Transcript diseases of the cardiovascular system

DISEASES OF THE
CARDIOVASCULAR SYSTEM:
Cardiomyopathies
Cogenital malformation
CHF
Acquired Valvular disease
Infectious
CHRONIC MITRAL VALVE
INSUFFECIENCY
SMALL BREED/TOY BREED DOGS, USUASLLY OLDER THAN 10 YEARS
THE PREVALENCE OF THIS DISEASE INCREASES WITH AGE, AND IS
PROGRESSIVE. IT ACCOUNTS FOR ~95% OF ALL HEART FAILURE CASES
CHRONIC MITRAL VALVE
INSUFFICIENCY
ONE OF THE MOST COMMON
CAUSES IS CHRONIC PERIODONTAL
DISEASE!
BACTERIA THAT LIVE IN TARTAR,
GET SHOWERED INTO THE BLOOD
STREAM AND COLONIZE IN THE
VALVE LEAFLETS.
CHRONIC MITRAL VALVE INSUFFICIENCY
CHRONIC PERIODONTAL DISEASE CAN AFFECT SEVERAL ORGAN SYSTEMS
1.Lungs: Pulmonary fibrosis, bronchitis,
and chronic obstructive pulmonary
disease.
2.Heart: Endocarditis, mitral valve
regurgitation, and myocardial
degeneration.
3.Liver: Hepatic parenchymal
inflammation and hepatopathy.
4.Kidneys: Interstitial nephritis and
glomerulonephritis.
MITRAL VALVE INSUFFICIENCY
THIS IS THE OPEN LEFT
VENTRICLE SHOWING THE
MITRAL VALVE LEAFLETS.
WHAT ARE THE STRING-LIKE
STRUCTURES THAT ATTACH
THE VALVES TO THE
PAPILLARY MUSCLES?
MITRAL VALVE INSUFFICIENCY
CHORDAE TENDINEAE
MITRAL VALVE INSUFFICIENCY
TOP LEAFLET IS NORMAL
BOTTOM LEAFLET IS
THICKENED AND NODULAR. THIS
IS DUE TO INCREASED
FIBROBLASTIC TISSUE WITHIN
THE VALVE LEAFLETS
L HR
CHRONIC MITRAL VALVE INSUFFICIENCY
THE STIFF MALFORMED VALVE
FAILS TO CLOSE SUFFICIENTLY
DURING SYSTOLE.
DURING LEFT VENTRICULAR
CONTRACTION, BLOOD FLOWS
BACK INTO THE LEFT ATRIUM
MITRAL VALVE INSUFFICIENCY
IF BLOOD CONTIUES THIS BACKWARD
FLOW, THE ANIMAL MAY EXPERIENCE
LEFT-SIDED HEART FAILURE
CHARACTERIZED BY PULMONARY
EDEMA
CHRONIC MITRAL VALVE INSUFFICIENCY
• DIAGNOSIS:
– Radiographs
– Echo
– Systolic murmur at left apex; “whooping” quality
• There is no treatment to delay the onset of clinical
signs. Treatment is aimed at improving symptoms
of heart failure
– Diuretics (lasix)
– Enalapril (avoids retention of fluid): ACE inhibitor,
vasodilator
– Pimobendan: Helps pump blood efficiently
– Diet change: low sodium
TRICUSPID VALVE
INSUFFICIENCY
TRICUSPID VALVE INSUFFICIENCY
TRICUSPID INSUFFICIENCY RESULTS
IN RIGHT-SIDED HEART FAILURE
CHARACTERIZED BY PLEURAL
EFFUSION
TRICUSPID VALVE INSUFFICIENCY
Ascites. Blood backs up in vena cava
and this back up causes back overload,
liver overloaded with fluids. Vascular
permeability, leaky vessels.
RIGHT-SIDED HEART FAILURE ALSO
LEADS TO pleural effusion and
ASCITES
NOTE: THE LOSS OF ABDOMINAL
DETAIL
TRICUSPID VALVE
INSUFFICIENCY
• Treatment and client info are the same as for
mtiral insufficiency; repeated
abdominocentesis may be needed in these
cases.
• Lasix: Diuretics
• Enalapril: Reduces retention of fluids
LIVE LIFE TO THE FULLEST!
“You only live once, but if you
work it right, once is enough.”
-Joe E. Lewis, comedian
DISEASES OF THE
CARDIOVASCULAR SYSTEM:
Cardiomyopathies
Cogenital malformation
CHF
Acquired Valvular disease
Infectious
DISEASES OF THE
CARDIOVASCULAR SYSTEM
HEARTWORM DISEASE
CATS HWD
DISTRIBUTION OF CANINE
HEARTWORM DISEASE
CANINE HEARTWORM DISEASE
• PARASITE CAUSING HEARTWORM
DISEASE: DIROFILARIA IMMITIS
MICROFILARIA OF D. IMMITIS
ADULT HEARTWORMS
CANINE HEARTWORM DISEASE
Mosquito transmits
L3 stage.
L1 – L3 develops in
the mosquito.
Dog mff goes to
mosquito.
Dog L3 – L5
ONLY FEMALE MOSQUITOES BITE
CANINE HEARTWORM DISEASE
Intermediate host
Definitive host
CANINE HEARTWORM DISEASE
ADULT HEARTWORMS LIVE
IN THE PULMONARY
ARTERIES. THE HEART MUST
WORK EXTRA HARD TO PUMP
AGAINST THIS OBSTRUCTION.
ADULT HEARTWORMS IN
RIGHT VENTRICLE AND
PULMONARY ARTERY
CANINE HEARTWORM DISEASE
• PREDOMINANT PATHOLOGY: DAMAGE TO THE
PULMONARY ARTERY FROM ADULT HEARTWORMS
– Endothelial damage and sloughing
– Inflammation (leukocytes, platelets)
• Risk of thromboemboli
– Pulmonary hypertension
– Disruption of vascular integrity
• Thickened, fibrosed
• RIGHT VENTRICULAR HYPERTROPHY AND
RIGHT-SIDED HEART FAILURE
– The right ventricle compensates by dilating and increasing
muscle thickness
– Ultimately, there is decompensation and heart failure
GRADING
• Class 1: No symptoms or mild symptoms such as an occasional
cough.
• Class 2: Mild to moderate symptoms such as an occasional cough
and tiredness after moderate activity.
• Class 3: General loss of body condition, a persistent cough, and
tiredness after mild activity. Trouble breathing and signs of heart
failure are common. For class 2 and 3 heartworm disease, heart and
lung changes are usually seen on chest x-rays.
• Class 4: Caval syndrome. There is such a heavy worm burden that
blood flowing back to the heart is physically blocked by a large mass
of worms. Caval syndrome is life-threatening and quick surgical
removal of the heartworms is the only treatment option. The surgery
is risky, and even with surgery, most dogs with caval syndrome die.
• The yellow arrows point to the tortuous and severely enlarged
pulmonary arteries.
• There is a mild increase in the size of the right atrium.
• The pulmonary parenchyma also has a slight interstitial pattern.
CANINE HEARTWORM DISEASE
• Severe infection can lead to CAVAL
SYNDROME
– Worms back up into the right atrium and venae
cavae
• Found in heavy worm burdens (>60)
• Associated with a poor prognosis
• Surgical treatment: pull worms from the right heart and
venae cavae via jugular venotomy
Heartworm embolectomy procedure.
Basket forceps placed throught he right jugular vein and into the right heart were
used to retrieve the heartworms from this Rottweiler with caval syndrome.
CANINE HEARTWORM DISEASE
IDEXX SNAP TEST
ADULT FEMALE ANTIGEN
CANINE HEARTWORM DISEASE
CANINE HEARTWORM DISEASE
CANINE HEARTWORM DISEASE:
PREVENTION
• HEARTGARD/IVERHEART
– Ivermectin/pyrantel pamoate
• INTERCEPTOR/SENTINEL
– Milbemycin oxime
• REVOLUTION
– Selamectin
• ADVANTAGE MULTI/PROHEART 6
– Moxidectin
– Q 6 month injectable
CANINE HEARTWORM DISEASE:
TREATMENT
STANDARD PROTOCOL: 1 epaxial injection, followed
By a second injection on the opposite side 24 hours later
ALTERNATIVE PROTOCOL: 1 Injection given followed in
4-6 weeks by 2 injections given 24 hours apart
ONLY KILLS ADULT (L5) STAGE WORMS; DOXYCYCLINE IS REC. AS
COMPLIMENTARY TX (WOLBACHIA)
•
•
•
•
•
Heartworm Treatment – Slow Kill Method – VTI
Team: Dr. B, Dr. Dev, Miss Kennar, Miss Foitnik
Doxycycline: 5 – 10 mg/ kg (SID or BID)
Prednisone: 1 mg/kg : BID X 7 days; SID X 7 days, EOD X 7 days
DAY 1
– Buprenex: 0.015 mg/ kg OR Tramadol: 1mg/lb BID X 3 days PO before
melarsomine injection
– Famotidine 0.5 mg/kg SQ: before melarsomine injection
– Melarsormine: 0.1 mls/ kg IM
DAY 30
– Buprenex: 0.015 mg/ kg OR Tramadol: 1mg/lb BID X 3 days PO before
melarsomine injection;
– Famotidine 0.5 mg/kg SQ: before melarsomine injection
– Melarsormine: 0.1 mls/ kg IM
DAY 31
– Buprenex: 0.015 mg/ kg OR Tramadol: 1mg/lb BID X 3 days PO before
melarsomine injection;
– Famotidine 0.5 mg/kg SQ: before melarsomine injection
– Melarsormine: 0.1 mls/ kg IM
THANK YOU ROYALS 2011
References
• Alleice Summers, Common Diseases of
Companion Animals
• http://veterinarynews.dvm360.com/dvm/article
/articleDetail.jsp?id=156665
• VIN: Robert Prosek DVM, MS, DACVIMCardiology, 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/
References
• http://cardiology.vetmed.lsu.edu/Education/Ac
quiredCardiacDiseases/HeartwormDisease/tabi
d/448/Default.aspx
• http://www.heartwormsociety.org/