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Lloyd W Klein

Publications and source records attributed to Lloyd W Klein.

At least 19 recordsLinked to original sources
PubMed2006

Risk-adjusted mortality analysis of percutaneous coronary interventions by American College of Cardiology/American Heart Association guidelines recommendations.

An American College of Cardiology (ACC)/American Heart Association (AHA) task force on practice guidelines in 2001 published evidence-based recommendations for performing percutaneous coronary interventions (PCIs). These guidelines grouped the indications for PCI into 4 classes (I, IIa, IIb, and III) based on analyses of risks and benefits. In a previous study, we found that clinical success and in-hospital adverse events varied by indications class. However, no adjustment for risk was used in those comparisons. The ACC/National Cardiovascular Data Registry (ACC-NCDR) previously developed a risk-adjustment model for the adverse event of in-hospital PCI mortality. We investigated how the 14 individual risk factors in the ACC-NCDR PCI mortality model might differ across the 4 indications classes and whether estimated mortality for each class approximated the observed mortality for that class. We analyzed the ACC-NCDR PCI database for January 1, 2001 to December 31, 2004. We excluded procedures performed for treatment of acute ST-segment elevation myocardial infarction; all others were included, yielding 559,273 procedures for analysis. An algorithm derived from the 2001 guidelines was used to assign procedures to an indications class. Increasing frequencies of risk components were observed across classes I, IIa, IIb, and III. Expected mortalities for each class calculated by the risk-adjustment model were close to observed values (expected 0.52%, 0.59%, 1.72%, and 1.96%, respectively; observed 0.49%, 0.63%, 1.88%, and 1.60%, respectively). In conclusion, the ACC-NCDR risk-adjusted mortality model can be linked to the ACC/AHA PCI guidelines, and together these produce mortality risk estimates by indications classes that are close to actual observed values. With further refinement, these methods should be able to be used as powerful analytic tools for quality assurance and appropriateness purposes.

Aged↗
PubMed2006

On- versus off-label use of drug-eluting coronary stents in clinical practice (report from the American College of Cardiology National Cardiovascular Data Registry [NCDR]).

Limited data are available on the off-label use of drug-eluting stents (DESs) in clinical practice. We used data from the American College of Cardiology National Cardiovascular Data Registry to describe the rates and outcomes of DES use in 4 common off-label situations: ST-elevation myocardial infarction, in-stent restenosis, coronary artery bypass grafts, and chronic total occlusions. The rates of in-hospital adverse events for each off-label situation were determined and compared with the expected rates calculated from a validated model. From approval of DESs to the end of 2004, a total of 408,033 procedures involved placement of a DES. The use of DESs increased from 19.7% at the start of the study to 78.2% by the end of fourth quarter of 2004. Off-label use of DESs occurred in 24.1% of procedures. The rates of in-hospital adverse events with DES use in ST-elevation myocardial infarction, in-stent restenosis, coronary artery bypass grafting, and chronic total occlusions were lower than expected from the validated model. In conclusion, off-label use of DESs is common and is associated with a low rate of short-term adverse events. Randomized clinical trials are needed to confirm the efficacy of DESs in these clinical and angiographic settings. These data also highlight the importance of multicenter registries in tracking new technologies.

Coronary Artery Bypass↗
PubMed2006

Ad hoc percutaneous coronary interventions in patients with stable coronary artery disease--a study of prevalence, safety, and variation in use from the American College of Cardiology National Cardiovascular Data Registry (ACC-NCDR).

OBJECTIVE: To utilize the American College of Cardiology National Cardiovascular Data Registry (ACC-NCDR) to monitor the performance and safety of ad hoc PCIs. BACKGROUND: The performance of ad hoc PCI remains controversial. Patients' preference, cost, and vascular access issues favor an ad hoc strategy. Adequate time for thoughtful decision-making, scheduling complexity, informed consent, and physician reimbursement favor PCI on a subsequent day. METHODS: We analyzed results in 68,528 patients with stable angina entered in the ACC-NCDR from 2001-2003. Ad hoc PCI was evaluated in many clinical and nonclinical subgroups. A multivariable analysis was performed to determine whether ad hoc PCI had an independent relationship with complications or procedure success. RESULTS: Overall, 60.6% of patients underwent ad hoc PCI. There was no difference in ad hoc PCI mortality, renal failure, or vascular complications from staged PCI. A lower percentage of patients at high vs. low risk and with vs. without renal failure underwent ad hoc PCIs (58.6% vs.63.0% and 50.7% vs. 60.9% respectively). There was wide variation in the performance of ad hoc PCIs according to payer (70.2-60.3%), hospital PCI volume (67-50.2%), hospital owner (89.7-59.6%), and geographic area (75.5-47.4%). Ad hoc PCI per se was not independently related to PCI success or complications. CONCLUSIONS: PCI success was related to patient/lesion related factors and not to the performance of ad hoc PCIs per se. Although ad hoc PCI can be performed in more patients than at present, this strategy will never be possible in all patients at all times.

Aged↗
PubMed2006

Patterns and outcomes of drug-eluting coronary stent use in clinical practice.

OBJECTIVE: To determine patterns and outcomes of drug-eluting stents (DES) use in clinical practice. BACKGROUND: DES are technology associated with superior outcomes. The initial limited availability and high cost of DES had the potential to influence their use. METHODS: Data from the American College of Cardiology-National Cardiovascular Data Registry were examined to describe the patterns of DES use in 408,033 percutaneous coronary intervention (PCI) procedures at 383 sites. Predictors of DES use were determined, and inhospital outcomes were examined. RESULTS: From April 2003 through December 2004, the proportion of procedures using DES increased from 19.7% to 78.2%. DES use increased across all patient groups and hospital types, but adoption was slower among older patients and those without health insurance. DES use varied among hospitals such that use was lower at rural and low-volume hospitals. Multivariable regression demonstrated a progressive decrease in the odds of DES use as age increased. White race, female sex, presence of insurance, diabetes mellitus, PCI of de novo lesion, PCI at a high volume center, and PCI at a suburban hospital were significant predictors of DES use. The availability of a second DES product did not influence the adoption patterns. Inhospital outcomes with DES were excellent. CONCLUSIONS: Access to DES was influenced by demographic, socioeconomic, and hospital characteristics. Further study is needed to determine if the availability of another DES platform or increased overall availability of DES impacts favorably on PCI practice patterns.

Adult↗
PubMed2006

Clinical and economic outcomes of embolic complications and strategies for distal embolic protection during percutaneous coronary intervention in saphenous vein grafts.

BACKGROUND: Although distal embolic protection (DEP) is increasingly utilized in saphenous vein graft percutaneous coronary intervention (SVG PCI), the clinical and economic outcomes of different DEP strategies are unknown. METHODS: We compared 3 DEP strategies (no DEP, routine DEP, selective DEP in high-risk cases) in 126 consecutive cases of SVG PCI performed without DEP in a single catheterization laboratory over a 4-year period. No SVG PCI was excluded. High risk was defined using 2 multivariate predictors of embolic complication previously validated by NCDR (graft age greater than or equal to 8 years and or friable appearance with thrombus). Costs were determined by a ratio of cost-to-charges methodology and average cost of the two FDA-approved DEP devices ($1,350) with similar efficacy. RESULTS: Without DEP, the incidence of embolic complications was 17% (22/126), resulting in major adverse coronary events (MACE) in 3.2% (4/126) of all cases: 2 deaths, 1 myocardial infarction, and 1 emergency coronary artery bypass. Embolic complications significantly increased both procedure costs by $2,725 (p < .001) and total hospital costs approximately $2,800 (p < 0.05). Risk adjustment for selective DEP use correctly predicted 86% (19/22) of embolic complications, including all MACE, at an incremental cost of $684 per patient for selective DEP versus $1,150 per patient for routine DEP. Selective DEP would cost $43,127 per death prevented versus $72,461 using routine DEP during the index hospitalization. CONCLUSIONS: Embolic complications increase cost in excess of the cost of a DEP device. This risk adjustment model correctly predicted the majority of cases of embolic complication and all MACE, suggesting that selective DEP use may help reduce utilization of DEP by an almost 50% cost reduction compared to routine use.

Aged↗
PubMed2005

Are drug-eluting stents the preferred treatment for multivessel coronary artery disease?

Drug-eluting stents (DES) constitute a major breakthrough in restenosis prevention after initial percutaneous coronary intervention (PCI). Target lesion and vessel revascularization rates of <10% at six months follow-up represent a significant medical advance. Many cardiologists consider it reasonable to assume that PCI using DES ought to be considered equivalent, if not superior, to bypass surgery. The argument made is that in previous randomized clinical trials comparing PCI to coronary artery bypass grafting, restenosis was the determining factor favoring surgery, an event that clinical experience suggests is no longer as frequent. In the absence of a definitive clinical trial to support this view, how should the prudent, cutting edge cardiologist evaluate the data and manage their patients?

Angioplasty, Balloon, Coronary↗
PubMed2005

Relationship between procedure indications and outcomes of percutaneous coronary interventions by American College of Cardiology/American Heart Association Task Force Guidelines.

BACKGROUND: An American College of Cardiology/American Heart Association (ACC/AHA) Task Force periodically revises and publishes guidelines with evidence-based recommendations for appropriate use of percutaneous coronary intervention (PCI). Some studies have suggested that closer adherence to guidelines can reduce variations in care, can improve quality, and may ultimately result in better outcomes, but this finding is incompletely understood. Guidelines themselves must change to be responsive to continuously evolving clinical practice. Our goal here was to investigate whether any relationship existed between the most recent ACC/AHA recommended indications for PCI and short term in-hospital outcomes. METHODS AND RESULTS: We analyzed the ACC National Cardiovascular Data Registry for the period of January 1, 2001, through March 31, 2004. We excluded PCI procedures performed for acute myocardial infarction (ST-segment elevation myocardial infarction); all others were grouped by their indications according to the standard ACC/AHA scheme: Class I, evidence and/or agreement that PCI is useful and effective; Class IIa, conflicting evidence and/or divergent opinions, weight is in favor; Class IIb, usefulness/efficacy is less well established; and Class III, evidence and/or agreement that PCI is not useful or effective and may be harmful. Clinical success was defined as angiographic success (<20% residual stenosis) at all lesions attempted without the adverse events of myocardial infarction, same-admission bypass surgery, or death. There were 412 617 PCI procedures included in the analysis. Frequency of indications was as follows: Class I, 64%; Class IIa, 21%; Class IIb, 7%; and Class III, 8%. Clinical success declined across the indications classes (92.8%, 91.7%, 89%, and 85.5%, respectively; P<0.001), whereas adverse events increased. CONCLUSIONS: In this large survey of contemporary PCI practice, most procedures were performed for Class I indications. A significant relationship between evidence-based indications recommended by the ACC/AHA Task Force and in-hospital outcomes was noted.

Angioplasty, Balloon, Coronary↗
PubMed2005

Mortality after emergent percutaneous coronary intervention in cardiogenic shock secondary to acute myocardial infarction and usefulness of a mortality prediction model.

Although percutaneous coronary intervention (PCI) in the setting of cardiogenic shock has a high in-hospital mortality rate, it has been shown to decrease the mortality rate in certain subgroups. The identity and relative importance of variables that are predictive of in-hospital mortality rate after PCI for cardiogenic shock are uncertain. Accordingly, we examined data of >300,000 patients in the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) that were collected from 1998 to 2002 and evaluated the outcomes in 483 consecutive patients who underwent emergency PCI for cardiogenic shock. Patients' mean age was 65 +/- 13 years, with men predominating (61%). All underwent emergency/salvage PCI in the setting of cardiogenic shock after acute myocardial infarction. Mean left ventricular ejection fraction was 30 +/- 16%. Stents were placed in 64% of patients, and thrombolytic agents were administered in 26%. Although PCI was angiographically successful in 79% of patients, the in-hospital mortality rate was 59.4%. Length of stay after PCI was 7.2 +/- 8 days. Logistic regression using all available variables identified 6 multivariate predictors of death: age (odds ratio [OR] 2.34, 95% confidence interval [CI] 1.68 to 3.28, p <0.001) for each 10-year increment, female gender (OR 1.55, 95% CI 1.00 to 2.41, p <0.001), baseline renal insufficiency (creatinine >2.0 mg/dl; OR 4.69, 95% CI 1.96 to 11.23, p <0.001), total occlusion in the left anterior descending artery (OR 1.99, 95% confidence interval 1.28 to 3.09, p <0.01), no stent used (OR 2.55, 95% CI 1.63 to 3.96, p <0.01), and no glycoprotein IIb/IIIa inhibitor used during PCI (OR 1.96, 95% CI 1.30 to 2.98, p <0.01). In a second analysis using only variables known to the clinician at the time of initial presentation, gender, age, renal insufficiency, and total occlusion of the left anterior descending coronary artery were significant. In conclusion, analysis of patients from the ACC-NCDR who underwent emergency PCI for acute myocardial infarction in the presence of cardiogenic shock shows an in-hospital mortality rate of approximately 60% when PCI is attempted.

Age Factors↗