Half of heart attack patients fail to immediately call an ambulance for help, delaying diagnosis and potentially worsening their survival odds, reports Reuters Health.
Swedish researchers studied treatment timelines from symptom onset to diagnosis for about 450 people hospitalised for the deadliest type of heart attacks, known as ST-elevation myocardial infarction (STEMI), which are caused by prolonged blockage of blood supply to the heart.
Patients who called an ambulance right away were typically diagnosed about 81 minutes after symptoms started, a timeline that stretched to 119 minutes for people who found another way to the hospital or made other calls first.
"I think many patients simply may not realise how critical immediate interventions are in treating ST-elevation myocardial infarction, and denial of the potential severity of their symptoms may also contribute to a delay in seeking medical help," Dr Christopher Lee, an emergency medicine researcher at Yale University School of Medicine in New Haven, Connecticut, said.
In any heart attack, a coronary artery is at least partially blocked by a blood clot or arterial plaque. With STEMI, the artery is completely blocked, causing the heart muscle supplied by that vessel to start dying. Symptoms can include chest pain, heart palpitations, sweating, dizziness and nausea, and diagnosis is confirmed with an electrocardiogram (ECG). For some patients, treatment can start in an ambulance with clot-busting drugs. At the hospital, doctors typically insert a catheter in the groin and snake it through the damaged artery, then deploy a tiny balloon to open the passage. Surgeons may also place a wire mesh cage known as a stent in the vessel to prevent future blockage.
The study by Ingela Thylen of Linkoping University in Sweden and colleagues found that 83% of patients eventually took an ambulance to the hospital. But one in five called a healthcare hotline first, and another 14% either called their primary care provider before the emergency services or went directly to the emergency room themselves.
Among patients who didn't immediately call emergency medical services, 40% said they thought they could get to the hospital faster on their own, 30% didn't think they were sick enough to go to the hospital and 25% thought it was easier to be driven or take a taxi.
Women were less likely to call an ambulance than men, and people with more education or a history of diabetes were also less inclined to contact emergency medical services. When pain was not very intense, or involved the neck, that was also associated with a lower likelihood of calling an ambulance first. People were more likely to call an ambulance immediately if they had a history of heart attacks, abnormal heart rhythms, abdominal pain or a belief that their symptoms originated in their heart.
The Swedish study is small, and it can't prove that delaying the call for an ambulance stalls diagnosis and treatment, it can only show that the two are connected, the researchers note.
[link url="http://www.reuters.com/article/2015/05/07/us-heart-attack-call-choices-idUSKBN0NS1TD20150507"]Full Reuters Health report[/link]
[link url="http://bmjopen.bmj.com/content/5/4/e007059.full"]BMJ Open abstract[/link]