Physiology Congenital Heart Disease Bill Cayley MD MDiv University of Wisconsin

Learning Objectives Participants will be able to – Describe common congenital cardiac abnormalities – Discuss the clinical implications of common congenital cardiac abnormalities – Describe appropriate medical and surgical management of patients with common congenital cardiac abnormalities

Congenital heart disorders Abnormalities present from birth Range – – Asymptomatic, discovered late in life – Severe, threaten life of newborn Some form affects 1 of every 1000 newborns

Overview Anatomy Shunting – Ventricular overload? – Ventricular hypertrophy? – Cyanosis? – Pulmonary hypertention? Medical management Surgical management – Endocarditis?

Congenital heart disorders Atrial septal defects Ventricular septal defects Atrioventricular canal Tetralogy of Fallot Transposition of the great arteries Tricuspid atresia Ebstein’s anomaly Pulmonary atresia Hypoplastic left heart syndrome Truncus arteriosus Double-outlet right ventricle Total anomalous pulmonary venous connection

Epidemiology: Prevalence  In the presence of neonatal surgical capability, approximately 85% of patients survive to adulthood

Epidemiology: Prevalence Population Prevalence: 1-5% Relative Prevalence: Ventricular Septal Defect42-45% Atrial Septal Defect15-20% Tetralogy of Fallot12-26% Patent Ductus Arteriosus6% Transposition of Great Arteries2% Sources: Int J Cardiol 113:440-1, J Natl Med Assoc.99:665-9, Niger Postgrad Med J. 15:82-8

Epidemiology: Age at diagnosis Kenyatta National Hospital 2000 – 2004 – 214 referrals to pediatric cardiology – Mean ages: CHD first suspected: 9-19 months Referral to pediatric cardiology: 17 months Echocardiographic confirmation: 19 months

Normal cardiac function

Cardiac Exam

With patient supine, examine the 4 percordial areas with the diaphragm: - Aortic region- Pulmonic region - Tricuspid region - Mitral region Additional maneuvers: – Patient to turns to left side, listen with the bell of the stethoscope at the apex for mitral stenosis (low pitched diastolic murmur). – Patient sits upright, re-examine the 4 percordial regions, again with the diaphragm of the stethoscope. – Patient leans forward, exhales, and holds breath. Listen with the diaphragm between the second and third intercostal spaces at the right sternal (aortic) and left sternal (pulmonic) areas for aortic regurgitation.

Atrial Septal Defects (ASD)

LV → RV shunt – RV overload & HF – Dysrythmias – Pulmonary infections – Pulmonary htn

Atrial Septal Defects (ASD) Symptoms: SOB, palpitations Exam: precordial lift, split S2 CXR: Cardiomegally Mgmt – Appropriate mgmt of atrial dysrhythmias Cardioversion? Anticoagulation? – Closure of large shunts – Endocarditis rare, prophylaxis not indicated in isolated ASD – Activity restriction not needed for small defects

Ventricular septal defects (VSD)

Opening between ventricles, 4 types – 1: Outflow of RV, rare spontaneous closure. – 2: Defect in membranous septum, minimal shunt. – 3: Lower right ventricle common in Down Sx. – 4: Centrally, apically, or margin of the septum and RV free wall

Ventricular septal defects (VSD) Possible presentations – An asymptomatic patient with a systolic murmur – Fever or bacteremia due to endocarditis – A new diastolic murmur due to aortic valve prolapse – Cyanosis and exercise intolerance Defect size (in relation to aortic annulus) – < 25%: small shunts, no volume overload, no pulmonary htn – 25% - 75%: moderate shunting & LV overload, and mild pulmonary htn – > 75%: marked shunting, volume overload, and pulmonary htn.

Ventricular septal defects (VSD) Typical clinical features – SEM at left lower sternal border Clinical issues – Women with small VSDs and no pulmonary htn have no increased cardiovascular risk for pregnancy. – Women with pulmonary htn should NOT attempt pregnancy – No activity restrictions are needed for small VSDs with normal ventricular function – If pulmonary htn is present, activity is usually self- restricted

“Tetralogy of Fallot” (TOF) Ventricular septal defect (VSD) Pulmonary artery obstruction “Overriding aorta” – Aorta lies over the ventricular septal defect Right ventricular hypertrophy (RVH)

“Tetralogy of Fallot” (TOF)

Unoperated patients rare w/ surgical access Unoperated patients may have – Mild cyanosis – Severe cyanosis and continuous murmur

Other conditions Transposition of the great arteries – Reversal of the aorta and the pulmonary artery Tricuspid atresia – Inadequate development of the tricuspid valve Ebstein’s anomaly – Tricuspid valve has only one or two leaflets Pulmonary atresia – Inadequate development of the pulmonary valve Hypoplastic left heart syndrome – Inadequate development of the left ventricle Truncus arteriosus – Large VSD with a outflow to the pulmonary artery and the aorta

Social considerations Few studies Depression and anxiety more common? – 20 % general population – > 30% among adult CHD population May affect – Exercise and sports – Reproduction

Infective endocarditis (IE) 1.CHD patients must be informed of their potential risk for IE 2.When patients with CHD present with an unexplained febrile illness and potential IE, blood cultures should be drawn before antibiotic treatment is initiated to avoid delay in diagnosis due to "culture-negative" IE. 3.Transthoracic echocardiography (TTE) should be performed when the diagnosis of native-valve IE is suspected. 4.Transesophageal echocardiography (TEE) is indicated if TTE windows are inadequate or equivocal. 5.CHD patients with evidence of IE should have early consultation with a surgeon with experience in CHD

IE and antibiotic prophylaxis Antibiotic prophylaxis before dental procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa is reasonable in patients with CHD with the highest risk for adverse outcome from IE. It is reasonable to consider antibiotic prophylaxis against IE before vaginal delivery at the time of membrane rupture in select patients with the highest risk of adverse outcomes. Prophylaxis against IE is not recommended for nondental procedures (such as esophagogastroduodenoscopy or colonoscopy) in the absence of active infection.

Non-cardiac surgery High risk conditions – Pulmonary hypertension – Cyanotic congenital heart disease – NYHA class III or IV Heart Failure – Severe systolic ventricular dysfunction (EF < 35%) – Severe left-sided heart obstructive lesions Moderate risk – Prosthetic valve or conduit – Intracardiac shunt – Moderate left-sided heart obstruction – Moderate systolic ventricular dysfunction

Non-cardiac surgery Evaluation – History and exam Functional capacity? Signs of heart failure? Cyanosis? – Testing CXR ECG Hemogram and coagulation studies Echocardiogram?

Overview - again Anatomy Shunting – Ventricular overload? – Ventricular hypertrophy? – Cyanosis? – Pulmonary hypertension? Medical management Surgical management – Endocarditis?

Resource ACC/AHA 2008 Guidelines for the Management of Adults with Congenital Heart Disease. Circulation Dec 2;118(23):e PMID: (

THANKS!