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Lloyd W Klein

Publications and source records attributed to Lloyd W Klein.

54 records · Page 3Linked to original sources
PubMed2003

Improved in-hospital outcomes in acute coronary syndromes (unstable angina/non-ST segment elevation myocardial infarction) despite similar TIMI risk scores.

BACKGROUND: The Thrombolysis In Myocardial Infarction (TIMI) Risk Score has been shown to predict prognosis in acute coronary syndromes (ACS) comprised of unstable angina (UA) and non-ST segment elevation myocardial infarction (STEMI). We sought to evaluate the impact of newer antiplatelet and antithrombotic therapies for ACS, such as glycoprotein IIb/IIIa inhibitors (GPI) and low molecular weight heparin (LMWH), on in-hospital outcomes over time in patients (pts) with similar TIMI risk scores. METHODS: The baseline demographics and clinical outcomes of pts with ACS (UA and non-STEMI) in 1998 (Group 1998) and 2000 (Group 2000) at a single large university medical center were compared using a prospectively collected database. In-hospital major adverse cardiac events (MACE) included death, MI, or recurrent angina that resulted in urgent revascularization. Risk was estimated by utilizing the TIMI Risk Score, which uses 7 predictor variables: age > 65 years, at least 3 risk factors for coronary artery disease, prior coronary stenosis of 50%, ST segment deviation on EKG, severe angina, prior aspirin use, and elevated cardiac biomarkers. RESULTS: Comparing Group 1998 (n = 563) and Group 2000 (n = 604), there was no difference between the mean TIMI Risk Score (2.90 1.52 vs. 2.91 1.52; p = 0.97), demonstrating a similar risk profile. Nevertheless, significant improvement in in-hospital MACE (9.1% vs. 2.8%; p < 0.001) was noted. The improvement in MACE was due to differences in rates of recurrent angina, without significant differences in death and myocardial infarction. This occurred temporally in association with a significant increase in GPI (1.0% vs. 8.3%; p < 0.01) and LMWH (0.0% vs. 15.6%; p < 0.001) use within 24 hours of presentation, and the increased utilization of intracoronary stenting (46.6% vs. 64.6%; p = 0.005), findings which were confirmed with multivariate analysis. CONCLUSION: Despite similar TIMI Risk Scores, the in-hospital outcomes of pts with ACS have improved over time. This temporal change is associated with the greater use of newer antiplatelet and antithrombotic therapies and increased utilization of intracoronary stenting.

Aged↗
PubMed2003

Updated risk adjustment mortality model using the complete 1.1 dataset from the American College of Cardiology National Cardiovascular Data Registry (ACC-NCDR).

OBJECTIVES: To revise and update a risk adjustment model for in-hospital mortality following percutaneous coronary intervention (PCI) procedures using all data from the 1.1 version of the American College of Cardiology National Cardiovascular Data Registry (ACC-NCR). BACKGROUND: A model based on data received at the ACC-NCDR from 1998-2000 was previously reported. The revision of this mortality model reflects all of the data submitted using 1.1 data specifications and collected through the second quarter of 2001. The model was applied to selected high-risk subgroups from a sample of data collected during the year 2001 from version 2.0 of the NCDR. METHODS: Data on 173,743 PCI procedures collected at the ACC-NCDR between January 1, 1998 and March 31, 2001 were analyzed. A mortality model was generated as well as separate models for presentation with and without acute myocardial infarction within 24 hours. The model was used to generate predicted mortalities that were compared to observed mortalities in more current high-risk patient subgroups in the NCDR. RESULTS: The same factors that were previously found to be associated with increased risk of PCI mortality were re-verified in the current analysis. Inclusion of the complete 1.1 dataset produced some changes in the regression weights and the constant value. Excellent discrimination was achieved in the revised model (C-Index = 0.89). The model was applied to high-risk patient groups from data collected on 76,249 during the calendar year 2001 using the 2.0 NCDR data elements and definitions. These analyses showed a high level of agreement between observed mortality of each subgroup and the predicted mortality rates generated from the revised 1.1 PCI mortality model. CONCLUSIONS: Risk adjustment models for in-hospital mortality following PCI for all patients and for those with and without recent MI were regenerated using all data collected from the 1.1 data specifications of the ACC-NCDR and validated on high-risk groups from data collected during 2001 under data version 2.0 of the NCDR. These models reflect the most up-to-date analysis of mortality prediction from this large, multi-center national database.

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PubMed2002

Percutaneous coronary interventions in octogenarians in the American College of Cardiology-National Cardiovascular Data Registry: development of a nomogram predictive of in-hospital mortality.

OBJECTIVES: We sought to evaluate the results of percutaneous coronary intervention (PCI) in elderly patients in contemporary practice. BACKGROUND: Prior studies of PCI in the elderly population demonstrate increased in-hospital mortality, but these studies are limited by small population size. METHODS: Using the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) of 100,253 patients, the in-hospital outcomes in all 8,828 PCI procedures performed on octogenarians were evaluated. Patients underwent PCI between 1998 and 2000 at over 145 participating centers. RESULTS: The mean age was 83.72 +/- 3.02 years, with female preponderance (53%). The PCI was considered angiographically successful in 93%, stents were placed in 75%, and the post-PCI length of stay was 3.3 +/- 5.1 days. Overall in-hospital mortality was 3.77% but was only 1.35% in PCI without recent myocardial infarction (MI) within one week (p < 0.0001). Patients having PCI within 6 h of the onset of their MI had an increase in mortality tenfold (13.79%) compared with patients without a recent MI (p < 0.0001). All groups that were defined based on time of PCI after MI onset up to seven days had increased mortality (all p < 0.0001). Older age (odds ratio [OR] of 1.03 per incremental year), depressed ejection fraction (EF) (OR 0.69 per 10 points for EF <60%), and time of PCI after MI onset (<6 h, OR 6.87; 6 to 24 h, OR 5.66; 24 h to one week, OR 2.93) were most strongly predictive of outcome by multivariate analysis. The predicted mortality from the multivariate model correlated well with the observed in-hospital mortality up to 20% mortality. A 254-point nomogram was constructed employing the logistic model using a weighted point system. CONCLUSIONS: In patients > or = 80 years old, PCI has good success and acceptable mortality. The presence of an acute or recent MI substantially increases the risk of in-hospital death.

Age Factors↗
PubMed2002

Frequency of abrupt vessel closure and side branch occlusion after percutaneous coronary intervention in a 6.5-year period (1994 to 2000) at a single medical center.

The aims of this study were to analyze the contemporary trends in the changing incidence of abrupt vessel closure (AVC) after percutaneous coronary intervention (PCI), to determine the impact of intracoronary stenting and glycoprotein IIb/IIIa inhibitors (GPIs) on complication rates and etiologies, and to determine the incidence of side branch occlusion (SBO) as the etiology of AVC in the stent era, complications occurring during 3,300 consecutive PCIs performed from April 1994 to December 2000 at a single referral institution. In this consecutive patient cohort of PCI cases collected over a 6.5-year period, AVC occurred in 103 of 3,300 cases (3.12%). Linear regression analysis over this time frame documented a steadily decreasing incidence of AVC from 5.9% in 1994 to 1.1% in 2000 (-0.76%/per year, 95% confidence interval -0.99 to 0.52, p <0.05). Analysis using Pearson's correlation showed that the decreasing incidence of AVC was inversely correlated with the increasing percentage of intracoronary stents placed over this time period (r = -0.94, p <0.001). Additionally, GPI use increased from 0% in 1995 to 36.0% in 2000 (p = 0.009). The absolute incidence of SBO of a major branch vessel remained relatively stable over this 6.5-year period. However, SBO appeared to be increasing as the etiology of AVC, and accounted for 9.0% of AVC in 1995 compared with 28.0% of AVC in 2000. This increasing trend of the percentage of SBO as the etiology of AVC appeared to correlate with the increased use of stents (r = 0.85, p = 0.015). Thus, the incidence of AVC steadily decreased over the 6.5-year time period, and was associated with the increased use of stents and GPIs; conversely, SBO accounted for an increasing percentage of AVC over this time period.

Academic Medical Centers↗
PubMed2002

Development of a risk adjustment mortality model using the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) experience: 1998-2000.

OBJECTIVES: We sought to develop and evaluate a risk adjustment model for in-hospital mortality following percutaneous coronary intervention (PCI) procedures using data from a large, multi-center registry. BACKGROUND: The 1998-2000 American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) dataset was used to overcome limitations of prior risk-adjustment analyses. METHODS: Data on 100,253 PCI procedures collected at the ACC-NCDR between January 1, 1998, and September 30, 2000, were analyzed. A training set/test set approach was used. Separate models were developed for presentation with and without acute myocardial infarction (MI) within 24 h. RESULTS: Factors associated with increased risk of PCI mortality (with odds ratios in parentheses) included cardiogenic shock (8.49), increasing age (2.61 to 11.25), salvage (13.38) urgent (1.78) or emergent PCI (5.75), pre-procedure intra-aortic balloon pump insertion (1.68), decreasing left ventricular ejection fraction (0.87 to 3.93), presentation with acute MI (1.31), diabetes (1.41), renal failure (3.04), chronic lung disease (1.33); treatment approaches including thrombolytic therapy (1.39) and non-stent devices (1.64); and lesion characteristics including left main (2.04), proximal left anterior descending disease (1.97) and Society for Cardiac Angiography and Interventions lesion classification (1.64 to 2.11). Overall, excellent discrimination was achieved (C-index = 0.89) and application of the model to high-risk patient groups demonstrated C-indexes exceeding 0.80. Patient factors were more predictive in the MI model, while lesion and procedural factors were more predictive in the analysis of non-MI patients. CONCLUSIONS: A risk adjustment model for in-hospital mortality after PCI was successfully developed using a contemporary multi-center registry. This model is an important tool for valid comparison of in-hospital mortality after PCI.

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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.

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PubMed2002

Coronary angiographic morphology in unstable angina: comparative observations of culprit lesions in saphenous vein grafts versus native coronary arteries.

GOAL: To compare angiographic characteristics of culprit lesions in saphenous vein grafts (SVG) with those in native coronary arteries (NCA) in patients presenting with unstable angina (UA). METHODS: Over 4 years, a total of 445 consecutive patients undergoing coronary angiography and percutaneous coronary intervention during hospitalization for UA were identified using a prospectively collected database. Patients with enzyme or electrocardiographic (ECG) evidence for acute myocardial infarction were excluded. Single culprit lesions in SVGs were identified by angiographic and ECG criteria in 214 patients and in NCAs in 231 patients. Culprit lesions were clearly identifiable by clinical and angiographic correlation in all cases. Morphologic analysis of the culprit lesions was performed using the Ambrose classification. RESULTS: The SVG group had male predominance (86.4% vs. 66.7%; p = 0001) and was older (67.3 +/- 9.9 years vs. 64.0 +/- 12.2 years; p = 0.0017) compared to the NCA group. Left ventricular ejection fraction was lower in the SVG group (53.8 +/- 15.5% vs. 57.5 +/- 15.2%; p = 0.063). There was a higher incidence of thrombotic-appearing lesions in SVG culprit lesions than in NCAs (31.3% vs. 6.5%; p = 0.001). There was also a higher incidence of ulcerated plaque in SVGs (36.9% vs. 22.1%; p = 0.001). Total occlusions were more common in NCAs (13.0% vs. 7.9%; p = 0.084). The composite incidence of thrombus, ulcerated plaque and total occlusion was more frequent in SVG lesions (59.4% vs. 39.8%; p = 0.001). CONCLUSIONS: In UA, culprit lesions of SVGs assessed angiographically demonstrate morphology consistent with ulcerated plaque and thrombus more frequently than lesions in NCAs, but total occlusions are more common in NCAs. Angiographically-evident active thrombotic and ulcerated lesions underlie acute ischemic syndromes more frequently in SVGs than in native vessels.

Age Factors↗
PubMed2002

Report of an undeployed stent causing the unraveling of a coronary artery guidewire being used for sidebranch protection.

We report a case of a 70-year-old male who was undergoing elective angioplasty of the left anterior descending coronary artery. During the procedure, a coronary guidewire became unraveled after positioning an undeployed stent; we describe its successful retrieval by removal of the undeployed stent. Although sidebranch protection and placement of a stent with the guidewire left in place is commonly performed without complication, it should be realized that this practice is not without hazard because of the unusual, but serious consequences that could ensue if the entrapped wire were to unravel.

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PubMed2002

Supplemental value of troponin I combined with a clinical risk model to predict in-hospital events in intermediate and high risk patients with acute coronary syndromes.

To evaluate the supplemental value of serial troponin I (Trp) measurements when combined with a clinical model composed of six clinical parameters in predicting in-hospital adverse event rates, a total of 118 consecutive patients admitted over a 23-month period with intermediate- or high-risk unstable angina or non-Q wave myocardial infarction (MI) as defined by AHCPR criteria who had coronary angiography within 72 hours of hospitalization were studied. Presenting clinical characteristics were graded using a previously validated variation of the Braunwald criteria (RUSH model). The RUSH model clinical score includes six clinical parameters: age, diabetes, intravenous nitroglycerin, pre-admission calcium-channel and beta-blocker, ST depression and post-MI angina (< 2 weeks), and creates an estimated probability of MI or death. The RUSH model was compared to serial Trp levels drawn at 6-hour intervals (0, 6 and 12 hours). An abnormal Trp value was defined as > 2.0 mg/dl. Outcome measures included death, MI, recurrent chest pain and new ST or T changes and enzyme elevation. One death, 23 MIs and 24 other adverse clinical events occurred. The event group had a RUSH score predictive of 12.7 12.4% risk and the no-event group had a score of 13.2 10.2% risk (p = 0.64). The Trp positive group had a clinical score predicting 14.2 13.2% risk and the Trp negative group had a score of 11.7 9.3% risk (p = 0.21). Patients with elevated Trp had an adverse event rate of 32/50 (64%) vs. 21/68 (31%) in patients with normal Trp (p < 0.0004). Elevated Trp had 60.4% sensitivity and 72.3% specificity, odds ratio of 3.97 (1.71 9.33), as well as 64% positive and 69.1% negative predictive values for predicting adverse events. Thus, there was significant incremental value to adding Trp to the clinical score when predicting outcomes in patients with intermediate- and high-risk clinical scores. When Trp was abnormal, it was useful when predicting higher risk; if Trp was normal, it was useful predicting lower but still elevated risk. Consequently, in a population selected for intermediate and high risk, the presence or absence of elevated Trp I is a sensitive and specific additive predictor to clinical score to predict need for revascularization and adverse in-hospital outcomes, as suggested in current guidelines.

Aged↗
PubMedDate not supplied

Risk stratification post-myocardial infarction: is early coronary angiography the more effective strategy?

The primary management strategy for the post-myocardial infarction patient continues to be controversial despite published guidelines. In part, this is the consequence of study designs that are not directly applicable to individual patients, but also to the rapidly changing pharmacological and mechanical device armamentarium that rapidly renders clinical trial results obsolete within a few years. This review attempts to highlight those areas where there is consensus as well as to explicate those situations where common clinical practice appears to be in conflict with accepted guidelines.

Acute Disease↗
PubMedDate not supplied

Hormone therapy and selective estrogen receptor modulators for prevention of coronary heart disease in postmenopausal women estrogen replacement from the cardiologist's perspective.

Coronary heart disease is the leading cause of morbidity and mortality in women older than the age of 50 in the United States today. Traditional cardiovascular risk factors (hyperlipidemia, glucose intolerance, and hypertension) are more clearly associated with significant cardiovascular risk after menopause. The increased incidence of cardiovascular events in postmenopausal women and the evidence that cardiovascular disease on average manifests a decade later in women compared with men suggests that estrogen deficiency may predispose women to a higher cardiovascular risk. Numerous biologic mechanisms have been proposed that relate use of hormone therapy (HT) to improved lipid profiles, insulin sensitivity, and vascular reactivity. Early observational trials in the last 2 decades showed a significant decrease in cardiovascular events. Recently published randomized clinical trial results, however, have led to uncertainty about the earlier established cardiovascular benefits of HT. To complicate issues further, alternative estrogenlike compounds, selective estrogen receptor modulators, are being introduced that appear to convey similar cardiovascular benefit and notably less cancer risk than HT. The newly released randomized trials on hormone and nonhormonal agents are reviewed.

Coronary Disease↗