To understand the heart and mind of a person, look not at what he has already achieved,

but at what he aspires to

-Kahlil Gibran

•http://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/winter2007/learning.shtml#fig1

VC > RA > Triscuspid valve > RV > Pulmonary valve: pulmonary a. >Lungs > pulmonary v. > LA > Mitral v. > LV > Aortic v. > Aorta > SYSTEMIC CIRCULATION > VC

CARDIAC CYCLE• The atria contract in unison and the ventricles contract in unison

• The atria and ventricles ___________ contract at the same time (as one group contracts, the other relaxes)

• ATRIAL contraction sends blood into the ventricles through the _________ and _______________ valves

– While this is occurring, the __________________ valves close

– The ventricles relax at this time 

• VENTRICULAR contraction sends blood through the _______________ valves into the aorta and pulmonary artery

– While this is occurring, the bicuspid and tricuspid valves close

– The atria ___________ at this time and blood enters the atria from the vena cava and pulmonary veins

• SYSTOLE – ________________ of the atria and ventricles

– blood is being _________________ from the heart

• DIASTOLE – _______________ of the atria and ventricles -heart is filling with blood

HEARTBEAT: Lub-dub: S1 and S2

– S1: Beginning of systole (pulse)

• increase in _________________pressure during contraction exceeds the pressure within the atria

• closing ____valves (mitral first)

• contraction forces blood semilunar valves.

– S2: Beginning of _________ (no pulse)

• ventricles begin to ___________

• pressures within the heart become ________ than the semilunar valves,

• causes the semilunar valves to snap _________ (aortic first)

STROKE VOLUME

• Contractility:  Contractility is the intrinsic ability of cardiac muscle to develop force for a given muscle length.  It is also referred to as inotropism.

• Preload:  Preload is the muscle length prior to contractility, and it is dependent of ventricular filling (or end diastolic volume.)  This value is related to right atrial pressure.  The most important determining factor for preload is venous return.

• Afterload:  Afterload is the tension (or the arterial pressure) against which the ventricle must contract.  If arterial pressure increases, afterload also increases. Afterload for the left ventricle is determined by aortic pressure, afterload for the right ventricle is determined by pulmonary artery pressure.      

NORMAL CANINE HEART

CANINE WITH CARDIOMEGALY

2.5 – 3.5 rib spaces

Stroke Volume (SV) = EDV – ESVCardiac Output (Q) = ____ X ______

MURMURS• I - Lowest intensity, difficult to hear even by expert

listeners

• II- Low intensity, but usually audible by all listeners

• III - Medium intensity, easy to hear even by inexperienced listeners, but without a _________thrill

• IV - Medium intensity with a palpable thrill

• V - Loud intensity with a palpable thrill. Audible even with the stethoscope placed on the ________ with the edge of the diaphragm

• VI - Loudest intensity with a palpable thrill. Audible even with the stethoscope ___________ the chest.

DISEASES OF THE CARDIOVASCULAR SYSTEM:

CardiomyopathiesCHF

Valvular diseaseCongenital malformation

Infectious

FELINE HYPERTROPHIC CARDIOMYOPATHY (HCM)

NEUTERED MALE CATS BETWEEN 1-16 YRS. OF AGE

THE MOST COMMON CARDIOMYOPATHY IN ________!

FELINE HYPERTROPHIC CARDIOMYOPATHY

• THE PREDOMINANT PATHOLOGY OF THIS DISEASE IS ____________________ HYPERTROPHY

• CAUSE: – +/- genetics

– related to abnormal ___________________ or ________________ transport within the muscles of the heart

FELINE HYPERTROPHIC CARDIOMYOPATHY

Blood backs up LA enlarged

FELINE HYPERTROPHIC CARDIOMYOPATHY: DIAGNOSIS

http://www.youtube.com/watch?v=yNj-lQaUBao

http://www.youtube.com/watch?v=KvUFb4qZwmw&feature=related

http://www.youtube.com/watch?v=xlsq5tJpj04&feature=related

FELINE HYPERTROPHIC CARDIOMYOPATHY: Pathophysiology

PROBLEM #1: The walls lose compliance and resist filling during diastole! (_________________________)

FELINE HYPERTROPHIC CARDIOMYOPATHY: Pathophysiology

• PROBLEM #2: If the left ventricle cannot fill adequately with blood, the blood backs up into the left atrium (enlargement) → pulmonary veins → ___________________!

• PROBLEM #3: The left atrium becomes dilated with blood → the blood becomes __________→ blood stasis leads to clot formation → clot becomes dislodged and trapped elsewhere in the arterial system → _____________________!

***90% of thrombi become lodged in the aortic ___________causing “saddle thrombus”***

FELINE HYPERTROPHIC CARDIOMYOPATHY: SADDLE THROMBUS

ACUTE, PAINFUL CONDITION CAUSINGPARESIS, ___________ REAR LEGS/FEET!

FELINE HYPERTROPHIC CARDIOMYOPATHY: SADDLE THROMBUS

FELINE HYPERTROPHIC CARDIOMYOPATHY: CLINICAL SIGNS and

DIAGNOSIS

• Soft, sytolic murmur (grade 2-3/6)• Gallop rhythms or other arrhythmias

– ECG: ↑ p wave duration, ↑ QRS width, sinus tachycardia• Echo: shows ↑ ventricular wall thickness, dilated left

atrium• _____________ onset of heart failure• Acute onset of systemic

__________________________– Hindlimb paresis– Cold rear legs– Painful rear legs

FELINE HYPERTROPHIC CARDIOMYOPATHY: TREATMENT

OR

PROPRANOLOL (B-BLOCKER)__________________________

DILTIAZEM (CALCIUM CHANNEL BLOCKER) Inhibits contractility: low BP and cardiac ________

FUROSEMIDE (DIURETIC)

ANTICOAGULANT

ASPIRIN

Relax so Time tofill

FELINE HYPERTROPHIC CARDIOMYOPATHY: TREATEMENT

• LASIX (furosemide): a diuretic used to treat ___________________

• DILTIAZEM: a calcium channel blocker used to inhibit cardiac and vascular smooth muscle ____________; reduces blood pressure and cardiac afterload; overall improvement in ______________– Or Propranolol: a beta-blocker to decrease heart rate and

myocardial oxygen demand• ASPIRIN: an anticoagulant used to thin blood and

help prevent __________ formation in HCM• TPA (Activase): serves as a ____________ resulting

in the breakdown of clots that have already formed– Or Heparin, Warfarin: acts on the coagulation factors to

inhibit the formation of a stable clot

FELINE HYPERTROPHIC CARDIOMYOPATHY: CLIENT INFO

• There is no ____________!– Cats with HCM may experience heart failure,

arterial embolism, or SUDDEN DEATH!

– Cats whose heart rates stay below 200 beats/min have a better prognosis than those whose heart rate is >200 beats/min

CANINE HYPERTROPHIC CARDIOMYOPATHY:

• An _____________ canine disease, but the cause appears to be heritable

• CLINICAL SIGNS:– Fatigue– Sudden death– Tachypnea– Syncope– Cough

• BREEDS: German Shepherds, Rottweilers, Cocker Spaniels, and others

DISEASES OF THE CARDIOVASCULAR SYSTEM:

CardiomyopathiesCHF

Valvular diseaseCongenital malformation

Infectious

CONGENITAL DEFECTS: PATENT DUCTUS ARTERIOSUS

CHIHUAHUAS, MALTESE, POODLE, POMERANIAN, SHELTIE PUPPIES COMMONLY AFFECTED (Table 1-1)

CONGENITAL DEFECTS: PATENT DUCTUS ARTERIOSUS

Normally, the ductus arteriosus carries blood from the _______________ to the _________ during fetal development. It bypasses the lungs of the fetus.

CONGENITAL DEFECTS: PATENT DUCTUS ARTERIOSUS

The duct should close in the first 12-24 hours after birth. If it does not, the blood begins to shunt from the aorta into the pulmonary artery and _______________ the lungs.The left side of the heart will have an increase in blood return and become volume overloaded.________________________

THIS IS CALLED A ___________________SHUNT

CONGENITAL DEFECTS: PATENT DUCTUS ARTERIOSUS (PDA)

CONGENITAL DEFECTS: PATENT DUCTUS ARTERIOSUS

• CLINICAL SIGNS:– A loud murmur best heard over the left base– Sometimes called a “machinery” murmur or a continuous

murmur (btw S1 and S2)– If the shunt is small some animals may be asymptomatic– In large shunts the animal will develop

____________________• Pulmonary edema• Cough• Exercise intolerance• Tachypnea• Weight loss

– ECG: wide range of arrhythmias including APCs and VPCs– Echocardiography (ultrasound)– Radiographs: _____________ and ventricular enlargement

PATENT DUCTUS ARTERIOSUS: TREATMENT

EXCELLENT _____________ WITH SURGICAL CORRECTION: LIGATION OF THE DUCTUS ARTERIOSUS

PATENT DUCTUS ARTERIOSUS: TREATMENT

• CLIENT INFO:– 64% OF ANIMALS WILL DIE WITHIN _____

YEAR IF NOT TREATED SURGICALLY

– Dogs with this condition should not be used for _______________

ATRIAL AND VENTRICULAR SEPTAL DEFECTS~ Cats

During fetal life, the _____________________ is an openingi n the interatrial septum, allowing shunting of blood from the right atrium to the left atrium in order to bypass the nonfunctioning fetal lungs. It should close at birth. If it doesn’t, after birth, the blood will shunt from left to right resulting in overload of the right side of the heart.

Atrial Septal Defect

CONGENITAL DEFECTS: ATRIAL AND VENTRICULAR SEPTAL DEFECTS

• CLINICAL SIGNS: ATRIAL SEPTAL DEFECTS– Result in overload of the right side of the heart

→ dilation and hypertrophy of the right-sided chambers

– Systolic murmur– _____________________ failure– Radiographs: right ventricular enlargement– Echo: right ventricular dilatation

CONGENITAL DEFECTS: ATRIAL AND VENTRICULAR SEPTAL DEFECTS

Blood is shunted from the oxygen-rich left ventricle into the right ventricle. The blood goes through pulmonary circulation and right back into the left atrium and ventricleresulting in volume overload of the left side of the heart. The right ventricle may dilate as well.

CONGENITAL DEFECTS: ATRIAL AND VENTRICULAR SEPTAL DEFECTS

• CLINICAL SIGNS: VENTRICULAR SEPTAL DEFECTS:– Animals with small defects may have minimal or no signs– Larger defects may result in acute ________________ ,

usually by 8 weeks of age– A harsh holosystolic murmur

• CLIENT INFO:– Repair of these defects requires open-heart surgery or

cardiopulmonary bypass. These procedures are uncommon in the dog and cat

– Most of these animals will eventually experience development of congestive heart failure

VSD - Treatment

• There are 2 current surgical options available.  – Before right-to-left shunting has developed,

__________________________• decrease the blood flow across the defect

• reducing the overload on the lungs and the left heart. 

– Repair of the defect, but this requires open heart surgery and carries a high risk.