Cardiovascular Flashcards
Patient presents with BP of 200/120 mm hg,, has dyspnea and is hyperemic. Chest Xray shows pulmonary edema and ECG shows inverted T waves in the inferolateral leads. Which medication should be used?
Nitroglycerin
- A direct venous dilator that reduces preload
- Has vasodilator effects on coronary vessels
- Should be used in the setting of acute cardiac ischemia and pulmonary edema
28 YO pregnant woman is brought to the ER due to elevated BP of 180/90 mm Hg. She is asymptomatic and has a history of preeclampsia. What medication should be given?
Labetalol
- Combined alpha/beta adrenergic blocker
- Safe to use in pregnancy
- Also used in aortic dissection
Preferred medications for patients with preeclampsia or eclampsia?
Labetalol and Nifedipine
Magnesium sulfate is also given IV to avoid seizures
What is the target goal for BP control in women with preeclampsia or eclampsia?
What if the platelet count is below 100,000?
< 160/110 mmHg
< 150/100 mmHg
What is the treatment of choice for cocaine associated acute coronary syndromes?
Alpha adrenergic antagonists
- Phentolamine
Preferred medications for treatment of acute intracerebral hemorrhage caused by hypertensive emergency? Which should be avoided?
- Labetalol, Nicardipine or Esmolol
- Avoid Sodium Nitroprusside and Hydralazine
Preferred medications for treatment of aortic dissection caused by hypertensive emergency? Which should be avoided?
- Labetalol, Nicardipine, Sodium Nitroprusside (add Beta-blocker), Esmolol and Morphine Sulfate
- Avoid Beta-Blocker if aortic regurgitation or suspected cardiac tamponade
What is Fenoldopam used for?
- MOA
- Hypertensive Emergency with Renal Insufficiency (AKI)
- Short acting, selective, peripheral dopamine-1 receptor agonist
- Little or no effect on alpha or beta adrenergic receptors
- Dopamine-1 receptor agonism stimulates adenylyl cyclase and raises intracellular cyclic AMP
- Results in vasodilation of most arterial beds with a decrease in systemic blood pressure
- Renal vasodilation is prominent and increases renal perfusion, diuresis and natriuresis
- IV
When does left ventricular myocardial perfusion occur? Why?
- During diastole
- Because during systole ventricular pressure and wall stress exceed the aortic pressure (120 mm Hg) preventing effective coronary perfusion
- Relaxation during diastole decreases intraventricular pressure (10 mmHg) which is much lower than aortic diastolic pressure (80 mm Hg) providing for adequate perfusion
What happens in the coronary circulation with increased HR?
- It shortens the time of ventricular relaxation
- Time of diastole
- Therefore time available for maximal coronary flow will decrease and becomes a major limiting factor for blood supply
What does phenytoin do to the gums?
- Gingival hyperplasia
- Increases expression of platelet derived growth factor
- When macrophages are exposed to PDGF, they stimulate proliferation of gingival cells and alveolar bone
- May regress after discontinuation of phenytoin
Most common bacterial causes of heart block?
HR is not as fast as we expect it to be
- Legionella
- Lyme disease
- Chagas disease
- Dipththeria
- Typhoid fever
MI with Right Ventricular Failure
- Occurs Acutely
- Hypotension and clear lungs
- Kussmaul sign
MI with Papillary Muscle Rupture
- Occurs within 3-5 days
- Acute, severe pulmonary edema
- Severe mitral regurgitation with flail leaflet
MI with Interventricular Septum/Rupture Defect
- Occurs within 3-5 days
- New holosystolic murmur
- Step up oxygen level between right atrium and ventricle
MI with free wall rupture
- Within 5-14 days
- Pericardial Tamponade
- Jugular venous distension
- Distant heart sounds
- Profound Hypotension is usually cause of death
Where do you find Beta 1 receptors?
- Cardiac tissue
- Renal juxtaglomerular cells
What kind of receptors is a Beta 1 receptor?
- A G protein coupled receptor
- It is associated with Gs
- Increases intracellular levels of cAMP
- Blocking the receptor with a beta blocker decreases levels of cAMP in cardiac and renal tissue
- No effect on vascular smooth muscle since it contains no Beta 1 receptors
How are the lymphatics of the extremities divided?
- Superficial lymphatic vessels
- Follow the venous system - Deep lymphatic vessels
- Follow the arterial system
How are the lymphatics of the lower extremities divided?
- Medial track
- Runs along the saphenous vein to the superficial inguinal lymph nodes
- It bypasses the popliteal nodes
- Lesion to medial track causes inguinal lymphadenopathy - Lateral track
- Communicates with the popliteal and inguinal lymph nodes
- Lesion to the lateral track will cause popliteal and inguinal lymphadenopathy.
Where do the prostate lymphatics drain to?
Into the internal iliac lymph nodes
Where does the scrotum lymphatics drain to?
They drain into the superficial inguinal lymph nodes
Where do the testicular lymphatic drain to?
The para aortic lymph nodes
What are the cardiologic findings in Turner syndrome?
- Bicuspid aortic valve is the most common
- Creates aortic ejection sound, it presents as early systolic, high frequency click heard in the right second intercostal space, sternal border
- The valve may be at risk for stenosis, insufficiency and infectious endocarditis
- Coarctation of the aorta may also be seen in turner syndrome
What will EKG show if electrical impulses are generated below the AV node and his bundle?
- HR can be as slow as 20 BPM
- ECG shows prolonged, abnormally shaped QRS complexes due to aberrant impulse conduction through the ventricles
When can the Av node become the pacemaker?
- When conduction between the SA node and AV node is impaired
- Such as third degree AV block (complete heart block)
- SA node causes atrial contraction and AV causes ventricular contraction independant of each other
- QRS complexes will be narrow since ventricular depolarization proceeds normally
What are the two signs of microembolism seen in infectious endocarditis?
- Splinter Hemorrhages
- Flame shaped hemorrhagic streaks that occur under the nail bed - Janeway lesions
- Small, macular, erythematous or hemorrhagic, non tender lesions on the palms and soles
What are the three main causes of valvular aortic stenosis?
- Calcified normal valve (Most common in US)
- Rheumatic heart disease (Most common worldwide
- Congenitally abnormal valve with calcification
Name a few low molecular weight heparins?
What are they used for?
- Enoxaparin and Dalteparin
- Indirect thrombin inhibitors that bind to antithrombin and convert it from a slow to a rapid inactivator of thrombin and factor Xa.
- Used in patients with acute coronary syndrome
- Such as unstable angina or myocardial infarction
What does the truncus arteriosus give rise to?
Aorta and the pulmonary trunk
What does the bulbus cordis give rise to?
Smooth parts of the left and right ventricles (the outflow tract)
What does the endocardial tissue give rise to?
- Atrial septum
- Membranous Interventricular septu
- AV and semilunar valves
What does the primitive atrium give rise to?
Trabeculated part of the left and right atria
What does the primitive ventricle give rise to?
Trabeculated part of the left and right ventricles
What does the primitive pulmonary vein give rise to?
Smooth part of the left atrium
What does the left horn of the sinus venosus give rise to?
Coronary sinus
What does the right horn of the sinus venosus give rise to?
Smooth part of right atrium (sinus venarum)
What does the right common cardinal vein and right anterior cardinal vein give rise to?
Superior vena cava
What is the first functional organ in embryos and when does it begin to work?
The heart and it beats spontaneously by week 4 of development
When does the heart begin to loop and establish its polarity?
What defects can result during this?
- In week 4 of gestation, the primary heart loops to establish the left and right sides
- Defect in left to right dyenin (in L/R asymmetry) can lead to dextrocardia, seen in Kartagener syndrome (primary ciliary dyskinesia)
Describe the septation of the chambers?
- Septum primum grows toward endocardial cushions, narrowing the foramen primum.
- Foramen secundum forms in septum primum (foramen primum disappears)
- Septum secundum develops as foramen secundum maintains right to left shunt
- Septum secundum expands and covers most of the foramen secundum. The residual foramen is the foramen ovale
- Remaining portion of the septum primum forms valve of foramen ovale
- Septum secundum and septum primum fuse to form the atrial septum
- Foramen ovale usually closes soon after birth because of increase in LA pressure
What is patent foramen ovale?
- Failure of septum primum and septum secundum to fuse after birth
- Most are left untreated
- Can lead to paradoxical emboli (venous thromboemboli that enters systemic arterial circulation) similar to those resulting from an ASD
Describe how the ventricles form?
- Muscular interventricular septum forms, the opening is called the interventricular foramne
- Aorticopulmonary septum rotates and fuses with muscular ventricular septum to form membranous interventricular septum closing interventricular foramen
3 Growth of endocardial cushions seperates atria from ventricles and contributes to both atrial septation and membranou sportion of the interventricular septum.
What is a ventral septal defect?
- Most common congenital cardiac anomality
- Usually occurs in the membranous septum
How does the outlfow tract form?
- Neural crest and endocardial cells migrate
- Truncal and bulbar ridges spiral and fuse to form the aorticopulmonary septum.
3, Ascending aorta and pulmonary trunk form
What are conotruncal abnormalities associated with failure of neural crest cells to migrate?
- Transposition of the great vessels
- Tetrology of Fallot
- Persistent truncus arteriosus
How do the valves develop?
- Aortic/pumonary are derived from the endocardial cushions of the outflow tract
- Mitral/tricuspid are derived from fused endocardial cushions of the AV canal
What causes Pericarditis?
What are the features?
Most commonly caused by viral infections
Also caused by MI (dresslers syndrome), radiation to the chest, metastatic cancer, systemic diseases particularly SLE, other autoimmune disorders and uremia
- Damage leads to the inflammatory process
- Inflammed pericardium reasults in positional and pleuritic chest pain
- Pain is releaved by sitting up
- Pericardium becomes stiff and noncompliant
- You will hear the hearts motion across the pericardium, like a grating noise