Reliability and limitations of angiography in the diagnosis of coronary plaque rupture: an intravascular ultrasound study

Role of MIF in myocardial ischaemia and infarction: insight from recent clinical and experimental findings

First discovered in 1966 as an inflammatory cytokine, MIF (macrophage migration inhibitory factor) has been extensively studied for its pivotal role in a variety of inflammatory diseases, including rheumatoid arthritis and atherosclerosis. Although initial studies over a decade ago reported increases in circulating MIF levels following acute MI (myocardial infarction), the dynamic changes in MIF and its pathophysiological significance following MI have been unknown until recently. In the present review, we summarize recent experimental and clinical studies examining the diverse functions of MIF across the spectrum of acute MI from brief ischaemia to post-infarct healing. Following an acute ischaemic insult, MIF is rapidly released from jeopardized cardiomyocytes, followed by a persistent MIF production and release from activated immune cells, resulting in a sustained increase in circulating levels of MIF. Recent studies have documented two distinct actions of MIF following acute MI. In the supra-acute phase of ischaemia, MIF mediates cardioprotection via several distinct mechanisms, including metabolic activation, apoptosis suppression and antioxidative stress. In prolonged myocardial ischaemia, however, MIF promotes inflammatory responses with largely detrimental effects on cardiac function and remodelling. The pro-inflammatory properties of MIF are complex and involve MIF derived from cardiac and immune cells contributing sequentially to the innate immune response evoked by MI. Emerging evidence on the role of MIF in myocardial ischaemia and infarction highlights a significant potential for the clinical use of MIF agonists or antagonists and as a unique cardiac biomarker.

Angiographic characteristics of coronary disease and postresuscitation electrocardiograms in patients with aborted cardiac arrest outside a hospital

Postresuscitation electrocardiogram (ECG) in patients with aborted cardiac death may demonstrate ST-elevation myocardial infarction (STEMI), ST-T changes, intraventricular conduction delay, or other nonspecific findings. In the present study, we compared ECG to urgent coronary angiogram in 158 consecutive patients with STEMI and 54 patients not fulfilling criteria for STEMI admitted to our hospital from January 1, 2003 through December 31, 2008. At least 1 obstructive lesion was present in 97% of patients with STEMI and in 59% of patients without STEMI with ≥1 occlusion in 82% and 39%, respectively (p <0.001). Obstructive lesion was considered acute in 89% of patients with STEMI and in 24% of patients without STEMI (p <0.001). An acute lesion in STEMI had a higher thrombus score (2.6 vs 1.3, p = 0.05) and more often presented with Thrombolysis In Myocardial Infarction grade 0 to 1 flow (75% vs 36%, p <0.01). Percutaneous coronary intervention, which was attempted in 148 lesions in patients with STEMI and in 17 lesions in patients without STEMI, resulted in final Thrombolysis In Myocardial Infarction grade 3 flow in 87% and 71%, respectively (p = 0.34). In conclusion, STEMI on postresuscitation ECG is usually associated with the presence of an acute culprit lesion. However, in the absence of STEMI, an acute culprit lesion is still present in 1/4 of patients. An acute lesion in STEMI is more thrombotic and more often leads to complete occlusion. Urgent percutaneous coronary intervention is feasible and successful regardless of postresuscitation ECG.

Acute coronary angiographic findings in survivors of out-of-hospital cardiac arrest

BACKGROUND

Diagnosis of acute coronary artery disease in survivors of out-of-hospital cardiac arrest (OHCA) is difficult. The role of emergency coronary angiography and percutaneous coronary intervention (PCI) in this setting is debated. The objective of this study was to assess the prevalence of coronary lesions on emergency angiography in survivors of OHCA.

METHODS

Seventy-two consecutive OHCA survivors underwent systematic emergency coronary angiography. Patients with critical stenoses or occlusion underwent ad hoc PCI.

RESULTS

Most (63.9%) OHCA survivors had angiographic coronary artery disease (> or =1 lesion >50%), but only a minority (37.5%) had clinical or angiographic evidence of an acute coronary syndrome due to either an acute occlusion (16.7%) or an irregular lesion suggestive of ruptured plaque or thrombus (25.0%). A final diagnosis of myocardial infarction was assigned in 27 patients (37.5%). Percutaneous coronary intervention was attempted and successful in 33.3% of the total cohort (n = 24). Hospital survival was 48.6%. By multivariable analysis, use of PCI was not an independent correlate of survival. ST-segment elevation on admission was an independent correlate of acute myocardial infarction (odds ratio 64.2, 95% CI 7.6-544.2, P = .0001), with high positive (82.6%) and negative (83.7%) predictive values.

CONCLUSIONS

A minority of OHCA patients has angiographic evidence of an acute coronary syndrome and one-third undergo PCI, but PCI is not an independent correlate of survival. The presence of ST elevation on admission was a strong independent correlate of acute myocardial infarction and may be used to triage OHCA patients to emergency angiography with a view to PCI.