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Right Heart Failure: When it’s on the Right, don’t be Wrong.

The Causes, Diagnosis and Treatment of Right-sided Heart Failure

WhitChurch,DVM,DiplomateACVIM(Cardiology)DesertVeterinaryMedicalSpecialists,Gilbert,AZ

CentralVenousPressure•  Forceexertedbythebloodagainstanyunitareaofthevesseloratrialwall

•  Unitsofpressure– mmHg– cmwater

•  1mmHg=1.36cmH20

Right-sidedCongestiveHeartFailureusuallyoccursat>10mmHg(13.6cmofWater)

Signalment

•  DCM–  Dobermanpinscher,Boxer,GreatDane

•  Mitralvalvedisease–  CavalierKingCharlesSpaniel,Chihuahua,Maltese

•  PulmonaryHypertension– WestHighlandWhite,YorkshireTerriers,Pug

•  CompleteAVBlock–  Cockerspaniels

•  Heartworm–  AnyBreed!

Excellent review: Buchanan J. Current Vet Therapy XII

Common Breed Predispositions

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History/ClinicalSigns

•  Ascites•  CardiogenicSyncope

– ExerciseInduced–  InadequateCO

• Outflowobstruction– Hypoxemia

•  Tachypnea•  CutaneousEdema•  ExerciseIntolerance

CardiogenicCollapse

•  Thefamilyshouldbequestionedabouttheevent.– Whatactivityprecededtheevent?– Whatdidtheeventlooklike?–  Howlongdiditlast?–  Describetherecovery

•  Knowingthecommondiseasesofthebreedoftenguideourdecisions.•  Largebreeddogswithsyncopeareusuallymorelikelytohaveventricular

tachycardia•  Smallerbreedstendtohavebradyarrhythmiasmorecommonly.

•  Smallerbreedsyncopeisalsomorecommonlynon-arrhythmic(SevereMVDorPulmonaryHypertension)

Cardiovascular Physical Exam AbnormalArterialPulses

•  Decreasedamplitude,weak(hypokinetic)–  Lowstrokevolume–  LVoutflowobstruction

•  PulsusParadoxus–pericardialeffusion

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PhysicalExamination

•  RIGHT-sidedMurmur–  Indicatesright-sideddiseaseis

likely

– Specificbutnotsensitiveforpresenceofdisease

– LooseIndicatorofseverityofdisease

•  “Falsenegatives”– Nomurmur,butseveredisease.

PhysicalExamination

•  JugularPulseorDistention–  Indicatesright-sidedpressure

elevationislikely

– Specificbutnotsensitiveforpresenceofdisease

•  AbdominalDistension•  CutaneousEdema•  WeakFemoralPulse

CharacteristicsofThePulmonaryCirculation

•  Lowpressure,Lowresistancecircuit– Vasoconstrictioninresponsetohypoxiaisthefundamentaldifferenceofpulmonarybloodvesselscomparedtosystemicvessels.

– ThisisduetoHypoxicPulmonaryVasoconstriction(HVP),Stillapoorlyelucidatedreflex.

– Constrictionofthesmallarteriolesoccurswithinafewsecondsofreducedoxygenconcentrationandpeaksbetween2-4hoursaftertheonsetofhypoxia.

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PulmonaryHypertension

•  CausesofPulmonaryArterialHypertension(PAH)–  PrimaryPulmonaryDisorders–  ChronicLeftHeartDisease(Pulm.VenousHypertension)

– HeartwormDisease–  Pulmonaryembolismorin-situthrombosis–  Primarypulmonaryhypertension–  Congenitalsystemic-to-pulmonaryshunt–  Portopulmonaryhypertension(ThoughttoberelatedtoincreasedlevelsofEndothelin-1.

PulmonaryHypertension

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Pathophysiology

KeystoEvaluation•  Historyofaggravating

morbidities•  PresenceofPhysical

ExaminationAbnormalities•  Heartsize

–  Reflectslevelofneurohormonalactivation

–  Reflectsseverityofdisease•  Pulmonaryarterypressures

–  Reflectsriskofmorbidityandmortality

•  ResponsetoTherapy–  Canhelpdetermineunderlying

cause

WhatinfodoIneednext?

q  Thoracic Radiography

q  Echocardiography

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DiagnoseTheDiseaseEchocardiographyisthe“GoldStandard”forDiagnosisofStructuralCardiacDisease

• Assesssystolicanddiastolicfunction.

• Bestnoninvasiveassessmentofpulmonaryarterypressures,leftatrialandrightventricularpressures.• Can also help assess systemic blood pressure and “White Coat Syndrome”

PulmonaryHypetensionThe Vmax of the tricuspid insufficiency jet approximates the systolic pulmonary artery pressure.

Pulmonary Hypertension

The Vmax of the pulmonic insufficiency jet approximates the mean pulmonary artery pressure.

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Pulmonary Hypertension n RightVentricularAccelerationandEjectionTime

Schober K, Baade H; J Vet Intern Med 2006;20:912–920

Sildenafil•  SildenafilisatypeVphosphodiesteraseinhibitorthatproducesnitricoxidemediatedvasodilatationofthepulmonaryvasculature.

•  Rapidonset:Within15min.andpeakeffectat2hours.HalfLifeis4hours.

•  Thisdrugclasscanslightlyreducearterialsystemicbloodpressure,butisoneofthemostselectiveforthepulmonaryvasculature.

§  Inodilation:CalciumSensitizerPDEIIIInibitorPDEVInhibitorSamemechanism

asViagra

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Katarzyna(Kasia)

•  10-yrold,FSPugpresentstoyourhospitalforareducedappetiteforthelast3days,recentlethargy,progressiveabdominaldistention,andasingleepisodeofcollapsethatoccurredthismorning,historyofsevere,assymptomaticmitraldisease.Notcurrentlyonanymedications

•  IV/VIleftandrightapicalsystolicmurmur

•  Regularheartrhythm

•  Normallungsounds

Katarzyna(Kasia)

•  10-yrold,FSPugpresentstoyourhospitalforareducedappetiteforthelast3days,recentlethargy,progressiveabdominaldistention,andasingleepisodeofcollapsethatoccurredthismorning,historyofsevere,assymptomaticmitraldisease.Notcurrentlyonanymedications

•  IV/VIleftandrightapicalsystolicmurmur

•  Regularheartrhythm

•  Normallungsounds

Kasia:Radiographs

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Kasia

Kasia:ECG

Kasia:AdditionalRhythmDiagnostics

•  Limitationsofin-hospitalECGandHRmeasurement

•  24-hourambulatory(Holter)monitoring

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Kasia:Echo

TricuspidRegurgitatoinVelocityThe Vmax of the tricuspid insufficiency jet approximates the systolic pulmonary artery pressure.

DVD CHF and Pulmonary Hypertension

q  An echocardiogram reveals severe degenerative valve disease with moderate pulmonary hypertension. Moderate to severe volume ascites. The ECG shows sinus rhythm. Normal systolic function with severe left-sided and modest right-sided cardiomegally. Mitral inflows are consistent with left atrial pressures >20mmHg.

q  Right-sided Congestive Heart Failure.

KASIA: 10yr old, FS, Pug

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Question

•  Whatshouldwedofirst?•  WhatChronicTherapyPrescribed•  Whattypeoffollow-up

Treatment of Right Heart Failure If you can take it out with a needle, what are you waiting for?

Recommended Medications:

TheLIVProtocolTripletherapy

Lasix(~2mg/kg/day)ACEInhibitor(Enalapril 0.5 mg/kg BID)Vetmedin(Pimobendan0.3mg/kgBID)

Sildenafil???Spironolactone???

Kasia:DVD,CHF,PHTChronicTreatment

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PulmonaryHypertensionTreatment

•  ChronicTreatment:– Sildenafil– Vetmedin– HeparinorLMWH– L-Arginine(NOSconvertstoNO)– Amlodipine– HeartwormTreatment– ACEInhibitors– Diuretics

Bradyarrhythmias

These patients die suddenly or if they live long enough, they go into right heart failure.

Ø  Stimulants used: Theophylline, Propantheline.

Ø  Artificially pace them as soon as possible.

ECG q  Complete AV Block

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ECG q  Atrial Standstill

Treatment of Arrhythmias

Ø  Stimulants used: Theophylline, Propantheline.

Ø  Artificially pace them as soon as possible.

Ø  “LIV Protocol” in Heart Failure Patients

Ø  Poor Prognosis without pacing.

Snowy:3yr,FS,ShepherdMix

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Snowy:3yr,FS,ShepherdMix

Snowy:3yr,FS,ShepherdMix

Snowy:3yr,FS,ShepherdMix

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Snowy:3yr,FS,ShepherdMix

Snowy:3yr,FS,ShepherdMix

HeartworminArizona

•  ThereareconsistentlymorecasesofheartwormdiagnosedinArizonaeachyear.ThemapsbelowshowtheincreaseinreportedcasesinUSAin2007and2016.TakenoteoftheincreasedcolordensityofMaricopaandPimacounties.

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ArizonaHeartwormIncidence2007

ArizonaHeartwormIncidence2016

HeartwormTreatment•  Ifthedogissymptomatic:

•Stabilizewithappropriatetherapyandnursingcare•Prednisonetherapyshouldbeusedasanimmediateantiinflammatoryforthearteritis,pneumonitis,andtorelievesymptomsassociatedwiththromboembolism.

•  Anivermectinbasedheartwormpreventativeshouldbeadministeredfor60dayspriortoMelarsomine.

•  Doxycycline(10mg/kgBIDfor4weeks)shouldbeadministeredfor60dayspriortoMelarsomine.BenefitsthepatientbykillingtheWolbachiabacteriaspeciesinthegastrointestinaltractofthedirofilariaimmitisparasitewhichmaybepartiallyresponsibleforthesevereinflammatoryreactiontotheheartwormparasite,andallowinga30day“washout”periodforWolbachiaSurfaceProteins

•  Conservative(3Dose)melarsomine(Immiticide)protocol.

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HeartwormTreatment

1.  One2.5mg/kgdeepepaxialmuscleinjectionfollowedby4weeksofconfinementwithnoexerciseotherthanoutsidetousetherestroom.

2.  Asecond2.5mg/kgdoseofmelarsomineviadeepepaxialmuscleinjectionshouldbegiven.

3.  24hourslaterathirddeepepaxialmuscle2.5mg/kginjectionofmelarsomineshouldbeadministered.Thismakesatotalof3injections,onedose,wait4weeks,andthen2doses24hoursapart.Afterthefinaldoseofmelarsomine,thepatientmustbeconfinedforanadditional4weeks.

4.  MonthlyivermectinbasedheartwormpreventionandPrednisoneshouldbecontinuedthroughoutthemelarsominetreatment.

5.  Adulticidetherapycanbeassociatedwithcomplicationsthatincluderespiratorydistress,anemia,ascites,cyanosis,kidneyorliverfailure,andsuddendeath.

6.  Thecardiacandpulmonarychangesmaybeapersistentproblemdespiteresolutionoftheactiveheartworminfection,butmostdogscanreturntoanasymptomaticformofpulmonaryhypertensionandinactivepneumonitis.

Conservative(3Dose)melarsomine(Immiticide)protocol.

HeartwormTreatment

•  Retestantigenandformicrofilariain6months!Conservative(3Dose)melarsomine(Immiticide)protocol.

Leo : 10yr old MN Pom l  Familycomplaintoflabored,noisybreathingwithanydegreeofexcitement,

andoftenoccursatrestaswell.Afterbeingasked,theownersadmittoachroniccoughoverthelast6yearsthatalwaysoccurredwithexcitement.

l  Grade II/VI right apical Systolic murmur l  Mildly tachycardic (HR=160) l  Referred upper airway noise l  Normal pulse strength and Mild jugular

distention l  Loud noise with each expiration l  Current medications: None

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Leo’s Radiographs

Leo’sRadiographs

Leo’s ECG

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Leo:Echocardiogram

Leo’s Echo

Leo’s Echo

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Leo:Echocardiogram

Leo:Echocardiogram

Leo’s Echo

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Question

•  What treatment protocol should be start:

•  LIV •  Antibiotics •  Sildenafil •  Cough Suppression and Steroids

Leo l  Radiographicinterpretation:Severetrachealcollapsewithmildatelectasis

inthecaudallungfieldsonthelateralview.Cardiacsilhouetteappearsenlarged,withsuspectedrightheartenlargement.Pulmonaryvasculatureisnotwellvisualized,butdoesappearwithinnormallimits.

l  Echocardiophic Interpretation: Patienthasmilddegenerativevalvedisease,buttheheartenlargementisduetoseverepulmonaryhypertensionTRPG=98mmHg.Patientalsohasmildascites.l  Recommendedmedications:

l  Sildenafil1-2mg/kgBID-TIDl  LIV

Leo’s Additional Treatments

1  Hydrocodone0.5mg/kgBIDtoTIDasneededforcough.2  Ifcoughdoesnotimprove:Prednisone0.25mg/kgBID

taperingdoseover3weeks.3  Consider Bronchodilators: Theophylline 4  Weight Loss 5  Environmental Control 6  Harness

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Teton

q  Presents with a complaint of panting, weakness, anxiousness, inappetance, and abdominal distention.

q  HR=140/min with a regular rhythm

q  Weak and variable femoral pulses

q  No cardiac murmur, but a jugular pulse is present.

8yr old, MN, Bernese Mountain Dog

Teton:ArterialPulseTracing

Question

•  Pulsusparadoxusisalmostpathognomonicforwhichcardiovascularproblem:

•  DCM•  Valvularheartdisease•  Heartwormdisease•  Pericardialeffusion

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LeadIIRhythmStrip

Question

•  WastheECGHelpful?

•  Yes•  No

Answer:yesElectricalAlternansandsmallQRScomplexessuggestpericardialeffusion.

Teton’sRadiographs

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Radiographic Findings

Teton’s:Echocardiogram

Treatment of Cardiac tamponade q  Cardiac tamponade

V

P

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Hemodynamics of Cardiac Tamponade

IV Fluids

Lasix

Teton 5yr old, MN, Bernese Mountain Dog

§  Pericardial effusion Confirmed with Echocardiography

§  350ml of hemorrhagic fluid removed via pericardiocentesis.

Treatment of Cardiac Tamponade

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Teton’s Diagnosis

Teton

q  No mass lesion, but one area of pericardial adhesion seen on echocardiogram.

q  Check Valley Fever Titers.

q  Consider Pericardiectomy.

5yr old, MN, Bernese Mountain Dog

Questions?