Presentation depends on heart anatomy and associated abnormalities: anomalies of other valves, coarctation of the aorta, transposition of the great arteries, patent ductus arteriosus or other systemic-pulmonary circulation shunts. The pulmonary artery may be hypoplastic and the abnormalities are sometimes diagnosed in utero [1].

During childhood, the physician will notice dyspnea, central cyanosis, weak peripheral pulses and heart failure signs. Symptoms may set in early and may be severe, therefore the baby needs to be delivered in a center that can immediately address the condition, if the diagnosis is known before birth [2]. The child grows normally in utero, but failure to thrive is noticed after delivery. Cyanosis sets in soon if the foramen ovale is small or closed, but may be absent in the newborn period. The closure of the ductus arteriosus marks a turning point in the child's presentation. He or she may become pale, may exhibit tachypnea, respiratory distress, lethargy and oliguria at this time. Additional findings include those of cardiogenic shock, like hypothermia, tachycardia, anuria and hepatosplenomegaly. A diastolic rumble over the entire precordial area or a high-pitched holosystolic murmur over the inferior portion of the left sternal border may be auscultated, but their presence is not mandatory [3]. The precordium may be hyperactive.

After the malformation has been surgically addressed, the clinical examination should focus on the cardiovascular and neurologic symptoms, because patients often exhibit seizures [4]. Stroke and intracranial hemorrhage are also possibilities [5], as are phrenic and recurrent laryngeal nerve injury [6].

Blood workup should include a complete cell blood count with differential, in order to exclude sepsis, that can cause similar symptoms. Hemoglobin levels should be investigated, because anemia can also cause high-output congestive heart failure. A constant characteristic of mitral valve atresia is severe metabolic acidosis, that often becomes worse after oxygen administration. Acid-base status, lactic acid and electrolyte levels measurement are mandatory. Renal failure secondary to heart failure is assessed by blood urea nitrogen and creatinine levels. Transient hepatic cytolysis is sometimes observed. Arterial oxygen and carbon dioxide determination help set mechanical ventilation parameters.

A hypoplastic left ventricle causes right axis deviation on the electrocardiogram. Right ventricular hypertrophy and right atrial enlargement patterns, as well as ST-T wave modifications can sometimes be recognized.

Thoracic radiography shows cardiomegaly and increased pulmonary vascular markings, but echocardiography helps to achieve the final diagnosis. This method accurately delineates the morphology of the mitral valve and the presence of an anterograde or retrograde flow, the function of the aortic valve, the size of both ventricles and the presence of interatrial and interventricular communications and their restrictive or non-restrictive character. The examiner is able to describe the position, the dimensions and the origin of the great arteries. Tricuspid regurgitation is considered to be a preoperative risk factor.

An abdominal ultrasound examination may describe polysplenia, asplenia or a normal spleen. Cerebral abnormalities should be investigated using a head ultrasound [7].

Cardiac catheterization is necessary in cases where echocardiography cannot answer all the questions. It can also be used in order to measure saturation in all four cardiac chambers, chamber pressures and pulmonary vascular resistance. The presence of aortopulmonary collateral vessels should also be investigated on that occasion [8].

Cytogenetic abnormalities and heterozygous mutations have been described by several authors [9] [10]. If suspicion is raised, a karyotype analysis may be performed.

Treatment for mitral atresia typically involves surgical intervention to correct the heart's structural abnormalities. The specific approach depends on the individual patient's anatomy and associated defects. Common procedures include the Norwood operation, Glenn procedure, and Fontan procedure, which are staged surgeries designed to improve blood flow and heart function. In some cases, heart transplantation may be considered. Medical management may also include medications to support heart function and manage symptoms.

The prognosis for individuals with mitral atresia varies based on the severity of the condition and the success of surgical interventions. Advances in surgical techniques have significantly improved outcomes, allowing many patients to lead relatively normal lives. However, lifelong follow-up with a cardiologist is essential to monitor heart function and address any complications that may arise.

Mitral atresia is a congenital condition, meaning it is present at birth. The exact cause is not well understood, but it is believed to result from abnormal development of the heart during fetal growth. Genetic factors may play a role, although most cases occur sporadically without a clear familial pattern. Environmental factors during pregnancy have also been suggested as potential contributors.

Mitral atresia is a rare condition, with an estimated incidence of less than 1 in 10,000 live births. It affects both males and females equally and can occur in any ethnic group. Due to its rarity, it is often managed at specialized centers with expertise in congenital heart defects.

In mitral atresia, the absence or underdevelopment of the mitral valve prevents normal blood flow from the left atrium to the left ventricle. This leads to increased pressure in the left atrium and pulmonary circulation, causing pulmonary congestion and reduced oxygenation of blood. The heart must compensate by relying on other pathways for blood flow, often involving associated defects such as atrial septal defects or patent ductus arteriosus.

Currently, there are no known methods to prevent mitral atresia, as it is a congenital condition. However, prenatal care and early detection through fetal echocardiography can help in planning appropriate management strategies before and after birth. Genetic counseling may be beneficial for families with a history of congenital heart defects.

Mitral atresia is a complex congenital heart defect characterized by the absence or underdevelopment of the mitral valve. It presents with significant symptoms shortly after birth and requires a combination of surgical and medical management. While the condition poses serious challenges, advances in treatment have improved outcomes, allowing many patients to lead fulfilling lives. Ongoing research aims to better understand its causes and improve therapeutic options.

If you or a loved one has been diagnosed with mitral atresia, it's important to understand that this is a rare heart condition present from birth. It affects how blood flows through the heart, leading to symptoms like difficulty breathing and bluish skin. Treatment usually involves surgery to help the heart work better, and ongoing care is necessary to monitor heart health. With modern medical advances, many people with mitral atresia can live active lives. Always follow your healthcare provider's advice and attend regular check-ups to ensure the best possible outcomes.

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