'Old, Frail Patients: Study More, Intervene Less?' Again

 The ability to save cardiac muscle during an acute coronary syndrome with percutaneous coronary intervention (PCI) made cardiology one of the most popular fields in medicine.

But acute coronary syndromes come in different categories. While rapid PCI clearly benefits patients with ST-segment elevation myocardial infarction (STEMI), the best use of angiography and PCI for patients with non–ST-segment elevation myocardial infarction (NSTEMI) is more complex.

The evidence for early invasive vs conservative strategies in patients with NSTEMI is mixed. There have been many trials and meta-analyses, and generally, outcomes are similar with either approach. Perhaps if one looks with enough optimism, there is a benefit for the more aggressive approach in higher-risk patients.

Despite the similar outcomes with the two strategies, most patients are treated with the early invasive approach. Early and invasive fit the spirit of modern cardiology.

Yet, older patients with acute coronary syndromes present a different challenge. NSTEMI trials, like most trials, enrolled mostly younger adults. 

Whether evidence obtained in young people applies to older patients is one of the most common and important questions in all of medical practice. Older patients may be at higher risk for a primary outcome, but they also have greater risks for harm from therapy as well as more competing causes of morbidity and mortality. 

Only a handful of smaller trials have enrolled older patients with NSTEMI. These trials have produced little evidence that an early invasive approach should be preferred. 

The SENIOR-RITA Trial 

At ESC, Vijay Kunadian, MD, from Newcastle, United Kingdom, presented results of SENIOR-RITA, a large trial comparing an invasive vs conservative strategy in NSTEMI patients 75 years of age or older. 

In the conservative arm, coronary angiography was allowed if the patient deteriorated and the procedure was clinically indicated in the judgment of the treating physicians.

Slightly more than 1500 patients with NSTEMI were randomly assigned to either strategy in 48 centers in the UK. Their mean age was 82 years, nearly half were women, and about a third were frail. 

Over 4 years of follow-up, the primary outcome of cardiovascular (CV) death or MI occurred at a similar rate in both arms: 25.6% vs 26.3% for invasive vs conservative, respectively (HR, 0.94; 95% CI, 0.77-1.14; P =.53). 

Rates of CV death were also not significantly different (15.8% vs 14.2%; HR, 1.11; 95% CI, 0.86-1.44). 

The rate of nonfatal MI was slightly lower in the invasive arm (11.7% vs 15.0%; HR, 0.75; 95% CI, 0.57-0.99)

Some other notable findings: Less than half of patients in the invasive arm underwent revascularization. Coronary angiography was done in about a quarter of patients in the conservative arm, and revascularization in only 14%. 

Comments

Because medicine has improved and patients live longer, cardiologists increasingly see older adults with frailty. It's important to study these patients. 

The authors tell us that 1 in 5 patients screened were enrolled, and those not enrolled were similar in age and were treated nearly equally with either strategy. Not all trials offer this information; it's important because knowing that patients in a trial are representative helps us translate evidence to our actual patients. 

Another positive was the investigators' smart choice of cardiovascular death and MI as their primary outcome. Strategy trials are usually open label. If they had included an outcome that requires a decision from a clinician, such as unplanned revascularization, then bias becomes a possibility when patients and clinicians are aware of the treatment assignment. (I wrote about poor endpoint choice in the ABYSS trial.) 

The most notable finding in SENIOR-RITA was that approximately 76% of patients in the conservative arm did not have a coronary angiogram and 86% were not revascularized. 

Yet, the rate of CV death and MI were similar during 4 years of follow-up. This observation is nearly identical to the findings in chronic stable disease, seen in the ISCHEMIA trial. (See Figure 6a in the paper's supplement.) 

I take two messages from this consistent observation: One is that medical therapy is quite good at treating coronary artery disease not associated with acute vessel closure in STEMI. 

The other is that using coronary angiography and revascularization as a bailout, in only a fraction of cases, achieves the same result, so the conservative strategy should be preferred.

I am not sure that the SENIOR RITA researchers see it this way. They write in their discussion that "clinicians are often reluctant to offer an invasive strategy to frail older adults." They then remind readers that modern PCI techniques (radial approach) have low rates of adverse events. 

Perhaps I misread their message, but that paragraph seemed like it was reinforcing our tendency to offer invasive approaches to patients with NSTEMI. 

I feel differently. When a trial reports similar outcomes with two strategies, I think we should favor the one with less intervention. I feel even more strongly about this philosophy in older patients with frailty.

Are we not in the business of helping people with the least amount of intervention?

The greatest challenge for the cardiologist of today is not a lack of treatment options, but whether we should use all options in older, frailer adults. 

Good on the SENIOR-RITA investigators, for they have shown that we can avoid intervention in the vast majority of older adults presenting with NSTEMI. 

John Mandrola practices cardiac electrophysiology in Louisville, Kentucky, and is a writer and podcaster for Medscape. He espouses a conservative approach to medical practice. He participates in clinical research and writes often about the state of medical evidence. 

https://www.medscape.com/viewarticle/old-frail-patients-study-more-intervene-less-2024a1000fzp