Mitral Regurgitation in Children

Cardiology

Clinicals - History

Fact Explanation
Children with minor degrees of mitral regurgitation are asymptomatic The nature and severity of symptoms in mitral regurgitation (MR) relates to, etiology, rate of onset and progression, left ventricle (LV) function, pulmonary artery pressure and presence of preexisting valvular/myocardial diseases

Children with mild disease may be asymptomatic with out complications until the second or third decade of life.
Children with minor degrees of mitral regurgitation are asymptomatic
The nature and severity of symptoms in mitral regurgitation (MR) relates to, etiology, rate of onset and progression, left ventricle (LV) function, pulmonary artery pressure and presence of preexisting valvular/myocardial diseases

Children with mild disease may be asymptomatic with out complications until the second or third decade of life.
Fatigue In MR the blood in the left ventricle re enters to the left atrium during the systole through the incompetent mitral valve. This causes reduction of blood volume enters to the aorta causing low cardiac out put. This condition manifest as fatiguability.
Thought fatigue may be reported in children they can tolerate more severe mitral regurgitation better than adults.
Fatigue
In MR the blood in the left ventricle re enters to the left atrium during the systole through the incompetent mitral valve. This causes reduction of blood volume enters to the aorta causing low cardiac out put. This condition manifest as fatiguability.
Thought fatigue may be reported in children they can tolerate more severe mitral regurgitation better than adults.
Dyspnoea This is occur due to the pulmonary venous congestion. Due to the increased blood volume in left atrium( due to regurgitated blood) pressure in pulmonary circulation will increase.This can ultimately leads to pulmonary hypertension and once it develops, complaints such as dyspnoea with light activity become more prominent. Dyspnoea
This is occur due to the pulmonary venous congestion. Due to the increased blood volume in left atrium( due to regurgitated blood) pressure in pulmonary circulation will increase.This can ultimately leads to pulmonary hypertension and once it develops, complaints such as dyspnoea with light activity become more prominent.
Palpitations Palpitations can develop due to either increases stroke volume or if the MR is complicated with atrial fibrillation( due to the chronic atrial dilatation). Palpitations
Palpitations can develop due to either increases stroke volume or if the MR is complicated with atrial fibrillation( due to the chronic atrial dilatation).
Orthopnoea Pulmonary oedema with pulmonary venous congestion will develop this symptom. Number of pillows patient is using due to uncomfortably on lying down will give an idea of presence of this symptom. Orthopnoea
Pulmonary oedema with pulmonary venous congestion will develop this symptom. Number of pillows patient is using due to uncomfortably on lying down will give an idea of presence of this symptom.
Development of shortness of breath, swelling of feet and ankles, sensation of feeling the heart beat, fatigue, weakness, fainting Due to increased pressure in the pulmonary circulation right ventricular workload will increase resulting right heart failure with the time. This will give these symptoms together. Development of shortness of breath, swelling of feet and ankles, sensation of feeling the heart beat, fatigue, weakness, fainting
Due to increased pressure in the pulmonary circulation right ventricular workload will increase resulting right heart failure with the time. This will give these symptoms together.
Growth and development of the child With severe mitral regurgitation, children may experience limited growth and failure to thrive. This is due to the MR it self causing abnormalities in the circulation and may be due to the recurrent infections/ recurrent hospital admissions/ surgeries associated with the condition. Growth and development of the child
With severe mitral regurgitation, children may experience limited growth and failure to thrive. This is due to the MR it self causing abnormalities in the circulation and may be due to the recurrent infections/ recurrent hospital admissions/ surgeries associated with the condition.
Past history of mitral valve disease Mitral valve prolapse is a diagnosed cause for the development of MR with the time. So the early diagnosis of mitral prolapse will helpful in identifying the cause. Mitral valve prolapse is the most common valvular abnormality(affect 2-6%) Past history of mitral valve disease
Mitral valve prolapse is a diagnosed cause for the development of MR with the time. So the early diagnosis of mitral prolapse will helpful in identifying the cause. Mitral valve prolapse is the most common valvular abnormality(affect 2-6%)
Past history of rheumatic heart disease or symptoms of joint swelling /pain, rash, fever Carditis caused by rheumatic heart disease can result in MR. Past history of rheumatic heart disease or symptoms of joint swelling /pain, rash, fever
Carditis caused by rheumatic heart disease can result in MR.
Past history of infective endocarditis or symptoms of fever for long duration, rash, passage of blood with urine, fatiguability, weakness with long term injections( if seek medical advice) Infective endocarditis is an etiological factor for the development of MR. Past history of infective endocarditis or symptoms of fever for long duration, rash, passage of blood with urine, fatiguability, weakness with long term injections( if seek medical advice)
Infective endocarditis is an etiological factor for the development of MR.

Clinicals - Examination

Fact Explanation
Vital signs, normal in mild regurgitation. Heart and respiratory rates increase with increasing severity Patients with mild disease will be asymptomatic and symptoms and signs will appear with the increasing severity of the MR. Vital signs, normal in mild regurgitation. Heart and respiratory rates increase with increasing severity
Patients with mild disease will be asymptomatic and symptoms and signs will appear with the increasing severity of the MR.
Pulse characterized in severe disease as having a small volume with a sharp upstroke. Irregularly irregular pulse can be seen in atrial fibrillation Rate, rhythm, volume and character of the pulse should be check as it gives and idea of peripheral circulation as well as cardiac function. Pulse characterized in severe disease as having a small volume with a sharp upstroke. Irregularly irregular pulse can be seen in atrial fibrillation
Rate, rhythm, volume and character of the pulse should be check as it gives and idea of peripheral circulation as well as cardiac function.
Cardiac apex displaced to left and apical impulse can be felt Due to cardiomegaly a displaced hyperdynamic apex beat can be palpable.

Apical impulse, a left atrial lift is a second impulse resulting from the increased volume with regurgitated blood into the left atrium during systole. Second impulse should be felt with second heart sound. This sign is most helpful in thin children. In more advanced disease, a double impulse is felt.
Cardiac apex displaced to left and apical impulse can be felt
Due to cardiomegaly a displaced hyperdynamic apex beat can be palpable.

Apical impulse, a left atrial lift is a second impulse resulting from the increased volume with regurgitated blood into the left atrium during systole. Second impulse should be felt with second heart sound. This sign is most helpful in thin children. In more advanced disease, a double impulse is felt.
Signs in heart sounds are normal/Soft first heart sound, splitting of second heart sound, presence of third heart sound and loud second heart sound On auscultation first heart sound is found to be slightly diminished due to mitral valve incompetence.

Splitting of second heart sound is due to volume over load in right ventricle causing delayed closure and reduced cardiac output from left atrium causing early closure of aortic valve.

Severe will associated wit third heart sound
is occur due to increased ventricular filling.

Pulmonary component of the second heart sound will be more prominent/ louder with development pulmonary hypertension (increased pressure in pulmonary circulation increases the pressure difference in between pulmonary artery and right ventricle).
Signs in heart sounds are normal/Soft first heart sound, splitting of second heart sound, presence of third heart sound and loud second heart sound
On auscultation first heart sound is found to be slightly diminished due to mitral valve incompetence.

Splitting of second heart sound is due to volume over load in right ventricle causing delayed closure and reduced cardiac output from left atrium causing early closure of aortic valve.

Severe will associated wit third heart sound
is occur due to increased ventricular filling.

Pulmonary component of the second heart sound will be more prominent/ louder with development pulmonary hypertension (increased pressure in pulmonary circulation increases the pressure difference in between pulmonary artery and right ventricle).
Murmur is a pansystolyc murmur( blowing and high pitched) heard best at the apex and left sternal edge and it radiates to left axilla. First heart sound is merges with the murmur extending to the second heart sound. Murmur occurs due to the alteration in the blood flow with the valvular abnormality. little correlation is noted with intensity of murmur with severity of MR. Murmur is a pansystolyc murmur( blowing and high pitched) heard best at the apex and left sternal edge and it radiates to left axilla. First heart sound is merges with the murmur extending to the second heart sound.
Murmur occurs due to the alteration in the blood flow with the valvular abnormality. little correlation is noted with intensity of murmur with severity of MR.
Lung auscultation for crepitations Pulmonary venous congestion causes crepitations in bilateral lung bases. Lung auscultation for crepitations
Pulmonary venous congestion causes crepitations in bilateral lung bases.
Bi lateral ankle oedema, elevated jugular venous pressure, tender hepatomegallly. These are signs of right heart failure. Bi lateral ankle oedema, elevated jugular venous pressure, tender hepatomegallly.
These are signs of right heart failure.

Investigations - Diagnosis

Fact Explanation
ECG To see evidence of left atrial hypertrophy, left ventricular hypertrophy
or evidence of atrial fibrillation.
ECG
To see evidence of left atrial hypertrophy, left ventricular hypertrophy
or evidence of atrial fibrillation.
Chest X ray Enlargement of the left atrium and left ventricle can be seen.
Pulmonary venous congestion can be seen around bilateral hilar areas.
If patient present wit acute onset dyspnoea due to pulmonary oedema, it also visible.
Chest X ray
Enlargement of the left atrium and left ventricle can be seen.
Pulmonary venous congestion can be seen around bilateral hilar areas.
If patient present wit acute onset dyspnoea due to pulmonary oedema, it also visible.
Echocardiography Will reveal the structure and function of the heart.It will show, dilated left atrium and left ventricle, dynamic left ventricle can be seen unless myocardial dysfunction is prominent.
Stuctural abnormalities of the mitral valve can be seen if endocarditis is associated with vegitations can also be seen.
Echocardiography
Will reveal the structure and function of the heart.It will show, dilated left atrium and left ventricle, dynamic left ventricle can be seen unless myocardial dysfunction is prominent.
Stuctural abnormalities of the mitral valve can be seen if endocarditis is associated with vegitations can also be seen.
Doppler studies This will assess the defects and quantities of the mitral regurgitation using the flow of the blood inside the heart. Doppler studies
This will assess the defects and quantities of the mitral regurgitation using the flow of the blood inside the heart.
Cardiac catherization During cardiac catheterization, dilated left atrum and left ventricle and pulmonary hypertension can be seen. Cardiac catherization
During cardiac catheterization, dilated left atrum and left ventricle and pulmonary hypertension can be seen.

Investigations - Management

Fact Explanation
Echocardiography This is useful in follow up to see the structure and function with the time, and to see the improvement after surgery. Echocardiography
This is useful in follow up to see the structure and function with the time, and to see the improvement after surgery.
Blood culture This is useful if the aetiology is suspected as infective endocarditis to see the evidence of bacteraemia. Blood culture
This is useful if the aetiology is suspected as infective endocarditis to see the evidence of bacteraemia.
Full Blood count(FBC) Full blood count useful in assessing the haemoglobin level of the patient, as anaemia can worsen cardiac symptoms due to poor perfusion.
WBC level will useful in assessing any coexisting infections which should be treated quickly.
Platelet count will be useful in assessing any bleeding tendency before invasive procedures like cardiac catheterisation.
Full Blood count(FBC)
Full blood count useful in assessing the haemoglobin level of the patient, as anaemia can worsen cardiac symptoms due to poor perfusion.
WBC level will useful in assessing any coexisting infections which should be treated quickly.
Platelet count will be useful in assessing any bleeding tendency before invasive procedures like cardiac catheterisation.
APTT, PT, INR These tests which use for assessing the clotting profile important before invasive procedures/ surgeries .
If the patient has developed atrial fibrillation and he is on warfarin this is useful in adjusting the dose.
APTT, PT, INR
These tests which use for assessing the clotting profile important before invasive procedures/ surgeries .
If the patient has developed atrial fibrillation and he is on warfarin this is useful in adjusting the dose.
Echocardiography This can assess the level of MR( mild, moderate, severe) and progress of the condition with the time. Echocardiography
This can assess the level of MR( mild, moderate, severe) and progress of the condition with the time.

Management - Supportive

Fact Explanation
Dietary modifications If the patient is having chronic symptomatic MR/ left ventricular dysfunction, reduction of salt intake is recommended. And also need to take healthy diet with low fats.
Too much caffeine will worsen the arrhythmia, so especially if the patient is having atrial fibrillation better to avoid caffeine containing foods like- coffee, soft drinks .
Dietary modifications
If the patient is having chronic symptomatic MR/ left ventricular dysfunction, reduction of salt intake is recommended. And also need to take healthy diet with low fats.
Too much caffeine will worsen the arrhythmia, so especially if the patient is having atrial fibrillation better to avoid caffeine containing foods like- coffee, soft drinks .
maintaing ideal body weight according to the height and do regular physical exercise As the obesity can cause symptoms like shortness of breath it can interfere the assessment of the MR.Obesity is also associated with several morbidity conditions. In a obese patient facing a surgery there can be, anaesthetic problems, wound healing and post surgical complains like deep vein thrombosis can occur, so maintaining ideal body weight is very important. maintaing ideal body weight according to the height and do regular physical exercise
As the obesity can cause symptoms like shortness of breath it can interfere the assessment of the MR.Obesity is also associated with several morbidity conditions. In a obese patient facing a surgery there can be, anaesthetic problems, wound healing and post surgical complains like deep vein thrombosis can occur, so maintaining ideal body weight is very important.
Prophylactic antibiotics for the prevention of recurrence shuld be given to patients. Screen for rheumatic fever( if the primary cause is that) and prophylactically treat other siblings with penicillin to prevent rheumatic fever. This is one of the most important steps in prevention. Prophylactic antibiotics for the prevention of recurrence shuld be given to patients. Screen for rheumatic fever( if the primary cause is that) and prophylactically treat other siblings with penicillin to prevent rheumatic fever.
This is one of the most important steps in prevention.
Dental care and dental surgeries under antibiotic coverage Dental hygiene should be maintain. Tooth brushing should be done correctly, at least twice a day, reduce sweet intake, after eating a sweet food wash the mouth, go to a dental surgeon at least once in 3 months and take early treatment for dental caries

Do dental surgeries under prophylactic antibiotic coverage to prevent occurrence of infective endocarditis, as it can cause bacteraemia and can cause systemic embolization.
Dental care and dental surgeries under antibiotic coverage
Dental hygiene should be maintain. Tooth brushing should be done correctly, at least twice a day, reduce sweet intake, after eating a sweet food wash the mouth, go to a dental surgeon at least once in 3 months and take early treatment for dental caries

Do dental surgeries under prophylactic antibiotic coverage to prevent occurrence of infective endocarditis, as it can cause bacteraemia and can cause systemic embolization.
Regular follow up regular follow up is needed by a cardiologist to look for any evidence of worsening symptoms and development of complications

follow up frequency will be individualized according to the patients condition. Electrocardiogram is useful in follow up.

If the patient is having high blood pressure or is in risk of developing hypertension need to do regular blood pressure monitoring should be done.
Regular follow up
regular follow up is needed by a cardiologist to look for any evidence of worsening symptoms and development of complications

follow up frequency will be individualized according to the patients condition. Electrocardiogram is useful in follow up.

If the patient is having high blood pressure or is in risk of developing hypertension need to do regular blood pressure monitoring should be done.

Management - Specific

Fact Explanation
medical management Diuretics and Vasodilators Patient should be given afterload-reducing agents (eg; vasodilators) as high afterload can worsen the degree of regurgitation. Angiotensin converting enzyme inhibitors can be used.
Diuretics are helpful in maintaining the forward cardiac output in persons who are having MR with symptoms and LV dysfunction
medical management Diuretics and Vasodilators
Patient should be given afterload-reducing agents (eg; vasodilators) as high afterload can worsen the degree of regurgitation. Angiotensin converting enzyme inhibitors can be used.
Diuretics are helpful in maintaining the forward cardiac output in persons who are having MR with symptoms and LV dysfunction
medical management Digoxin, Beta-blockers, Calcium channel blockers and Anticoagulants If the patient's condition is complicated with atrial fibrillation digoxin, beta-blockers, calcium channel blockers( in maintaining the normal ventricular function) and anticoagulant, warfarin( to prevent clot formation and embolization) treatment will be helpful.

Anticoagulation also useful following mitral valve replacement surgery.
medical management Digoxin, Beta-blockers, Calcium channel blockers and Anticoagulants
If the patient's condition is complicated with atrial fibrillation digoxin, beta-blockers, calcium channel blockers( in maintaining the normal ventricular function) and anticoagulant, warfarin( to prevent clot formation and embolization) treatment will be helpful.

Anticoagulation also useful following mitral valve replacement surgery.
medical management Antiboiotics If MR is due to infective endocarditis/ rheumatic fever, primary cause should be treated with antibiotics.
Also prophylaxis treatment is useful prior to dental procedures.
medical management Antiboiotics
If MR is due to infective endocarditis/ rheumatic fever, primary cause should be treated with antibiotics.
Also prophylaxis treatment is useful prior to dental procedures.
Surgical treatment Mitral valve repair and replacement In severe MR this is the treatment option especially if there is LV systolic dysfunction in severe MR with an ejection fraction of 60% or less, an end-systolic dimension of 40 mm or greater and development of other complications like pulmonary hypertension, atrial fibrillation Surgical treatment Mitral valve repair and replacement
In severe MR this is the treatment option especially if there is LV systolic dysfunction in severe MR with an ejection fraction of 60% or less, an end-systolic dimension of 40 mm or greater and development of other complications like pulmonary hypertension, atrial fibrillation

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