with complete heart block associated with maternal systemic lupus erythematosus (SLE) are described, together with a 5th baby whose mother had serological abnormalities only. One baby had a rapidly fatal outcome, one has required digoxin for heart failure, and the remaining 3 are asymptomatic but remain in complete heart block. Additional manifestations were present in 2 of them. The spectrum of neonatal abnormalities that may occur in association with maternal SLE and related connective tissue disorders is discussed, together with the possible causes and the prognosis. We conclude that congenital heart block is more common than had previously been appreciated.

Adult↗

Risk of developing complete heart block during bedside pulmonary artery catheterization in patients with left bundle-branch block.

We examined the incidence of complete heart block (CHB) as a complication of pulmonary artery catheterization with balloon-tipped, flow-directed catheters in patients with left bundle-branch block (LBBB). The study group included 47 consecutive critically ill patients with LBBB in the medical intensive care and coronary care units, who underwent a total of 82 pulmonary artery catheterizations. Twenty-six patients had an acute myocardial infarction, 34 patients had severe congestive heart failure (Killip class III or class IV), and 15 patients died during their hospitalization. Thirty patients had an old LBBB (more than one month in age), nine patients had a new LBBB, and the age of the LBBB was indeterminate in eight patients. There were five episodes of CHB in the group of patients with old LBBB. However, none of these episodes were related to the pulmonary artery catheterization, since CHB occurred either prior to catheterization (one case) or from one to 16 days after the pulmonary artery catheter had been removed (four cases). There were no episodes of CHB related to the pulmonary artery catheterization procedure in the patients with either old LBBB or indeterminate-aged LBBB. There were two episodes of CHB in patients with new LBBB. In both patients, the CHB occurred one day after the pulmonary artery catheter had been inserted. In both patients, CHB developed after episodes of ventricular tachycardia that eventually resulted in their deaths. Although it is unlikely, we could not rule out the possibility that the CHB was related to the presence of the pulmonary artery catheter. We conclude that the incidence of CHB complicating pulmonary artery catheterization with balloon-tipped, flow-directed catheters in critically ill patients with old or indeterminate-aged LBBB is extremely low. Therefore, we do not recommend the routine placement of a temporary transvenous pacemaker in all patients with LBBB prior to pulmonary artery catheterization.

Aged↗

Pacemaker system failure and other events in children with surgically induced heart block.

Of 1,193 consecutive pediatric (less than 18 years) patients undergoing intracardiac repair from 1975 to 1984, 38 (3.2%) developed surgically induced complete heart block and were treated by permanent pacemaker implantation. Anomalies included complete atrioventricular septal defect = 9 (24%), simple ventricular septal defect = 9 (24%), atrioventricular discordant connection = 8 (212), tetralogy of Fallot = 7 (182), and other complex anomalies = 5 (13%). There were no hospital deaths. follow-up was 100% complete. There were six late deaths = 16%. Actuarial survival was 79 + 9% at 10 years. None of the late deaths were related to disturbance of cardiac rhythm or pacemaker system failure. Twelve patients (32%), required 27 reoperations for various types of pacemaker system failure. Indications for reoperation included: lead failure (44%). Pulse generator failure (44%), and wound sepsis (12%). Actuarial freedom from any pacemaker related reoperation was 50 + 16% at 48 months and 25 + 15% at 96 months. Only first reoperation was found to be an incremental risk factor for subsequent reoperation (p = 0.03). Surgical heart block has been neutralized as a risk factor for hospital death after repair of congenital cardiac defects. The risk of the development of surgical heart block now approaches zero, as indicated by a decreased incidence (1 of 401 = 0.25%) in our institution from 1985 to 1987, as compared to the era 1975 to 1984 (p = 0.001).

Actuarial Analysis↗

Refractory cardiogenic shock and complete heart block after verapamil SR and metoprolol treatment. A case report.

A seventy-eight-year-old woman presented with complete heart block and refractory hypotension two days after a therapeutic dose of sustained-release verapamil with concomitant use of metoprolol. The patient continued to remain hypotensive with complete heart block, even with multiple uses of intravenous atropine as well as high doses of pressor agents such as dopamine and dobutamine. However, shortly after the use of intravenous calcium chloride, the refractory hypotension and complete heart block resolved.

Aged↗

Congenital, complete heart block in the infant of a woman with collagen vascular disease. A case report.

Persistent fetal bradycardia may have multiple etiologies. The following represents a case of persistent fetal bradycardia due to congenital heart block in the infant of a woman with suspected collagen vascular disease. A review of the literature and a discussion of the association of maternal collagen vascular disease and congenital heart block is presented. The prognosis of infants with congenital heart block is reviewed and the possible association with growth retardation discussed.

Adult↗

Anti-SSA/Ro52 autoantibodies blocking the cardiac 5-HT4 serotoninergic receptor could explain neonatal lupus congenital heart block.

The 52-kDa SSA/Ro (Ro52) ribonucleoprotein is an antigenic target strongly associated with the autoimmune response in mothers whose children develop neonatal lupus and congenital heart block. When sera from patients with systemic lupus erythematosus were used as autoimmune controls in an enzyme immunoassay to screen for antibodies against the human serotoninergic 5-HT4-receptor, a high correlation was found between the presence of anti-Ro52 protein antibodies in such sera and antibodies reacting with a synthetic peptide, corresponding to the second extracellular loop of the human 5-HT4 receptor (amino acid residues 165-185). Homology scanning between the 5-HT4 peptide and the sequence of the Ro52 protein indicated two potential common epitopes located between residues 365 and 396 of the Ro52 protein. Cross-reactivity was found between the peptide derived from the 5-HT4 receptor, and a peptide corresponding to residues 365-382 of the Ro52 protein. Autoantibodies, affinity-purified on the 5-HT4 receptor peptide, specifically recognized both the Ro52 protein and the 5-HT4 receptor protein in immunoblots. The affinity-purified antibodies antagonized the serotonin-induced L-type Ca channel activation on human atrial cells. This effect could explain the electrophysiological abnormalities in neonatal lupus.

Adult↗

[Complete heart block and pacemaker therapy in children (author's transl)].

The etiology of congenital and acquired complete heart block is discussed. The prognosis is much better in mostly congenital suprabifurcational blocks, than in the infrabifurcational blocks, which are acquired in most instances. Suprabifurcational blocks are characterized by normal QRS complexes, higher heart rates, and adequate frequency adaptation to exercise. Widened and deformed QRS complexes and fixed heart rates as low as 40--50 beats per minute are typical in infrabifurcational blocks. Whereas children with congenital heart blocks only eventually need pacemakers, the immediate implantation of a pacemaker is mandatory in children with acquired heart blocks after a decrease of the heart rate below 30--40 beats per minute and/or after an Adams-Stokes attack. With demand pacemakers being available, fixed rate systems are obsolete for children. Lithium batteries should be preferred for their smallness and their larger life span. A considerable body of surgical and technical problems due to infection, wire damage, and other complications still awaits solution.

Adolescent↗