For dogs with congestive heart failure (CHF) due to myxomatous mitral valve disease (MMVD), the standard chronic oral regimen is pimobendan 0.5 mg/kg/day divided q12h, furosemide at the lowest effective dose titrated to clinical response, and benazepril 0.25–1.0 mg/kg PO q24h (or q12h at higher doses). FDA DailyMed An…+2

Pimobendan is dosed at 0.5 mg/kg/day PO divided into two portions administered approximately 12 hours apart. The two portions are not required to be equal.FDA DailyMed An… In dogs with advanced or refractory CHF, off-label dose escalation beyond 0.5–0.6 mg/kg/day is practiced clinically, with a reported median dose of 0.76 mg/kg/day (range 0.39–1.31 mg/kg/day) in that population.Journal of Vete… Pimobendan should be continued on the day of anesthesia as scheduled.AAHA Clinical G…

Furosemide is the first-line loop diuretic and is titrated to the lowest dose that controls clinical signs. In dogs with advanced CHF, the threshold for adding adjunctive medications is a total daily furosemide dose exceeding 4 mg/kg/day despite concurrent pimobendan and a maximally tolerated angiotensin-converting enzyme inhibitor (ACEI) dose.Journal of Vete… For acute decompensation, furosemide has been administered as an IV bolus of 4 mg/kg followed by repeated doses of 3 mg/kg IV q12h.Journal of the… Furosemide should also be continued on the day of anesthesia.AAHA Clinical G…

Benazepril is dosed at 0.25–1.0 mg/kg PO q24h; the low end of this range (0.26–0.58 mg/kg q24h) may be less effective than higher or twice-daily dosing. Evidence suggests the RAAS-mitigating effects of benazepril are dose-dependent, and higher doses may be associated with improved clinical outcomes.Journal of Vete…+1 In dogs with advanced CHF, the ACEI dose may need to be reduced or discontinued if worsening azotemia develops — this occurred in 6 dogs in one advanced heart failure cohort, with discontinuation in 2.Journal of Vete…

The clinical benefit of adding an ACEI to dual therapy (pimobendan + furosemide) is not established by prospective survival data. The VALVE trial showed no statistically significant difference in median time to cardiac death between dual therapy (227 days) and triple therapy with ramipril (median time was more than a month shorter in the triple therapy group, though not significantly so).Journal of Vete… The QUEST trial established that furosemide + pimobendan (median 267 days to endpoint) is superior to furosemide + benazepril (median 140 days to endpoint).Journal of Vete…+1 Despite this, triple therapy (furosemide + pimobendan + ACEI) remains a current ACVIM consensus recommendation for chronic CHF management.Journal of Vete…

Quadruple therapy adds spironolactone 2 mg/kg PO q24h to the furosemide + pimobendan + ACEI backbone. Spironolactone at 2 mg/kg PO q24h is the label dose; increasing to 4 mg/kg PO q24h does not produce dose-dependent differences in RAAS biomarker suppression.Journal of Vete… Spironolactone has demonstrated survival benefit when added to furosemide and benazepril in dogs with CHF secondary to MMVD in specific clinical populations.Journal of Vete…

Would you like guidance on when to transition from triple to quadruple therapy, or how to manage the furosemide dose escalation threshold in refractory CHF?