Showing papers by "Leslee J. Shaw published in 2013"

Body mass index and the prevalence, severity, and risk of coronary artery disease: an international multicentre study of 13 874 patients

Abstract: Aims Obesity is associated with the presence of coronary artery disease (CAD) risk factors and cardiovascular events. We examined the relationship between body mass index (BMI) and the presence, extent, severity, and risk of CAD in patients referred for coronary computed tomographic angiography (CCTA). Methods and results We evaluated 13 874 patients from a prospective, international, multicentre registry of individuals without known CAD undergoing CCTA. We compared risk factors, CAD findings, and risk of all-cause mortality and non-fatal myocardial infarction (MI) amongst individuals with underweight (18.5–20.0 kg/m2), normal (20.1–24.9 kg/m2), overweight (25–29.9 kg/m2), and obese (≥30 kg/m2) BMI. The mean follow-up was 2.4 ± 1.2 years with 143 deaths and 193 MIs. Among underweight, normal weight, overweight, and obese individuals, there was increasing prevalence of diabetes (7 vs.10% vs. 12 vs. 19%), hypertension (37 vs. 40% vs. 46 vs. 59%), and hyperlipidaemia (48 vs. 52% vs. 56 vs. 56%; P < 0.001 for trend). After multivariable adjustment, BMI was positively associated with the prevalence of any CAD [odds ratio (OR) 1.25 per +5 kg/m2, 95% confidence interval (CI): 1.20–1.30, P < 0.001] and obstructive (≥50% stenosis) CAD (OR: 1.13 per +5 kg/m2, 95% CI: 1.08–1.19, P < 0.001); a higher BMI was also associated with an increased number of segments with plaque (+0.26 segments per +5 kg/m2, 95% CI: 0.22–0.30, P < 0.001). Larger BMI categories were associated with an increase in all-cause mortality ( P = 0.004), but no difference in non-fatal MI. After multivariable adjustment, a higher BMI was independently associated with increased risk of MI (hazards ratio: 1.28 per +5 kg/m2, 95% CI: 1.12–1.45, P < 0.001). Conclusions Amongst patients with suspected CAD referred for CCTA, individuals with increased BMI have greater prevalence, extent, and severity of CAD that is not fully explained by the presence of traditional risk factors. A higher BMI is independently associated with increased risk of intermediate-term risk of myocardial infarction.

Impact of family history of coronary artery disease in young individuals (from the CONFIRM registry).

Abstract: Although family history (FH) of coronary artery disease (CAD) is considered a risk factor for future cardiovascular events, the prevalence, extent, severity, and prognosis of young patients with FH of CAD have been inadequately studied. From 27,125 consecutive patients who underwent coronary computed tomographic angiography, 6,308 young patients (men aged 50% stenosis in a coronary artery >2 mm diameter. Risk-adjusted logistic regression, Kaplan-Meier, and Cox proportional-hazards models were used to compare patients with and without FH of CAD. Compared with subjects without FH of CAD, those with FH of CAD (FH+) had higher prevalences of any CAD (40% vs 30%, p

Usefulness of Coronary Computed Tomography Angiography to Predict Mortality and Myocardial Infarction Among Caucasian, African and East Asian Ethnicities (from the CONFIRM [Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter] Registry)

Abstract: Studies examining coronary computed tomographic angiography (CCTA) have demonstrated increased mortality related to coronary artery disease (CAD) severity but are limited to relatively nondiverse ethnic populations. The aim of this study was to evaluate the prognostic significance of CAD on CCTA according to ethnicity for patients without previous CAD in a prospective international CCTA registry of 11 sites (7 countries) who underwent 64-slice CCTA from 2005 to 2010. CAD was defined as any coronary artery atherosclerosis and obstructive CAD as ≥50% stenosis. All-cause mortality and nonfatal myocardial infarction (MI) were assessed by ethnicity using Kaplan-Meier and Cox proportional hazards, controlling for baseline risk factors, medications, and revascularization. A total of 16,451 patients of mean age 58 years (55% men) were followed over a median of 2.0 years (interquartile range 1.4 to 3.2). Patients were 60.1% Caucasian, 34.4% East Asian, and 5.5% African. Death or MI occurred in 0.5% (38 of 7,109) among patients with no CAD, 1.6% (91 of 5,600) among those with nonobstructive CAD, and 3.8% (142 of 3,742) among those with ≥50% stenosis (p

Impact of Coronary Artery Calcium Progression and Statin Therapy on Clinical Outcome in Subjects With and Without Diabetes Mellitus

Abstract: Coronary artery calcium (CAC) is a marker of atherosclerosis, and CAC progression is independently associated with all-cause mortality in the general population but not convincingly in subjects with diabetes mellitus (DM). The aim of this study was to ascertain the differences in the rates of CAC progression, the effect of statin therapy, and all-cause mortality in subjects with and without DM. The study group consisted of 296 asymptomatic subjects with type 2 DM and 300 controls (mean age 59 ± 6 years, 29% women) who underwent baseline and follow-up CAC scans within a 2-year interval. Absolute annual CAC score change, percentage annual CAC progression(ΔCAC%), event-free survival, and the effect of statin therapy on survival were all assessed. The mean follow-up duration was 56 ± 11 months. Absolute annual CAC score change was 81 ± 10 in subjects with DM and 34 ± 5 in controls (p = 0.0001). Percentage annual CAC progression was 29 ± 9% in subjects with DM and 10 ± 7% in controls (p = 0.0001). The hazard ratios of death in 3 groups of subjects with DM compared to controls without DM were 1.88 (95% confidence interval [CI] 1.51 to 2.36, p = 0.0001) for ΔCAC of 10% to 20%, 2.29 (95% CI 1.56 to 3.38, p = 0.0001) for ΔCAC of 21% to 30%, and 6.95 (95% CI 2.23 to 11.53, p = 0.0001) for ΔCAC >30%, all compared to ΔCAC

Radiation safety in nuclear cardiology-current knowledge and practice: results from the 2011 American Society of Nuclear Cardiology member survey.

Abstract: N uclear stress testing is well recognized as an effective technique for diagnosing coronary disease, predicting patient outcomes, and guiding management. Numerous evidence-based appropriate indications and practice guideline recommendations have been published regarding accepted uses of nuclear stress tests (NSTs) across a wide spectrum of patients with known or suspected coronary disease. However, the approximate 10 million NSTs performed annually account for greater than 10% of the entire ionizing radiation burden to the US population. One recent study, while pointing out that cancer risk from a single NST is small, projected on a population level that NSTs may result in thousands of radiation-attributable cancers annually, partially offsetting their benefits.

Frequency, Predictors, and Consequences of Crossing Over to Revascularization Within 12 Months of Randomization to Optimal Medical Therapy in the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) Trial

Abstract: Background—In the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial, some patients with stable ischemic heart disease randomized to optimal medical therapy (OMT) crossed over to early revascularization. The predictors and outcomes of patients who crossed over from OMT to revascularization are unknown. Methods and Results—We compared characteristics of OMT patients who did and did not undergo revascularization within 12 months and created a Cox regression model to identify predictors of early revascularization. Patients’ health status was measured with the Seattle Angina Questionnaire. To quantify the potential consequences of initiating OMT without percutaneous coronary intervention, we compared the outcomes of crossover patients with a matched cohort randomized to immediate percutaneous coronary intervention. Among 1148 patients randomized to OMT, 185 (16.1%) underwent early revascularization. Patient characteristics independently associated with early revascula...

Cardiovascular risk among stable individuals suspected of having coronary artery disease with no modifiable risk factors: results from an international multicenter study of 5262 patients.

Abstract: Among stable individuals suspected of having coronary artery disease (CAD) without medically modifiable CAD risk factors, the presence of both nonobstructive and obstructive CAD is common and is associated with significantly higher risk of a major adverse cardiovascular event.

Left Ventricular Energy Model Predicts Adverse Events in Women With Suspected Myocardial Ischemia: Results From The NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study.

Abstract: Objectives: To assess the prognostic value of a left ventricular energy-model in women with suspected myocardial ischemia. Background: The prognostic value of internal energy utilization (IEU) of the left ventricle in women with suspected myocardial ischemia is unknown. Methods: Women [n=227, mean age 59±12 years (range, 31-86 years)], with symptoms of myocardial ischemia, underwent myocardial perfusion imaging (MPI) assessment for regional perfusion defects along with measurement of ventricular volumes separately by gated Single Photon Emission Computed Tomography (SPECT) (n=207) and magnetic resonance imaging (MRI) (n=203). During follow-up (40±17 months), time to first major adverse cardiovascular event (MACE, death, myocardial infarction or hospitalization for congestive heart failure) was analyzed using MRI and gated SPECT variables. Results: Adverse events occurred in 31 (14%). Multivariable Cox models were formed for each modality: IEU and wall thickness by MRI (Chi-squared 34, P<0.005) and IEU and systolic blood pressure by gated SEPCT (Chi-squared 34, P<0.005). The models remained predictive after adjustment for age, disease history and Framingham risk score. For each Cox model, patients were categorized as high-risk if the model hazard was positive and not high-risk otherwise. Kaplan-Meier analysis of time to MACE was performed for high-risk vs. not high-risk for MR (log rank 25.3, P<0.001) and gated SEPCT (log rank 18.2, P<0.001) models. Conclusions: Among women with suspected myocardial ischemia a high internal energy utilization has higher prognostic value than either a low EF or the presence of a myocardial perfusion defect assessed using two independent modalities of MR or gated SPECT.

Predictive Value of Cardiac Computed Tomography and the Impact of Renal Function on All Cause Mortality (from Coronary Computed Tomography Angiography Evaluation for Clinical Outcomes)

Abstract: Patients with chronic kidney disease have a worse cardiovascular prognosis than those without. The aim of this study was to determine the incremental prognostic value of coronary computed tomographic angiography in predicting mortality across the entire spectrum of renal function in patients with known or suspected coronary artery disease (CAD). A large international multicenter registry was queried, and patients with left ventricular ejection fraction (LVEF) and creatinine data were screened. National Cholesterol Education Program Adult Treatment Panel III risk was calculated. Coronary computed tomographic angiographic results were evaluated for CAD severity (normal, nonobstructive, or obstructive) and an LVEF <50%. Patients were followed for the end point of all-cause mortality. Among 5,655 patients meeting the study criteria, follow-up was available for 5,572 (98.9%; median follow-up duration 18.6 months). All-cause mortality (66 deaths) significantly increased with every 10-unit decrease in renal function (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.07 to 1.41). All-cause mortality occurred in 0.33% of patients without coronary atherosclerosis, 1.82% of patients with nonobstructive CAD, and 2.43% of patients with obstructive CAD. Multivariate Cox proportional-hazards models revealed that impaired renal function (HR 2.29, 95% CI 1.65 to 3.18), CAD severity (HR 1.81, 95% CI 1.31 to 2.51), and an abnormal LVEF (HR 4.16, 95% CI 2.45 to 7.08) were independent predictors of all-cause mortality. In conclusion, coronary computed tomographic angiographic measures of CAD severity and the LVEF provide effective risk stratification across a wide spectrum of renal function. Furthermore, renal dysfunction, CAD severity, and the LVEF have additive value for predicting all-cause death in patients with suspected obstructive CAD.

Risk Stratification and Patient Management

Abstract: Since its beginnings in the early 1970s, clinical nuclear cardiology has evolved substantially, gaining both technical sophistication and enhanced imaging capabilities. Importantly, in parallel to these developments, an extensive literature supporting the clinical and cost-effectiveness of this modality has developed. Today, state-of-the-art nuclear cardiology allows for the objective measurement of both myocardial function and relative regional myocardial perfusion at rest and stress, providing accurate risk assessment in a wider variety of patient subsets. This chapter will highlight stress myocardial perfusion single-photon emission CT (SPECT), which currently comprises approximately 95 % of the procedures performed in this field.

Improved diagnosis and prognosis using Decisions Informed by Combining Entities (DICE): results from the NHLBI-sponsored Women's Ischemia Syndrome Evaluation (WISE).

Abstract: Objectives: To introduce an algorithmic approach to improve the interpretation of myocardial perfusion images in women with suspected myocardial ischemia. Background: Gated single photon emission computed tomography (SPECT) and magnetic resonance (MR) myocardial perfusion imaging (MPI) approaches have relatively poor diagnostic and prognostic value in women with suspected myocardial ischemia. Here we introduce an approach: Decisions Informed by Combining Entities (DICE) that forms a mathematical model utilizing MPI and cardiac dimensions generated by one modality to predict the perfusion status of another modality. The effect of the model is to systematically incorporate cardiac metrics that influence the interpretation of perfusion images, leading to greater consistency in designation of myocardial perfusion status between studies. Methods: Women (n=213), with suspected myocardial ischemia, underwent MPI assessment for regional perfusion defects using two modalities: gated SPECT (n=207) and MR imaging (n=203). To determine perfusion status, MR data were evaluated qualitatively and semi-quantitatively while SPECT data were evaluated using conventional clinical criteria. These perfusion status readings were designated “Original”. Four regression models were generated to model perfusion status obtained with one modality [e.g., semi-quantitative magnetic resonance imaging (MRI)] against another modality (e.g., SPECT) and a threshold applied (DICE modeling) to designate perfusion status as normal or low. The DICE models included perfusion status, left ventricular (LV) chamber volumes and myocardial wall thickness. Women were followed for 40±16 months for the development of first major adverse cardiovascular event (MACE: CV death, nonfatal myocardial infarction (MI) or hospitalization for congestive heart failure). Original and DICE perfusion status were compared in their ability to detect high-grade coronary artery disease (CAD) and for prediction of MACE. Results: Adverse events occurred in 25 (12%) women and CAD was present in 34 (16%). In receiveroperator characteristic (ROC) analysis for CAD detection, the average area under the curve (AUC) for DICE vs. Original status was 0.77±0.03 vs. 0.70±0.03, P<0.01. Similarly, in Kaplan-Meier survival analysis the average log-rank statistic was higher for DICE vs. the Original readings (10.6±5.2 vs. 3.0±0.6, P<0.05). Conclusions: While two data sets are required to generate the DICE models no knowledge of follow-up results is needed. DICE modeling improved diagnostic and prognostic value vs. the Original interpretation of the myocardial perfusion status.

Healthcare Costs of Angina in Women

Abstract: This chapter examines the data on costs of cardiovascular care for women and highlights the importance of chest pain and the burden of persistent angina as driving higher costs of care. For women, a consistent body of evidence reports that women (generally) utilize more healthcare resources than men. A large component of the costs of care includes those for ongoing symptoms including the burden of angina. Within the NIH-NHLBI Women’s Ischemia Syndrome Evaluation (WISE) study, costs of care were estimated for symptomatic women with and without obstructive coronary artery disease. Even women with none to mild non-obstructive coronary artery disease had predicted lifetime costs of cardiovascular care of approximately 750,000 US dollars and this amount increased for women with coronary artery disease. The economic burden of angina, even in the setting of nonobstructive CAD, is costly and can result in high lifetime costs of care. Physicians should consider the intensity of resources required to adequately care for women with angina including the financial burden of family household resources.

Anatomy trumps all

Abstract: In this issue of iJACC , Pontone et al. [(1)][1] present an intriguing report on the comparative prognostic accuracy of exercise electrocardiography (ECG) as compared with coronary computed tomographic angiography (CTA) findings. Several important factors are noteworthy. First, the population is

Cardiac Syndrome X Prognosis

Abstract: While historically Cardiac Syndrome X (CSX), characterized by the triad of chest pain, abnormal stress testing and no obstructive coronary artery disease (CAD), has been believed to have a benign prognosis, newer data documents otherwise. Multiple findings in larger, better characterized populations with longer follow-up time periods document a relatively high risk for major adverse cardiac events in those subjects with mechanisms related to microvascular coronary dysfunction (MCD) and manifestations of ischemia. Specifically, CSX related to MCD has an adverse prognosis and health care cost expenditure comparable to obstructive CAD in both stable angina and unstable acute coronary syndrome patient populations. Invasive assessment of coronary reactivity testing, including endothelial and non-endothelial pathway testing provides potent prognostic information in subject with normal and minimal diseased coronary arteries. Additional assessment by non-invasively determined coronary or myocardial blood flow reserve provides additive prognostic value to routine coronary angiography. The presence of persistent chest pain alone at 1 year following index coronary angiography predicts an adverse prognosis. MCD predicts a relatively greater proportion of heart failure events compared to myocardial infarction, suggesting potential links between MCD and heart failure with preserved systolic function, although longer term follow-up of ventricular function has not been performed. The high prevalence of this condition, adverse prognosis and substantial health care costs particularly in women, coupled with the lack of evidence-base regarding treatment places intervention trials in this patient population as a research priority area.