A ventricular septal defect is basically a hole between the heart’s two lower chambers. Most are picked up in infancy, usually when a paediatrician hears a murmur during a routine check. Some shut on their own in the first couple of years. The bigger ones rarely do. That’s where the worry actually starts.

According to Dr. Prashant Bobhate, an experienced Pediatric Cardiologist in Mumbai, “An untreated VSD doesn’t just sit there quietly, the lungs keep getting hit with extra blood every beat, and by the time symptoms show up clearly, the damage in the pulmonary vessels is usually already done.”

The problem with a moderate or large VSD is plain physics. Blood keeps shunting from the higher-pressure left side into the lower-pressure right side, and over the years it’s the lungs and heart that pay the price.

• Volume overload: The left chambers handle far more blood than they were ever meant to, and they slowly stretch out, the muscle thins, and at some point the pumping just isn’t what it used to be.
• Lung pressure: That nonstop high-flow stream into the pulmonary arteries thickens the vessel walls, the arteries lose their stretchiness, and pulmonary hypertension settles in well before anyone catches on.
• Heart failure clues: Babies with large VSDs often struggle through feeds, sweat heavily during a bottle, fall behind on weight, and pick up one chest infection after another, simply because the heart can’t keep pace with what their growing body is asking for.
• Eisenmenger syndrome: This is the point of no return, lung pressures climb so high that blood actually starts flowing the wrong way across the defect, and once you reach there, closing the hole is no longer on the table.

If your child’s diagnosis is sitting in some old file and reviews have slipped, getting a fresh congenital heart disease evaluation is honestly the most important step right now.

Adults walking around with an unrepaired moderate VSD into their thirties and forties tend to deal with a different set of issues. Most of them sneak up. No drama, just slow drift.

• Arrhythmias: Years of subtle chamber stretching mess with the heart’s wiring, and atrial fibrillation, sometimes ventricular rhythms, tends to show up somewhere between the third and fifth decade.
• Endocarditis risk: The turbulent jet of blood crossing the defect makes a perfect spot for bacteria to settle, and that’s exactly why dental hygiene and antibiotic cover before certain procedures matter way more than most patients realise.
• Exercise tolerance: Patients who feel reasonably fine at rest often notice they get winded faster than friends their age on a flight of stairs, and a simple lung pressure check usually explains the gap.
• Pregnancy concerns: Women with moderate or large unrepaired VSDs face genuinely higher risks through pregnancy, and if pulmonary hypertension has already set in, the maternal risk shifts into a serious zone.

Our blog on pulmonary hypertension warning signs is worth a read if any of this is starting to sound familiar.

Dr. Prashant Bobhate works across paediatric cardiology, congenital heart disease, and pulmonary hypertension at Children’s Heart Centre, Kokilaben Hospital Andheri, and the day-to-day case mix runs from newborn echo screenings to complex adult congenital follow-ups. What patients consistently mention is how plainly the long-term picture gets put on the table at the first visit, no padding, no vague timelines, just a clear sense of where things are headed over the next five or ten years depending on the call you make today.

• Ventricular Septal Defect Overview — American Heart Association
• Long-term Outcomes of Unrepaired VSD — National Library of Medicine

The main signs are usually a big gap between upper and lower body blood pressure, weak or delayed leg pulses next to the arm pulses, babies who struggle during feeds, poor weight gain, tired legs in older kids during play, and in the sharpest cases, a newborn who crashes in the first few weeks of life once the ductus arteriosus starts to close.

“Coarctation is one of those lesions that can sit hidden for years, and the one clinical move that catches it early is simply checking leg pulses and comparing them with the arms, something still missed far more often than it really should be,” says Dr. Prashant Bobhate, Pediatric Cardiologist in Mumbai, India.

Coarctation doesn’t show up the same way at every age. What you’d spot in a crashing newborn looks nothing like what you’d pick up in a healthy-looking ten-year-old with just a murmur on routine screening.

• Weak or delayed femoral pulses: Leg pulses feeling noticeably softer than the arm pulses, or arriving a beat late, are usually the first real clue on examination.
• Arm pressure high, leg pressure low: A gap of more than 20 mmHg between upper and lower limb pressures is a strong red flag for narrowing somewhere along the aortic arch.
• Breathlessness and poor feeding in infants: Babies tire out halfway through a feed, sweat on the forehead, and gain weight slowly in a way that just doesn’t quite add up on routine paediatric review.
• Leg fatigue or cramping during play: Older kids complain of tired legs, cramps during sport or running, or a strange heaviness that eases the moment they stop, often brushed off as plain unfitness for years.

Any child showing these features really deserves a proper congenital heart disease workup, because coarctation picked up early is so much easier to manage than one found after years of quiet pressure overload on the heart.

Clinical findings raise the suspicion. Confirmation, though, always comes down to imaging, and this is really where early diagnosis quietly separates from late diagnosis when you look at long-term outcomes.

• Four-limb blood pressure measurement: Measuring pressure in both arms and both legs is the single most useful bedside test, and a real gap between upper and lower limb pressure is practically diagnostic on its own.
• Echocardiography: A 2D echo usually shows the coarctation site, gives the pressure gradient across it, and tells the clinician how well the left ventricle is coping with the extra load.
• CT or MR angiography: Cross-sectional imaging comes in when the echo isn’t clear, especially in older children, adolescents and young adults where the arch can’t always be seen properly on echo alone.
• Pulse oximetry screening in newborns: Differential saturations between the right arm and the legs can flag critical coarctation even before symptoms start, which is why newborn pulse oximetry matters so much.

Parents wanting a broader read on how critical heart lesions tend to surface in the first days of life can take a look at our piece on signs of a heart problem in a newborn baby, because spotting the pattern early really does change how much room there is to plan the next steps.

Diagnosing coarctation comes down to putting the clinical findings, blood pressure gap and imaging into one clean picture, and then making an honest call on whether this child needs catheter-based intervention, surgical repair or just careful follow-up, rather than drifting between opinions for months. Dr. Prashant Bobhate has spent over 12 years managing congenital aortic lesions across every age group, from critical neonatal presentations right through to adult patients with late-diagnosed coarctation, at the Children’s Heart Centre, Kokilaben Dhirubhai Ambani Hospital.

• Coarctation of the Aorta, MedlinePlus, U.S. National Library of Medicine — https://medlineplus.gov/ency/article/000191.htm
• Coarctation of the Aorta, American Heart Association — https://www.heart.org/en/health-topics/congenital-heart-defects/about-congenital-heart-defects/coarctation-of-the-aorta-coa

Most heart murmurs in children really aren’t the kind of thing worth panicking over, they tend to be innocent flow sounds the paediatrician catches during a routine check, and they usually fade on their own as the child grows. A smaller group, though, does hint at something structural underneath like a ventricular septal defect, a valve issue or a congenital shunt, and those are the ones a paediatric cardiologist needs to confirm or rule out on echo before anyone really starts to worry.

“Parents often panic the moment they hear the word murmur, but in most children it turns out to be a completely innocent finding, and even when it isn’t, catching it early gives us plenty of room to plan things calmly,” says Dr. Prashant Bobhate, Pediatric Cardiologist in Mumbai, India.

Not every murmur carries clinical weight. But a handful of findings on examination do push one out of the reassurance bucket and straight into echo territory.

• Loud, high-grade murmurs: Anything graded three or above on a six-point scale rarely ends up being innocent, because that kind of loudness usually means turbulent flow across something structural like a VSD or a tight valve, not the soft flow sound of a healthy heart.
• Diastolic murmurs: A murmur heard between the two heart sounds is almost always pathological, since innocent ones only ever show up in systole when the heart contracts, so a diastolic finding in a child pushes the conversation straight toward structural assessment.
• Murmurs sitting alongside worrying symptoms: Breathlessness during feeds, poor weight gain, a bluish tinge around the lips, repeated chest infections or a baby who tires out well before finishing a feed, any of these alongside a murmur point toward something real underneath.
• Murmurs with genetic or family red flags: A family history of congenital heart disease, a known syndrome like Down or Turner, or a murmur that first turns up during a viral illness and hangs around well past the recovery, each is reason enough on its own to get a proper congenital heart disease workup done.

The whole call really hinges on what the echo shows. A murmur by itself only tells you something inside the heart is making extra sound, not what’s causing it or whether the heart is coping with it.

• Innocent murmur confirmed on echo: Needs nothing beyond reassurance and a note in the records, and most of these simply fade away by early adolescence without ever needing medication or another scan.
• Small defects picked up on the side: A small VSD or a mild valve leak is usually watched rather than treated, with a repeat echo every six to twelve months, because many of these lesions either close on their own or stay small enough that they never really justify an intervention.
• Moderate to large structural defects: These shift straight into active management, where the cardiologist weighs up catheter-based closure, medical therapy or surgical repair based on the lesion itself, the child’s age, and how well the heart is coping under load.
• Murmurs with symptoms at any age: Any murmur turning up alongside breathlessness, poor growth, cyanosis or fatigue gets flagged as clinically important and worked up without delay, because symptomatic murmurs rarely turn out to be innocent once you look properly.

Parents wanting a deeper read on how structural defects actually show up in infancy, including the signs that often surface even before a murmur is picked up, can take a look at our piece on signs of a heart problem in a newborn baby, because catching the pattern early usually changes how much room there is to plan the next steps.

What really decides outcomes in a murmur case is the quality of the assessment itself, listening carefully, reading the echo against the full clinical picture, and then making a confident call on whether this is an innocent finding or something worth watching, instead of sending every family off for repeat imaging just to be safe. Dr. Prashant Bobhate has spent over 12 years evaluating paediatric heart murmurs across the full spectrum, from straightforward reassurance cases right through to complex congenital lesions, at the Children’s Heart Centre, Kokilaben Dhirubhai Ambani Hospital.

• Heart Murmurs, MedlinePlus, U.S. National Library of Medicine — https://medlineplus.gov/ency/article/003266.htm
• Heart Murmurs in Children, American Heart Association — https://www.heart.org/en/health-topics/congenital-heart-defects/symptoms–diagnosis-of-congenital-heart-defects/heart-murmurs-in-children

Congenital heart defects (CHDs) are primarily triggered by abnormal heart development within the first six weeks of pregnancy, often due to a combination of genetic factors, maternal health conditions, and environmental exposures. While many causes remain unknown, key factors include gene mutations, chromosome abnormalities, maternal infections, and substance use like smoking or alcohol.

“Most parents walk in convinced they did something wrong during the pregnancy, and honestly, in most cases the trigger was already written into the genes or tied to things nobody could have controlled,” says Dr. Prashant Bobhate, Pediatric Cardiologist in Mumbai, India.

Triggers usually sit in three broad groups, genetic, maternal, and environmental, but in a real clinic they almost never turn up one at a time. More often, two or three of them are working on a heart that has very little wiggle room during those first delicate weeks of folding and chamber formation.

Chromosomal and genetic conditions tend to leave the clearest fingerprint of all. Down syndrome, DiGeorge, Turner, Noonan, each one brings its own cardiac signature, whether that shows up as an AV canal defect, a conotruncal anomaly or aortic coarctation, because the underlying genetic code throws off the careful sequence of cardiac looping inside the embryo.

Maternal diabetes is the next big piece of the puzzle, especially when sugars run high in the first trimester. Plenty of first-time mothers are caught off guard by this, but raised blood glucose during those early weeks quietly disturbs the molecular signals that guide the heart tube into its four-chambered shape.

Infections are the third thread to watch. Rubella in the first trimester is still the textbook example, and alongside it you’ve got CMV, influenza and a handful of other viral infections picked up while the foetal heart is still forming, each one capable of leaving behind damage that only really shows up once the baby is born.

The exposure side rounds it out, alcohol, retinoic acid, lithium, thalidomide, certain older anti-seizure drugs, any of these can disturb cardiogenesis if taken during the embryonic window. That’s exactly why something as ordinary as a preconception medication review matters a good deal more than most couples tend to realise before trying for a baby.

A child found to carry any of these triggers, whether on antenatal scan or after delivery, needs a proper congenital heart disease evaluation so the lesion is mapped out accurately and the long-term plan is shaped around what that one heart genuinely needs.

Quite a few CHD cases show up in pregnancies where nothing looks wrong on paper, and those are the hardest conversations, because parents come in hoping for a clean reason and medicine, being honest, cannot always give them one.

Most isolated defects come from multifactorial inheritance, a handful of low-effect genes nudging quietly against subtle environmental factors, none of which would cause harm alone, but together just enough to tip the heart past its threshold at a vulnerable moment. De novo mutations do something similar from a different angle, a fresh mutation neither parent carries appears in the embryo for the first time and throws cardiac development off course, which is exactly why a clean family history never reads as a true guarantee.

Then there’s the plain fact that cardiac morphogenesis is intricate work, precisely timed cell migrations and tissue fusions packed into a few short weeks, so small stochastic shifts in the process can quietly leave a defect behind even when every measurable factor looked completely fine. And every year, newer genetic and epigenetic contributors keep being added into the picture, so the unknown-cause group is slowly shrinking, although it still accounts for a very real slice of paediatric heart diagnoses seen in clinic today.

Parents wanting to understand how the defect itself, whatever the trigger behind it, tends to announce itself in those first few days should read our piece on signs of a heart problem in a newborn baby, because picking up the clinical picture early genuinely changes which management options stay open.

Knowing what triggered the defect is really only half the story. What shapes the outcome is the assessment that follows, reading the echo against the clinical picture, working out whether the lesion needs surgical repair, a catheter-based device or just watchful follow-up, and then building a plan that moves with the child as they grow, instead of something copy-pasted from a textbook. Dr. Prashant Bobhate has spent over 12 years managing the full range of congenital heart disease, from antenatal diagnosis through to complex post-operative care, at the Children’s Heart Centre, Kokilaben Dhirubhai Ambani Hospital.

• Congenital Heart Defects, MedlinePlus, U.S. National Library of Medicine — https://medlineplus.gov/congenitalheartdefects.html
• Congenital Heart Defects, National Heart Lung and Blood Institute — https://www.nhlbi.nih.gov/health/congenital-heart-defects

Arrhythmia in infants and children is caused by structural heart defects, genetic ion channel disorders, heart muscle inflammation, electrolyte imbalances and in some cases no identifiable cause at all. Some are present from birth. Others develop after cardiac surgery, viral illness or as the child grows and a substrate that was always there finally declares itself under the right trigger.

“The cause matters enormously because the treatment for an arrhythmia from a repaired congenital heart is completely different to one from a channelopathy and getting that distinction right early is what stops families spending years on the wrong management,” says Dr. Prashant Bobhate, Pediatric Cardiologist in Mumbai, India.

The cause varies significantly by age, cardiac history and whether the heart is structurally normal or not.

• Congenital heart disease: Structural defects and post-surgical scar tissue create arrhythmia substrates in chambers that were never built to manage the pressures and volumes they ended up carrying across years of abnormal haemodynamics.
• Channelopathies: Long QT syndrome, Brugada syndrome and CPVT are genetic ion channel disorders that leave the heart structurally normal on echo but electrically unstable enough to trigger ventricular fibrillation under specific physiological conditions.
• Myocarditis: Viral inflammation of the heart muscle disrupts normal conduction and creates zones of electrical instability that persist for months after the child looks and feels completely well again.
• Post-surgical substrate: Scar tissue from atrial and ventricular incisions, patches and suture lines acts as the anatomical substrate for macro re-entrant arrhythmias including incisional atrial flutter that can develop years after a technically successful repair.

Every child with a documented or suspected arrhythmia needs a systematic assessment and pediatric arrhythmia evaluation maps the structural, electrical and genetic picture before any management decision is made.

Newborn arrhythmias have distinct causes that differ substantially from those seen in older children and each carries its own urgency and treatment path.

• Accessory pathways: WPW and other accessory pathway tachycardias are among the most common causes of SVT in infants and the very fast rates they generate can cause heart failure within hours in a baby whose parents had no idea anything was wrong.
• Congenital heart block: Maternal anti-Ro and anti-La antibodies cross the placenta and damage the fetal AV node causing complete heart block that needs pacemaker implantation in symptomatic neonates who can’t sustain adequate cardiac output at the slow ventricular rate.
• Metabolic causes: Hypoglycaemia, hypocalcaemia and hyperkalaemia in sick neonates alter the electrical environment of the heart enough to produce rhythm disturbances that resolve completely once the metabolic abnormality is corrected without any antiarrhythmic treatment.
• Idiopathic neonatal SVT: Many infants develop SVT in the first months of life with no identifiable structural genetic or metabolic cause and while these often resolve by twelve months the initial presentation can be dramatic enough to need emergency cardioversion.

Parents wanting to understand how cardiac abnormalities including arrhythmia substrates are detected in the newborn period before any symptomatic episode occurs should read this piece on newborn pulse oximetry heart screening because early detection changes what management options are available before a rhythm problem declares itself with a frightening episode.

Finding the cause of arrhythmia in a child means reading the ECG in context, interpreting the Holter against the clinical history, deciding whether the echo is enough or whether genetic testing changes the management and putting all of that together into a plan that matches what this specific child’s rhythm problem actually requires. Not a protocol. A real assessment built around that one child. Dr. Prashant Bobhate has spent over 12 years managing paediatric arrhythmia across its full causal spectrum from structural post-surgical substrates through channelopathies through neonatal accessory pathway tachycardias at the Children’s Heart Centre, Kokilaben Dhirubhai Ambani Hospital.

• Arrhythmia, MedlinePlus, U.S. National Library of Medicine — https://medlineplus.gov/arrhythmia.html
• Arrhythmia, National Heart Lung and Blood Institute — https://www.nhlbi.nih.gov/health/arrhythmias