Radiation Exposure to Patients Undergoing Percutaneous Coronary Interventions

PURPOSE: To determine predictors of patient radiation exposure due to percutaneous coronary interventions (PCI) and to compare our results with the "preliminary reference levels", recently proposed by the European DIMOND research cardiology group: i. e., 75 Gy.cm(2) for dose area kerma product (DAP), 17 min for fluoroscopy time (T(F)), and 1,300 for cinegraphic frames (F). MATERIAL AND METHODS: For 642 PCI-exclusive of the fraction for diagnostic catheterization to avoid statistical confounder effects-we measured total DAP, cinegraphic (DAP(C)) and fluoroscopic (DAP(F)) fractions, the number of cinegraphic frames and runs, and T(F). DAP(C)/F and DAP(F)/s were calculated to indicate the quality of focusing to the region of interest. RESULTS: The mean total patient DAP for elective one-, two-, and three-vessel PCI amounted to 6.7, 11.6, and 19.4 Gy.cm(2), for PCI of focal in-stent restenoses to 4.2 Gy.cm(2), and for excimer laser angioplasty of diffuse in-stent restenoses to 19.4 Gy.cm(2), respectively. Recanalization of chronic occlusions and PCI in acute myocardial infarction occasioned mean levels of 16.0 and 17.3 Gy.cm(2). Implantation of one and > or = two stents during one-vessel PCI significantly increased total mean DAP from a baseline level of 5.7 up to 7.1 and to 13.8 Gy.cm(2). DAP significantly varied according to the various PCI target regions and amounted to 4.0, 4.5, and 5.5 Gy.cm(2) for intermedius, diagonal, and left anterior descending arteries, to 4.9, 5.0, and 7.0 Gy.cm(2) for obtuse marginal, left posterolateral, and circumflex arteries, to 8.3, 9.1, and 9.5 Gy.cm(2) for proximal/mid right coronary segments, posterior descending, and right posterolateral arteries, and to 11.6 Gy.cm(2) for saphenous vein grafts, respectively. CONCLUSION: This study, carried through by consistent use of radiation-reducing techniques, enables a reliable scoring of patient radiation exposure according to complexity and target vessel of the intended PCI. Our 95th percentiles for elective PCI, for recanalizations of chronic occlusions, and for emergency PCI advise reference levels of 22, 32, and 42 Gy.cm(2) for DAP, of 16, 25, and 24 min for T(F), and of 400, 600, and 700 cinegraphic frames, respectively.     

Platelet Inhibition in Percutaneous Coronary Interventions

Abstract Mechanical disruption of atherosclerotic plaques at the time of percutaneous coronary intervention (PCI) is a potent stimulus for arterial thrombosis. Since platelets play a crucial role in the cascade of clot formation, platelet inhibition is an essential step for successful PCI. Aspirin remains the cornerstone of any antithrombotic regimen in the interventional setting. The addition of a thienopyridine is mandatory following stenting to prevent thrombosis of the device. Whenever possible, patients undergoing PCI should be pretreated with clopidogrel and the drug should be continued for up to 1 year. Glycoprotein IIb/IIIa antagonists should be administered in high-risk patients, such as those with acute coronary syndromes, diabetes, or complex coronary anatomy.     

Sex Differences in Percutaneous Coronary Interventions

Cardiovascular disease is the leading cause of mortality in women, and women have a higher cardiovascular mortality and morbidity associated with the treatment of cardiovascular disease compared to men. Percutaneous coronary intervention (PCI) is an important therapy for women with coronary artery disease particularly in acute coronary syndromes; however, only 33% of all PCIs are performed in women. The purpose of this review is to evaluate the evidence for PCI in women and demonstrate the unique aspects of therapy in regard to sex.     

Coronary Interventions in Congenital Heart Diseases: From Preterm to Young Adult Patients

Background

The small vessel size of infants and children makes interventional treatment of impaired coronary perfusion, such as stenoses, complete occlusions, and fistulae, demanding. Materials and techniques appropriate for this young age group have to demonstrate their ability to effectively treat these lesions.

Methods and Results

Between 2004 and 2011, 14 patients with an age of 9 days to 25 years (median 4.6 years) and a bodyweight of 1.7–65 kg (median 14 kg) underwent coronary intervention. In 3 cases, emergency revascularization of the left coronary artery (CA) was performed successfully, followed by stent implantation in 1 patient. Embolization of coronary arterial fistulae with coils and vascular plugs was effective in 10 patients. An antegrade, retrograde or combined approach to achieve the most distal device placement preserved all side branches. One infant with pulmonary atresia and an intact ventricular septum was prepared for biventricular repair by step‐by‐step closure of the right ventricular to the CA connections. No procedure‐related deaths occurred.

Conclusion

Congenital and post‐procedural coronary obstructive lesions can be considered for effective treatment with balloon dilation at any age as a salvage procedure. In coronaries impaired by external compression, stent implantation can restore perfusion, but long‐term results are missing. Interventional closure of coronary fistulae has shown improvement of coronary arterial perfusion. The latter techniques can be used to close right ventricular to CA connections in patients with pulmonary atresia to prepare for biventricular repair, but bail‐out strategies should be planned in all coronary interventions. (J Interven Cardiol 2013;26:287–294)

     

The Challenges of Today's Endovascular Interventions

Endovascular interventions are considered the main therapeutic treatment modality for many vascular occlusive diseases. New indications emerge as short- and long-term successes are reported. For new devices, there is a need to determine the superiority of one device or technique over another. Evaluation of these techniques is further complicated by the fact that the alternative therapeutic options (medical and surgical management) also are undergoing progressive refinement. While some of these results have been validated through state-of-the-art and expensive clinical trials, others are supported only by limited observational data due to lack of sufficient funding or restrictive regulations. New and modified devices allow cardiac interventionists to perform more complicated procedures and successfully treat more complex lesions in sicker and older patients. Still, there are many limitations such as diffuse lesions, poor distal run-off, or too small vessels. Another limitation is that the procedure is not affordable for the majority of patients. There are many unanswered questions regarding the techniques, strategies, and effectiveness of these new modalities of treatment. Only through additional studies and the passage of time will we know the answers to these questions.     

Bivalirudin in Percutaneous Coronary Interventions and Acute Coronary Syndromes: New Concepts, New Directions

Inhibition of thrombin and platelets during percutaneous coronary intervention (PCI), using a combination of unfractionated heparin and aspirin, is designed primarily to minimize the rare but devastating potential acute thrombotic complications of the procedure. Direct thrombin inhibitors, such as bivalirudin (formerly Hirulog, The Medicines Company, Cambridge, MA), offer specific theoretic advantages over unfractionated heparin as antithrombin therapy. This review focuses on the pharmacologic promise and the clinical performance of bivalirudin in PCI, and in the pharmacologic management of acute coronary syndromes. Clinical experience with bivalirudin in PCI preceded recent dramatic advances in mechanical interventional techniques and the emergence of novel potent platelet inhibitors. The role of bivalirudin and other direct thrombin inhibitors in the modern era of coronary intervention therefore requires further elucidation.     

Human Coronary Venous Anatomy: Implications for Interventions

The coronary venous system is a highly variable network of veins that drain the deoxygenated blood from the myocardium. The system is made up of the greater cardiac system, which carries the majority of the deoxygenated blood to the right atrium, and the smaller cardiac system, which drains the blood directly into the heart chambers. The coronary veins are currently being used for several biomedical applications, including but not limited to cardiac resynchronization therapy, ablation therapy, defibrillation, perfusion therapy, and annuloplasty. Knowledge of the details of the coronary venous anatomy is essential for optimal development and delivery of treatments using this vasculature. This article is part of a JCTR special issue on Cardiac Anatomy.     

Left Main Coronary Interventions: A Practical Guide

Coronary artery bypass surgery has been the accepted treatment for left main coronary artery disease for over 50 years. Balloon angioplasty was later used then abandoned because of deaths likely due to restenosis or thrombotic occlusion. However, rapid innovations in drug-eluting stent designs leading to more biocompatible thin strut platforms with optimal drug elution profiles and further advances in modern pharmacotherapy involving potent P2Y₁₂ inhibitors combined with utilization of intracoronary imaging and physiologic assessment for procedural planning and optimization have transformed percutaneous interventions into successful alternatives to coronary artery bypass graft surgery (CABG) in selected LM anatomic territories. Herein, we provide an evidence-based practical guide on how to approach and perform LM percutaneous interventions (PCI).