SAM I Lecture 9 Part 1

Pulmonary edema - 2-4mg/kg IV q 1h, 3x, or until improved; refractory emergency pulmonary edema - furosemide as CRI

Mild CHF: no repetitive activities, avoid exercise to exhaustion, walking ahead on leash story for dogs

Animals with past or current signs of CHF

Renal failure - rare complication if prior renal disease; cough - human side effect; uncommon in dogs/cats

Avoid diets restricted in protein: can contribute to cardiac cachexia + worsen outcome; avoid high Na people food week 1

Euthanasia due to poor quality of life, recurrent CHF, anorexia/weakness, kidney failure, poor prognosis received

Less info; tolerate well; some respond favorable; same dosage as dogs; cats w/ CHF may live longer

Aldosterone causes sodium + water retention; aldosterone also alters BP via vascular effects + extracellular volume

Improve survival; reduce CHF clinical signs; slow cardiac remodeling; may delay onset of CHF

Loop diuretic - ascending limb of loop of Henle; blocks resorption of chloride + electrolytes; water follows electrolyte

Rate + rhythm control: Diltiazem - sustained release form. preferred; Amiodarone, Digoxin; 140-150/120-130bpm target

Median survival 188d; median time to primary endpoint: 267d

Antidiuretic hormone (vasopressin); endothelin; cytokines - TNF, IL-1; reduced parasympathetic tone

Caution for concurrent use w/ nitrates (hypotension); In Chronic CHF: mod-severe pulm. hypertension (>50-80mmHg) w/ sign

Reduced risk of worsening CHF; adverse events not more common in Spiro/Benazepril group

Progression; owner non-compliance; medication admin failure; dietary non-compliance; new onset arrhythmias

Hyperkalemia more likely at higher dose; more if creatinine >mildly elevated; azotemia w/ concurrent hydrochlorothiazide

Hypotension - delay use if dehydrated or borderline BP; GI side effects - vomiting, diarrhea, anorexia

Improves clinical signs; improves survival or time until worsening CHF

SE: dehydration, azotemia, hypokalemia, hypochloremia, hyponatremia, metabolic alkalosis

Animals w/ structural disease w/ no clinical signs; 1: no or mild cardiac enlargement; 2: cardiac enlargement

Animals w/ end-stage CHF that is refractory to standard Rx

Sodium nitroprusside, dobutamine, dopamine; nitroglycerin; ARB/neprilysin inhibitors; SGLT2 inhibitors

Produces grater diuresis + natriuresis; fewer side effects + electrolyte changes; 0.1-1mg/kg/hr CRI in 5% dextrose water

Reduced renal perfusion >>> RAAS; angiotensin II causes: vasoconstriction, release of aldosterone, ^ thirst

Loop diuretic; has minor potassium sparing effects; often effective at very low dose; used when diuretic resistance seen

Useful for dogs w/ pulmonary hypertension; improves clinical signs +/- reduces PA pressure; Tadalafil also reported

Sinus tachycardia; slow CRT, weak arterial pulses, hepatomegaly, ECG voltage changes, arrhythmias

Described at higher doses than recommended; TID dosing, or up to 0.6mg/kg BID, sometimes higher

Aldosterone breakthrough: persistent aldosterone elevation despite RX w/ ACEi or angiotensin receptor blockers

Improved survival in people w/ CHF; low dose in dogs - 1mg/kg/d, most studied dose in dogs 2mg/kg/d (possible q 12h)

Approved in dogs w/ CHF due to MMVD, CHF due to DCM; SE: uncommon - d+, tachycardia/arrhythmia, ^ excitability

Animals at risk of heart disease; no structural heart disease yet

Remove if causing difficulty breathing; remove as much pleural effusion as possible

Pimo tx dogs lived longer until CHF; Endpoint 1228d; no ^ in adverse events; 1059d survival time

Aldosterone also stimulates LV remodeling via fibrosis + hypertrophy

Amiodarone, Sotalol, Mexiletine

At recheck, if no drug changes, start slow transition to new diet; give options for new diet; HeartSmart website

Reduces proteinuria; +/- improved survival (dogs, cats)

Atrial fibrillation; supraventricular tachycardia; ventricular tachycardia

Take away furosemide + replace or add to furosemide; some pick this before furosemide; limited experience in cats

Remove somewhat sparingly to reduce clinical signs; try to mobilize fluids w/ additional cardiac drugs

Reduces blood pressure; reduced hypertensive events

Sildenafil: Pulmonary hypertension, R-CHF, refractory L-CHF; pay attention to BUN or creatinine - azotemia tolerance

Impairs Na/K/Cl cotransporter mechanism; "high ceiling" - wide dose range; rapid onset - often see effect in 30min

NT-proBNP, rads, PE consistent w/ CHF; Echo: atrial enlargement, B-lines, pleural/pericardial effusion, ascites

Echo compatible w/ bad heart dz; dilated hepatic veins on abd. U/S; cardiac gallop; pulmonary crackles

SE: Vomiting, pancreatitis, blood dyscrasia, deafness w/ rapid IV injections

Severe CHF requiring hospitalization: cage rest only

Mild CHF - 2mg/kg q 12-24hr; advanced - up to 4mg/kg q 8h; lower dose in cats; resistance may develop over time

Angiotensin II causes: stimulate ADH release, sympathetic stimulation, myocardial fibrosis + promotes cardiac remodeling

Altered myocardial energy metabolism; nitric oxide; prostaglandins; antioxidant depletion

Repeated __ leads to protein loss and cachexia

Use in dogs + cats w/ CHF (enalapril, benazepril, lisinopril, ramipril); role in horses + other species less clear

Azotemia - usually due to excessive concurrent diuretic, azotemia usually resolves w/ diuretic dose reduction

Sudden death - arrhythmic; thromboembolic disease; refractory CHF or acute recurrence; euthanasia

For pulmonary hypertension due to CHF or other causes; Phosphodiesterase V inhibitor - NO donor; 1-3 mg/kg BID-TID

Optimized ACEi/Spironolactone; Furosemide @ higher dose, Torsemide (10x potency of furosemide); More Pimobendan

Use to prevent/delay onset of CHF (maybe in DCM or animals w/ marked LAE)

MOA; Improved blood test; anecdotal reports; preference; opinion; consensus; evidence based vet med

Remove if: causing difficulty ambulating, affecting appetite, pressing on diaphragm + contributing to dyspnea

Use w/ lowest possible dose of furosemide; measure + follow renal function; delay use in animals w/ hypotension

Mild/moderate sodium restriction is indicated in CHF: severe sodium restriction might be assoc. w/ worse outcome

For stage C tx w/: furosemide as needed for congestion, Pimo, angiotensin converting enzyme inhibitor, spironolactone

Positive inotrope w/ vasodilator properties (pulmonary + systemic); "inodilator"; oral absorption in 1 hour

Lower percentage of dogs in Spiro/Benazepril group reached endpoint at 360d; reduced risk of dying of cardiac cause

Indicated for cardiogenic edema; pulmonary edema, pleural effusion, ascites; most commonly used diuretic in vet med

SNS, Renin-angiotensin-aldosterone, renal sodium + water retention; atrial natriuretic peptides; baroreceptors

Clinical signs compatible w/ CHF; radiographic evidence of CHF (2 views); elevated NT-proBNP; jugular distension/ascites

Pimobendan; ACE Inhibitor; Spironolactone; Diuretics (Furosemide or Torsemide)

Calcium sensitizer (inotropic action); Phosphodiesterase III inhibitor (vasodilator + inotropic action)

Delay onset of CHF (maybe, in dogs w/ DCM); probably minimal effect in dogs w/ MMVD

Very low profile; GI upset; electrolyte depletion w/ concurrent hydrochlorothiazide use

Weak diuretic; mineralocorticoid receptor antagonist; aldosterone receptor antagonist; others compounds stimulate these

Furosemide/torsemide; pimobendan; ACE-I; spironolactone; anti-arrhythmic drugs; sildenafil; beta-blockers; digoxin