CHF & Nitrates

Describe CHF to me.

A clinical syndrome w/ volume overload & dec. tissue perfusion

Seen when heart is unable to pump enough blood to meet requirements of the body-- blood gets backed up

When is CHF usu seen?

In pt's w/ end stage heart disease

Pt's w/ valvular disease, uncontrolled HTN, CAD, vent. dysfunction, ischemic disease

What is the **Cause of CHF?

CHF usu originates as a LEFT-SIDED VENT. DISEASE*

The left vent is mc affected by HTN, valvular dysfunction, CAD

We then see a snowball effect

What's going on in an acute form of HF?

Large percent systolic

Sudden reduction in CO leading to pulm edema & systemic hypotension w/o peripheral edema

EX: MI, ruptured papillary muscle, HTN crisis, acute aortic insuff.

What's going on in a chronic form of HF?

Usu seen w/ dilated cardiomyopathy & multivalvular disease

The primary source of BNP is from where? It is secreted in the response to what? What does it cause?

Primary source of BNP is the cardiac ventricles

Secretions occur in the response to vasocon., salt and water retention

Causes an inc. in GFR & acts as an endogenous vasodilator

Inc. serum BNP is seen with HF.

What is the Nonpharm. TX to CHF?

Low Salt Diet

Fluid restriction

Daily Weight (early morning, no clothes, same scale)

Cardiac Rehab

Pt. Education

And NO EtOH (bummer).

Important labs to monitor in a pt. with CHF are?

Lytes, BUN/Creat

BNP

CBC

LFT, LIPIDS

A1C

PT

TSH

ABG

UA

Mg

What's a good study to run on CHF pt's?

Echo!

What drugs do you want to use to tx CHF pt's?

ACEI's

ARBs

Diuretics

Digitalis

Selective BB's

Anticoag Tx (Coumadin)

BB's are a better choice as they provide both antiHTN and antiarrythmic effects, but do you want to give them to a pt in ACUTE CHF?

NO! Only give BB's to a pt with stable CHF

How do you want to start BB therapy on a pt in HF?

If they have mild to mod HF and are already receiving ACEI, diuretic, +/- Dig, +/- Aldos. antag

Start LOW and SLOW. Titrate Q 2 weeks

Counsel pt

A Cardiac Glycoside such as Digoxin Inhibits what and stimulates what?

Inhibits the Na+/K+ ATPase causing inc. force of contraction

It Stimulates the Vagus Nerve: dec. the firing rate of the SA node, decreasing the HR and cardiac conduction velocity

What are some Adverse Effects of Digoxin?

GI: Anorexia, N/V/D, abd discomfort

CNS: HA, weakness, apathy, drowsy, *VISUAL DISTURBANCES(halo, blurred vision)*, depression, delirium

Cardiac: "tachy-brady" arrhythmia, especially Vtach and PVC's, AV block. M/c cause of death on digoxin toxicity is from V fib

$D/C dig immediately if you suspect an OD and give them K+ & digibind

What are some drug interactions w/ Digoxin?

Quindine and Verapamil can increase dig levels

BB's- can result in complete heart block

Antacid- reduces dig abs.

Thyroid hormones may dec therapeutic effectiveness of dig so monitor them

What are some indications for Nitrates?

HTN

Angina

CHF

MI

What do Nitrates do?

Causes systemic vasodilation of med & large coronary vessels

Inc. myocardial O2 supply

Dec. myocardial O2 demand

Dec. myocardial wall tension

Dec. Preload

What is an indication for Nitro-dur (Transdermal-Nitro)

Indicated for prophylaxis of angina; NOT indicated for acute attacks

Not for Peds cases

What is an indication for Nitrolingual (Nitro spray)?

Indicated for prophylaxis of angina; NOT indicated for acute attacks (watch pt's BP with sprays)

Not for Peds cases

What is an indication for S/L Nitrate: Nitroglycerine (Nitrostat)

Indicated for prophylaxis and treatment of angina INCLUDING acute attacks

Not for Peds cases

What is an indication for Oral Nitrate: Isosorbide Dinitrate (Isordil)

Indicated for prophylaxis and treatment of angina; NOT indicated for an acute attack. Titrate dose scored oral tabs.

Not for Peds cases

Nitrates Contraindications, Precautions, SE's?

Do NOT chew/crush tabs

Caution in recent AMI, hypotension volume depletion, hypertrophic cardiomyopathy

NOT for nursing mommy's

Avoid abrupt cessation, tolerance may develop

Hypotension potentiated w/ EtOH, CCBs, vasodil's

SE: HA, flushing, dizzy, weak, rash, Otho hypo, paradox brady