A Case of Symptomatic Paroxysmal Complete Atrioventricular Block

Area of Science:

• Cardiology
• Electrophysiology
• Internal Medicine

Background:

• Paroxysmal complete atrioventricular block (PCAB) is a critical condition where 1:1 atrioventricular conduction abruptly converts to complete heart block.
• PCAB can manifest with diverse symptoms, frequently leading to syncope and posing a risk of sudden cardiac death.
• Existing literature categorizes PCAB into intrinsic, vagal, and extrinsic idiopathic types, yet specific diagnostic markers remain elusive.

Observation:

• PCAB is frequently underdiagnosed due to its intermittent presentation and lack of persistent ECG abnormalities.
• A case study highlights a 65-year-old female with a four-year history of intermittent symptoms ultimately diagnosed with PCAB.
• The unpredictable nature of PCAB challenges routine diagnostic approaches.

Findings:

• The case illustrates the diagnostic challenges associated with PCAB, emphasizing the need for vigilance.
• Sudden changes in atrioventricular conduction are the hallmark of PCAB.
• No single clinical sign reliably differentiates the subtypes of PCAB.

Implications:

• Improved diagnostic strategies are needed to identify PCAB promptly, potentially through continuous monitoring.
• Early diagnosis and management of PCAB can mitigate risks of syncope and sudden cardiac death.
• Further research into the underlying mechanisms and specific diagnostic criteria for PCAB subtypes is warranted.