Heart attack treatment - SENIOR-RITA

The clinical question

Every year, thousands of people are admitted to hospital in the UK with a suspected non-ST-segment elevation myocardial infarction (NSTEMI) heart attack – where the coronary arteries that supply the heart with blood are severely narrowed but not completely blocked. Currently, guidelines recommend that people with NSTEMI who are considered at risk of further problems related to their heart's blood supply have an invasive coronary angiogram within 72 hours. Here, a small tube (a catheter) is inserted into an artery and guided up to the heart, allowing doctors to look inside the coronary arteries to check for narrowing or blockages and open up the arteries if required to restore blood flow (revascularisation). While this procedure is usually straightforward, complications can include bleeding and strokes. Older people with NSTEMI are less likely to be offered this invasive treatment. The alternative is to treat people admitted with NSTEMI with the best available drug treatments. 

Despite NSTEMI being the main type of heart attack in people older than 75 years, most previous clinical trials of NSTEMI treatment did not enrol older patients - so it was unclear if the same treatment rules hold true for older people. Professor Vijay Kunadian and her team led from Newcastle University were determined to find out. Funded by British Heart Foundation, they designed the SENIOR-RITA trial to find out if older, frail patients with NSTEMI could benefit from a routine invasive approach, consisting of angiography and possible revascularisation plus the best available drug treatments, compared with a ‘conservative approach’ of best available drug treatment (optimal medical therapy).

What did the study involve?

Between 2016 and 2023, the trial team recruited over 1500 patients admitted to hospital with NSTEMI aged 75 years or older from 48 centres across the UK. The average age of the participants was 82 years. Nearly half were women and about a third were frail. The oldest patient in the trial was 103 years old. Most participants had at least one other long-term illness, for example, high blood pressure, diabetes or kidney disease. 

The participants were randomly split into two groups (trial arms):

• The group assigned to an ‘invasive strategy’ had a coronary angiography and revascularisation if required, plus the best possible medication. Around half of the participants in the invasive strategy arm ended up having a revascularisation.
• The other group were managed with a ‘conservative approach’. They were given the best possible medication to treat the heart attack and had an angiogram only if their symptoms did not improve or became worse.

The trial was disrupted by the Covid-19 pandemic, which made recruiting older, frail patients even more challenging. Because of these difficulties, the trial stopped recruiting with fewer participants than originally planned. 

What did the study show?

• Over 4 years of follow-up, similar numbers of participants in each trial arm had either another heart attack or died from a cardiovascular cause (25.6% [193 patients] in the invasive arm versus 26.3% [201 patients] in the conservative arm). 
• Less people in the invasive arm had another heart attack compared with the conservative arm (11.7% [88 patients] vs 15% [115 patients]).
• The risk of dying from any cause (either cardiovascular or a cause unrelated to cardiovascular disease) was similar in both arms. 
• In people who had revascularisation, bleeding and procedure-related complications were minimal (<1%)
• More people treated conservatively had to return to hospital for revascularisation compared with those in the invasive arm (105 patients [13.7%] in the conservative arm compared with 29 patients [3.9%] in the invasive arm). 

Why is the study important?

Older, frail people with multiple long-term illnesses are often excluded from clinical trials. The SENIOR-RITA team set out to change that. Despite the challenges posed by the Covid-19 pandemic and the frailty of the patient population, the trial team managed to recruit large numbers of older patients and follow them up for a long time, making SENIOR-RITA the largest and longest study of its kind. 

Professor Kunadian explained the importance of the trial’s findings for patient care: “SENIOR-RITA provides guidance to clinicians and patients to make an informed decision about whether or not to undergo invasive treatment for NSTEMI heart attack. The trial showed that having an invasive procedure doesn’t save lives, but prevents patients from being admitted back to hospital with another heart attack or for further repeat procedures. The trial also showed that angiography is safe in older patients.”

Professor Kunadian and the University of Newcastle team won the Clinical Research Excellence Award at the Global Cardiovascular Awards in March 2025 for their successful delivery of SENIOR-RITA. The awards recognise those at the forefront of improving how cardiovascular disease is treated.

Professor Kunadian concluded: “The study was the first time this group of patients had been studied in such detail. I’d like to take this opportunity to thank everyone who was involved in making the study a success, and particularly to the many patients who took part."

The participant voice

Joan was one of the 1518 people who took part in SENIOR-RITA. Hear her story in the video below.

Study details

"The older patients Randomised Interventional Trial in Acute non-st elevation myocardial infarction: the SENIOR-RITA trial”
Award reference: CS/15/7/31679
Principal Investigator: Professor Vijay Kunadian, Newcastle University
Trial registration number: ISRCTN11343602

Publication details

Kunadian V et al. Invasive Treatment Strategy for Older Patients with Myocardial Infarction. N Engl J Med. 2024; 391 (18): 1673-1684.

Video summary of the trial from the NEJM