Citations 288

Intracardiac Thrombosis and Embolism in Patients With Cardiac Amyloidosis

Circulation | November 6, 2007 | Volume: 116 | Issue: 21 | Pages: 2420-2426

10.1161/circulationaha.107.697763 | PMID 17984380

Background— Patients with primary amyloidosis (AL type) have a poor prognosis, in part due to frequent cardiac involvement. Although intracardiac thrombus has been reported in anecdotal cases, neither its frequency nor its role in causing mortality is known. Furthermore, the clinical and echocardiographic variables that may be associated with thromboembolism in cardiac amyloidosis have not been defined. Methods and Results— A total of 116 autopsy or explanted cases of cardiac amyloidosis (55 AL and 61 other type) were identified in the Mayo Clinic. Forty-six fatal nonamyloid trauma cases served as controls. Each heart was examined for intracardiac thrombus. The cause of death was determined from autopsy and clinical notes. Intracardiac thrombosis was identified in 38 hearts (33%). Twenty-three had 1 thrombus, whereas 15 had 2 to 5 thrombi. Although subjects in the AL group were younger and had less atrial fibrillation than those with other types of amyloidosis, the AL group had significantly more intracardiac thrombus (51% versus 16%, P <0.001) and more fatal embolic events (26% versus 8%, P <0.03). Control hearts had no intracardiac thrombus. The presence of both atrial fibrillation and AL was associated with an extremely high risk for thromboembolism (odds ratio 55.0 [95% confidence interval 8.1 to 1131.4]). By multivariate analysis, AL type (odds ratio 8.4 [95% confidence interval 1.8 to 51.2]) and left ventricular diastolic dysfunction (odds ratio 12.2 [95% confidence interval 2.7 to 72.7]) were independently associated with thromboembolism. Conclusions— A high frequency of intracardiac thrombosis was present in cardiac amyloidosis. Furthermore, thromboembolism caused significant fatality. Several risk factors for thromboembolism were identified. Early screening, especially in high-risk patients, and early anticoagulation might reduce morbidity and mortality.
Risk Stratification for Heart Failure and Death in an Acute Coronary Syndrome Population Using Inflammatory Cytokines and N-Terminal Pro-Brain Natriuretic Peptide

Clinical Chemistry | October 11, 2007 | Volume: 53 | Issue: 12 | Pages: 2112-2118

10.1373/clinchem.2007.090613 | PMID 17932131

Abstract Background: Inflammation in acute coronary syndrome (ACS) can identify those at greater long-term risks for heart failure (HF) and death. The present study assessed the performance of interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 (MCP-1) (cytokines involved in the activation and recruitment of leukocytes) in addition to known biomarkers [e.g., N-terminal pro-brain natriuretic peptide (NT-proBNP)] for predicting HF and death in an ACS population. Methods: In a cohort of 216 ACS patients, NT-proBNP (Elecsys®; Roche) and IL-6, IL-8, and MCP-1 (evidence investigator™; Randox) were measured in serial specimens collected early after symptom onset (n = 723). We collected at least 2 specimens from each participant: an early specimen (median 2 h; interquartile range 2–4 h) and a later specimen (9 h; 9–9 h), and used the later specimens’ biomarker concentrations for risk stratification. Results: An increase in both IL-6 and NT-proBNP was observed but not for IL-8 or MCP-1 early after pain onset. Kaplan–Meier analysis demonstrated that individuals with increased NT-proBNP (&gt;183 ng/L) or cytokines (IL-6 &gt; 6.4 ng/L; above upper limit of normal for IL-8 or MCP-1) had a greater probability of death or HF in the following 8 years (P &lt;0.05). In a Cox proportional hazard model adjusted for both CRP and troponin I, increased IL-6, MCP-1, and NT-proBNP remained significant risk factors. Combining all 3 biomarkers resulted in a higher likelihood ratio for death or HF than models restricted to any 2 of these biomarkers. Conclusion: IL-6, MCP-1, and NT-proBNP are independent predictors of long-term risk of death or HF, highlighting the importance of identifying leukocyte activation and recruitment in ACS patients.
Regional Systems of Care to Optimize Timeliness of Reperfusion Therapy for ST-Elevation Myocardial Infarction

Circulation | August 2, 2007 | Volume: 116 | Issue: 7 | Pages: 729-736

10.1161/circulationaha.107.699934 | PMID 17673456

Background— Quality improvement efforts have focused on strategies to improve the timeliness of reperfusion therapy in ST-elevation myocardial infarction patients who present to hospitals with and without percutaneous coronary intervention (PCI) capability. We implemented and evaluated a protocol to optimize the timeliness of reperfusion therapy and to coordinate systems of care for a PCI center and 28 regional hospitals located up to 150 miles away across 3 states. Methods and Results— The present study focused on a prospective, observational cohort of 597 patients who presented with ST-segment elevation and within 12 hours of symptom onset to Saint Marys Hospital and 28 regional hospitals up to 150 miles away between May 2004 and December 2006. The Mayo Clinic ST-elevation myocardial infarction protocol implemented strategies to improve timeliness of reperfusion therapy and to coordinate systems of care for transfer between hospitals. The study sample consisted of 258 patients who presented to Saint Marys Hospital and were treated with primary PCI (group A), 105 patients who presented to a regional hospital with symptom onset >3 hours and then were transferred for primary PCI (group B), and 131 patients who presented to a regional hospital with symptom onset <3 hours and were treated with full-dose fibrinolytic therapy (group C). For groups A and B, median door-to-balloon times were 71 and 116 minutes, respectively. Door-to-balloon time <90 minutes was achieved in 75% of group A and 12% of group B. Median door-to-needle time was 25 minutes for group C, and 70% had door-to-needle time <30 minutes. Conclusions— The Mayo Clinic ST-elevation myocardial infarction protocol demonstrates the feasibility of implementing strategies to optimize the timeliness of reperfusion therapy and the times that can be achieved through coordinated systems of care for ST-elevation myocardial infarction patients presenting to a PCI center (Saint Marys Hospital) and 28 regional hospitals without PCI capability located up to 150 miles away across 3 states.
Serial Biomarker Measurements in Ambulatory Patients With Chronic Heart Failure

Circulation | June 26, 2007 | Volume: 116 | Issue: 3 | Pages: 249-257

10.1161/circulationaha.107.694562 | PMID 17592074

Background— Cardiac troponin T (cTnT) and B-type natriuretic peptide (BNP) have been used to estimate prognosis in heart failure; however, most studies have evaluated decompensated patients with single measurements. To determine if there are advantages to serial measurements, we evaluated stable chronic heart failure patients every 3 months for 2 years. Methods and Results— A cohort of 190 New York Heart Association class III–IV heart failure patients was prospectively enrolled from June 2001 to January 2004. Primary end points were death, cardiac transplantation, or hospitalization. At study enrollment cTnT was <0.01 ng/mL in 87 (45.8%) patients, 0.01 to 0.03 ng/mL in 50 (26.3%) patients, and >0.03 ng/mL in 53 (27.9%) patients. An increase in cTnT above normal (<0.01 ng/mL) carried a 3.4-fold increased risk ( P =0.019). Further increases (≥20%) from an elevated level worsened the overall risk (hazard ratio, 5.09; P <0.001). BNP was elevated (>95th percentile for age and gender normal population) in 122 (64.2%) patients. An elevation of BNP from normal at any time during the study was associated with a poor outcome, but, once elevated, further changes in BNP (increases or decreases) remained associated with the same risk (hazard ratio, 5.09; P <0.001). Combined elevations of cTnT (>0.03 ng/mL) and BNP defined the highest risk group (hazard ratio, 8.58; P <0.001). Conclusions— Elevations of cTnT or BNP from normal detected at any time during clinical follow-up in ambulatory patients with chronic heart failure are highly associated with an increased risk of events. Further increases in cTnT contribute to additional risk. Combined elevations of cTnT and BNP contribute the highest risk. The ability to monitor changes by serial measurements adds substantially to the assessment of risk in this patient population.
Myocardial Infarction with Normal Coronary Arteries: A Role for MRI?

Clinical Chemistry | April 27, 2007 | Volume: 53 | Issue: 5 | Pages: 995-996

10.1373/clinchem.2007.086199 | PMID 17468413

Long-Term Health Outcomes Associated with Detectable Troponin I Concentrations

Clinical Chemistry | January 5, 2007 | Volume: 53 | Issue: 2 | Pages: 220-227

10.1373/clinchem.2006.076885 | PMID 17204519

Abstract Background: Recent data suggest that older men with detectable cardiac troponin I (cTnI) concentrations that remain below the 99th percentile concentration cutoff are at increased risk for subsequent cardiovascular events. We designed this study to extend this observation by examining risk prediction in both men and women presenting to an emergency department with chest discomfort. Methods: We obtained data for all-cause mortality and hospital discharges associated with either acute myocardial infarction (AMI) or congestive heart failure (CHF) for up to 8 years after the initial presentation in 448 patients who originally presented in 1996 with acute coronary syndrome (ACS). We performed retrospective analysis for cTnI (AccuTnI™; Beckman Coulter) in frozen plasma samples based on the patients’ reported time from onset of symptoms. Peak cTnI concentration was used for risk assessment. Results: Patients with cTnI concentrations ≥0.02 μg/L (i.e., limit of detection), including those whose peak values remained below the 99th percentile (0.04 μg/L), were at greater risk for death and AMI/CHF readmissions at 2, 5, and 8 years of follow-up compared with those with peak cTnI &lt;0.02 μg/L. All results were statistically significant (P &lt;0.05) except for death within 2 years among patients with normal but detectable cTnI (0.02 to 0.03 μg/L), relative to the group with values &lt;0.02 μg/L. Kaplan–Meier analyses indicated that both men and women with cTnI ≥0.02 μg/L had worse outcomes (P &lt;0.001). Conclusion: Both men and women who present with possible ACS with detectable cTnI concentrations that remain below the 99th percentile are at a greater risk for future adverse events.
Health Outcomes Categorized by Current and Previous Definitions of Acute Myocardial Infarction in an Unselected Cohort of Troponin-Naïve Emergency Department Patients

Clinical Chemistry | September 21, 2006 | Volume: 52 | Issue: 11 | Pages: 2028-2035

10.1373/clinchem.2006.073403 | PMID 16990413

Abstract Background: In a population originally classified for acute myocardial infarction (AMI) by the World Health Organization (WHO) definition, we compared the health outcomes after retrospectively reclassifying with the European Society of Cardiology and the American College of Cardiology (ESC/ACC) AMI definition, using the peak cardiac troponin I (cTnI) concentrations. The health outcomes were based on the WHO definition and occurred in an era that preceded the use of cardiac troponin biomarkers. Methods: For 448 patients who presented to the emergency department with symptoms suggestive of cardiac ischemia in 1996, we obtained data for all-cause mortality and recurrent AMI for up to 1 year after the initial presentation. We performed retrospective analysis of the patients’ frozen plasma samples to measure cTnI (AccuTnI®, Beckman Coulter). Results: At 30, 120, and 360 days, the risk for AMI/death in patients positive for AMI by only the ESC/ACC criteria was significantly lower than the risk in patients positive by both ESC/ACC and WHO criteria, and significantly higher than in patients negative according to both criteria. In a separate analysis, patients with a peak cTnI &gt;0.10 μg/L were at greater risk for AMI/death than patients with cTnI concentrations of 0.04–0.10 μg/L. Patients negative by both definitions or with peak cTnI concentrations &lt;0.04 μg/L had the highest event-free survival rates (92% and 94%, respectively) at 1 year. Conclusion: In a troponin-naïve population, patients classified as positive for AMI by only the ESC/ACC criteria have a prognosis that appears to be intermediate between those classified positive by both the WHO and ESC/ACC definitions and those who meet neither criteria.
Redefinition of Myocardial Infarction

Circulation | August 15, 2006 | Volume: 114 | Issue: 8 | Pages: 790-797

10.1161/circulationaha.106.627505 | PMID 16908764

Background— The 2000 European Society of Cardiology/American College of Cardiology definition for myocardial infarction (MI) combines ischemic symptoms, electrocardiographic changes, and troponin rather than creatine kinase levels. The use of troponins will increase the detection of MI by a magnitude to be quantified, and the clinical acceptance of the new definition is unknown. Method and Results— Subjects presenting to an Olmsted County facility with a troponin T value ≥0.03 ng/mL between November 2002 and March 2005 were prospectively classified through the use of standardized MI criteria, relying on cardiac pain, Minnesota coding of the ECG, and troponin, creatine kinase, and its MB fraction measured simultaneously. Through the use of dynamic changes in troponin, 538 MIs were identified versus 327 with creatine kinase and 427 with only the MB fraction of creatine kinase. This represents a 74% (95% confidence interval [CI], 69% to 79%) increase above the number of MIs identified with creatine kinase and a 41% (95% CI, 37% to 46%) increase above the number identified with criteria including only its MB fraction. When relying on single values of troponin, increases in the number of MIs were always large but varied widely according to the threshold used for troponin. Cases meeting only troponin-based criteria were less likely to have electrocardiographic ST-segment elevation and had better survival than those identified with previous criteria. Clinician diagnoses mentioned MI in 42% (95% CI, 34% to 49%) of cases meeting only troponin-based criteria versus 74% (95% CI, 69% to 78%) for MIs meeting the previous criteria ( P <0.001). Conclusions— The prospective application of the new criteria in the community results in a large increase in the number of MIs and a change in case mix. The clinical acceptance of the new criteria is incomplete, and studies that rely exclusively on dismissal diagnoses to assess MI rates may underestimate the burden of disease as presently defined.
Lipoprotein-Associated Phospholipase A 2 and Prognosis After Myocardial Infarction in the Community

Arteriosclerosis, Thrombosis, and Vascular Biology | August 11, 2006 | Volume: 26 | Issue: 11 | Pages: 2517-2522

10.1161/01.atv.0000240406.89440.0c | PMID 16902161

Objective— We evaluated the role of lipoprotein-associated phospholipase A 2 (Lp-PLA 2 ), an inflammatory biomarker, in defining risk after myocardial infarction (MI). Methods and Results— Olmsted County, Minn, residents who experienced an MI meeting standardized criteria between 2003 and 2005 (n=271) were prospectively identified and followed. Lp-PLA 2 levels were measured at baseline and evaluated along with traditional risk indicators. Lp-PLA 2 was modestly associated with total and low-density lipoprotein cholesterol, smoking, and age (inversely) but not with MI characteristics or severity, comorbidities, C-reactive protein, or the time from symptom onset to blood sampling. During the first year of follow-up, 42 deaths occurred. The survival estimates (95% confidence intervals [CI]) at 1 year were 92% (86% to 98%), 85% (78% to 93%), and 74% (65% to 84%) in the lowest, middle, and upper Lp-PLA 2 tertiles, respectively ( P =0.007). After adjustment for age and sex, the hazard ratios for death in the middle and upper Lp-PLA 2 tertiles were 2.20 (95% CI: 0.88 to 5.54) and 4.93 (95% CI: 2.10 to 11.60), compared with the lowest tertile, respectively ( P trend <0.001). Further adjustment for other risk indicators resulted in even stronger associations. Lp-PLA 2 also contributed to risk discrimination as indicated by the increases in the area under the receiver operating characteristic curves obtained in each of the models examined (all P ≤0.05). Conclusions— Among community subjects presenting with MI, increased Lp-PLA 2 levels measured early after MI are strongly and independently associated with mortality and provide incremental value in risk discrimination over traditional predictors.
Letter Regarding Article by Khan et al, “Prognostic Value of Troponin T and I Among Asymptomatic Patients With End-Stage Renal Disease: A Meta-Analysis”

Circulation | May 22, 2006 | Volume: 113 | Issue: 20 | Pages: No page available

10.1161/circulationaha.105.607341 | PMID 16717158