Cardiology

Question 1

What is coarctation of the aorta?

Answer 1

congenital narrowing of descending thoracic aorta

usually noncyanotic

Question 2

Etiology/Pathophysiology of coarctation of aorta

Answer 2

î LV afterload with SNS activity & RAAS (renin-angiotensis aldosterone system) activation ⇒ HTN, LVH, CHF

70% allso have bicuspid aortic valve**

Question 3

Clinical Manifestations of coarctation of aorta

Answer 3

** Secondary HTN **

bilateral claudication, dyspnea on exertion, syncope

infants: failure to thrive, poor feedings, shock

Types:

• infantile: preductal*
  adult: postductal

Question 4

Physical Exam findings for coarcation of aorta

Answer 4

• Systolic murmur that radiates to the back/scapula/chest*
• î BP upper > lower extremities*
• delayed/weak femoral pulses* (decreased flow distal to obstruction in lower extremities)

Question 5

Diagnosis of coarcation of aorta

Answer 5

CXR: Rib notching*: increased collateral circulation via intercostal arteries;

“3 sign” narrowed aorta looks like the notches of the #3

ECG: LVH

** Angiogram: gold standard

Question 6

Management of coarctation of aorta

Answer 6

surgical correction

balloon angioplasty + stent

prostaglandin E₁ (PGE₁) – preoperatively (reduces symptoms, improves lower extremity blood flow)

Question 7

What is the most common cyanotic congenital heart disease?

Answer 7

Tetralogy of Fallot

Question 8

4 factors included in Tetralogy of Fallot

Answer 8

1. RV outflow obstruction (pulmonary artery stenosis)

2. RVH

3. VSD (large unrestrictive)

4. overriding aorta – between ventricles

Question 9

Clinical Manifestations of Tetralogy of Fallot

Answer 9

* Blue Baby Syndrome (cyanosis)

* older: exertional dyspnea…cyanosis worsens with age

* Tet spells paroysms of cyanosis – older children relieve spells by squatting

* Eisenmenger’s Syndrome: seen with PDA, VSD, TOP (_+_ASD)

Question 10

Physical Exam Findings of Tetralogy of Fallot

Answer 10

* Harsh holosystolic murmur @ left upper sternal border (sounds like pulmonary stenosis)

* Right ventricular heave

* digital clubbing

Question 11

Diagnosis of Tetralogy of Fallot

Answer 11

* CXR: Boot-shaped heart* (prominent R ventricle)

* ECG: right ventricular hypertrophy*

also right atrial enlargment

*Echo: GOLD STANDARD DIAGNOSIS

Question 12

Management of Tetralogy of Fallot

Answer 12

surgical repair performed in the first 4 - 12 months of life

PGE₁ infusion: prevents ductal closure in cyanotic patients prior to surgery

Question 13

What is a patent ductus arteriosus?

Answer 13

communication between descending thoracic aorta & pulmonary artery

left to right (noncyanotic)

Question 14

Pathophysiology of a patent ductus arteriosus

Answer 14

prematurity, perinatal stress & hypoxia delays closure, Rubella infection in the 1st trimester

continued Prostaglandin E₁ production promotes patency

Question 15

Clinical Manifestations of a patent ductus arteriosus

Answer 15

• mostly asymptomatic
• poor feeding, weight loss, lower repiratory tract infections, pulmonary congestion
• Eisenmenger’s Syndrome: pulmonary HTN ⇒ left to right shunt switches & becomes right to left shunt (cyanosis)

Question 16

Physical Exam Findings of a patent ductus arteriosus

Answer 16

Continous Machinery Murmur

loudest at pulmonic area

wide pulse pressure: bounding peripheral pulses* loud S2

Eisenmenger: normal hands (upper extremities) with cyanotic lower extremities (clubbed, blue toes)

Question 17

Diagnosis of PDA

Answer 17

CXR: normal or cardiomegaly

ECG: LVH, LAE

Echo: GOLD STANDARD

Question 18

Management of PDA

Answer 18

IV Indomethacin 1st line

surgical correction if indomethacin fails, best if done before 1 - 3 years of age

Question 19

What is Hypertrophic Cardiomyopathy?

Answer 19

inherited genetic disorder of inappropriate LV and/or RV hypertrophy (especially septal)

Question 20

Pathophysiology of Hypertrophic Cardiomyopathy

Answer 20

SUBAORTIC OUTFLOW OBSTRUCTION: narrowed LV outflow tract secondary to

1. hypertrophied septum +

2. systolic anterior motion (SAM) of the mitral valve & papillary muscle displacement

• î SAM seen with:*
• a. î contractility: (ex. Digoxin, beta agonist, exercise)*
• b. d_ecreased LV volume:_ (ex. decreased venous return, dehydration, valsalva maneuver)*

_DIASTOLIC DYSFUNCTION:_ stiff ventricular chamber ⇒ imparied ventricular relaxation/filling (because thickened walls lead to a smaller LV volume & decreased LV filling)

Question 21

Clinical Manifestations of Hypertrophic Cardiomyopathy

Answer 21

1. Dyspnea: most common initial complaint* (90%) Fatigue.
   * 2. Angina Pectoris: (chest pain) 75%. usually in the same setting of a normal angiogram*
   * 3. Syncope: includes presyncope and dizziness (due to inadequate CO on exertion)*
   * 4. Arrhythmias: Afib; VT/VF (palpitations, syncope, sudden cardiac death)*

5. Sudden cardiac death:** esp. in adolescent/preadolescent children **(esp. during times of extreme exertion).** Usually due to **ventricular fibrillation

Question 22

Physical Exam of a patient with Hypertrophic Cardiomyopathy

Answer 22

1. _Harsh systolic crescendo-decrescendo murmur:*_ heard best @ LLSB (sounds similar to atrial stenosis)
   * – handgrip maneuver (increases afterload by constricting arterioles and increasing peripheral resistance) decreases murmur intensity; increased venous return (squatting, lying suping) decreases intensity because î LV volume preserves outflow (î fluid pushes septum out the way & decreases SAM of mitral valve)*
   * – î murmur intensity with decreased venous return* (ex: Valsalva & standing)*
   * – usually no carotid radiation*, may have loud S₄, mitral regurgitation, S₃ or pulsus bisferiens*

Question 23

Diagnosis of Hypertrophic Cardiomyopathy

Answer 23

1. ECHOCARDIOGRAM: assymmetrical wall thickness (esp septal) > 15mm

systolic anterior motion of mitral valve

• small LV chamber size, dynamic outflow obstruction, + mitral regurgitation*
• 2. ECG: LVH, atrial enlargement, anterolateral & inferior pseudo Q waves*
• 3. CXR: cardiomegaly*

Question 24

Management of Hypertrophic Cardiomyopathy

Answer 24

• Focus on early detection, medical management, surgical and/or ICD placement (implantable cardioverter defibrillator)
• couseling to avoid dehydration & extreme exertion/exercise very important!
• 1.* Medical: BETA BLOCKERS 1st LINE. CCB (Verapamil), Dysopyramide. All 3 are negative inotropes that increase ventricular diastolic filling time. Cautious use of Digoxin, nitrates & diuretics* (Digoxin increases contractility, nitrates & diuretics decrease left ventricular volume)
• 2. Surgical (Myomyectomy): resection of the hypertrophied septum. Myomectomy usually performed in patients with severe, refractory Sx despite medical management*
• 3. Alcohol Septal Ablation: (alternative to surgical management with good outcomes). Medical “myomyectomy”. Ethanol destroys the extra myocardial tissue.*