Download Management of Congestive Heart Failure: Review Questions

Self -Assessment in Cardiology
Management of Congestive Heart Failure:
Review Questions
Lekshmi Dharmarajan, MD, FACP, FACC
QUESTIONS
Choose the single best answer for each question.
1. Which of the following statements regarding congestive heart failure (CHF) is correct?
A) Neurohormones do not play a role in cardiac
remodeling or progression of CHF
B) The most common etiology of CHF today is
hypertensive heart disease
C) The most useful diagnostic test for evaluating
CHF is 2-D echocardiography with Doppler
flow studies
D) The New York Heart Association classification
for heart failure correlates with ejection fraction
E) The presence of dyspnea helps differentiate
diastolic from systolic dysfunction
2.
3.
Which of the following statements about the pharmacologic management of CHF is INCORRECT?
A) Administration of diuretics is the only reliable
means to control fluid retention in CHF
B) Angiotensin-converting enzyme (ACE)
inhibitors exert favorable effects on cardiac
remodeling
C) Combining hydralazine and nitrate is an alternative therapy for patients who cannot tolerate ACE inhibitors
D) Digoxin significantly improves survival of
patients with CHF
E) Positive inotropic agents are not recommended
for intravenous infusion in an outpatient setting
Which of the following statements does NOT correctly describe the role of β-blockers in CHF resulting from systolic dysfunction?
A) β-blockers block the action of catecholamines,
which are deleterious to the myocardium
B) β-blockers improve ejection fraction in CHF
C) β-blockers may enhance coronary blood flow
D) Long-term use of β-blockers risks worsening
of CHF
E) Use of β-blockers decreases hospitalizations
and improves patient survival
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4.
A 60-year-old man with idiopathic dilated cardiomyopathy is admitted to the intensive care unit with
dyspnea. Medications include an ACE inhibitor,
digoxin, and furosemide. Physical examination
reveals a blood pressure of 100/60 mm Hg, engorged jugular veins, bilateral rales, an S3, and
pedal edema. Chest radiography confirms pulmonary edema. The ejection fraction is 25% (low) on
an echocardiogram. The patient improves with intravenous furosemide, as well as restriction of salt
and fluid intake. Which of the following statements
about the patient’s drug therapy is correct?
A) Carvedilol therapy should have been initiated
at the time of admission
B) He should continue on the same regimen
C) He should receive carvedilol once he is stable
(preferably as an outpatient)
D) The blood pressure of 100/60 mm Hg is a
contraindication to use of carvedilol
E) The low ejection fraction is a contraindication
to use of carvedilol
5.
Which of the following statements regarding diuretic resistance in CHF is INCORRECT?
A) Administration of slow-infusion loop diuretics
helps overcome diuretic resistance
B) Combining thiazide with a loop diuretic
increases its efficacy
C) Rapid, repeated intravenous administration of
loop diuretics is safe
D) Use of nonsteroidal anti-inflammatory drugs
may contribute to diuretic resistance
E) Worsening renal function requires administration of higher doses of diuretics
(turn page for answers)
Dr. Dharmarajan is a Clinical Associate Professor of Medicine, Weill
Medical College of Cornell University, New York, NY; and Chief,
Division of Cardiology, and Director, Coronary Care Unit, Lincoln
Medical and Mental Health Center, Bronx, NY.
Hospital Physician July 2001
39
Self -Assessment in Cardiology : pp. 39 – 40
EXPLANATION OF ANSWERS
1. (C) The most useful diagnostic test for evaluating
CHF is 2-D echocardiography with Doppler flow
studies. Echocardiography with Doppler study in
patients with CHF helps to determine if the primary
abnormality is pericardial, myocardial, or valvular
and measures left ventricular ejection fraction to differentiate systolic from diastolic dysfunction. Neurohormones play a major role in the remodeling and
progression of heart failure; they include norepinephrine, renin-angiotensin-aldosterone system, atrial natriuretic peptide, endothelin, antidiuretic hormone, interleukin-6, and tumor necrosis factor α.
The most common cause of CHF today is coronary
artery disease, accounting for two thirds of cases. The
New York Heart Association classification is a functional status classification based on symptoms and
does not correlate with ejection fraction. Although
dyspnea is most commonly a symptom in systolic dysfunction, dyspnea from acute pulmonary edema can
be a feature of diastolic dysfunction; thus, presentation alone does not help to differentiate the two.
2. (D) Digoxin significantly improves survival of patients with CHF. Digoxin improves symptoms, quality
of life, and functional capacity in patients with mild
to moderate CHF, regardless of underlying rhythm,
but it does not improve patient survival. Although
diuretic use is the only means of enabling salt and
water excretion in patients with CHF, these drugs
should always be used in conjunction with other
agents, usually angiotensin-converting enzyme
(ACE) inhibitors and β-blockers. ACE inhibitors are
useful in managing left ventricular systolic dysfunction with or without symptoms of CHF; they favorably affect remodeling and survival. The benefits
from a hydralazine-nitrate combination may result
from biochemical, antioxidant, and/or vasodilatory
effects. However, the 2 drugs are not first-line treatments prior to the use of ACE inhibitors. Because of
the risk of death and lack of efficacy data, intravenous infusion of positive inotropic agents is not
recommended for outpatients.
3. (D) Long-term use of β-blockers risks worsening of
CHF. Although the negative inotropic effect of
β -blockers was initially considered a risk in heart
failure, these drugs actually improve ejection fraction in CHF. Although short-term deterioration
may occur, continued therapy improves symptoms.
Catecholamines cause vasoconstriction, increase
metabolic demands, decrease diastolic filling, reduce coronary flow, and affect left ventricular remodeling; therefore, blocking chronic adrenergic
stimulation is beneficial. The use of β-blockers such
as carvedilol and metoprolol results in improved
ejection fraction (noticeable within a few months),
fewer hospitalizations, and improved survival.
4. (C) He should receive carvedilol once he is stable
(preferably as an outpatient). Carvedilol is a nonselective β-blocker with additional peripheral vasodilating properties (through α-blockade) and is
approved for use in patients with CHF. Carvedilol
therapy should not be initiated at the time of hospital admission, when the patient is decompensated;
rather, the optimum time is when the patient is stable, following adequate diuresis. Treatment is begun
with small doses of carvedilol, typically 3.125 mg
twice daily, and gradually titrated upward to a maximum dose of 25 mg twice daily. The systolic blood
pressure of 100 mm Hg and the low ejection fraction are not contraindications to carvedilol therapy;
both should improve with therapy.
5. (C) Rapid, repeated intravenous administration of
loop diuretics is safe. Large, rapid, intravenous doses
of loop diuretics may be effective but incur the risk of
ototoxicity and should not be administered repeatedly. Constant intravenous infusion of loop diuretics is
effective and prevents resistance from postdiuretic
tubular reabsorption of sodium. Several causes contribute to diuretic resistance in CHF, including dietary
noncompliance with salt restriction. Nonsteroidal
anti-inflammatory drugs cause salt and fluid retention
by inhibiting the formation of vasodilator prostaglandins, reducing renal blood flow, and decreasing
the glomerular filtration rate. Worsening renal function results in inadequate concentrations of diuretics
in the tubular lumen, necessitating intravenous therapy, larger doses of the drugs, or combination therapy
with a thiazide. Typically, the thiazide, which has a
longer half-life than a loop diuretic, is administered
30 to 60 minutes before the loop diuretic for synergy.
SUGGESTED READINGS
Consensus recommendations for the management of chronic heart failure. On behalf of the membership of the advisory
council to improve outcomes nationwide in heart failure.
Am J Cardiol 1999;83:1A–38A.
Gomberg-Maitland M, Baran DA, Fuster V. Treatment of congestive heart failure: guidelines for the primary care physician
and the heart failure specialist. Arch Intern Med 2001;161:
342–52.
Heart failure. In: Arky RA, Kettyle WM, Hatem CJ, editors.
MKSAP 12: Cardiovascular medicine. Philadelphia: American College of Physicians–American Society of Internal
Medicine; 2001:38–49.
Copyright 2001 by Turner White Communications Inc., Wayne, PA. All rights reserved.
40 Hospital Physician July 2001
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