DALLAS, April 15, 2021 — Former Vice President Mike Pence is recovering after having a pacemaker successfully implanted to improve a slow heart rate, according to statement from his office released to media outlets today.  A full recovery is expected. The statement says Pence was diagnosed with "asymptomatic left bundle branch block." 

"Left bundle branch block indicates that that one of the electrical pathways regulating the normal rhythm of the heart is not functioning. Because the heart has another conduction pathway called the right bundle, patients with left bundle branch block are generally asymptomatic. They are monitored on a regular basis by their cardiologist. If patient with a left bundle branch block develops a slow heart rate and symptoms such as fatigue or lightheadedness, a pacemaker is sometimes needed, says Mark A. Estes, MD, FACC, FHRS, is an American Heart Association volunteer medical expert and a Professor of Medicine in the UPMC Cardiac Electrophysiology Program in Pittsburgh, PA. "After pacemaker placement patients commonly are discharged from the hospital within 24 hours. They commonly recover sufficiently to return to work within a week."

We wish the former vice president a speedy recovery.

Facts and Resources

Your heart rhythm is the way your heart beats. Conduction is how electrical impulses travel through your heart, which causes it to beat. Some conduction disorders can cause arrhythmias, or irregular heartbeats.

A bundle branch block is a common conduction disorder.

Normally, electrical impulses travel down the right and left branches of the ventricles at the same speed. This allows both ventricles to contract simultaneously. But when there’s a “block” in one of the branches, electrical signals have to take a different path through the ventricle. This detour means that one ventricle contracts a fraction of a second slower than the other, causing an arrhythmia.

Symptoms and diagnosis

A person with bundle branch block may experience no symptoms, especially in the absence of any other problems. In such cases, bundle branch block is usually first identified by testing for some other reason, such as a routine physical. An electrocardiogram (EKG or ECG) reveals bundle branch block when it measures the heart’s electrical impulses.


Often, no treatment is required for bundle branch block, but regular monitoring is recommended. If a pacemaker is needed to help the heart beat in a regular rhythm, the small battery-operated device may be implanted. There are two parts: a generator and wires (leads).

  • The generator is a small battery-powered unit.
  • It produces the electrical impulses that stimulate your heart to beat.
  • The generator may be implanted under your skin through a small incision.
  • The generator is connected to your heart through tiny wires that are implanted at the same time.
  • The impulses flow through these leads to your heart and are timed to flow at regular intervals just as impulses from your heart's natural pacemaker would.
  • Some pacemakers are external and temporary, not surgically implanted.

How a pacemaker works

It replaces the heart's defective natural pacemaker functions.

  • The sinoatrial (SA) node or sinus node is the heart's natural pacemaker. It's a small mass of specialized cells in the top of the right atrium (upper chamber of the heart). It produces the electrical impulses that cause your heart to beat.
  • A chamber of the heart contracts when an electrical impulse or signal moves across it. For the heart to beat properly, the signal must travel down a specific path to reach the ventricles (the heart's lower chambers).
  • When the heart's natural pacemaker is defective, the heartbeat may be too fast, too slow or irregular.
  • Rhythm problems also can occur because of a blockage of your heart's electrical pathways.
  • The pacemaker's pulse generator sends electrical impulses to the heart to help it pump properly. An electrode is placed next to the heart wall and small electrical charges travel through the wire to the heart.
  • Most pacemakers have a sensing mode that inhibits the pacemaker from sending impulses when the heartbeat is above a certain level. It allows the pacemaker to fire when the heartbeat is too slow. These are called demand pacemakers.

Pacemaker Procedure Statistics

Quick Links: conduction disorderarrhythmiapacemaker, AHA Heart Disease and Stroke Statistics 2021heart.orgstroke.org and AHA/ASA news on Twitter @HeartNews

About the American Heart Association

The American Heart Association is a relentless force for a world of longer, healthier lives. We are dedicated to ensuring equitable health in all communities. Through collaboration with numerous organizations, and powered by millions of volunteers, we fund innovative research, advocate for the public’s health and share lifesaving resources. The Dallas-based organization has been a leading source of health information for nearly a century. Connect with us on heart.orgFacebookTwitter or by calling 1-800-AHA-USA1.   


For Media Inquiries and AHA/ASA Spokesperson Perspective: 214-706-1173, ahacommunications@heart.org

AHA staff: Julie Del Barto, julie.delbarto@heart.org

For Public Inquiries: 1-800-AHA-USA1 (242-8721)

heart.org and stroke.org

Follow AHA/ASA news on Twitter @HeartNews