Straddling or overriding tricuspid valve is a congenital heart defect in which the tricuspid valve is abnormally positioned in the heart. Instead of being located between the right atrium and right ventricle, the valve is located between the right atrium and left ventricle. This causes the right ventricle to be partially or completely blocked, resulting in a decrease in blood flow to the lungs.

Symptoms of straddling or overriding tricuspid valve include shortness of breath, fatigue, chest pain, palpitations, and swelling of the legs and abdomen. Other symptoms may include a bluish tint to the skin, dizziness, and fainting.

1. Congenital heart defects: Straddling or overriding tricuspid valve can be caused by a congenital heart defect, such as a ventricular septal defect (VSD) or an atrioventricular septal defect (AVSD).

2. Cardiomyopathy: Cardiomyopathy, a condition in which the heart muscle becomes weakened or damaged, can cause the tricuspid valve to become displaced.

3. Hypertrophic cardiomyopathy: Hypertrophic cardiomyopathy is a condition in which the heart muscle becomes thickened, which can cause the tricuspid valve to become displaced.

4. Pulmonary hypertension: Pulmonary hypertension is a condition in which the pressure in the pulmonary arteries is higher than normal, which can cause the tricuspid valve

1. Medication: Medications such as diuretics, ACE inhibitors, and beta-blockers may be prescribed to reduce the strain on the heart and improve symptoms.

2. Surgery: Surgery may be recommended to repair or replace the tricuspid valve. This may involve open-heart surgery or a minimally invasive procedure.

3. Transcatheter Tricuspid Valve Repair: This procedure involves inserting a catheter into the heart to repair the tricuspid valve.

4. Transcatheter Tricuspid Valve Replacement: This procedure involves inserting a catheter into the heart to replace the tricuspid valve with a prosthetic valve.

1. Congenital heart defects
2. Cardiomyopathy
3. Hypertension
4. Valvular heart disease
5. Infective endocarditis
6. Rheumatic heart disease
7. Atrial fibrillation
8. Pulmonary hypertension
9. Cardiac surgery
10. Pericardial effusion

At this time, there is no cure for straddling or overriding tricuspid valve. Treatment typically involves medications to reduce the symptoms and improve the function of the heart. These medications may include diuretics, ACE inhibitors, beta-blockers, and anticoagulants. In some cases, surgery may be necessary to repair or replace the tricuspid valve.