Treatment strategies in the left main coronary artery disease associated with acute coronary syndromes

Ostial lesion of the anterior descending coronary artery treated via Szabo technique supported by stent boost imaging: a case report

Background

Stenosis at the opening and bifurcation of the anterior descending branch and circumflex branch around the end of the left main trunk is difficult to repair. Accurate positioning of a stent is the key problem.

Case presentations

Here we report the case of a 61-year-old man who suffered from paroxysmal chest pain for 1 year, without history of diabetes or hypertension. The coronary computed tomography showed mixed plaques in the proximal part of the anterior descending artery, with stenosis severe at 80–90%. The emergency coronary angiography showed occlusion of the anterior descending artery. During percutaneous coronary intervention, a drug-eluting stent was implanted into the anterior descending artery using the Szabo technique, supported by stent boost (StentBoost) imaging to pinpoint the location of the lesion. The patient’s paroxysmal chest pain was relieved after the procedure.

Conclusion

We used StentBoost to verify the accuracy of stent placement and the Szabo technique to rectify long-term coronary stenosis, which achieved satisfactory results. Combining the Szabo technique with StentBoost imaging was helpful to accurately evaluate the area and locate the stent when treating this ostial lesion of the anterior descending coronary artery.

Bioresorbable Polymeric Scaffold in Cardiovascular Applications

Advances in material science and innovative medical technologies have allowed the development of less invasive interventional procedures for deploying implant devices, including scaffolds for cardiac tissue engineering. Biodegradable materials (e.g., resorbable polymers) are employed in devices that are only needed for a transient period. In the case of coronary stents, the device is only required for 6-8 months before positive remodelling takes place. Hence, biodegradable polymeric stents have been considered to promote this positive remodelling and eliminate the issue of permanent caging of the vessel. In tissue engineering, the role of the scaffold is to support favourable cell-scaffold interaction to stimulate formation of functional tissue. The ideal outcome is for the cells to produce their own extracellular matrix over time and eventually replace the implanted scaffold or tissue engineered construct. Synthetic biodegradable polymers are the favoured candidates as scaffolds, because their degradation rates can be manipulated over a broad time scale, and they may be functionalised easily. This review presents an overview of coronary heart disease, the limitations of current interventions and how biomaterials can be used to potentially circumvent these shortcomings in bioresorbable stents, vascular grafts and cardiac patches. The material specifications, type of polymers used, current progress and future challenges for each application will be discussed in this manuscript.

Acute, total occlusion of the left main stem: coronary intervention options, outcomes, and recommendations

Introduction

Acute, total occlusion of the unprotected left main stem (uLMo) in acute coronary syndrome (ACS) patients is a catastrophic event often accompanied by sudden cardiac death (SCD) and/or cardiogenic shock (CS) with high mortality rates and limited methods of successful treatment. Emergent, surgical and percutaneous revascularization has been reported before, yet comprehensive data remains scarce.

Aim

To examine emergency percutaneous coronary intervention (PCI) outcomes in ACS cases presenting with uLMo.

Material and methods

Data on 23 subjects undergoing primary PCI in uLMo cases were analyzed. The primary end-point was in-hospital death; secondary end-points were successful salvage of coronary anatomy and 90-day major cardiac adverse events (MACE).

Results

About 40% of LM occlusion cases presented following successful on-site cardio-pulmonary resuscitation (CPR). Of all patients arriving for treatment the occluded LM was successfully opened and stented in ~90% of cases. CS was present in > 85% of cases, and circulatory support in the form of intra-aortic balloon pump and/or extracorporeal membrane oxygenation systems was applied in every eligible case (~80%). The in-hospital death rate was 56%, mostly including individuals requiring prior CPR. At 6 months, additional MACE rates were low at 8.7%.

Conclusions

We found that uLMo ACS cases often present with preceding CPR and mostly in manifest CS. Coronary salvage is generally successful, yet uLMo even with optimal present day complex treatment yields quite high mortality rates. This is especially true for patients receiving prior CPR. In surviving patients, however, 6-month MACE rates are acceptable.

Human Plasma Metabolomics Implicates Modified 9-cis-Retinoic Acid in the Phenotype of Left Main Artery Lesions in Acute ST-Segment Elevated Myocardial Infarction

The detection of left main coronary artery disease (LMCAD) is crucial before ST-segment elevated myocardial infarction (STEMI) or sudden cardiac death. The aim of this study was to identify characteristic metabolite modifications in the LMCAD phenotype, using the metabolomics technique. Metabolic profiles were generated based on ultra-performance liquid chromatography and mass spectrometry, combined with multivariate statistical analysis. Plasma samples were collected prospectively from a propensity-score matched cohort including 44 STEMI patients (22 consecutive LMCAD and 22 non-LMCAD), and 22 healthy controls. A comprehensive metabolomics data analysis was performed with Metaboanalyst 3.0 version. The retinol metabolism pathway was shown to have the strongest discriminative power for the LMCAD phenotype. According to biomarker analysis through receiver-operating characteristic curves, 9-cis-retinoic acid (9cRA) dominated the first page of biomarkers, with area under the curve (AUC) value 0.888. Next highest were a biomarker panel consisting of 9cRA, dehydrophytosphingosine, 1H-Indole-3-carboxaldehyde, and another seven variants of lysophosphatidylcholines, exhibiting the highest AUC (0.933). These novel data propose that the retinol metabolism pathway was the strongest differential pathway for the LMCAD phenotype. 9cRA was the most critical biomarker of LMCAD, and a ten-metabolite plasma biomarker panel, in which 9cRA remained the weightiest, may help develop a potent predictive model for LMCAD in clinic.