Part one of this article addressed the importance of sedatives, identifying the source of respiratory distress, clinical signs of CHF, etc.
ER management of CHF
Protocols for managing CHF associated with MMVD, the most commonly seen form of CHF in dogs, are very well established, as is heart disease staging. For hypertrophic cardiomyopathy (HCM) in cats and dilated cardiomyopathy (DCM) in dogs, there is less well-synthesized information, but the same principles generally apply. Because the available consensus statement pertains specifically to MMVD, the following recommendations are based on the evidence used in the consensus statements, with some supporting information for DCM and HCM. Additional therapies in cats are often informed by advanced imaging and more definitive diagnoses, such as echocardiography.9,13
Stage C MMVD, per the ACVIM 2019 consensus statement, is addressed specifically to dogs that have developed CHF and respond to treatment. Even if these patients achieve improvement/resolution of failure, they remain in this stage classification. If they become refractory to standard therapy recommendations, they are classified as stage D. Ultimately, our goal in CHF is to ensure adequate oxygen delivery to tissues and maintain hemodynamic stability. Medication and therapy focus on various aspects of heart function, including:7
- Decreasing oxygen demand
- Improving contractility
- Managing heart rate
- Heightening afterload
- Optimizing preload
- Improving overall cardiac output
- Decreasing regurgitation of affected valves
- Addressing any pulmonary dysfunction
