pimobendan dosing for a Cavalier King Charles with MMVD

Of course. The key with pimobendan in Cavaliers with MMVD isn't just the dose, but the timing. Let's make sure we're starting it at the right stage.

According to the ACVIM consensus guidelines and the results of the EPIC trial, pimobendan is indicated for dogs in Stage B2 or Stage C of myxomatous mitral valve disease.

* Stage B1: A murmur is present, but there is no radiographic or echocardiographic evidence of significant cardiac remodeling. Pimobendan is not indicated at this stage.
Stage B2: A murmur is present with* objective evidence of cardiac remodeling (cardiomegaly). This is defined by meeting specific radiographic AND/OR echocardiographic criteria, such as:
* Echocardiographic: Left atrial-to-aortic ratio (LA:Ao) ≥1.6 and normalized LV internal diameter in diastole (LVIDdN) ≥1.7.
* Radiographic: Vertebral Heart Score (VHS) >10.5 (though Cavaliers can have a slightly higher baseline).

If your patient meets the criteria for Stage B2 or is in active heart failure (Stage C), the correct dose is:

Pimobendan: 0.25–0.3 mg/kg PO Every 12 hours

A crucial administration point is to give it on an empty stomach (at least one hour before a meal), as food can decrease its bioavailability by about 30%.

In summary, confirm the patient is in Stage B2 with appropriate imaging before initiating therapy. If they are, that's the dose to use. Let me know if you have radiographs or echo findings you'd like to discuss.