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Warren K Laskey

Publications and source records attributed to Warren K Laskey.

At least 19 recordsLinked to original sources

Prevention of contrast induced nephropathy: recommendations for the high risk patient undergoing cardiovascular procedures.

Contrast induced nephropathy (CIN) is the third leading cause of hospital acquired renal failure and is associated with significant morbidity and mortality. Chronic kidney disease is the primary predisposing factor for CIN. As estimated glomerular filtration rate<60 ml/1.73 m2 represents significant renal dysfunction and defines patients at high risk. Modifiable risk factors for CIN include hydration status, the type and amount of contrast, use of concomitant nephrotoxic agents and recent contrast administration. The cornerstone of CIN prevention, in both the high and low risk patients, is adequate parenteral volume repletion. In the patient at increased risk for CIN it is often appropriate to withhold potentially nephrotoxic medications, and consider the use of n-acetylcysteine. In patients at increased risk for CIN the use of low or iso-osomolar contrast agents should be utilized and strategies employed to minimize contrast volume. In these patients serum creatinine should be obtained forty-eight hours post procedure and it is often appropriate to continue withholding medications such as metformin or non steroidal anti-inflammatories until renal function returns to normal.

Contrast Media↗

Effect of gender on prognosis following percutaneous coronary intervention for stable angina pectoris and acute coronary syndromes.

Women with non-ST-elevation acute coronary syndromes (NSTACSs) may have better outcomes than men, but the effect of NSTACSs in women undergoing percutaneous coronary intervention (PCI) has not been examined. We performed a prospective, multicenter, cohort study of consecutive patients who underwent PCI for NSTACS and stable angina during 3 National Heart, Lung, and Blood Institute Dynamic Registry recruitment waves (1997 to 2002) to examine the effect of female gender on adverse clinical events after PCI or stable angina for NSTACS. The primary end point was the combined rate of death, myocardial infarction, or rehospitalization for cardiac causes at 1 year. Compared with men with NSTACS (n = 2,124), women (n = 1,338) were older and more often had hypertension, diabetes mellitus, and history of heart failure (p <0.001 for all), whereas multivessel disease was less frequent (p <0.01). Procedural success and in-hospital adverse event rates were similar. Women with NSTACS had the highest 1-year rate of death/myocardial infarction/cardiac rehospitalization compared with women with stable angina pectoris (n = 462) or men (n = 995; women with NSTACS 37.6%, men with NSTACS 29.8%, women with stable angina 29.4%, men with stable angina 27.7%, p <0.001). The higher rate remained after adjustment for differences in baseline characteristics (adjusted hazard ratio 1.37, 95% confidence interval 1.20 to 1.56). Among women, NSTACS conferred a significantly higher risk for adverse events compared with stable angina (adjusted hazard ratio 1.41, p = 0.001), whereas the risk of adverse events was not different in men (adjusted hazard ratio 1.05, p = 0.5). In conclusion, women undergoing PCI for NSTACS have a higher risk of major adverse cardiac events than men or women undergoing PCI for stable angina.

Aged↗

Variability in fluoroscopic X-ray exposure in contemporary cardiac catheterization laboratories.

OBJECTIVES: This study sought to assess fluoroscopic exposure rates in contemporary cardiac catheterization laboratories (CCL). BACKGROUND: Increasing attention is being focused on X-ray exposure during diagnostic and therapeutic cardiovascular procedures. METHODS: We measured fluoroscopic exposure rates (R/min) in 41 systems using a standardized methodology (National Electrical Manufacturers Association XR21 phantom). Measurements were obtained at 2 different phantom thicknesses to simulate varying patient body habitus. RESULTS: Fluoroscopic exposure rates under medium (median 3.0 R/min, interquartile range 1.4 R/min) and large (median 12.5 R/min, interquartile range 4.8 R/min) habitus conditions showed substantial variation. Fluoroscopic exposure was associated with simulated patient habitus, X-ray system type, vendor, and geographic region. Under medium habitus conditions, only 25% of systems operated within a zone of lower than average exposure rates and satisfactory image quality; this frequency diminished to 7% under large habitus conditions (p < 0.001). CONCLUSIONS: There is substantial variation (4- to 6-fold) in fluoroscopic exposure rates. This variation was not consistently associated with improved image quality. In the absence of a predictable benefit of higher (or lower) than average exposure rates, CCL quality improvement programs must minimize such potentially harmful variability in X-ray exposure.

Cardiac Catheterization↗

Outcome of percutaneous coronary intervention in unstable angina pectoris versus stable angina pectoris in two different time periods.

Percutaneous coronary intervention (PCI) for unstable angina pectoris (UAP) has traditionally been associated with a higher risk of ischemic complications than that for stable angina pectoris (SAP). However, PCI procedures have evolved, so this study was designed to determine whether PCI for UAP is still associated with less favorable outcomes. In-hospital and 1-year outcomes in Dynamic Registry patients who presented for PCI with UAP (n = 2,994) or SAP (n = 1,457) between 1997 and 2002 were compared. One-year results were also compared with consecutive patients who underwent angioplasty (n = 2,431) from the 1985 to 1986 Percutaneous Transluminal Coronary Angioplasty Registry. Although Dynamic Registry patients with UAP were older and more likely to smoke (p < 0.05), have diabetes mellitus (p = 0.03), or a previous myocardial infarction (p < 0.001), procedural success was higher than in patients with SAP. By 1 year, there was greater risk of death (4.4% vs 2.6%, p < 0.01), death/myocardial infarction (9.9% vs 6.6%, p < 0.001), and death, myocardial infarction, and coronary artery bypass grafting (15.1% vs 11.6%, p < 0.01) in patients with UAP. In patients with UAP, there was no significant difference in adjusted 1-year death and death/myocardial infarction rates when comparing the waves of the Dynamic Registry with those of the Percutaneous Transluminal Coronary Angioplasty Registry, although death/myocardial infarction rates among Dynamic Registry patients were lower. However, in patients with SAP, the adjusted rate for death/myocardial infarction was lower in wave 3, and for death, myocardial infarction, and revascularization, there was a significant decrease in event rates with each successive recruitment period (p < 0.05 for all comparisons). In conclusion, in contradistinction to patients with SAP, death and death/myocardial infarction rates in patients who have undergone PCI for UAP have not significantly decreased over the past 16 years and patients with UAP remain at a greater risk of ischemic events at 1 year compared with patients with SAP.

Angina, Unstable↗

Quality management and volume-related outcomes in the cardiac catheterization laboratory.

The assessment of quality in the cardiac catheterization laboratory is a complex, ongoing process that requires a comprehensive analysis of the multiple elements of quality. Although clinical outcomes are a reflection of the quality process, they derive from a complex interaction of clinical, technical, and process-of-care components. Procedural volume is associated but not equated with clinical outcomes, although the magnitude of this association depends on numerous covariates, most notably the diminishing rate of adverse outcomes over time.

Cardiac Catheterization↗

Marked improvements in outcomes of contemporary percutaneous coronary intervention in patients with diabetes mellitus.

We sought to determine if advances in percutaneous coronary intervention (PCI) are associated with better outcomes among patients with diabetes mellitus (DM). Patients with DM enrolled in the National Heart, Lung, and Blood Institute (NHLBI) early PTCA Registry (1985-1986) were compared to those in the subsequent contemporary Dynamic Registry (1999-2002) for in-hospital and one-year cardiovascular outcomes. The study population included 945 adults with DM, 325 from the PTCA Registry and 620 from the Dynamic Registry. Multivariable Cox regression models were built to estimate the risk of clinical events. Dynamic Registry patients were older, had more noncardiac comorbidities, and a lower mean ejection fraction (50.5% vs 57.8%, P < or = 0.001) compared to the PTCA Registry patients. The incidence of in-hospital mortality (1.9% vs 4.3%, P < or = 0.05), myocardial infarction (MI) (1.0% vs 7.4%, P <or = 0.001), and coronary artery bypass grafting (CABG) (0.8% vs 6.2%, P < or = 0.001) were all significantly lower and independent of the use of stents. One-year adverse events including MI (4.9% vs 11.0%, P < or = 0.001), CABG (6.4% vs 15.0%, P < or = 0.001), and need for repeat revascularization (18.7% vs 33.3%, P < or = 0.001) were all lower in the Dynamic Registry. The relative risk of death at 1 year was significantly less for patients in the Dynamic Registry (RR 0.56, 0.34; 0.92, P = 0.02). Although Dynamic Registry patients with diabetes had more advanced coronary disease, in-hospital and late adverse events were lower. A combination of the use of stents and an increase in adjunctive medical therapy are likely responsible for the observed improvements in outcomes in contemporary PCI.

Angioplasty, Balloon, Coronary↗

Importance of the postdischarge interval in assessing major adverse clinical event rates following percutaneous coronary intervention.

In-hospital major adverse clinical event (MACE) rates after percutaneous coronary intervention serve as benchmarks of performance. However, accelerated clinical pathways, decreased lengths of stay, and potential delayed effects of percutaneous coronary intervention may result in an underestimation of this traditional measurement of outcome. Records from patients in the first 3 waves of the National Heart, Lung, and Blood Institute's Dynamic Registry (n = 6,676) were reviewed for rates of composite in-hospital MACEs (death, myocardial infarction, and any repeat target vessel revascularization) and postdischarge MACEs (death, myocardial infarction, repeat hospitalization, and repeat target vessel revascularization) through 30 days. Rates for each composite MACE were compared across waves to assess changes over time. Predictors of each MACE category were identified using multivariate analysis. In-hospital MACE decreased significantly (5.4% of wave 1, 4.9% of wave 2, 3.1% of wave 3, p <0.001), whereas stent implantation increased significantly (67.5% of wave 1, 79.1% of wave 2, 86.2% of wave 3, p <0.001). Postdischarge MACE through 30 days remained unchanged (5.1% of wave 1, 5.1% of wave 2, 4.8% of wave 3, p = 0.6). Mean length of stay decreased (2.7 days for wave 1, 2.2 days for wave 3, p <0.001). Disparate clinical, procedural, and angiographic factors were associated with each MACE. Postdischarge MACE rates through 30 days comprise a significant and unchanging fraction of overall procedurally related MACE rates despite improving in-hospital outcomes. Most postdischarge events derive from pathology related to the controlled vessel. A 30-day MACE rate may serve as a more comprehensive measurement of procedural outcome.

Aged↗

Brief repetitive balloon occlusions enhance reperfusion during percutaneous coronary intervention for acute myocardial infarction: a pilot study.

The objective of this study was to determine whether acutely ischemic myocardium may be conditioned during percutaneous coronary intervention for acute myocardial infarction. Ischemic preconditioning is a powerful cardioprotective mechanism that limits infarct size in animal investigations and ischemic sequelae during percutaneous coronary intervention in man. However, the conditioning stimulus in all these studies has been applied prior to the defining episode of ischemia. Seventeen patients undergoing percutaneous coronary intervention for acute myocardial infarction were randomly assigned to a standard ischemic preconditioning protocol (n = 10) or a usual-care control group (n =7). ST segment shift response and Doppler-derived distal coronary velocity data were compared. Despite similar degrees of baseline ST segment elevation, the magnitude of final ST segment elevation in the conditioning group was less than that in controls at the protocol conclusion (conditioning, 1.60 +/- 0.8 mV; control, 4.0 +/- 0.5 mV; P < 0.001). The rate of ST segment resolution was greater in the conditioning group (conditioning, 0.28 +/- 0.1 mV/min; control, 0.12 +/- 0.1 mV/min; P = 0.02). Distal coronary velocimetry indicated significant improvement in coronary flow velocity reserve in the conditioning group at the protocol conclusion (conditioning, 1.8 +/- 0.2; control, 1.4 +/- 0.1; P < 0.008). Brief periods of occlusion and reperfusion during percutaneous intervention for acute myocardial infarction mitigate the extent of ischemic injury and improve distal myocardial perfusion. Such ischemic conditioning represents a potentially useful adjunct to strategies for enhancing reperfusion during acute myocardial infarction.

Adult↗

Temporal variation in inhospital mortality with percutaneous coronary intervention: a report from the National Heart, Lung and Blood Institute Dynamic Registry.

BACKGROUND: Cardiovascular morbidity and mortality display a distinct time dependence also known as circadian variation. Whether such time dependence extends to the risk of procedural-related mortality after percutaneous coronary intervention (PCI) is presently unknown. METHODS: Inhospital mortality was analyzed in 6,347 patients with PCI start times from 8:00 am to 6:59 pm ("usual" workday). The sample was divided into 3 evenly populated groups (morning start 8:00-10:59 AM, midday start 11:00 AM-1:59 PM, afternoon start 2:00-6:59 PM). The association between procedural start time and mortality was assessed using multivariable analysis including a propensity score accounting for factors associated with procedural start time. RESULTS: There was a significant, nonlinear relationship between procedural-related mortality and start time (P = .03). Afternoon start patients were at higher adjusted risk of mortality compared with midday start patients (OR 2.03, 95% CI 1.07-3.83, P = .03 ). Morning start patients were also at higher risk compared with midday start patients although the association was not statistically significant (OR 1.73, 95% CI 0.89-3.39, P = .11). CONCLUSIONS: There is a significant time-dependent variation in the risk of inhospital PCI-related mortality during usual working hours. The highest risk period, taking into account numerous factors that confound this association, is the latter part of the workday. A second period of apparent greater risk occurs during the early part of the workday and is consistent with our present understanding of circadian variation in cardiovascular disease processes.

Aged↗