The Estate of Carlo DeMarco et al. v. Dr. Martin et al., [2019] ONSC 2788

Full Decision

The use of average wait-times as a defence to causation in a case involving a GP’s failure to refer.

Carlo DeMarco (“the deceased”), died suddenly at the age of 51 years old. Six months prior, his family physician, Dr. Rene Frances Martin (“the defendant”), had conducted a routine physical examination which revealed nothing of concern (“the first visit”). Two months prior to his death, he attended the defendant’s office (“the second visit”) complaining of indigestion, left arm discomfort and feeling faint (“the triad of symptoms”). The defendant prepared a letter of referral to a cardiologist, Dr. Dennis Wong, requesting that the deceased undergo a stress test. The defendant never sent the referral. An autopsy revealed that the deceased suffered from advanced coronary artery disease.

The plaintiffs, relatives of the deceased, alleged that the defendant failed to conduct a proper physical examination in the first visit which occurred six months before the deceased’s death. The plaintiffs further allege that the defendant breached the standard of care by failing to send the stress-test referral to the cardiologist.

The defendant denied that he breached the standard of care in his physical examination at the first visit. He admitted that his failure to send the referral was a breach of the standard of care. Despite the breach, the defendant defended the action on causation.

Ultimately, Justice Mitchell found in favour of the Defendant and dismissed the claim.

Standard of Care: The First Visit

The plaintiffs alleged that the defendant fell below the standard of care in his assessment of the deceased at the first visit (6 months before to death) due to his failure to detect the triad of symptoms displayed at the second visit (two months before his death). The plaintiffs relied on a medical expert in family law medicine who opined that the defendant had failed to conduct an adequate systems review, failed to properly document his assessment, failed to assess the deceased’s cardiac risks, and failed to order a routine ECG. The plaintiffs’ theory relied on the assumption that the deceased had in fact been suffering from the triad of symptoms, or other symptoms of heart disease, at the time of the first visit.

Relying on his own experts, the defendant maintained that the plaintiff was not suffering from any symptoms which would suggest that he had a heart condition at the first visit and that his assessment and charting met the standard.

Justice Mitchell reviewed the standard of care, that of reasonableness, applicable to medical practitioners. Justice Mitchell also commented on the effect of a lack of charting stating:

A lack of charting does not necessarily mean that procedures were not conducted nor is the mere lack of charting prima facie evidence of negligence in conducting the examination. However, a lack of charting makes it more difficult for a court to determine matters of credibility where individuals who are trained to chart did not do so. This failing, despite the opportunity to do so, makes it more difficult for a court to accept that the correct steps were followed and questions asked as it would have been logical for them to be recorded had they been done. [65]

Ultimately, Justice Mitchell determined that the defendant had not breached the standard of care in his assessment of the plaintiff or charting practices. His Honour found that the plaintiff was not experiencing the triad of symptoms at the first visit and additionally, had no apparent cardiac risk factors which would indicate further intervention.


The defendant admitted that he breached the standard of care in failing to send the referral for a stress test to a cardiologist. However, he maintained his breach did not cause or contribute to the plaintiff’s death. The defendant relied on two arguments: (1) even if he had sent the referral, the deceased would not have been diagnosed and treated prior to his death (the “wait-time defence”) and (2) even if the deceased had been diagnosed and treated for coronary heart disease, his life would not have been prolonged because the arrhythmia which led to his death was caused by scarring on his heart muscle and not from his untreated advanced coronary heart disease (the “treatment defence”). Therefore, causation was the primary issue in this case.

Justice Mitchell reviewed the law on causation and determined that the “but for” test was appropriate. He also confirmed that the loss of chance is not compensable in medical malpractice cases:

“Proof that “but for” the defendant’s actions the plaintiff had a better chance of avoiding the outcome does not establish causation. The plaintiff must prove on a balance of probabilities, that the outcome would have been avoided.[74]

The Wait-Time Defence

The defendant argued that based on the cardiologist who was the intended recipient of the referral, Dr. Wong’s, average wait-times for conducting a stress test, the deceased would not have received a diagnosis even if he had sent to referral immediately. Additionally, the defendant claimed that even if the deceased had received a diagnosis, he would not have received treatment prior to his death.

Dr. Wong testified at trial regarding his average wait-time before he would conduct a stress test when referred on a non-urgent basis. Dr. Wong concluded, based on his review of his records, and a computer program created for this purpose, that the average wait-time was between 6-8 weeks at the time of this incident.

The plaintiffs challenged the admissibility of Dr. Wong’s evidence on the basis that it was hearsay. In a separate decision, Justice Mitchell found that Dr. Wong’s evidence was admissible (The Estate of Carlo Demarco et al. v. Dr. Martin et al., 2018 ONSC 5948; previously summarized by Nga Dang.

Dr. Jablonsky, another cardiologist, testified on behalf of the defence. If the results of the stress test indicated further intervention, Dr. Wong would have referred the deceased to Dr. Jablonsky to conduct an angiogram. Dr. Jablonsky testified that the wait-time for an angiogram would have been between 3-4 weeks depending on the urgency. If further intervention was required, such as an angioplasty or bypass surgery, it likely would have been an additional one to two months before treatment.

Justice Mitchell found that, based on the average weight times provided, the deceased would not have received treatment until August 24, 2011, several days after his death.

He concluded that the plaintiffs failed to establish that “but for” the defendant’s breach, the deceased’s coronary artery disease would have been treated prior to his death.

The Treatment Defence

The defendant also argued that even if the deceased had received a diagnosis and treatment of coronary artery disease prior to his death, it would not have prolonged his life because his cause of fatal arrhythmia was due to scarring on his heart muscle and not complications arising from untreated advanced coronary heart disease.

Both parties relied on multiple experts to opine on the cause of death. The primary issue was whether a heart attack caused by coronary artery disease (which the autopsy had revealed the deceased suffered from) or scarring on his heart (likely from a previous ischemic event) ultimately caused his death. The latter could not have been treated and therefore, the failure to send the referral did not cause his death.

The pathology evidence confirmed that the deceased had pre-existing scarring on his heart muscle. While the pathology evidence also confirmed that he suffered from coronary artery disease, it did not reveal mechanisms of a heart attack, such as unstable plaque or a blood clot (two potential causes of a heart attack) as the cause of death.

Ultimately, Justice Mitchell concluded that the plaintiffs had failed to establish causation. While Justice Mitchell found that it was possible that a heart attack alone, or a combination of scarring and a heart attack, could have caused his death, it was not probable. The most likely cause of death was the scarring alone, and therefore the plaintiffs did not establish that “but for” the failure to treat the deceased coronary artery disease, he would not have suffered a fatal arrhythmia at his time of death.


Damages were assessed but not awarded. While damages for loss of care, guidance, and companionship were agreed upon prior to trial, Justice Mitchell also laid out his analysis and assessment for the dependency loss claims of the deceased’s wife and disabled daughter.

Written by

Gabriel joined Gluckstein Lawyers as an articling student in 2017 and is a graduate of the J.D. program from the Faculty of Law at Queen’s University.

As a law student, Gabriel volunteered at the Concordia Student Union Legal Information Clinic where he provided legal information to Concordia undergraduate students. He was also significantly involved at the Queen’s Legal Aid Clinic. As a student caseworker at Queen’s Legal Aid, Gabriel represented clients at the Landlord and Tenant Board, the Social Benefits Tribunal and the Criminal Injuries Compensation Board. Gabriel also volunteered as a group leader where he trained and supervised 10 volunteer student caseworkers.