1. Interventional Management of Congenital Heart Disease

 Transcatheter occlusion of PDA's

 Gianturco coil vs. vascular occlusion devices

 Arterial vs. venous method of occlusion

 Balloon valvuloplasty

 Pulmonic stenosis

 Aortic stenosis

 Mitral / tricuspid valve stenosis

 Cor triatriatum

 Diagnostic cardiac catheterization

 Open heart surgery program

 Scheduled to begin in 2008

2. Canine Congenital Heart Disease

 Morphologic defect of the heart or great vessels that is present at birth

 Not synonymous with heritable

 Prevalence: 0.5-0.85%

 Complex deformities rare

3. Classification

 Acyanotic shunting lesion (L-R)

 Patent ductus arteriosus (PDA)

 Ventricular septal defect (VSD)

 Atrial septal defect (ASD), patent foramen ovale

 Atrioventricular canal defects

 Nonshunting lesions

 Obstructive (pressure overload)

 Aortic, subaortic stenosis (SAS)

 Pulmonic stenosis (PS)

 AV valve stenoses

 Regurgitant (volume overload)

 AV valve dysplasia

 Cyanotic shunting lesions (R-L)

 Tetralogy of Fallot

 Right to left PDA

 Eisenmenger's syndrome

 R-L VSD or ASD due to PH

 Rare congenital defects

 Cor triatriatum dexter / sinister

 Great vessel lesions

 Truncus arteriosus / pseudotruncus

 Transposition of the great arteries

4. Diagnostic Approach to CHD

 Physical examination

 Thoracic radiographs

 ECG

 Primarily useful for arrhythmia detection

 +/- chamber enlargement

 Echocardiogram

 Presence and severity of defect

 Non invasive estimation of PG across lesions/ valves

 Positive contrast echocardiography

 "Bubblegram"

 Cardiac catheterization & angiography

 Used to complete diagnostic workup

 Used prior to interventional techniques to better qualify / quantify the defect (s)

 Requires fluoroscopy

 C arm

 Used in CHD cases to obtain diagnostic information about the heart & great vessels

 Identify lesion location, quantify severity

 Angiographic studies

 Left heart: aorta, coronary arteries, LA, LV

 Right heart: Vena cava, RA, RV, pulmonary arteries

 Pressure studies: catheters can be used to measure pressures in the cardiac chambers, great vessels, pulmonary arteries and pulmonary capillaries

 "Pressure waveforms" are created

 Right heart catheterization

 Assess MPA pressure, RV, RA pressures

 Assess location and severity of PS lesion

 Assess pulmonary capillary wedge pressure (PCWP) >>> mean LA pressure

 Assess for fixed pulmonary hypertension

 (Eisenmenger's physiology)

 Assess shunting defects

 Left heart catheterization

 Assess coronary artery anatomy

 Assess/quantify shunting lesions

 Assess LV and aortic pressures

5. Indications for Cardiac Catheterization in CHD

 Assessment of valve and chamber anatomy

 Diagnostic and therapeutic catheterization

 Balloon dilation

 Device placement

 Coronary angiograms: coronary artery anomalies

 Shunt detection and quantification prior to intervention

 Oximetry (quantitative)

 Angiography (qualitative)

 Therapeutic cardiac catheterization

 Therapeutic intervention: Successful management of cardiac disease through a minimally invasive approach

 Balloon valvuloplasty

 PDA transcatheter occlusion

 Septal defect closure ??

6. Cardiac Catheterization: Complications

 Arrhythmias

 Intracardiac damage/perforation

 Blood clots in the catheter

 Artery or vein damage

 Hematoma, hemorrhage at incision site

 Angiograms: Excessive contrast use

7. Patent Ductus Arteriosus

 Signalment and presentation

 Puppy to young adult

 Female > male

 Predisposed breeds

 Asymptomatic if small PDA

 Large shunt: clinical signs of LCHF

 Reversed PDA (right to left shunting PDA)

 Weakness, cyanosis

 Physical exam

 Left basilar continuous murmur

 +/- bounding pulses ("waterhammer")

 Due to diastolic "run off" causing increased pulse pressure

 Clinical sequelae: Dependant on shunt size

 Left sided CHF

 Irreversible myocardial failure

 Reversal: right to left shunt

 Diagnostics: Radiographs

 LA and LV enlargement

 Aortic ductal aneurysm and MPA bulge

 Pulmonary overcirculation

 ECG: Tall R waves

 Echocardiogram

 LA/LV volume overload +/- myocardial failure

 PDA visualization: anatomy and flow

 Medical management: Short term

 Furosemide

 ACE inhibitor

 Surgical ligation

 Transcatheter occlusion: Device options: Gianturco coil, VOD, ACDO

 Transcatheter occlusion--Complications

 <1% mortality

 Hemorrhage

 Perforation of the aorta

 Damage to peripheral vessel

 Coil embolization

 Pulmonary artery (pulmonary hypertension may result)

 Lungs

 Aorta (celiac / mesenteric arteries)

 Residual flow

 Hemoglobinuria (transient)

 2nd procedure

 VMTH: <4%

 Medical treatment for longstanding PDA

 Manage CHF: diuretics, ACEI

 Atrial fibrillation: digoxin +/- diltiazem

 Myocardial failure: Older patients or patients with large shunts that have been overlooked

 Pimobendan therapy: Stabilizes patient, improves outcome long term for chronic PDA cases

 Goals: PDA closure !!!!

 Reduce volume overload, wean off diuretics

 +/- continue Pimobendan and antiarrhythmics

8. Subaortic Stenosis (SAS)

 Discrete, fixed fibrous or fibromuscular ridge or ring of tissue

 Subvalvular

 Valvular AS uncommon

 Fixed outflow tract stenosis

 LV concentric hypertrophy

 Coronary lesions

 Myocardial fibrosis

 Ventricular arrhythmias

 Diastolic dysfunction

 Large breed dogs

 Likely heritable

 Progressive lesion for first 12 months

 PE: left basilar systolic ejection murmur

 "Pulsus parvus et tardus"

 Arrhythmia

 Clinical signs / sequelae

 Exercise intolerance

 Arrhythmias

 Collapse /syncope

 Sudden death

 Left sided CHF ( esp. if concurrent MVD)

 Valvular endocarditis

 Diagnostics

 Thoracic radiographs: Variable

 ECG: Tall R waves, arrhythmias

 Echocardiogram

 Current treatment options

 Cardiac catheterization rarely used: further diagnostic information

 Surgical management: variable effectiveness

 Open heart resection: requires CPB

 Septal myectomy

 Alcohol ablation of septal hypertrophy

 Balloon dilation of stenosis

 Acute hemodynamic improvement

 Questionable reduced risk of sudden death

 No clear benefit over medical management

 Medical management

 Beta blockade: Atenolol therapy

 Antiarrhythmics, Diuretics, ACEI PRN

 Prophylactic Abs

9. Pulmonic Stenosis (PS)

 Signalment and presentation

 Small breed dogs

 Often asymptomatic

 CS: exercise intolerance / collapse

 Obstructive lesion / stenosis

 Secondary RV concentric hypertrophy

 Valvular, supravalvular , subvalvular

 PE: Left basilar systolic murmur

 Normal femoral pulses

 +/- jugular pulses, arrhythmia

 Clinical signs / sequelae

 Exercise intolerance

 Syncope

 Ventricular arrhythmias

 Atrial fibrillation

 Right sided congestive failure

 Cyanosis if R-L shunt present

 Rarely sudden death

 Diagnostics

 Thoracic radiographs: MPA bulge, reverse "D"

 ECG: Deep S waves

 Echocardiogram

 "Bubblegram" : assess for R-L shunt

 Interventional management: Cardiac catheterization

 Angiographic evaluation of pulmonic valve anatomy/lesion

 Obtain pressure waveforms

 +/- coronary angiography

 Balloon valvuloplasty

 Moderate /severe valvular PS

 If ASD or PFO present

 If significant TR present

 PS: Complications

 Variable pulmonic insufficiency

 Transient or permanent RBBB

 Transient arrhythmias

 Cardiac perforation

 Significant tricuspid valve damage

 Other management options: Dysplastic, hypoplastic valves

 Surgery via "inflow occlusion"

 Valvulotomy

 Patch graft technique

 RV to PA conduit

 Medical management : Beta blocker

 Symptomatic treatment for CHF if present

 Antiarrhythmic therapy PRN

10. Atrioventricular Valve Dysplasia

 Mitral valve dysplasia (MVD)

 Regurgitation >> Stenosis

 Bull terriers ( mitral stenosis)

 Large breed dogs

 Tricuspid valve dysplasia (TVD)

 Regurgitation >> stenosis

 Labrador Retrievers

 German Shepherds, Golden Retrievers

 Likely heritable

 Physical examination

 MVD: left apical systolic +/- diastolic heart murmur

 C/S of left sided CHF

 TVD: right apical systolic +/- diastolic heart murmur

 C/S of right sided CHF

 Both MVD and TVD

 Variable exercise intolerance +/- syncope

 Due to low cardiac output (associated with valvular stenosis or tacharrhythmias)

 Diagnostics

 Thoracic radiographs: Variable

 ECG : Atrial arrhythmias common

 Echocardiogram: Definitive diagnosis

 AVV Dysplasia: Options for management

 Balloon dilation of stenotic valve

 Surgery

 Inflow occlusion and valvulotomy for TVD

 MVD or TVD: CPB and valve repair/replacement

 Only mature dogs >10kg

 Expense

 Limited surgical experience

 Lifelong anticoagulant therapy

 Medical: Tx CHF and atrial dysrhythmias

 Diuretic, ACEI

 Antiarrhythmics: rate control

 Pimobendan therapy: improve cardiac output

11. Left to Right Shunts

 Direction and magnitude of shunt

 Size of communication

 Relative resistance to flow downstream

 Most common: PDA ( as described above ) , VSD, ASD

 VSD: Clinical presentation: Dependant on VSD size

 Restrictive (small): asymptomatic

 Nonrestrictive: LA/LV volume overload causing symptoms of left sided CHF

 Physical examination

 Right sided systolic ejection murmur

 +/- weak arterial pulses

 VSD: Pathophysiology: Determination of degree of shunting

 Diagnostics

 Thoracic radiographs : Pulmonary overcirculation

 ECG

 Echocardiogram: Visualize defect and degree of volume overload

 Interventional and medical management

 Tx for left sided CHF: diuretics, ACEI

 Tx atrial dysrhythmias

 Surgical management

 MPA banding (palliative)

 Open heart repair

 Interventional management

 Future of closure with Amplatzer devices

 Primary difficulty: relation of VSD to aortic valve

 Atrial septal defect (ASD)

 Usually clinically insignificant

 Most patients are asymptomatic

 Exceptions include: large ASD's, R-L shunts, and AV canal defects

 L-R shunts

 Soft left basilar systolic ejection murmur

 Variable left heart volume overload

 R-L shunts

 Occur with pulmonic stenosis or PH

 Interventional and medical management

 Medical management of L CHF

 Intervention: ASD closure

 Amplatzer device

 Surgical closure via suture or patch

12. Right to Left Shunts

 Most common: Tetralogy of Fallot, R-L PDA

 Eisenmenger's Physiology: Large, nonrestrictive VSD (Large PDA, ASD or AV canal) leading to irreversible pulmonary hypertension

 Clinical presentation

 Moderate to severe exercise intolerance

 Cyanosis

 Stunted growth

 Physical exam

 Tetralogy of Fallot: left basilar systolic murmur due to PS

 Eisenmenger's patients: no heart murmur

 Diagnosis via contrast echocardiogram : aka: "Bubblegram"

 R-L shunting defects: Options for management

 Surgical repair of Tetralogy of Fallot (rare)

 Palliative shunt (T of F)

 Redirect blood from left subclavian into pulmonary artery (Blalock-Taussig shunt)

 Balloon dilation of pulmonic stenosis (T of F)

 May create large L-R shunt and CHF

 Medical management

 Phlebotomy with IV fluid replacement

 Hydroxyurea

 Sildenafil (Viagra)

 +/- beta blockers

13. Cor Triatriatum Dexter

 Congenital lesion: partitioning of the right atrium into two chambers by a fibromuscular membrane

 Clinical signs of RHF at very young age

 Echocardiographic diagnosis

 Cardiac catheterization: Right heart: locate defect, obtain pressure tracings

 Angiogram: Location of membrane and perforation

 Cor Triatriatum Dexter: Management

 Long term medical management

 Diuretics and frequent abdominocentesis

 Unrewarding, progressive RHF

 Surgical management: Invasive

 Thoracotomy

 Requires inflow occlusion

 Balloon dilation via cardiac catheterization

 Variable to good success

 May need to repeat procedure

Future Possibilities...