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[[Congestive heart failure]] and [[cardiac dysfunction]] are not interchangeable definitions. Whereas heart failure is a clinical definition that illustrates the occurrence of symptoms of fatigue, dyspnea, and fluid overload; cardiac dysfunction is a mechanical definition that includes abnormalities in heart contraction (called [[systolic dysfunction]]) or abnormalities in heart relaxation and filling (called [[diastolic dysfunction]]) or both.
[[Congestive heart failure]] and [[cardiac dysfunction]] are not interchangeable definitions. Whereas heart failure is a clinical definition that illustrates the occurrence of symptoms of fatigue, dyspnea, and fluid overload; cardiac dysfunction is a mechanical definition that includes abnormalities in heart contraction (called [[systolic dysfunction]]) or abnormalities in heart relaxation and filling (called [[diastolic dysfunction]]) or both.


Therefore, '''diastolic dysfunction''' refers to a mechanical dysfunction of the heart during the diastolic phase of the [[cardiac cycle]] in the presence or absence of any clinical symptoms. When clinical symptoms are present on top of the mechanical dysfunction of the heart, the condition is called '''diastolic heart failure'''<ref name="pmid11901053">{{cite journal| author=Zile MR, Brutsaert DL| title=New concepts in diastolic dysfunction and diastolic heart failure: Part I: diagnosis, prognosis, and measurements of diastolic function. | journal=Circulation | year= 2002 | volume= 105 | issue= 11 | pages= 1387-93 | pmid=11901053 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11901053  }} </ref>.
Therefore, diastolic dysfunction refers to a mechanical dysfunction of the heart during the diastolic phase of the [[cardiac cycle]] in the presence or absence of any clinical symptoms. When clinical symptoms are present on top of the mechanical dysfunction of the heart, the condition is called diastolic heart failure<ref name="pmid11901053">{{cite journal| author=Zile MR, Brutsaert DL| title=New concepts in diastolic dysfunction and diastolic heart failure: Part I: diagnosis, prognosis, and measurements of diastolic function. | journal=Circulation | year= 2002 | volume= 105 | issue= 11 | pages= 1387-93 | pmid=11901053 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11901053  }} </ref>.


[[Diastole]] is the phase of the [[cardiac cycle]] when the heart ( i.e. [[ventricle]]) is not contracting but is actually relaxed and filling with blood that is being returned to it, either from the body (into [[right ventricle]]) or from the lungs ( into [[left ventricle]]). The mechanical abnormality in diastolic dysfunction is characterized by a decrease in the ventricular filling in the context of an elevated left ventricular end diastolic pressure and a normal ejection fraction.
[[Diastole]] is the phase of the [[cardiac cycle]] when the heart ( i.e. [[ventricle]]) is not contracting but is actually relaxed and filling with blood that is being returned to it, either from the body (into [[right ventricle]]) or from the lungs ( into [[left ventricle]]). The mechanical abnormality in diastolic dysfunction is characterized by a decrease in the ventricular filling in the context of an elevated left ventricular end diastolic pressure and a normal ejection fraction.Diastolic dysfunction is caused by decrease cardiac muscle relaxation or increased stiffness. The [[ejection fraction]] of the heart is preserved in this type of dysfunction.Systolic and diastolic dysfunction commonly occur in conjunction with each other.


Diastolic dysfunction is caused by decrease cardiac muscle relaxation or increased stiffness. The [[ejection fraction]] of the heart is preserved in this type of dysfunction.
==Classification==
 
There are four basic echocardiographic patterns of diastolic heart failure, which are graded I to IV. Grade I is called an "abnormal relaxation pattern", grade II is called "pseudonormal filling dynamics", grade III is called "restrictive filling dynamics", and grade IV is called "reversible restrictive diastolic dysfunction".
Systolic and diastolic dysfunction commonly occur in conjunction with each other.


==Pathophysiology==
==Pathophysiology==
Diastolic dysfunction is the impairment of the heart muscle in its ability to properly relax and fill with blood during [[diastole]]. Diastolic dysfunction is mainly the result of either impaired myocardial relaxation or increased cardiac muscle stiffness. As a result, the pressure in the left [[ventricle]] increases at the end of diastole and causes a build up of pressure in the left [[atrium]] and consequently in the pulmonary circulation. The result is [[pulmonary edema]] and [[dyspnea]].
Diastolic dysfunction is the impairment of the heart muscle in its ability to properly relax and fill with blood during [[diastole]]. Diastolic dysfunction is mainly the result of either impaired myocardial relaxation or increased cardiac muscle stiffness. As a result, the pressure in the left [[ventricle]] increases at the end of diastole and causes a build up of pressure in the left [[atrium]] and consequently in the pulmonary circulation. The result is [[pulmonary edema]] and [[dyspnea]].
Normally, with reference to the left side of the heart, blood flows from the lungs, into the [[pulmonary veins]], into the [[left atrium]], through the [[mitral valve]], and finally into the [[left ventricle]].
Diastolic dysfunction is the inability of the heart to properly relax and fill with blood during diastole.
===Underlying Causes of [[Diastolic Dysfunction]]===
====Impaired extent and/or speed of myocardial relaxation====
*Myocardial relaxation is an ATP dependent process regulated by the rate of re-uptake of cytoplasmic calcium into the sarcoplasmic reticulum.
*Low concentration of calcium, as seen in [[ischemia]], is associated with a slowed down myocardial relaxation.
====Increased myocardial stiffness====
*Myocardial stiffness can be secondary to cardiac muscle hypertrophy (for example as seen in [[hypertension]]). Concentric hypertrophy (increased mass and relative wall thickness) and remodelling (normal mass but increased wall thickness) are associated with diastolic dysfunction due to impaired filling.
*Myocardial stiffness can be the result of [[infiltrative diseases]] like [[amyloidosis]].
*Scarred heart muscle, occurring after a heart attack, are relatively stiff.
*[[Diabetes]] can be a cause of cardiac stiffness as a result of [[glycosylation]] of the heart muscle.
====Extrinsic constraints====
*Extrinsic constraints can be seen in pericardial compression.
====Chamber dilatation====
*Severe systolic dysfunction that has led to ventricular dilation can be associated with diastolic dysfunction. When the ventricle has been stretched to a certain point, any further attempt to stretch it more, as by blood trying to enter it from the left atrium, meets with increased resistance and thus decreased compliance.
====Miscelleneous====
*In [[mitral stenosis]], blood cannot readily flow out from the [[left atrium]] into the [[left ventricle]] since the valve between those two heart chambers is blocked which causes the blood to back up into the left atrium and, eventually, the lungs. [[Pulmonary edema]] may result.
*Diastolic dysunction secondary to [[mitral stenosis]] is especially seen when the heart rate is elevated, as occurs in [[exercise]] and [[pregnancy]]. Thus, there will be insufficient time for the blood to traverse the narrowed passageway (i.e. [[mitral valve]]) between the [[left atrium]] and [[left ventricle]].<ref>Mann D.L., Chakinala M. (2012). Chapter 234. Heart Failure and Cor Pulmonale. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.</ref>
===Sequence of Events in [[Diastolic Dysfunction]]===
*Impaired cardiac muscle relaxation or/and decreased left ventricular compliance lead to delay in left ventricular filling.
*Left ventricular end diastolic pressure will become high.
*Pulmonary capillary pressure increases.<ref>Mann D.L., Chakinala M. (2012). Chapter 234. Heart Failure and Cor Pulmonale. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.</ref>
**As a result of hydrostatic forces, this high pressure leads to leaking of fluid (i.e. [[transudate]]) from the lung's blood vessels into the air-spaces ([[alveoli]]) of the lungs. The result is [[pulmonary edema]], a condition characterized by difficulty breathing, inadequate [[oxygenation]] of blood, and, if severe and untreated, death. Life threatening episodes of pulmonary edema can occur due to sudden decompensation. This is called ''flash pulmonary edema''. The left ventricle diastolic pressure rises progressively prior to the acute onset failure<ref name="pmid18794390">{{cite journal| author=Zile MR, Bennett TD, St John Sutton M, Cho YK, Adamson PB, Aaron MF et al.| title=Transition from chronic compensated to acute decompensated heart failure: pathophysiological insights obtained from continuous monitoring of intracardiac pressures. | journal=Circulation | year= 2008 | volume= 118 | issue= 14 | pages= 1433-41 | pmid=18794390 | doi=10.1161/CIRCULATIONAHA.108.783910 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=18794390  }} </ref><ref name="pmid21440865">{{cite journal| author=Zile MR, Adamson PB, Cho YK, Bennett TD, Bourge RC, Aaron MF et al.| title=Hemodynamic factors associated with acute decompensated heart failure: part 1--insights into pathophysiology. | journal=J Card Fail | year= 2011 | volume= 17 | issue= 4 | pages= 282-91 | pmid=21440865 | doi=10.1016/j.cardfail.2011.01.010 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21440865  }} </ref><ref name="pmid21549292">{{cite journal| author=Adamson PB, Zile MR, Cho YK, Bennett TD, Bourge RC, Aaron MF et al.| title=Hemodynamic factors associated with acute decompensated heart failure: part 2--use in automated detection. | journal=J Card Fail | year= 2011 | volume= 17 | issue= 5 | pages= 366-73 | pmid=21549292 | doi=10.1016/j.cardfail.2011.01.011 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21549292  }} </ref>.
*It is worth re-emphasizing that the [[pulmonary edema]] that can develop as a result of [[diastolic dysfunction]] is ''not'' due to poor pumping function of the left [[ventricle]]. Indeed, it has resulted from the left ventricle's inability to readily accept blood trying to enter it from the left [[atrium]].
*In the setting of a stiff left ventricle, it is more difficult for blood to flow into it from the [[left atrium]]. In such a situation, filling can be maintained by a combination of coordinated left atrial pumping (i.e. beating) and a relatively slow [[heart rate]]. The former actively pumps blood into the stiff left ventricle, and the latter can allow for sufficient time for blood to passively enter the left ventricle from the left atrium.
*Conditions that increase the heart rate, for example [[exercise]] and [[pregnancy,]] decrease the diastolic filling time and hence worsens the diastolic dysfunction in the setting of a non-compliant heart.


==Causes==
==Causes==
In alphabetical order:
[[Diastolic dysfunction]] is the mechanical abnormality of the heart to properly relax and fill with blood during [[diastole]]. Several medical conditions may cause this to occur; namely cardiovascular conditions, genetic conditions, pulmonary conditions, rheumatologic conditions, and [[diabetes]].
*[[Amyloidosis]]
*[[Aortic stenosis]]
*[[Constrictive pericarditis]]
*[[Diabetes]]
*[[Effusive-constrictive pericarditis]]
*[[Glycogen storage disease]]
*[[Hemochromatosis]]
*[[Hypereosinophilic syndrome]]
*[[Hypertrophic heart diseases]](for example, as seen in [[hypertension]])
*[[Hypertrophic obstructive cardiomyopathy]] ([[HOCM]])
*[[Infiltrative diseases]] ( for example, [[amyloidosis]])
*[[Ischemia]]
*[[Mitral stenosis]]
*[[Myocardial infarction]] and scar
*[[Pericardial effusion]]
*[[Restrictive cardiomyopathy]]
*[[Sarcoidosis]]
*[[Systolic dysfunction]]


==Differentiation of [[Diastolic Dysfunction]] from [[Systolic Dysfunction]]==
==Differentiating Diastolic dysfunction from other Diseases==
*'''Characteristics of systolic dysfunction:'''
Diastolic heart failure is one of the examples of heart failure with preserved [[ejection fraction]]. Other causes that cause heart failure and do not affect ejection fraction need to be differentiated from this condition.
**Large, dilated, eccentrically hypertrophied ventricles
==Epidemiology and Demographics==
**Impaired blood ejection during [[systole]]
About half of patients with heart failure have a normal ejection fraction<ref name="pmid17090767">{{cite journal| author=Bursi F, Weston SA, Redfield MM, Jacobsen SJ, Pakhomov S, Nkomo VT et al.| title=Systolic and diastolic heart failure in the community. | journal=JAMA | year= 2006 | volume= 296 | issue= 18 | pages= 2209-16 | pmid=17090767 | doi=10.1001/jama.296.18.2209 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17090767  }} </ref>. The prevalence of diastolic dysfunction has increased, although mortality rates have stayed the same. Diastolic dysfunction is more common in females than in males, and more common in the elderly.
**Decreased [[cardiac output]] and [[ejection fraction]]
**Normal or decreased [[blood pressure]]
**Can occur in any age and more frequent in men than in women
**Presence of [[S3 gallop]]
*'''Characteristics of diastolic dysfunction:'''
**Small, thickened, concentrically hypertrophied ventricles
**Large atria
**Impaired blood filling during [[diastole]]
**Normal ejection fraction
**Systemic elevation of the [[blood pressure]]
**Occurs mainly in elderly women
**Presence of [[S4 gallop]] <ref>Francis G.S., Tang W., Walsh R.A. (2011). Chapter 26. Pathophysiology of Heart Failure. In V. Fuster, R.A. Walsh, R.A. Harrington (Eds), Hurst's The Heart, 13e.</ref>


==Differentiation of Diastolic Dysfunction from other Disorders==
==Natural History, Complications and Prognosis==
*[[Right heart failure]]
[[Heart failure]] associated with [[diastolic dysfunction]] has a slightly better prognosis than that of systolic [[heart failure]]. However, the presence or absence of [[coronary artery disease]], the age, and the left ventricular [[ejection fraction]] cut off level must all be taken into consideration in stratifying patients and assessing their prognosis.<ref name="pmid1860957">{{cite journal| author=Terek RM, Wehner J, Lubicky JP| title=Crankshaft phenomenon in congenital scoliosis: a preliminary report. | journal=J Pediatr Orthop | year= 1991 | volume= 11 | issue= 4 | pages= 527-32 | pmid=1860957 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1860957  }} </ref>
*[[Valvular heart disease]]
*[[Pericardial disease]]s - [[constrictive pericarditis]], [[cardiac tamponade]]
*[[Cardiac tumors]]
*[[High output cardiac failure]]


==Diagnosis==
===Diagnostic Criteria===
The evaluation of the presence of [[diastolic dysfunction]] in patients presenting with symptoms of [[heart failure]] is of paramount importance. The diagnosis of diastolic dysfunction or diastolic heart failure is not clinical and requires a work up that goes beyond the history, physical exam, [[echocardiography]] and chest X-rays. Several studies have evaluated the diagnostic criteria to follow in differentiating [[systolic dysfunction]] from [[diastolic dysfunction]].


==Epidemiology and Demographics==
===History and Symptoms===
The prevalence of diastolic dysfunction has increased and it is more common in females and the elderly.
The classic symptoms of heart failure include [[dyspnea]], [[fatigue]], and [[fluid retention]]. Patients with diastolic heart failure may present in different ways. Some patients present with [[exercise intolerance]] but show little evidence of [[congestion]] or [[edema]]. Other patients present with mild symptoms of [[edema]] and [[pulmonary congestion]].


==Prognosis==
===Physical Examination===
Until recently, it was generally assumed that the prognosis for individuals with diastolic dysfunction and associated, intermittent pulmonary edema was better than those with systolic dysfunction. In fact, in two studies appearing in the [[New England Journal of Medicine]] in 2006, evidence was presented to suggest that the prognosis in diastolic dysfunction is the same as that in systolic dysfunction<ref name="pmid16855265">{{cite journal| author=Owan TE, Hodge DO, Herges RM, Jacobsen SJ, Roger VL, Redfield MM| title=Trends in prevalence and outcome of heart failure with preserved ejection fraction. | journal=N Engl J Med | year= 2006 | volume= 355 | issue= 3 | pages= 251-9 | pmid=16855265 | doi=10.1056/NEJMoa052256 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=16855265 }} </ref><ref name="pmid16855266">{{cite journal| author=Bhatia RS, Tu JV, Lee DS, Austin PC, Fang J, Haouzi A et al.| title=Outcome of heart failure with preserved ejection fraction in a population-based study. | journal=N Engl J Med | year= 2006 | volume= 355 | issue= 3 | pages= 260-9 | pmid=16855266 | doi=10.1056/NEJMoa051530 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=16855266  }}  [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17213179 Review in: Evid Based Med. 2006 Dec;11(6):185] [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17080990 Review in: ACP J Club. 2006 Nov-Dec;145(3):78] </ref>
In general, signs of both [[left sided heart failure]] and [[right sided heart failure]] are present. Signs that represent acute left sided failure include cool clammy skin, [[cyanosis]], [[rales]] and a [[gallop rhythm]]Signs that represent right sided failure include an elevated [[JVP]], [[pedal edema]], [[ascites]], [[hepatomegaly]], a [[parasternal heave]] and [[hepatojugular reflux]].


==Laboratory Findings==
===Laboratory Findings===
Plasma [[brain natriuretic peptide]] ([[BNP]]) or [[N-terminal pro b-type natriuretic peptide]] ([[NT-proBNP]]) can be used to diagnose heart failure when diagnosis is unclear.  [[BNP]] levels are lower in diastolic dysfunction when compared with systolic dysfunction<ref name="pmid12798574">{{cite journal| author=Maisel AS, McCord J, Nowak RM, Hollander JE, Wu AH, Duc P et al.| title=Bedside B-Type natriuretic peptide in the emergency diagnosis of heart failure with reduced or preserved ejection fraction. Results from the Breathing Not Properly Multinational Study. | journal=J Am Coll Cardiol | year= 2003 | volume= 41 | issue= 11 | pages= 2010-7 | pmid=12798574 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=12798574  }} </ref>.
The initial laboratory tests in diastolic dysfunction or failure include [[complete blood count]], [[urinalysis]], [[Electrolytes|serum electrolytes]], [[blood urea nitrogen]], [[serum creatinine]], fasting blood glucose ([[glycohemoglobin]]), [[lipid]] profile, [[liver function tests]], and [[thyroid-stimulating hormone]]. The measurement of BNP is done only when diagnosis is unclear.


==Echocardiography==
===Echocardiography===
Echocardiography can be used to diagnose diastolic dysfunction. No one single echocardiographic parameter can confirm a diagnosis of diastolic heart failure. Multiple echocardiographic parameters have been proposed as sufficiently sensitive and specific, including mitral inflow velocity patterns, pulmonary vein flow patterns, E:A reversal, tissue Doppler measurements, and M-mode echo measurements (i.e. of left atrial size). Algorithms have also been developed which combine multiple echocardiographic parameters to diagnose diastolic heart failure.
Diastolic dysfunction, in the presence or absence of [[diastolic heart failure]], is a challenging diagnosis that has several diagnostic approaches. While [[cardiac catheterization]] can be used to establish the diagnosis of diastolic dysfunction by the invasive measurement of elevated left ventricular end diastolic pressure and mean pulmonary capillary pressure, [[echocardiography]] provides an alternative noninvasive diagnostic tool.
===Other Diagnostic Studies===
Cardiac catheterization can be used to measure the [[PCWP]] and the [[LVEDP]]. These are important predictors of the filling pressure and the degree of myocardial disease progression in dilated cardiomyopathy.


==Treatment==
==Treatment==
===Medical Therapy===
The chronic treatment of diastolic dysfunction involves aggressive management of the underlying disorder that is causing the diastolic dysfunction such as [[diabetes]] or [[hypertension]].  Mild diastolic dysfunction that is well tolerated requires no specific treatment.  Rate control is an important part of the acute therapy of the patient with diastolic heart failure.  It takes a longer period of time for a stiff left ventricle to fill, and therefore rate control is a critical part of the acute therapy of diastolic dysfunction.
The chronic treatment of diastolic dysfunction involves aggressive management of the underlying disorder that is causing the diastolic dysfunction such as [[diabetes]] or [[hypertension]].  Mild diastolic dysfunction that is well tolerated requires no specific treatment.  Rate control is an important part of the acute therapy of the patient with diastolic heart failure.  It takes a longer period of time for a stiff left ventricle to fill, and therefore rate control is a critical part of the acute therapy of diastolic dysfunction.
==Acute Treatment of Diastolic Heart Failure==
=== Rate Control===
It takes a longer period of time for a stiff left ventricle to fill, and therefore rate control is a critical part of the acute therapy diastolic dysfunction.  Furthermore, in [[atrial fibrillation]] there is a failure of [[atrial kick]] to augment the filling of the [[left ventricle]].
=== Diuresis===
Diuresis may reduce acute volume overload.
=== Relief of Ischemia===
Acute [[myocardial ischemia]] leads to diastolic dysfunction which increases left atrial pressure and causes [[pulmonary edema]].
== Chronic Treatment of Diastolic Heart Failure==
=== Afterload Reduction===
There is some evidence that [[calcium channel blocker]] drugs may be of benefit in reducing ventricular stiffness in some cases.  Likewise, treatment with [[angiotensin converting enzyme inhibitors]] such as [[enalapril]], [[ramipril]], and other ACE inhibitors may be of benefit due to their effect on [[ventricular remodeling]].
==Medical Therapy==
==ACA/AHA 2009 Guidelines for the Diagnosis and Management of Heart Failure in Adults: Patients With Heart Failure and Normal Left Ventricular Ejection Fraction<ref name="pmid19324966">{{cite journal| author=Hunt SA, Abraham WT, Chin MH, Feldman AM, Francis GS, Ganiats TG et al.| title=2009 focused update incorporated into the ACC/AHA 2005 Guidelines for the Diagnosis and Management of Heart Failure in Adults: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines: developed in collaboration with the International Society for Heart and Lung Transplantation. | journal=Circulation | year= 2009 | volume= 119 | issue= 14 | pages= e391-479 | pmid=19324966 | doi=10.1161/CIRCULATIONAHA.109.192065 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19324966  }} </ref> (DO NOT EDIT)==
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LightGreen"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class I]]
|-
| bgcolor="LightGreen"|
<nowiki>"</nowiki>'''1.''' Physicians should control systolic and diastolic [[hypertension]] in patients with [[heart failure]] and normal left ventricular [[ejection fraction]], in accordance with published guidelines. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|-
| bgcolor="LightGreen"|
<nowiki>"</nowiki>'''2.''' Physicians should control ventricular rate in patients with heart failure and normal left ventricular ejection fraction and [[atrial fibrillation]]. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|-
| bgcolor="LightGreen"|
<nowiki>"</nowiki>'''3.''' Physicians should use diuretics to control pulmonary congestion and peripheral edema in patients with heart failure and normal left ventricular ejection fraction. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|}
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LemonChiffon"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class IIa]]
|-
|bgcolor="LemonChiffon"|
<nowiki>"</nowiki>'''1.''' Coronary [[revascularization]] is reasonable in patients with heart failure and normal left ventricular ejection fraction and [[coronary artery disease]] in whom symptomatic or demonstrable [[myocardial ischemia]] is judged to be having an adverse effect on cardiac function. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|}
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LemonChiffon"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class IIb]]
|-
|bgcolor="LemonChiffon"|
<nowiki>"</nowiki>'''1.''' Restoration and maintenance of sinus rhythm in patients with atrial fibrillation and heart failure and normal left ventricular ejection fraction might be useful to improve symptoms. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|-
|bgcolor="LemonChiffon"|
<nowiki>"</nowiki>'''2.''' The use of [[beta-adrenergic]] blocking agents, [[ACEI]]s, ARBs, or calcium antagonists in patients with heart failure and normal left ventricular ejection fraction and controlled hypertension might be effective to minimize symptoms of heart failure. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|-
|bgcolor="LemonChiffon"|
<nowiki>"</nowiki>'''3.''' The usefulness of [[digitalis]] to minimize symptoms of heart failure in patients with heart failure and normal left ventricular ejection fraction is not well established. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|}


==References==
==References==
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Latest revision as of 14:37, 14 January 2018

Diastolic dysfunction Microchapters

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Assistant Editor(s)-in-Chief: Rim Halaby

Overview

Congestive heart failure and cardiac dysfunction are not interchangeable definitions. Whereas heart failure is a clinical definition that illustrates the occurrence of symptoms of fatigue, dyspnea, and fluid overload; cardiac dysfunction is a mechanical definition that includes abnormalities in heart contraction (called systolic dysfunction) or abnormalities in heart relaxation and filling (called diastolic dysfunction) or both.

Therefore, diastolic dysfunction refers to a mechanical dysfunction of the heart during the diastolic phase of the cardiac cycle in the presence or absence of any clinical symptoms. When clinical symptoms are present on top of the mechanical dysfunction of the heart, the condition is called diastolic heart failure[1].

Diastole is the phase of the cardiac cycle when the heart ( i.e. ventricle) is not contracting but is actually relaxed and filling with blood that is being returned to it, either from the body (into right ventricle) or from the lungs ( into left ventricle). The mechanical abnormality in diastolic dysfunction is characterized by a decrease in the ventricular filling in the context of an elevated left ventricular end diastolic pressure and a normal ejection fraction.Diastolic dysfunction is caused by decrease cardiac muscle relaxation or increased stiffness. The ejection fraction of the heart is preserved in this type of dysfunction.Systolic and diastolic dysfunction commonly occur in conjunction with each other.

Classification

There are four basic echocardiographic patterns of diastolic heart failure, which are graded I to IV. Grade I is called an "abnormal relaxation pattern", grade II is called "pseudonormal filling dynamics", grade III is called "restrictive filling dynamics", and grade IV is called "reversible restrictive diastolic dysfunction".

Pathophysiology

Diastolic dysfunction is the impairment of the heart muscle in its ability to properly relax and fill with blood during diastole. Diastolic dysfunction is mainly the result of either impaired myocardial relaxation or increased cardiac muscle stiffness. As a result, the pressure in the left ventricle increases at the end of diastole and causes a build up of pressure in the left atrium and consequently in the pulmonary circulation. The result is pulmonary edema and dyspnea.

Causes

Diastolic dysfunction is the mechanical abnormality of the heart to properly relax and fill with blood during diastole. Several medical conditions may cause this to occur; namely cardiovascular conditions, genetic conditions, pulmonary conditions, rheumatologic conditions, and diabetes.

Differentiating Diastolic dysfunction from other Diseases

Diastolic heart failure is one of the examples of heart failure with preserved ejection fraction. Other causes that cause heart failure and do not affect ejection fraction need to be differentiated from this condition.

Epidemiology and Demographics

About half of patients with heart failure have a normal ejection fraction[2]. The prevalence of diastolic dysfunction has increased, although mortality rates have stayed the same. Diastolic dysfunction is more common in females than in males, and more common in the elderly.

Natural History, Complications and Prognosis

Heart failure associated with diastolic dysfunction has a slightly better prognosis than that of systolic heart failure. However, the presence or absence of coronary artery disease, the age, and the left ventricular ejection fraction cut off level must all be taken into consideration in stratifying patients and assessing their prognosis.[3]

Diagnosis

Diagnostic Criteria

The evaluation of the presence of diastolic dysfunction in patients presenting with symptoms of heart failure is of paramount importance. The diagnosis of diastolic dysfunction or diastolic heart failure is not clinical and requires a work up that goes beyond the history, physical exam, echocardiography and chest X-rays. Several studies have evaluated the diagnostic criteria to follow in differentiating systolic dysfunction from diastolic dysfunction.

History and Symptoms

The classic symptoms of heart failure include dyspnea, fatigue, and fluid retention. Patients with diastolic heart failure may present in different ways. Some patients present with exercise intolerance but show little evidence of congestion or edema. Other patients present with mild symptoms of edema and pulmonary congestion.

Physical Examination

In general, signs of both left sided heart failure and right sided heart failure are present. Signs that represent acute left sided failure include cool clammy skin, cyanosis, rales and a gallop rhythm. Signs that represent right sided failure include an elevated JVP, pedal edema, ascites, hepatomegaly, a parasternal heave and hepatojugular reflux.

Laboratory Findings

The initial laboratory tests in diastolic dysfunction or failure include complete blood count, urinalysis, serum electrolytes, blood urea nitrogen, serum creatinine, fasting blood glucose (glycohemoglobin), lipid profile, liver function tests, and thyroid-stimulating hormone. The measurement of BNP is done only when diagnosis is unclear.

Echocardiography

Diastolic dysfunction, in the presence or absence of diastolic heart failure, is a challenging diagnosis that has several diagnostic approaches. While cardiac catheterization can be used to establish the diagnosis of diastolic dysfunction by the invasive measurement of elevated left ventricular end diastolic pressure and mean pulmonary capillary pressure, echocardiography provides an alternative noninvasive diagnostic tool.

Other Diagnostic Studies

Cardiac catheterization can be used to measure the PCWP and the LVEDP. These are important predictors of the filling pressure and the degree of myocardial disease progression in dilated cardiomyopathy.

Treatment

Medical Therapy

The chronic treatment of diastolic dysfunction involves aggressive management of the underlying disorder that is causing the diastolic dysfunction such as diabetes or hypertension. Mild diastolic dysfunction that is well tolerated requires no specific treatment. Rate control is an important part of the acute therapy of the patient with diastolic heart failure. It takes a longer period of time for a stiff left ventricle to fill, and therefore rate control is a critical part of the acute therapy of diastolic dysfunction.

References

  1. Zile MR, Brutsaert DL (2002). "New concepts in diastolic dysfunction and diastolic heart failure: Part I: diagnosis, prognosis, and measurements of diastolic function". Circulation. 105 (11): 1387–93. PMID 11901053.
  2. Bursi F, Weston SA, Redfield MM, Jacobsen SJ, Pakhomov S, Nkomo VT; et al. (2006). "Systolic and diastolic heart failure in the community". JAMA. 296 (18): 2209–16. doi:10.1001/jama.296.18.2209. PMID 17090767.
  3. Terek RM, Wehner J, Lubicky JP (1991). "Crankshaft phenomenon in congenital scoliosis: a preliminary report". J Pediatr Orthop. 11 (4): 527–32. PMID 1860957.

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