Heart Block, 3rd Degree - Drug Therapy

2/23/00 (Doyle)

Group: Wednesday Residents

RE: A 25 year old African-American male with multiple episodes of near-syncope.

Question: What is the safety & efficacy of epiniphrine and other drugs in the treatment of 3rd degree (or complete) heart block?

  Dr. Horlander chose #9 as 'excellent' and 

  the remainder shown here as 'good'. - KHW

<9>

Unique Identifier: 79240911

Authors: Lash R. Coker J. Wong BY.

Abstract: The role of glucocorticosteroid therapy for myocardial sarcoidosis is not well defined. This report shows the effect of prednisone therapy on atrioventricular (AV) conduction in a patient with myocardial sarcoidosis and AV block. On three separate occasions AV block was documented prior to prednisone therapy. On the first two occasions the patient had first and second degree AV block which by His bundle electrogram initially was shown to be in the AV node. On the third occasion the patient developed complete heart block. On each occasion treatment with prednisone resulted in improved AV conduction. The results indicate that prednisone therapy can be beneficial in the treatment of AV block due to myocardial sarcoidosis.

<2>

Unique Identifier: 99387348

Authors: Brady WJ. Swart G. DeBehnke DJ. Ma OJ. Aufderheide TP.

Institution: Department of Emergency Medicine, University of Virginia, Charlottesville 22908, USA. wb4z@hcsmail.mcc.virginia.edu

Abstract: OBJECTIVE: To determine the efficacy of atropine therapy in patients with hemodynamically compromising bradycardia or atrioventricular block (AVB) in the prehospital and emergency department settings. METHODS: DESIGN: Retrospective review of prehospital, emergency department, and hospital records. PARTICIPANTS: Prehospital patients with hemodynamically compromising bradycardia or AVB with evidence of spontaneous circulation who received atropine as delivered by emergency medical services personnel (advanced life support level). SETTING: Urban/suburban fire department-based emergency medical service system with on-line medical control serving a population of approximately 1.6 million persons. DEFINITIONS: Hemodynamic instability was defined as the presence of any of the following: ischemic chest pain, dyspnea, syncope, altered mental status, and systolic blood pressure less than 90 mmHg. Bradycardia was defined as sinus bradycardia, junctional bradycardia, or idioventricular bradycardia (grouped as bradycardia) while AVB included first-, second- (types I and II), or third-degree (grouped as AVB). The response that occurred within one minute following each dose of atropine was defined as none, partial, complete, or adverse. MAIN RESULTS: Of 172 patients meeting entry criterion complete data was available for 131 (76.1%) and constitutes the study population. The mean age was 71 years. Fifty-one percent were female. Forty-five patients had AVB and 86 bradycardia. Patients with AVB were more likely to have a presenting systolic blood pressure less than 90 mmHg than those with bradycardia. In the 131 patients, responses to atropine were as follows: 26 (19.8%) = partial, 36 (27.5%) = complete, 65 (49.6%) = none, and 4 (2.3%) = adverse. Patients presenting with bradycardia (compared to AVB) more commonly: (1) received a single dose of atropine; (2) a lower total dose of atropine in the prehospital interval; (3) were more likely to arrive in the ED with a normal sinus rhythm; and (4) were less likely to receive additional atropine or isoproterenol in the ED. Those patients who achieved normal sinus rhythm over the total course of care were likely to have achieved that rhythm during the prehospital interval. There was no difference between groups in the likelihood of leaving the ED with a normal sinus rhythm achieved during the ED interval. Acute myocardial infarction was more common in patients presenting with AVB (55.5%) than with bradycardia (23.2%, P = 0.001). CONCLUSIONS: Approximately one-half of patients who received atropine in the prehospital setting for compromising rhythms had either a partial or complete response to therapy. Adverse responses were uncommon. Those patients who presented with hemodynamically unstable bradycardia to EMS personnel responded more commonly to a single dose and a lower total dose of atropine compared to similar patients with AVB. Those patients who achieve normal sinus rhythm by ED discharge were likely to have achieved it during the prehospital interval.

<3> Link Directly to Fulltext article in Ovid

Unique Identifier: 95390587

Authors: Bertolet BD. McMurtrie EB. Hill JA. Belardinelli L.

Institution: University of Florida Health Sciences Center, USA.

Abstract: OBJECTIVE: To show that second- or third-degree atrioventricular block occurring as an early complication of acute inferior myocardial infarction is mediated by adenosine. SETTING: Cardiac care unit. DESIGN: Uncontrolled, observational, hypothesis-driven study. PATIENTS: Patients who developed clinically significant atrioventricular nodal blockade within 4 hours of admission for acute inferior myocardial infarction. INTERVENTION: Theophylline, 100 mg/min intravenously to a maximum of 250 mg. MEASUREMENTS: Continuous multilead electrocardiographic monitoring before and after administration of theophylline. RESULTS: During a 6-month period, eight men who had had acute inferior myocardial infarction developed clinically significant atrioventricular block. Three had third-degree block, and five had high-grade second-degree block. In all patients, 1:1 atrioventricular nodal conduction was restored and normal sinus rhythm reappeared within 3 minutes of the administration of theophylline. All patients remained free of arrhythmia for at least 24 hours. CONCLUSIONS: Adenosine produced by the ischemic myocardium may induce atrioventricular nodal block. In our patients, atrioventricular nodal block was resistant to conventional therapy such as atropine, but it responded to the adenosine antagonist theophylline.

<5>

Unique Identifier: 92411128

Authors: Stamler JS. Rodgers C. Hirano I. Brezinski D. Sharma GV.

Institution: Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115.

<11>

Unique Identifier: 70030128

Authors: De Saint Pierre G.