Congenital heart disease By Dr Saima Ali Professor of pediatrics

What is the most striking clinical finding in this child ?

Learning objectives

By the end of this lecture, final year student should be able to • Classify different types congenital heart disease. • Discuss the pathophysiology of congenital heart

disease. •  Interpret the CXR and ECG of acynotic heart

disease. • Manage a child with acyanotic heart disease and

refer appropriately whenever needed.

Lets

Fetal circulation

•  Three cardiovascular structures unique to the fetus are important for maintaining this parallel circulation:

• the ductus venosus, •  foramen ovale, and • ductus arteriosus.

prevalence

v Congenital heart disease occurs in 0.5–0.8% of live births.

v When two 1st-degree relatives have congenital heart disease, the risk for a subsequent child may reach 20–30%.

classification

CHD is divided into • Acyanotic heart disease (L-R shunt lesion)

•  cyanotic heart disease (R-L shunt lesion)

Acyanotic heart disease L-R shunt lesions: •  Atrial Septal Defect •  ventricular Septal Defect •  Patent ductus arteriosus

Obstructive Lesions •  Pulmonary stenosis •  Aortic stenosis •  Coarctation of aorta

Regurgitant Lesions •  Pulmonary regurgitation •  Aortic regurgitation •  Mitral valve prolapse

Ventricular Septal Defect •  Is the most common congenital heart disease.

VSD may be •  supracristal •  perimembranous or •  muscular • 

Pathophysiology

CLINICAL MANIFESTATIONS

Clinical finding depends upon ü Size of the defect

ü pulmonary blood flow and pressure

CLINICAL MANIFESTATIONS

•  dyspnoea, •  feeding difficulties, •  poor growth, •  profuse perspiration, •  recurrent pulmonary infections, and •  cardiac failure in early infancy

Precordium exam

ü palpable parasternal lift, ü a laterally displaced apical impulse , ü a systolic thrill. ü The holosystolic murmur of grade 4 or above ü  increased intensity of pulmonic component of

the 2nd heart sound ü mid-diastolic, low-pitched rumble at the apex

When would be the 2nd heart sound loud on auscultation of precordium?

DIAGNOSIS. ü CXR ü ECG ü ECHO

Interpretation of CXR?

Interpretation of CXR?

TREATMENT

• WHICH TYPE OF VSD IS MOST LIKELY TO CLOSE?

•  FOR HOW LONG SHOULD WE WAIT FOR VSD TO CLOSE SPONTANOUSLY?

TREATMENT

• CAN LARGE VSD CLOSE SPONTANOUSLY?

TREATMENT OF SMALL VSD

•  an isolated, small, hemodynamically

insignificant VSD is not an indication for surgery

•  Prophylactic antibiotics,

TREATMENT OF large VSD

Medical management has two aims: •  to control heart failure and

•  to prevent the development of pulmonary vascular disease

Indications for surgery •  patients at any age with large defects in whom clinical

symptoms and failure to thrive cannot be controlled medically;

•  infants between 6 and 12 mo of age with large defects associated with pulmonary hypertension, even if the symptoms are controlled by medication;

•  patients older than 24 mo with a Qp : Qs ratio greater than 2 : 1.

•  Patients with supracristal VSD of any size

Atrial septal defect

ASD

•  sinus venosus defect: high in septum • Ostium secundum defect: midseptum • Ostium primum defect: low in septum

CLINICAL MANIFESTATIONS

•  dyspnea, •  easy fatigability, •  palpitations, •  sustained atrial arrhythmia •  heart failure.

CLINICAL MANIFESTATIONS

• A right ventricular systolic lift •  A loud 1st heart. • Wide fixed splitting of the 2nd heart sound • A short, rumbling mid-diastolic murmur

produced by the increased volume of blood flow across the tricuspid valve

• Ejection systolic murmur at the upper left sternal border

CXR ECG ECHO

complications

•  pulmonary hypertension, •  atrial dysrhythmias, •  tricuspid or mitral insufficiency, and •  heart failure •  infective endocarditis

treatment

• ASDs detected in term infants may close spontaneously

•  Surgical or transcatheter device closure is advised for all symptomatic patients and also for asymptomatic patients with a Qp : Qs ratio of at least 2 : 1.

•  The timing for elective closure is after the 1st yr and before entry into school

Patent ductus arterious

Patent ductus arterious

•  Functional closure of the ductus normally occurs soon after birth, but if the ductus remains patent , aortic blood is shunted into the pulmonary artery.

•  PDA persisting beyond the 1st few weeks of life in a term infant rarely closes spontaneously

PATHOPHYSIOLOGY

• As a result of the higher aortic pressure, blood shunts left to right through the ductus, from the aorta to the pulmonary artery

•  In extreme case, 70% of the left ventricular output may be shunted through the ductus to the pulmonary circulation

•  Displaced and heaving apex beat •  Machinery or rolling thunder murmur at left

upper sternal border.

diagnosis

• CXR • ECG: LVH

treatment

Irrespective of age, patients with PDA require surgical or catheter closure