Term
| What are some common congenital heart defects? |
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Definition
*ventricular septal defects (VSD) *tetralogy of fallot *AV canal defects *coarctation of the aorta *hypoplastic left heart syndrome NOTE - 1 in 3 birth defect deaths are due to CHD |
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Term
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Definition
*Shunts are loci where red (oxygenated) and blue (deoxygenated) blood mix ex - ductus venosus, ductus arteriosus |
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Term
| Compare blood flow to the lungs before and after birth |
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Definition
*before birth lungs only receive ~7% of CO because no gas exchange is occuring; only need blood for growth *after birth 100% of CO passes through the lungs NOTE - pulmonary vascular resistance is very high before birth and it lowers dramatically after birth |
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Term
| What causes congenital defects to result in left to right shunts? |
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Definition
| as long as the pulmonary blood flow is unobstructed, the lower pulmonary vascular resistance that occurs after birth causes the L to R shunts |
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Term
| What is the most common shunt lesion? |
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Definition
| Ventricular septal defect (VSD) |
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Term
| Contrast the mitral and tricuspid valves |
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Definition
*mitral valve (LA -> LV) few or no attachments to ventricular septum (attaches to the free wall) continuity between aortic valve and mitral valve *tricuspid valve (RA -> RV) has attachments to the ventricular septum muscle layer lies between tricuspid valve and pulmonary valve |
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Term
| How does VSD affect the lungs? |
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Definition
pulmonary edema the left to right shunt causes there to be more blood going through the pulmonary system than the lungs can handle |
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Term
| When is surgery indicated in patients with VSD? |
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Definition
*VSD is unrestrictive (pressure is approximately equal between right and left ventricles) *left to right shunt is 2:1 or greater *aortic valve distortion results in aortic insufficiency |
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Term
| What is the worst consequence of increased pulmonary blood flow? |
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Definition
*pulmonary vascular disease *there are permanent, progressive, and ultimately lethal changes in pulmonary arteriolar structure |
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Term
| What is eisenmerger's syndrome? |
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Definition
*severe pulmonary vascular disease resulting from a longstanding unrestrictive shunt *pulmonary vascular resistance is greater than systemic vascular resistance resulting in right to left shunting *signs - clinical cyanosis and polycythemia |
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Term
| What is hypoplastic left heart syndrome? |
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Definition
*left side of the heart - aorta, aortic valve, mitral valve, left ventricle - is underdeveloped *blood returning from the lungs must flow through an atrial septal defect to the right side. blood reaches the aorta from the pulmonary artery via patent ductus arteriosus |
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Term
| What is congestive heart failure? |
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Definition
| *abnormality of cardiac function that leads to the inability of the heart to pump blood to meet the body's basic metabolic demands or when it can do so only with an elevated filling pressure |
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Term
| What are some of the causes of CHF? |
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Definition
*common causes coronary artery disease leading to ischemia (~70%) hypertension *less common causes diabetes mellitus valvular disease |
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Term
| What are some signs of CHF that can show up in a physical exam? |
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Definition
*paroxysmal nocturnal dyspnea - shortness of breath when laying down *rales - sound in the lungs which indicates the presence of fluid *pulmonary edema |
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Term
| How is pulmonary congestion caused in CHF? |
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Definition
| *increased hydrostatic pressure due to increased blood volume -> increased filtration |
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Term
| How is the volume pressure curve changed in CHF? |
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Definition
*curve shifts down and to the right *vasodilators are used to shift the curve back to normal |
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Term
| What are the adverse effects of sympathetic activation relating to CHF? |
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Definition
*chronic adrenergic stimulation promotes cardiotoxicity and CHF |
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Term
| What are some of the neurohumoral mediators of CHF? |
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Definition
*NE *angiotensin II lead to vasoconstriction, sodium retention, and ventricular remodeling |
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Term
| What are the different drugs associated with the different stages of heart failure? |
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Definition
*stage A - high risk, no symptoms treat causes like hypertension, ACE inhibitor Stage B - structural heart disease ACE inhibitors, beta blockers in some patients Stage C - structural disease + symptoms ACE inhibitors, beta blockers, digoxin, diuretics before Stage D aldosterone antagonist, revascularization Stage D - refractory symptoms requiring special intervention inotropes, transplantation |
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Term
| What's the sequence in heart failure |
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Definition
| risk factors -> vascular dysfunction -> vascular disease -> tissue injury -> pathological remodeling (LV hypertrophy) -> CHF |
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Term
| What are some of the common drugs used to treat CHF? |
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Definition
*ACE inhibitors - block the RAS system *beta-blockers *aldosterone antagonists |
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