Case 14 — Bradycardia

Primary clinician: Brad Gavaghan, DVM, DACVIM (Cardiology) and Darcy Adin, DVM, DACVIM (Cardiology)
Supervising clinician: Mark D. Kittleson, DVM, PhD, DACVIM (Cardiology)

Signalment

  • Species: Canine
  • Breed: American cocker spaniel
  • Age: 10 years
  • Sex: Male castrated
  • Weight: 12 kg
  • Name: Houdi

Initial Visit

Presenting Complaints

  • Heart rate slow & erratic / Weight loss

Pertinent History

  • Houdi was diagnosed with bradycardia and a I/VI systolic murmur last month during an evaluation for weight loss.
  • The referring DVM would like to plan a gastroduodenoscopy and referred Houdi for cardiac evaluation.
  • The owner reports normal activity and good appetite.
  • He has also begun to put on more weight since this problem started a few months ago.
  • Houdi was diagnosed with pancreatitis 2 years ago.

Physical Examination

  • BAR; T = 102.2°F; P = 60; RR = panting
  • IV/VI left apical murmur (II/VI on the right). Strong femoral pulses; pink MM with 1-sec CRT.
  • Clear lung sounds bilaterally.
  • Abdominal palpation unremarkable.
  • Slight enlargement of the prescapular lymph nodes.

Comments

  • ECG: Non-atropine-responsive sinus bradycardia (HR = 55 bpm), with failure of appropriate response from alternate pacemakers.
  • ECHO: Moderate mitral regurgitation with valve thickening and LA enlargement. IVSd 0.8 cm (normal); LVIDd 4.0 cm (increased); LVIDs 2.7 cm (increased); SF 39%; LVFWd 0.8 cm (normal); Ao:LA 15:26 (increased).

Discharge Summary

Houdi was diagnosed with moderate mitral regurgitation and sinus bradycardia that was not atropine-responsive. A temporary pacemaker was recommended if he is placed under general anesthesia. A permanent pacemaker may be required in the future.

Three Months Later

Presenting Complaints

  • Rear legs give out

Pertinent History

  • History of pancreatitis.
  • Shaky rear legs and not jumping up as often. Every 3–4 days his rear legs will give out. The owner describes it as stumbling.
  • Currently has protein-losing nephropathy.
  • Being seen here for either a temporary or permanent pacemaker in order to undergo anesthesia for a kidney biopsy.
  • Behavior unchanged. Eating and drinking well.
  • Watery diarrhea for the past two days.
  • No coughing, wheezing, or vomiting.
  • Taking metronidazole 250 mg ½ tab TID for the past 2 months.
  • Was on carprofen 20 mg BID but taken off 2 days ago.
  • Was on enalapril 5 mg SID but taken off because of kidney problems.

Physical Examination

  • BAR; Weight 12.0 kg; T = 101.4°F; P = 44 bpm; RR = panting. MM pink; CRT 1 sec.
  • Integument: Papillomas on head; small lipoma-like mass on right side. Shiny coat, clear skin, well hydrated.
  • EENT: Small amount of mucous from both eyes with some opacity. Small amount of ear wax. Nose clear. Severe tartar on teeth.
  • MS: Symmetrical, well muscled, no lameness. BCS 5/9.
  • CV: Very irregular slow heart rate. Grade III/VI left-sided systolic murmur. Strong pulse quality. Approximately 2-sec pauses intermittently between beats.
  • Respiratory: Clear lung sounds, no crackles.
  • GI: No masses or organomegaly.
  • GU: No secretions detected. Neuro: Not evaluated. LN: Not enlarged.

Problems

  • Protein-losing nephropathy
  • Bradycardia / Stumbling episodes

Echocardiogram

  • Mild mitral regurgitation with mild valve thickening and mild left atrial enlargement.
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