Congestive heart failure acute pharmacotherapy
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Synonyms and keywords: acute decompensated heart failure, ADHF, flash pulmonary edema
Overview
Acute heart failure can occur in the setting of a new onset heart failure or worsening of an existing chronic heart failure (also known as acute decompensated heart failure, flash pulmonary edema, ADHF). ADHF presents with acute shortness of breath due to the development of pulmonary edema (the rapid accumulation of fluid in the lung). Other signs and symptoms of ADHF include hypotension with impaired and organ perfusion manifested by worsening renal function, altered mentation and cold clammy extremities. ADHF associated with a poor prognosis if not treated aggressively. Like chronic heart failure therapy, the goal is to improve symptoms but unlike chronic therapy the other goals are to improve oxygenation and hemodynamic stability. The mainstays of the acute medical treatment in acute decompensated congestive heart failure include oxygen to improve hypoxia, diuresis to reduce both preload and intravascular volume and vasodilators to reduce afterload. Some of the mainstays of chronic heart failure therapy are not initiated acutely (ACE inhibtors,beta blockers and digoxin).
General Recommendations
Hospitalization
Hospitalization is required for the management of the patient with ADHF with the following signs, symptoms and laboratory abnormalities: [1]
- Hypotension and/or cardiogenic shock
- Evidence of poor end organ perfusion such as worsening renal function, cold clammy extremities, altered mental status
- Hypoxemia with an oxygen saturation under 90%
- Atrial fibrillation with a rapid ventricular response resulting in hypotension
- The possible presence of an acute coronary syndrome and ongoing myocardial ischemia
Telemetry and Monitoring
The patient should be admitted to a level of care that allows for constant electrocardiographic monitoring given the risk of arrhythmias and frequent vital signs.
- The heart rhythm and oxygen saturation should be monitored continuously.
- Is and Os (intake and output) should be monitored carefully. A daily target should be established (for example the patient should be one liter negative for the day) and diuretic dosing should be adjusted to achieve this target.
- Daily weights should be obtained using the same scale at the same time of the day, usually before the patient has eaten, and after they have first voided in the morning. Often times Is and Os measurements will underestimate insensible losses that occur through the lungs.
- The BUN and creatinine, serum sodium(to detect hyponatremia which carries a poor prognosis), chloride, bicarbonate (to detect contraction alkalosis) and serum potassium (to detect hypokalemia as a result of diuresis and which can precipitate arrhythmias) should be monitored daily. Potassium and magnesium should be repeated as needed following diuresis.
Medical Therapy
Systolic Versus Diastolic Heart Failure
The management of the patient with acute decompensated heart failure depends upon whether the patient has acute decompensated systolic heart failure or acute decompensated diastolic heart failure. Both forms of acute decompensated heart failure are treated with oxygen and vasodilator therapy and diuresis. Importantly, inotropic agents that increase contractility are not indicated in the patient with acute decompensated diastolic heart failure while they are important for the patient with acute decompensated systolic heart failure. While beta blocker initiation is relatively contraindicated in acute decompensated systolic heart failure, control of tachycardia is very useful in the patient with diastolic heart failure to prolong left ventricular filling time. While the initiation of ACE inhibitors may not be recommended in acute decompensated systolic heart failure, ACE inhibition may be of benefit in acute decompensated diastolic heart failure.
Treatment Goals
- Reduce preload
- Reduce afterload
- Reduce intravascular volume
- Improve cardiac contractility
Management Plan
Oxygen
- Oxygen improves the patient's status if hypoxemia is present. Continuous positive airway pressure may be applied using a face mask; this has been shown to improve symptoms more quickly than oxygen therapy alone,[2] and has been shown to reduce the risk of death.[3][4] Severe respiratory failure requires treatment with endotracheal intubation and mechanical ventilation.
Diuretics
- Diuretics reduce preload and reduce intravascular volume. Intravenous diuretics are often required in the acute setting. If high doses of furosemide are inadequate, boluses or continuous infusions of bumetanide may be preferred. These loop diuretics may be combined with thiazide diuretics such as oral metolazone or intravenous chlorthiazide for a synergistic effect. Intravenous preparations are preferred because of more predictable absorption. When a patient is extremely fluid overloaded, they can develop intestinal edema as well, which can affect enteral absorption of medications.
Nitroglycerine
- Nitroglycerine reduces afterload and reduces preload. Nitroglycerine is helpful in improving symptoms of dyspnea.
Morphine
- Morphine reduces preload, reduces catecholamines, and reduces the stimulation by stretch receptors in the lung thereby improving symptoms of dyspnea.
More Aggressive Pharmacotherapy
- Nitroprusside reduces afterload and reduces preload
- Ionotropes may be administered if the patient's circulatory volume is adequate but there is persistent evidence of inadequate end-organ perfusion.
- Milrinone increases contractility and reduces afterload
- Dobutamine increases contractility in reduces afterload
- Dopamine increases blood pressure and increases renal perfusion at low doses
- Nesiritide reduces afterload and reduces preload and can be used if other therapies have not been effective.
Arrhythmias
Atrial Fibrillation
Atrial fibrillation can cause acute decompensation of heart failure due to an increase in heart rate and oxygen demands, and conversely acute decompensation of heart failure can precipitate atrial fibrillation due to left atrial dilation and increased wall stress. Thus, atrial fibrillation and acute decompensated heart failure are often intimately related, and the successful management of atrial fibrillation is often critical to the success of reversing the acute decompensation.
In the patient with acute decompensated heart failure, rate control of atrial fibrillation is the mainstay of arrhythmia therapy. Obviously agents that have a negative inotropic effect such as beta blockers and non-dihydropyridine calcium channel blockers are relatively contraindicated in the management of acute decompensated systolic heart failure. Intravenous diltiazem does not have a negative inotropic effect and is often used for rate control. Short acting esmolol is sometimes used. Digoxin has a very narrow therapeutic/toxic window, it's onset of action is relatively delayed, and it is often not used.
If a patient is in cardiogenic shock, then cardioversion can be considered in the patient with atrial fibrillation, however in the absence of severe hemodynamic compromise it should be noted that atrial fibrillation will often recur in this setting. Thus, cardioversion is not particularly helpful in the absence of profound hemodynamic compromise. If the patient is going to be cardioverted, unfractionated heparin should be administered.
References
- ↑ Lindenfeld J, Albert NM, Boehmer JP, Collins SP, Ezekowitz JA, Givertz MM, Katz SD, Klapholz M, Moser DK, Rogers JG, Starling RC, Stevenson WG, Tang WH, Teerlink JR, Walsh MN (2010). "HFSA 2010 Comprehensive Heart Failure Practice Guideline". Journal of Cardiac Failure. 16 (6): e1–194. doi:10.1016/j.cardfail.2010.04.004. PMID 20610207. Retrieved 2013-04-29. Unknown parameter
|month=ignored (help) - ↑ Gray A, Goodacre S, Newby DE, Masson M, Sampson F, Nicholl J (2008). "Noninvasive ventilation in acute cardiogenic pulmonary edema". N. Engl. J. Med. 359 (2): 142–51. doi:10.1056/NEJMoa0707992. PMID 18614781. Unknown parameter
|month=ignored (help) - ↑ Peter JV, Moran JL, Phillips-Hughes J, Graham P, Bersten AD (2006). "Effect of non-invasive positive pressure ventilation (NIPPV) on mortality in patients with acute cardiogenic pulmonary oedema: a meta-analysis". Lancet. 367 (9517): 1155–63. doi:10.1016/S0140-6736(06)68506-1. PMID 16616558. Unknown parameter
|month=ignored (help) - ↑ Weng CL; Zhao YT; Liu QH; et al. (2010). "Meta-analysis: Noninvasive ventilation in acute cardiogenic pulmonary edema". Ann. Intern. Med. 152 (9): 590–600. doi:10.1059/0003-4819-152-9-201005040-00009. PMID 20439577. Unknown parameter
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