Atrioventricular Septal Defects (AVSD)
Atrioventricular septal defects (AVSD), also known as atrioventricular canal defects, are congenital heart conditions characterized by the improper formation of the heart's septum, which separates the upper and lower chambers. This defect can lead to significant cardiovascular complications if not addressed promptly.
Types of Atrioventricular Septal Defects
Atrioventricular septal defects are classified into three main categories:
Complete AV Septal Defect
In a complete AV septal defect, there is a significant deficiency in the heart's septation, resulting in large openings between both the atria and ventricles. This condition often features a common atrioventricular valve that does not separate into distinct right and left valves, leading to substantial blood flow from the left to the right side of the heart (left-to-right shunt). This shunting increases pulmonary blood flow and can cause heart failure symptoms early in life, typically within the first few weeks after birth.
Partial AV Septal Defect
A partial AV septal defect involves a smaller atrial septal defect (ASD) and a well-formed ventricular septum. In this case, there are distinct right and left atrioventricular valves, but the left-sided valve may exhibit leakage due to an incomplete formation. Symptoms may not be evident during infancy but can develop during adolescence or adulthood as heart function declines.
Transitional AV Septal Defect
Transitional AV septal defects exhibit characteristics of both complete and partial forms. They involve an ostium primum ASD and a small or moderate-sized ventricular septal defect (VSD). Symptoms can vary based on the size of the VSD and may manifest similarly to those of partial defects.
Symptoms of Atrioventricular Septal Defects
The symptoms associated with AVSD can vary significantly depending on the type and severity of the defect:
- Complete AV Septal Defect: Symptoms often appear within 4 to 6 weeks of birth and may include rapid breathing, difficulty feeding, poor weight gain, sweating, and fatigue.
- Partial AV Septal Defect: Many infants remain asymptomatic; however, those with significant mitral regurgitation may show signs of heart failure as they grow older.
- Transitional AV Septal Defect: Symptoms depend on the size of the VSD; mild cases may not present symptoms until later in life.
Diagnosis and Treatment
Diagnosis of atrioventricular septal defects typically involves echocardiography to visualize the heart's structure. In some cases, additional imaging or diagnostic tests may be necessary.
Treatment Options:
- Surgical Repair: Most patients require surgical intervention to close the septal defects and restore proper valve function. The timing of surgery often occurs between 2 to 4 months of age for complete defects or later for partial forms based on symptom severity.
- Postoperative Care: After surgery, many patients experience significant improvements in their quality of life and can live into adulthood with proper follow-up care.
Atrioventricular septal defects are serious congenital heart conditions that necessitate early diagnosis and intervention. With advancements in pediatric cardiology and surgical techniques, children with AVSD can achieve favorable outcomes, allowing them to lead healthy lives. At Sheikh Shakhbout Medical City (SSMC), specialized care is available for managing these complex conditions effectively.
