Cardiology Basics

1. Cardiology Basics: At The heart of the matter Jason M . Chin, DVM Oradell Animal Hospital

2. Why is the heart so important? It pumps blood to organs to provide: Oxygen Nutrients Removes waste ( biproducts of metabolism) Provides means for signaling/communication

3. Perfusion Determined by Cardiac Output: CO = SV x HR SV = Preload x Contractility Afterload Why are these important to think about?

4. A & P

5. A & P

6. A & P – Electrical Conduction Basic Pathway: SA node to AV node to Bundle of His/Purkinje fibers (ventricles)

7. A & P – Electrical Conduction Systole : The ‘active’, contraction phase of the heart cycle Diastole : The ‘relaxed’, filling phase of the heart cycle

8. A & P – Electrical Conduction

9. The Physical Exam History : As important as any physical parameter Syncope Exercise intolerance Difficulty/Labored breathing Weight loss ( cachexia ) Observation : What does your patient look like? Dyspnea Coughing Weak Abduction of elbows/Extended head Cheek puffing/Open mouth breathing

10. Dyspnea http://www.youtube.com/watch?v=aqWiWlKv7OE

11. Dyspnea http://www.youtube.com/watch?v=Zp7CiC7SXjk

12. PE – Vital Parameters http://www.cvmbs.colostate.edu/clinsci/wing/firstaid/vital.htm Dog Cat Heart Rate 70-160 bpm 160-240 bpm Respiratory Rate 10-30 bpm 20-30 bpm Temperature 100.0 – 102.5 F 100.0 – 102.5 F

13. PE – Vital Parameters Pulses Strong and Synchronous Mucus Membranes Pink and Moist CRT < 2s

14. PE - Auscultation Cardiac : Murmurs Arrhythmias Pulmonary : Crackles ( rales ) Wheezes ( rhonchi ) r/o Upper Airway (referred)

15. Murmurs How do you describe a murmur ? Intensity (Grade 1-6) Location (PMI – point of maximal intensity; right/left/ sternal , apical/basilar) Timing (Systolic v. Diastolic v. Continuous) Pitch/Frequency (high/med/low, musical/harsh) Shape (plateau v. decrescendo v. crescendo-decrescendo)

16. Murmurs Grading System : Freeman and Levine I/VI – Very focal; faint II/VI – Faint, but more easily heard than a grade I III/VI – Moderately loud and easily heard (over larger area on same side) IV/VI – Loud murmur heard over large area including the opposite side (discern between 2 murmurs) V/VI – Palpable thrill over PMI VI/VI – Audible with stethoscope off of body wall

17. Murmurs http://www.littmann.com/wps/portal/3M/en_US/3M-Littmann/stethoscope/littmann-learning-institute/heart-lung-sounds/?mmmSsoError=1010|Invalid%20Username%20and%20Password%20combination. Early Systolic Pansystolic

18. Murmurs Some Causes… Valve insufficiency/regurgitation (Chronic Valve Disease) Valve stenosis Septal defects Anemia (physiologic murmur)

19. Lung Sounds Location of sounds is important to note… Normal bronchovesicular sounds Crackles ( rales ) Wheezes ( rhonchi ) r/o stridor & stertor (upper airway)

20. Arrhythmias Causes of arrhythmias: Primary conduction disturbance SA Node, AV Node, fibers (blocks) Secondary to heart disease Enlarged heart (dilated, thicker, etc) Secondary to systemic illness Endocarditis , GDV, splenic disease, hyperthyroid, pheochromocytoma , anemia Secondary to electrolyte imbalances Potassium, Calcium, Sodium Secondary to toxin/drug ingestion

21. Arrhythmias Sinus rhythm (normal) Respiratory sinus arrhythmia (normal) Faster on inspiration – vagal tone is inhibited Tachyarrhythmia SVT, V- Tach /AIVR, A-Fib Bradyarrhythmia AV Blocks, Sick Sinus Syndrome, SA disease, escape rhythms Premature Beats APC v. VPC Gallop Rhythm

22. Arrhythmias Normal ECG

23. Arrhythmias VPC’s, (Ventricular Premature Contractions)

24. Arrythmias V- Tach (Ventricular Tachycardia)

25. Arrhythmias APC’s ( Atrial Premature Contractions)

26. Arrhythmias AV Block (1 st Degree & High Grade 2 nd Degree)

27. Arrhythmias A-Fib ( Atrial Fibrillation)

28. Gallop Rhythm Gallop (S3 sound)

29. Types of Cardiac Disease Congential Defects (ASD/VSD, PDA, Tetrology of Fallot ) Endocardiosis /Chronic Valve Disease (insufficiency) Valvular Stenosis (congenital v. acquired) Dilated Cardiomyopathy (dogs) Hypertrophic Cardiomyopathy (cats) Pulmonary Hypertension Systemic Hypertension (primary v. secondary)

30. Pathophysiology of Disease Abnormal blood flow (can be d/t arrhythmia, cardiomyopathy , etc)  decreased perfusion Stimulates RAAS ( Renin-Angiotensin-Aldosterone System) Hormones increase preload, vascular tone, and affect heart myocytes Structural changes ensue: Eccentric hypertrophy Concentric hypertrophy Chamber dilation

31. Pathophysiology of Disease

32. Congestive Heart Failure (CHF) Left sided Dyspnea Pulmonary Edema Nasal fluid/discharge Right sided Dyspnea Ascites Jugular Pulses

33. CHF Chest rads (needed for diagnosis)

34. CHF

35. CHF Treatment : Oxygen Therapy Lasix ( furosemide ) 2mg/kg IM or IV (dog) 1mg/kg IM or IV (cat) Nitroprusside CRI Sedation ( Torb – beware Ace and Dexdomitor )

36. Atrial Thromboembolism aka “Saddle Thrombus” - Cats!! Gallop rhythm, often underlying heart disease like HCM/RCM/HOCM Due to hypercoagulable blood in chambers (pooling) Hind end paralysis (bilateral > unilateral), usually deep pain negative Cold limbs, cyanotic pads Painful!!

37. ATE Negative Prognostic Indicators : Decreased Temperature, HR Bilateral (versus unilateral) In CHF Treatment : Pain management ( hydromorphone , fentanyl ) Oxygen therapy Lasix (if in CHF – 1mg/kg) +/- Thrombolytic therapy (aspirin, clopidogrel , heparin)

38. What does it all mean?? Do we have lung disease or is it something else? Primary v. secondary diseases (asthma/pneumonia v. non- cardiogenic pulm edema/pleural effusion/pericardial effusion v. CHF) Is cardiac disease the underlying cause? What diagnostics and treatments are indicated?

39. “We’ve got a code 1 trouble breathing…”

40. References Braunwald , E. Heart Disease: A Textbook of Cardiovascular Medicine – 5 th Ed. Philadelphia: W.B. Saunders Co., 1997 Fox, Sisson, Moise . Textbook of Canine and Feline Cardiology: Principles and Clinical Practice – 2 nd Ed. Philadelphia: W.B. Saunders Co., 1999. Drobatz , J.K. Emergency Management of Respiratory Distress. In: Proceedings of the District of Columbia Academy of Veterinary Medicine; 2004.

41. Questions?