From the Guidelines
For patients with second-degree type 1 (Wenckebach) atrioventricular (AV) block, permanent pacing is reasonable if they have marked block with symptoms that are clearly attributable to the atrioventricular block, as stated in the 2019 ACC/AHA/HRS guideline 1. The treatment approach for second-degree type 1 (Wenckebach) AV block depends on the presence of symptoms and the underlying cause of the block.
- Asymptomatic patients typically do not require treatment.
- For symptomatic patients, the first step is to address any underlying causes, such as discontinuing medications that slow AV conduction (e.g., beta-blockers, calcium channel blockers, digoxin), correcting electrolyte abnormalities, treating myocardial ischemia, or managing inflammatory conditions.
- According to the 2019 guideline, permanent pacing may be considered for patients with marked first-degree or second-degree Mobitz type I (Wenckebach) AV block with symptoms that are clearly attributable to the AV block, as indicated by a Class IIa recommendation with a Level of Evidence of C-LD 1. Key considerations in the management of second-degree type 1 AV block include:
- The block's location, with those occurring below the AV node potentially requiring more aggressive treatment.
- The presence of underlying cardiac conditions, such as myocardial infarction or cardiomyopathy, which may influence the treatment approach.
- The patient's overall clinical status and the presence of any comorbidities that may impact the risk-benefit ratio of permanent pacing. The 2019 ACC/AHA/HRS guideline provides a comprehensive framework for the evaluation and management of patients with bradycardia and cardiac conduction delay, including those with second-degree type 1 AV block 1.
From the FDA Drug Label
Do not rely on atropine in type II second-degree or third-degree AV block with wide QRS complexes because these bradyarrhythmias are not likely to be responsive to reversal of cholinergic effects by atropine. The treatment for second-degree type 1 (Wenckebach) atrioventricular (AV) block is not explicitly stated in the provided drug label.
- The label only mentions that atropine should not be relied upon in type II second-degree or third-degree AV block.
- No information is provided about the treatment of type 1 (Wenckebach) second-degree AV block. 2
From the Research
Treatment for Second-Degree Type 1 (Wenckebach) Atrioventricular (AV) Block
The treatment for second-degree type 1 (Wenckebach) atrioventricular (AV) block depends on the presence of symptoms and underlying heart disease.
- For asymptomatic patients without organic heart disease, the prognosis is relatively benign, and permanent pacing may not be necessary 3.
- For symptomatic patients or those with underlying heart disease, treatment options include:
- Permanent pacemaker (PPM) implantation, which is the standard of care for patients with complete heart block or second-degree type II AV block, but may not be necessary for second-degree type I AV block unless symptoms are present 4.
- Catheter ablation, which can be used to alleviate symptomatic AV block due to a ventricular nodal pathway interfering with AV conduction 5.
- Pharmacological treatment, although this may not always be successful 6.
- In some cases, temporary pacemaker implantation may be recommended, especially in patients undergoing surgery 7.