Gloria Melzi

Incidence and Predictors of Drug-Eluting Stent Thrombosis During and After Discontinuation of Thienopyridine Treatment

Background— The need for prolonged aspirin and thienopyridine therapy and the risk of stent thrombosis (ST) remain as drawbacks associated with drug-eluting stents. Methods and Results— A prospective observational cohort study was conducted between June 2002 and January 2004 on 3021 patients consecutively and successfully treated in 5389 lesions with drug-eluting stents. Detailed patient information was collected on antiplatelet therapy. We analyzed the incidence of ST throughout the 18-month follow-up period and its relationship with thienopyridine therapy. ST occurred in 58 patients (1.9%) at 18 months. Forty-two patients (1.4%) experienced the event within 6 months of stent implantation. Acute myocardial infarction (fatal or nonfatal) occurred in 46 patients (79%) and death in 23 patients (39%) with ST. The median interval from discontinuation of thienopyridine therapy to ST was 13.5 days (interquartile range 5.2 to 25.7 days) for the first 6 months and 90 days (interquartile range 30 to 365 days) between 6 and 18 months. On multivariable analysis, the strongest predictor for ST within 6 months of stenting was discontinuation of thienopyridine therapy (hazard ratio, 13.74; 95% CI, 4.04 to 46.68; P<0.001). Thienopyridine discontinuation after 6 months did not predict the occurrence of ST (hazard ratio, 0.94; 95% CI, 0.30 to 2.98; P=0.92). Conclusions— Discontinuation of thienopyridine therapy was the major determinant of ST within the first 6 months, but insufficient information is available to determine whether there is benefit in continuing a thienopyridine beyond 6 months.

Percutaneous Treatment With Drug-Eluting Stent Implantation Versus Bypass Surgery for Unprotected Left Main Stenosis A Single-Center Experience

Background— Improvements in results with percutaneous coronary intervention (PCI) with drug-eluting stents (DES) may extend their use in patients with left main coronary artery (LMCA) stenosis. Methods and Results— Two hundred forty-nine patients with LMCA stenosis were treated with PCI and DES implantation (n=107) or coronary artery bypass grafting (CABG) (n=142), in a single center, between March 2002 and July 2004. A propensity analysis was performed to adjust for baseline differences between the two cohorts. At 1 year, there was no statistical difference in the occurrence of death in PCI versus CABG both for the unadjusted (OR=0.291; 95% CI=0.054 to 1.085; P=0.0710) and adjusted analyses (OR=0.331; 95% CI=0.055 to 1.404; P=0.1673). PCI was correlated to a lower occurrence of the composite end points of death and myocardial infarction (unadjusted OR=0.235; 95% CI=0.048 to 0.580; P=0.0002; adjusted OR=0.260; 95% CI=0.078 to 0.597; P=0.0005) and death, myocardial infarction, and cerebrovascular events (unadjusted OR=0.300; 95% CI=0.102 to 0.617; P=0.0004; adjusted OR=0.385; 95% CI=0.180 to 0.819; P=0.01). No difference was detected in the occurrence of major adverse cardiac and cerebrovascular event at the unadjusted (OR=0.675; 95% CI=0.371 to 1.189; P=0.1891) and adjusted analyses (OR=0.568; 95% CI=0.229 to 1.344; P=0.2266). Conclusions— At 1 year, in this single-center, retrospective experience, there was no difference in the degree of protection against death, stroke, myocardial infarction, and revascularization between PCI with DES and CABG for LMCA disease.

Gadolinium-based contrast agents and nephrotoxicity in patients undergoing coronary artery procedures

Objective: We tested whether gadolinium‐based contrast agent is less nephrotoxic than iodinated‐contrast media. Background: Iodinated contrast agents are nephrotoxic. Some data suggest that gadolinium‐based contrast agent may be less nephrotoxic than iodinated‐contrast media. Methods: Twenty‐five consecutive patients with chronic renal insufficiency (creatinine concentration ≥2.0 mg/dl and/or clearance ≤40 ml/min), referred to our institution for coronary procedures, were assigned to receive gadolinium‐based contrast agents, a solution of gadolinium chelates diluted 3:1 by iso‐osmolality contrast media (Gadolinium‐based group). A control group of 32 patients with comparable clinical characteristics and treated with iodinated iso‐osmolality contrast agent alone (Iodinated‐based group) was selected from our database and compared with the Gadolinium‐based group. In all cases, prophylactic administration of 0.45% saline intravenously and NAC (1200 mg orally twice daily) was used. Results: Baseline creatinine levels and creatinine clearance were similar in the 2 groups (Gadolinium‐based group = 2.30 [IQR: 2.01–2.68] mg/dl and 33 ± 13 ml/min; Iodinated‐based group = 2.24 [IQR: 2.05–2.65] mg/dl and 30 ± 10 ml/min; P >0.05 for all). Increase of at least 0.5 mg/dl of the creatinine concentration 48 hr after the procedure occurred in 7/25 (28%) patients in the Gadolinium‐based group and in 2/32 (6.5%) patients in the Iodinated‐based group (P = 0.034; OR = 4.48; 95% CI = 1.01–19.17). Renal failure requiring temporary dialysis occurred in 2 (8%) patients in the Gadolinium‐based group and in none in the Iodinated‐based group (P = 0.19). Conclusions: The strategy of gadolinium‐based contrast agent administration does not seem to reduce the rate of CAN, as compared to the iodinated iso‐osmolality contrast agent in patients with chronic renal insufficiency.© 2006 Wiley‐Liss, Inc.

A novel approach to chronic total occlusions: the crosser system.

Objectives: To evaluate safety and efficacy of the CROSSER CTO Recanalization System (CROSSER). Background: The CROSSER, a novel device dedicated to recanalization of chronic total occlusions (CTO), relies on a monorail catheter delivering vibrational energy to facilitate the crossing of occluded coronary arteries. Methods: We included de novo or restenotic occlusions in native coronary arteries with typically unfavorable characteristics and a prior failed guidewire attempt either performed in a previous procedure or just before the usage of the CROSSER. The end points analyzed were technical success (ability to cross or facilitate a guidewire crossing into the true lumen), angiographic success (<20% residual stenosis and TIMI flow grade 3), and clinical success (angiographic success and freedom from major adverse cardiac events at 30 days). Results: Twenty‐eight patients (30 lesions) were included. The morphology was blunt in 83.3% and the length of the occlusion was >20 mm in 76.6%. The median age of the CTO was 9 months (range 3–60 months). Technical success was obtained in 19 (63%) occlusions and angiographic success in 16 (53%): 26.3% in lesions with prior procedural failure and 73.7% when CROSSER was attempted after initial guidewire failure. Complications were: one guidewire perforation without consequences and one peri‐procedural myocardial infarction (MI). No events occurred within 30‐day follow‐up after discharge. Conclusions: In our experience, the CROSSER System is safe and increases the success of opening CTO refractory to guidewires. This novel device may represent an useful adjunct to the armamentarium of the interventional cardiologist.

Comparison of changes in respiratory function and exercise oxygen uptake with losartan versus enalapril in congestive heart failure secondary to ischemic or idiopathic dilated cardiomyopathy.

In congestive heart failure (CHF), some of the effects of angiotensin-converting enzyme (ACE) inhibitors, such as an increase in exercise oxygen uptake (VO2), are mediated through prostaglandins. Angiotensin (AT1) receptor blockers apparently do not share potentiation of this biosystem. We tested whether losartan improves exercise VO2 in CHF and if the effect is the same as for enalapril. Sixteen men with CHF and 8 volunteers, all nonsmokers and not taking ACE, AT1 receptor, or cyclooxygenase inhibitors, were randomized to receive placebo, enalapril (10 mg 2 times daily), losartan (50 mg/day), each of these 2 drugs plus aspirin (325 mg/day), aspirin, or the same preparations in a reverse order, each for 3 weeks, with a 3-week washout period between treatments. Pulmonary function and VO2 were assessed at the end of each treatment. In CHF, losartan and enalapril caused a similar improvement of VO2 and exercise tolerance, which was absent in controls and was counteracted by aspirin (prostaglandin inhibition) when obtained with enalapril and not with losartan. While on enalapril, we also detected an increase in the diffusing lung capacity for carbon monoxide, which correlated with changes in VO2 and was antagonized by aspirin, suggesting the possibility that a prostaglandin-mediated functional improvement of the alveolar capillary membrane contributes to the rise in VO2. Thus, losartan is as effective as enalapril for exercise VO2 and exercise tolerance, but the mechanism seems to be dissociated from a prostaglandin biosystem activation. Losartan may represent an advancement in CHF because its efficacy on VO2 is similar to that of enalapril, but is not antagonized by aspirin.

Angiotensin-converting enzyme inhibition facilitates alveolar-capillary gas transfer and improves ventilation-perfusion coupling in patients with left ventricular dysfunction

The backward effects of left ventricular dysfunction include alterations in alveolar‐capillary gas transfer and ventilation‐perfusion coupling. Because the angiotensin‐converting enzyme (ACE) is highly concentrated in the vascular endothelium of the lungs, we examined whether ACE inhibitors may influence the pulmonary function in patients with congestive heart failure.

Persistent redundant Eustachian valve interfering with Amplatzer PFO occluder placement: Anatomico-clinical and technical implications

A 28‐year‐old man with patent foramen ovale and a prominent Eustachian valve with a history of transient ischemic attack underwent transcatheter closure using Amplatzer patent foramen ovale occluder. During deployment, some of the prominent valve tissue was entrapped on the delivery cable and a piece of the valve was extracted unintentionally. Anatomico‐clinical and technical implications are discussed. Cathet Cardiovasc Intervent 2002;55:521–524.

Letter by Brocco et al Regarding Article, “Percutaneous Treatment With Drug-Eluting Stent Implantation Versus Bypass Surgery for Unprotected Left Main Stenosis: A Single-Center Experience”

In the letter by Brocco et al, the authors focused on the correspondence between clinical relevance and statistical significance. The decision to emphasize study results as clinically relevant but not statistically significance is quite controversial in relatively small retrospective studies with exploratory purposes such as our study.1 In our opinion, a pragmatic “win criterion” for these kinds of studies would be the simultaneous achievement of both clinical and statistical significance. We do not believe that not mentioning as clinically relevant a non–statistically significant difference can substantially bias the readers’ conclusions any more than emphasizing as noteworthy a difference that is potentially coincidence. In the letter by Pocar et al, different issues are raised. The authors pointed out the problem of the incomplete revascularization (IR), which is frequently evoked as a limitation of percutaneous transluminal coronary angioplasty as compared with bypass …