Percutaneous coronary intervention (PCI) of a chronic total occlusion (CTO) remains one of the more difficult technical challenges for interventional cardiologists, despite the progress made in the field of PCI in the past decade. CTOs (found in one-third of patients with significant coronary disease) represent only about 10% of all PCI cases.¹ Failure to revascularize a CTO often leaves the patient with either the more invasive option of coronary artery bypass graft surgery (CABG), or continuing medical therapy, which may or may not control anginal symptoms. In addition, leaving a vessel occluded may also have detrimental consequences on long-term survival.^2,3 The success rate of PCI for CTOs varies widely (range = 40–80%), depending on the location and characteristics of the CTO as well as the operator’s experience.^4,5 The main technical reason for an unsuccessful PCI for CTOs is the failure to cross the occlusion with the guidewire.

Although coronary artery bypass grafting (CABG) is the preferred treatment for disease in an unprotected left main coronary artery or left main equivalent, patients with serious comorbid conditions may be unsuitable for surgical intervention. Percutaneous coronary intervention (PCI) offers a nonsurgical approach for selected patients, but its morbidity and mortality rates can be unacceptably high in the presence of comorbidities, particularly poor left ventricular function.^1–4 During high-risk PCI, physicians have used various methods of circulatory support, including intra-aortic balloon pump (IABP) counterpulsation^5–7 and extracorporeal membrane oxygenation.^8,9 We report our initial experience with the TandemHeart Percutaneous Ventricular Assist Device (pVAD) (CardiacAssist, Inc., Pittsburgh, Pennsylvania) (Figure 1) for supportive therapy during high-risk PCI.

Individual protocols for mobilization after diagnostic cardiac catheterization differ widely between units. Prolonged bed rest increases patient discomfort, limits total numbers of procedures and increases healthcare costs. The current trend is to recommend earlier mobilization. This is beneficial in terms of patient comfort, provided there is no increase in vascular complications.
We conducted a prospective study of early ambulation following diagnostic cardiac catheterization. Our aim was to assess the safety and efficacy of a 90-minute bed rest protocol for patients having undergone elective 6 Fr femoral access coronary angiography.

Materials and Methods

In this issue of the Journal, Biswajit Kar, et al. report their initial experience using the TandemHeart Percutaneous Ventricular Assist Device (CardiacAssist, Inc., Pittsburgh, Pennsylvania) in patients who were undergoing a high-risk percutaneous coronary intervention (PCI). The authors chose patients who were at risk for hemodynamic collapse during the PCI. These patients had an unprotected left main stenosis or the equivalent, and were not considered to be candidates for cardiac surgery because of their multiple medical comorbidities.

There has been an impressive decrease in the incidence of vascular complications following cardiac catheterization in recent years;¹ however, excess bleeding from the access site, hematoma, arteriovenous fistula and arterial pseudoaneurysm formation continue to lengthen patients’ hospital stay and affect morbidity. After diagnostic left heart catheterization from the femoral artery, hemostasis has traditionally been achieved through manual compression with the fingertips over the arterial pulse. Many operators act on anecdotal evidence when determining the duration of patient bed rest following arterial sheath removal. Some support the notion that 3 minutes of manual pressure per catheter French size is sufficient for hemostasis while 1 hour of bed rest per French size is necessary to maintain hemostasis; however, statements such as these are largely untested.

While an increasing proportion of the grafts used during coronary artery bypass (CABG) procedures are arterial, the majority of grafts implanted at most centers have been and continue to be saphenous vein grafts. On long-term follow up, up to 50% of such vein grafts may be occluded.^1,2 Consequently, a significant number of patients with previous CABG eventually require percutaneous coronary intervention (PCI) of diseased vein grafts. Compared to native coronary arteries, saphenous vein grafts (SVG) have a higher plaque burden and are more likely to have lesions that are diffuse, concentric and friable.³ These factors contribute to the significantly worse early and long-term outcomes seen after SVG PCI.^4–7

Recent studies have shown that the use of drug-eluting stents (DES) to deliver antiproliferative agents directly to the vessel wall dramatically reduces the rate of restenosis. However, differences among stent designs, drug delivery vehicles, and choices of pharmacologic agents can significantly affect the safety and efficacy of each device. Thus, focused study on the various constituents of delivery platforms, including the stent backbone, materials used as drug delivery vehicles and the physicochemical properties of the pharmacotherapeutic agents themselves is indicated.^1,2 In addition, several clinical trials compared the Taxus^® (Boston Scientific Corp., Natick, Massachusetts) and Cypher™ (Cordis Corp., Miami, Florida) stents, showing a difference in neointimal proliferation between these two devices, and suggesting that the drug delivery platform may account for this difference.^3–8

Obesity affects over 20% of the U.S. population and most countries in the developing world.^1,2 It is an independent risk factor for premature coronary artery disease and is associated with an increase in cardiac morbidity and mortality, similar to the consequences of long-term cigarette smoking, diabetes, hypertension and hyperlipidemia.^3,4

The benefits of transradial access for percutaneous coronary intervention have been clearly documented in the past several years.^1–10 However, postprocedure radial artery occlusion is a potential complication, and adequate anticoagulation is an absolute prerequisite, even for diagnostic procedures.^11–13
As a result of its proven efficacy in several recent clinical trials, the direct thrombin inhibitor bivalirudin (Angiomax®, The Medicines Company, Parsippany, New Jersey) is now increasingly utilized as the anticoagulant of choice for coronary interventions.^14–19 However, it is currently not packaged for diagnostic procedures. Thus, patients undergoing ad hoc transradial interventions need unfractionated heparin (UFH) during the diagnostic catheterization, but it is unclear how the transition to bivalirudin should be undertaken if a subsequent intervention were performed.

Patients with peripheral artery disease (PAD) undergoing percutaneous peripheral interventions (PPI) are at high risk for thrombotic complications. Though not approved for use in PPI, heparin is the most commonly used anticoagulant, despite its well-known pharmacological and clinical limitations. Data in the literature regarding heparin use in PPI are limited; however, in-hospital complication rates have been reported as ranging from 3.5% to 32.7%.¹