What does Atrial Sensed Ventricular Paced (ASVP) mean?

Atrial Sensed Ventricular Paced (ASVP): A Simple Explanation

Atrial Sensed Ventricular Paced (ASVP) means the pacemaker detects natural electrical activity in the heart's upper chambers (atria) and then sends an electrical impulse to pace the lower chambers (ventricles), maintaining proper coordination between the upper and lower chambers of the heart.

How ASVP Works

• ASVP is part of the VDD pacing mode, where the first "V" indicates that only the ventricle is paced, the first "D" means the device senses both atrial and ventricular activity, and the second "D" indicates a dual response (inhibition by ventricular events and tracking of atrial events) 1, 2

• The pacemaker uses a special lead (wire) that has:

  • Pacing electrodes at the tip positioned in the ventricle to deliver electrical impulses
  • Sensing electrodes on the body of the lead positioned in the atrium to detect natural atrial activity 1, 2

• When the pacemaker detects a natural atrial contraction (P wave), it waits for a programmed interval (AV interval) and then sends an electrical impulse to the ventricle if no natural ventricular activity occurs 2, 3

• This maintains the natural synchrony between atrial and ventricular contractions, which is important for optimal cardiac output 4

Clinical Benefits of ASVP

• Preserves the heart's natural timing sequence between atria and ventricles, known as "AV synchrony" 4

• Allows the heart rate to increase naturally during exercise or stress (chronotropic response) because it follows the natural atrial rate 4

• Improves exercise performance compared to fixed-rate ventricular pacing (VOO or VVI modes) 4

• Studies show that the chronotropic response (ability to increase heart rate) is the major determinant of improved exercise performance in patients with this type of pacing 4

When ASVP Is Used

• Most commonly used in patients with complete AV block or high-degree AV block who have normal sinus node function 2

• Ideal for patients who need ventricular pacing but have normal atrial activity and adequate atrial sensing 1, 2

• Used when atrial contribution to cardiac output is needed for hemodynamic benefit 1, 2

• Beneficial when pacemaker syndrome (symptoms caused by loss of AV synchrony) exists or is anticipated 1, 2

Limitations

• Not suitable for patients with frequent or persistent atrial arrhythmias like atrial fibrillation or flutter 1, 2

• Cannot provide atrial pacing, so it's not appropriate for patients with sinus node dysfunction 1, 2

• If the atrial rate falls below the minimum programmed rate, the pacemaker defaults to functioning like a VVI pacemaker (ventricular pacing only) 2

Practical Example

When you see "Atrial Sensed Ventricular Paced" on an ECG or device report, it means:

• The pacemaker detected a natural P wave (atrial activity)
• After the programmed AV delay, it delivered an electrical impulse to the ventricle
• This maintains the natural sequence of cardiac contraction: atria first, then ventricles 1, 2

This pacing mode helps maintain better cardiac function compared to ventricular-only pacing by preserving the heart's natural timing and allowing for appropriate increases in heart rate during physical activity 4, 5.