New era of left main coronary artery treatment strategy

Differences in initial electrocardiographic findings between ST-elevation myocardial infarction due to left main trunk and left anterior descending artery lesions

Background

Early discrimination of ST-elevation myocardial infarction (STEMI) due to a left main trunk (LMT) lesion provided by straightforward electrocardiographic criteria is useful for prompt treatment. The purpose of this study is to investigate differences in electrocardiographic findings between STEMI due to lesions of LMT and those of left anterior descending artery (LAD).

Methods

Initial electrocardiogram (ECG) recordings of 435 patients with analyzable ECGs from a cohort of 940 consecutive STEMI patients were analyzed retrospectively for presence of LMT lesions (LMT, n = 39), proximal (pLAD, n = 224) and distal LAD lesions (dLAD, n = 172). ST-segment deviations in 12 leads were assessed among 3 groups without bundle branch block (n = 17 in LMT, n = 180 in pLAD, and n = 159 in dLAD).

Results

Magnitudes of ST-segment deviations showed significant differences in leads II, III, aVR aVL, aVF, and V2–V6 across the three groups. This difference suggested two possible characteristic findings in the LMT group, allowing it to be distinguished from the pLAD or dLAD group; (A) larger magnitude of ST-segment depression in lead II than that of ST-segment elevation in lead V2 (47.1% in LMT vs. 0.6% in pLAD vs. 1.3% in dLAD, P < 0.0001), and (B) ST-segment depression in lead V5 (58.8% in LMT vs. 6.7% in pLAD vs. 2.5% in dLAD, P < 0.0001). These findings exhibited superior negative predictive value over conventional ST-segment elevation in lead aVR.

Conclusions

A large reciprocal ST-segment depression in inferior leads and ST-segment depression in lead V5 are useful ECG findings allowing determination of STEMI due to an LMT lesion.

Enhancing Angiogenesis in Mice by VEGF-Targeting Small Activating RNAs

The prevalence of cardiovascular diseases is steadily increasing, and it is the leading cause of death worldwide. Therefore, new treatments, such as gene therapy are needed. During the last decade, the role of small noncoding RNAs (ncRNAs) in the regulation of gene expression at the transcriptional level has been shown. Promoter-targeted small RNAs recruit histone-modifying enzymes and can either repress or induce target gene expression. As an example, we have targeted mouse VEGF-A promoter with small hairpin RNAs (shRNAs) and identified two shRNAs which either repressed or induced VEGF-A expression on messenger RNA and protein level in vitro, depending on the targeted location. The changes in expression levels correlate with changes in the levels of epigenetic markers, such as histone modifications associated with repressed or active state of chromatin. In ischemic mouse hindlimbs, upregulation of VEGF-A expression increased vascularity and blood flow. When VEGF-A was upregulated in mouse myocardial infarction model, the blood vessel formation in the risk zone was observed and infarct size was significantly decreased already 2 weeks after treatment. We suggest that epigenetic upregulation of VEGF-A by ncRNAs can be transferred to clinical use for the treatment of ischemic diseases in the near future.

Outcome after Elective Percutaneous Coronary Intervention Depends on Age in Patients with Stable Coronary Artery Disease - An Analysis of Relative Survival in a Multicenter Cohort and an OCT Substudy

Background

Age is a strong predictor of survival in patients with coronary artery disease. In elder patients with increasing co-morbidities percutaneous coronary intervention (PCI) is associated with more complications and worse outcome. The calculation of relative survival rates adjusts for the “background” mortality in the general population by correcting for age and gender. We analyzed if elder patients after elective PCI have a worse relative survival compared to younger patient groups.

Methods

A total of 8,342 patients who underwent elective PCI at two high volume centers between 1998 and 2009 were analyzed.

Results

The survival of our patients after PCI (observed survival) was slightly lower compared to the general population (expected survival) resulting in a slightly decreasing relative survival curve. In a multivariate Cox regression model age amongst others was a strong predictor of survival. Stratifying patients according to their age the relative survival curves of younger patients (Quartile 1: <58 years; 2,046 patients), elder patients (Quartile 3: 66–73 years; 2,090 patients) and very old patients (Quartile 4: >73 years; 2,307 patients) were similar. The relative survival of mid-aged patients (Quartile 2: 58–65 years; 1,899 patients) was better than that of all other patient groups. The profile of cardiovascular risk factors differs between the various groups resulting in different composition and burden of coronary plaques in an optical coherence tomography sub-study.

Conclusion

Patients after elective PCI have a slightly worse long-term survival compared to the age- and sex-matched general population. This is also true for different groups of age except for mid-aged patients between 58 and 63 years. Elder patients between 66 and 73 years and above 73 years have a similar relative survival compared to younger patients below 58 years, and might therefore have similar benefit from elective PCI.