Perfusion Abnormality, Normal Coronaries, and Chest Pain⁎⁎Editorials published in the Journal of the American College of Cardiology reflect the views of the authors and do not necessarily represent the views of JACC or the American College of Cardiology

Coronary artery disease and its risk factors in patients presenting for liver transplantation

STUDY OBJECTIVE

To determine the distribution of coronary artery disease (CAD) and its risk factors across the various etiologies of end-stage liver disease, and to elucidate the relationship between severe alcohol consumption and CAD.

DESIGN

Retrospective multicenter study analysis.

SETTING

National Standard Transplant Analysis and Research file data.

MEASUREMENTS

Data from all primary adult orthotopic liver transplant recipients during the period from 2004 through 2006 were studied. Data were divided into 5 groups according to each patient's etiology of end-stage liver disease. The prevalence of CAD and the distribution of its risk factors were compared among groups.

MAIN RESULTS

17,482 cases were studied. The incidence of CAD was highest in nonalcoholic hepatic steatosis (7.4%) and lowest in biliary cirrhosis (1.7%). No difference in prevalence of CAD and its risk factors was noted between the viral and alcoholic etiologies (Hepatitis C 2.7%, Hepatitis B 2.3%, and alcoholic cirrhosis 2.9%).

CONCLUSIONS

Prevalence of CAD and the distribution of CAD risk factors in patients with severe alcohol consumption were similar to patients with viral hepatitis. CAD was most prevalent in patients with hepatic steatosis. This study argues against the notion of decreased expression and progression of CAD in patients with alcoholic cirrhosis presenting for liver transplantation.

Reproducibility of myocardial perfusion reserve - variations in measurements from post processing using commercially available software

PURPOSE

Adenosine stress first pass cardiac magnetic resonance imaging (CMRI) is a rapidly evolving tool in the diagnosis of ischemic heart disease (IHD). The rest and stress first pass myocardial perfusion data may be interpreted using commercially available software for calculation of time intensity curves in order to generate a numeric value of the segmental or whole heart myocardial perfusion reserve index (MPRI). The objective of this study was to determine the inter- and intra-observer reliability of the data generated by standard commercially available software.

METHODS

Data from 20 adenosine stress CMRI (1.5 T) studies were analyzed using commercially available CAAS MRV 3.3 software (Pie Medical Imaging B.V., Netherlands) for calculation of the MPRI. The stress CMRI was performed using a standardized protocol in 20 women including 10 women with angina and the absence of obstructive CAD and 10 healthy volunteers. MPRI calculation was made in a standardized manner on separate occasions by two independent observers. A single observer repeated the calculation of MPRI three months later, without reference to the prior data. Basal, mid, and apical segments, for the whole myocardium, sub-endocardium, and sub-epicardium were analyzed. Intra-class correlation coefficients (ICC), repeatability coefficients (RC), and coefficients of variation (CoV) were determined.

RESULTS

The MPRI results by repeated software measurements were highly correlated, with potentially important variations in measurement observed. The myocardial inter-observer ICC was 0.80 (95% CI, 0.57, 0.92) with a CoV of 7.5%, and intra-observer ICC was 0.89 (95% CI, 0.77, 0.95) with a CoV of 3.6%. The mid-ventricular level MPRI was most reproducible, with intra-observer ICC at 0.91 (95% CI, 0.77, 0.97); intra-observer measurement was more reproducible than inter-observer measurement.

CONCLUSIONS

There is variation in measurement of MPRI observed in post processing of perfusion data when using a standardized approach and commercially available software. This has implications in the interpretation of data obtained for clinical and research purposes.

Myocardial ischemia in the absence of obstructive coronary artery disease in systemic lupus erythematosus

OBJECTIVES

the purpose of this study was to evaluate the presence of myocardial ischemia measured by adenosine stress cardiac magnetic resonance (CMR) using visual myocardial perfusion and a quantitative myocardial perfusion reserve index (MPRI) in the absence of obstructive coronary artery disease (CAD) in women with systemic lupus erythematosus (SLE) with anginal chest pain (CP).

BACKGROUND

ischemic heart disease is a leading cause of morbidity and mortality in SLE. Previous studies demonstrated the presence of perfusion defects using adenosine stress CMR in patients with CP and no obstructive CAD, consistent with microvascular coronary dysfunction in patients without SLE.

METHOD

Twenty female SLE patients with typical and atypical anginal CP were prospectively enrolled. Patients with established cardiovascular disease were excluded. CMR was performed with 0.05 mmol/kg gadolinium adenosine stress first-pass perfusion in SLE patients and in 10 asymptomatic reference control women. SLE patients also underwent 64-slice coronary computed tomography angiography. CMR was scored visually and quantitatively (MPRI).

RESULTS

among 18 patients with complete data, no patient had obstructive CAD; however, 8 of 18 (44%) displayed visual perfusion defects on stress CMR compared with 0 in 10 control subjects (p = 0.014). The mean MPRI in patients versus controls was 2.0 ± 0.4 versus 2.4 ± 0.4 (p = 0.031) in the subepicardium and 1.8 ± 0.3 versus 2.1 ± 0.4 (p = 0.24) in the subendocardium. Multivariate linear regression revealed that SLE was the only predictor of subepicardial (p < 0.0025; β = -1.059) and subendocardial (p < 0.05; β = -0.529) MPRIs.

CONCLUSIONS

we observed a 44% prevalence of abnormal stress myocardial perfusion by CMR in the absence of obstructive CAD in SLE patients with anginal CP. Compared with controls, reduced MPRI was observed in SLE patients, and SLE presence was a significant predictor of an abnormal MPRI. These findings are consistent with the hypothesis that anginal CP in SLE patients without obstructive CAD is due to myocardial ischemia potentially caused by microvascular coronary dysfunction. Further research in a larger SLE population is warranted.

The relationship between early left ventricular myocardial alterations and reduced coronary flow reserve in non-insulin-dependent diabetic patients with microvascular angina

AIMS

To evaluate left ventricular (LV) systolic and diastolic myocardial function, and their relation to coronary flow reserve in patients with non-insulin-dependent diabetes mellitus (DM) and microvascular angina.

METHODS AND RESULTS

We selected a population of 45 normotensive patients with DM (56.3 ± 8.2 years; 25 males) with LV ejection fraction >50% and microvascular angina (anginal pain, positive imaging stress test and normal coronary angiography). Thirty-five age- and sex-matched healthy controls were also enrolled. All the patients underwent standard echocardiography, Tissue Doppler (TDI), two-dimensional strain (2DSE) imaging, and coronary flow reserve (CFR) measurement. LV myocardial early diastolic peak velocities (E(m)) and peak systolic 2DSE were reduced in both interventricular septum (IVS) and LV lateral wall (p<0.01) in DM, as well as CFR (1.89 ± 0.7 vs 2.55 ± 0.56, p<0.0001) compared with controls. By multivariate analysis, the independent determinants of E(m) were glycated haemoglobin (β coefficient=-0.36; p<0.01) and age (β=-0.46, p<0.001), while global longitudinal strain was predicted by glycated haemoglobin (β=0.48, P<0.001) and by the duration of the disease (β=0.38, P<0.005). An independent association between LV global longitudinal strain and CFR (β coefficient=-0.47, p<0.001) in DM patients was also evidenced.

CONCLUSIONS

TDI, 2DSE and CFR are valuable non-invasive and easy-repeatable tools for detecting LV myocardial and coronary function in DM patients with microvascular angina.

Prognostic value of global MR myocardial perfusion imaging in women with suspected myocardial ischemia and no obstructive coronary disease: results from the NHLBI-sponsored WISE (Women's Ischemia Syndrome Evaluation) study

OBJECTIVES

The purpose of this study was to assess the prognostic value of global magnetic resonance (MR) myocardial perfusion imaging (MPI) in women with suspected myocardial ischemia and no obstructive (stenosis <50%) coronary artery disease (CAD).

BACKGROUND

The prognostic value of global MR-MPI in women without obstructive CAD remains unknown.

METHODS

Women (n = 100, mean age 57 ± 11 years, age range 31 to 76 years), with symptoms of myocardial ischemia and with no obstructive CAD, as assessed by coronary angiography, underwent MR-MPI and standard functional assessment. During follow-up (34 ± 16 months), time to first adverse event (death, myocardial infarction, or hospitalization for worsening anginal symptoms) was analyzed using global MPI and left ventricular ejection fraction (EF) data.

RESULTS

Adverse events occurred in 23 (23%) women. Using univariable Cox proportional hazards regression modeling, variables found to be predictive of adverse events were global MR-MPI average uptake slope (p < 0.05), the ratio of MR-MPI peak signal amplitude to uptake slope (p < 0.05), and EF (p < 0.05). Two multivariable Cox models were formed, 1 using variables that were performance site dependent: ratio of MR-MPI peak amplitude to uptake slope together with EF (chi square: 13, p < 0.005); and a model using variables that were performance site independent: MR-MPI slope and EF (chi square: 12, p < 0.005). Each of the 2 multivariable models remained predictive of adverse events after adjustment for age, disease history, and Framingham risk score. For each of the Cox models, patients were categorized as high risk if they were in the upper quartile of the model and as not high risk otherwise. Kaplan-Meier analysis of time to event was performed for high risk versus not high risk for site-dependent (log rank: 15.2, p < 0.001) and site-independent (log rank: 13.0, p < 001) models.

CONCLUSIONS

Among women with suspected myocardial ischemia and no obstructive CAD, MR-MPI-determined global measurements of normalized uptake slope and peak signal uptake, together with global functional assessment of EF, appear to predict prognosis.

Coronary microvascular reactivity to adenosine predicts adverse outcome in women evaluated for suspected ischemia results from the National Heart, Lung and Blood Institute WISE (Women's Ischemia Syndrome Evaluation) study

OBJECTIVES

We investigated whether coronary microvascular dysfunction predicts major adverse outcomes during follow-up among women with signs and symptoms of ischemia.

BACKGROUND

Altered coronary reactivity occurs frequently in women evaluated for suspected ischemia, and the endothelium-dependent component is linked with adverse outcomes. Possible links between endothelium-independent microvascular coronary reactivity and adverse outcomes remain uncertain.

METHODS

As part of the National Heart, Lung and Blood Institute-sponsored WISE (Women's Ischemia Syndrome Evaluation), we investigated relationships between major adverse outcomes and baseline coronary flow reserve (CFR) after intracoronary adenosine in 189 women referred to evaluate suspected ischemia.

RESULTS

At a mean of 5.4 years, we observed significant associations between CFR and major adverse outcomes (death, nonfatal myocardial infarction, nonfatal stroke, or hospital stay for heart failure). An exploratory receiver-operator characteristic analysis identified CFR <2.32 as the best discriminating threshold for adverse outcomes (event rate 26.7%; and >or=2.32 event rate 12.2%; p = 0.01). Lower CFR was associated with increased risk for major adverse outcomes (hazard ratio: 1.16, 95% confidence interval: 1.04 to 1.30; p = 0.009). This held true among the 152 women without obstructive coronary artery disease (CAD) (hazard ratio: 1.20, 95% confidence interval: 1.05 to 1.38; p = 0.008). The CFR significantly improved prediction of adverse outcomes over angiographic CAD severity and other risk conditions.

CONCLUSIONS

Among women with suspected ischemia and atherosclerosis risk factors, coronary microvascular reactivity to adenosine significantly improves prediction of major adverse outcomes over angiographic CAD severity and CAD risk factors. These findings suggest that coronary microvessels represent novel targets for diagnostic and therapeutic strategies to predict and limit adverse outcomes in women. (Women's Ischemia Syndrome Evaluation [WISE]; NCT00000554).

Limitations and potential clinical application on contrast echocardiography

Myocardial contrast echocardiography (MCE) is a relatively simple myocardial perfusion imaging technique which should be used in different clinical settings. The ability of MCE to provide a comprehensive assessment of cardiac structure, function, and perfusion is likely to make it the technique of choice for non-invasive cardiac imaging.Contrast agents are encapsulated microbubbles (MB) filled with either air or high-molecular-weight gas. They are innocuous, biologically inert and when administered intravasculary, the sound backscatter from the blood poll is enhanced because MB have the enormous reflective ability due to a large acoustic impedance mismatch between the bubble gas and surrounding blood.MCE is an ideal imaging tool for the assessment of left heart contrast and the myocardial microcirculation. MCE detects contrast MB at the capillary level within the myocardium and, thus, has the potential to assess tissue viability and the duration of the contrast effect. MCE was equivalent to SPECT for the detection of CAD with a tendency toward higher sensitivity of MCE compared with SPECT in microvascular disease and CAD. MCE is also a bedside technique that can be used early in patients presenting with acute heart failure to rapidly assess LV function (regional and global) and perfusion (rest and stress).