Valvular and Congenital Heart Disorders

Valvular Heart Disease

• Aortic stenosis: the aortic valve is not completely open, causing difficulty in pumping blood to the aorta during systole.
• Aortic regurgitation: an incompetent/leaky aortic valve allows blood to leak back to the left ventricle during diastole.
• Mitral stenosis: the mitral valve is not completely open, reducing blood flow through the mitral valve during diastole.
• Mitral regurgitation: an incompetent mitral valve allows backflow of blood from the left ventricle to the left atrium during systole.

Cardiac Valves

• Mitral valve: separates the left atrium and left ventricle.
• Aortic valve: separates the left ventricle and aorta.
• Pulmonary valve: separates the right ventricle and pulmonary artery.
• Tricuspid valve: separates the right atrium and right ventricle.

Systole vs Diastole

• Systole: the heart muscle contracts, pumping blood out of the heart.
• Diastole: the heart muscle relaxes, allowing blood to flow into the heart.
• Mitral and tricuspid valves are closed during systole.
• Aortic and pulmonic valves are closed during diastole.

Valvular Abnormalities

• Stenosis: narrowing of the valve, reducing blood flow.
• Regurgitation: backflow of blood through the valve.

Murmurs

• Murmurs are prolonged sounds during systole or diastole due to turbulent flow across abnormally structured valves.
• Systolic murmurs are associated with aortic stenosis and mitral regurgitation.
• Diastolic murmurs are associated with aortic regurgitation and mitral stenosis.

Auscultation

• Auscultation is the process of listening to heart sounds using a stethoscope.
• Aortic stenosis is best auscultated at the right 2nd intercostal space.
• Mitral regurgitation is best auscultated at the 5th intercostal space left midclavicular line.
• Aortic regurgitation is best auscultated at the 2nd intercostal space close to the sternal border.
• Mitral stenosis is best auscultated at the 5th intercostal space left midclavicular line.

Rheumatic Heart Disease

• Rheumatic heart disease is a permanent valvular abnormality that evolves over years following one or several episodes of acute rheumatic fever.
• Acute rheumatic fever occurs 2-3 weeks following strep pharyngitis caused by rheumatogenic types of Streptococcus Group A β-hemolyticus.
• Rheumatic heart disease affects all layers of the heart, including valves, joints, skin, and brain.

Pathologic Changes

• Aortic stenosis leads to increased resistance to flow, left ventricular pressure afterload, and left ventricular hypertrophy.
• Mitral regurgitation leads to increased left atrial volume, backflow of blood to the pulmonary circulation, and pulmonary vascular congestion.
• Aortic regurgitation leads to increased left ventricular end-diastolic volume, left ventricular dilation, and pulmonary vascular congestion.
• Mitral stenosis leads to left atrial enlargement, atrial fibrillation, and pulmonary vascular congestion.

Presentation and Diagnosis

• Aortic stenosis may present with systolic murmurs, angina, syncope, and dyspnea.
• Mitral regurgitation may present with systolic murmurs, dyspnea, palpitations, and S3 sound.
• Aortic regurgitation may present with diastolic murmurs, dyspnea, wide pulse pressure, and bounding pulses.
• Mitral stenosis may present with diastolic murmurs, dyspnea, and atrial fibrillation.
• Diagnosis is made using echocardiography (ECHO) and may involve the detection of valvular abnormalities, left ventricular hypertrophy, and left atrial enlargement.

Treatment

• Aortic stenosis is treated with aortic valve replacement.
• Mitral regurgitation is treated with mitral valve replacement or anticoagulation if atrial fibrillation is present.
• Aortic regurgitation is treated with aortic valve replacement.
• Mitral stenosis is treated with mitral valve replacement or anticoagulation if atrial fibrillation is present.