A two-month-old baby, Mikey Oliveri, is now thriving after receiving the world’s smallest pacemaker late last year. Born prematurely, weighing just 2.5 kg, Mikey was diagnosed with heart block, a life-threatening condition that disrupts the heart’s electrical system. Thanks to an innovative tiny pacemaker, doctors were able to save his life.

Early Diagnosis: A Life-Saving Intervention

Mikey’s mother, Sarah Oliveri, had a healthy pregnancy until her 20-week scan revealed signs of heart block, a rare congenital heart condition. This disorder prevents electrical signals from reaching the lower chambers of the heart, causing a dangerously slow or irregular heartbeat.

Doctors at Hassenfeld Children’s Hospital at NYU Langone began monitoring Mikey’s heart rate in utero, which stayed around 50 beats per minute—far below the normal newborn heart rate of 130-150 bpm.

“After delivery on December 5, Mikey’s heart rate dropped below 50, and signs of distress emerged,” said Dr. Reina Tan, Mikey’s pediatric cardiologist. “We determined he would need a pacemaker as soon as possible.”

A Tiny Device That Saved a Life

Typically, babies requiring pacemakers need to weigh at least 3-3.5 kg before receiving a standard device. Since Mikey was too small and could not wait, doctors had to find an alternative solution.

Dr. Tan and her team turned to Medtronic’s Micra leadless pacemaker—a tiny device no bigger than a large vitamin capsule, weighing about as much as a penny.

How did they make it work?
The device was specially adapted for Mikey, allowing it to function as a pacemaker generator after pacing leads were attached to his heart.

A rare procedure in newborns
While pacemakers are common in adults, they are rarely implanted in infants. Only 1 in 20,000 children are born with heart block, and not all require a pacemaker.

“This is a unique situation,” Dr. Tan explained. “Mikey is only 1 of 52 babies in the United States to receive this kind of pacemaker. He’s the first baby at NYU Langone and the first in the tri-state area.”

After two weeks of post-surgery care, Mikey was discharged and has been recovering well, leading a normal baby life.

Understanding Heart Block: Causes, Symptoms, and Treatment

What is Heart Block?

Heart block occurs when the electrical signals in the heart do not transmit properly between the upper and lower chambers. This can result in:
Slow or skipped heartbeats
Low blood flow to the body
In severe cases, heart failure

While some cases of heart block are present at birth, most people develop it later in life due to various health conditions.

Causes of Heart Block

Heart block can be caused by:
Heart attack or coronary artery disease
Congenital heart defects (from birth)
Heart damage during surgery
Side effects of medications (such as beta blockers)
Autoimmune diseases
Obstructive sleep apnea
Genetic disorders

Signs and Symptoms of Heart Block

Chest pain
Fatigue and weakness
Shortness of breath
Palpitations (irregular heartbeat)
Rapid breathing
Dizziness and fainting
Nausea

A Medical Milestone for Infant Cardiac Care

Mikey Oliveri’s story is a groundbreaking milestone in infant cardiac care. With only 52 babies in the U.S. receiving this kind of pacemaker, it showcases the advancements in medical technology that are now saving lives even in the most fragile newborns.

As Mikey continues to grow, his case serves as hope for other infants diagnosed with congenital heart conditions, proving that size doesn’t limit survival when medical innovation steps in.