National drug shortage is causing some delay in heart testing in Alberta, doctors say

A nationwide shortage of drugs used for cardiac imaging is leading to delays in testing some cardiology patients in Alberta.

Dipyridamole, a drug administered intravenously during cardiac imaging procedures for people who cannot perform traditional treadmill stress tests, is now in short supply.

The drug widens the blood vessels and replaces the effect of exercise during myocardial perfusion scans, which show how well blood is flowing through the heart muscle.

Health Canada stated a Level 3 deficiency of dipyridamole injections in June, meaning it has “the greatest potential impact on Canada’s drug supply and healthcare system”.

“I don’t have a dose for anyone at this point,” says Dr. Anmol Kapoor, a cardiologist at Advanced Cardiology Consultants and Diagnostics in Calgary.

He ran out of dipyridamole last week and is now deferring the tests, which can show if a patient is developing critical heart block.

“It’s very important. This is a life-saving test and it’s very frustrating that we don’t have access to the medication.”

Kapoor’s team has been trying to find the drug, as well as a more expensive alternative, with no luck.

This is the latest hit for heart medication availability in the country. Nitroglycerin has been in short supply for months.

Dr. Steve Tilley first learned about the dipyridamole shortage in mid-June. Now his Red Deer clinic is also out.

“A lot of patients are in a bit of limbo,” he said.

“We unfortunately tell them that there are symptoms that may very well be related to blockages in the arteries in the heart. But we unfortunately have no way of giving them that information until the supply … improves.”

Tilley, who is the department chair for cardiology at the Alberta Medical Association, said he heard from colleagues in the province with similar issues.

According to Tilley, most of these scans (he estimates 80 to 90 percent) are done privately in Alberta, through community clinics.

“We have no word from the supplier when more is coming… And the tests that need to be done are piling up.”

Dr. Tim Boyne, a cardiologist and the director of nuclear cardiology at TotalCardiology, said his Calgary clinic is receiving about half of its usual supply and he expects waiting lists to grow for some patients.

“We’re trying to reduce our consumption. We’ve asked the hospital if they have excess equipment they can share and they’re unfortunately facing the same predicament as we are.”

According to Boyne, there are several reasons patients may not be candidates for a traditional cardiac stress test, including the inability to walk on a treadmill due to mobility issues and a heart condition that can cause false results.

One option, he said, is to send patients to hospitals for testing, because those facilities have access to a variety of drugs.

“Their waiting lists will also be adversely affected.”

Alberta Health Services said it is monitoring the national shortage and has not affected patient care at its facilities.

“AHS is working with Health Canada on mitigation strategies to replenish supply, including an extension of the expiration date and the importation of products authorized overseas,” spokesman Kerry Williamson said in an emailed statement.

“AHS has a well-developed provincial process to manage drug shortages and is doing our best to minimize or completely avoid the impact on patient care.”

In the Drug Shortages Canada database, the pharmaceutical company cites a production stoppage as the reason for the shortfall and lists the estimated end date as August 18.

It puts patients at risk,” said Dr. Surinder Khinda, an internist and director of Alberta Cardiology and Medical Consultants in Edmonton.

He said patients are often referred to the clinic from the emergency room for myocardial perfusion testing.

“People who have chest pain may have undiagnosed blockages or coronary artery disease. It puts them at risk for a heart attack.”

CBC News reached out to Health Canada for comment, but did not hear back prior to publication.

Meanwhile, Kapoor is frustrated that his patients are once again experiencing a shortage of an important heart drug.

“It’s quite embarrassing as a country, as a G7 country, we struggle to give our citizens – our taxpayers – medicines on time,” he said.