Alan Livingstone said he made the horrific discovery after calling at the Bellshill property with a legal document.
He rescued the Staffordshire bull terrier and alerted the police and the Scottish SPCA.
Mr Livingstone said: “The house had been trashed but for me the main thing was the treatment of the dog which was nothing short of barbaric. The poor thing was standing in its own filth in the shower tray.
“A locksmith with me was physically sick at the sight.”
Mr Livingstone said he had taken legal action to evict the tenant from the terraced house in West End Drive over thousands of pounds in rent arrears.
When he went there last Wednesday a neighbour said the tenant had been gone for a week or 10 days.
He said: “Opening the letterbox, I heard a dog whining. I thought ‘Surely they’ve taken the dog with them?’, but we got into the house and there it was in the bathroom.
“It gave me a look that said ‘Get me out of here’.”
A filthy cage was among a huge number of items dumped in the front garden of the house.
Mr Livingstone said the dog’s condition gave him cause for concern initially, but although it clearly had not been fed it appeared happy enough after being released.
He added: “I want to highlight this to make people aware that this sort of thing goes on.
“I only hope the person responsible is never allowed to keep an animal again.
“If you can’t look after a pet why not give it to an organisation who can?”
The Scottish SPCA was unable to provide details of the dog’s condition.
Chief Inspector John Chisholm said: “We were called out to a property in Bellshill and removed a dog as part of an ongoing investigation.
“Anyone concerned about any animal’s welfare should call us on 03000 999 999.”