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Warren K Laskey

Publications and source records attributed to Warren K Laskey.

At least 37 records · Page 2Linked to original sources
PubMed2004

Clinical progression of incidental, asymptomatic lesions discovered during culprit vessel coronary intervention.

BACKGROUND: With the reduction in restenosis rates by drug-eluting stents, there is new controversy concerning the optimal management of incidental, nontarget lesions identified during percutaneous coronary intervention (PCI). Such lesions have been treated conservatively because of risk of restenosis but now are being considered for PCI to prevent plaque instability. However, the impact of incidental stenoses on future cardiac events remains unknown. METHODS AND RESULTS: We performed a retrospective cohort study to determine the rate and features of clinical plaque progression using the National Heart, Lung, and Blood Institute Dynamic Registry of consecutive patients undergoing PCI at multiple centers in 1997 to 1998 and 1999. Of 3747 PCI patients, 216 (5.8%) required additional nontarget lesion PCI for clinical plaque progression at 1 year. Fifty-nine percent presented with new unstable angina, and 9.3% presented with nonfatal myocardial infarction. Patients with multivessel coronary artery disease during original PCI were more likely to require nontarget lesion PCI during follow-up (adjusted odds ratio, 1.72 [95% CI, 1.18 to 2.52] for 2 vessels; adjusted odds ratio, 3.37 [95% CI, 2.32 to 4.89] for 3 vessels). Angiographic review showed that the majority (86.9%) of lesions requiring subsequent PCI were < or =60% in severity during original PCI, with the mean lesion stenosis 41.8+/-20.8% at the time of the initial PCI and 83.9+/-13.9% during the recurrent event. CONCLUSIONS: Approximately 6% of PCI patients will have clinical plaque progression requiring nontarget lesion PCI by 1 year. Greater coronary artery disease burden confers a significantly higher risk for clinical plaque progression.

Angioplasty, Balloon, Coronary↗
PubMed2004

Outcomes in patients with diabetes mellitus undergoing percutaneous coronary intervention in the current era: a report from the Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) trial.

BACKGROUND: Diabetes portends an adverse prognosis in patients undergoing percutaneous coronary intervention (PCI). Whether improvements in current clinical practice (stents, IIb/IIIa antagonists) have resulted in substantial improvement of these outcomes remains an issue. The aim of this study was to determine the influence of diabetes on 9-month outcomes of patients undergoing PCI in the current era. METHODS AND RESULTS: The 11 482 patients enrolled in the Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) Trial were stratified according to the presence (n=2694) or absence (n=8798) of diabetes. Diabetic patients were older; were more likely to be female; had a higher proportion of congestive failure, hypertension, prior CABG, and unstable angina; and had higher body mass index and lower ejection fraction than nondiabetic patients (P<0.01 for all comparisons). The degree of multivessel disease was similar between the two groups. American College of Cardiology/American Heart Association type C lesions were more common in diabetic patients (17% versus 15%, P<0.01). Angiographic and procedural success rates and in-hospital events were similar between the two groups. The primary end point of death, myocardial infarction, or target vessel revascularization (TVR) was analyzed as time-to-first event within 9 months of the index PCI. After adjusting for certain baseline characteristics, diabetes was independently associated with death at 9 months (relative risk [RR], 1.87; 95% CI, 1.31 to 2.68, P<0.01) and with an increased likelihood of TVR (RR, 1.27; 95% CI, 1.14 to 1.42, P<0.01), as well as the composite end point of death/myocardial infarction/TVR (RR, 1.26; 95% CI, 1.13 to 1.40, P<0.01). CONCLUSIONS: Despite advances in interventional techniques, diabetes remains a significant independent predictor of adverse events in the intermediate term after PCI.

Coronary Angiography↗
PubMed2004

Ethical issues for invasive cardiologists: Society for cardiovascular angiography and interventions.

In view of the major impact of medical economic forces, rapidly changing technology, and other pressures on invasive cardiologists, the Society for Cardiovascular Angiography and Interventions determined that a statement of the ethical issues confronting the modern invasive cardiologist was needed. The various conflicts presented to the cardiologist in his or her roles as practicing clinician, administrator of the catheterization laboratory, educator, or clinical researcher were reviewed. In all instances, the major concern was determined to be the welfare of the patient no matter how forceful the pressures from various outside force or concerns for personal advancement might be.

Biomedical Research↗
PubMed2004

Flat-panel detectors in the cardiac catheterization laboratory: revolution or evolution-what are the issues?

Continuous developments in digital imaging technology have contributed to the vital role held today by digital X-ray imaging in the cardiac catheterization laboratory. Foremost among these developments is the replacement of cine film with digital data equivalents as the procedure record. Other improvements include software innovations and processing algorithms, along with new types of hardware capable of delivering required functionality more rapidly. A significant recent development is that of the flat-panel X-ray detector as a replacement for the image intensifier, which has served the needs of the cardiac catheterization laboratory for nearly 5 decades. Clinical users must evaluate the respective technologies and determine whether one or the other meets the needs of their own laboratories. In this review, the two competing detector technologies are reviewed and a summary of general advantages and disadvantages of each is provided. A qualitative description is provided of parameters that can be used to assess quantitatively the performance of detectors and imaging systems. Using such objective measurements, together with standard techniques for evaluating imaging systems, angiographers and managers can better arrive at informed decisions for their own situation.

Cardiac Catheterization↗
PubMed2004

SCAI statement on ad hoc versus the separate performance of diagnostic cardiac catheterization and coronary intervention.

Coronary intervention may be combined with diagnostic cardiac catheterization or performed separately. In the early years of angioplasty, performing these procedures separately was standard practice. Gradually, ad hoc intervention (performing diagnostic angiography and coronary intervention within the same session) has become more common, largely because of its convenience for patients and efficiency for physicians. However, the safety and potential cost savings of this approach remain uncertain. Criteria for the appropriate use of ad hoc intervention have not been established. Ad hoc intervention is reasonable for many, but not appropriate for all patients and should not be considered standard therapy. This document updates an earlier review of this topic and provides suggestions for the use of ad hoc intervention as a routine strategy.

Angioplasty, Balloon, Coronary↗
PubMed2003

Ethnic differences in the presentation, treatment strategy, and outcomes of percutaneous coronary intervention (a report from the National Heart, Lung, and Blood Institute Dynamic Registry).

Information about the impact of race/ethnicity on adverse outcomes after percutaneous coronary intervention (PCI) in the modern era is limited. Using consecutive patients from the National Heart, Lung, and Blood Institute Dynamic Registry, this study investigated differences in clinical presentation, treatment strategy, and acute and long-term outcomes in 3,669 white, 446 black, 301 Hispanic, and 201 Asian patients who underwent PCI. All comparisons were made to whites. Blacks were more likely than whites to be younger, women, and to present with a higher prevalence of cardiovascular risk factors (hypertension, diabetes, and smoking). Hispanics tended to be younger, hypertensive, diabetic, and to be undergoing their first cardiovascular procedure. Asians were, on average, younger, men, and presented more often with hypertension and diabetes than whites. Although the rate of stent implantation was significantly lower in blacks compared with whites (63% vs 74%, p <0.001), angiographic and procedural success rates were high (> or =95%) and did not differ by race/ethnicity. In-hospital mortality (0.2% vs 1.7%, p <0.05) and death/myocardial infarction (MI)/coronary artery bypass grafting (CABG) (3.1% vs 5.5%, p <0.05) were lower in blacks. All other in-hospital complications were similar to whites. At 1 year, there were no statistical differences in cumulative adverse event rates by ethnicity; however by 2 years there was a modestly higher mortality rate (adjusted RR 1.87; 95% confidence interval 1.15 to 3.04) and adverse event rate (death/MI, death/MI/CABG) among black patients. Thus, although differences in patient demographics, clinical presentation, angiographic characteristics and treatment strategies did not impact the incidence of acute and 1-year adverse outcomes of non-whites, there appears to be a significant reduction in event-free survival among blacks by 2 years.

Age Distribution↗
PubMed2003

Vascular brachytherapy using a beta emitter source in diabetic patients with in-stent restenosis: angiographic and clinical outcomes.

PURPOSE: The management of diabetic patients with restenosis after percutaneous coronary intervention remains a significant challenge. Diabetic patients remain at significant risk of restenosis despite stent implantation. This retrospective analysis was performed to determine the extent to which vascular brachytherapy improves late clinical and angiographic outcomes in diabetic patients compared to conventional therapy and compared to patients' nondiabetic counterparts. METHODS: Pooled data from two studies (START [Stents and Radiation Trial] and START-40 trials) of patients (204 diabetic, 477 nondiabetic) receiving vascular brachytherapy (VBT) with a (90)Sr/(90)Y source after conventional percutaneous coronary intervention for in-stent restenosis comprise the study population. The radiation delivery system used in both studies was the Beta-Cath system. The prescribed dose at 2 mm from the centerline of the source axis was 18.4 Gy or 23 Gy, depending on vessel diameter. The reference vessel diameter, minimal lumen diameter, and percent diameter stenosis were measured before the intervention, at the conclusion of the procedure, and at the 8-month follow-up examination. The Breslow-Day test was used to formally assess the similarity of treatment effect between diabetic and nondiabetic patients. RESULTS: Target lesion and target vessel revascularization rates and angiographic restenosis rates in diabetic and nondiabetic patients treated with beta radiation or placebo were analyzed. Diabetic patients were more likely to have longer and more complex coronary lesions. In-hospital outcomes in diabetic and nondiabetic patients were similar, irrespective of treatment status. At 8 months, patients treated with beta radiation exhibited less target lesion revascularization (diabetic: 10.9% vs. 22.7%, p = 0.02; nondiabetic: 12.8% vs. 22.3%, p = 0.007) and less target vessel revascularization (diabetic: 14.7% vs. 25.3%, p = 0.06; nondiabetic: 16.6% vs. 23.6%, p = 0.06) compared to placebo. In-stent binary angiographic restenosis was lower in irradiated patients (diabetic: 19.4% vs. 37.3% for placebo, p = 0.01; nondiabetic: 12.9% vs. 43% for placebo, p < 0.001). However, restenosis beyond the stent site reduced the impact of VBT, regardless of diabetic status. The magnitude of the treatment effect for target lesion and target vessel revascularization rates was similar between diabetic and nondiabetic patients. CONCLUSIONS: Previously published institutional experiences have suggested that diabetic patients benefit from the use of VBT in the management of in-stent restenosis. This analysis now provides direct evidence to support the role of beta radiation VBT in this patient population. Diabetic patients undergoing this therapy are just as likely to benefit from it as their nondiabetic counterparts.

Beta Particles↗
PubMed2003

Frequency and clinical significance of ischemic preconditioning during percutaneous coronary intervention.

OBJECTIVES: We sought to examine the short- and long-term clinical consequences of ischemic preconditioning (IP) during percutaneous coronary intervention (PCI). BACKGROUND: Ischemic preconditioning has been demonstrated in animal models to significantly diminish the extent of myocardial necrosis consequent to coronary occlusion. Surrogate markers of ischemic injury (ST segment shift, lactate release, creatine kinase release) in humans have been shown to be similarly diminished with IP elicited during PCI. There are no studies of the frequency of inducibility of IP during PCI, nor are there longer-term data on the clinical relevance of IP. METHODS: A total of 382 patients underwent elective PCI employing a previously validated protocol to elicit IP. Procedural, in-hospital, and one-year outcomes were recorded. RESULTS: Ischemic preconditioning was elicited in 80% of patients and was associated with a significant reduction in the likelihood of in-hospital adverse cardiac events (IP group, 12.1%; non-IP group, 44.1%; p < 0.0001). Women and diabetic patients were less likely to exhibit IP. By one year, patients failing to manifest IP were at significantly greater risk of post-discharge death or non-fatal myocardial infarction (MI) (non-IP group, 25.9%; IP group, 11.1%; p < 0.002). Failure to manifest IP was significantly and independently associated with an increased risk of death or non-fatal MI by one year. CONCLUSIONS: Clinically relevant short- and long-term cardioprotection can be found in association with IP during PCI. In-hospital adverse ischemic events are significantly diminished in patients with IP, as are the risks of death or non-fatal MI at one year. Failure to elicit IP during PCI serves as an independent marker of increased risk of future ischemic events.

Angioplasty, Balloon, Coronary↗
PubMed2003

Bleeding risk of platelet glycoprotein IIb/IIIa receptor antagonists in broad-based practice (results from the Society for Cardiac Angiography and Interventions Registry).

Randomized trials of platelet glycoprotein (GP) IIb/IIIa receptor inhibitors in patients who have undergone percutaneous coronary intervention (PCI) have shown a modest increase in bleeding risk associated with GP IIb/IIIa inhibitor use. Because clinical trials often enroll highly selected patient populations and are performed in high-volume experienced centers, these results may not apply to a nonclinical trial population, thus altering the risk-benefit ratio of the drugs. Given the widespread use of these agents, we sought to determine bleeding risks in a broad-based population of patients who underwent PCI. We performed a retrospective cohort study of GP IIb/IIIa inhibitors and bleeding in 18,821 procedures from June 1, 1996 to December 31, 1998 using the Society for Cardiac Angiography and Interventions Registry. The primary outcome was bleeding events, defined as clinically significant hematoma formation or hemorrhage. Bleeding risk was 1.9% in the 2,525 patients who received GP IIb/IIIa inhibitors compared with 1.0% in the 16,296 who did not (unadjusted odds ratio [OR] 1.87, 95% confidence interval [CI] 1.35 to 2.59, p <0.001). After adjustment for multiple clinical and procedural variables, the effect was attenuated, with at most a twofold bleeding risk associated with GP IIb/IIIa inhibitor use (adjusted OR 1.39, 95% CI 0.96 to 2.03, p = 0.083). The small increase in absolute risk of bleeding from GP IIb/IIIa inhibitor use in this study is similar to the risk observed in clinical trials. Assuming these agents are as effective as shown in these trials, the risk-benefit ratio of GP IIb/IIIa inhibitors in broad-based PCI practice should be favorable.

Aged↗
PubMed2003

Limitations of current risk-adjustment models in the era of coronary stenting.

BACKGROUND: Several risk-adjustment models have been developed to compare outcomes of conventional coronary angioplasty across physicians and institutions. Yet the accuracy of these models in contemporary interventional practice--characterized by the widespread use of stents and novel adjuvant pharmacotherapies--has not been sufficiently studied. METHODS: The principal published predictive models for inhospital mortality after angioplasty were validated in 11,681 patients undergoing coronary stenting and 6475 patients undergoing balloon-only procedures in the Society for Cardiac Angiography and Interventions registry from July 1996 to December 1998. We examined the 2 components of model accuracy: discrimination, as determined by the c-index; and calibration, as measured by the Hosmer-Lemeshow statistic and predicted-versus-observed probability plots. RESULTS: The discriminative properties of the models were preserved in the validation cohort and did not differ statistically from one another (c-indexes 0.85-0.89). Hosmer-Lemeshow statistics, however, showed poor fit (P <.001), with all 3 models substantially overestimating the risk of adverse outcomes. Although recalibration of the models achieved satisfactory goodness of fit, laboratory-specific ratings differed depending on the model applied. CONCLUSIONS: Predictive models developed in the era of conventional angioplasty cannot be applied directly to current interventional practice. Although recalibration restores model fit, application of different recalibrated models yields inconsistent assessment of laboratory performance. Development of new, widely generalizable models is warranted, but such models will require continued reassessment as medical technology evolves and practice patterns change.

Aged↗
PubMed2002

Comparison of in-hospital and one-year outcomes in patients with and without diabetes mellitus undergoing percutaneous catheter intervention (from the National Heart, Lung, and Blood Institute Dynamic Registry).

Extrapolation of improvements in percutaneous coronary intervention (PCI) and outcomes to patients with diabetes has not been systematically examined in clinical practice. Two waves of consecutive patients (n = 4,629) who underwent PCI from July 1997 to June 1999 enrolled in the National Heart, Lung, and Blood Institute Dynamic Registry comprise the study population. There were 1,058 patients with treated diabetes and 3,571 patients without clinically evident diabetes. As a group, patients with diabetes tended to have more clinical, angiographic, and procedural risk factors. Although crude in-hospital mortality rates were higher in patients with diabetes (diabetics 2.3%, nondiabetics 1.3%; p = 0.02), the adjusted risk of in-hospital death (odds ratio 1.46, 95% confidence interval [CI] 0.80 to 2.66) was not significantly different. At 1 year, patients with diabetes had a significantly higher adjusted risk of mortality (risk ratio [RR] 1.80, 95% CI 1.35 to 2.41) and need for repeat revascularization (RR 1.40, 95% CI 1.13 to 1.74). There was a significant interaction between stent use and diabetic status with the need for repeat revascularization (adjusted RR in nondiabetics 0.73, 95% CI 0.61 to 0.88; adjusted RR in patients with diabetes 1.20, 95% CI 0.88 to 1.65). Beta blockers at the time of hospital discharge were significantly associated with reduced mortality rates at 1 year in both groups.

Age Factors↗
PubMed2002

Delivered dose and vascular response after beta-radiation for in-stent restenosis: retrospective dosimetry and volumetric intravascular ultrasound analysis.

BACKGROUND: Observations from previous intracoronary radiation therapy trials noted a considerable discrepancy between the prescribed radiation dose and the dose actually delivered. The aims of this study were to investigate the effect of actual delivered dose on vascular changes and to test the appropriateness of the current dose prescription. METHODS AND RESULTS: Serial volumetric intravascular ultrasound (IVUS) analysis was performed in 30 in-stent restenosis cases treated with a 40-mm (90)Sr/Y source train. The fixed dose was prescribed at 2 mm from the centerline of the source train (18.4 Gy at 2 mm for reference diameter < or =3.35 mm and 23 Gy for diameter > or =3.36 mm). Only stent segments with full radiation coverage and device injury were enrolled and divided into 2-mm-long subsegments (n=202). D(S90)EEM (the minimum dose absorbed by 90% of the external elastic membrane surface) was calculated as the delivered dose corresponding to each segment, assuming that the radiation catheter occupied the same position in the vessel as the IVUS catheter. Mean D(S90)EEM of 23.5+/-5.82 Gy (range 12.3 to 41.7 Gy) was delivered to these subsegments. Overall, intimal hyperplasia volume remained constant from postintervention to follow-up (2.23+/-1.10 to 2.32+/-1.09 mm3/m; P=NS). Regression analysis revealed there was no correlation between delivered dose intensity and changes in intimal hyperplasia volume. No particular dose-dependent complications were appreciated in this delivered dose range. CONCLUSIONS: The current dose-prescription protocol of (90)Sr/Y radiation to native in-stent restenosis lesions may provide substantial inhibition of neointimal reproliferation regardless of the actual delivered dose intensity.

Beta Particles↗
PubMed2002

Relation of percutaneous coronary intervention of complex lesions to clinical outcomes (from the NHLBI Dynamic Registry).

Advances in percutaneous coronary intervention (PCI) have reduced complications but expanded indications. We used the National Heart, Lung, and Blood Insitute Dynamic Registry to determine clinical outcomes up to 1 year after PCI in 2,839 patients with at least 1 treated complex lesion (defined as a lesion showing evidence of thrombus, calcification, bifurcation or ostial location, or chronic occlusion) and 1,790 patients with only simple lesions treated. Complex lesion interventions were associated (p <0.05) with more sustained major dissections, distal embolization, side branch occlusion, and persistent flow reduction. Patients with treated complex lesions had a lower procedural success rate (93.8% vs 97.3%, p <0.001) and increased in-hospital rates (p <0.001) of death (2.0% vs 0.6%), death/myocardial infarction [MI] (5.2% vs 2.4%), or death/MI/coronary artery bypass graft [CABG] surgery (6.5% vs 2.9%). After adjustment for potential confounders, patients treated for multiple complex lesions were more likely to experience the in-hospital combined end points of death/MI (odds ratio 3.22, 95% confidence interval 2.10 to 4.92), or death/MI/CABG (odds ratio 2.55, 95% confidence interval 1.71 to 3.80). At 1 year, patients with treated complex lesions were more likely (p <0.001) to die (6.2% vs 3.7%), suffer death/MI (11.7% vs 7.5%), or death/MI/CABG/repeat PCI (27.2% vs 23.4%). Patients treated for multiple complex lesions were approximately 50% more likely to die or to have major adverse events than with patients only treated for simple lesions. An increased in-hospital adverse clinical event rate was independently noted for thrombotic, bifurcation, and calcified lesions, and bifurcation lesions had worse long-term event rates.

Angioplasty, Balloon, Coronary↗
PubMed2002

Evaluation of the Society for Coronary Angiography and Interventions' lesion classification system in 14,133 patients with percutaneous coronary interventions in the current stent era.

We recently showed that the ACC/AHA coronary lesion classification could be simplified with no loss of predictive value (SCAI I = patent/non-C; SCAI II = patent/C; SCAI III = occluded/non-C; SCAI IV = occluded/C). We now test this system in a database reflecting current stent usage. Data from 14,133 patients with single-native-vessel interventions recorded in the Society for Coronary Angiography and Interventions (SCAI) Registry from July 1996 to July 1999 were analyzed. Stents were used in 60.2% of procedures. Logistic models predicting angiographic success suggested a slight, clinically insignificant preference for the SCAI classification (c-statistic = 0.692 vs. 0.670). Models using clinical variables to predict major complications were superior to models using only lesion classification. Lesion characteristics were related to outcomes primarily in elective (not acute myocardial infarction) patients. In the current PCI device era, the simpler SCAI classification using 7 variables predicted interventional success and complications as well as or better than the ACC/AHA system requiring 26.

Aged↗
PubMed2002

An unusual case of left internal mammary artery ostial disease: clarifying role of intravascular ultrasound.

Stenosis at the origin of the left internal mammary artery graft is rare. We present a case with a suspected stenosis involving the origin of the left internal mammary artery that conventional angiography failed to demonstrate convincingly. Intravascular ultrasound illustrated a severe stenosis and the patient underwent successful stenting of the left internal mammary artery origin. The intravascular ultrasound finding of a dissection flap, just distal to the left internal mammary artery origin, suggests that local trauma to the vessel from prior catheterization procedures may have been responsible for the progressive narrowing at the left internal mammary artery ostium.

Aged↗