ABSTRACT: Background. A 300 mg clopidogrel loading-dose (LD) is widely used as an adjunct antithrombotic treatment to reduce the risk of thrombotic events early after coronary stenting (CS). Antithrombotic drugs commonly used during percutaneous coronary interventions, such as heparin and platelet glycoprotein IIb/IIIa inhibitors, but not clopidogrel LD, are weight-adjusted, and few data are available on which is the most effective clopidogrel LD regimen. The aim of this study was to assess whether body mass index (BMI) influenced platelet response to clopidogrel LD in patients undergoing CS. Methods. Adenosine diphosphate (ADP)-induced platelet aggregation (PA) was assessed by light transmittance aggregometry in 48 patients on aspirin treatment undergoing CS receiving a 300 mg clopidogrel LD at intervention time. PA was assessed at baseline and up to 24 hours after intervention.

Finding the “right dose” of a medication for an individual patient remains an illusive challenge for the practicing clinician. As part of the drug approval process, drug developers use randomized controlled trials to determine the general safety and efficacy profiles of a drug using a standard dosing regimen. However, it is clear that pharmacokinetics and dynamics of a drug can vary markedly based on the patient’s age, body size and composition, renal and hepatic function, concomitant medications used and other factors. These issues are particularly relevant with anti-thrombotic or anti-coagulant therapy where the therapeutic window for efficacy and safety may be narrow. The current study by Angiolilio and colleagues addresses whether the “standard” dose of clopidogrel following percutaneous coronary intervention needs to be “super-sized” in larger patients.

ABSTRACT: Patients who develop acute myocardial infarction due to occlusion in a saphenous vein graft (SVG) constitute a revascularization challenge. Excimer laser angioplasty may have a potential advantage in the treatment of SVGs, since its 308 nanometer wavelength is avidly absorbed by both atherosclerotic plaque and thrombus. The data presented herein support the notion that excimer laser angioplasty is a technology that has a potential role in achieving adequate revascularization outcomes in this selected, high-risk patient population.

ABSTRACT: Objectives. To assess the impact of intraaortic balloon counterpulsation on coronary, renal and aortic blood flow in an animal heart failure model. Background. Heart failure exacerbations are still often treated with inotropic medications despite a lack of evidence demonstrating any benefit with these drugs. Intraaortic balloon counterpulsation may be considered in certain cases a bridge to recovery. Methods. Four juvenile pigs underwent pacemaker implantation to induce a rapid-pacing mediated dilated cardiomyopathy. After approximately 4 weeks of rapid pacing, the mean ejection fraction was reduced to 28.8 ± 9.5% with a mean systolic blood pressure of 64/44 mmHg. The pigs then underwent surgical placement of flow probes around the circumflex coronary artery, renal artery and infrarenal aorta. A Millar catheter was used to calculate Dp/Dt and a Swan-Ganz to calculate cardiac output. Data were recorded at baseline and after 10 minutes of balloon pumping.

Fischi et al.¹ sought to model the influence of intraaortic balloon counterpulsation (IABP) on coronary renal and aortic flow in subjects with congestive heart failure. The model involved examining responses in 5 juvenile pigs who had pacemaker implantation and rapid-pacing induced dilated cardiomyopathy. At 4 weeks, with the ejection fraction reduced to 28 ± 8% with a systemic pressure of 64/44 mmHg, the effect of IABP on blood flow across the circumflex coronary artery, the renal arteries and the infrarenal aorta was examined. High-fidelity pressure catheters were used to evaluate dp/dt and cardiac output. After 10 minutes of intraaortic balloon pumping, there appeared to be no significant hemodynamic or myocardial effects.

ABSTRACT: We evaluated the current short- and medium-term outcomes of complete revascularization, compared to “culprit” lesion percutaneous coronary intervention (PCI), in patients with multivessel coronary disease presenting with unstable angina. One hundred fifty-one patients with multivessel coronary disease presented to a tertiary cardiothoracic center with unstable angina/non-ST elevation myocardial infarction (UA/NSTEMI) between January 2000 and September 2001. In group A (n = 71), the intended strategy was complete revascularization by multivessel PCI. In group B (n = 80), culprit lesion PCI was intended despite the presence of other lesions amenable to PCI (B1) or due to confounding anatomical factors (B2).

ABSTRACT: Four years of follow-up renal function and survival data were obtained on 544 patients who underwent 714 successful renal artery stenosis (RAS) stent revascularizations. The mean serum creatinine (SCr) was unchanged at 4 years (1.6 ± 1.0 mg/dl versus 1.6 ± 0.9 mg/dl). The 2-year paired comparison analysis revealed no change in the reciprocal of the SCr (1/SCr), when compared with baseline or 1-year follow-up values. Simple linear regression analysis revealed flat post-procedure trend line slopes within all patient subsets, which implied renal functional stabilization.

Renal artery stenosis is a serious disease that is associated with high rates of cardiovascular morbidity and mortality. It has been believed that severe renal artery stenosis contributes to hypertension and renal dysfunction and that these are the primary mechanisms behind the adverse sequelae of renal artery stenosis. In addition, the presence of renal artery stenosis serves as a marker for significant atherosclerosis elsewhere. While this has been the traditional view of renal artery stenosis, there is evidence that embolization may also play an important role.

Case Report. The patient was a 76-year-old male with the cardiovascular risk factors of hypertension and hyperlipidemia. His cardiovascular history began in April 2000, with a myocardial infraction (MI) of the anteroseptal wall; although, he was managed conservatively. Four months later, the patient presented with an acute reinfarction of the anteroseptal wall, and was experiencing post-MI angina. Diagnostic cardiac catheterization revealed triple vessel disease. The patient underwent double coronary artery bypass graft (CABG) surgery. A saphenous vein graft (SVG) was inserted on the left anterior descending artery (LAD) and another SVG was inserted on an obtuse marginal (OM) branch; the right coronary artery was not considered suitable for revascularization. The patient remained asymptomatic until July 2001.

ABSTRACT: We encountered a case of intractable radial artery graft spasm after stent implantation which was partially responsive to nominal nitroglycerin therapy. We report this case with intravascular ultrasound imaging at the radial artery spasm site.