How does the heart beat?
"Normally a heartbeat is started by an electrical impulse located at the top of the heart," says Doylestown Health electrophysiologist Robert Sangrigoli, MD. "The bottom of the heart must receive this impulse or signal in order to complete the heartbeat."
Abnormal heart rhythms (arrhythmias) are caused by problems with the electrical system that regulates the steady heartbeat. The electrical impulses may happen too fast, too slowly, or irregularly.
Heart rhythm problems can cause a few types of symptoms because the heart isn't beating regularly or may not be pumping blood as well as normal. Some of these symptoms include palpitations, lightheadedness, fainting, and shortness of breath. People with arrhythmias might need a pacemaker.
What is a pacemaker?
A pacemaker uses electrical pulses to prompt the heart to beat at a normal rate. It can speed up a slow heart rhythm, control a fast heart rhythm, and coordinate the chambers of the heart. Implanted near the collarbone, the pacemaker's leads (wires) are threaded through a blood vessel into the heart.
"Pacemakers can help patients who have two types of issues: those who have problems with the initial impulse at the top of the heart, and those who have problems with the ability of an impulse to make its way to the bottom of the heart," adds Dr. Sangrigoli.
What is the His Bundle?
The bundle of His is a part of the electrical system of the heart.
Dr. Sangrigoli explains, "Normally an electrical impulse traveling from top-to-bottom must enter a specialized electrical highway located at the middle of the heart called the His Bundle, which refers to a bundle of electrical fibers connecting the top and bottom of the heart.
Once the impulse enters this highway it can effectively spread to the bottom of the heart to complete a normal heartbeat. This electrical sequence from top-to-middle-to-bottom generates the most efficient heartbeat possible."
What is His Bundle pacing?
Standard pacemakers have traditionally bypassed the middle portion of the heart (the His Bundle) by including a pacing wire or lead at the top of the heart and one at the bottom of the heart.
"The electrical sequence generated by standard pacemakers is then top-to-bottom, bypassing the middle portion of the heart. This generates a more 'artificial' sequence of beating and a less efficient heartbeat. This is a particular problem in patients who may already have compromised heart function," says Dr. Sangrigoli.
He adds, "His Bundle pacing is a novel technique where we move the bottom wire or pacing lead to the middle of the heart placing this lead directly into the His Bundle. This allows for a more natural or physiologic electrical pattern and a more normal heartbeat.
Several studies have recently demonstrated that this technique can improve mechanical function of the heart because it restores the top-to-middle-to-bottom sequence."
Who can benefit from His Bundle pacing?
His Bundle pacing primarily benefits patients with electrical problems at the middle portion of the heart. This could include patients with "heart block," which refers to a situation where signals may enter the middle portion of the heart but never leave. The lower chambers of the heart (ventricles) then beat too slowly, decreasing the amount of oxygen that gets to the body and brain.
"His Bundle pacing can also help patients with something we call 'bundle branch block,' which is when signals enter and exit the middle portion of the heart more slowly than normal," says Dr. Sangrigoli. "Several studies have also suggested this pacing technique may benefit patients with a weakened heart, a condition called heart failure.
The procedure adds minimal time to a standard pacemaker implantation and adds no additional risk. Just like with standard pacemakers, an overnight hospital stay should be expected."
How might this technique change the way pacemakers are used?
"It's too early to know for sure, but emerging data suggests this may be the preferred pacing technique in all patients, becoming the new standard for permanent pacemaker implantations," notes Dr. Sangrigoli. "More to come on this as we await larger clinical trial results.
Adding this novel pacing technique to our already robust pacing and arrhythmia ablation program is one more example of how Doylestown Health continues to provide cutting-edge clinical care in the field of electrophysiology."
About Doylestown Health's Heart & Vascular Services
Expert cardiologists and cardiac surgeons assist patients and physicians with managing risk factors for heart disease, offer advanced treatment options and provide outstanding emergency cardiac care. Doylestown Hospital’s accredited Chest Pain Center is fully prepared to treat cardiac emergencies around the clock, focusing on rapid diagnosis and effective treatment. The multidisciplinary team at the Woodall Center for Heart and Vascular Care is dedicated to providing the highest level of quality care and patient safety.
