Mitral valve disease is the defining health problem of the Cavalier King Charles Spaniel. The mitral valve thickens and prolapses, regurgitation begins, the heart enlarges, and eventually congestive heart failure follows. It is progressive, it is inherited, and its prevalence in the breed is high enough that owners should plan for it from the day they collect a puppy.
Prevalence and timeline
Breed club screening data has long shown roughly 50% of Cavaliers with a murmur by five years of age, rising to nearly 100% by ten. The median age at diagnosis in screened populations sits around six to seven years; in unscreened populations it is earlier.
Progression is measured in stages. Stage B1 is a murmur with no cardiac enlargement; B2 adds enlargement; C is overt heart failure. The jump from B1 to B2 typically takes one to three years, and B2 to C a further one to two.
What monitoring costs
An echocardiogram is the standard assessment and costs $400 to $700 at a cardiologist, with auscultation and radiographs cheaper but less informative. Most cardiologists recommend recheck echo every 6 to 12 months once a murmur is detected.
A breeding-scheme cardiac certificate requires examination by a veterinary cardiologist, which is a separate cost for anyone breeding the dog.
| Stage / item | Cost | Frequency |
|---|---|---|
| Cardiology echo | $400–$700 | Every 6–12 months |
| Pimobendan + ACE inhibitor | $90–$250/month | Lifelong from B2 |
| Pulmonary oedema episode | $800–$2,500 | Recurring in stage C |
| Holter monitoring | $350–$600 | If arrhythmia suspected |
| Breeding cardiac certificate | $150–$300 | Per examination |
Lifetime medication
Once in stage B2 or C, treatment is lifelong: pimobendan, an ACE inhibitor, and usually a diuretic. Monthly cost depends on the dog’s weight and the combination, typically $90 to $250. Pimobendan alone, for a 9 kg Cavalier, commonly runs $70 to $110 per month.
Emergency presentations — pulmonary oedema, arrhythmia — cost $800 to $2,500 per episode and become more frequent as the disease advances.
The insurance calculation
MVD is hereditary. Policies that cover hereditary conditions from inception, with no per-condition cap, are the only ones that make sense for this breed. A $3,000 per-condition limit will be exhausted by diagnostics and the first year of medication.
The critical moment is the first murmur. Once a vet records a grade 1 murmur at a routine vaccination appointment, MVD becomes a pre-existing condition and no new policy will cover it. Insure at eight to twelve weeks, before the first auscultation.
- Around half of Cavaliers have a murmur by age five; nearly all by ten.
- Monitoring means echo every 6–12 months, not an annual stethoscope alone.
- Medication is lifelong once cardiac enlargement appears.
- The first recorded murmur closes the door on new cover.
Most Cavalier owners discover MVD at a routine appointment. That single line in the record converts a future $15,000 of care into an uninsurable condition. Bind the policy before the second vaccination, not after.
Key takeaways
- MVD prevalence in the breed makes insurance a planning tool, not an option.
- Per-condition caps are useless for a disease that lasts a decade.
- Diagnostics are a recurring cost, not a one-off.
- Insure before the first auscultation finds a murmur.
