Comparison of long-term outcomes between older Asian and white patients with non-ST-segment elevation myocardial infarction: findings from CRUSADE-CMS database

Impact of Race/Ethnicity on Long Term Outcomes After Percutaneous Coronary Intervention with Drug-Eluting Stents

Cardiovascular disease constitutes the leading cause of mortality worldwide, irrespective of race/ethnicity. Previous studies have shown that minority patients with acute coronary syndrome have distinct clinical, anatomic, and socioeconomic characteristics which may affect clinical outcomes. We included patients who underwent percutaneous coronary intervention with drug-eluting stents for ST-segment elevation myocardial infarction (STEMI), non-STEMI, or unstable angina in a single center. Patients were stratified into Caucasian, African-American, Hispanic, and Asian. Caucasians were the reference group. The primary end point was major adverse cardiac and cerebrovascular events, composite of death, spontaneous myocardial infarction, or stroke at 1 year. Of 6,800 patients included, 49.7% were Caucasian, 20.7% Hispanic, 17.0% Asian and 12.6% African-American. Caucasians were the oldest, Hispanics and Asians had the highest prevalence of diabetes mellitus whereas African-Americans had more chronic kidney disease. Hispanics and African-Americans had the highest STEMI rates, whereas Asians were more likely to present with unstable angina. Compared with Caucasians, Asians had a lower rate of major adverse cardiac and cerebrovascular events at 1 year (3.9% vs 7.1%; p <0.01) whereas Hispanics (6.2% vs 7.1%; p = 0.17) and African-Americans (8.0% vs 7.1%; p = 0.38) had comparable outcomes. Differences were driven by mortality. Findings remained unchanged after adjustment. In conclusion, in acute coronary syndrome patients who underwent percutaneous coronary intervention, Asian race/ethnicity was associated with favorable cardiovascular outcomes compared with Caucasians. No significant differences were observed for Hispanics and African-Americans.

Ethnic Differences in the Pathobiology of Acute Coronary Syndromes Between Asians and Whites

Ethnic differences in the pathobiology of acute coronary syndromes (ACS) have not been systematically studied. We compared the underlying mechanisms of ACS between Asians and Whites. ACS patients with the culprit lesion imaged by optical coherence tomography were included. Patients were stratified into ST-elevation myocardial infarction (STEMI) and non-ST-elevation-ACS (NSTE-ACS), and baseline characteristics, underlying mechanisms of ACS, and culprit plaque characteristics were compared between Asians and Whites. Of 1,225 patients, 1,019 were Asian (567 STEMI and 452 NSTE-ACS) and 206 were White (71 STEMI and 135 NSTE-ACS). Asians had more diabetes and hypertension among STEMI patients; among NSTE-ACS patients, Asians had higher prevalence of diabetes and renal insufficiency, and lower prevalence of hyperlipidemia. There were no differences in the incidence of plaque rupture, plaque erosion and calcified plaque between Asians and Whites with STEMI (61.2%, 28.6%, 10.2% vs 46.5%, 38.0%, 15.5%, respectively, p = 0.055). Among NSTE-ACS patients, there was a significant difference between Asians and Whites (40.5%, 47.6%, 11.9% vs 27.4%, 48.9%, 23.7%, respectively, p = 0.001). After adjustment for clinical confounders, the risk of plaque rupture (p = 0.713), plaque erosion (p = 0.636), and calcified plaque (p = 0.986) was similar between the groups with STEMI. In NSTE-ACS patients, the only difference was an increased risk of calcified plaque in Whites (odds ratio: 2.125, 95% confidence interval: 1.213 to 3.723, p = 0.008). In conclusion, after adjustment for clinical confounders, Asian and White patients presenting with STEMI and NSTE-ACS showed similar underlying mechanisms of ACS, except for a higher risk of calcified plaque in Whites with NSTE-ACS.

Delayed PCI 12 Hours after the Onset of Symptoms Is Associated with Improved Outcomes for Patients with ST-Segment Elevation Myocardial Infarction: A Real-World Study

BACKGROUND

Primary percutaneous coronary intervention (PPCI) plays a pivotal role in the treatment of ST-segment elevation myocardial infarction (STEMI). However, it remains controversial whether PCI delayed beyond the recommended time window of 12 h after the onset of symptoms is applicable to STEMI.

OBJECTIVE

The acute myocardial infarction (AMI) registration study in Xinjiang, China, is a real-world clinical trial (retrospective cohort study) that includes hospitalized patients. The purpose of this study was to compare delayed PCI and medication therapy beyond the recommended time window of 12 h after the onset of symptoms on the outcomes of STEMI patients.

METHODS AND RESULTS

From May 2012 to December 2015, a total of 1072 STEMI patients received delayed PCI (n=594) or standard medication therapy (MT) (n=478) more than 12 h after the onset of symptoms. The number of all-cause deaths in the delayed PCI group and that in the MT group were 55 (9.3%) and 138 (28.9%), respectively, and a significant difference between the groups was indicated for this variable (P<0.001). The number of cardiac deaths in the delayed PCI group and that in the medication therapy group were 47 (7.9%) and 120 (25.1%), respectively, and a significant difference between the groups was indicated for this variable (P<0.001). We also found that the MACE incidence in the delayed PCI group was significantly higher than it was in the MT group (32.2% versus 43.5%, P<0.001). Propensity score matching (PSM) analyses remained significant differences between the delayed PCI group and the MT group, respectively, in all-cause deaths (9.3% versus 25.8%, P<0.001) and cardiac death (8.7% versus 21.6%, P<0.001).

CONCLUSION

Compared to medication therapy, PCI for STEMI delayed beyond 12 h after the onset of symptoms can better reduce mortality and the incidence of MACEs.

TRIAL REGISTRATION

This study is registered with the following: Trial Registration: clinicaltrials.gov; Identifier: NCT02737956.

Racial Differences in Electrocardiographic Characteristics and Prognostic Significance in Whites Versus Asians

Background

Racial differences in electrocardiographic (ECG) characteristics and prognostic significance among Whites and Asians are not well described.

Methods and Results

We studied 2677 White Framingham Heart Study participants (57% women) and 2972 Asian (64% women) Singapore Longitudinal Aging Study participants (mean age 66 years in both) free of myocardial infarction or heart failure. Racial differences in ECG characteristics and effect on mortality were assessed. In linear regression models, PR interval was longer in Asians compared with Whites (multivariable‐adjusted β±SE 5.0±1.4 ms in men and 6.6±0.9 ms in women, both P<0.0006). QT interval was shorter in Asian men (β±SE −6.2±1.2 ms, P<0.0001) and longer in Asian women (β±SE 3.6±0.9 ms, P=0.02) compared to White men and women, respectively. Asians had greater odds of having ECG left ventricular hypertrophy (LVH) compared with Whites (odds ratio [OR] 3.56, 95% confidence interval [CI] 1.36–9.35 for men, OR 1.93, 95% CI 1.35–2.76 for women, both P<0.02). Over a mean follow‐up of 11±3 years in Framingham and 8±3 years in Singapore, mortality rates were 24.5 and 13.4 per 1000 person‐years among Whites and Asians, respectively. In Cox models, the presence of LVH had a greater effect on all‐cause mortality in Asians compared with Whites (hazard ratio [HR] 2.66, 95% CI 1.83–3.88 vs HR 1.30, 95% CI 0.90–1.89, P for interaction=0.02).

Conclusion

Our findings from two large community‐based cohorts show prominent race differences in ECG characteristics between Whites and Asians, and also suggest a differential association with mortality. These differences may carry implications for race‐specific ECG reference ranges and cardiovascular risk.

Hypothesis of Long-Term Outcome after Coronary Revascularization in Japanese Patients Compared to Multiethnic Groups in the US

BACKGROUND

Ethnicity has a significant impact on coronary artery disease (CAD). This study investigated the long-term outcomes of Japanese patients undergoing revascularization compared with US patients belonging to multiple ethnic groups.

METHODS AND RESULTS

We evaluated clinical outcomes, based on ethnicity, of patients included in the Coronary Revascularization Demonstrating Outcome (CREDO-Kyoto) and the Texas (US) Heart Institute Research Database (THIRDBase) registries. For the analysis, we included 8871 patients from the CREDO-Kyoto registry (median follow-up period [FU], 3.5 years; interquartile range [IQR], 2.6-4.3) and 6717 patients from the THIRDBase registry (FU, 5.2 years; IQR, 3.8-6.5) who underwent percutaneous coronary intervention or bypass surgery. Cox proportional hazard models were constructed to compare the adjusted long-term outcomes for each ethnic group. A total of 8871 Japanese, 5170 Caucasians, 648 African-Americans, 817 Hispanics, and 82 Asian-Americans were identified. When adjusted, Japanese patients had significantly better outcomes than US patients, classified by ethnicity (Caucasians: hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.35-1.79; Hispanics: HR, 1.53; 95% CI, 1.22-1.93; African-Americans: HR, 2.03; 95% CI, 1.62-2.56), except for Asian-Americans (HR, 0.84; 95% CI. 0.38-1.89) who had outcomes similar to Japanese patients.

CONCLUSION

Our findings indicate better survival outcomes in re-vascularized Japanese CAD patients compared to major ethnic groups in the US, including Caucasian, Hispanic, and African-American CAD patients. The characteristics and outcomes of Japanese CAD patients were similar to those of Asian-Americans, despite the sample size limitations in the US dataset.

Differential Outcomes by Race and Ethnicity in Patients with Coronary Heart Disease: A Contemporary Review

Coronary heart disease (CHD) is a leading cause of death for people of most ethnicities in the USA. However, several racial and ethnic minority groups are disproportionately burdened by CHD and experience higher mortality rates and rehospitalization rates compared with whites. Contemporary CHD research has been dedicated in part to broadening our understanding of the root causes of racial and ethnic disparities in CHD outcomes. Several factors contribute, including socioeconomic and comorbid conditions. These factors may be amenable to change, and targets for initiatives to reduce disparities and improve CHD outcomes. In this article, we review the recently published research related to the distribution and determinants of racial and ethnic differences in CHD outcomes in the USA.