Cardiac Disorders (Valvular, Congenital) PDF

VALVULAR AND CONGENITAL HEART DISORDERS Irina Benenson, DNP, FNP Valvular heart disease Aortic stenosis Aortic regurgitation Mitral stenosis Mitral regurgitation Cardiac valves Systole vs diastole Mitral v Aortic v Pul...

VALVULAR AND CONGENITAL HEART DISORDERS Irina Benenson, DNP, FNP Valvular heart disease Aortic stenosis Aortic regurgitation Mitral stenosis Mitral regurgitation Cardiac valves Systole vs diastole Mitral v Aortic v Pulmonary v Tricuspid v Cardiac valves during systole Mitral and tricuspid valves are closed (closure corresponds with S 1) Cardiac valves during diastole Aortic and pulmonic valves are closed (closure corresponds with S 2) Valvular abnormalities: stenosis versus regurgitation Murmur associated with valvular disorders Murmur may be initial and only presentation of valvular disorders Murmur – prolonged sound during systole or diastole due to turbulent flow across abnormally structured valves Systolic murmurs The aortic valve is not completely open → aortic stenosis The mitral valve is not completely closed → mitral regurgitation Auscultation of systolic murmurs (aortic) Aortic stenosis: Auscultated best at the right 2nd intercostal space (close to the sternal border) Auscultation of systolic murmurs (mitral) Mitral regurgitation: Auscultated best at the 5th intercostal space left midclavicular line (the apex of the heart) Diastolic murmurs The mitral valve is not completely open → mitral stenosis The aortic valve is not completely closed → aortic regurgitation Auscultation of diastolic murmurs Aortic regurgitation: 2nd intercostal space close to the sternal border Mitral stenosis: 5th intercostal space left midclavicular line Pulmonic and tricuspid diastolic murmurs are difficult to auscultate (diagnosed by ECHO) Case 1: What is the most likely valvular pathology? A 76 y/o male patient with a history of hypertension and ischemic heart disease presents for a routine exam. He has no symptoms. On physical exam: Harsh systolic murmur with crescendo-decrescendo pattern, radiates to the neck, heard best at the right 2nd intercostal space close to the sternal border. Case 2: What is the most likely valvular pathology? A 28 y/o female at the 3rd trimester of pregnancy reports dyspnea with minimal activity. On physical exam: Low-pitched diastolic murmur best heard at the apex of the heart (left 5th intercostal space). There are crackles on lung auscultation. Case 3: What is the most likely valvular pathology? A 76 y/o with a history of hypertension presents with dyspnea on exertion. On physical exam: bounding peripheral pulses, BP is 170/40 mmHg. There is a decrescendo diastolic murmur best heard at the right 2nd intercostal space close to the sternal border. Case 4: What is the most likely valvular pathology? A 28 y/o female patient presents for a routine visit. She has no complaints. On physical exam: systolic murmur at the apex, left 5th intercostal space midclavicular line, radiates to the axilla. Common valvular abnormalities Associated with systolic murmurs Aortic stenosis Mitral regurgitation Associated with diastolic murmurs Aortic regurgitation Mitral stenosis Aortic stenosis Aortic valve is stenotic → difficult to pump blood to the aorta during systole Normal aortic valve Stenotic aortic valve Causes of aortic stenosis Degenerative calcific stenosis (most common, > 90% cases) Congenital Leaflets are partially fused Rheumatic disease Endocarditis Staphylococcal or Streptococcal infection Bacteremia following dental, surgical procedures, contaminated needles IVD, skin or mucosa breakdown Degenerative calcific aortic stenosis Chronic mechanical stress (wear and tear of the leaflets) = micro-tears of the endocardial cells (+ damage is accelerated by diabetes, smoking, obesity, hypertension) → repair (fibrosis) → the thickness of the leaflets (remodeling) → deposition of calcium (calcification) Common in older adults (> 60 y/o) Bicuspid valve (a In younger individuals, degenerative calcific changes is congenital due to congenital bicuspid valve (more stress per defect) presents in 1.5% leaflet → more damage) of population. Calcified tri-cuspid aortic valve Calcified bi-capsid aortic valve Rheumatic aortic stenosis Rheumatic heart disease → valve inflammation (infiltration of neutrophils, macrophages + release of cytokines)→ valve repair (fibrosis)→ leaflets fuse together and become thicker (valve remodeling)  Rheumatic heart disease Rheumatic heart disease (RHD) is a permanent valvular abnormality that evolves over years following one or several episodes of Acute rheumatic fever (ARF) Acute rheumatic fever (ARF) occurs 2-3 weeks following strep pharyngitis caused by rheumatogenic types of Streptococcus Group A β-hemolyticus (Streptococcus pyogenes) ARF is common in children (5-15 years) ARF affects all layers of the heart including valves (aortic and mitral), joints (polyarthritis of large joints), skin (subcutaneous nodules), brain (chorea, involuntary rapid purposeless movements) Rheumatic joint disease and chorea resolve without long-term consequences. RHD with permanent valve damage may develop in a subset of patients Incidence of ARF in the US declines Mechanism of acute rheumatic fever Infiltration of the valve by inflammatory cells MOLECULAR MIMICRY (neutrophils/lymphocy tes/macrophages ) MYOSIN (at the base of the valve) Pathologic changes in aortic stenosis Aortic stenosis → ↑ resistance to flow & LV pressure afterload → LV hypertrophy (main compensatory mechanism) LV hypertrophy → ↓ diastolic filling (diastolic HF) → pulmonary vascular congestion → pulmonary edema and impaired oxygenation Pulmonary venous congestion → structural changes in the pulmonary vasculature (vasoconstriction, thickness of the vascular wall) → pulmonary HTN LV hypertrophy → ↑ oxygen demand → myocardial ischemia Severe aortic stenosis → ↓perfusion to vital organs (renal damage most common) Presentation of aortic stenosis Asymptomatic for many years (compensatory LV hypertrophy) The only presentation is a systolic murmur best heard at the right 2nd intercostal space at the sternal border (the narrow the stenosis the lauder the murmur) Sometimes murmur is accompanied by an "ejection click" (when the stenotic valve pops open) Late presentation: Angina Syncope Dyspnea Pulses “parvus and tardus” S4 sound Presentation of aortic stenosis (pulse parvus and tardus) S4 sound (late diastole) Trembling of the atria (when it contracts against stiff thick ventricle) Can be normal in older adults Can be heard in patients with HTN and diastolic left-ventricular HF Diagnosis and treatment of aortic stenosis Diagnosis by ECHO: Aortic valve stenosis Left ventricular hypertrophy Treatment: Aortic valve replacement (surgery) Mitral regurgitation Incompetent mitral valve → back flow of blood from the LV to the LA during systole → Causes of mitral regurgitation LV dilation (most common cause): Systolic HF→ LV dilation → mitral valve ring stretches → leaflets separate → mitral regurgitation Mitral valve prolapse (1-3% of population) Infective endocarditis (rare) Rheumatic heart disease (rare) Acute mitral regurgitation (s/p transmural infarction with rupture of papillary muscles)  Mitral valve prolapse NORMAL FUNCTION OF MITRAL CHORDAE PROLAPSE TINDINEAE DEGENERATION OF CHORDAE TENDINEA OR DAMAGE TO THE PAPILLARY MUSCLES → PERMITTING LEAFLETS FOLD INTO THE ATRIA DURING SYSTOLE → REGURGITATION Pathologic changes in mitral regurgitation Mitral regurgitation → ↑ LA volume → backflow blood to the pulmonary circulation → pulmonary vascular congestion /edema & impaired oxygenation Pulmonary vascular congestion → pulmonary HTN Mitral regurgitation → ↑ LA volume → LA stretched → atrial fibrillation → risk for stroke (20% of patients with A-fib and mitral regurgitation) ↑ LA volume → ↑ volume that enters the LV during next diastole → LV dilation → systolic HF Presentation of mitral regurgitation Asymptomatic for years (compensatory LV dilation) Systolic murmur best heard at the apex, 5 th intercostal space left midclavicular line Sometimes associated with "mid-systolic click" in mitral valve prolapse Late presentation: Dyspnea Palpitations (if atrial fibrillation) S3 sound (increased rapid filling of the LV during diastole) Acute mitral regurgitation presents with acute pulmonary edema Abnormal S3 sound (early diastole) Trembling of the ventricle (when it fills with a large volume of blood during early diastole) Indicates volume overload Can be heard in left ventricular HF (systolic and diastolic) Diagnosis and treatment of mitral regurgitation Diagnosis by ECHO: Mitral regurgitation Enlarged left atria, enlarged left ventricle (cardiomegaly) Treatment: Mitral valve replacement Anticoagulation (if atrial fibrillation) Mitral valve prolapse with minimal regurgitation doesn’t require treatment Aortic regurgitation Incompetent/leaky aortic valve → blood leaks back to the LV during diastole Causes of aortic regurgitation Dilation of the ascending aorta (aortic root): root dilates → leaflets separate Idiopathic (80%), commonly associated w/ HTN (mechanical pressure) Syphilis (rare) Marfan syndrome (rare) Bicuspid aortic valve (doesn’t close properly) Infective endocarditis (rare) Rheumatic heart disease (rare) Pathologic changes in aortic regurgitation Aortic regurgitation → double LV end-diastolic volume → dilation of the LV → LV systolic HF → backflow of blood to the pulmonary circulation → pulmonary vascular congestion/ edema/ impaired oxygenation → pulmonary HTN  Presentation of aortic regurgitation Asymptomatic for many years (compensatory LV dilation) Diastolic murmur heard best at the right 2 nd intercostal space Late presentation Dyspnea Wide pulse pressure (↑ systolic and ↓ diastolic blood pressure) Bounding pulses S3 sound (exaggerated early diastolic filling of the LV) Wide pulse pressure Aortic regurgitation diagnosis and treatment Diagnosis by ECHO: Dilated aorta Aortic regurgitation LV dilation (cardiomegaly), may be detected also on x-ray Treatment: Aortic valve replacement Cardiomegaly Mitral stenosis Mitral stenosis → ↓ blood flow through the mitral valve during diastole Causes of mitral stenosis Rheumatic heart disease (most common) Infective endocarditis (rare) "Fish mouth" of mitral stenosis Pathologic changes in mitral stenosis Mitral stenosis → left atrial enlargement → atrial fibrillation → stroke (30% of patients with A-fib and mitral stenosis) Mitral stenosis → backflow to the pulmonary circulation → pulmonary vascular congestion/edema/impaired oxygenation → pulmonary HTN Presentation of mitral stenosis Asymptomatic for years (compensatory LA dilation) Low-pitched diastolic murmur best heard at the 5 th intercostal space left mid-clavicular line It may be accompanied by an "opening snap" Symptoms develop 20 y. after a first episode of acute rheumatic fever (age 30) Dyspnea Palpitations (if atrial fibrillation) Difficulty swallowing Hoarseness Dysphagia and hoarseness Diagnosis and treatment of mitral stenosis Diagnosis by ECHO: Mitral stenosis Enlargement of the left atrium Treatment: Balloon valvuloplasty (catheter) Tricuspid and pulmonary valve disorders Less common than left-sided valvular diseases Congenital, infective (endocarditis in IVDU) Murmurs are barely audible (rarely diagnosed in an asymptomatic period) Symptoms of right-sided failure (peripheral edema, hepatosplenomegaly) Congenital heart disease Ventricular septal defect Atrial septal defect Patent ductus arteriosus Coarctation of aorta Tetralogy of Fallot Congenital heart disease epidemiology Congenital heart disease is the most common congenital anomaly, occurring in almost 1% of live births Among birth defects, congenital heart disease is the leading cause of infant mortality Causes congenital heart diseases Unknown cause (> 70% of cases) Maternal illness (rubella, diabetes) Advanced maternal age Teratogenic agents (lithium, isotretinoin, anticonvulsants, alcohol) Genetic abnormalities (Down syndrome) Types of congenital heart disease Acyanotic not significant hypoxemia, no central cyanosis Cyanotic severe hypoxemia, SPO2 < 85% leading to central cyanosis Acyanotic heart defects Left-to-right shunt Atrial septal defect Ventricular septal defect Patent ductus arteriosus Non-shunt defect Coarctation of aorta Aortic stenosis Ventricular septal defect (VSD) Most common defect 30-50% of defects close spontaneously during childhood VSD Pulmonary HTN Pathologic changes in large VSD Left-to-right shunt → ↑ backflow to the lungs → pulmonary congestion/edema → pulmonary HTN → ↑ pulmonary vascular resistance ↑ afterload of the right ventricle → ↓ RV stroke volume → RV failure → backflow of blood to the peripheral veins (peripheral edema, hepatomegaly) Presentation of VSD Small VSD is asymptomatic Large VSD: Dyspnea (pulmonary vascular congestion/edema) Poor weight gain (increased work of breathing) Developmental delay Hepatomegaly and peripheral edema (RV failure) No cyanosis Atrial septal defect (ASD) ASD – blood shunt from higher pressure LA to lower pressure RA and RV Fully oxygenated blood enters second time pulmonary circulation No hypoxemia Pathologic changes in large ASD Left-to-right shunt → ↑ backflow to the lungs → pulmonary congestion/edema → pulmonary HTN → ↑ pulmonary vascular resistance ↑ afterload of the right ventricle → ↓ RV stroke volume → RV failure → backflow of blood to the peripheral veins (peripheral edema, hepatomegaly) Presentation of ASD Small ASD asymptomatic Large ASD: Dyspnea Poor weight gain Developmental delay Hepatomegaly No cyanosis Patent ductus arteriosus (PDA) Ductus arteriosus connects pulmonary artery and aorta during fetal life Patency maintained by prostaglandins (synthesized by placenta) Usually closes at 1-5 days of age If remains patent after 1 week → patent ductus arteriosus PDA during fetal development (normal)  PDA after birth (congenital abnormality) Pulmonary HTN Increased afterload to RV RV failure Pathologic changes of PDA Left-to-right shunt through the PDA→ ↑ backflow to the lungs → pulmonary congestion/edema → pulmonary HTN → ↑ pulmonary vascular resistance ↑ afterload of the right ventricle → ↓ RV stroke volume → RV failure → backflow of blood to the peripheral veins (peripheral edema, hepatomegaly) Presentation of PDA Small/ partially obliterated PDA asymptomatic Completely open PDA: Dyspnea Poor weight gain Developmental delay Hepatomegaly No cyanosis Coarctation of aorta (CoA) Acyanotic heart defect No shunt Narrowing of the descending aorta (usually distal to brachiocephalic, common carotid, left subclavian artery) Pathological changes of CoA Pathologic changes and complications of CoA Narrowing of the aorta → ↑afterload left ventricle → LV hypertrophy backflow blood to the lungs → pulmonary vascular congestion/edema → pulmonary HTN ↓perfusion to the lower extremity and kidneys → renal failure ↑aortic pressure → aortic and cranial aneurism Presentation of CoA Dyspnea BP difference between arms and legs: BP arms > BP legs Weak and delayed pulses in lower extremities (femoral, popliteal, dorsalis pedis) Bounding pulses of the arms (radial, brachial) and carotids Pain with walking (in older children and adults) No cyanosis Acyanotic defects diagnosis and treatment Diagnosis: ECHO Treatment (if large shunt): Surgical correction of large defects Indomethacin for PDA (inhibits prostaglandin E2 → closure of the PDA) Cyanotic heart defects Right to left shunt (deoxygenated blood is shunted to the left side and then to the systemic circulation, reducing oxygen saturation): Tetralogy of Fallot Transposition of great vessels Tetralogy of Fallot Most common cyanotic defect (70%) Only < 10% of all congenital heart defects Combination of 4 defects TOF: PA stenosis TOF: RV hypertrophy TOF: VSD with right-to-left shunt TOF: overriding aorta Presentation of TOF Central cyanosis (lips) Clubbing fingers Failure to gain weight (hypoxemia) Developmental delay Cyanotic spells (“tet spells”), corrected by spontaneous squatting Polycythemia (hypoxemia → ↑EPO → stimulation of the bone marrow) Central cyanosis Clubbing Dick Ket (1902-1932). Self-portrait Diagnosis and treatment of TOF Diagnosis: ECHO Treatment: repair of VSD, repair of pulmonary artery stenosis  Congenital heart disease: Let’s match Right-to-left shunt ASD Left-to-right shunt VSD Central cyanosis Pulmonary hypertension Patent ductus arteriosus Cyanotic spells Tetralogy of Fallot Polycythemia Coarctation of aorta