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ADULT CONGENITAL HEART DISEASE- COMMON CONDITIONS. October 13, 2009. Case #1.
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ADULT CONGENITAL HEART DISEASE- COMMON CONDITIONS October 13, 2009
Case #1 • 47 year old male pilot was evaluated by his employer’s NP and noted to have an abnormal ECG. Echocardiogram was ordered and showed a bicuspid aortic valve with mild AI. Employer suspended his work pending your evaluation. The patient, his attorney, and his insurance company have requested a statement from you as to the cause, possible complications, and treatment options associated with a congenital malformation of the aortic valve.
Bicuspid Aortic Valve: Epidemiology • Most common congenital heart condition (1-2%) • 4:1 M:F predominance • Limited evidence of autosomal dominant inheritance with varying penetrance • Usually diagnosed incidentally but represents a syndrome of abnormal development
Bicuspid Aortic Valve: Pathophysiology • Syndrome of abnormal development (think “bicuspid aortopathy”) • Genetic vs. environmental cause is controversial • Accelerated degeneration of aortic media leads to increased risk of dissection and aneurysm formation • Comorbid conditions: coarctation, PDA, R sided aortic arch • IT’S NOT JUST THE VALVE
Bicuspid Aortic Valve- Diagnosis • Echocardiogram “Fish mouth” appearance • MRI can demonstrate fusion and is useful to screen for aortic dilation (50% of cases) and other associated abnormalities
Bicuspid aortic valve- prognosis • Majority of patients will require surgical therapy, most commonly for aortic stenosis • Early aortic regurgitation suggests a more severe disease process and is marker of risk for aortic complications • 1/3 of patients develop severe comorbidities- CHF, aortic dissection, aortic aneurysm • Significant variation in disease process among individual patients
Bicuspid Aortic Valve- Management • Serial CT follow-up necessary once root enlargement is noted • Associated with R sided aortic arch and other congenital heart defects - should be managed on individual basis • Early referral to CT surgery for discussion of surgical options once when aortic root > 40 mm or for asymptomatic severe AI or AS • Screening of family members can probably be limited to physical exam • Endocarditis prophylaxis is recommended for invasive dental procedures
Case# 2 • 57 M presented to the ED from his primary care doctor’s office with CP and palpitations. • He was in usual state of health until 5 days prior to admission. That day he was mowing his lawn when he developed chest “pressure”, palpitations, and leg weakness. He felt “winded” and had a syncopal episode for several seconds. There was no head trauma or confusion. • Since then he has had constant substernal chest pressure and palpitations on minimal exertion.
PHYSICAL EXAMINATION • T 98.4, BP 101/69, P76, RR 20, POx 95% • 6’1”, 80 kg, BMI 24.75 • G: alert, appropriate • H: NC/AT • N: JVP 7cm, no bruit • C: CTA • H: RRR, no murmurs, fixed split S2 • A: +BS, soft, NTND • E: no c/c/e
CARDIAC CATHDIAGNOSTIC UTILITY IN ATRIAL SEPTAL DEFECTS • Evaluate for coronary artery disease in patients who are anticipated to undergo surgery • Confirm presence and level of shunt • Measure pulmonary vascular resistance • Estimate shunt ratio (Qp/Qs) – The Gold Standard • Assess for other defects (i.e. anomalous venous communications)
ATRIAL SEPTAL DEFECTSNATURAL HISTORY DECADES OF LIFE 1st 2nd 3rd 4th 7th 5th 6th Symtoms may appear in the presence of a large ASD. Periodic screening is recommended at this point. Patients are typically asymptomatic, unless another associated defect is present. Atrial arrhythmias Paradoxical embolism Right ventricular failure Tricuspid and mitral regurgitation Pulmonary Hypertension Eisenmenger’s syndrome Premature sudden death Rigby ML: Atrial Septal Defect. In Gatzoulis MA, et al. (eds): Diagnosis and Management of Adult Congenital Heart Disease, Edinburgh, Churchill Livingstone, 2003, p. 163-170. Weigers SE, St John Sutton MG. http://www.uptodate.com version 12.1, 2003.
LSPV 97% High SVC 63% PA 87% Low SVC 94% RA Mid 87% sinus venosus ASD RV 84% High IVC 62% FA 95%
CARDIAC CATH 5/24/04CALCULATION OF SHUNT RATIO Qp/Qs Therefore… Qp/Qs = {95 – [3(63) + 62]}/(97 – 87) Qp/Qs = 3.2/1.0 O2 consumption (ml/min) 10 x [arterial – mixed venous O2 difference] (ml202/dl blood ) Systemic Flow (L/min) = O2 consumption (ml/min) 10 x [pulmonary vein – pulmonary artery O2 difference ] Pulmonary Flow (L/min) = Where the O2 content = 1.36 (mL O2/g hemoglobin) x Hgb (g/dl) x SO2 Qp SAO2 – MVO2 Where MVO2 = (3SVCO2 + IVCO2)/4 This simplifies to…. = Qs PVO2 – PAO2 4
ATRIAL SEPTAL DEFECTSTYPES RSPV 20% 10% 70% rare Perloff JK. Clinical Recognition of Congenital Heart Disease, 5th ed. Philadelphia, WB Saunders, 2003.
ATRIAL SEPTAL DEFECTSTYPES OSTIUM SECUNDUM - defect in the fossa ovalis due to: • Shortening of the valve of the foramen ovale • Excessive resorption of the the septum primum • Deficient growth of the septum secundum OSTIUM PRIMUM – failure of the primum septum to fuse with the endocardial cushions SINUS VENOSUS – abnormality in the insertion of the superior vena cava CORONARY SINUS - deficiency in the wall between the coronary sinus and the left atrium
ATRIAL SEPTAL DEFECTSNATURAL HISTORY SYSTEMIC-TO-PULMONARY CIRCULATION CONNECTION | LEFT-TO-RIGHT SHUNTING OF BLOOD | INCREASED PULMONARY BLOOD FLOW | IRREVERSIBLE PULMONARY VASCULAR INJURY (variable) | INCREASED PULMONARY VASCULAR RESISTANCE | Eisenmenger’s Syndrome (relatively uncommon) RIGHT-TO-LEFT SHUNTING OF BLOOD | HYPOXIA AND ERYTHROCYTOSIS Adapted from Vongpatanasin W, et al. Ann Intern Med. 1998; 128: 745.
ATRIAL SEPTAL DEFECTSPOSSIBLE BENEFITS OF CLOSURE • Improved survival compared to medical therapy • Improved functional class • Improved exercise tolerance • Reduction in the risk of heart failure • Reduction in the risk of pulmonary hypertension Rigby ML: Atrial Septal Defect. In Gatzoulis MA, et al. (eds): Diagnosis and Management of Adult Congenital Heart Disease, Edinburgh, Churchill Livingstone, 2003, p. 163-170. Weigers SE, St John Sutton MG. http://www.uptodate.com version 12.1, 2003.
ATRIAL SEPTAL DEFECTSINDICATIONS FOR CLOSURE • PATHOLOGICAL PROCESSES • Right ventricular dilatation • PASP ≤50% of aortic pressure • Symptoms with a demonstrated left-to-right shunt 2. HEMODYNAMICALLY SIGNIFICANT SHUNT • Pulmonary-to-systolic flow ratio (Qp/Qs) ≥ 2:1* * NOTE: • American Heart Association advocates Qp/Qs ≥1.5:1, but excludes those > age 21 • Canadian Cardiac Society advocates Qp/Qs >2:1, or >1.5:1 in the presence of reversible pulmonary hypertension Rigby ML: Atrial Septal Defect. In Gatzoulis MA, et al. (eds): Diagnosis and Management of Adult Congenital Heart Disease, Edinburgh, Churchill Livingstone, 2003, p. 163-170. Weigers SE, St John Sutton MG. http://www.uptodate.com version 12.1, 2003.
ATRIAL SEPTAL DEFECTSCONTRAINDICATIONS FOR CLOSURE • PVR >1200 dyne-sec-cm -5 • Eisenmenger’s syndrome • ASD with a diameter <8mm without symptoms* * Some feel all ASDs should be closed Rigby ML: Atrial Septal Defect. In Gatzoulis MA, et al. (eds): Diagnosis and Management of Adult Congenital Heart Disease, Edinburgh, Churchill Livingstone, 2003, p. 163-170. Weigers SE, St John Sutton MG. http://www.uptodate.com version 12.1, 2003.
LATE DEATHS PER DEATH CERTIFICATES (n = 26) 5 heart failure 3 congenital heart disease 2 valvular heart disease 1 myocardial infarction 2 unspecified cardiac disease 5 stroke 2 motor vehicle accident 3 carcinoma 2 sepsis 1 respiratory failure OVERALL 30-YEAR SURVIVAL 74% in ASD repaired patients 85% in age and sex matched controls ATRIAL SEPTAL DEFECTSNATURAL HISTORY – CAUSES OF DEATH Murphy JG, et al. NEJM. 1990; 323: 1645-50.
A COMPARISON OF SURGICAL AND MEDICAL THERAPY FOR ATRIAL SEPTAL DEFECT IN ADULTS 10-year survival rate (medical) = 84% 10-year survival rate (surgical) = 95% P = 0.02 Konstantinides S, et al. NEJM. 1995; 333: 469-73.
ATRIAL SEPTAL DEFECT IN ADULTS: CARDIOPULMONARY EXERCISE CAPACITY BEFORE AND 4 MONTHS AND 10 YEARS AFTER DEFECT CLOSURE Helber U, et al. JACC. 1997; 29: 1345-50.
PERCUTANEOUS CLOSURE • Only approved for closure of secundum defects • Device selection must be equal to, or slightly larger than, the balloon stretched diameter of the defect (4-8mm > resting diameter). So, the device stents the defect. • Contraindicated in patients with <5mm to coronary sinus, AV valves, or right upper pulmonary vein. http://www.amplatzer.com/
PERCUTANEOUS CLOSUREAMPLATZER SEPTAL OCCLUDER smallest largest A: device size (=stretched ASD) 4mm 38mm B: LA disc diameter 16mm 54mm C: RA disk diameter 12mm 48mm http://www.amplatzer.com/
IMPROVEMENT IN EXERCISE CAPACITY IN ASYMPTOMATIC AND MILDLY SYMPTOMATIC ADULTS AFTER ATRIAL SEPTAL DEFECT PERCUTANEOUS CLOSURE Brochu MC, et al. Circulation. 2002; 106: 1821-26.
Case #3 57 year old PhD with migraine headaches presented to the ER with HA and R sided weakness. MRI eventually showed small foci possibly consistent with embolic events. Transthoracic echo bubble study was positve for intra-atrial communication. What is the next step?
Evolution of the PFO • Ideal R to L shunt • Allows mixing of oxygenated umbilical venous blood with fetal systemic circulation • One of three fetal shunts- PFO, PDA, and ductus venosus
Adult PFO: Epidemiology • 27% of the general population at autopsy (probe patent PFO) • 10-15% by echo • Atrial septal aneurysm with or without PFO seen in 2% • No specific demographic factors have been associated with PFO
PFO: Pathophysiology • The foramen ovale closes and the septum secundum becomes attached to the septum primum during the first or second year of life • Patent Foramen Ovale is seen in roughly 15% of adults and is almost always inconsequential • PFO increases in size throughout life (Mayo Clinic autopsy study- 3.4 mm in 1st decade, 5.6 mm in 10th decade) • Turbulent flow through the PFO may be a nidus for thrombus formation and/or platelet activation
Shunt Epidemiology • R to L shunt- more likely inpatients with RV volume or pressure overload ~60% • L to R shunt- more common in patients with diastolic dysfunction or LV failure~ 20% • No shunt- PFO with mildly positive bubble study and no color flow likely does not represent a signficant shunt (probe patent?)~ 20% • Anatomy of the septum secundum favors R to L shunting
Migraine Physiology and the Heart • Multifactorial, probably vasodilatory headache associated with “aura” of visual symptoms • May be partially due to circulating vasodilatory substances • Increased incidence of migraine among children with cyanotic heart disease, and among adults with a history of congential heart disease
Adult Congenital Heart Disease and Migraine • Increased incidence among patients with cyanotic heart disease compared to normal population (40-70% vs. 15-25%) • Complete resolution of symptoms in 40-50% of patients with cyanotic CHD following surgery, with improvement noted in 70-80% • Incidence of migraine in patients with PFO is thought to be 30-40% Congenit Heart Dis. 2008 Mar;3(2):124-7.
Starflex PFO Closure • 2 discs of synthetic mesh on carbon alloy frame • Only PFO device with a published randomized trial http://www.migraine-mist.org/could_starflex_help.asp
MIST Results • After excluding 2 outliers, there was a signficant 37% reduction in total migraine headaches in the treatment group • Intention-to-treat, and per-protocol analysis were both negative for the primary outcome • No definite evidence of benefit
Does PFO lead to stroke? • Epidemiologic evidence • Case reports • Does this suggest causality? • What features are associated with increased stroke risk?
Atrial Septal Aneurysm • Clearly associated with PFO • When present with PFO, associated with increased risk of CVA/TIA • PFO occlusion across ASA may decrease turbulence and therefore decrease the risk of clot formation • Increase excursion (>10 mm) has been associated with increased stroke risk* *Stroke 1993 Dec;24(12):1865-73.
Stroke and Atrial Septal Aneurysm OR for Stroke Neurology. 2000 Oct 24;55(8):1172-9.
Long term risk of PFO/ASA • On Aspirin, 4 year recurrence rate for PFO with ASA was 15.2% compared to 4.2% for patients with ASA alone • Other similar studies have failed to show an increased risk *Mas JL, Arquizan C, Lamy C, Zuber M, et al, for the Patent Foramen Ovale and Atrial Septal Aneurysm Study Group. Recurrent cerebrovascular events associated with patent foramen ovale, atrial septal aneurysm, or both. N Engl J Med. 2001; 345: 1740–1746.