R-wave amplitude changes measured by electrocardiography during early transmural ischemia.

BACKGROUND: Changes in the amplitude of the R wave (RWA) on the electrocardiogram (ECG) have been described during acute myocardial ischemia and infarction. However, this has not been well studied in a controlled setting. We hypothesized that significant increase in RWA occurs during early transmural myocardial ischemia. METHODS: We prospectively evaluated changes in RWA in 50 patients during brief episodes of transmural ischemia induced by first balloon occlusion (mean, 38 seconds at 6-10 atmospheric pressures) during elective percutaneous coronary intervention. We recorded 12-lead ECGs at 20-second intervals before and during balloon inflation in 16 right coronary arteries, 14 left circumflex arteries, and 20 left anterior descending arteries. R wave amplitude was digitally measured in each of the 12 leads in every ECG using the ECG interval editor (General Electric HC, Menomonee Falls, WI). Intracoronary (IC) ECGs were also recorded in 4 patients. The mean of the RWA in each lead before balloon inflation was compared to the mean RWA during balloon inflation. RESULTS: R wave amplitude significantly increased during balloon inflation from baseline in limb leads I, II, aVL, and all the precordial leads with the exception of lead V(1). The RWA increase did not reach statistical significance in leads III, aVF, and V(1). Mean RWA increase was consistent in all leads except aVR during the brief episodes of ischemia during initial balloon inflation because of the inverse polarity of this lead. The increase in RWA was seen in most patients (mean, 75%) in whom transmural ischemia was induced by first balloon inflation. Besides, the RWA showed an increase from baseline in 3 patients who had IC-lead recordings. CONCLUSION: R wave amplitude increases significantly in precordial leads (V(2)-V(6)) and limb leads (I, II, aVL) of the surface ECG during brief episodes of transmural ischemia. The increase in RWA might be consistent with the expansion of the left ventricular cavity during ischemia and/or alterations in conduction that are intrinsic to the myocardium.

Prevalence, predictors, and outcomes of premature discontinuation of thienopyridine therapy after drug-eluting stent placement: results from the PREMIER registry.

BACKGROUND: Although drug-eluting stents (DES) significantly reduce restenosis, they require 3 to 6 months of thienopyridine therapy to prevent stent thrombosis. The rate and consequences of prematurely discontinuing thienopyridine therapy after DES placement for acute myocardial infarction (MI) are unknown. METHODS AND RESULTS: We used prospectively collected data from a 19-center study of MI patients to examine the prevalence and predictors of thienopyridine discontinuation 30 days after DES treatment. We then compared the mortality and cardiac hospitalization rates for the next 11 months between those who stopped and those who continued thienopyridine therapy. Among 500 DES-treated MI patients who were discharged on thienopyridine therapy, 68 (13.6%) stopped therapy within 30 days. Those who stopped were older, less likely to have completed high school or be married, more likely to avoid health care because of cost, and more likely to have had preexisting cardiovascular disease or anemia at presentation. They were also less likely to have received discharge instructions about their medications or a cardiac rehabilitation referral. Patients who stopped thienopyridine therapy by 30 days were more likely to die during the next 11 months (7.5% versus 0.7%, P<0.0001; adjusted hazard ratio=9.0; 95% confidence interval=1.3 to 60.6) and to be rehospitalized (23% versus 14%, P=0.08; adjusted hazard ratio=1.5; 95% confidence interval=0.78 to 3.0). CONCLUSIONS: Almost 1 in 7 MI patients who received a DES were no longer taking thienopyridines by 30 days. Prematurely stopping thienopyridine therapy was strongly associated with subsequent mortality. Strategies to improve the use of thienopyridines are needed to optimize the outcomes of MI patients treated with DES.

Association of a continuous quality improvement initiative with practice and outcome variations of contemporary percutaneous coronary interventions.

BACKGROUND: The objective of this study was to evaluate the association of a continuous quality improvement program with practice and outcome variations of percutaneous coronary intervention (PCI). METHODS AND RESULTS: Data on consecutive PCI were collected in a consortium of 5 hospitals; 3731 PCIs reflected care provided at baseline (January 1, 1998, to December 31, 1998), and 5901 PCIs reflected care provided after implementation of a continuous quality improvement intervention (January 1, 2002, to December 31, 2002). The intervention included feedback on outcomes, working group meetings, site visits, selection of quality indicators, and use of bedside tools for quality improvement and risk assessment. Postintervention data were compared with baseline and with 10,287 PCIs from 7 hospitals added to the consortium in 2002. Quality indicators included use of preprocedural aspirin or clopidogrel, use of glycoprotein IIb/IIIa receptor blockers and postprocedural heparin, and amount of contrast media per case. Outcomes selected included emergency CABG, contrast nephropathy, myocardial infarction, stroke, transfusion, and in-hospital death. Compared with baseline and the control group, the intervention group at follow-up had higher use of preprocedural aspirin and glycoprotein IIb/IIIa blockers, lower use of postprocedural heparin, and a lower amount of contrast media per case (P<0.05). These changes were associated with lower rates of transfusions, vascular complications, contrast nephropathy, stroke, transient ischemic attack, and combined end points (all P<0.05). CONCLUSIONS: Our nonrandomized, observational data suggest that implementation of a regional continuous quality improvement program appears to be associated with enhanced adherence to quality indicators and improved outcomes of PCI. A randomized clinical trial is needed to determine whether this is a "causal" or a "casual" relationship.

The efficacy and safety of combination glycoprotein IIbIIIa inhibitors and reduced-dose thrombolytic therapy-facilitated percutaneous coronary intervention for ST-elevation myocardial infarction: a meta-analysis of randomized clinical trials.

OBJECTIVE: We reviewed the literature and performed a meta-analysis comparing the safety and efficacy of adjunctive use of reduced-dose thrombolytics and glycoprotein (Gp) IIbIIIa inhibitors to the sole use of Gp IIbIIIa inhibitors before percutaneous coronary intervention (PCI) in patients presenting with acute ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Early reperfusion in STEMI is associated with improved outcomes. The use of reduced-dose thrombolytic and Gp IIbIIIa inhibitors combination before PCI in the setting of acute STEMI remains controversial. METHODS: We performed a literature search and identified randomized trials comparing the use of combination therapy-facilitated PCI versus PCI done with Gp IIbIIIa inhibitor alone. Included studies were reviewed to determine Thrombolysis in Myocardial Infarction (TIMI)-3 flow at baseline, major bleeding, 30-day mortality, TIMI-3 flow after PCI, and 30-day reinfarction. We performed a random-effect model meta-analysis. We quantified heterogeneity between studies with I2. A value >50% represents substantial heterogeneity. RESULTS: We identified 4 clinical trials randomizing 725 patients; 424 patients were pretreated with combination therapy before PCI, and 301 patients had Gp IIbIIIa inhibitor alone during PCI. Combination therapy-facilitated PCI was associated with a 2-fold increase in TIMI-3 flow upon arrival to the catheterization laboratory compared with the sole use of upstream Gp IIbIIIa inhibitors (192/390 patients [49%] versus 60/284 [21%]; relative risk [RR], 2.2; P < .00001). However, post-PCI TIMI-3 flow was similar between the 2 groups (279/319 patients [87%] versus 188/212 [88%]; RR, 0.99; P = .85). Major bleeding events significantly increased in the combination therapy group (40/420 patients [9.5%] versus 14/299 [4.7%]; RR, 2.2; P = .007). The 30-day mortality (15/424 patients [3.5%] versus 5/301 [1.7%]; RR, 1.47; P = .46) and 30-day reinfarction rate (5/424 patients [1.1%] versus 3/301 [1.0%]; RR, 0.96; P = .96) were similar in the 2 treatment groups. CONCLUSIONS: Awaiting the results of the ongoing clinical trials, the current cumulative evidence does not support the routine use of combination of reduced-dose thrombolytic and Gp IIbIIIa inhibitor therapy-facilitated PCI for the treatment of STEMI.

Left atrial reverse remodeling in dogs with moderate and advanced heart failure treated with a passive mechanical containment device: an echocardiographic study.

BACKGROUND: Assessment of global left ventricular (LV) remodeling is important in evaluating the efficacy of pharmacologic and device therapies for the treatment of chronic heart failure (HF). The effects of pharmacologic or device therapies on global left atrial (LA) remodeling in HF, although also important, are not often examined. We showed that long-term therapy with the Acorn Cardiac Support Device (CSD), a passive mechanical ventricular containment device, prevents or reverses LV remodeling in dogs with HF. This study examined the effects of the CSD on global LA remodeling in dogs with moderate and advanced HF. METHODS AND RESULTS: Studies were performed in 24 dogs with coronary microembolization-induced HF. Of these, 12 had moderate HF (ejection fraction, EF 30% to 40%) and 12 advanced HF (EF < or = 25%). In each group, the CSD was implanted in 6 dogs and the other 6 served as controls. Dogs were followed for 3 months in the moderate group and 6 months in the advanced HF group. LA maximal volume (LAVmax), LA volume at the onset of the p-wave (LAVp), LA minimal volume (LAVmin), LA active emptying volume (LAAEV), and LA active emptying fraction (LAAEF) were measured from 2-dimensional echocardiograms obtained before CSD implantation and at the end of the treatment period. Treatment effect (delta) comparisons between CSD-treated dogs and controls showed that CSD therapy significantly decreased LA volumes (deltaLAVmax: 3.33 +/- 0.70 vs. -2.87 +/- 1.31 mL, P = .002; 7.77 +/- 1.76 versus -0.37 +/- 0.87 mL, P = .002) and improved LA function (deltaLAAEF: -6.00 +/- 1.53 versus 1.85 +/- 1.32%, P = .003; -2.39 +/- 1.10 versus 3.13 +/- 1.66%, P = .02) in the moderate HF and advanced HF groups, respectively. CONCLUSIONS: Progressive LA enlargement and LA functional deterioration occurs in untreated dogs with HF. Monotherapy with the CSD prevents LA enlargement and improves LA mechanical function in dogs with moderate and advanced HF indicating prevention or reversal of adverse LA remodeling.

A meta-analysis of randomized control trials comparing minimally invasive direct coronary bypass grafting versus percutaneous coronary intervention for stenosis of the proximal left anterior descending artery.

Percutaneous intervention (PCI) and minimally invasive direct coronary bypass grafting (MIDCAB) are both well-accepted treatment options for isolated high-grade stenosis of proximal left anterior descending coronary artery. Small studies comparing the two modalities have yielded conflicting results. We performed a meta-analysis of randomized control trials to compare percutaneous intervention with minimally invasive coronary bypass grafting for isolated proximal left anterior descending artery stenosis. Five randomized trials with a total of 711 patients and average follow-up of 2.3 years were included in the analysis; 380 patients received stents and 331 underwent surgery. Only one trial used drug eluting stents. There were a small number of events overall in each trial. Difference between mortality was 12 events versus 15 between the PCI versus MIDCAB group. Similarly, the difference in myocardial infarction was 14 versus 10, and target vessel revascularization was 56 versus 19. The relative risk for stenting versus MIDCAB was 0.96 [(95% CI: 0.47, 1.99), p=0.92, I(2)=17.5%], for mortality and myocardial infarction, 0.77 [(95% CI: 0.30, 2.01), p=0.60, I(2)=10.4%] for mortality and 1.81 [(95% CI: 0.80, 4.06), p=0.15, I(2)=65.9%] for the composite end point of mortality, myocardial infarction and target vessel revascularization. Excluding the trial with drug eluting stents the relative risk for the composite outcome of mortality, myocardial infarction and target vessel revascularization was significantly higher for PCI [RR=2.27 (95% CI: 1.32, 3.90), p=0.003, I(2)=18.9%]. Overall mortality and myocardial infarction rates are similar for bare metal stents versus MIDCAB, but surgery was associated with significantly lower rates of repeat revascularization. The number of randomized patients and events were small. The effect of drug eluting stents might close the gap of repeat revascularization compared to MIDCAB for this disease.

Blood transfusion and in-hospital outcomes in anemic patients with myocardial infarction undergoing percutaneous coronary intervention.

Studies have shown poor prognostic implications of anemia in patients with myocardial infarction (MI) and in patients undergoing percutaneous coronary intervention (PCI). The impact of blood transfusion in these populations remains controversial. The objective of this study was to examine the effect of transfusion on in-hospital mortality in anemic patients undergoing PCI for MI. Data from 67,051 PCIs (June 1, 1997 to January 31, 2004) were prospectively collected in a multicenter registry (Blue Cross Blue Shield of Michigan Cardiovascular Consortium). Of these, 4,623 patients who were classified as anemic according to the World Health Organization criteria underwent PCI within 7 days of presentation with acute MI. A propensity score for being transfused was estimated for each patient, and propensity matching and a prediction model for in-hospital death were developed. The average age was 67.8 years, 57.7% of patients were men, and 22.3% of patients received a transfusion during hospitalization. Transfused patients, compared to nontransfused patients, were more likely to be older, female, have lower preprocedure hemoglobin levels, more comorbidities, and a higher unadjusted in-hospital mortality rate (14.52% vs. 3.01%, p < 0.0001). After adjustment for comorbidities and propensity for transfusion, blood transfusion was associated with a higher risk of in-hospital mortality (adjusted odds ratio = 2.02, 95% confidence interval 1.47-2.79, p < 0.0001). In anemic patients undergoing PCI for MI, transfusion was associated with an increased crude and adjusted rate of in-hospital mortality. A randomized controlled trial is needed to determine the value of transfusion and the ideal transfusion criteria.

Continuous aortic flow augmentation: a pilot study of hemodynamic and renal responses to a novel percutaneous intervention in decompensated heart failure.

BACKGROUND: Diminished aortic flow may induce adverse downstream vascular and renal signals. Investigations in a heart failure animal model have shown that continuous aortic flow augmentation (CAFA) achieves hemodynamic improvement and ventricular unloading, which suggests a novel therapeutic approach to patients with heart failure exacerbation that is inadequately responsive to medical therapy. METHODS AND RESULTS: We studied 24 patients (12 in Europe and 12 in the United States) with heart failure exacerbation and persistent hemodynamic derangement despite intravenous diuretic and inotropic and/or vasodilator treatment. CAFA (mean+/-SD 1.34+/-0.12 L/min) was achieved through percutaneous (n=19) or surgical (n=5) insertion of the Cancion system, which consists of inflow and outflow cannulas and a magnetically levitated and driven centrifugal pump. Hemodynamic improvement was observed within 1 hour. Systemic vascular resistance decreased from 1413+/-453 to 1136+/-381 dyne.s.cm(-5) at 72 hours (P=0.0008). Pulmonary capillary wedge pressure decreased from 28.5+/-4.9 to 19.8+/-7.0 mm Hg (P<0.0001), and cardiac index (excluding augmented aortic flow) increased from 1.97+/-0.44 to 2.27+/-0.43 L.min(-1).m(-2) (P=0.0013). Serum creatinine trended downward during treatment (overall P=0.095). There were 8 complications during treatment, 7 of which were self-limited. Hemodynamics remained improved 24 hours after CAFA discontinuation. CONCLUSIONS: In patients with heart failure and persistent hemodynamic derangement despite intravenous inotropic and/or vasodilator therapy, CAFA improved hemodynamics, with a reduction in serum creatinine. CAFA represents a promising, novel mode of treatment for patients who are inadequately responsive to medical therapy. The clinical impact of the observed hemodynamic improvement is currently being explored in a prospective, randomized, controlled trial.

Prognostic implication of anemia on in-hospital outcomes after percutaneous coronary intervention.

BACKGROUND: Although prior studies have shown a relationship between anemia and in-hospital mortality after coronary artery bypass grafting and acute myocardial infarction (MI), the prognostic implication of anemia in patients undergoing percutaneous coronary intervention (PCI) is unknown. Therefore, we evaluated the relationship between anemia and outcomes of PCI. METHODS AND RESULTS: Clinical and outcome data on 48,851 consecutive PCIs were prospectively collected. Patients were classified as anemic using the World Health Organization definition (<12.0 g/dL in women and <13.0 g/dL in men). A total of 6471 men (21.7%) and 4659 women (30.4%) were anemic. Anemic men and women were older and had a higher percentage of comorbidities compared with their nonanemic cohorts (P<0.0001 for all comparisons). When compared with nonanemic patients, anemic patients had higher in-hospital mortality (3.0% versus 0.8% in men; 2.4% versus 1.5% in women; P< or =0.0001) and postprocedural MI (2.0% versus 1.6% in men; 2.4% versus 1.6% in women; P< or =0.02) and a higher combined major cardiovascular events end point, including death, MI, and cerebrovascular event (5.0% versus 2.6% in men; 5.1% versus 3.5% in women; P<0.0001). After adjustment for comorbidities, anemia was associated with a higher risk of in-hospital mortality (odds ratio [OR], 2.29; 95% CI, 1.79 to 2.92; P<0.0001) and MI (OR, 1.34; 95% CI, 1.05 to 1.72; P=0.02) and major cardiovascular events (OR, 1.2; 95% CI, 1.05 to 1.34). Significant gender interactions were observed for death in men and for MI in women. CONCLUSIONS: Preprocedural anemia is associated with increased adverse in-hospital outcomes after PCI. Whether optimization of hemoglobin before PCI is of clinical benefit will need to be determined in a randomized clinical trial.

Statin therapy reduces contrast-induced nephropathy: an analysis of contemporary percutaneous interventions.

PURPOSE: We sought to examine whether statin therapy before percutaneous coronary intervention results in reduction in contrast-induced nephropathy (CIN). Intravascular administration of contrast media can have nephrotoxic effects, particularly in patients with baseline renal insufficiency. Along with lowering serum cholesterol, statins have pleiotropic effects in the vasculature. The effect of statin use on CIN is unknown. SUBJECTS AND METHODS: We studied 29409 patients who had both baseline preprocedure and peak postprocedure serum creatinine measured at the time of their percutaneous coronary intervention (PCI). Baseline demographics and creatinine profile before and after the procedure were compared between patients who received preprocedure statins and those who did not. CIN was defined as an increase in serum creatinine of < or =0.5 mg/dL. RESULTS: Baseline serum creatinine was similar between the two groups. When compared with patients who did not receive preprocedure statins, patients on preprocedure statins had a lower incidence of CIN (4.37 vs 5.93, P <0.0001) and nephropathy requiring dialysis (0.32 vs 0.49, P = 0.03). After adjustments for comorbidities, preprocedure statin use was associated with a significant reduction in CIN (odds ration [OR] 0.87, 95% confidence interval [CI] 0.77-0.99, P = 0.03). CONCLUSIONS: Preprocedure statin use is associated with significant reduction in CIN after contemporary PCI. This reinforces the need to initiate statin therapy before percutaneous coronary interventions.

Long-term outcomes based on time-to-angioplasty in patients admitted with non-ST-segment elevation acute coronary syndromes.

OBJECTIVE: We investigated the impact of the duration from hospital admission to coronary angiography on the outcome of patients admitted with non ST-segment elevation acute coronary syndromes (NSTE-ACS). BACKGROUND: Invasive risk stratification in patients with acute coronary syndromes (ACS) has been shown to improve outcome in contemporary studies. It is unclear whether early coronary angiography is better than initial medical therapy with later angiography. METHODS: We performed an analysis of patients admitted to a tertiary coronary intensive care unit (CICU) with NSTE-ACS and had coronary angiography performed during the same hospitalization. Patients were categorized into three groups based on the time-to-angiography: same-day, 1 to 2 days, and > 2 days. The baseline clinical features, angiography results, 30-day, 6-month cardiovascular outcome and 3-year mortality rate were compared between the groups before and after adjusting for confounding variables. RESULTS: A total of 836 fulfilled the inclusion criteria. Patients undergoing angiography > 2 days had a higher incidence of 3-vessel disease (45.7% vs. 31.7%, p < 0.001), underwent less percutaneous interventions at the time of the angiography (41.6% vs. 56.7%, p < 0.001), and more frequent coronary artery bypass surgery (9.9% vs. 15.3%, p = 0.05). Patients undergoing late invasive risk stratification (> 2 days) had increased 3-year mortality (OR 2.12, 95% CI 1.03-4.35, p = 0.04) after adjusting for confounding variables. CONCLUSION: In patients with NSTE-ACS and no contraindication to angiography, delayed angiography of more than 2 days of presentation was associated with increased mortality at 3 years.

Dyslipidemia in patients with angiographically confirmed coronary artery disease--an opportunity for improvement.

BACKGROUND: There are few data about lipid profiles in unselected patients with angiographically confirmed coronary artery disease (CAD). HYPOTHESIS: The study was undertaken to investigate the demographics, clinical characteristics, angiographic findings, and baseline lipid status of 1,000 consecutive unselected patients with angiographically confirmed CAD. METHODS: Between April 2001 and July 2002, we obtained informed consent and prospectively collected clinical characteristics, fasting lipid profiles, and angiographic results from 1,000 sequential patients with CAD confirmed by angiography. RESULTS: In these patients with confirmed CAD, 78% had history of hyperlipidemia. Although 62% were receiving lipid-lowering therapy, only 46% had a low-density lipoprotein target of < 100 mg/dl, and only 20% had achieved all four National Cholesterol Education Program-recommended lipid targets. CONCLUSIONS: Better strategies to ensure optimal lipid levels are required. One such method using computerized workflow is being evaluated in this population.

Do omega-3 polyunsaturated fatty acids reduce risk of sudden cardiac death and ventricular arrhythmias? A meta-analysis of randomized trials.

INTRODUCTION: Omega-3 polyunsaturated fatty acids (PUFA) have demonstrated to have antiarrhythmic properties. However, randomized studies have shown inconsistent results. OBJECTIVE: We aimed to analyze the effect of omega-3 PUFA on preventing potentially fatal ventricular arrhythmias and sudden cardiac death. METHODS: Randomized trials comparing omega-3 PUFA to placebo and reporting sudden cardiac death (SCD) or first implanted cardioverter-defibrillator (ICD) event for ventricular tachycardia or fibrillation were included in this study. A meta-analysis using a random effects model was performed and results were expressed in terms of Odds Ratio (OR) and 95% Confidence Interval (CI) after evaluating for interstudy heterogeneity using I(2). The reported data were extracted on the basis of the intention-to-treat principle. RESULTS: A total of 32,919 patients were included in nine trials; 16,465 patients received omega-3 PUFA and 16,454 received placebo. When comparing omega-3 PUFA to placebo, there was nonsignificant risk reduction of SCD or ventricular arrhythmias (OR = 0.82 [95% CI: 0.60-1.21], p = 0.21 I(2) = 49.7%). CONCLUSION: Dietary supplementation with omega-3 PUFA does not affect the risk of SCD or ventricular arrhythmias.

Low admission triglyceride and mortality in acute coronary syndrome patients.

BACKGROUND: The relationship between admission triglyceride (TG) levels and long-term outcomes has not been established in patients with acute coronary syndrome. We tested the hypothesis that patients who develop non-ST segment elevation myocardial infarction (NSTEMI) despite low TG have a worse cardiovascular outcome in the long term. METHODS: Patients admitted with NSTEMI between 1 January 1997 and 31 December 2000 and with fasting lipid profiles measured within 24 hours of admission were included for analysis. Baseline characteristics and three-year all-cause mortality were compared between the patients with TG above and below the median. Multivariate analysis was used to determine the predictors of all-cause mortality and adjusted survival was analyzed using the Cox proportional hazard model. RESULTS: Of 517 patients, 395 had TG £ 200 mg/dL and 124 had TG > 200 mg/dL. Patients with low TG were more often Caucasian, with no significant differences in gender or severity of coronary artery disease between the two groups. There was a trend for increased all-cause mortality at six months (9% vs 3%, p = 0.045) and three years (13.4% vs 5.6%, p = 0.016) in patients with low TG. In multivariate analysis, low TG level at admission was an independent predictor of increased mortality at three years (adjusted OR 2.5, 95% CI = 1.04-5.9, p = 0.04). CONCLUSIONS: In our cohort, lower TG at admission is associated with increased three-year mortality in patients with NSTEMI. Whether this is a result of current therapy, or a marker for worse baseline characteristics, needs to be studied further.

Low admission LDL-cholesterol is associated with increased 3-year all-cause mortality in patients with non ST segment elevation myocardial infarction.

BACKGROUND: The relationship between admission low-density lipoprotein (LDL) levels and long-term outcomes has not been established in patients with acute coronary syndrome. We tested the hypothesis that patients who develop non-ST segment elevation myocardial infarction (NSTEMI) despite low LDL have a worse cardiovascular outcome in the long term. METHODS: Patients admitted with NSTEMI between 1 January 1997 and 31 December 2000 and with fasting lipid profiles measured within 24 hours of admission were selected for analysis. Baseline characteristics and 3-year all-cause mortality were compared between the patients with LDL above and below the median. Multivariate analysis was used to determine the predictors of all-cause mortality, and adjusted survival was analyzed using the Cox proportional hazard model. RESULTS: Of the total of 517 patients, 264 had LDL 105 mg/dL. There was no difference in age, gender, severity of coronary artery disease, and left ventricular ejection fraction between the 2 groups. Thirty-six percent of patients with LDL 105 mg/dL were on lipid-lowering therapy on admission. After 3 years, patients with admission LDL 105 mg/dL (14.8% vs. 7.1%, p = 0.005). The higher all-cause mortality persisted (OR 1.8, 95% CI 1.0-3.5, p = 0.05) even after adjustment for confounding variables. CONCLUSIONS: In our cohort, lower LDL-cholesterol at admission was associated with decreased 3-year survival in patients with NSTEMI. Whether this was a result of current therapy or a marker for worse baseline characteristics needs to be studied further.

The recognition of acute coronary ischemia in the outpatient setting.

BACKGROUND: The missed diagnosis of acute myocardial infarction has been studied in the Emergency Department, but few studies have investigated how often coronary ischemia is correctly identified in the outpatient setting. METHODS: This was a single center retrospective observational study of patients with Health Alliance Plan medical insurance hospitalized at a US tertiary center with acute myocardial infarction in 2004. Outpatient encounters in the 30 days preceding acute myocardial infarction were reviewed by two independent cardiologists for presenting symptoms and diagnostic decision-making in order to classify patient presentations as acute coronary ischemia, stable angina or neither. RESULTS: There were 331 patients with acute myocardial infarction, including 190 (57%) with a primary diagnosis of AMI and evaluated by a physician in the preceding 30 days. This group included 68 patients with 95 documented outpatient encounters by a primary care physician, cardiologist, or other internal medicine specialist which formed the final study population. Mean interval between these encounters and AMI was 17 +/- 11 days. Of these patients, 7 (10%) had symptoms of acute coronary ischemia, 5 (7%) had stable angina symptoms, and 56 (83%) had no symptoms of coronary ischemia at their outpatient encounters. Of the 7 patients with acute coronary ischemic symptoms, 5 were correctly identified and 2 were misidentified. CONCLUSION: A majority of patients with subsequent AMI visit an outpatient provider in the month preceding AMI. However, few present with symptoms of coronary ischemia in the outpatient setting (10%) and these symptoms are not always identified as such.

Delay in invasive risk stratification of women with acute coronary syndrome is associated with worse outcomes.

BACKGROUND: Invasive risk stratification in patients with acute coronary syndromes (ACS) has been shown to improve outcomes. There is paucity of data on women undergoing invasive risk stratification. We investigated whether the time to coronary angiography affects survival of female patients admitted with ACS. METHOD: Female patients admitted to the coronary intensive care unit with ACS between 1/1/97 and 12/31/00 and undergoing coronary angiography during same hospitalization were divided into three groups based on the time to angiography: same day, 1-2 days and >2 days. The baseline clinical features, angiography results and outcomes were compared between the angiography groups. RESULTS: Of the total 350 female patients who fulfilled the inclusion criteria, 63% underwent angiography within two days of presentation. Three year mortality rates in women undergoing angiography on the same day, 1-2 days and >2-days were 7%, 7% and 22% respectively (p = 0.001). Using multivariate analysis, angiography beyond 2 days was a significant predictor of mortality among women (OR 2.6, 95% CI 1.3-5.0, p = 0.006) after adjusting for confounding variables. CONCLUSION: Later invasive risk stratification after 2 days of presentation in women with ACS is associated with worse survivial. Gender should not be a reason to defer early coronary angiography in these patients.

Prolongation of the QTc interval is seen uniformly during early transmural ischemia.

OBJECTIVES: In order to more clearly understand the electrocardiographic manifestations of early transmural ischemia, we studied electrocardiograms (ECGs) in patients undergoing balloon angioplasty. BACKGROUND: Decisions regarding reperfusion strategies in patients with acute myocardial infarction rely largely on the presence of ST-segment elevation (STE) in the ECG, consequently with significant limitations. Studies of the "ischemic cascade" show that ST-segment changes occur well after the onset of wall motion abnormalities. METHODS: We prospectively analyzed ECGs obtained at 20-s intervals in 74 patients undergoing elective balloon angioplasty. The ECGs were analyzed using 3 methodologies. In 74 patients, the ST-segment, the T-wave, and the QT-interval were analyzed using the MUSE (General Electric HC, Menomonee Falls, Wisconsin) automated system (MUSE). Fifty patients were also analyzed using the Interval Editor automated system (IE; General Electric HC). In 20 patients, measurements were made manually. RESULTS: Transmural ischemia prolonged the QTc interval (using the Bazett's formula) in 100% of patients. In all 74 patients analyzed with MUSE, QTc interval prolonged from 423 +/- 25 ms to 455 +/- 34 ms (p < 0.001). In the 50 patients analyzed with IE, QTc interval prolonged in 50 of 50 (100%) patients (from 424 +/- 27 ms to 458 +/- 33 ms [p < 0.001]). Mean time to maximal QTc interval prolongation, changes in T-wave polarity, > or =1 mm STE, and ST-segment depression (STD) were 22, 24, 29, and 35 s, respectively. Although QTc interval prolonged in 100% of patients, T-wave changes, STE, and STD (> or =1 mm) occurred in 7%, 15%, and 7%, respectively. CONCLUSIONS: The QTc interval prolongs in 100% of patients with early transmural ischemia. When compared with clinically accepted indexes of transmural ischemia (i.e., STD and STE [> or =1 mm]) it is the earliest ECG abnormality.