Does the presence of pacemaker spikes or artifacts on an electrocardiogram (EKG) imply that a patient has a pacemaker?

From the Guidelines

The presence of pacemaker spikes or artifacts on an electrocardiogram (EKG) is a strong indicator that a patient has a pacemaker. When an EKG shows pacemaker spikes, these are the visible electrical impulses delivered by the device to stimulate the heart, appearing as small, sharp vertical deflections on the EKG tracing 1. According to the 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay, pacemaker implantation is recommended in certain conditions, such as acquired second-degree Mobitz type II atrioventricular block, high-grade atrioventricular block, or third-degree atrioventricular block not caused by reversible or physiologic causes 1.

The presence of pacemaker spikes or artifacts on an EKG is a direct indication of pacemaker activity, and it is essential to consider the patient's underlying cardiac condition and the reason for pacemaker implantation. The guideline emphasizes the importance of shared decision-making and patient-centered care in treatment decisions, including pacemaker implantation 1.

Key points to consider:

• Pacemaker spikes or artifacts on an EKG indicate pacemaker activity
• Pacemaker implantation is recommended in certain conditions, such as acquired second-degree Mobitz type II atrioventricular block or third-degree atrioventricular block
• Shared decision-making and patient-centered care are essential in treatment decisions, including pacemaker implantation
• The presence of pacemaker spikes or artifacts on an EKG should prompt consideration of the patient's underlying cardiac condition and the reason for pacemaker implantation 1.

In clinical practice, the presence of pacemaker spikes or artifacts on an EKG should be interpreted in the context of the patient's overall clinical picture, including their medical history, symptoms, and other diagnostic findings. The presence of pacemaker spikes or artifacts on an EKG is a strong indicator of pacemaker presence, and it is essential to consider the patient's underlying cardiac condition and the reason for pacemaker implantation 1.

From the Research

Presence of Pacemaker Spikes or Artifacts on EKG

The presence of pacemaker spikes or artifacts on an electrocardiogram (EKG) does not necessarily imply that a patient has a pacemaker. There are several factors to consider when interpreting EKG results:

• Pacemaker spikes can be misleading and may not always indicate the presence of a pacemaker 2
• Automatic capture threshold detection schemes and device testing can produce waveforms on monitors that resemble ventricular tachycardia or pacemaker malfunction 3
• External interference from other devices can cause pacing artifacts on EKG, leading to misinterpretation of pacemaker function 4
• A systematic approach to ECG interpretation is crucial to avoid misinterpretation, including analysis of basic rhythm, paced QRS complex, and signs of pacemaker malfunction 5

Pitfalls in Interpreting Pacemaker ECGs

There are several pitfalls to be aware of when interpreting pacemaker ECGs:

• Pacemaker algorithms can be confused with pathologic failure to output 3
• Undersensing and oversensing can be misinterpreted as pacemaker malfunction 3, 5
• Sophisticated programming features can be misconstrued as pacemaker malfunction 3
• Premature ventricular complexes can cause a pacemaker to inhibit ventricular pacing, leading to a lower than expected heart rate 3

Mechanism of Pacemaker Spikes

The mechanism of pacemaker spikes on EKG can be complex and may involve:

• Double pacing spikes on the T wave, which can occur in single-chamber pacemakers 6
• External interference from other devices, which can cause pacing artifacts on EKG 4
• Pacemaker malfunction, which can be misinterpreted as a normal variant or other cardiac condition 3, 5