Preliminary evaluation of the efficacy of intravenous magnesium sulfate for the treatment of ventricular arrhythmias in 16 dogs

Key nutrients important in the management of canine myxomatous mitral valve disease and heart failure

The most common cause of heart failure in dogs is myxomatous mitral valve disease (MMVD), which accounts for approximately 75% of canine heart disease cases and is especially common in smaller dogs. Although low-sodium diets have been recommended for humans with heart diseases for decades, there is little evidence to support this practice in dogs. In recent years, however, it has become clear that other nutrients are important to heart health. Dogs with heart disease secondary to MMVD experience patterns of metabolic changes that include decreased mitochondrial energy metabolism and ATP availability, with increased oxidative stress and inflammation. These changes occur early in disease and progress with worsening heart disease. Key nutrients that may support normal function and address these changes include omega-3 fatty acids, medium-chain triglycerides, magnesium, antioxidants including vitamin E and taurine, and the amino acids methionine and lysine. The long-chain omega-3 fatty acids provide anti-inflammatory, antithrombotic, and other benefits. Medium-chain fatty acids and ketones derived from medium-chain triglycerides provide an alternative energy source for cardiac mitochondria and help reduce free radical production. Magnesium supports mitochondrial function, normal cardiac rhythm, and provides other benefits. Both vitamin E and taurine counter oxidative stress, and taurine also has direct cardiac benefits. Dogs with MMVD have reduced plasma methionine. Methionine and lysine are important for carnitine production as well as other functions. This article reviews the evidence supporting the functions and benefits of these and other nutrients in MMVD and other cardiac conditions.

Diagnosis and management of arrhythmias in dogs: A cross-sectional online survey among Flemish veterinary practitioners

Background

Diagnosis as well as management of arrhythmias in dogs can be challenging for veterinary practitioners. The aim was to describe ECG availability and use, as well as the diagnostic and therapeutic experiences and preferences of Flemish veterinarians regarding cardiac arrhythmias in dogs.

Methods

Cross-sectional online survey among veterinarians in Flanders (Belgium).

Results

An ECG device was available for 55 out of 102 respondents (54%) and 41 (43%) claimed to use it in case of arrhythmia suspicion. Insufficient knowledge about ECG interpretation and immediate patient referral upon detection of an abnormal heart rhythm were the most important reasons for not having, or not using, an ECG. About half of the respondents (56%) had never used anti-arrhythmic drugs in dogs, although only a few reported having had a negative experience. Frequently provided reasons for not using anti-arrhythmic drugs included insufficient knowledge and a low number of dogs with arrhythmias.

Conclusion

Most veterinarians reported having little or no expertise with arrhythmias in dogs. Electrocardiogram availability and use among respondents was moderate and too often restricted by insufficient ECG interpretation skills. Continued efforts are needed to increase the confidence and knowledge of veterinarians about arrhythmias in dogs.

Fluid Therapy During Cardiopulmonary Resuscitation

Cardiopulmonary arrest (CPA), the acute cessation of blood flow and ventilation, is fatal if left untreated. Cardiopulmonary resuscitation (CPR) is targeted at restoring oxygen delivery to tissues to mitigate ischemic injury and to provide energy substrate to the tissues in order to achieve return of spontaneous circulation (ROSC). In addition to basic life support (BLS), targeted at replacing the mechanical aspects of circulation and ventilation, adjunctive advanced life support (ALS) interventions, such as intravenous fluid therapy, can improve the likelihood of ROSC depending on the specific characteristics of the patient. In hypovolemic patients with CPA, intravenous fluid boluses to improve preload and cardiac output are likely beneficial, and the use of hypertonic saline may confer additional neuroprotective effects. However, in euvolemic patients, isotonic or hypertonic crystalloid boluses may be detrimental due to decreased tissue blood flow caused by compromised tissue perfusion pressures. Synthetic colloids have not been shown to be beneficial in patients in CPA, and given their documented potential for harm, they are not recommended. Patients with documented electrolyte abnormalities such as hypokalemia or hyperkalemia benefit from therapy targeted at those disturbances, and patients with CPA induced by lipid soluble toxins may benefit from intravenous lipid emulsion therapy. Patients with prolonged CPA that have developed significant acidemia may benefit from intravenous buffer therapy, but patients with acute CPA may be harmed by buffers. In general, ALS fluid therapies should be used only if specific indications are present in the individual patient.