|Reason for Visit||Has been coughing daily for the past 2 to 3 weeks; cough seems dry but might occasionally be productive (retch at end of cough with swallowing).|
|Medications||Jazzy is currently receiving Heartgard® Plus and Frontline®. He is not on any other chronic medications.|
Please review Jazzy's clinical history.
|Attitude/Demeanor||Seemed normal until 24 hours ago.|
|Coughing||Has been coughing daily for the past 2 to 3 weeks. Cough seems dry but might occasionally be productive (retch at end of cough with swallowing).|
|Abnormal Respirations||Tachypnea and respiratory distress. Owner reports rapid breathing recently and "trouble breathing" over the past 24 hours which prompted the veterinary examination.|
|Exercise Tolerance||Has been slowing down, but was still taking short walks.|
|Sleep Patterns||Has seemed restless at night over the past week with some coughing.|
|Weight Change (loss or gain)||None observed/known.|
|Usual Diet||Purina One® with some table scraps and cold cut treats.|
|Vomiting||None - occasional retch after cough but nothing produced.|
|Change in urinary habits||No.|
|Change in drinking habits||Been drinking more past few days.|
|Other symptoms or signs||Occasionally scratches ears.|
Please review the results of Jazzy's physical exam.
|Body Condition||Good, BCS 4/9.|
|Attitude||Alert, somewhat anxious.|
|Mobility | Gait||Normal gait upon inspection.|
|Posture||Standing or sitting.|
|Hydration||Suspect mild dehydration.|
|Body Temperature||100.3 F|
|Arterial Pulse - rate, regularity, intensity||142 beats/min, regular, normal strength.|
|Respiratory Rate & Effort||40, mild inspiratory effort.|
|Mucous Membranes - Color & CRT||Pale to pink / 3 seconds.|
|Jugular Venous Pulse & Pressure||Normal.|
|Abdominal Palpatation||Liver is palpably enlarged; moderate-size bladder.|
|Oral Cavity||Mild dental calculus, no periodontal disease.|
|Other Abnormalities||Slight odor from ears.|
Direct HR: 142 bpm
Heart Rhythm: Rhythm is regular. Possible infrequent premature beats.
Intensity of Sounds: Abnormal. The first sound is prominent.
Extra Sounds - Clicks or Gallops: No
Precordial Palpation: Precordial thrill (vibration) is evident.
The CEG considers the following differential diagnosis as most likely (and why):
The loud left apical systolic murmur is compatible with mitral regurgitation. In an older small breed dog, mitral regurgitation is likely due to myxomatous mitral valve disease, a degenerative disorder (also called valvular endocardiosis). The findings of cough and inspiratory crackles may indicate cardiogenic pulmonary edema and therefore left-sided congestive heart failure is a top differential diagnosis. Crackles may also be noted in conditions such as pneumonia, small airway disease, or pulmonary fibrosis and therefore a primary respiratory disease should be on the differential list for Jazzy's symptoms. In such cases, the mitral regurgitation may simply be a comorbid condition and not the cause of the respiratory distress. Dilated cardiomyopathy is certainly possible but is an uncommon to rare cause of congestive heart failure in small breed dogs.
The CEG considers the following diagnostic tests as the highest priority:
Jazzy fits the clinical picture of age-related mitral valve degeneration with development of heart failure. Blood pressure measurement is important in patients with mitral regurgitation because a high afterload may cause a greater volume of blood to regurgitate across the mitral valve. It is important to remember that heart disease does not cause high blood pressure, but high blood pressure can exacerbate heart disease. Common risk factors for hypertension include chronic kidney disease and Cushing's disease. If Jazzy's BP was elevated, therapy to control his BP would be important.
Chest radiography (once the dog is stable) is mandatory to confirm the diagnosis and evaluate the severity of pulmonary edema. Echocardiography is advised to confirm the abnormalities present and evaluate cardiac size and function.
Abdominal imaging (radiography or ultrasound) are not indicated at this time in our opinion based on a lack of abdominal signs or concerns about neoplasia; the hepatomegaly could simply relate to congestive heart failure. Alternatively, abdominal ultrasound might be useful if biochemical tests indicate hepatocellular injury or disease. This is mainly an issue of cost/resources at this point in terms of priority (as one can reasonably argue that hepatomegaly is an indication for abdominal imaging).
Baseline bloodwork is advised in this geriatric patient to evaluate overall organ function and in particular kidney function and electrolyte status prior to diuretic therapy. Thus, a serum biochemical profile is high priority; a CBC and urinalysis would provide more complete "baseline" data, but are of lower priority. There are no overt signs of hypothyroidism and unless a thyroxine is part of the profile it would be considered low priority.
A heartworm antigen test (with or without microfilaria test) can be done because respiratory signs could related to heartworm disease; however, the dog is taking preventative so this test is lower priority unless the dog resides in an "endemic" or macrolide-resistant region.
Electrocardiography can be performed to document the suspected premature beats. If premature beats are infrequent, however, a short recorded ECG strip may be normal. However, at this time, a Holter ECG would be considered premature. Diagnostic centesis is not indicated in this patient; there is no evidence of ascites or of pleural effusion.
An NT-proBNP or BNP may also be considered to support a cardiogenic cause for the respiratory distress (in particular, a low value would argue against CHF) and potentially to provide a baseline for therapeutic monitoring (though more data are needed before this can be routinely recommended). Natriuretic peptides are typically very high in dogs with CHF, but also can be elevated in advanced, compensated valvular disease without overt pulmonary edema. Thus diagnosis and any therapy should be based on a comprehensive evaluation of all findings, not a laboratory test. If clinical improvement with initial therapy is not observed or additional complications develop, referral to a cardiologist should be considered.
Please review Jazzy's thoracic radiographs
Technical Quality: Acceptable. Slight rotation on the lateral projection and VD.
Pulmonary Venous Congestion: There is prominent pulmonary vasculature. Pulmonary vessels are prominent but not definitely large. There is possible enlargement of the right caudal pulmonary vein on VD and cranial vein on left lateral.
Pulmonary Infiltrate Distribute: Distribution is heavy unstructured interstitial to alveolar.
Other Findings: Hepatomegaly; some aerophagia (with food in stomach).
Please review Jazzy's lab results
|BUN||38 mg/dL Normal: <30 mg/dL|
|Creatinine||1.8 mg/dL Normal: 0.3 - 2.1 mg/dL|
|Sodium||149 mEq/dL Normal:138 - 154 mEq/dL|
|Potassium||3.7 mEq/dL Normal: 3.6 - 5.2 mEq/dL|
|Chloride||112 mEq/dL Normal: 105 - 119 mEq/dL|
|ALT||32 IU/dL Normal: <75 IU/dL|
|ALP||56 IU/dl Normal: <100 U/dL|
|Glucose||104 mg/dL Normal: 68 - 126 mg/dL|
|Heartworm Test Results||Negative|
|Urinalysis - USG||All values within normal limits|
|Urinalysis - Protein||All values within normal limits|
|Urinalysis - Biochemical||All values within normal limits|
|Urinalysis - Sediment Evaluation||All values within normal limits|
|White Blood Cells||All values within normal limits|
|Red Blood Cells||All values within normal limits|
|Platelets||All values within normal limits|
Please review the results of Jazzy's echo
|Subjective - lesions of valves, myocardium, pericardial space||No pericardial effusion; subjectively hyperdynamic left ventricle, thickened mitral leaflets with mitral valve prolapse.|
|LV chamber size and thickness||LV dilated. Normal thickness.|
|Left atrial size||Moderate dilation|
|LVIDd & LVIDs||Diastole (3.4 cm); systole (2.1 cm)|
|LV shortening fraction||38% (within normal range)|
|RA, RV and Pulmonary Artery||Not remarkable (detailed images not shown)|
|Doppler results||Mitral and tricuspid regurgitation; eccentric jet of MR is typical of primary valve disease; velocity of MR predicts normal systemic pressures; increased velocity of TR (~3.6 m/s) predicts moderate pulmonary artery hypertension (~55 mm Hg).|
Please review Jazzy's ECG results.
|Technical quality, leads, paper speed, calibrations||Satisfactory recording; 6 frontal leads and lead 2 rhythm strip recorded; paper speed 50 mm/sec; calibration 5 mm/mV|
|Rhythm - Regular or irregular | Patterns||Regular|
|Heart Rhythm Disturbances||Sinus tachycardia; although auscultated (see Auscultation), no premature complexes were detected during this recording|
|P Wave Abnormalities - morphology, amplitude, duration||Slightly wided (0.55 sec) especially evident in lead III (P-mitrale); normal amplitude (appear smaller due to calibration factor)|
|QRS Abnormalities - axis, morphology, amplitude, duration||Normal frontal axis, upper limit duration, increased voltages (deep Q-waves with 4.8 mV R-waves in lead II suggestive of eccentric LV hypertrophy or dilatation)|
|Abnormal Intervals - PR, QRS, QT||Normal intervals|
|Other||Slurred ST segment|
You're ready to form a diagnosis and treatment plan for Jazzy! Please select your answer to each question below.
THE CEG RECOMMENDS:
The CEG recommends treatment with furosemide, pimobendan, ACEi +/- Spironolactone.
|Initial Therapy||Jazzy was administered 2 mg/kg furosemide IV and allowed to rest in oxygen for 4 hours. Following diuresis he appeared comfortable out of oxygen and was released to his owners on the treatment plan below.
Furosemide - 12.5 mg - one tablet - b.i.d
This is a relatively conservative dosage, and if respiratory signs re-developed, it would be appropriate to increase the dose from the current 1.7 mg/kg to 2.5 mg/kg (i.e. one and one-half 12.5 mg veterinary furosemide tablet).
Enalapril - 2.5 mg - 1.5 tablets - b.i.d
Some cardiologists would use 50% of this dosage initially, especially in dogs with impaired renal function, and would then increase the dose to ~0.5 mg/kg b.i.d. at the first recheck examination. Other ACE inhibitors (benazepril, ramipril, quinipril, etc.) are also approved for treatment of CHF in dogs in a number of countries. There are no clinical trials comparing the relative effects of different ACE inhibitors in dogs with CHF.
Pimobendan - 5.0 mg - 1/2 tablet - b.i.d
This drug can be useful in both initial (hospital treatment) as well as chronic therapy of CHF in dogs.
Spironolactone - 25 mg - 1/4 tablet - b.i.d
Spironolactone has negligible diuretic effects; this drug is used to reduce the negative effects of aldosterone on tissues such as the pro-fibrotic effect of this hormone on cardiac muscle.
|Diet||Avoid high sodium treats and foods such as processed meats, hot dogs, cheese. Typically commercial dry foods contain half the sodium of commercial canned foods.|
|Other Points||Amlodipine was not prescribed because of his normal blood pressure. Occasionally, amlodipine is used to achieve more afterload reduction, but this would be an advanced treatment reserved for Stage D. Atenolol, a beta-blocker, is contraindicated in treatment of active CHF, and the use of beta-blockers in dogs with chronic heart disease is still under study. The CEG does not recommend routine use of this class of drugs in chronic valvular disease.|