Edward T.A. Fry

Reliable anticoagulation with enoxaparin in patients undergoing percutaneous coronary intervention: The pharmacokinetics of enoxaparin in PCI (PEPCI) study.

The objective of this study was to evaluate the pharmacokinetic response to intravenous (IV) enoxaparin given 8–12 hr after subcutaneous (SC) dosing in patients undergoing percutaneous coronary intervention (PCI). Fifty‐five patients received SC enoxaparin (1 mg/kg every 12 hr) followed by an IV bolus (0.3 mg/kg) 8–12 hr after the last SC dose, at the start of PCI or during catheterization. Anti‐Xa levels were within the target range in 98% of patients 2–8 hr after the last SC dose, in 96% of patients following the IV bolus, and in 91% of patients for a further 2 hr. Subcutaneous enoxaparin (1 mg/kg every 12 hr) provides sufficient anti‐Xa levels for PCI 2–8 hr after the last dose. An additional 0.3 mg/kg enoxaparin dose given IV 8–12 hr after the last SC dose reliably maintains anti‐Xa levels within the target for at least 2 additional hr. Catheter Cardiovasc Interv 2004;61:163–170.

Comparison of six-month outcome of coronary artery stenting in patients 75 years of age

We studied 1,238 patients receiving 1,880 coronary stents. In-hospital outcomes were divided by age into <65 years (n = 747, group 1), 65 to 75 years (n = 326, group 2), and >75 years (n = 165, group 3). Procedural success was 97.2%, 95.1%, and 98.8% in groups 1, 2, and 3, respectively (p = NS). There was 1 death (group 1). Myocardial infarction occurred in 1.2%, 2.8%, and 1.8%, bypass surgery occurred in 0.9%, 1.8%, and 1.2%, and repeat balloon angioplasty in 0.3%, 0.6%, and 0% of patients in groups 1, 2, and 3, respectively (p = NS for all comparisons). Vascular complications occurred in 2.8%, 4.9%, and 6.1% in groups 1, 2, and 3, respectively (p <0.05). Six-month follow-up of patients was divided by age: <65 years (n = 564, group 1); 65 to 75 years (n = 221, group 2); and >75 years (n = 122, group 3). Event-free survival was 94.5%, 90.5%, and 89.3% for groups 1, 2, and 3, respectively (p = NS). Death occurred in 0.4%, 0.5%, and 1.6%; myocardial infarction occurred in 1.2%, 2.3%, and 1.6%, and target vessel revascularization in 4.3%, 8.6%, and 7.4% for groups 1, 2, and 3, respectively (p = NS for all comparisons). Thus, coronary stenting produced favorable in-hospital and 6-month outcomes in all 3 age groups. Age itself should not preclude patients from undergoing coronary stenting.

Late coronary artery stenosis regression within the gianturco-roubin intracoronary stent

The late angiographic outcome of the Gianturco-Roubin intracoronary stent has not been well defined. To investigate serial changes within the stent, we studied 23 patients (15 men and 8 women, median age 63) who had late angiographic follow-up ( > 1 year) after undergoing Gianturco-Roubin stenting for angioplasty-associated acute or threatened native coronary artery closure. Coronary angiography before and after stenting, at 6-month follow-up, and at late return was analyzed with quantitative coronary angiography. The median time from stent deployment to late angiographic follow-up was 27 months. As expected, stenting significantly increased the median minimal lumen diameter (MLD) acutely from 1.0 to 2.46 mm. Median percent diameter stenosis decreased from 66% to 18%. Although at 6 months there was a significant loss of the acute gain (median MLD decreased from 2.46 to 1.9 mm), with a corresponding increase in percent stenosis from 18% to 31%, late angiography demonstrated lesion regression, median MLD increasing from 1.9 to 2.15 mm (p = 0.004), and percent stenosis decreasing from 31% to 21% (p = 0.0026). No patient had a significant decline in minimal lesion diameter, and 5 patients had a > 50% increase in MLD at late follow-up. Linear regression analysis of 6-month MLD and late lumen gain suggested that lesions with the greatest regression were those with the lowest lumen diameters at 6-month angiography. Late angiographic analysis demonstrated significant lesion regression within the Gianturco-Roubin stent, which was sometimes dramatic. In suggesting that coronary arteriography at 6 months may underestimate the late angiographic benefit of intracoronary stenting, these data have important clinical implications, and imply that patients with a stable clinical course and angiographic stent restenosis may often be followed rather than routinely redilated.

Coronary artery and saphenous vein graft remodeling: A review of histologic findings after various interventional procedures—part V

Catheter balloon angioplasty is a well accepted form of nonsurgical treatment of acutely and chronically obstructed coronary artery vessels. It is also the centerpiece for various new intervention techniques. Their morphologic effects on the site of obstruction has been termed “remodeling.” Part IV of this six‐part series focuses on morphologic correlates of coronary angiographic patterns of remodeling after balloon angioplasty and discusses effects of angioplasty on adjacent, nondilated vessels.

Atrial Fibrillation and Incident Myocardial Infarction

Atrial fibrillation (AF) occurs commonly, especially in the elderly, and is associated with increased mortality and a variety of serious conditions such as heart failure, stroke, and myocardial infarction (MI). In a recent article in JAMA Internal Medicine, Soliman et al1 analyzed data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study to evaluate whether AF was associated with increased risk for MI. After the researchers excluded patients with established coronary heart disease at baseline, 1631 patients with and 22 297 without AF were included in the analysis. The authors also examined subgroups of patients taking warfarin and aspirin at baseline, but data on serial anticoagulation use and international normalized ratio (INR) values were not available. The authors found that compared with patients without AF, those with AF were older, had worse kidney function, and were more likely to have diabetes and hypertension. During follow-up over 6.9 years (median of 4.5 years), there was a 2-fold increased risk of MI among patients with AF (hazard ratio, 1.96; 95% CI, 1.52-2.52).1 This finding remained significant after adjustment for known risk factors for coronary heart disease. In addition, in multivariableadjusted models, the association between AF and MI was stronger in black vs white individuals and in women vs men, although the association of AF with MI was not present in white men. In a separate multivariable model evaluating the relationship of warfarin and aspirin use with risk of MI associated with AF, warfarin was associated with a significantly reduced risk of MI, whereas there was no significant risk reduction associated with aspirin use. Furthermore, patients with AF and a CHADS2 score of greater than 1 had a higher risk of MI, compared with those with CHADS2 score of 0 or 1. These observations raise the questions of when and how warfarin may be beneficial to prevent an MI. A meta-analysis among patients who had coronary artery disease demonstrated a reduction in MI among those taking warfarin who had an INR of 2.8 to 4.8 but not among those with an INR less than 2.0.2 In the Warfarin Aspirin Reinfarction Study (WARIS II), warfarin alone (mean INR, 2.8) or with aspirin (mean INR, 2.2) reduced the reinfarction rate compared with JAMA INTERNAL MEDICINE

Quantitative and Qualitative Coronary Angiography

Although the technical quality of coronary angiographic images has dramatically improved, the method by which the great majority of clinical cardiac catheterization laboratories estimate coronary lesion severity has remained essentially unchanged. Most laboratories continue to rely on visual assessments of percent diameter stenosis, so called “eyeball” estimates, to define lesion severity. Unfortunately, these visual estimates are neither accurate nor precise [1–3]. Created to circumvent the weaknesses of “eyeball” measurements, quantitative coronary angiography (QCA) was developed to more reproducibly and accurately guage the magnitude of coronary obstructions [4–6]. Hand-held calipers were the first form of QCA. Subsequently, computer-assisted, quantitative angiographic systems were introduced.