Long-Term Outcomes on Multivessel Disease STEMI Patients

Acute Response of the Noninfarcted Myocardium and Surrounding Tissue Assessed by T2 Mapping After STEMI

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) is associated with a systemic and local inflammatory response with edema. However, their role at the tissue level is poorly characterized.

OBJECTIVES

This study aims to characterize T2 values of the noninfarcted myocardium (NIM) and surrounding tissue and to investigate prognostic relevance of higher NIM T2 values after STEMI.

METHODS

A total of 171 consecutive patients with STEMI without prior cardiovascular events who underwent cardiac magnetic resonance after primary percutaneous coronary intervention were analyzed in terms of standard infarct characteristics. Edema of the NIM, liver, spleen, and pectoralis muscle was assessed based on T2 mapping. Follow-up was available for 130 patients. The primary endpoint was major adverse cardiac events (MACE), defined as cardiovascular death, myocardial infarction, unplanned coronary revascularization or rehospitalization for heart failure. The median time from primary percutaneous coronary intervention to cardiac magnetic resonance was 3 days (IQR: 2-5 days).

RESULTS

Higher (above the median value of 45 ms) T2 values in the NIM area were associated with larger infarct size, microvascular obstruction, and left ventricular dysfunction and did not correlate with C-reactive protein, white blood cells, or T2 values of the pectoralis muscle, liver, and spleen. At a median follow-up of 17 months, patients with higher (>45 ms) NIM T2 values had increased risk of MACE (P < 0.001) compared with subjects with NIM T2 values ≤45 ms, mainly caused by a higher rate of myocardial reinfarction (26.3% vs 1.4%; P < 0.001). At multivariable analysis, higher NIM T2 values independently predicted MACE (HR: 2.824 [95% CI: 1.254-6.361]; P = 0.012).

CONCLUSIONS

Higher NIM T2 values after STEMI are independently associated with worse cardiovascular outcomes, mainly because of higher risk of myocardial infarction.

Assessment of the functional significance of borderline stenosis by determining coronary flow reserve, after primary percutaneous infarct artery intervention by stent implantation

Introduction: Patients with myocardial infarction who are effectively treated with primary percutaneous coronary intervention (PCI) may have significant coronary artery stenosis that is not responsible for current myocardial infarction. Non-infarction artery stenosis can cause serious adverse cardiac events, which can be avoided by performing PCI. Coronary flow reserve (CFR) is defined as the ratio of the hyperemic mean blood flow velocity to the resting blood flow velocity for a given coronary artery. Coronary flow reserve decreases with increasing severity of the lesion. Aim: Determination of CFR prognostic value in patients with residual intermediate stenosis on non-infarcted artery after PCI. Material and methods: The prospective study included 106 patients treated at the University Clinical Center of Serbia in the period from July 2007 to December 2014. Coronary flow reserve was performed on a non-infarcted coronary artery with intermediate stenosis (40-70%). Adenosine was administered intravenously for two minutes to induce hyperemia at a dose of 140 mcg/kg/min. It was calculated as the ratio of the maximum diastolic flow rate under hyperemia and the maximum flow rate under basal conditions. Patients were invited for follow-up at 6, 12, 18, and 24 months to determine the occurrence of composite adverse events, which included: cardiac death, stroke, myocardial infarction, and myocardial revascularization (non-infarction lesion). Results: In our group of patients, 18 adverse events were reported during follow-up. A statistically highly significant difference (p < 0.001) in CFR values was found in patients with adverse events compared to patients without adverse events. The CFR >2 value had a high negative predictive value (95%) for the absence of adverse events. Conclusion: In patients with CFR > 2, revascularization can be safely delayed with continued optimal drug therapy.

Economic evaluation of complete revascularization versus stress echocardiography-guided revascularization in the STEACS with multivessel disease

INTRODUCTION AND OBJECTIVES

Economic studies may help decision making in the management of multivessel disease in the setting of myocardial infarction. We sought to perform an economic evaluation of CROSS-AMI (Complete Revascularization or Stress Echocardiography in Patients With Multivessel Disease and ST-Segment Elevation Acute Myocardial Infarction) randomized clinical trial.

METHODS

We performed a cost minimization analysis for the strategies (complete angiographic revascularization [ComR] and selective stress echocardiography-guided revascularization [SelR]) compared in the CROSS-AMI clinical trial (N=306), attributable the initial hospitalization and readmissions during the first year of follow-up, using current rates for health services provided by our health system.

RESULTS

The index hospitalization costs were higher in the ComR group than in SelR arm (19 657.9±6236.8 € vs 14 038.7±4958.5 €; P <.001). There were no differences in the costs of the first year of follow-up rehospitalizations between both groups for (ComR 2423.5±4568.0 vs SelR 2653.9±5709.1; P=.697). Total cost was 22 081.3±7505.6 for the ComR arm and 16 692.6±7669.9 for the SelR group (P <.001).

CONCLUSIONS

In the CROSS-AMI trial, the initial extra economic costs of the ComR versus SelR were not offset by significant savings during follow-up. SelR seems to be more efficient than ComR in patients with ST-segment elevation acute coronary syndrome and multivessel disease treated by emergent angioplasty. Study registred at ClinicalTrial.gov (Identifier: NCT01179126).

Association of PHACTR1 intronic variants with the first myocardial infarction and their effect on PHACTR1 mRNA expression in PBMCs

BACKGROUND

Myocardial infarction (MI) and underlining atherosclerosis are the main causes of death worldwide. Phosphatase and actin regulator 1 (PHACTR1) variants have been associated with early onset MI, coronary artery disease and carotid dissection. PHACTR1 mRNA expression has been detected in tissues and cells related to atherosclerosis. Nonetheless, the true effect of PHACTR1 on vascular diseases is still unknown. Our aim was to examine the association of PHACTR1 intronic variants, rs9349379, rs2026458 and rs2876300, with MI and multi-vessel disease (MVD) and to assess their effect on PHACTR1 and EDN1 mRNA expression in PBMCs of patients six months after MI.

METHODS

The study enrolled 537 patients with the first MI and 310 controls. Gene expression was assessed in 74 patients six months after MI and 37 healthy controls. Rs9349379, rs2026458, rs2876300 and relative mRNA expressions were detected by TaqMan® technology.

RESULTS

The significant association between PHACTR1 variants and MI was not found, either individually or in haplotype. A higher frequency of rs2876300G-allele in MVD was rendered not significant after Bonferroni correction. PHACTR1 mRNA was significantly increased in PBMCs of patients six months after MI compared to controls (p = 0.02). Patients that carry ACG haplotype have increased PHACTR1 mRNA expression in PBMCs (p = 0.04). There was no effect of PHACTR1 variants on EDN1 mRNA expression.

CONCLUSION

Our findings suggest that PHACTR1 intronic variants may have a role in severity and progression of coronary atherosclerosis. Future research is needed to clarify the mechanism underlying the role of PHACTR1 in coronary atherosclerosis and MI.