Download Treatment of CHF

TREATMENT OF CHF
Caleb Hale, M.D.
I.
II.
July, 2005
MAKING THE DIAGNOSIS IN SUSPECTED HEART FAILURE. Early diagnosis is critical to optimal management.
Heart failure is the result of a complex and inter-related series of responses to myocardial injury that results in
remodeling which ultimately leads to dysfunction. Impacting this cycle early favors outcomes and prognosis.
A. Heart failure SUSPECTED because of signs/symptoms (doe, peripheral edema):
1. ECG: any evidence of dz? Poor prognostic indicators include: Wide QRS, low limb-lead voltages,
extensive Q waves, arrhythmias (all potential signs of advanced CAD – the predominant etiology of HF).
2. CXR: look for pulmonary edema, cephalization of flow.
3. BNP(pg/mL) (where available): <100 = no significant failure; 100-250 significant LV dysfunction, but
compensated congestion; 250-500 CHF with systolic and diastolic dysfunction; 500-1000 decompensated
CHF; >1000 substantial CHF (note: the use of this assay in screening for heart failure is being evaluated.
If the diagnosis is uncertain, however, a level less than 100 has a high negative predictive value. Also
can be used to follow effects of therapy longitudinally.
4. If the above are normal, the likelihood of failure is LOW.
B. Abnormal results on any of the above?: perform ECHO. Can show evidence systolic and/or diastolic dysfunction,
focal vs. global wall-motion abnormalities, hypertrophy, valvular disease, tamponade, effusion, hemodynamics
(including an estimation of EF: >55% is normal; in most cases of systolic dysfunction leading to HF, the EF is less
than 40%), and anatomy. If this test is normal, then HF is VERY UNLIKELY.
C. If ECHO reveals abnormality, the next task is to assess the ETIOLOGY and DEGREE of dysfunction and any
CONTRIBUTING FACTORS. Initial evaluation should include:
1. Hx/PE: sensitive exam findings: JVD, S3 gallop. Other common: edema, rales, dyspnea, orthopnea,
PND.
2. CBC (anemia? infection? evidence of malignancy?)
3. Urinalysis (evidence of renal dysfunction? Other etio. of fluid retention?)
4. Chem-10 (electrolyte abnormalities?, evidence of renal failure?, evidence of diabetes [a CAD
equivalent]?)
5. Coags, Albumin, LFTs (evidence of hepatic congestion/dysfunction [fluid retention]?)
6. CXR and 12-lead ECG (if not already done) – evidence of ischemic HD? vascular redistribution
(cephalization of flow)?, cardiomegaly?
7. Consider baseline BNP measurement.
8. TFTs
9. Other tests as indicated based on suspected etio - ex: ferritin/transferrin for Hemochromatosis, assays for
CTDs etc.
STAGING of Heart Failure
A. The ACC and AHA Classifiation Scheme for the Staging of Heart Failure (not to replace the NYHA ‘Functional
Classification’ which applies to stages C and D of the following):
1. Stage A: NO STRUCTURAL DISEASE. At risk for the development of Heart Failure because of
comorbidities, but WITHOUT current structural or functional abnormalities of the heart, and without any
signs of symptoms of failure. Examples: HTN, DM, CHD, Cardiotoxin exposures, family hx. of DCM,
Hx. rheumatic fever, hemochromatosis.
2. Stage B: NO SYMPTOMS. Overt heart disease that is strongly associated with the development of heart
failure but WITHOUT signs or symptoms of failure. Examples: ventricular hypertrophy, chamber
dilation, asymptomatic valvular disease, prior MI, anginal symptoms.
3. Stage C: SYMPTOMS. Patient with PRIOR or CURRENT symptoms of failure associated with
structural/functional heart disease. Examples: DOE, fatigue, edema, fluid retention.
4. Stage D: REFRACTORY SYMPTOMS. Advanced structural/functional heart disease and marked
symptoms of failure AT REST despite maximal treatment and requiring specialized interventions.
Examples: frequent hospitalizations for CHF exacerbations, hospital-bound on inotropes, transplant
candidacy, hospice patients (due to heart failure).
B. The NYHA Functional Classification – applies to those with STAGE C or D disease:
1. Class I: No symptoms or limitations in activity.
2. Class II: Mild symptoms and slight limitations in activity, comfortable at rest.
3. Class III: Marked limitations in activity due to symptoms, comfortable at rest.
4. Class IV: Severe limitations, with symptoms even at rest.
III.
The Treatment of Heart Failure Due to Systolic Dysfunction:
A. Treatment of Heart Failure by Stage:
1. Stage A (No Structural Disease or Symptoms): Risk factor modification and optimization: treat HTN,
smoking cessation, avoidance of cardiotoxins, lipid profile optimization, exercise prescription, ACE-I
where appropriate/tolerated.
2. Stage B (Structural Disease, Asymptomatic): All measures above, ACE Inhibitors and Beta Blockers as
long as can be tolerated – note: the early initiation of these agents may delay or prevent progression to
stages C and D.
3. Stage C (Symptoms Develop): All measures above, ACE, BB (when stable and compensated), Diuretics
(loop, aldosterone antagonism if indicated – see below), Neseritide (indicated in decompensated patients
who have already been on high-dose diuretics), Digoxin if AF (optional in sinus rhythm), Salt
Restriction, Fluid Restriction, Immunization against Influenza and Pneumococcus. Moderate aerobic
exercise except during periods of acute decompensation, and: WITHDRAWAL OF DRUGS KNOWN
TO ADVERSELY AFFECT THE CLINICAL OUTCOME IN HEART FAILURE:
i.
NSAIDs
ii.
Most antiarrhythmic agents
iii.
Most CCBs
iv.
Glitizone Insulin Sensitizing Agents.
4. Stage D (Refractory Symptoms): All of above measures, and, as indicated: mechanical assist devices,
heart transplantation, Neseritide, IV inotropic infusion (continuous, not intermittent), admission for
titration of medications under invasive hemodynamic monitoring, hospice. Consider referral to a Heart
Failure Specialist or for Heart Transplantation Evaluation when:
i.
Frequent decompensation requiring admission or ED visits
ii.
Difficulty determining volume or end-organ perfusion status
iii.
Complex HF with CKD, hepatic congestion, severe pulmonary hypertension, systemic
hypoperfusion, congenital abnormalities.
iv.
When considering biventricular pacing or defibrillator placement.
v.
Stage D but of reasonable age and without significant co-morbidity where transplantation may
be feasible.
B. Fundamentals of Therapy:
1. Diuretics to achieve euvolemia.
2. ACE inhibitors in ALL TOLERANT PATIENTS; If intolerant – use ARB (LIFE study). Where
intolerant of these, can use HYDRALAZINE and ISOSORBIDE DINITRATE for similar afterload
reduction effect.
3. Select Beta-Blockers in STABLE COMPENSATED failure.
C. Adjunctive Therapies:
1. Electrolyte optimization/supplementation.
2. Digitalis (digoxin) –with Atrial Fibrillation in Stage C or D (optional in sinus rhythm, but no good trials
to support this use); maintain level < 0.7 ng/mL.
3. Aldosterone blockade (spironolactone) as shown in RALES trial: for patients older than 65 with NYHA
Fn. Class III or IV failure/AHA Stage C or D and Cr less than 2.5.
4. Neseritie: IV infusion of B-type natiuretic peptide indicated in acutely decompensated heart failure in a
patient who has already been taking high-dose diuretics.
5. IV inotropic agents, not intermittently, but continuous IV (ex. Dobutamine).
D. Other Pharmacologic Considerations:
1. Control of systolic and diastolic pressure.
2. Optimization of lipid profile.
3. Treatment/management of arrhythmias. If antiarrhythmic indicated for ventricular arrhythmia,
AMIODARONE is recommended – although need to monitor closely for excessive bradycardia (if used
in conjunction with beta blockade), and for thyroid and hepatic toxicity.
4. Treatment of thyroid disorders.
E. Pharmacologic Therapies in which there is LITTLE EVIDENCE OF EFFICACY and in which there MAY BE
EVIDENCE OF HARM:
1. Long-term INTERMITTANT administration of a positive inotrope.
2. Use of an ARB instead of an ACE-I when the ACE-I can be tolerated.
3. Addition of and ARB instead of a BB in patients already taking an ACE-I.
4. Use of a CCB as a primary treatment for HF.
F. Non-Pharmacologic Therapies
1. Salt and water restriction.
2. Heart-healthy diet, especially one low in animal fats
3.
4.
5.
G. Pacing:
1.
IV.
Elimination of alcohol in cardiomyopathy; moderation in other conditions.
Aerobic exercise (mentioned above); cardiac rehabilitation where indicated.
Smoking cessation.
Biventricular pacing: approximately 20% of pts with HF have a wide QRS, usually due to LBBB leading
to dysynchronous contraction of the ventricles associated with worse prognosis. Biventricular pacing for
synchronicity has been shown to improve sxs of failure, and is indicated in patients with Stage C or D
disease, an EF less than 35%, and a QRS duration > 120 ms.
2. Cardioverter-Defibrillators: Malignant ventricular arrhythmias are common in HF, and most antiarrhythmic drugs are contraindicated in HF. Use of Amiodarone alone is controversial, therefore:
implantation of a cardioverter/defibrillator is indicated in patients with HF who have a history of VF or
hemodynamically destabilizing VT. The ACC/AHA currently recommend prophylactic placement in
patients with STAGE C disease with ischemic cardiomyopathy with an EF <= 30%. Note: this is NOT
indicated in STAGE D disease, due to the poor life-expectancy in this stage of disease (MADIT-II Trial).
H. Endovascular/Surgical Management:
1. PTCA/CABG (if viable/threatened myocardium or symptomatic or demonstrable ischemia).
2. Valve replacement/repair.
3. Ventricular remodeling after MI (removal of scar tissue/favorably reshaping the heart).
4. Ventricular assist device implantation.
5. Heart transplantation.
Treatment of Heart Failure with Preserved Systolic Function (Diastolic Dysfunction):
A. The best management strategies for these patients have not yet been defined.
B. Recommendations:
1. Control systolic and diastolic hypertension.
2. Control rate in AF and in treat arrhythmias.
3. Diuretic use as in systolic dysfunction, above.
4. Consider the use of ACE-I and BB as above.
5. Consider the use of Digoxin as above.
6. Symptomatic or demonstrable ischemia – consider coronary revascularization.