When something is wrong with a young person’s heart, it rarely announces itself clearly.
There may not be no dramatic movie moment — no obvious chest-clutching or alarming symptoms.
Instead, cardiac issues in children tend to whisper. They show up quietly, wrapped in what might masquerade as normal childhood behavior: a child who tires faster than usual, a moment of dizziness, a complaint of “my chest feels funny.”

Most parents don’t think “heart problem.”
And why would they? Children are supposed to be resilient, energetic, endlessly adaptable.

Yet the research — and what Dr. Patrick Flynn sees every week in his practice — tells a different story: many cardiac conditions in kids are silent before something serious occurs.
This is why early, preventive screening has become one of the most important tools to protect active children and young athletes.

Here are the seven subtle signs that deserve a closer look.

1. When a Child Tires Faster Than They Should

Children naturally fluctuate in energy. But when a once-active child suddenly struggles to keep up, asks to sit out more often, or appears drained after activities they used to enjoy, it can be a sign that the heart is working harder than it should.

Parents often attribute it to growth spurts or “a lazy day.”
But a noticeable or persistent drop in stamina is worth paying attention to.

2. Chest Discomfort That Appears Only With Effort

Chest pain in children is common — and usually harmless.
What matters is when it occurs.

Pain that appears during running, intense play, or competitive sports can indicate something different. It may come in the form of tightness, heaviness, or pressure that the child can’t quite describe. They just know something feels wrong.

If chest discomfort seems linked to exertion, it’s time to look deeper.

3. A Fainting Episode That Doesn’t Sit Right

Fainting is one of the most easily dismissed symptoms in pediatrics.
Many parents think: “They were dehydrated,” or “They got up too fast.”

But fainting — or even the sensation of almost fainting — during or immediatly after physical activity is a red flag that pediatric cardiologists take extremely seriously. It can signal rhythm abnormalities that need immediate evaluation.

4. “My Heart Feels Weird” — The Palpitation Confession

Kids rarely use the word palpitations.
Instead, they say:

• “My heart is beating funny.”
• “It feels like it’s jumping.”
• “It’s going too fast.”

These fleeting episodes are easy to ignore — but they are one of the most reliable early clues that something more is happening electrically inside the heart.

5. Shortness of Breath That Isn’t Asthma

Breathlessness is often mistaken for asthma, especially in sporty kids.
But if inhalers don’t help, or if the child struggles at a level that seems disproportionate to the activity, the cause may not be respiratory at all — it may be cardiac.

Parents often describe this as:
“He gets out of breath faster than the other kids.”
or
“She needs longer to recover after running.”

This imbalance can signal reduced function of the heart muscle or an underlying structural issue.

6. Blue Lips, Sudden Paleness, or Sweating That Feels Excessive

Most children flush or sweat when they play.
But when they suddenly look pale, bluish around the lips, or drenched in sweat in a way that doesn’t match the moment — especially during exertion — it may be the body trying to compensate for a cardiac imbalance.

These signs can be subtle. They often appear in photos, during a race, or after climbing stairs.

Pay attention if they appear more than once.

7. A Family History That Raises an Eyebrow

Sometimes the most important symptom never shows up in the child —
it’s in the family tree.

If a relative experienced:

• sudden unexplained death before age 50 (including unexpected drowning in a good swimmer, or fatal car accident by a good drive)
• an aortic aneurysm,
• a heart attack before age 50
• unexplained fainting,
• known arrhythmias,

then screening becomes not just important — but proactive and protective.

You don’t need to wait for a symptom to appear before taking action.

The Good News: Early Screening Works

The purpose of pediatric cardiac screening isn’t to alarm parents — it’s to empower them.
Most conditions, when identified early, can be treated, monitored, and managed long before they ever become dangerous.

A preventive cardiac screening with Dr. Flynn typically includes:

• a child-friendly ECG,
• an echocardiogram when needed,
• a full risk assessment for sports,
• and clear guidance for parents.

It’s simple, quick, and — most importantly — it brings peace of mind.
The goal is NOT to take young people off the field - or out of the pool, or off the dance floor - unnecessarily. It's to get them back in the game with confidence.

If You’re Unsure… Trust Your Instinct

Parents know their children better than anyone.
If something feels off — even slightly — it’s always worth checking.

Preventive care is not about fear.
It’s about confidence, clarity, and safety for the children we love.

Ready to take the next step?

Dr. Patrick Flynn is now offering priority screening slots for young athletes and active children.

• Book a screening and call us at +1 917 526 9742
• Download the Parent Safety Checklist
• Register for the upcoming webinar: Keeping Young Athletes Safe in 2026 here

Your child’s heart deserves the same attention as their training, their schoolwork, and their wellbeing.
This simple step can make all the difference.

About Dr. Patrick A. Flynn
Dr. Patrick Flynn is a New York–based Pediatric Cardiologist specializing in preventive cardiac screening, athlete safety, and early detection of heart conditions in children and adolescents. He is known for his calm, family-centered approach and for helping young athletes return to sports with confidence and clarity. Dr. Flynn provides comprehensive evaluations including ECG and echocardiography, with a focus on clear communication and personalized care.

Practice Location
Avalon Pediatric Cardiology
248 East 73rd Street
New York, NY 10021

Dr. Flynn is accepting new patients for preventive heart screenings and sports clearance.