Cardiology Flashcards
To measure blood pressure, one must have a mercury sphygmomanometer with a cuff that covers
approximately two thirds of the upper part of the arm or leg.
The intensity of systolic murmurs is graded from I to VI:
I, barely audible;
II, medium intensity;
III, loud but no thrill;
IV, loud with a thrill;
V, very loud but still requiring positioning of the stethoscope at least partly on the chest;
VI, so loud that the murmur can be heard with the stethoscope off the chest
The heart is usually enlarged when the maximal cardiac width is
more than half the maximal chest width (cardiothoracic ratio >50%),
In the posteroanterior view, the left border of the cardiac shadow consists of three convex shadows produced, from above downward, by the
aortic knob, the main and left pulmonary arteries, and the left ventricle
Three structures contribute to the right border of the cardiac silhouette.
from above:
superior vena cava
ascending aorta
right atrium.
Lesions Resulting in Increased Volume Load
those that cause left-to-right shunting: atrial septal defect, ventricular septal defect (VSD), AV septal defects (AV canal), and patent ductus arteriosus
Heart Failure in left to right CHD
- tachypnea, chest retractions, nasal flaring, and wheezing.
- Sympathetic activation leads to sweating and irritability
- the imbalance between oxygen supply and demand lead to failure to thrive.
Lesions Resulting in Increased Pressure Load
due to obstruction to normal blood flow:
- valvular pulmonic stenosis, valvular aortic stenosis, and coarctation of the aorta
- tricuspid or mitral stenosis, cor triatriatum and obstruction of the pulmonary veins.
Characteristic of right-sided heart failure
- hepatomegaly
- peripheral edema
Characteristic of left-sided heart failure
- pulmonary edema
- poor perfusion
Cyanotic Lesions with Decreased Pulmonary Blood Flow
- tricuspid atresia
- tetralogy of Fallot
- various forms of single ventricle with pulmonary stenosis
These lesions must include both an obstruction to pulmonary blood flow (at the tricuspid valve or right ventricular or pulmonary valve level) and a pathway by which systemic venous blood can shunt from right to left and enter the systemic circulation (via a patent foramen ovale, atrial septal defect, or VSD)
Cyanotic Lesions with Increased Pulmonary Blood Flow
Cyanosis is caused by either
1) abnormal ventricular-arterial connections
- Transposition of the great vessels (TGA)
2) total mixing of systemic venous and pulmonary venous blood within the heart
- total anomalous pulmonary venous return (TAPVR)
- truncus arteriosus
Syndrome associated with ASD which includes a hypoplastic or absent radii and a 1st-degree heart block
Holt-Oram syndrome
most common form of ASD
Ostium Secundum Defect
Ostium Secundum Defect
- most often asymptomatic
- subtle failure to thrive
- mild left precordial valve
- enlargement of the RA and RV and dilatation of the PA
- 2nd heart sound is widely split and fixed in its splitting
- ECG: NA or RAD, rsR’ pattern in the precordial leads
In patients with Ostium Secundum ASD, surgical or transcatheter device closure is advised for
- all symptomatic patients
- for asymptomatic patients with a Qp : Qs ratio of at least 2 : 1 or those with right ventricular enlargement
Procedure of choice for ASD
percutaneous catheter device closure
In patients with ASD, closure is not required in
-patients with small secundum ASDs and minimal left-to-right shunts without right ventricular enlargement
True or False:
Small- to moderate-sized ASDs detected in term infants may close spontaneously.
True
True or False:
antibiotic prophylaxis for isolated secundum ASDs is recommended.
False
Infective endocarditis is extremely rare, and antibiotic prophylaxis for isolated secundum ASDs is NOT recommended.
AV septal defect, also known as an AV canal defect or an endocardial cushion defect, consists of
contiguous atrial and ventricular septal defects with markedly abnormal AV valves
Atrioventricular Septal Defects is commonly associated with what syndrome?
Down Syndrome
most common cardiac malformation and accounts for 25% of congenital heart disease
VSD
Most common type of VSD
membranous type
characteristic murmur of a small VSD
- loud, harsh, or blowing holosystolic murmur over the lower left sternal border
- frequently accompanied by a thrill
characteristic of large VSD
- pulmonary blood flow and pulmonary hypertension result to dyspnea, feeding difficulties, poor growth, profuse perspiration, recurrent pulmonary infections, and cardiac failure in early infancy.
- duskiness during infections or crying
- Prominent left precordium
- palpable parasternal lift, a laterally displaced apical impulse and apical thrust, and a systolic thrill.
Typical CXR of VSD
small VSD: normal
large VSD: cardiomegaly with prominence of both ventricles, the left atrium, and the pulmonary artery, increased pulmonary markings, pulmonary effusion, and pulmonary edema
Natural course of VSD:
- 30-50% of small defects close spontaneously during the 1st 2 yr of life
- Small muscular VSDs are more likely to close (up to 80%) than membranous VSDs (up to 35%)
- majority close before 4yo
- infective endocarditis is a long-term risk
True or False
All VSD should be surgically repaired.
False.
Surgical repair is currently not recommended for patients with small VSD.
what should you advise in patients with small VSD?
- should be encouraged to live a normal life, with no restrictions on physical activity
- integrity of primary and permanent teeth should be carefully maintained
Should patients with VSD receive antibiotic prophylaxis for dental and surgical procedures?
antibi otic prophylaxis is no longer recommended for dental visits or surgical procedures
Indications for surgical closure of a VSD include
- 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 because of high risk for aortic valve regurgitation
Leading causative agents for endocarditis in pediatric patients
Viridans-type streptococci (α-hemolytic streptococci) and Staphylococcus aureus
- no underlying disease: Staph
- after dental procedure: viridans Strep
- after lower bowel/ GU manipulation: grp D enterococci
- IV drug user: Serratia marscesens, P. aeruginosa
- indwelling catheter: CoNS
Initiating lesion formed in infective endocarditis which becomes the substrate for the deposition of thrombin and fibrin
nonbacterial thrombotic embolus
- fungating masses >1 cm are at greatest risk for embolization
What criteria are used for the diagnosis of infective endocarditis?
Duke Criteria
2 major criteria, 1 major and 3 minor, or 5 minor criteria suggest definite endocarditis
Major: (+) blood CS, echo evidence of endocarditis (intracardiac mass)
Minor: predisposing conditions, fever, embolic-vascular signs, immune complex phenomena (glomerulonephritis, arthritis, rheumatoid factor, Osler nodes, Roth spots), a single positive blood culture or serologic evidence of infection, and echocardiographic signs not meeting the major criteria
additional minor criteria:
newly diagnosed clubbing, splenomegaly, splinter hemorrhages, and petechiae; a high erythrocyte sedimentation rate; a high C-reactive protein level; and the presence of central nonfeeding lines, peripheral lines, and microscopic hematuria
What is the treatment recommendation for IE?
Target most common organisms: viridans strep and Staphylococci
empiric: vanco+genta
culture-guided:
if highly susceptible, penG or ceftri+penG
or ceftri+genta/vanco
Routine IE prophylaxis for dental procedures is done for which high risk groups?
patients with cardiac conditions, pxs with prosthetic valves, pxs wit previous IE
- prophylaxis for gastrointestinal or genitourinary procedures is no longer recommended in the majority of cases. Prophylaxis for patients undergoing cardiac surgery with placement of prosthetic material is still recommended.
A 1 day old is noted to be cyanotic. PE reveals a grade 2-3/6 systolic murmur and a single loud second heart sound. CXR reveals a normal sized heart and decreased pulmonary vascular markings. ECG left ventricular dominance. The next step in management of this neonate is to administer
a. Sodium bicarbonate
b. Morphine
c. Prostaglandin E1
d. Digoxin
e. Positive pressure ventilation
C
The murmur may represent a PDA. If the PDA closed, marked cyanosis would supervene and result in acidosis, shock and death. PGE1 maintains patency of the ductus arterious between the pulmonary artery and the aorta.
A 1 day old is noted to be cyanotic. PE reveals a grade 2-3/6 systolic murmur and a single loud second heart sound. CXR reveals a normal sized heart and decreased pulmonary vascular markings. ECG left ventricular dominance.
The most likely diagnosis in the patient:
a. PPHN
b. Transposition of the great arteries
c. Truncus arteriosus
d. Pulmonary atresia
e. Total anomalous venous return
D
Pulmonary atresia
Pulmonary atresia is manifested by a small RV, decreased pulmonary vascular markings, early marked cyanosis without heart failure, and ductul dependence to maintain some pulmonary blood flow.
Nelsons 19th Ed
As the ductus arteriosus closes in the 1st hours/days of life, infants with pulmonary atresia and an intact ventricular septum become markedly cyanotic since their only source of pulmonary blood flow is removed. Untreated, most patients die within the 1st wk of life. Physical examination reveals severe cyanosis and respiratory distress. The 2nd heart sound, representing only aortic closure, is single and loud. Often, no murmurs are audible; sometimes a systolic or continuous murmur can be heard secondary to ductal blood flow. A harsh holosytolic murmur may be heard at the lower left sternal border if there is significant tricuspid regurgitation.
3 An 18-month-old is noted to assume a squatting position frequently during playtime at the daycare center. The mother also notices occasional episodes of perioral cyanosis during some of these squatting periods. The day of admission, the child becomes restless, hyperpneic, and deeply cyanotic. Within 10 minutes, the child becomes unresponsive. The most likely underlying lesion is
a. Cardiomyopathy
b. Anomalous coronary artery
c. Tetralogy of fallot
d. Constipation
e. Breath holding spells
C
The child described has TOF with exercise induced cyanosis. The more serious episode is a cyanotic, blue or tet spell and may be due to decreased systemic vascular resistance, increased pulmonary artery pressure, or right ventricular outflow tract obstruction. The murmur of tetralogy (pulmonary stenosis) often disappears or lessens during a spell.
19th Ed
In older children with unrepaired tetralogy, dyspnea occurs on exertion. They may play actively for a short time and then sit or lie down. Children assume a squatting position for the relief of dyspnea caused by physical effort; the child is usually able to resume physical activity after a few minutes of squatting.
Paroxysmal hypercyanotic attacks (hypoxic, “blue,” or “tet” spells) are a particular problem during the 1st 2 yr of life. The infant becomes hyperpneic and restless, cyanosis increases, gasping respirations ensue, and syncope may follow. Temporary disappearance or a decrease in intensity of the systolic murmur is usual as flow across the right ventricular outflow tract diminishes. Severe spells may progress to unconsciousness and, occasionally, to convulsions or hemiparesis. Spells are associated with reduction of an already compromised pulmonary blood flow, which, when prolonged, results in severe systemic hypoxia and metabolic acidosis.