CHF

Question 1

What is the problem in CHF?

Answer 1

CHF arises when the ventricles fail to maintain blood circulation, often when the cardiac demand increases.

The heart has no reserve to compensate for the increased burden and blood circulation becomes congested. Typical chief complaints include shortness of breath and peripheral edema.

Question 2

What can precipitate CHF?

Answer 2

Cardiac ischemia or dysrhythmias, infection, PE, physical or emotional stress, noncompliance in medication or diet, volume overload

Question 3

What is the NYHA CHF classification?

Answer 3

Class I – Ordinary activity not limited by symptoms
Class II – Ordinary activity leads to dyspnea, fatigue, etc
Class III – Marked limitation of ordinary activity
Class IV – Symptoms at rest or with any physical activity

Question 4

What is the difference between systolic vs diastolic HF

Answer 4

Systolic dysfunction includes a dilated left ventricle with impaired contractility, typically caused by ischemia, infarction cardiomyopathy, myocarditis, or dysrhythmias. Contrasted with diastolic dysfunction in which the left ventricle remains intact and normal in size, but has an impaired ability to relax, such as with infiltrative cardiomyopathy. Diastolic dysfunction has a better prognosis that systolic dysfunction.

Question 5

Describe the difference between low and high output failure?

Answer 5

In low output failure, there is decreased cardiac output secondary to myocardial damage, such as with ischemia, dilated cardiomyopathy, valvular disease or chronic hypertension. In high output failure, the cardiac output is high or normal, but remains insufficient to supply oxygen demands. This can be found in hyperthyroidism, pregnancy, anemia, AV fistulas, beriberi or paget’s disease.

Question 6

Describe left vs right sided heart failure?

Answer 6

Right sided failure can lead to congestion of pressure and fluid into the right ventricle, resulting in hepatic enlargement, increased JVD and dependent edema. Left sided heart failure will cause congestion of pressure and fluid into the left ventricle, resulting in pulmonary congestion.

Question 7

What is the classic presentation?

Answer 7

The most classic presentation for CHF includes dyspnea, especially with exertion. sensitivity of 100% and specificity 17%. Also, orthopnea (sensitivity 88%, specificity 50%) or paroxysmal nocturnal dyspnea (sensitivity 39%, specific 80%).

If sputum, pink and frothy. Lower extremity swelling.

Question 8

PE

Answer 8

Diaphoretic, HTN, JVD (greater than 4 cm), rales secondary to alveolar edema, wheezing (peribronchial edema), pitting edema in lower extremities and abdomen, S3 gallop

Question 9

Imaging CXR

Answer 9

• Cardiomegaly and effusions
• Note, CXR can lag 12 hours. 20% do not show any pulmonary edema on CXR at all.
• Peribronchial cuffing and perihilar congestion
• Cephalization (fluid in upper lobes) ONLY seen on Upright
• Kerley B-lines - dilated lymphatic channels, peripheral and horizontal

Question 10

BNP

Answer 10

• 90% sensitive and 76% specific
  < 100 Unlikely CHF
  100-500 Potentially CHF, although could also be PE,
  Pulmonary HTN, ESRD, cirrhosis, or hormone replacement therapy
  >500 Most likely CHF
• Release stimulated by high ventricular filling pressures. Has a diuretic effect and antihypertensive effect, by increasing the amount of sodium in the urine.

Question 11

Echocardiogram

Answer 11

Normal ejection fraction is 55-75%. Patients with severe CHF may have EF less than 20%. Echocardiogram can also be used to visualize ventricular size and any wall abnormalities or valvular pathology, pericardial thickening, tamponade or constrictive pericarditis as additional contributors to CHF

Question 12

ED treatment

Answer 12

• Normotensive patients: Give rapid acting nitrates to vasodilate, may be given sublingual, IV, or transdermal with nitropaste. IV Morphine can be given for chest pain and to increase vasodilation. IV diuretics, such as Lasix, can increase urine output.
• Hypertensive patients: Add Nitroprusside IV drip for severe, persistent hypertension.
• Hypotensive patients: Avoid nitrates and morphine, as they will drop the blood pressure even loser. Instead, increase myocardial contractility with dopamine, dobutamine, norepinephrine, amrinone or milrinone.
• Severe or Chronic low output CHF: Use ACE inhibitors to increase hemodynamic stability and exercise capability.
• Diastolic CHF: Calcium channel blockers may help, but do not use in patients with concurrent, depressed left ventricular function, as this may increase mortality and recurrence of CHF.