Atrioventricular block pacing

Following septal ablation, patients should be monitored in a coronary care unit for 24 to 48 hours and the temporary pacing wire should be removed at the end of this period in the absence of atrioventricular block. Patients may then be transferred to a telemetry unit for monitoring of arrhythmias. Total hospitalization is usually for three to five days to monitor for occurrence of complete heart block that would require a permanent pacemaker. A sizeable infarction is induced with alcohol ablation and causes creatinine phosphokinase to peak at 1000 to 1500 one day after the ablation. Patients should be maintained on aspirin indefinitely. 

Huang CH, Chen WJ, Wu CC, Chen YC, Lee YT. Complete atrioventricular block after arsenic trioxide treatment in an acute promyelocytic leukemic patient. Pacing Clin Electrophysiol 1999 22(6 Pt l) 965-7. 

Clonidine causes sinus bradycardia and atrioventricular block, as illustrated by two cases, one a 10-year-old boy (6) and the other a 71-year-old woman (7), who developed Wenckebach s phenomenon. Clonidine was also studied in seven patients subjected to electrophysiological studies after 5 weeks of therapy (8). It slowed the sinus rate and increased the atrial pacing rate, producing Wenckebach s phenomenon, indicating depressed function of the sinus and AV nodes. 

Rosen B, Ovsyshcher lA, Zimlichman R. Complete atrioventricular block induced by methyldopa. Pacing Clin Electrophysiol 1988 11(11 Pt l) 1555-8. 

Severe bradypnea and bradycardia requiring external ventricular pacing occurred in a previously asymptomatic 30-year-old woman with a known cardiac conduction defect 85 minutes after a paracervical block with mepivacaine 400 mg (1). First-degree atrioventricular block has been reported (2). 

Initial laboratory data included a blood ethanol of 190 ing/dL, hut electrolytes were normal. An electrocardiogram revealed atrial fibrillation with a high degree of atrioventricular block The ventricular rate did not exceed 50/min. Atropine had no effect on the ventricular rate and a transvenous pacing catheter iros therefore inserted, with ventricular pacing instituted at 60/min. 

Haywood GA, Ward J, Ward DE, Cauun AJ. Atrioventricular Wenckebach point and progression to atrioventricular block in sinoatrial disease. Pacing Clin Electrophysiol. 1990 13 2054-2058. 

Fig. 10.12 (A) Same patient as Fig. 10.11. Pulmonary capillary wedge pressure shows large cannon waves. Scale 0-40mmHg. (B) Same patient after testing with a temporary dual chamber pacemaker with a physiologic AV delay. Note the normal pulmonary capillary wedge pressure. The patient was markedly improved after the implantation of a dual chamber pacemaker with AV delay optimization. (Barold SS. Acquired Atrioventricular Block. In Kusumoto F, Goldschlager N (Eds), Cardiac Pacing for the Clinician, Philadelphia, PA Lippincott, Williams Wilkins, 2001 with permission).

Connelly DT, Steinhaus DM. Mobitz type I atrioventricular block an indication for permanent pacing PACE 1996 19 261-264. 

Toff WD, Camm AJ, Skehan JD. Single-chamber versus dual-chamber pacing for high-grade atrioventricular block. N Eng J Med 2005 353 145-55. 

In a prospective study of 42 patients (33 men median age 49 years) who had been hospitalized with mad honey intoxication, all had nausea, vomiting, dizziness, fainting, and sweating five had syncope [106"]. The mean blood pressure was 73/52 mmHg and the mean heart rate 38/minute 18 had sinus bradycardia, 15 had complete atrioventricular block, and nine had nodal rhythm. None needed temporary pacing and all were discharged without complications. 

Auricchio A, Stellbrink C, Block M, et al. Effect of pacing chamber and atrioventricular delay on acute systolic function of paced patients with congestive heart failure. Circulation 1999 99 2993-3001. 

A 17-year-old boy took propafenone 3 g and had a sudden cardiac arrest with h5fpotension, left ventricular failure, bradycardia, sinoatrial block, and an atrioventricular junctional and ventricular tachycardia. He was treated with temporary cardiac pacing, catecholamines, and sodium bicarbonate, and the toxicity resolved within 4 hours [66 ]. 

A dual chamber pacemaker (with one lead In the atrium and another in the ventricle) provides versatile programming functions and can sense and pace In both the atrium and ventricle. This type of pacemaker mimics the normal cardiac cycle and maintains atrioventricular (AV) synchrony. It may be used for patients with chronic or intermittent AV block and for those who need atrial pacing or have delayed AV conduction or an increased risk of heart block. 

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