What’s your purpose? “It may be that your sole purpose in life is simply to serve as a warning to others.” -Anonymous
DISEASES OF THE CARDIOVASCULAR SYSTEM: Cardiomyopathies CHF Valvular disease Cogenital malformation Infectious
CONGENITAL DEFECTS: PULMONIC STENOSIS Beagles, bulldogs (both French and English), boxers, Bull Mastiffs, Miniature Schnauzers, Chihuahuas and various terrier breeds are predisposed to pulmonic stenosis. CAUSE: ____________________________ inheritance > 1 year
PULMONIC STENOSIS ________most common congenital heart disease in dogs In pulmonic stenosis, the right ventricular outflow tract is narrowed, either at the valve itself, just below it, or just after it.
PULMONIC STENOSIS The most common form of pulmonic stenosis involves a deformed pulmonary valve such that the valve leaflets are too thick, the opening is too narrow, or the valve cusps are fused. The heart must pump extra hard to get blood through This unusually narrow, stiff valve. The right ventricle becomes _________________ from all this extra work. The right atrium, May become dilated and hypertrophied.
CONGENITAL DEFECTS: PULMONIC STENOSIS NORMAL CANINE CHEST RADS THIS DOG HAS PULMONIC STENOSIS – THE HEART LOOKS “PREGNANT” IN THE FRONT DUE TO ______________ VENTRICULAR ENLARGEMENT
CONGENITAL DEFECTS: PULMONIC STENOSIS • CLINICAL SIGNS: • Syncope • Tiring on exercise • _____________ -sided congested heart failure • Left basilar (base) murmur (PAM) • Right ventricular enlargement • Radiographs: right ventricular enlargement, dilation of the pulmonary artery, pulmonary underperfusion • Echo: right ventricular hypertrophy and enlargement, dilation of the main pulmonary artery (prominent jugular pulse)
PULMONIC STENOSIS: TREATMENT A special balloon is inserted into the valve where it is inflated and the obstruction is broken down: ___________________________________ Unfortunately, medical management is not very beneficial in these cases. Beta-blockers may be used to relax the heart muscle and possibly dilate the stenosis.
CLIENT EDUCATION • Do not breeding • Mild - moderate pulmonic stenosis: better prognosis • Moderate - severe pulmonic stenosis: __________________ prognosis
CONGENITAL DEFECTS: SUBAORTIC STENOSIS Newfoundland, Boxer, Golden Retriever, and Bull Terrier are most commonly affected LESION DEVELOPS IN THE FIRST 4-8 WEEKS OF LIFE: thickening Endocardial tissue
CONGENITAL DEFECTS: SUBAORTIC STENOSIS • There is a scar-like narrowing just below the aortic valve. The heart must pump extra hard to get blood through the narrowed area. The blood is pushed through in a turbulent fashion creating a heart murmur.
CONGENITAL DEFECTS: SUBAORTIC STENOSIS THE HARD WORK RESULTS IN LEFT__________________________________ , LEFT ATRIAL ENLARGEMENT, AORTIC DILATION: _______________________
CONGENITAL DEFECTS: SUBAORTIC STENOSIS: • CLINICAL SIGNS: • Fatigue • Exercise intolerance (low cardiac output) • ____________________________ • Systolic murmur (soft – moderate) at the left heart base • ECG: evidence of left ventricular enlargement - ↑ QRS height • Echo: left ventricular hypertrophy, subvalvular fibrous ring, aortic dilation
CONGENITIAL DEFECTS: SUBAORTIC STENOSIS • TREATMENT • Balloon catheter dilation – has been done with variable and temporary results • Medical management: THE GOAL IS TO SLOW THE HEART RATE AND DECREASE CONTRACTILITY; PROPRANOLOL (BETA-BLOCKER WILL DO THIS)
CONGENITAL DEFECTS: SUBAORTIC STENOSIS • CLIENT INFO: • Should not be used for breeding • Acute, left-sided congestive heart failure is possible • Sudden death is not uncommon
CONGENITAL DEFECTS: TETRALOGY OF FALLOT Keeshonds are the most commonly affected breed, but bulldogs and cats have increased incidence as well. Cause: polygenic inheritance
CONGENITAL DEFECTS: TETRALOGY OF FALLOT • THERE ARE 4 MAIN ANATOMICAL ABNORMALITIES IN THIS DISEASE! • Pulmonic stenosis • ______________________________ • Ventricular septal defect • Overriding aorta
Right to left shunt: pulmonary and systemic circulations
Overiding aorta: Blood from RV into aorta: mixed blood, not fully oxygenated blood. Body stimulates more RBC production to stimulate oxygen carrying capacity
CONGENITAL DEFECTS: TETRALOGY OF FALLOT • CLINICAL SIGNS and DIAGNOSIS: • Affected puppies are smaller than littermates • Exercise intolerance • Dyspnea, tachypnea • Syncope • Cyanosis • ______________________:occurs as a response to the large amount of deoxygenated blood going to the systemic circulation • Systolic murmur over the pulmonic area • ECHO: right ventricular hypertrophy, subaortic ventricular septal defect, right outflow tract obstruction
CONGENITAL DEFECTS: TETRALOGY OF FALLOT • TREATMENT: • Phlebotomy: to keep PCV below __________ (replace with crystalloids) • Surgery: • Create a left–to–right shunt by doing systemic artery to pulmonary artery anastamosis • Complete correction requires cardiopulmonary bypass which is uncommon in animals
CONGENITAL DEFECTS: TETRALOGY OF FALLOT • CLIENT INFO: • These dogs should not be ___________ • Congestive heart failure rarely develops • Affected animals need regular phlebotomy • Limit stress and exercise • Caution when using sedatives/ tranquilizers
CONGENITAL DEFECTS: PERSISTENT RIGHT 4TH AORTIC ARCH Great Danes, German Shepherds, Irish Setters are most commonly affected
CONGENITAL DEFECTS: PERSISTENT RIGHT 4TH AORTIC ARCH Constrict the esophagus , food cannot get pass and ________________will be formed.
CONGENITAL DEFECTS: PERSISTENT RIGHT 4TH AORTIC ARCH Main cause of megaesophagus in puppies: dyspnea and weight loss. Clinical signs include regurgitation due to megaesophagus, aspiration pneumonia, dyspnea, weight loss
PERSISTENT RIGHT 4TH AORTIC ARCH • Dx: Barium swallow study • Tx: Surgery (like PDA); megaesophagus maintenance; Ab’s for secondary infections • Client informations • Do not breed • Sx is needed • After sx some megaesophagus hence no boluses of food
Cases • Four-month-old female toy poodle weighing 2.2 kg ("Cindy") • Six-month-old female spayed Domestic Shorthair cat ("Nimbus")
References • Alleice Summers, Common Diseases of Companion Animals • http://veterinarynews.dvm360.com/dvm/article/articleDetail.jsp?id=156665 • VIN: Robert Prosek DVM, MS, DACVIM-Cardiology, DECVIM-CA • Echocardiography in the Dog, Cat and Horse: Dr. Francesco Porciello, 2009 • http://www.vin.com/WebLink.plx?URL=http://www.vmth.ucdavis.edu/cardio/cases/