Right ventricular outflow tract obstruction pulmonary subvalvular stenosis: Difference between revisions
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== Anatomy == | == Anatomy == | ||
*There is hypertrophy of the infundibular muscle causing obstruction. | *There is hypertrophy of the infundibular muscle causing obstruction. <ref name="pmid17519398">{{cite journal| author=Pierpont ME, Basson CT, Benson DW, Gelb BD, Giglia TM, Goldmuntz E et al.| title=Genetic basis for congenital heart defects: current knowledge: a scientific statement from the American Heart Association Congenital Cardiac Defects Committee, Council on Cardiovascular Disease in the Young: endorsed by the American Academy of Pediatrics. | journal=Circulation | year= 2007 | volume= 115 | issue= 23 | pages= 3015-38 | pmid=17519398 | doi=10.1161/CIRCULATIONAHA.106.183056 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17519398 }} </ref> | ||
*The isolated form is rare, more commonly develops in response to an underlying [[VSD]]. | *The isolated form is rare, more commonly develops in response to an underlying [[VSD]]. <ref name="pmid10">{{cite journal |vauthors=Schmoldt A, Benthe HF, Haberland G, Raffle A, Gray J, MacDonald HR, Ehrhart IC, Parker PE, Weidner WJ, Dabney JM, Scott JB, Haddy FJ, Gatzy JT |title=Digitoxin metabolism by rat liver microsomes |journal=Biochem. Pharmacol. |volume=24 |issue=17 |pages=1639–41 |date=September 1975 |pmid=10 |pmc=5922622 |doi=10.1136/bmj.1.6001.93-a |url=}}</ref> | ||
==Historical Perspective== | |||
*The [[pulmonary valve]] and its function of allowing blood to the [[lungs]] for nourishment was first described by [[Hippocrates]]. <ref name="pmid18628928">{{cite journal |vauthors=Roberts WC, Ko JM |title=Some observations on mitral and aortic valve disease |journal=Proc (Bayl Univ Med Cent) |volume=21 |issue=3 |pages=282–99 |date=July 2008 |pmid=18628928 |pmc=2446420 |doi=10.1080/08998280.2008.11928412 |url=}}</ref> | |||
*Erasistratus, mentioned the function of the [[pulmonary valve]] in the unidirectional flow. <ref name="pmid19065003">{{cite journal| author=Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP et al.| title=Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. | journal=Eur J Echocardiogr | year= 2009 | volume= 10 | issue= 1 | pages= 1-25 | pmid=19065003 | doi=10.1093/ejechocard/jen303 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19065003 }} </ref> | |||
*Galen described the membranes of the [[valves]] and named them as "semilunar". <ref name="pmid7720297">{{cite journal| author=Waller BF, Howard J, Fess S| title=Pathology of tricuspid valve stenosis and pure tricuspid regurgitation--Part I. | journal=Clin Cardiol | year= 1995 | volume= 18 | issue= 2 | pages= 97-102 | pmid=7720297 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=7720297 }} </ref> | |||
*Mondino de Luzzi designed the sketch of the [[pulmonary valves]] in the anatomical position for the first time. | |||
*Realdo Colombo described the [[pulmonary circulation]] for the first time. <ref name="pmid7681733">{{cite journal |vauthors=Pellikka PA, Tajik AJ, Khandheria BK, Seward JB, Callahan JA, Pitot HC, Kvols LK |title=Carcinoid heart disease. Clinical and echocardiographic spectrum in 74 patients |journal=Circulation |volume=87 |issue=4 |pages=1188–96 |date=April 1993 |pmid=7681733 |doi=10.1161/01.cir.87.4.1188 |url=}}</ref> | |||
*Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. <ref name="pmid24661289">{{cite journal |vauthors=Gur AK, Odabasi D, Kunt AG, Kunt AS |title=Isolated tricuspid valve repair for Libman-Sacks endocarditis |journal=Echocardiography |volume=31 |issue=6 |pages=E166–8 |date=July 2014 |pmid=24661289 |doi=10.1111/echo.12558 |url=}}</ref> | |||
*The first transcatheter aortic valve replacement procedure in the world was performed on 16 April 2002 in a 57-year-old inoperable patient with severe aortic stenosis. The procedure was done by the Interventional Cardiologist Professor Alain Cribier at the Charles Nicolle University Hospital in Rouen, France. <ref name="pmid21365261">{{cite journal |vauthors=Muraru D, Badano LP, Sarais C, Soldà E, Iliceto S |title=Evaluation of tricuspid valve morphology and function by transthoracic three-dimensional echocardiography |journal=Curr Cardiol Rep |volume=13 |issue=3 |pages=242–9 |date=June 2011 |pmid=21365261 |doi=10.1007/s11886-011-0176-3 |url=}}</ref> | |||
==Classification== | |||
===Based on the severity of the stenosis=== | |||
Severity of pulmonary stenosis is classified based on the estimated peak velocity and peak resting gradient calculated using modified [[Bernoulli equation|Bernoulli equatio]]<nowiki/>n. It is classified into:<ref name="pmid19130998">{{cite journal| author=Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP et al.| title=Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. | journal=J Am Soc Echocardiogr | year= 2009 | volume= 22 | issue= 1 | pages= 1-23; quiz 101-2 | pmid=19130998 | doi=10.1016/j.echo.2008.11.029 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19130998 }}</ref> | |||
*'''Mild:''' Peak velocity less than 3m/s and peak [[gradient]] is less than 36 mm Hg.<ref name="pmid19130998">{{cite journal| author=Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP et al.| title=Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. | journal=J Am Soc Echocardiogr | year= 2009 | volume= 22 | issue= 1 | pages= 1-23; quiz 101-2 | pmid=19130998 | doi=10.1016/j.echo.2008.11.029 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19130998 }}</ref> | |||
*'''Moderate:''' Peak velocity is 3 to 4m/s and peak [[gradient]] is 36 to 64mm Hg. | |||
*According to 2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease, stages of severe [[pulmonic stenosis]] are defined as follows: This form of aortic stenosis presents later in life, usually after the age of 75. <ref>Townsend CM, et al. Sabiston Textbook of Surgery. 18th ed. Saunders; 2008:1841-1844.</ref> | |||
{| class="wikitable" | |||
!Stage | |||
!Definition | |||
!Valve Anatomy | |||
!Valve Hemodynamics | |||
!Hemodynamic Consequences | |||
!Symptoms | |||
|- | |||
|C,D | |||
|Severe pulmonic stenosis | |||
| | |||
*Thickened, distorted, possibly calcified leaflets with systolic doming and/or reduced excursion | |||
*Other anatomic abnormalities may be present, such as narrowed RVOT. | |||
| | |||
*Vmax >4 m/s; peak instantaneous gradient >64 mm Hg | |||
| | |||
*[[Right ventricular hypertrophy]] | |||
*Possible RV, RA enlargement | |||
*Poststenotic enlargement of main [[pulmonary artery]] | |||
| | |||
*None or variable and dependent on severity of obstruction | |||
|} | |||
*According to 2014 AHA/ACC Guidelines for the Management of Patients With Valvular Heart Disease, progression of valvular heart disease (VHD) are defined as follows:<ref name="pmid246031922">{{cite journal |vauthors=Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP, Guyton RA, O'Gara PT, Ruiz CE, Skubas NJ, Sorajja P, Sundt TM, Thomas JD |title=2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines |journal=J. Am. Coll. Cardiol. |volume=63 |issue=22 |pages=2438–88 |year=2014 |pmid=24603192 |doi=10.1016/j.jacc.2014.02.537 |url=}}</ref> | |||
{| class="wikitable" | |||
!Stage | |||
!Definition | |||
!Description | |||
|- | |||
|A | |||
|At risk | |||
|Patients with risk factors for development of [[valvular heart disease]] | |||
|- | |||
|B | |||
|Progressive | |||
|Patients with progressive [[valvular heart disease]] (mild-to-moderate severity and asymptomatic) | |||
|- | |||
|C | |||
|Asymptomatic severe | |||
|Asymptomatic patients who have the criteria for severe [[valvular heart disease]]: | |||
*C1: Asymptomatic patients with severe [[VHD]] in whom the left or [[right ventricle]] remains compensated | |||
*C2: Asymptomatic patients with severe [[VHD]] with decompensation of the left or [[right ventricle]] | |||
|- | |||
|D | |||
|Symptomatic severe | |||
|Patients who have developed symptoms as a result of [[valvular heart disease]] | |||
|} | |||
==Pathophysiology== | |||
===Pathogenesis=== | |||
*Pulmonic valve stenosis with fused [[commisures]] affect the flexibility of the [[valve]] causing obstruction of the outflow tract. In patients with dysplastic valves, the [[cusps]] are not fused but they are rigid from intrinsic thickening resulting in the narrowing of the outflow tract. The valve problems develop 5 - 10 years after the rheumatic fever, a tiny nodule forms along the valve leaflets. The degree of leaflet thickening and [[calcification]] and the severity of chordal involvement are variable. Rheumatic fever is becoming rare in the United States, so mitral stenosis is also less common. <ref name="agabegi2nd-ch1">Chapter 1: Diseases of the Cardiovascular system > Section: Valvular Heart Disease in: {{cite book |author=Elizabeth D Agabegi; Agabegi, Steven S. |title=Step-Up to Medicine (Step-Up Series) |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year=2008 |pages= |isbn=0-7817-7153-6 |oclc= |doi= |accessdate=}}</ref> | |||
*These morphological changes affect the complete opening of the [[pulmonic valve]] during the [[ventricular systole]] causing elevated right ventricular systolic pressures and leading to right ventricular remodelling. <ref name="pmid25771982">{{cite journal| author=Borgdorff MA, Dickinson MG, Berger RM, Bartelds B| title=Right ventricular failure due to chronic pressure load: What have we learned in animal models since the NIH working group statement? | journal=Heart Fail Rev | year= 2015 | volume= 20 | issue= 4 | pages= 475-91 | pmid=25771982 | doi=10.1007/s10741-015-9479-6 | pmc=4463984 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=25771982 }}</ref> | |||
*The obstruction leads to increased pressure overload on the [[right ventricle]] as it has to push the blood against resistance. <ref name="pmid10">{{cite journal |vauthors=Schmoldt A, Benthe HF, Haberland G, Price J, Philipps GR, Chiemprasert T |title=Digitoxin metabolism by rat liver microsomes |journal=Biochem. Pharmacol. |volume=24 |issue=17 |pages=1639–41 |date=September 1975 |pmid=10 |pmc=5922622 |doi=10.1016/0009-8981(75)90259-4 |url=}}</ref> | |||
== Clinical Features == | == Clinical Features == | ||
*Similar to valvar pulmonic stenosis | *Similar to valvar pulmonic stenosis. <ref name="pmid10901521">{{cite journal| author=Nazari S, Carli F, Salvi S, Banfi C, Aluffi A, Mourad Z et al.| title=Patterns of systolic stress distribution on mitral valve anterior leaflet chordal apparatus. A structural mechanical theoretical analysis. | journal=J Cardiovasc Surg (Torino) | year= 2000 | volume= 41 | issue= 2 | pages= 193-202 | pmid=10901521 | doi= | pmc= | url= }} </ref> | ||
*Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. <ref name="pmid282850">{{cite journal |vauthors=Neilson GH, Galea EG, Hossack KF |title=Thromboembolic complications of mitral valve disease |journal=Aust N Z J Med |volume=8 |issue=4 |pages=372–6 |date=August 1978 |pmid=282850 |doi=10.1111/j.1445-5994.1978.tb04904.x |url=}}</ref> <ref name="Lugiano-2013">{{Cite journal | last1 = Lugiano | first1 = CA. | title = Aortic stenosis. | journal = JAAPA | volume = 26 | issue = 11 | pages = 46-7 | month = Nov | year = 2013 | doi = 10.1097/01.JAA.0000436518.69169.8e | PMID = 24153092 }}</ref> | |||
*No poststenotic dilation of the pulmonary artery in contrast to valvar pulmonic stenosis. | |||
* | *Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. <ref name="pmid19130998">{{cite journal| author=Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP et al.| title=Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. | journal=J Am Soc Echocardiogr | year= 2009 | volume= 22 | issue= 1 | pages= 1-23; quiz 101-2 | pmid=19130998 | doi=10.1016/j.echo.2008.11.029 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19130998 }}</ref> | ||
*Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. | |||
==References== | ==References== | ||
Latest revision as of 02:22, 28 April 2020
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Right ventricular outflow tract obstruction Microchapters |
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Classification |
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Differentiating Right ventricular outflow tract obstruction from other Diseases |
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Right ventricular outflow tract obstruction pulmonary subvalvular stenosis On the Web |
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Associate Editor-in-Chief: Keri Shafer, M.D. [3]
Anatomy
- There is hypertrophy of the infundibular muscle causing obstruction. [1]
Historical Perspective
- The pulmonary valve and its function of allowing blood to the lungs for nourishment was first described by Hippocrates. [3]
- Erasistratus, mentioned the function of the pulmonary valve in the unidirectional flow. [4]
- Galen described the membranes of the valves and named them as "semilunar". [5]
- Mondino de Luzzi designed the sketch of the pulmonary valves in the anatomical position for the first time.
- Realdo Colombo described the pulmonary circulation for the first time. [6]
- Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. [7]
- The first transcatheter aortic valve replacement procedure in the world was performed on 16 April 2002 in a 57-year-old inoperable patient with severe aortic stenosis. The procedure was done by the Interventional Cardiologist Professor Alain Cribier at the Charles Nicolle University Hospital in Rouen, France. [8]
Classification
Based on the severity of the stenosis
Severity of pulmonary stenosis is classified based on the estimated peak velocity and peak resting gradient calculated using modified Bernoulli equation. It is classified into:[9]
- Mild: Peak velocity less than 3m/s and peak gradient is less than 36 mm Hg.[9]
- Moderate: Peak velocity is 3 to 4m/s and peak gradient is 36 to 64mm Hg.
- According to 2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease, stages of severe pulmonic stenosis are defined as follows: This form of aortic stenosis presents later in life, usually after the age of 75. [10]
| Stage | Definition | Valve Anatomy | Valve Hemodynamics | Hemodynamic Consequences | Symptoms |
|---|---|---|---|---|---|
| C,D | Severe pulmonic stenosis |
|
|
|
|
- According to 2014 AHA/ACC Guidelines for the Management of Patients With Valvular Heart Disease, progression of valvular heart disease (VHD) are defined as follows:[11]
| Stage | Definition | Description |
|---|---|---|
| A | At risk | Patients with risk factors for development of valvular heart disease |
| B | Progressive | Patients with progressive valvular heart disease (mild-to-moderate severity and asymptomatic) |
| C | Asymptomatic severe | Asymptomatic patients who have the criteria for severe valvular heart disease:
|
| D | Symptomatic severe | Patients who have developed symptoms as a result of valvular heart disease |
Pathophysiology
Pathogenesis
- Pulmonic valve stenosis with fused commisures affect the flexibility of the valve causing obstruction of the outflow tract. In patients with dysplastic valves, the cusps are not fused but they are rigid from intrinsic thickening resulting in the narrowing of the outflow tract. The valve problems develop 5 - 10 years after the rheumatic fever, a tiny nodule forms along the valve leaflets. The degree of leaflet thickening and calcification and the severity of chordal involvement are variable. Rheumatic fever is becoming rare in the United States, so mitral stenosis is also less common. [12]
- These morphological changes affect the complete opening of the pulmonic valve during the ventricular systole causing elevated right ventricular systolic pressures and leading to right ventricular remodelling. [13]
- The obstruction leads to increased pressure overload on the right ventricle as it has to push the blood against resistance. [2]
Clinical Features
- Similar to valvar pulmonic stenosis. [14]
- Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. [15] [16]
- No poststenotic dilation of the pulmonary artery in contrast to valvar pulmonic stenosis.
- Aortic stenosis was probably first described by Lazare Riviere (1589-1655), a French physician in 1663. [9]
References
- ↑ Pierpont ME, Basson CT, Benson DW, Gelb BD, Giglia TM, Goldmuntz E; et al. (2007). "Genetic basis for congenital heart defects: current knowledge: a scientific statement from the American Heart Association Congenital Cardiac Defects Committee, Council on Cardiovascular Disease in the Young: endorsed by the American Academy of Pediatrics". Circulation. 115 (23): 3015–38. doi:10.1161/CIRCULATIONAHA.106.183056. PMID 17519398.
- ↑ 2.0 2.1 Schmoldt A, Benthe HF, Haberland G, Raffle A, Gray J, MacDonald HR, Ehrhart IC, Parker PE, Weidner WJ, Dabney JM, Scott JB, Haddy FJ, Gatzy JT (September 1975). "Digitoxin metabolism by rat liver microsomes". Biochem. Pharmacol. 24 (17): 1639–41. doi:10.1136/bmj.1.6001.93-a. PMC 5922622. PMID 10.
- ↑ Roberts WC, Ko JM (July 2008). "Some observations on mitral and aortic valve disease". Proc (Bayl Univ Med Cent). 21 (3): 282–99. doi:10.1080/08998280.2008.11928412. PMC 2446420. PMID 18628928.
- ↑ Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP; et al. (2009). "Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice". Eur J Echocardiogr. 10 (1): 1–25. doi:10.1093/ejechocard/jen303. PMID 19065003.
- ↑ Waller BF, Howard J, Fess S (1995). "Pathology of tricuspid valve stenosis and pure tricuspid regurgitation--Part I." Clin Cardiol. 18 (2): 97–102. PMID 7720297.
- ↑ Pellikka PA, Tajik AJ, Khandheria BK, Seward JB, Callahan JA, Pitot HC, Kvols LK (April 1993). "Carcinoid heart disease. Clinical and echocardiographic spectrum in 74 patients". Circulation. 87 (4): 1188–96. doi:10.1161/01.cir.87.4.1188. PMID 7681733.
- ↑ Gur AK, Odabasi D, Kunt AG, Kunt AS (July 2014). "Isolated tricuspid valve repair for Libman-Sacks endocarditis". Echocardiography. 31 (6): E166–8. doi:10.1111/echo.12558. PMID 24661289.
- ↑ Muraru D, Badano LP, Sarais C, Soldà E, Iliceto S (June 2011). "Evaluation of tricuspid valve morphology and function by transthoracic three-dimensional echocardiography". Curr Cardiol Rep. 13 (3): 242–9. doi:10.1007/s11886-011-0176-3. PMID 21365261.
- ↑ 9.0 9.1 9.2 Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP; et al. (2009). "Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice". J Am Soc Echocardiogr. 22 (1): 1–23, quiz 101-2. doi:10.1016/j.echo.2008.11.029. PMID 19130998.
- ↑ Townsend CM, et al. Sabiston Textbook of Surgery. 18th ed. Saunders; 2008:1841-1844.
- ↑ Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP, Guyton RA, O'Gara PT, Ruiz CE, Skubas NJ, Sorajja P, Sundt TM, Thomas JD (2014). "2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines". J. Am. Coll. Cardiol. 63 (22): 2438–88. doi:10.1016/j.jacc.2014.02.537. PMID 24603192.
- ↑ Chapter 1: Diseases of the Cardiovascular system > Section: Valvular Heart Disease in: Elizabeth D Agabegi; Agabegi, Steven S. (2008). Step-Up to Medicine (Step-Up Series). Hagerstwon, MD: Lippincott Williams & Wilkins. ISBN 0-7817-7153-6.
- ↑ Borgdorff MA, Dickinson MG, Berger RM, Bartelds B (2015). "Right ventricular failure due to chronic pressure load: What have we learned in animal models since the NIH working group statement?". Heart Fail Rev. 20 (4): 475–91. doi:10.1007/s10741-015-9479-6. PMC 4463984. PMID 25771982.
- ↑ Nazari S, Carli F, Salvi S, Banfi C, Aluffi A, Mourad Z; et al. (2000). "Patterns of systolic stress distribution on mitral valve anterior leaflet chordal apparatus. A structural mechanical theoretical analysis". J Cardiovasc Surg (Torino). 41 (2): 193–202. PMID 10901521.
- ↑ Neilson GH, Galea EG, Hossack KF (August 1978). "Thromboembolic complications of mitral valve disease". Aust N Z J Med. 8 (4): 372–6. doi:10.1111/j.1445-5994.1978.tb04904.x. PMID 282850.
- ↑ Lugiano, CA. (2013). "Aortic stenosis". JAAPA. 26 (11): 46–7. doi:10.1097/01.JAA.0000436518.69169.8e. PMID 24153092. Unknown parameter
|month=ignored (help)