Xuming Dai

Genetics of coronary artery disease and myocardial infarction

Atherosclerotic coronary artery disease (CAD) comprises a broad spectrum of clinical entities that include asymptomatic subclinical atherosclerosis and its clinical complications, such as angina pectoris, myocardial infarction (MI) and sudden cardiac death. CAD continues to be the leading cause of death in industrialized society. The long-recognized familial clustering of CAD suggests that genetics plays a central role in its development, with the heritability of CAD and MI estimated at approximately 50% to 60%. Understanding the genetic architecture of CAD and MI has proven to be difficult and costly due to the heterogeneity of clinical CAD and the underlying multi-decade complex pathophysiological processes that involve both genetic and environmental interactions. This review describes the clinical heterogeneity of CAD and MI to clarify the disease spectrum in genetic studies, provides a brief overview of the historical understanding and estimation of the heritability of CAD and MI, recounts major gene discoveries of potential causal mutations in familial CAD and MI, summarizes CAD and MI-associated genetic variants identified using candidate gene approaches and genome-wide association studies (GWAS), and summarizes the current status of the construction and validations of genetic risk scores for lifetime risk prediction and guidance for preventive strategies. Potential protective genetic factors against the development of CAD and MI are also discussed. Finally, GWAS have identified multiple genetic factors associated with an increased risk of in-stent restenosis following stent placement for obstructive CAD. This review will also address genetic factors associated with in-stent restenosis, which may ultimately guide clinical decision-making regarding revascularization strategies for patients with CAD and MI.

Association of inpatient vs outpatient onset of ST-elevation myocardial infarction with treatment and clinical outcomes.

IMPORTANCE Reperfusion times for ST-elevation myocardial infarction (STEMI) occurring in outpatients have improved significantly, but quality improvement efforts have largely ignored STEMI occurring in hospitalized patients (inpatient-onset STEMI). OBJECTIVE To define the incidence and variables associated with treatment and outcomes of patients who develop STEMI during hospitalization for conditions other than acute coronary syndromes (ACS). DESIGN, SETTING, AND PARTICIPANTS Retrospective observational analysis of STEMIs occurring between 2008 and 2011 as identified in the California State Inpatient Database. EXPOSURES STEMIs were classified as inpatient onset or outpatient onset based on present-on-admission codes. Patients who had a STEMI after being hospitalized for ACS were excluded from the analysis. MAIN OUTCOMES AND MEASURES Regression models were used to evaluate associations among location of onset of STEMI, resource utilization, and outcomes. Adjustments were made for patient age, sex, comorbidities, and hospital characteristics. The analysis allowed for the location of inpatient STEMI to have a multiplicative rather than an additive effect for resource utilization since these measures were highly skewed. RESULTS A total of 62,021 STEMIs were identified in 303 hospitals, of which 3068 (4.9%) occurred in patients hospitalized for non-ACS indications. Patients with inpatient-onset STEMI were older (mean, 71.5 [SD, 13.5] years vs 64.9 [SD, 14.1] years; P < .001) and more frequently female (47.4% vs 32%; P < .001) than those with outpatient-onset STEMI. Patients with inpatient-onset STEMI had higher in-hospital mortality (33.6% vs 9.2%; adjusted odds ratio (AOR), 3.05; 95% CI, 2.76-3.38; P < .001), were less likely to be discharged home (33.7% vs 69.4%; AOR, 0.38; 95% CI, 0.34-0.42; P < .001), and were less likely to undergo cardiac catheterization (33.8% vs 77.8%; AOR, 0.19; 95% CI, 0.16-0.21; P < .001) or percutaneous coronary intervention (21.6% vs 65%; AOR, 0.23; 95% CI, 0.21-0.26; P < .001). Length of stay and inpatient charges were higher for inpatient-onset STEMI (mean length of stay, 13.4 days [95% CI, 12.8-14.0 days] vs 4.7 days [95% CI, 4.6-4.8 days]; adjusted multiplicative effect, 2.51; 95% CI, 2.35-2.69; P < .001; mean inpatient charges,

Acute ST-Elevation Myocardial Infarction in Patients Hospitalized for Noncardiac Conditions

245,000 [95% CI,

Predictors, treatment, and outcomes of STEMI occurring in hospitalized patients

235,300-

Factors Associated With Ineligibility for PCI Differ Between Inpatient and Outpatient ST‐Elevation Myocardial Infarction

254,800] vs

In-Hospital ST-Segment Elevation Myocardial Infarction: Improving Diagnosis, Triage, and Treatment

129,000 [95% CI,

Clinical Evidence Supports a Protective Role for CXCL5 in Coronary Artery Disease

127,900-

A Quality Improvement Program for Recognition and Treatment of Inpatient ST-Segment Elevation Myocardial Infarctions

130,100]; adjusted multiplicative effect, 2.09; 95% CI, 1.93-2.28; P < .001). CONCLUSIONS AND RELEVANCE Patients who had a STEMI while hospitalized for a non-ACS condition, compared with those with onset of STEMI as an outpatient, were less likely to undergo invasive testing or intervention and had a higher in-hospital mortality rate.

In-Hospital ST Elevation Myocardial Infarction Clinical Characteristics, Management Challenges, and Outcome

Background Major advances have been made in the treatment of ST‐elevation myocardial infarction (STEMI) in outpatients. In contrast, little is known about outcomes in STEMI that occur in patients hospitalized for a noncardiac condition. Methods and Results This was a retrospective, single‐center study of inpatient STEMIs from January 1, 2007, to July 31, 2011. Forty‐eight cases were confirmed to be inpatient STEMIs of a total of 139 410 adult discharges. These patients were older and more often female and had higher rates of chronic kidney disease and prior cerebrovascular events compared with 227 patients with outpatient STEMIs treated during the same period. Onset of inpatient STEMI was heralded most frequently by a change in clinical status (60%) and less commonly by patient complaints (33%) or changes on telemetry. Coronary angiography and percutaneous coronary intervention were performed in 71% and 56% of patients, respectively. The median time to obtain ECG (41 [10, 600] versus 5 [2, 10] minutes; P<0.001), ECG to angiography time (91 [26, 209] versus 35 [25, 46] minutes; P<0.001) and ECG to first device activation (FDA) (129 [65, 25] versus 60 [47, 76] minutes; P<0.001) were longer for inpatient versus outpatient STEMI. Survival to discharge was lower for inpatient STEMI (60% versus 96%; P<0.001), and this difference persisted after adjusting for potential confounders. Conclusions Patients who develop a STEMI while hospitalized for a noncardiac condition are older and more often female, have more comorbidities, have longer ECG‐to‐FDA times, and are less likely to survive than patients with an outpatient STEMI.

Correlation of infarct size with invasive hemodynamics in patients with ST-elevation myocardial infarction

ST-segment elevation myocardial infarction (STEMI) is most commonly caused by an acute thrombotic occlusion of a coronary artery. For patients in whom the onset of STEMI occurs outside of hospital (outpatient STEMI), early reperfusion therapy with either fibrinolysis or primary percutaneous coronary intervention reduces complications and improves survival, compared with delayed reperfusion. STEMI systems of care are defined as integrated groups of separate entities focused on reperfusion therapy for STEMI, generally including emergency medical services, emergency medicine, cardiology, nursing, and hospital administration. These systems of care have been successful at reducing total ischaemia time and outpatient STEMI mortality. By contrast, much less is known about STEMI that occurs in hospitalized patients (inpatient STEMI), which has unique clinical features and much worse outcomes than outpatient STEMI. Inpatient STEMI is associated with older age, a higher female:male ratio, and more comorbidities than outpatient STEMI. Delays in diagnosis and infrequent use of reperfusion therapy probably also contribute to unfavourable outcomes for inpatient STEMI.