PARIS, France—Japanese patients with acute coronary syndromes (ACS) have very good in-hospital and 1-year outcomes, likely due to routine treatment with percutaneous coronary intervention (PCI) and optimal medical therapy, according to a large registry analysis presented August 29, at the European Society of Cardiology Congress 2011.

And in a comparison with Western patients, Japanese patients demonstrated better outcomes, reported Katsumi Miyauchi, MD, of Juntendo University (Tokyo, Japan).

Dr. Miyauchi and colleagues performed a large prospective cohort study evaluating recurrent cardiovascular events over 1 year in 3,596 ACS patients from 96 Japanese core hospitals enrolled in the PACIFIC (Prevention of AtherothrombotiC Incidents Following Ischemic Coronary attack) registry between May 2008 and May 2009.

In the overall ACS population, 59% had STEMI, 10% NSTEMI, and 30% unstable angina. The average age was 67 and about three-quarters were men: 73% had hypertension, 67% dyslipidemia, 34% chronic kidney disease, and 35% diabetes. Diabetes and dyslipidemia tended to be higher in unstable angina patients.

PCI Routine for All ACS Patients

Remarkably, 94% of the entire cohort received PCI, including 96% of STEMI patients, 89% of NSTEMI patients, and 91% of unstable angina patients.

By hospital discharge, 3.0% of patients had experienced the primary endpoint of MACCE (composite of death, nonfatal MI, and nonfatal stroke) and 1.9% had died. MACCE rates were significantly higher for STEMI and NSTEMI patients than for unstable angina patients (4.1% and 3.2%, respectively, vs.0.8%; P < 0.0001). The same pattern was seen for mortality (2.7% for STEMI and 1.3% for NSTEMI vs. 0.5% for unstable angina; P < 0.0001).

At discharge, the great majority of patients were receiving antiplatelet therapy as well as evidence-based medications including an ACE inhibitor/angiotensin receptor blocker (ARB), beta blocker, calcium antagonist, and statin. Over 1 year, systolic blood pressure decreased from 135 mm Hg at discharge to 129 mm Hg, while LDL declined from 122 mg/dL to 90 mg/dL, bringing these parameters within goal range.

Low 1-Year Outcomes

At 1 year, rates of MACCE and all-cause mortality remained low, and there was no longer a difference between STEMI/NSTEMI patients and unstable angina patients (P = 0.86 for MACCE; P = 0.37 for all-cause mortality; table 1).

Table 1. Major 1-Year Outcomes

Analysis revealed several predictors of 1-year MACCE:

• Prior history of CABG (HR 3.11; P = 0.022)
• eGFR less than 30 mL/min/1.73 m² (HR 1.96; P = 0.029)
• Age greater than 75 years (HR 2.16; P < 0.001)
• CRP greater than 0.3 mg/dL (HR 1.49; P = 0.042)
• Prior history of MI (HR 2.46; P < 0.0001)

Predictors of 1-year mortality were:

• eGFR less than 60 mL/min/1.73 m² (HR 3.15; P < 0.0001)
• Age greater than 65 years (HR 3.40; P = 0.001)
• PAD (HR 3.91; P < 0.0001)
• Smoking, current or past (HR 2.00; P = 0.009)

Victory in the PACIFIC

Dr. Miyauchi then compared the Japanese PACIFIC data to those from the GRACE (Global Registry of Acute Coronary Events) database, which tracks ACS in 30 countries (most of them Western), highlighting differences in patient population, treatments, and outcomes.

The 2 registries differ notably in the distribution of the types of ACS. STEMI accounted for 59% of PACIFIC patients but only 34% of GRACE patients, while the prevalence of NSTEMI was 10% in PACIFIC and 29% in GRACE; rates of unstable angina, on the other hand, were similar: 30% for PACIFIC and 31% for GRACE.

In terms of baseline characteristics, Japanese patients had a higher incidence of diabetes and hypertension but were less likely to have a history of angina.

The likelihood of intervention also differed strikingly between the 2 registries: 94% of PACIFIC patients underwent PCI, while one-third of GRACE patients received the procedure. CABG, meanwhile, was performed in only 2% of Japanese patients vs. 6% of GRACE patients. At discharge, PACIFIC patients were more likely to receive ACE/ARBs and statins but not beta-blockers.

In terms of outcome, Japanese patients fared better than GRACE patients for both in-hospital and long-term mortality across the spectrum of ACS (tables 2 and 3).

Table 2. In-Hospital Mortality

Table 3. Long-term Mortality

Miyauchi K. The PACIFIC registry: One-year follow-up data of a 2-year study in patients initially hospitalized with ACS. Presented at: European Society of Cardiology Congress; August 29, 2011; Paris, France.

Disclosures:

• Dr. Miyauchi reports receiving funding support from Sanofi-Aventis.