Dilated cardiomyopathy resident survival guide: Difference between revisions
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==FIRE: Focused Initial Rapid Evaluation== | |||
A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients with signs and symptoms of severe acute decompensated heart failure who require immediate intervention.<ref name="pmid23741057">{{cite journal| author=Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH et al.| title=2013 ACCF/AHA guideline for the management of heart failure: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. | journal=Circulation | year= 2013 | volume= 128 | issue= 16 | pages= 1810-52 | pmid=23741057 | doi=10.1161/CIR.0b013e31829e8807 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23741057 }} </ref><br> | |||
<span style="font-size:85%">Boxes in red signify that an urgent management is needed.</span> | |||
<span style="font-size:85%">'''Abbreviations:''' | |||
'''BU:''' [[Blood urea nitrogen]]; | |||
'''COPD:''' [[Chronic obstructive pulmonary disease]]; | |||
'''D5W:''' 5% dextrose solution in water ; | |||
'''HF:''' [[Heart failure]]; | |||
'''IV:''' [[Intravenous]]; | |||
'''MAP:''' [[Mean arterial pressure]]; | |||
'''Na:''' [[Sodium]]; | |||
'''NSAID:''' [[Non steroidal anti-inflammatory drug]]; | |||
'''SBP:''' [[Systolic blood pressure]]; | |||
'''S3:''' [[Third heart sound]]; | |||
</span> | |||
<br> | |||
{{familytree/start}} | |||
{{familytree | | | A01 | | A01=<div style="float: left; text-align: left; width: 35em; padding:1em;"> '''Identify cardinal findings that increase the pretest probability of acute decompensated heart failure'''<br> | |||
❑ [[Dyspnea]]<br> | |||
❑ [[Cool extremities]]<br> | |||
❑ [[Pedal edema|Peripheral edema]] <br> | |||
❑ [[Decreased urine output]] <br> | |||
❑ Past medical history of [[heart failure]] <br> | |||
❑ History of [[orthopnea]] and [[paroxysmal nocturnal dyspnea]]<br> | |||
❑ Pulmonary [[crepitations]]/[[rales]]/[[crackles]]<br> | |||
❑ [[Heart sounds#Third heart sound S3|Third heart sound (S3)]]</div>}} | |||
{{familytree | | | |!| |}} | |||
{{familytree | | | W01 | |W01=<div style="float: left; text-align: left; width: 35em; padding:1em;">'''Does the patient have any of the following findings that require hospitalization and urgent management?'''<br> | |||
❑ Severe decompendated HF: | |||
:❑ [[Hypotension]] (either [[SBP]] < 90 mmHg or drop in [[MAP]] >30 mmHg) and/or [[cardiogenic shock]]<br> | |||
:❑ [[Altered mental status]]<br> | |||
:❑ [[Cool extremities|Cold and clammy extremities]]<br> | |||
:❑ [[Oliguria|Urine output <0.5mL/kg/hr]]<br> | |||
❑ [[Dyspnea]] at rest manifested by [[tachypnea]] or oxygen saturation <90% <br> | |||
❑ [[Atrial fibrillation|<span style="color:white;">Atrial fibrillation</span>]] with a rapid ventricular response resulting in [[hypotension]] | |||
❑ [[Acute coronary syndrome]] </div> | |||
:❑ '''[[Chest pain|<span style="color:white;"> Chest pain</span>]] or [[chest discomfort|<span style="color:white;">chest discomfort</span>]]''' <br> | |||
::❑ Sudden onset | |||
::❑ Sensation of heaviness, tightness, pressure, or squeezing | |||
::❑ Duration> 20 minutes <br> | |||
::❑ Radiation to the left arm, jaw, neck, right arm, back or [[epigastrium|<span style="color:white;">epigastrium</span>]] | |||
::❑ No relief with medications<br> | |||
::❑ No relief with rest <br> | |||
::❑ Worse with time <br> | |||
::❑ Worse with exertion<br> | |||
:❑ [[Palpitations]] | |||
:❑ [[Nausea]] | |||
:❑ [[Vomiting]] | |||
:❑ [[Sweating]]</div>}} | |||
{{familytree | |,|-|^|-|.| |}} | |||
{{familytree | B01 | | B02 | |B01=<div style=" background: #FA8072"> {{fontcolor|#F8F8FF|Yes}}</div> |B02='''No'''}} | |||
{{familytree | |!| | | |!| | |}} | |||
{{familytree | C01 | | C02 | |C01=<div style=" background: #FA8072"> {{fontcolor|#F8F8FF|Admit to a level of care that allows for constant ECG monitoring}}</div> | |||
|C02=<div style="float: left; text-align: center; width: 25em;">[[Heart failure resident survival guide#Complete Diagnostic Approach|Proceed to complete diagnostic approach]]</div> }} | |||
{{familytree | |!| | | | | | |}} | |||
{{familytree |boxstyle=background: #FA8072; color: #F8F8FF; | D01 | | | | | |D01= <div style="float: left; text-align: left; width: 45em; padding:1em;"> | |||
'''Initial stabilization:''' <br> | |||
❑ Assess the airway <br> | |||
❑ Position the patient upright at an angle of 45 degrees, with legs dangling off the bedside (decrease [[preload|<span style="color:white;">preload</span>]])<br> | |||
❑ Monitor [[heart rate|<span style="color:white;">heart failure</span>]] and [[blood pressure|<span style="color:white;">blood pressure</span>]] continuously<br> | |||
❑ Monitor oxygen saturation continuously<br> | |||
❑ If [[hypoxemia|<span style="color:white;">hypoxemia</span>]] is present (Sa02 < 90% or Pa02 <60 mmHg), administer oxygen with/without [[noninvasive ventilation|<span style="color:white;">noninvasive ventilation</span>]] <br> | |||
❑ Consider administration of [[Morphine|<span style="color:white;">morphine</span>]] IV to reduce symptom severity.<br> | |||
:❑ Initial dose 4-8 mg | |||
:❑ 2-8 mg every 5 to 15 minutes, as needed | |||
❑ Secure intravenous access with 18 gauge cannula <br> | |||
❑ Monitor fluid intake and urine output carefully to guide diuretic dose titration) <br><br> | |||
'''Assess congestion and perfusion:'''<br> | |||
'''''Congestion at rest''''' (dry vs. wet)<br> | |||
''"Wet" suggested by orthopnea, ↑JVP, rales, S3, pedal edema''<br> | |||
'''''Low perfusion at rest (warm vs. cold)'''''<br> | |||
''"Cold" suggested by narrow [[pulse pressure|<span style="color:white;">pulse pressure</span>]], [[cool extremities|<span style="color:white;">cool extremities</span>]], [[hypotension|<span style="color:white;">hypotension</span>]]'' <br> | |||
The patient is:<br> | |||
❑ Warm and dry, OR <br> | |||
❑ Warm and wet, OR <br> | |||
❑ Cold and dry, OR <br> | |||
❑ Cold and wet <br><br> | |||
'''Identify precipitating factor and treat accordingly:''' <br> | |||
''Click on the precipitating factor for more details on the management'' <br> | |||
❑ [[Acute coronary syndrome|<span style="color:white;">Acute coronary syndrome</span>]] <br> | |||
❑ [[Myocarditis|<span style="color:white;">Myocarditis</span>]] <br> | |||
❑ [[Renal failure|<span style="color:white;">Renal failure</span>]] <br> | |||
❑ [[Hypertensive crisis|<span style="color:white;">Hypertensive crisis</span>]] <br> | |||
❑ Non adherence to medications <br> | |||
❑ Worsening [[aortic stenosis|<span style="color:white;">Aortic stenosis</span>]] <br> | |||
❑ Drugs ([[NSAIDS|<span style="color:white;">NSAIDS</span>]], [[thiazides|<span style="color:white;">thiazides</span>]], [[calcium channel blocker|<span style="color:white;">calcium channel blocker</span>]], [[beta blockers|<span style="color:white;">beta blockers</span>]]) <br> | |||
❑ Toxins ([[alcohol|<span style="color:white;">alcohol</span>]], [[anthracycline|<span style="color:white;">anthracyclines</span>]]) <br> | |||
❑ [[Atrial fibrillation|<span style="color:white;">Atrial fibrillation</span>]] <br> | |||
: ''Rate control of [[atrial fibrillation|<span style="color:white;">atrial fibrillation</span>]] is the mainstay of [[arrhythmia|<span style="color:white;">arrhythmia</span>]] therapy. Avoid the use of drugs with negative [[inotropic|<span style="color:white;">inotropic</span>]] effects such as [[beta blocker|<span style="color:white;">beta blockers</span>]] and [[non-dihydropyridine calcium channel blocker|<span style="color:white;">non-dihydropyridine calcium channel blockers</span>]] e.g., [[verapamil|<span style="color:white;">verapamil</span>]] in the treatment of acute decompensated [[systolic heart failure|<span style="color:white;">systolic heart failure</span>]]'' | |||
: ''Consider [[cardioversion|<span style="color:white;">cardioversion</span>]] if the patient is in [[cardiogenic shock|<span style="color:white;">cardiogenic shock</span>]] or if new onset [[atrial fibrillation|<span style="color:white;">atrial fibrillation</span>]] is the clear precipitant of the hemodynamic decompensation'' | |||
❑ [[COPD|<span style="color:white;">COPD</span>]] <br> | |||
❑ [[Pulmonary embolism|<span style="color:white;">Pulmonary embolism</span>]] <br> | |||
❑ [[Anemia|<span style="color:white;">Anemia</span>]] <br> | |||
❑ [[Thyroid|<span style="color:white;">Thyroid</span>]] abnormalities <br> | |||
❑ Systemic [[infection|<span style="color:white;">infection</span>]] <br><br> | |||
'''Treat congestion and optimize volume status:''' <br> | |||
'''''Diuretics''''' <br> | |||
❑ Administer IV [[loop diuretics|<span style="color:white;">loop diuretics</span>]] as intermittent boluses or continuous infusion (I-B)<br> | |||
:❑ If patient is already on [[loop diuretics|<span style="color:white;">loop diuretics</span>]]: Rule of thumb: Administer IV dose with total daily dose = 2.5 x usual daily PO dose<br> | |||
:❑ Generally, administer IV furosemide bolus dose 40 mg IV for patients with normal renal function. | |||
:❑ If patient is not already on [[loop diuretics|<span style="color:white;">loop diuretics</span>]], administer IV starting dose: | |||
:: [[Furosemide|<span style="color:white;">Furosemide</span>]] 20 to 40 mg (most common), '''OR''' | |||
:: [[Torsemide|<span style="color:white;">Torsemide</span>]] 5 to 10 mg, '''OR''' | |||
:: [[Bumetanide|<span style="color:white;">Bumetanide</span>]] 0.5 to 1 mg | |||
:❑ Evaluate adequacy of diuresis. For furosemide, adequate diuresis is defined as urine output > 1L/2hours following IV administration. | |||
:❑ If not adequate, increase furosemide IV dose to 80 mg. Re-evaluate diuresis adequacy in the following 2 hours post-administration. | |||
:❑ Titrate dose until adequate diuresis is achieved. Once achieved, administer the dose at a twice daily rate. | |||
:❑ Perform serial assessment of fluid input and output, [[vital signs|<span style="color:white;">vital signs</span>]], daily body weight (measured every day, with the same scale, at the same time, after first void) and symptoms <br> | |||
:❑ Order daily [[electrolytes|<span style="color:white;">electrolytes</span>]], [[BUN|<span style="color:white;">BUN</span>]], [[creatinine|<span style="color:white;">creatinine</span>]] (I-C) <br> | |||
❑ Low sodium diet (<2 g daily)<br><br> | |||
❑ In case of persistent symptoms: | |||
:❑ Add a second [[diuretics|<span style="color:white;">diuretics</span>]], such as [[thiazide|<span style="color:white;">thiazide</span>]] (preferably metolazone) (I-B) <br> | |||
:❑ Metolazone PO dose: 2.5 - 10 mg once daily (there is no IV preparation for metolazone) | |||
:❑ Reassess diuresis adequacy several hours (2 to 9) following metolazone administration. | |||
❑ Consider low dose [[dopamine|<span style="color:white;">dopamine</span>]] infusion for improved diuresis and renal blood flow (IIb-B) <br> | |||
❑ Consider [[renal replacement therapy|<span style="color:white;">renal replacement therapy</span>]]/[[ultrafiltration|<span style="color:white;">ultrafiltration</span>]] in obvious volume overload (IIb-B) refractory to higher dose/combination of IV diuretics <br> | |||
❑ Maintenance of diuresis | |||
:❑ Consider continuous infusion of furosemide following bolus administration | |||
'''''Venodilators'''''<br> | |||
❑ Consider IV [[nitroglycerin|<span style="color:white;">nitroglycerin</span>]], [[nitroprusside|<span style="color:white;">nitroprusside</span>]], or [[nesiritide|<span style="color:white;">nesiritide</span>]] as add-on to diuretics to relieve [[dyspnea|<span style="color:white;">dyspnes</span>]] (IIb-A) <br><br> | |||
:''Do not administer [[vasodilator|<span style="color:white;">vesodilators</span>]] among patients with [[hypotension|<span style="color:white;">hypotension</span>]].'' | |||
'''Treat low perfusion:'''<br> | |||
❑ [[Inotrope|<span style="color:white;">Inotropes</span>]] (click her for details)<br><br> | |||
:''If the patient is total body and intravascular volume overloaded in normotensive, then [[diuresis|<span style="color:white;">diuresis</span>]] alone should be undertaken. If the patient is volume overloaded but [[hypotensive|<span style="color:white;">hypotensive</span>]], then [[inotrope|<span style="color:white;">inotropes</span>]] must be administered in addition to [[diuretics|<span style="color:white;">diuretics</span>]].'' | |||
'''Invasive hemodynamic monitoring:'''<br><br> | |||
❑ Consider [[Right heart catheterization|<span style="color:white;">Pulmonary artery catheterization</span>]] in case of failure to respond to medical therapy, [[respiratory distress|<span style="color:white;">respiratory distress</span>]], [[shock|<span style="color:white;">shock</span>]], uncertainty regarding volume status, or increase in [[creatinine|<span style="color:white;">creatinine</span>]]; assess the following parameters:<br> | |||
:❑ [[PCWP|<span style="color:white;">PCWP</span>]] | |||
:❑ [[Cardiac output|<span style="color:white;">Cardiac output</span>]] | |||
:❑ [[Systemic vascular resistance|<span style="color:white;">Systemic vascular resistance</span>]] | |||
'''VTE prevention:''' <br> | |||
❑ [[Anticoagulation|<span style="color:white;">Anticoagulation</span>]] in the absence of contraindications (I-B)<br><br> | |||
'''Chronic medical therapy:''' <br> | |||
❑ Chronic [[ACE inhibitor|<span style="color:white;">ACE inhibitor</span>]]: Hold if patient is hemodynamically unstable <br> | |||
❑ Chronic [[beta blocker|<span style="color:white;">beta blocker</span>]]: | |||
: Hold if patient is hemodynamically unstable and/or in need or [[inotrope|<span style="color:white;">inotropes</span>]] | |||
: Decrease dose by ≥ half if patient is in moderate [[heart failure|<span style="color:white;">heart failure</span>]] | |||
❑ DO NOT INITIATE ACE INHIBITORS during an acute decompensation<br> | |||
❑ DO NOT INITIATE BETA BLOCKER during an acute decompensation; initiate beat blockers at a low dose in stable patients following optimization of volume status and D/C IV diuretics and inotropes (I-B) <br><br> | |||
'''Monitor laboratory tests:''' <br> | |||
❑ [[BUN|<span style="color:white;">BUN</span>]] <br> | |||
❑ [[Creatinine|<span style="color:white;">Creatinine</span>]] <br> | |||
❑ [[Sodium|<span style="color:white;">Sodium</span>]] (to detect [[hyponatremia|<span style="color:white;">hyponatremia</span>]] which carries a poor prognosis), [[chloride|<span style="color:white;">chloride</span>]], [[bicarbonate|<span style="color:white;">bicarbonate</span>]] (to detect [[contraction alkalosis|<span style="color:white;">contraction alkalosis</span>]]) and serum potassium (to detect [[hypokalemia|<span style="color:white;">hypokalemia</span>]] as a result of diuresis and which can precipitate [[arrhythmia|<span style="color:white;">arrhythmias</span>]]), [[potassium|<span style="color:white;">potassium</span>]], [[magnesium|<span style="color:white;">magnesium</span>]] <br> | |||
'''Management of hyponatremia:''' <br> | |||
❑ Water restriction <br> | |||
:❑ <2 L/day if Na is < 130 meq/L | |||
:❑ < 1 L/day or more if the Na is < 125 meq/L </div>}} | |||
{{familytree/end}} | |||
==Complete Diagnostic Approach== | ==Complete Diagnostic Approach== |
Revision as of 18:08, 19 May 2015
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Steven Bellm, M.D. [2]
Dilated cardiomyopathy resident survival guide Microchapters |
---|
Overview |
Causes |
Diagnosis |
Do's |
Dont's |
Overview
Dilated cardiomyopathy (DCM) relates to a group of heterogeneous myocardial disorders and is characterized by dilatation and impaired contraction and systolic function of the left or both ventricles. Atrial and/or ventricular arrhythmias can occcur, and there is a risk for sudden death. [1] The weight of the heart assessed by the MRI and echocardiogram is increased but the maximal thicknesses of the left ventricular free wall and septum are usually normal as a result of the abnormally dilated chambers.[2] Dilated cardiomyopathy is treated the same way that congestive heart failure is.
Causes
Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.[3]
- Life-threatening causes:
- Common causes:
- Idiopathic
- Myocarditis
- Ischemic heart disease
- Infiltrative disease
- Peripartum cardiomyopathy
- Hypertension
- Human immunodeficiency virus (HIV) infection
- Connective tissue disease
- Substance abuse
- Doxorubicin
- Other
FIRE: Focused Initial Rapid Evaluation
A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients with signs and symptoms of severe acute decompensated heart failure who require immediate intervention.[4]
Boxes in red signify that an urgent management is needed.
Abbreviations:
BU: Blood urea nitrogen;
COPD: Chronic obstructive pulmonary disease;
D5W: 5% dextrose solution in water ;
HF: Heart failure;
IV: Intravenous;
MAP: Mean arterial pressure;
Na: Sodium;
NSAID: Non steroidal anti-inflammatory drug;
SBP: Systolic blood pressure;
S3: Third heart sound;
Identify cardinal findings that increase the pretest probability of acute decompensated heart failure ❑ Dyspnea | |||||||||||||||||
Does the patient have any of the following findings that require hospitalization and urgent management?
❑ Severe decompendated HF:
❑ Dyspnea at rest manifested by tachypnea or oxygen saturation <90%
| |||||||||||||||||
Yes | No | ||||||||||||||||
Admit to a level of care that allows for constant ECG monitoring | |||||||||||||||||
Initial stabilization:
❑ Secure intravenous access with 18 gauge cannula Assess congestion and perfusion: Identify precipitating factor and treat accordingly:
❑ COPD Treat congestion and optimize volume status:
❑ Low sodium diet (<2 g daily)
❑ Consider low dose dopamine infusion for improved diuresis and renal blood flow (IIb-B)
Venodilators
Treat low perfusion:
Invasive hemodynamic monitoring: VTE prevention: Chronic medical therapy:
❑ DO NOT INITIATE ACE INHIBITORS during an acute decompensation Monitor laboratory tests: Management of hyponatremia:
| |||||||||||||||||
Complete Diagnostic Approach
A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.[5]
Symptoms of heart failure | |||||||||||||||||||||||||||||||||||||||||||||
History and symptoms: ❑ Hints for etiology (at least 3 generations of family history, and others) | |||||||||||||||||||||||||||||||||||||||||||||
Physical examination: ❑ Vital signs:
❑ General appearance:
❑ Heart:
❑ Lungs:
❑ Abdomen:
❑ Extremities:
| |||||||||||||||||||||||||||||||||||||||||||||
Laboratory findings: ❑ Complete blood count
| |||||||||||||||||||||||||||||||||||||||||||||
Imaging and additional tests: ❑ Noninvasive imaging:
❑ Invasive imaging: Consider invasive Imaging only in specific cases.
| |||||||||||||||||||||||||||||||||||||||||||||
Examples for specific findings for dilated cardiomyopathy:
❑ Echo (dilated left and/or right ventricle, global hypokinesis with left ventricular ejection fraction under 40% | |||||||||||||||||||||||||||||||||||||||||||||
Rapidly progressive symptoms (within 1 month)? And/or new ventricular tachycardia? | |||||||||||||||||||||||||||||||||||||||||||||
Yes | No | ||||||||||||||||||||||||||||||||||||||||||||
Consider endomyocardial biopsy | Treat with conventional heart failure medications | ||||||||||||||||||||||||||||||||||||||||||||
Clinical improvement after 1 week? | |||||||||||||||||||||||||||||||||||||||||||||
Yes | No | ||||||||||||||||||||||||||||||||||||||||||||
Continue conventional heart failure treatment | Consider endomyocardial biopsy | ||||||||||||||||||||||||||||||||||||||||||||
Do's
- The initial diagnostic approach should aim to identify potentially reversible causes of left ventricular dysfunction. Pertinent history includes alcohol consumption, recent viral illness, coronary risk factors, and family history.
Dont's
- Endomyocardial biopsy should not be performed in the routine evaluation of patients with HF.[5] Optimal timing of endomyocardial biopsy for patients unresponsive to medical therapy remains unclear.[3]
- Nondihydropyridine calcium channel blockers with negative inotropic effects may be harmful in asymptomatic patients with low LVEF and no symptoms of HF after MI.[6]
References
- ↑ "Report of the WHO/ISFC task force on the definition and classification of cardiomyopathies". Br Heart J. 44 (6): 672–3. 1980. PMC 482464. PMID 7459150.
- ↑ Tazelaar HD, Billingham ME (1986). "Leukocytic infiltrates in idiopathic dilated cardiomyopathy. A source of confusion with active myocarditis". Am J Surg Pathol. 10 (6): 405–12. PMID 3521345.
- ↑ 3.0 3.1 Felker GM, Thompson RE, Hare JM, Hruban RH, Clemetson DE, Howard DL; et al. (2000). "Underlying causes and long-term survival in patients with initially unexplained cardiomyopathy". N Engl J Med. 342 (15): 1077–84. doi:10.1056/NEJM200004133421502. PMID 10760308.
- ↑ Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): 1810–52. doi:10.1161/CIR.0b013e31829e8807. PMID 23741057.
- ↑ 5.0 5.1 Yancy, C. W.; Jessup, M.; Bozkurt, B.; Butler, J.; Casey, D. E.; Drazner, M. H.; Fonarow, G. C.; Geraci, S. A.; Horwich, T.; Januzzi, J. L.; Johnson, M. R.; Kasper, E. K.; Levy, W. C.; Masoudi, F. A.; McBride, P. E.; McMurray, J. J. V.; Mitchell, J. E.; Peterson, P. N.; Riegel, B.; Sam, F.; Stevenson, L. W.; Tang, W. H. W.; Tsai, E. J.; Wilkoff, B. L. (2013). "2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines". Circulation. 128 (16): e240–e327. doi:10.1161/CIR.0b013e31829e8776. ISSN 0009-7322.
- ↑ WRITING COMMITTEE MEMBERS. Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): e240–327. doi:10.1161/CIR.0b013e31829e8776. PMID 23741058.