Finaale pulmonary stenosis

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  • 1. FuadFuadFarooqFarooq
  • 2.  Pulmonary Stenosis (PS) has beenPulmonary Stenosis (PS) has beendescribed in 1761 by Morgagnidescribed in 1761 by Morgagni It accounts for 20-30% of all CHDIt accounts for 20-30% of all CHD Found in 8% to 10% of patients as isolatedFound in 8% to 10% of patients as isolatedPSPS In 50% of cases the septum is intactIn 50% of cases the septum is intact
  • 3. Three anatomical varientsThree anatomical varients Valvar (90%)Valvar (90%) Subvalvar (Subvalvar (Infundibular stenosisInfundibular stenosisfrom hypertrophy of the Cristafrom hypertrophy of the CristaSupraventricularis)Supraventricularis) Supravalvar (pulmonary artery trunkSupravalvar (pulmonary artery trunkor branches )or branches )
  • 4. Pulmonary valve stenosis is usuallyPulmonary valve stenosis is usuallyisolated or part of the complex congenitalisolated or part of the complex congenitalheart diseaseheart disease
  • 5.  Exact embryologic process is not wellExact embryologic process is not wellunderstoodunderstood Mal-development of the distal part of the bulbusMal-development of the distal part of the bulbuscordiscordis Genetic factors may play a roleGenetic factors may play a role Known association between pulmonary valve andKnown association between pulmonary valve andsupravalvular stenosis with multiple somaticsupravalvular stenosis with multiple somaticabnormalitiesabnormalities
  • 6.  Valve commisures are partially fused and the 3Valve commisures are partially fused and the 3leaflets are thin and pliant, resulting in a conicalleaflets are thin and pliant, resulting in a conicalor dome-shaped structure with a narrowedor dome-shaped structure with a narrowedcentral orificecentral orifice It may be diffusely thickened with one, two, orIt may be diffusely thickened with one, two, orthree leaflets and commissural fusionthree leaflets and commissural fusion
  • 7. Bicuspid valve is found in 90% of patientsBicuspid valve is found in 90% of patientswith Tetralogy of Fallotwith Tetralogy of Fallot Rare in individuals with isolated valvular PSRare in individuals with isolated valvular PS
  • 8. 10-15% of individuals with valvular PS have10-15% of individuals with valvular PS havedysplastic pulmonary valvesdysplastic pulmonary valves Valves have irregularly shaped, thickenedValves have irregularly shaped, thickenedleaflets, with little commissural fusion and exhibitleaflets, with little commissural fusion and exhibitreduced mobilityreduced mobility The leaflets are composed of myxomatous tissue,The leaflets are composed of myxomatous tissue,which may extend to the vessel wallwhich may extend to the vessel wall The valve annulus is usually small and theThe valve annulus is usually small and thesupravalvular area of the pulmonary trunk issupravalvular area of the pulmonary trunk isusually hypoplasticusually hypoplastic Poststenotic dilatation of the pulmonary artery isPoststenotic dilatation of the pulmonary artery isuncommonuncommon
  • 9.  Secondary changes in the right ventricle andSecondary changes in the right ventricle andpulmonary arteriespulmonary arteries Right ventricle espacially infundibular regionRight ventricle espacially infundibular regionbecomes diffusely hypertrophiedbecomes diffusely hypertrophied Produce dynamic subvalvular obstructionProduce dynamic subvalvular obstruction Right atrium may be thick and dilate as aRight atrium may be thick and dilate as aresult of the increased pressure necessaryresult of the increased pressure necessaryto fill the hypertrophic right ventricleto fill the hypertrophic right ventricle
  • 10.  Rise in RV pressure proportional to theRise in RV pressure proportional to theseverity of obstructionseverity of obstruction Increase in muscle massIncrease in muscle mass Hyperplasia of the muscle cells with aHyperplasia of the muscle cells with aconcomitant increase in the number of capillariesconcomitant increase in the number of capillaries Increased muscle mass may enable theIncreased muscle mass may enable thehypertensive right ventricle to maintain ahypertensive right ventricle to maintain anormal stroke volumenormal stroke volume
  • 11.  Development of poststenotic dilation ofDevelopment of poststenotic dilation ofthe pulmonary artery trunk sometimesthe pulmonary artery trunk sometimesextending to the proximal left pulmonaryextending to the proximal left pulmonaryarteryartery Result from the high velocity jet of flow ejectedResult from the high velocity jet of flow ejectedthrough the small valve orifice - “jet effect”through the small valve orifice - “jet effect” The degree of dilation is not necessarilyThe degree of dilation is not necessarilyproportional to the severity of obstructionproportional to the severity of obstruction
  • 12. RV eventually dilate and failRV eventually dilate and failExacerbated by:Exacerbated by: Development of tricuspid insufficiencyDevelopment of tricuspid insufficiency Subendocardial (esp. at infundibular region) andSubendocardial (esp. at infundibular region) andpapillary muscle ischemia/infarctionpapillary muscle ischemia/infarction
  • 13.  Mostly diagnosis is made when murmurMostly diagnosis is made when murmurdetected in asymptomatic patients on routinedetected in asymptomatic patients on routineexaminationexamination Exertional dyspnea, fatigue and cynosis dueExertional dyspnea, fatigue and cynosis dueto inability of the right ventricle to increase itsto inability of the right ventricle to increase itsoutput in response to exertionoutput in response to exertion If the stenosis is not relieved then features ofIf the stenosis is not relieved then features ofright heart failureright heart failure
  • 14. Chest pain, syncope and sudden deathChest pain, syncope and sudden deathwith strenuous exercisewith strenuous exerciseDecreased myocardial perfusion caused byDecreased myocardial perfusion caused byinadequate cardiac output during exercise,inadequate cardiac output during exercise,leading to ischemia and ventricular arrhythmiasleading to ischemia and ventricular arrhythmias
  • 15. ‘‘a’ wave becomes progressively largera’ wave becomes progressively largerwith increasing severity of obstructionwith increasing severity of obstruction
  • 16.  Left parasternal heaveLeft parasternal heave Systolic thrill in severe pulmonarySystolic thrill in severe pulmonarystenosisstenosis Located at the 2Located at the 2ndndto 3to 3rdrdintercostal space butintercostal space butit may also be felt at the suprasternal notchit may also be felt at the suprasternal notch Absent in young infants with severe stenosisAbsent in young infants with severe stenosisand in patients with congestive heart failureand in patients with congestive heart failureand low cardiac outputand low cardiac output
  • 17. S1 normal followed by a pulmonaryS1 normal followed by a pulmonaryejection click in patients with mild orejection click in patients with mild ormoderate stenosismoderate stenosis Corresponds to the time when the domingCorresponds to the time when the domingpulmonary valve reaches its open positionpulmonary valve reaches its open position Become earlier as severity increased until itBecome earlier as severity increased until itmerges with the first heart sound andmerges with the first heart sound andbecomes inaudiblebecomes inaudible
  • 18. Click is followed by ESM maximal at theClick is followed by ESM maximal at theupper left sternal borderupper left sternal borderIntensity – increases with the severity of obstructionIntensity – increases with the severity of obstructionRadiation – entire precordium, neck & backRadiation – entire precordium, neck & back(characteristically)(characteristically)Become soft when severe stenosis with right heartBecome soft when severe stenosis with right heartfailure due to low cardiac outputfailure due to low cardiac output
  • 19. P2 intensity typically decreases withP2 intensity typically decreases withincrease severity of obstructionincrease severity of obstruction
  • 20.  S4 – lower left sternal border in patients withS4 – lower left sternal border in patients withsevere stenosissevere stenosis Pansystolic murmur of tricuspid insufficiencyPansystolic murmur of tricuspid insufficiencymay be present lower along the left sternalmay be present lower along the left sternalborderborder S3 – when present think of ASDS3 – when present think of ASD
  • 21. Mild stenosis usually have a normalMild stenosis usually have a normalelectrocardiogramelectrocardiogramRightward axis deviation is often the only abnormalityRightward axis deviation is often the only abnormality
  • 22. Electrocardiogram is almost alwaysElectrocardiogram is almost alwaysabnormalabnormal Right axis deviationRight axis deviation The R:S ratio in V1 is usually >4:1The R:S ratio in V1 is usually >4:1 R wave is typically <20 mmR wave is typically <20 mm The T waves in the right precordial leads areThe T waves in the right precordial leads areupright in approximately 50% of patientsupright in approximately 50% of patients
  • 23.  QRS axis >110 degrees and not uncommonly extremeQRS axis >110 degrees and not uncommonly extremeRADRAD A pure R, Rs, or QR is the usual pattern in the rightA pure R, Rs, or QR is the usual pattern in the rightprecordial leads, and the R wave is usually >20 mmprecordial leads, and the R wave is usually >20 mm The R:S ratio in VThe R:S ratio in V66 may be <1.0may be <1.0 The T waves usually inverted in the right precordial leadsThe T waves usually inverted in the right precordial leads P-pulmonale indicating right atrial enlargementP-pulmonale indicating right atrial enlargement
  • 24. Estimation of RV pressure is possibe if a pure REstimation of RV pressure is possibe if a pure Rwave is present in lead Vwave is present in lead V4R4R or Vor V11The height of the R wave in millimeters,The height of the R wave in millimeters,multiplied by 5, approximates the rightmultiplied by 5, approximates the rightventricular pressure in mm of Hgventricular pressure in mm of Hg
  • 25.  Enlarged main pulmonary artery secondaryEnlarged main pulmonary artery secondaryto post-stenotic dilatationto post-stenotic dilatation Enlarged left pulmonary artery (jet streamEnlarged left pulmonary artery (jet streameffect)effect) Normal to decreased peripheral pulmonaryNormal to decreased peripheral pulmonaryvasculaturevasculature CardiomegalyCardiomegaly Results from RA and RV enlargementResults from RA and RV enlargement
  • 26.  Standard and high parasternal short and longStandard and high parasternal short and longaxis views and the subcostal sagittal viewsaxis views and the subcostal sagittal views Valve leaflets usually appear prominent becauseValve leaflets usually appear prominent becauseof thickeningof thickening Systolic motion is restricted, with inward curvingSystolic motion is restricted, with inward curvingof the tips of the leaflets, known as domingof the tips of the leaflets, known as doming Poststenotic dilation of the main and branchPoststenotic dilation of the main and branchpulmonary arteries are also easily recognizedpulmonary arteries are also easily recognized
  • 27.  Assessment of RV anatomy and function andAssessment of RV anatomy and function andassessment of tricuspid valveassessment of tricuspid valve Evidence of dynamic subpulmonary stenosisEvidence of dynamic subpulmonary stenosisshould be soughtshould be sought Dysplastic pulmonary valve usually can beDysplastic pulmonary valve usually can beascertained by echocardiographyascertained by echocardiography The leaflets appear thickened and immobile,The leaflets appear thickened and immobile,without the characteristic doming seen in typicalwithout the characteristic doming seen in typicalcasescases The pulmonary valve annulus is hypoplastic, andThe pulmonary valve annulus is hypoplastic, andsupra-annular narrowing of the proximal mainsupra-annular narrowing of the proximal main
  • 28.  Allows quantitative assessment of severityAllows quantitative assessment of severityof pulmonary valve stenosisof pulmonary valve stenosis The echo beam must be aligned parallelThe echo beam must be aligned parallelwith the main pulmonary artery trunk orwith the main pulmonary artery trunk orthe direction of the flow jet as seen onthe direction of the flow jet as seen oncolor Dopplercolor Doppler Excellent correlation between the Doppler-Excellent correlation between the Doppler-derived gradient and that obtained byderived gradient and that obtained by
  • 29.  Role of catheterization has becomeRole of catheterization has becomelargely limited in therapeuticslargely limited in therapeutics
  • 30.  Measurement of RV pressure andMeasurement of RV pressure andcompared with systemic arterial pressurecompared with systemic arterial pressureand the pressure gradient across theand the pressure gradient across thepulmonary valvepulmonary valve Resting RV pressure >30 to 35 mm HgResting RV pressure >30 to 35 mm Hgand pressure gradient across theand pressure gradient across thepulmonary valve of >10 are consideredpulmonary valve of >10 are consideredabnormalabnormal
  • 31. RV pressures 105 mmHg and PA pressures are 60, so the gradient is 45 mmHg
  • 32.  If associated infundibular obstruction, pressureIf associated infundibular obstruction, pressuregradients are encountered across the pulmonarygradients are encountered across the pulmonaryvalve and also across the infundibulumvalve and also across the infundibulum RVEDP may be normal but usually elevated withRVEDP may be normal but usually elevated withsevere obstruction or right ventricular failuresevere obstruction or right ventricular failure Right atrial pressure is normal in mild toRight atrial pressure is normal in mild tomoderate obstruction, but tall right atrial ‘A’moderate obstruction, but tall right atrial ‘A’waves usually are seen with severe obstructionwaves usually are seen with severe obstruction
  • 33.  Provides information about the locationProvides information about the locationand severity of pulmonary stenosis that isand severity of pulmonary stenosis that isinvaluable for diagnostic and therapeuticinvaluable for diagnostic and therapeuticpurposespurposes Anatomy of the pulmonary valve andAnatomy of the pulmonary valve andassociated features can be shown best byassociated features can be shown best byright ventricular angiography in theright ventricular angiography in theanteroposterior cranial and lateral viewanteroposterior cranial and lateral view
  • 34.  Normal pulmonary valve area is 2.0 cmNormal pulmonary valve area is 2.0 cm22/m/m22of BSAof BSAMild stenosis- Valve area largerthan 1 cm2- Right ventricularpressure less thanhalf the leftventricularpressure- Peak gradient10-35 mm Hg- Peak velocity<3m/secModerate stenosis- Valve area 0.5-1.0 cm2- Right ventricularpressure is greaterthan half but <75%of the leftventricularpressure- Peak gradient is36-64 mm Hg- Peak velocity 3-4m/secSevere stenosis- Valve area <0.5cm2-Right ventricularpressure 75% of the leftventricular pressure -Peak gradient >64 mmHg- Peak velocity >4/sec
  • 35.  Idiopathic dilation of the main pulmonary arteryIdiopathic dilation of the main pulmonary artery ASDASD Peripheral pulmonary arterial stenosisPeripheral pulmonary arterial stenosis Mitral valve prolapseMitral valve prolapse Straight back syndromeStraight back syndrome Aortic stenosisAortic stenosis Innocent murmursInnocent murmurs VSD with or without associated pulmonaryVSD with or without associated pulmonarystenosisstenosis Tetralogy of FallotTetralogy of Fallot Pulmonary atresia with intact ventricular septumPulmonary atresia with intact ventricular septum Ebstein anomaly of the tricuspid valveEbstein anomaly of the tricuspid valve
  • 36.  Noonan syndrome in 50% of patientsNoonan syndrome in 50% of patients Most common lesion is pulmonary stenosis owing to pulmonaryMost common lesion is pulmonary stenosis owing to pulmonaryvalve dysplasiavalve dysplasia 25% of Hypertrophic CMP of the left ventricle with PS25% of Hypertrophic CMP of the left ventricle with PS Rarely - cardiac tumors can grow on or into the RVRarely - cardiac tumors can grow on or into the RVoutflow tract and cause flow obstructionoutflow tract and cause flow obstruction Extrinsic lesions e.g., Sinus of Valsalva aneurysms andExtrinsic lesions e.g., Sinus of Valsalva aneurysms andaortic graft aneurysms compressing cardiac structuresaortic graft aneurysms compressing cardiac structuresand can cause PSand can cause PS Multiple lentigines syndrome, or leopard syndrome, hasMultiple lentigines syndrome, or leopard syndrome, hasbeen associated with pulmonary valve and pulmonarybeen associated with pulmonary valve and pulmonaryartery stenosisartery stenosis
  • 37.  Neurofibromatosis, deposits from glycogen storageNeurofibromatosis, deposits from glycogen storagediseases and goutdiseases and gout Carcinoid results in development of myxomatousCarcinoid results in development of myxomatous(fibroelastic) plaques in the RV outflow tract(fibroelastic) plaques in the RV outflow tract Distortion and constriction of the pulmonic ring, as well as fusionDistortion and constriction of the pulmonic ring, as well as fusionor destruction of pulmonary valve leaflets, resulting in bothor destruction of pulmonary valve leaflets, resulting in bothstenosis and regurgitationstenosis and regurgitation Rare manifestation of rheumatic heart disease - followsRare manifestation of rheumatic heart disease - followsinvolvement of the mitral and aortic valvesinvolvement of the mitral and aortic valves
  • 38.  Valvuloplasty should be performed in anyValvuloplasty should be performed in anysymptomatic patient as soon as thesymptomatic patient as soon as thediagnosis is madediagnosis is made Immediate valvoplasty in infants withImmediate valvoplasty in infants withcritical pulmonary valve stenosiscritical pulmonary valve stenosis Asymptomatic patients with severeAsymptomatic patients with severeobstruction should be treatedobstruction should be treatedsemielectively with valvuloplasty shortlysemielectively with valvuloplasty shortly
  • 39.  Moderate obstruction should undergoModerate obstruction should undergoelective valvuloplasty if the rightelective valvuloplasty if the rightventricular pressure is 50% systemic orventricular pressure is 50% systemic orhigherhigher No intervention is necessary for patientsNo intervention is necessary for patientswith mild obstructionwith mild obstruction They should not be restricted in their physicalThey should not be restricted in their physicalactivity and should be treated as normalactivity and should be treated as normalchildrenchildren
  • 40.  Described initially by Kan and associates inDescribed initially by Kan and associates in19821982 After obtaining appropriate hemodynamic andAfter obtaining appropriate hemodynamic andangiographic information about severity andangiographic information about severity andlocation of obstruction, an exchange guidewire islocation of obstruction, an exchange guidewire isintroduced through an end-hole catheter andintroduced through an end-hole catheter andpositioned in the distal left pulmonary arterypositioned in the distal left pulmonary artery A balloon is chosen that is 20% to 40% largerA balloon is chosen that is 20% to 40% largerthan the angiographically measured pulmonarythan the angiographically measured pulmonaryvalve annulus, and it is positioned over avalve annulus, and it is positioned over aguidewire with the valve at its midpointguidewire with the valve at its midpoint In larger patients with an annulus diameter ofIn larger patients with an annulus diameter of>20 mm, the double-balloon technique may be>20 mm, the double-balloon technique may be
  • 41.  Independent predictors of suboptimalIndependent predictors of suboptimalintermediate-term outcomeintermediate-term outcome Small annular size (characteristic of patientsSmall annular size (characteristic of patientswith dysplastic valves)with dysplastic valves) Higher immediate residual gradientHigher immediate residual gradient Earlier year of the initial valvuloplastyEarlier year of the initial valvuloplasty Smaller balloon to annulus ratioSmaller balloon to annulus ratio
  • 42.  Death (0.2%)Death (0.2%) Laceration of the inferior vena cava, iliac veinLaceration of the inferior vena cava, iliac veinjunction during balloon withdrawaljunction during balloon withdrawal Tearing of the pulmonary valve annulus duringTearing of the pulmonary valve annulus duringballoon inflationballoon inflation Perforation of the right ventricular outflowPerforation of the right ventricular outflowtract resulting in tamponade and tricuspidtract resulting in tamponade and tricuspidregurgitation requiring surgical interventionregurgitation requiring surgical intervention Vein thrombosis and vein tearsVein thrombosis and vein tears Arrhythmias (1.3%)Arrhythmias (1.3%)
  • 43.  Stroke, seizures, necrotizing enterocolitis,Stroke, seizures, necrotizing enterocolitis,endocarditis and septic shockendocarditis and septic shock Abrupt closure of the ductus despiteAbrupt closure of the ductus despiteprostaglandin infusion requiring urgentprostaglandin infusion requiring urgentaortopulmonary shunt placementaortopulmonary shunt placement Pulmonary insufficiencyPulmonary insufficiency Risk factors: smaller body surface area at theRisk factors: smaller body surface area at thetime of intervention, larger balloon to annulustime of intervention, larger balloon to annulusratio and a higher degree of obstructionratio and a higher degree of obstructionbefore dilationbefore dilation
  • 44.  Reserved for dysplastic pulmonary valvesReserved for dysplastic pulmonary valvesresistant to dilation or with multiple levels ofresistant to dilation or with multiple levels offixed obstructionfixed obstruction Often a persistent pressure gradient immediatelyOften a persistent pressure gradient immediatelyafter surgery in patients with isolated valvarafter surgery in patients with isolated valvarpulmonary stenosis attributable to dynamicpulmonary stenosis attributable to dynamicnarrowing of the hypertrophied infundibulum (asnarrowing of the hypertrophied infundibulum (asalso observed following balloon valvuloplasty)also observed following balloon valvuloplasty) Reduction in gradient occur in the first 24 hoursReduction in gradient occur in the first 24 hoursafter surgery and continues at a slower rate asafter surgery and continues at a slower rate asthe hypertrophy resolves over the subsequentthe hypertrophy resolves over the subsequent
  • 45.  Presence of symptoms such asPresence of symptoms such asprogressive decrease in exerciseprogressive decrease in exercisetolerance or functional class or evidencetolerance or functional class or evidenceof right heart failureof right heart failure Progressive RV enlargement oftenProgressive RV enlargement oftenaccompanied by increasing TR owing toaccompanied by increasing TR owing toannular dilationannular dilation Development or progression of atrialDevelopment or progression of atrial
  • 46.  Homograft valves, xenograft valves,Homograft valves, xenograft valves,pericardial valves, and mechanical valvespericardial valves, and mechanical valves Percutaneous pulmonary valvePercutaneous pulmonary valvereplacement with a bovine jugular venousreplacement with a bovine jugular venousvalve sutured inside a stent was firstvalve sutured inside a stent was firstdescribed in a human in 2000described in a human in 2000
  • 47.  Symptoms are unreliable in reflectingSymptoms are unreliable in reflectinghemodynamic severity because theyhemodynamic severity because theyusually are seen only in patients withusually are seen only in patients withsevere or critical obstructionsevere or critical obstruction The course of mild stenosis is benignThe course of mild stenosis is benign No intervention is requiredNo intervention is required The hemodynamic response to exercise inThe hemodynamic response to exercise inthese patients is normalthese patients is normal
  • 48.  Patients with moderate stenosis may developPatients with moderate stenosis may developprogressively greater outflow tract obstruction,progressively greater outflow tract obstruction,especially during periods of rapid growthespecially during periods of rapid growth In most asymptomatic patients with moderateIn most asymptomatic patients with moderatepulmonary valve stenosis formal exercise testingpulmonary valve stenosis formal exercise testingdemonstrated subnormal cardiac outputdemonstrated subnormal cardiac outputresponse and abnormal increase in rightresponse and abnormal increase in rightventricular end-diastolic pressure suggestingventricular end-diastolic pressure suggestingthat both systolic and diastolic dysfunction maythat both systolic and diastolic dysfunction maybe caused by long-standing moderatebe caused by long-standing moderate
  • 49.  Children with severe stenosis commonlyChildren with severe stenosis commonlydevelop increasingly severe obstructiondevelop increasingly severe obstruction Result from disproportionate growth of theResult from disproportionate growth of thechild relative to the pulmonary valvechild relative to the pulmonary valve Exercise hemodynamics in children andExercise hemodynamics in children andadults with severe obstruction before andadults with severe obstruction before andafter valvotomy suggest that irreversibleafter valvotomy suggest that irreversiblechanges in cardiac function can develop ifchanges in cardiac function can develop iftreatment is delayed beyond childhoodtreatment is delayed beyond childhood
  • 50.  Patients with severe stenosis have a lowerPatients with severe stenosis have a lowercardiac stroke index at rest and during exercisecardiac stroke index at rest and during exerciseand also higher RVEDP at rest and abnormaland also higher RVEDP at rest and abnormalincrease with exercise than patients with milderincrease with exercise than patients with milderdiseasedisease Following valvotomy there is an improvement inFollowing valvotomy there is an improvement instroke index and reduction in RVEDP at rest andstroke index and reduction in RVEDP at rest andduring exercise within 1 year of operationduring exercise within 1 year of operation In contrast this improvement is not observed inIn contrast this improvement is not observed inolder patientsolder patients Implying permanent changes e.g., myocardial fibrosisImplying permanent changes e.g., myocardial fibrosishave occurredhave occurred
  • 51.  5% of all cases of right ventricular outflow5% of all cases of right ventricular outflowtract obstructiontract obstruction Two types:Two types: Obstructive fibrous band at the junction of theObstructive fibrous band at the junction of themain right ventricular cavity and the proximalmain right ventricular cavity and the proximalinfundibulum that closely resembles double-infundibulum that closely resembles double-chambered right ventriclechambered right ventricle Narrowing of the infundibulum is due toNarrowing of the infundibulum is due tofibromuscular thickening of its wall, which mayfibromuscular thickening of its wall, which mayextend from immediately below the pulmonaryextend from immediately below the pulmonaryvalve to the proximal infundibulumvalve to the proximal infundibulum
  • 52.  ““Double-chambered right ventricle“Double-chambered right ventricle“ Aberrant hypertrophied muscular bands - divideAberrant hypertrophied muscular bands - dividethe RV cavity into a proximal high-pressurethe RV cavity into a proximal high-pressurechamber and a distal low-pressure chamber tochamber and a distal low-pressure chamber tothe hypertrophied muscle bandsthe hypertrophied muscle bands Orientation differs from that of the moderatorOrientation differs from that of the moderatorbandband Septal attachment of the moderator band is usually inSeptal attachment of the moderator band is usually inthe apical third of the ventricular septumthe apical third of the ventricular septum Septal attachment of anomalous muscle bundles areSeptal attachment of anomalous muscle bundles are
  • 53.  Visualized best from – subcostal andVisualized best from – subcostal andparasternal viewsparasternal views Presence or absence of a ventricularPresence or absence of a ventricularseptal defect can be documentedseptal defect can be documented Abnormal fluttering of the pulmonary valveAbnormal fluttering of the pulmonary valveis often a concomitant findingis often a concomitant finding Treatment is surgical correctionTreatment is surgical correction