Review outlines anaesthetic risk framework for dogs with MMVD: full analysis

Dogs with myxomatous mitral valve disease routinely present for anaesthesia outside cardiology settings, and a new narrative review in the Journal of Small Animal Practice aims to give clinicians a more structured way to assess and manage that risk. The paper, by Levinzon, Köster, and Vettorato, focuses on pre-anaesthetic risk assessment and management across a “spectrum of care,” reflecting the reality that these cases are handled in settings ranging from first-opinion practice to specialty referral. (academic.oup.com)

That matters because MMVD is both common and variable. ACVIM’s consensus statement says roughly 10% of dogs seen in primary care have heart disease, and MMVD accounts for about 75% of canine heart disease cases seen by veterinary practices in North America. The same guidance notes that stage matters: some dogs have structural disease without clinical signs, while others have current or prior congestive heart failure, pulmonary hypertension, arrhythmias, or other complications that can materially change anaesthetic planning. (academic.oup.com)

The review enters a space where clinicians have had guidance, but not always a unified framework. Existing expert recommendations stress that early-stage B1 dogs generally tolerate anaesthesia well, but management becomes more nuanced as disease advances. In clinically affected dogs, the goal is usually to preserve forward flow while limiting regurgitation, which means avoiding bradycardia, avoiding increases in systemic vascular resistance, and using conservative fluid rates rather than reflexively giving large boluses for hypotension. Elective procedures in dogs with severe heart failure should be delayed until the patient is medically stabilized when possible. (cliniciansbrief.com)

The likely contribution of the new review is synthesis. Based on the abstract and surrounding literature, the authors appear to combine traditional risk tools, disease staging, and practical anaesthetic principles into a single decision-making model. That’s timely, because the field has also been moving toward better objective risk markers in MMVD. Recent research has linked progression risk to factors including heart enlargement, NT-proBNP, and resting heart rate, while a 2024 retrospective study found shock index and heart rate were strong indicators of congestive heart failure in dogs with MMVD. Those tools are not anaesthetic scores by themselves, but they reinforce the idea that risk assessment in these dogs should go beyond a generic physical status label. (academic.oup.com)

Industry and clinical commentary around MMVD anaesthesia has been broadly consistent with that message. A Clinician’s Brief review on anaesthesia for dogs with MMVD recommends opioid- and benzodiazepine-based protocols for many patients, cautions against alpha-2 agonists because of their effects on afterload and heart rate, and notes that there’s still no universal consensus on whether ACE inhibitors should be withheld on the day of anaesthesia. The authors there say their preference is not to stop cardiac medications when disease is well managed, underscoring how much peri-anaesthetic planning still depends on the individual patient’s hemodynamics and medication burden. (cliniciansbrief.com)

Why it matters: For veterinary teams, this review is less about introducing a single new drug protocol and more about supporting better triage. In practice, the biggest value may be helping teams decide which dogs can proceed in general practice with standard monitoring, which need a more tailored protocol and tighter fluid management, and which should be referred or delayed. That’s especially relevant for common procedures like dentistry, where the need for anaesthesia is routine but the cardiac history may be anything but routine. A more explicit spectrum-of-care model could also help practices explain tradeoffs to pet parents in a way that feels concrete rather than vague or overly reassuring. (cliniciansbrief.com)

The review also lands as MMVD care becomes more sophisticated overall. Evidence-based treatment recommendations have evolved in recent years, including support for pimobendan in preclinical dogs with cardiomegaly from the EPIC trial, while other areas, such as ACE inhibitor use in some preclinical patients, remain less definitive. Against that backdrop, anaesthetic planning is increasingly tied not just to whether a murmur is present, but to where the dog sits on the disease spectrum and what therapies are already in play. (pubmed.ncbi.nlm.nih.gov)

What to watch: The next question is whether this narrative review gets translated into clinic-level protocols, checklists, or referral thresholds, particularly for stage B2 and C patients who fall into the gray zone between “routine” and “high risk.” (academic.oup.com)