Overview of Pulmonary Incompetence
Pulmonary incompetence is a hemodynamic disorder in which blood flows from the pulmonary artery through the pulmonary valve into the right ventricle during right ventricular diastole as a result of organic or functional damage to the pulmonary valve. Pulmonary incompetence often occurs in association with other cardiovascular diseases, and is especially likely to occur in people with pulmonary hypertension. Congenital pulmonary incompetence alone is rare.
Etiology
The most common etiology is root dilatation of the pulmonary trunk secondary to pulmonary hypertension, causing enlargement of the annulus, as seen in conditions such as rheumatic mitral valve disease and Eisenmenger’s syndrome. Less common etiologies include pulmonary artery dilatation in idiopathic and Marfan syndrome.
Primary damage to the pulmonary valve is rare and may occur in infective endocarditis, pulmonary stenosis or after surgery for tetralogy of Fallot, carcinoid syndrome, and rheumatic heart disease.
Symptoms
Early clinical symptoms of pulmonary valve insufficiency are palpitations, shortness of breath, susceptibility to respiratory infections, edema in heart failure, paroxysmal dyspnea, hepatomegaly, dysuria, and arrhythmia.
Examination
1. Physical signs
(1) Heart sounds In pulmonary hypertension, the second heart sound pulmonary valve component is enhanced. Right ventricular beat volume increases, ejection time is prolonged, and the second heart sound is widely split. The increased right heart beat volume causes sudden dilatation of the enlarged pulmonary arteries producing systolic ejection sounds, which are most pronounced in the 2nd intercostal space at the left edge of the sternum. The third and fourth heart sounds are often present in the fourth intercostal space at the left sternal border and are enhanced during inspiration.
(2) Heart murmurs Secondary to pulmonary hypertension, an early diastolic sighing, high-pitched, decreasing murmur that begins immediately after the second heart sound in the 2nd-4th intercostal spaces of the left sternal border and increases with inspiration is called the Graham Steell murmur. A systolic jet murmur follows the second intercostal jet at the left border of the sternum due to pulmonary artery dilatation and increased right heart beat volume.
2. Electrocardiogram
Right ventricular hypertrophy may be seen in pulmonary hypertension.
3. X-ray examination
X-ray examination mainly shows enlargement of the right ventricle and pulmonary trunk.
4. Echocardiography
Doppler examination is extremely sensitive in confirming the diagnosis of pulmonary valve insufficiency and can semi-quantify the degree of regurgitation. Two-dimensional echocardiography is helpful in identifying the cause of the disease.
Diagnosis
The diagnosis is easy to make based on the characteristics of heart sound changes on auscultation, combined with imaging tests such as echocardiography.
Treatment
Simple pulmonary artery insufficiency usually does not need to be treated, only need to prevent the complication of bacterial endocarditis. Treatment of the primary disease causing pulmonary hypertension is the main focus, and when severe pulmonary regurgitation leads to intractable right ventricular failure, the valve should be treated surgically. Currently, pulmonary valve replacement is the mainstay of treatment for pulmonary regurgitation.