Study Investigates Which Elderly Patients Benefit from Aggressive Treatment

PARIS, France—Among very elderly patients with non-ST-segment acute coronary syndromes (NSTE ACS), early aggressive treatment appears to improve results over an initially conservative strategy. But the trend reaches statistical significance only in those who also have elevated troponin, according to results presented at this year’s European Society of Cardiology Congress on Monday, August 29, 2011.

For the 23-center Italian Elderly ACS Study, researchers led by Stefano Savonitto, MD, of Ospedale Niguarda Cà Granda (Milan, Italy), prospectively enrolled 313 NSTE ACS patients who were aged at least 75 years and showed symptoms suggestive of acute MI within the past 48 hours. Subjects were randomized to either early aggressive (n = 154) or initially conservative treatment (n = 159). Early aggressive treatment was defined as angiography within 72 hours, while patients initially treated conservatively received angiography in the event of evidence of refractory ischemia.

Mean patient age was 81.8 years in both treatment arms, and the prevalence of elevated troponin was similar at 62% in the aggressive group and 60% in the conservative group. Most patients had hypertension.

During index admission, higher proportions of the aggressively treated patients underwent angiography (88% vs. 29%) and any revascularization (55% vs. 23%). The pattern held true at 1-year follow-up, with 58% of the aggressive group having undergone either PCI or CABG compared with 31% of the conservative group.

Among those who underwent revascularization, the median time to treatment was much shorter in the aggressive group (24 hours, interquartile range [IQR] 15-46 hours) than in the conservative group (67 hours, IQR 24-113 hours). Radial access was common in both groups at 70% and 78%, respectively.

Outcomes Vary by Strategy, Troponin

Conservatively treated patients were more likely than their aggressively treated peers to experience severe recurrent ischemia during index hospitalization (9.4% vs. 0.6%; P = 0.004) but less likely to have heart failure (2.5% vs. 71%; P = 0.06).

At 1 year, the primary composite endpoint—all-cause mortality, MI, disabling stroke, and rehospitalization for cardiovascular causes or severe bleeding—was numerically higher in the conservative group, as were each of the component endpoints (table 1).

Table 1. Cumulative Outcomes at 1 Year

The difference was more pronounced in those with elevated troponin levels, where the aggressive strategy produced a 22% event rate and the conservative strategy resulted in a 40% event rate. Subgroup analysis confirmed that patients with elevated troponin levels at baseline had significantly lower risk of the primary endpoint with the early aggressive strategy vs. the initially conservative strategy (HR 0.43; 95% CI 0.23-0.80; P = 0.03).

Thus, the trial met its primary endpoint only in patients with elevated troponin, Dr. Savonitto pointed out.

Radial Access Key

According to Dr. Savonitto, one reason why aggressive treatment worked so well even in very elderly NSTE ACS patients may be the researchers’ preference for the radial approach. “We did 70% of our angiography procedures via the radial approach, using the wrist, not the femoral approach, which is more common in the United States. With the radial approach, there is much less risk of bleeding and complications,” he said, adding that the researchers had very few bleeding problems in the trial.

Nonetheless, the advantage for early aggressive treatment was only significant among patients with elevated troponin. “In patients with normal troponin, [it] had no effect,” Dr. Savonitto stressed.

The researchers are planning a subsequent trial on elderly patients that will begin enrolling next spring, he reported.