Cardiovascular Flashcards
What type of shunt produces early cyanosis?
What is the usual treatment?
Causes?
Right-to-left shunts.
Urgent surgical correction and/or maintenance of PDA.
5 T’s:
- Truncus arteriosus (1 vessel)
- Transposition (2 switched vessels)
- Tricuspid atresia (3 = tri)
- Tetralogy of fallot (4 = tetra)
- TAPVR (5 letters in name)
Neonate presents with cyanosis at birth and dies.
Autopsy shows a single great vessel that supplies the lungs and systemic circulation. What disease was present?
Persistent Truncus Arteriosus.
Most patient have accompanying VSD.
A concerned mother brings her newborn to you because she thinks the baby is turning blue.
An echocardiogram shows the aorta leaving the right ventricle and the pulmonary trunk leaving the left ventricle.
What is that disease? What must be associated for the child to have survived to this age?
D-transposition of the great vessels.
Failure of the aorticopulmonary septum to spiral.
There must be a VSD or PDA, or patent foramen ovale to produce a shunt and allow mixing of blood (needed so systemic circulation can get oxygen!).
Without surgical intervention, most infants die within the first few months of life.
What defects are associated with tricuspid atresia?
Absence of tricuspid valve and hypoplastic RV.
Requires an atrial septal defect and ventricular septal defect for viability.
Early cyanosis.
What defects are associated with Tetralogy of Fallot?
PROVe
- Pulmonary infundibular stenosis (most important determinant for prognosis)
- RVH - boot shaped heart on CXR
- Overriding aorta
- VSD
Caused by anterosuperior displacement of the infundibular septum.
Most common cause of early childhood stenosis.
What is the etiology of cyanosis in tetrology of fallot?
How does squatting affect a patient with tetrology of fallot?
What is the treatment for this disease?
Cyanosis due to pulmonary stenosis forcing right-to-left flow across VSD. Causes “tet spells” and right-ventricular hypertrophy.
Squatting increases systemic vascular resistance, reduces right-to-left shunt, and improves cyanosis.
Treat with early surgical correction.
Neonate presents with cyanosis.
Echocardiogram discovers an ASD and that the pulmonary veins drain into the right heart circulation.
What is this disease?
Total anomalous pulmonary venous return (TAPVR)
Pulmonary veins will drain into the SVC, coronary sinus, etc instead of the left atrium.
Associated with ASD and sometimes PDA to allow for right-left shunting to maintain cardiac output.
What conditions result in late cyanosis (“blue kids”).
List in order of frequency
Ventricular septal defect (VSD) > Atrial septal defect (ASD) > Patent ductus arteriosus (PDA)
Is a VSD typically symptomatic at birth?
What is the usual course?
VSD usually asymptomatic at birth, manifests weeks late ror remain asymptomatic throughout life.
Most will self-resolve. Larger lesions cause LV overload and heart failure.
A defect in what is the most common cause of ASD?
What might you hear on auscultation?
Defect in the septum secundum most common cause of isolated ASD. (Defects in the septum primum associated with other anomalies).
Might hear loud S1; wide, fixed split S2.
May be asymptomatic or cause heart failure.
Different than patent foramen ovale - septae are missing rather than unfused.
Neonate presents with late cyanosis. You hear a “machine like murmur” on auscultation.
Pathogenesis of this disease?
Patent ductus arteriosus.
Fetal period, shunt is from right to left (normal) to bypass lung circulation.
In neonatal period, lung resistance decreases, shunt becomes left to right, RVH and/or LVH and heart failure occurs.
What can you use to close a PDA?
What could you use to maintain patency? When would you want to do that?
Endomethacin (indomethacin) ends patency of PDA
PGE kEEps it open - use to sustain life in conditions such as transposition of the great vessels.
(Low O2 tension also keeps PDA open)
A child presents with cyanosis, clubbing, and polycythemia.
Echocardiography reveals a VSD.
What is this condition?
Eisenmenger syndrome.
An uncorrected left-to-right shunt (VSD, ASD, PDA) increases pulmonary blood flow which induces remodeling of the vasculature and pulmonary arterial hypertension.
Right ventricular hypertrophy occurs to compensate and shunt becomes right to left.
An infant with Turner syndrome presents with a systolic click and a delayed femoral pulse as compared with the brachial pulse.
Infantile type coarctation of the aorta.
Aorta narrowing is proximal to insertion of the ductus arteriosus (preductal). Associated with bicuspid aortic valve (systolic click) and other heart defects.
Infantile: In close to the heart.
An adult presents with notching of the ribs, hypertension in the upper extremities, and weak, delayed pulses in lower extremities (radiofemoral delay).
Adult-type Coarctation of the aorta.
Aorta narrowing is distal to ligamentum arteriosum (postductal)
Adult: Distal to ductus.
What congenital heart defects are associated with 22q11 syndromes?
Include DiGeorge, velo-cardio-facial syndrome, Shprintzen syndrome, conotruncal anomaly face syndrome, Strong syndrome, congenital thymic aplasia, and thymic hypoplasia. Due to small deletion in chromosome 22.
Truncus arteriosus, tetralogy of Fallot.
What congenital heart defects are associated with Down syndrome?
ASD, VSD, AV septal defect (endocardial cushion defect)
What congenital heart defects are associated with congenital rubella?
Septal defects, PDA, pulmonary artery stenosis.
What congenital heart defects are associated with Turner syndrome?
Bicuspid aortic valve, coarctation of aorta (preductal)
What congenital heart defects are associated with Marfan syndrome?
MVP (mitral valve prolapse), thoracic aortic aneurysm and dissection, aortic regurgitation.
What congenital heart defects are associated with an infant of a diabetic mother?
Transposition of the great vessels.
What values define hypertension?
Risk factors?
Systolic BP > 140 mmHg and/or diastolic BP > 90mmHg
Age, obesity, diabetes, smoking, genetics, black > white > Asian.
Young patient presents with hypertension. Angiography shows a “string of beads” appearance of the renal artery.
Fibromuscular Dyplasia
What are some causes of hypertension?
90% is primary (essential) and related to increased cardiac output or total peripheral resistance.
Remaining 10% mostly secondary to renal disease, including fibromuscular dysplasia in younger patients.
What defines hypertensive emergency?
Severe hypertension (> 180/120 mmHg) with evidence of acute, ongoing organ damage (e.g., papilledema, mental status changes)
What conditions does hypertension predispose to?
Atherosclerosis, LVH, stroke, CHF, renal failure, retinopathy, and aortic dissection.
Picture below shows hypertensive nephropathy - Renal artery hyalinosis by PAS stain.
Patient presents with yellow plaques and nodules of in the skin and eyelids.
What are these lesions called? What’s in them? What is the underlying derangement?
Skin - xanthomas
Eyelids - xantholasma
Composed of lipid-laden histiocytes.
Reflect underlying hyperlipidemia.
Patient presents with a thickened knobbly achilles tendon.
Biopsy shows lipid deposits.
Tendinous xanthoma
A sign of hyperlipidemia
Patient presents with a white corneal ring.
What is this called? What does it reflect?
A corneal arcus. Can be a white, gray, or blue opaque ring around the cornea.
Caused by lipid deposit in the cornea. Presents early in life with hypercholesterolemia. Common in elderly (arcus senilis).
Patient presents with “pipestem” arteries on x-ray.
Your attending says there is calcification in the media of the arteries.
What is this condition?
Monckeberg arteriosclerosis (medial calcific sclerosis)
Usually benign, does not obstruct blood flow, intima not involved.
What are the two types of arteriolosclerosis?
What causes each?
Hyaline arteriolosclerosis: Thickening of small arteries in essential hypertension or diabetes mellitus
Hyperplasic arteriolosclerosis: Seen in severe hypertension
Disease characterized by thickening of large-and-medium muscular arteries and elastic arteries with cholesterol deposits in the arterial wall.
Risk factors?
Atherosclerosis
Forms atherosclerotic plaques with cholesterol crystals.
Modifiable Risk factors: Smoking, hypertension, hyperlipidemia, diabetes
Non-modifiable: Age, sex (higher in men and postmenopausal women), family history
What is the pathogenesis of an atherosclerotic plaque?
Inflammation important in pathogenesis.
Endothelial cell dysfunction -> macrophage and LDL accumulation -> foam cell formation -> fatty streaks -> smooth muscle migration (PDGF and FGF), proliferation and extracellular matrix deposition -> fibrous plaque -> complex atheromas
What are complications of atherosclerosis?
Aneurysm, ischemia, infarcts, peripheral vascular disease, thrombosis, emboli
What are the most common locations for atherosclerosis?
Abdominal aorta > coronary artery > popliteal artery > carotid artery
What are some symptoms of atherosclerotic plaques?
Angina, claudication, or asymptomatic.
What is an aortic aneurysm?
Localized pathogenic dilation of the aorta.
Pain is a sign of leakage, dissection, or imminent rupture.
What is associated with abdominal aortic aneurysms?
Atherosclerosis. More frequently in hypertensive male smokers > 50 years old.
What is associated with thoracic aortic aneurysms?
Cystic medial degeneration due to hypertension (older patients)
Marfan syndrome (younger patients)
Tertiary syphilis (obliterative endarteritis in vasa vasorum)
Patient presents with tearing chest poain radiating to the back and unequal blood pressure in the right and left arms.
CXR shows mediastinal widening.
CT shows this finding.
Aortic dissection - an intraluminal tear forming a false lumen.
Associated with hypertension, bicuspid aortic valve, and inherited connective tissue disorders (Marfan syndrome).
False lumen can be limited to ascending aorta, propagate from ascending aorta or propagate from the descending aorta.
Can result in pericardial tamponade, aortic rupture, and death.
Patient presents with chest pain that worsens with exertion and resolves with rest.
ST depression is seen on ECG during exertion.
Stable angina - usually secondary to coronary artery atherosclerosis.
Patient presents with chest pain that shows transient ST elevation on ECG.
He reports it sometimes happens when he smokes.
Varient angina (Prinzmetal) - due to coronary artery spasm.
Triggers include tobacco, cocaine, and triptans, but trigger often unknown.
Give calcium channel blockers, nitrates, and smoking cessation.
Patient presents with chest pain that comes and goes and sometimes affects him at rest.
ST depression is seen on ECG
Unstable/crescendo angina. Thrombosis with incomplete coronary artery occlusion. Increase in frequency or intensity of chest pain; any chest pain at rest.
What is coronary steal syndrome?
Distal to coronary stenosis, vessels are maximally dilated at rest.
When a vasodilator is given (dipyridamole, regadenoson), blood is shunted towards well-perfused area which decreases flow and causes ischemia in the poststenotic region.
Principle behind pharmacologic stress tests.
Patient presents with diaphoresis, nausea, vomiting, severe retrosternal pain, pain in the left arm and jaw, shortness of breath, and fatigue.
Lab tests show elevated troponin.
How to differentiate between variants of this disease?
Pathogenesis?
Myocardial infarction
Acute thrombosis due to coronary artery atherosclerosis with complete occlusion of coronary artery and myocyte necrosis.
Transmural infarction: ECG will show ST elevation
Subendocardial: ECG may show ST depressions
What is the most common cause of sudden cardiac death?
Associated diseases?
Sudden cardiac death: Death within 1 hour of onset of symptoms.
Most often due to a lethal arrhythmia (e.g., ventricular fibrillation).
Associated with CAD, cardiomyopathy (hypertrophic, dilated), and hereditary ion channelopathies (long QT syndrome)
What is seen by gross examination and light microscopy from 0-4 hours after the start of an MI?
No changes can be identified.