Cardiology Flashcards
What is coarctation of the aorta?
congenital narrowing of descending thoracic aorta
usually noncyanotic
Etiology/Pathophysiology of coarctation of aorta
î LV afterload with SNS activity & RAAS (renin-angiotensis aldosterone system) activation ⇒ HTN, LVH, CHF
70% allso have bicuspid aortic valve**
Clinical Manifestations of coarctation of aorta
** Secondary HTN **
bilateral claudication, dyspnea on exertion, syncope
infants: failure to thrive, poor feedings, shock
Types:
- infantile: preductal*
adult: postductal
Physical Exam findings for coarcation of aorta
- 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)
Diagnosis of coarcation of aorta
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
Management of coarctation of aorta
surgical correction
balloon angioplasty + stent
prostaglandin E1 (PGE1) – preoperatively (reduces symptoms, improves lower extremity blood flow)
What is the most common cyanotic congenital heart disease?
Tetralogy of Fallot
4 factors included in Tetralogy of Fallot
1. RV outflow obstruction (pulmonary artery stenosis)
2. RVH
3. VSD (large unrestrictive)
4. overriding aorta – between ventricles
Clinical Manifestations of Tetralogy of Fallot
* 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)
Physical Exam Findings of Tetralogy of Fallot
* Harsh holosystolic murmur @ left upper sternal border (sounds like pulmonary stenosis)
* Right ventricular heave
* digital clubbing
Diagnosis of Tetralogy of Fallot
* CXR: Boot-shaped heart* (prominent R ventricle)
* ECG: right ventricular hypertrophy*
also right atrial enlargment
*Echo: GOLD STANDARD DIAGNOSIS
Management of Tetralogy of Fallot
surgical repair performed in the first 4 - 12 months of life
PGE1 infusion: prevents ductal closure in cyanotic patients prior to surgery
What is a patent ductus arteriosus?
communication between descending thoracic aorta & pulmonary artery
left to right (noncyanotic)
Pathophysiology of a patent ductus arteriosus
prematurity, perinatal stress & hypoxia delays closure, Rubella infection in the 1st trimester
continued Prostaglandin E1 production promotes patency
Clinical Manifestations of a patent ductus arteriosus
- 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)
Physical Exam Findings of a patent ductus arteriosus
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)
Diagnosis of PDA
CXR: normal or cardiomegaly
ECG: LVH, LAE
Echo: GOLD STANDARD
Management of PDA
IV Indomethacin 1st line
surgical correction if indomethacin fails, best if done before 1 - 3 years of age
What is Hypertrophic Cardiomyopathy?
inherited genetic disorder of inappropriate LV and/or RV hypertrophy (especially septal)
Pathophysiology of Hypertrophic Cardiomyopathy
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)
Clinical Manifestations of Hypertrophic Cardiomyopathy
-
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
Physical Exam of a patient with Hypertrophic Cardiomyopathy
-
_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*
Diagnosis of Hypertrophic Cardiomyopathy
- ECHOCARDIOGRAM: assymmetrical wall thickness (esp septal) > 15mm
systolic anterior motion of mitral valve
- small LV chamber size, dynamic outflow obstruction, + mitral regurgitation*
- ECG: LVH, atrial enlargement, anterolateral & inferior pseudo Q waves*
- CXR: cardiomegaly*
Management of Hypertrophic Cardiomyopathy
- 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)
- Surgical (Myomyectomy): resection of the hypertrophied septum. Myomectomy usually performed in patients with severe, refractory Sx despite medical management*
- Alcohol Septal Ablation: (alternative to surgical management with good outcomes). Medical “myomyectomy”. Ethanol destroys the extra myocardial tissue.*
