CHF Flashcards
What is cardiac output?
amount of blood left in the ventricle
What is cardiac preload?
Pressure in the right side of the heart as blood returns to the heart
What is cardiac afterload?
Pressure the heart must pump against within the arterial system to eject blood (Peripheral vascular resistance)
At the hemodynamic level, what causes impaired contractility?
Loss of cardiac muscle cells, Beta receptor down-regulation, and reduced ATP production
Systolic Dysfunction
Is usually the result of an MI. Evidenced by low ejection fraction and reduced inotropy during ventricular systole.
Diastolic Dysfunction
Usually caused by HTN and IHD. Decreased myocardial noncompliant decreasing filling. Low CO with normal ejection fraction.
Who is more likely to develop diastolic dysfunction?
Elderly, women, and those with a history of MI
What favourable effect does increased sympathetic activity have?
Increased HR, Increased contractility, vasoconstriction causing increased venus return and filling
What unfavourable effect does increased sympathetic activity have?
Arteriolar constriction, afterload,increased workload, increased O2 consumption
What favourable effect does increased Renin-Angiotension Aldosterone have?
Salt and water retention, increased VR
What unfavourable effect does increased Renin-Angiotension Aldosterone have?
Vasoconstriction causing increased afterload
What favourable effect does increased IL-1 and TNF-Alpha have?
May have roles in myocyte hypertrophy and LV remodeling
What unfavourable effect does IL-1 and TNF-Alpha have?
Apoptosis
What favourable effect does increased endothelin have?
Vasoconstriction causing increased VR
What unfavourable effect does increased endothelin have?
Increased afterload
What are the BACKWARD effects of LVF?
dyspnea on exertion, orthopnea, cough, paroxysmal nocturnal dyspnea, cyanosis, basilar crackles
What are the FORWARD effects of LVF?
Fatigue, oliguria, increased heart rate, faint pulses, restlessness, confusion, anxiety
What are the BACKWARD effects of RVF?
Hepatomegaly, ascites, splenomegaly, anorexia, subcut edema, jugular vein distention
What are the FORWARD effects of RVF?
Fatigue, oliguria, increased heart rate, faint pulses, restlessness, confusion, anxiety
How many classes of heart failure are there according to the NYHA?
4
Class 1 of heart failure
no limitation. Normal physical exercise does not cause fatigue, dyspnoea or palpatations.
Class 2 of heart failure
Mild limitation. Comfortable at rest but normal physical activity produces fatigue, dyspnoea or palpatations
Class 3 of heart failure
Marked limitation. Comfortable at rest but less gentle physical activity produces marked symptoms of heart failure.
Class 4 of heart failure
Symptoms of heart failure occur at rest and are exacerbated by any physical activity
What is a diagnosis of CHF based upon?
Past medical history, physical examination, laboratory and radiologic findings
What does a blood test use to diagnose CHF?
CBS, Liver biochemistry, cardiac enzymes, BNP, and thyroid function
How does echocardiography diagnose CHF?
It establishes the presence of systolic and/or diastolic impairment of the left or right ventricle to determine the EF.
Importance of Brain Natriuretic Peptide in CHF
The hormones pro-BNP and BNP are highly accurate for identifying or excluding HF with high specificity and sensitivity. Particularly valuable in differentiating cardiac from pulmonary causes of dyspnea.
What is the Major Framingham Criteria for diagnoses of CHF?
PND, Neck vein distention, rales, cardiomegaly, acute pulmonary edema, S3 gallop, increased venous pressure, and positive hepatojugular reflux
What is the minor Framingham criteria for diagnoses of CHF?
Extremity edema, night cough dyspnea on exertion, hepatomegaly, pleural effusion, vital capacity reduced by 1/3 from normal, tachycardia (>120 bpm). Weight loss > 4.5kg over 5 days of treatment.
To establish a clinical diagnosis of CHF using the Framingham criteria a patient must exhibit…
at least one major or two minor criteria are required.
Beta blockers in CHF should be used if
stable and no fluid overload.
How does a beta blocker work on CHF?
Makes you feel weak and tired for a few days then stable. Reduce HR and BP through SNS to decrease consumption of O2 of the heart muscle
What do ACE inhibitors/ ARBS do in CHF
Vasodilate, counteract RAAS
When should you use a diuretic in CHF?
If volume is overloaded. It decreases preload, blood pressure and edema
What does digoxin do in CHF?
Decreases HR and enhances contractility
When should you use Aldactone and what does it do?
You should use aldactone if you are still symptomatic and have low K+. It decreases Na retention.
Non-pharm measures for CHF
Moderate aerobic exercise
Sodium restriction (2-3g/day, 1-2g if advanced HF)
1.5-2L of fluid/day
Daily weighing
Flu and pneumonia vaccines
Close supervision and follow-up
