In this preliminary series, sirolimus-eluting stent implantation appeared safe and effective for the treatment of dialysis patients with coronary artery disease. Dialysis patients are well known to be a high-risk population for cardiovascular morbidity and mortality, especially due to coronary atherosclerotic disease. However, the management of coronary disease in patients with end-stage renal failure is often problematic due to the presence of multiple co-morbidities and frequent limitations to drug prescription.¹ Moreover, these patients have been reported to be at a higher risk for short- and long-term complications after invasive treatment compared to non-dialysis patients.^2,3 The overall impact of invasive coronary treatment in dialysis patients is an ongoing debate.

The possible role of estrogen in coronary artery disease (CAD) has been extensively studied. Prospective randomized clinical trials have not substantiated a beneficial role for estrogen in CAD. The Heart and Estrogen/Progestin Study follow-up (HERS II) did not demonstrate a reduced risk of CAD after 6.8 years of hormone replacement therapy.¹ The Women’s Health Initiative (WHI) trial has concluded that overall health risks exceeded benefits with the use of hormone replacement therapy for a mean treatment period of 5.2 years.² There is no longer any support for systemic estrogens in CAD in clinical practice. The only remaining area of interest, therefore, is local delivery.
The vaso-protective effect of estrogen reaches beyond its effects on plasma lipids and atherosclerosis. Estrogen exerts a marked effect on the vascular endothelium, smooth muscle cells (SMC), and other components involved in tissue repair following arterial injury.

Aortic stenosis (AS) is prevalent in 2–7% of the population over 65 years of age.¹ Atherosclerotic coronary artery disease (CAD) coexists in 27–43% of patients with AS.² Management of CAD in patients with AS poses special problems since timing of surgery for AS depends on the development of symptoms, and treatment of CAD is often by concomitant coronary artery bypass graft (CABG) surgery. Surgical aortic valve replacement (AVR) is recommended in patients with moderate AS undergoing CABG, and in all patients with symptomatic severe AS.³ Whether PCI can be undertaken to fix coronary disease and defer AVR in these patients is an intriguing question. Ours is a retrospective study which evaluated the outcomes of PCI alone in surgically inoperable patients with moderate AS and compared them to patients who had AVR earlier and developed CAD over the following years.

Aortic stenosis (AS) and coronary artery disease (CAD) are both prevalent, with recent studies showing similar lesion histology, and also an association between traditional atherosclerotic risk factors and the development of AS.^1–3 The prevalence of calcific AS increases with age, affecting 2-3% of the population > 75 years of age.^2,4 Coexisting CAD (>= 70% diameter stenosis) is present in approximately 40% of patients with AS.5 Therefore, patients who require aortic valve replacement (AVR) for AS often undergo concomitant coronary artery bypass surgery (CABG).

The key treatment strategy for patients with acute ST-segment elevation myocardial infarction (MI) is rapid complete restoration of antegrade coronary flow.^1–6 Recognition of distal embolization of atherothrombotic debris in the microvasculature⁷ highlighted the significance of tissue level myocardial reperfusion⁸ in both fibrinolytic⁹ and catheter-based^10,11 therapies. Indeed, the “no-reflow” phenomenon occurs in >= 25% of patients with brisk antegrade flow following recanalization of anterior MI.¹² Indeed, the occurrence of “no-reflow” and distal embolization during direct percutaneous coronary intervention (PCI) portends a poorer outcome.¹³

Acute ST-segment elevation acute myocardial infarction (STEMI) is one of the main causes of morbidity, hospitalization and consequently increases healthcare costs. The primary goal of therapy in STEMI is to regain patency of the culprit vessel (TIMI 3 flow) and achieve myocardial reperfusion. Timely reperfusion of jeopardized myocardium represents the most effective way of restoring the balance between myocardial oxygen supply and demand. Primary percutaneous coronary intervention (PCI) was shown to be superior to thrombolytic therapy in terms of a higher patency rate (> 90%) of the infarct-related artery (IRA), and feasibility in patients with contraindications for thrombolysis and lower risk of serious bleeding.

The progressive nature of atherosclerotic renal artery stenosis is now well recognized.^1–8 Observational data suggests that untreated renal artery stenosis can lead to progressive hypertension, renal insufficiency, and increased mortality.^6,9–11 The incidence of progressive ischemic nephropathy resulting from atherosclerotic renal artery stenosis had been underestimated in the past. The U.S. Renal Data System annual report in 1999 revealed that up to 20% of new patients > 50 years old requiring hemodialysis have underlying renovascular disease.¹²

Intravascular contrast is a prerequisite for modern invasive cardiology. The contrast agents used for various procedures have become increasingly safe in recent years. Compared to ionic agents, the modern non-ionic contrast agents are fairly well tolerated, with a low incidence of serious adverse reactions.^1,2 Serious adverse events associated with contrast agent such as ventricular fibrillation do occur in a few patients. It is not known whether the fibrillation threshold is different between these agents in clinical practice. Patients continue to experience uncomfortable and distressing symptoms from the administration of contrast. Non-ionic contrast agents can be associated with late complications that may not be recognized as such.

EDITOR’S NOTE: This article by Diaz et al. contains extremely valuable information. The importance of assessing the “dynamic anatomy” of the popliteal artery (and other vessels) was only recently appreciated as a result of developments with endovascular therapy and the increasing use of fracture-prone intraluminal metallic stents. The findings described by the Argentinian group should prove useful to interventionists who are planning to perform a stenting procedure in a given patient. But even more so, they will likely have an impact on current R&D efforts and concepts surrounding stent technology for treatment of infra-inguinal disease — a very significant area in interventional medicine indeed! — Frank J. Criado, MD, Director, Center for Vascular Intervention, Chief, Division of Vascular Surgery, Union Memorial Hospital/MedStar Health, Baltimore, Maryland.

Case report. A 70-year-old woman with a history of smoking, hypertension and hyperlipidemia was referred for evaluation of exertional angina that had developed over the preceding 6 months. Thirteen years earlier, she had undergone balloon angioplasty of the mid-RCA following acute myocardial infarction. That procedure resulted in an acceptable final residual stenosis (estimated to be 25% by visual severity), but was notable for the creation of a longitudinal dissection at the angioplasty site. Current diagnostic cardiac catheterization documented the presence of a disrupted-looking significant stenosis of the proximal RCA, in addition to two parallel stenotic-appearing channels in the mid RCA (Figure 1). There were no other significant lesions in the coronary tree, and the left ventricular function was within normal limits.