Patients are regularly having to wait a year and a half for heart scans that could tell them whether they have a serious or life-threatening condition.
Echocardiograms are an ultrasound for the heart, a non-invasive test that can show blockages and other damage.
Long waits have been causing concern for years but have blown out to unprecedented levels.
General practitioner and medical director of the College of GPs Luke Bradford said it was creating anxiety for many patients.
"It ranges from bemusement to a sense of fear that there is a long wait.
"And, that sense of unknowing is very disturbing for patients, a sense that they don't have a handle on what is happening with their heart and where that may go."
West Auckland woman Allison Oosterman had a series of tests in February after some fainting spells.
She had great care in the hospital but had not heard anything until last week when she got a letter saying she needed an echocardiagram.
The form letter said she would have to wait longer than recommended because of very high demand, possibly over 12 months.
It said she could pay herself to go privately, or through an insurer, an option Oosterman was taking up.
"If I didn't have the insurance - I'm under a lot of stress now anyway - I would be beside myself, I really would be."
She worried about those not in the position to do that.
Most of those waiting a year or more were deemed at low risk of serious illnesses.
Professor of sonography at Otago University Gillian Whalley was one of many registered cardiac sonographers pulling extra weekend work to try to get people scanned.
"For most of them it won't really affect their care, but for a small, critical number of them it might mean a delay in getting evidence-based life saving medicines or treatment."
A small number of patients had waited two or three years, she said.
RNZ asked each Te Whatu Ora district last Wednesday what their wait was but had no answers yet.
Several clinicians spoken to said 18 months was standard in many parts of the country but those with urgent conditions were usually seen within six to eight weeks.
GP Luke Bradford said it was good that urgent cases were being triaged.
"But the wait times even for those is higher than the profession would like to see."
Te Whatu Ora's letter to patients told them they would be contacted when it was time for them to get their scan and to contact their GP if their health or symptoms got worse.
Gillian Whalley said it was important patients did not think 'she'll be right' and that every thing must be okay if they had been waiting a long time - they should get in touch with their doctor if they were worried about their health.
The reasons behind the growing waits were complex, she said.
COVID did not help but the problem had existed before that, and there were many factors at play.
That included a wider range of people who needed echocardiograms, including some cancer patients at risk of heart damage from chemotherapy.
Training new cardiac sonographers was complex and expensive, with most already qualified in other areas and retraining on the job.
"It's a very highly specialised workforce and we haven't trained enough people and we've known that for about ten years or so."
Whalley was optimistic Te Whatu Ora was taking the problem seriously, with work underway to develop a new undergraduate training programme.
RNZ
