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Kusumoto et al 2018 Bradycardia Clinical Practice Guidelines

August 20, 2019 Circulation. 2019;140:e382–e482. DOI: 10.1161/CIR.0000000000000628 e446

CLINICAL STATEMENTS AND GUIDELINES 8.	 Atrial arrhythmias are observed in approximately 40% to 45% of patients with congenital heart disease. Large randomized trials such as CTOPP and MOST have shown a decrease in atrial arrhythmias with atrial based pacing in the general population compared with ventricular based pacing modes.S8.2-31,S8.2-32 However, a recent nonrandomized study from a large registry of patients with congenital heart disease found no beneficial effect with atrial based pacing for preventing atrial arrhythmias.S8.2-33

9.	 Lead thrombus and/or vegetations can develop on endocardial pacing leads and have also been identified despite full anticoagulation.S8.2-34 Systemic thromboembolism can therefore occur from these sources by crossing from the venous system and subpulmonic chambers into the systemic circulation. Shunts can exist in various forms such as atrial or ventricular septal defects, or baffle leaks, and can result in distal embolism and brain and peripheral infarction. Nonconventional approaches for pacing therapy should be individualized, and multiple strategies can be considered. In patients in whom epicardial lead placement is not feasible or high risk; open or percutaneous shunt/leak closure may be considered; and rarely, the utilization of higher levels of anticoagulation to prevent lead thrombus.S8.2-17,S8.2-18

8.3 Management of Bradycardia in

Patients With an Acute MI

Recommendations for Management of Bradycardia in the Context of Acute MI Referenced studies that support recommendations are summarized in Online Data Supplement 54.

COR LOE Recommendations

I B-NR 1.  In patients presenting with an acute MI, temporary pacing is indicated for medically refractory symptomatic or hemodynamically significant bradycardia related to SND or atrioventricular block.S8.3-1–S8.3-4

I B-NR 2.  Patients who present with SND or atrioventricular block in the setting of an acute MI should undergo a waiting period before determining the need for permanent pacing.S8.3-1,S8.3-4–S8.3-7

I B-NR 3.  In patients presenting with an acute MI with second-degree Mobitz type II atrioventricular block, high-grade atrioventricular block, alternating bundle-branch block, or thirddegree atrioventricular block (persistent or infranodal), permanent pacing is indicated after a waiting period.S8.3-7,S8.3-8

IIa B-NR 4.  In patients with an acute MI with symptomatic or hemodynamically significant sinus bradycardia or atrioventricular block at the level of the atrioventricular node, the administration of atropine is reasonable.S8.3-9–S8.3-11 III: Harm B-NR 5.  In patients with an acute MI and transient atrioventricular block that resolves, permanent pacing should not be performed.S8.3-1,S8.3-4,S8.3-7,S8.3-12–S8.3-16

III: Harm B-NR 6.  In patients with an acute MI and a new bundle-branch block or isolated fascicular block in the absence of seconddegree or third-degree atrioventricular block, permanent pacing should not be performed.S8.3-17–S8.3-19

Synopsis

Although transient SND may occur in the context of an acute MI, nonreversible injury to the atrioventricular conduction system accounts for most pacing indications. The transient nature of the effects conduction issues in this setting must be considered. For example, SND and atrioventricular block in the setting of an inferior wall MI may be attributable to a transient increase in vagal tone or decreased blood supply to the atrioventricular node or less commonly the sinus node. Temporary pacing does not by itself constitute an indication for permanent pacing. The long-term prognosis for survivors of MI who have had atrioventricular block is related primarily to the extent of myocardial injury and the character of intraventricular conduction disturbances rather than the atrioventricular block itself.S8.3-20,S8.3-21 A major caveat in guiding current therapy is that there have been no RCTs comparing pacing approaches in atrioventricular block complicating an MI. Regardless of whether the infarction is anterior or inferior, the development of an intraventricular conduction delay reflects extensive myocardial damage rather than an electrical problem in isolation.S8.3-22

Recommendation-Specific Supportive Text

1.	 All types of conduction disturbances can occur in the context of an acute MI, and these are influenced by multiple mechanisms (often concomitant) including ischemia, extent and location of MI, reperfusion and autonomic effects affecting electrical conduction or the sinus or atrioventricular node.S8.3-1–S8.3-4 Hemodynamic compromise secondary to significant bradycardia can have deleterious effects on organ perfusion, which can complicate recovery and negatively impact survival (through renal, hepatic or cerebral ischemia). Given the difficulty in assessing reliable myocardial capture with transcutaneous pacing, this method should only be used if other temporary methods are delayed or not available.

Recommendations for Management of Bradycardia in the Context of Acute MI (Continued)

COR LOE Recommendations

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