Myocardial perfusion imaging using a technetium-99m sestamibi in asymptomatic and low risk for coronary artery disease patients with diagnosed systemic lupus erythematosus

The Role of Cardiac Imaging in the Evaluation of Cardiac Involvement in Systemic Diseases

For systemic diseases like rheumatoid arthritis, systemic lupus erythematosus (SLE), systemic sclerosis, systemic vasculitis, myopathies, and mixed connective tissue diseases, cardiac disease is a major contributing factor for morbidity and mortality. The cardiovascular manifestations are the result of various pathophysiological components, which complicate management. Furthermore, the signs and symptoms can be subtle and missed due to the complex nature of the underlying condition. As a result, various imaging approaches play an imperative role in diagnosis and prognosis. The evolving role of these modalities could lead to risk stratification and improved therapies in the future. In conclusion, our review article will highlight the role of cardiac imaging in the evaluation of cardiac involvement for systemic diseases.

Myocardial Perfusion Abnormalities in Young and Premenopausal Women with Systemic Lupus Erythematosus, Detected with 99MTC MIBI Myocardial Perfusion Scintigraphy - Prevalence and Correlation with Proatherogenic Factors

INTRODUCTION

Atherosclerosis in young and premenopausal women with systemic lupus erythematosus (SLE) is frequent, premature and progressive. Although asymptomatic or with atypical clinical presentation, the patients are at high risk of cardiac events. Aim of this study is to estimate the risk profile for atherogenesis and the prevalence of myocardial perfusion abnormalities with 99mTc myocardial perfusion scintigraphy (MPS) in young and premenopausal women.

MATERIAL AND METHODS

Sixty female patients, aged 30-72 years (divided into two subgroups - patients under 45 years of age and patients over 45 years), diagnosed with SLE for over of 5 years, in active phase of the disease were analyzed for disease activity scores (SLEDAI), the immunologic status of the disease (ANA and a-DNA antibodies in the serum), procoagulant tendency (antiphospholipid antibodies-APhL and lupus-anticoagulant-LAC), the activity of the inflammatory process (hsCRP), the anti-SLE therapeutic approach and the presence of traditional risk factors for atherosclerosis (BMI, smoking, hypertension, hyperlipidemia, diabetes, and familial history for the CAD). Using one-day Dipyridamol - Rest 99mTc SPECT Gated MPS SPECT the extent, severity and reversibility of myocardial perfusion abnormalities were estimated, along with summed scores at stress, rest and summed difference scores and left ventricle volumes and ejection fraction.

RESULTS

Abnormal MPS SPECT were detected in 27/60 or in 45% of patients, with one vessel affection of 66.7% (18/27pts) of LAD and 14.8% (4/27pts) o RCA and with two vessel disease of LAD/RCA in 2/27 pts (7.4%) and LAD/Cx in 3/27pts (11.1%). Myocardial perfusion abnormalities were equally prevalent in subgroups of patients younger than 45 years (44,4%) and in patients older than 45 years (45.5%) (ns). The subgroups did not differ significantly concerning the extent of perfusion abnormalities (9,8±3.2% of LV myocardial mass vs. 9,8±7.1%,ns), their severity (with predominance of mild perfusion defects, 48,6% vs. 51,3%,ns) and reversibility (reversible in 41.3% and 58.6%, ns). The differences between the summed scores of severity and the extent of ischemia in the two subgroups were statistically nonsignificant. Younger patients had significantly higher end-diastolic, end-systolic and stroke volumes during stress and rest conditions, compared to older patients (p<0,01) although there were no differences in systolic function, which was not affected in either of the groups as expressed threw ejection fraction. Although nonsignificant, younger patients had higher values of hsCRP and higher procoagulant activity (positive aPhL, LAC) while they were with more active disease activity, with higher SLEDAI score compared to older patients (p=0.028). Higher SLEDAI score and LV volumes, especially EDV at stress were identified as predictor of abnormal MPS in younger groups and more aggressive multidrug anti SLE treatment as predictor of normal MPS.

CONCLUSION

The prevalence and characteristics of myocardial perfusion abnormalities in young SLE are equal as the same in older SLE patients, which indicates the presence of premature, accelerated atherosclerosis in young cohort of patients with SLE. Younger SLE patients with pure disease control (higher SLEDAI score, less aggressive treatment, high hsCRP values and pronounced procoagulant tendency) should undergo screening for myocardial perfusion abnormalities s using 99mTc MIBI MPS).

Early Detection of Silent Myocardial Impairment in Drug-Naive Patients With New-Onset Systemic Lupus Erythematosus: A Three-Center Prospective Study

OBJECTIVE

Cardiac magnetic resonance imaging (MRI) has enabled the assessment of myocardial features, from tissue characteristics to functional changes, in patients with systemic lupus erythematosus (SLE). Echocardiography, however, detects cardiac decompensation. This study was undertaken to investigate the use of cardiac MRI to explore early warning signs of silent cardiac involvement and determine treatment timing in SLE.

METHODS

Clinical assessment and cardiac MRI studies were performed in 50 drug-naive patients with new-onset SLE, 60 patients with longstanding SLE, and 50 healthy subjects in a 3-center prospective study.

RESULTS

Analysis of cardiac enzymes, the presence and size of regional myocardial fibrosis as indicated by late gadolinium enhancement, strain changes, and biventricular ejection fraction did not indicate cardiac impairment in the patients with new-onset SLE. Native myocardial T1 and extracellular volume (ECV), which are extracellular matrix indices, were elevated in the patients with new-onset SLE (mean ± SD 1,369 ± 79 msec versus 1,092 ± 57 msec in the control group for native T1; 32 ± 5% versus 24 ± 3% in the control group for ECV; P < 0.001 for both). The elevation was independent of SLE disease activity.

CONCLUSION

This is the first study to indicate that drug-naive patients with new-onset SLE, even those with inactive disease, are likely to have silent cardiac impairment. Structural and functional changes in the myocardium are related to SLE disease stage; this finding indicates the value of early detection of myocardial involvement. Native myocardial T1 values and ECV, rather than currently used clinical rheumatic and cardiac indices, could serve as early detection markers of myocardial injury before the presence of visual fibrosis and functional decompensation.

Complementary role of cardiovascular imaging and laboratory indices in early detection of cardiovascular disease in systemic lupus erythematosus

Background

Cardiovascular disease (CVD) has been documented in >50% of systemic lupus erythematosus (SLE) patients, due to a complex interplay between traditional risk factors and SLE-related factors. Various processes, such as coronary artery disease, myocarditis, dilated cardiomyopathy, vasculitis, valvular heart disease, pulmonary hypertension and heart failure, account for CVD complications in SLE.

Methods

Electrocardiogram (ECG), echocardiography (echo), nuclear techniques, cardiac computed tomography (CT), cardiovascular magnetic resonance (CMR) and cardiac catheterization (CCa) can detect CVD in SLE at an early stage. ECG and echo are the cornerstones of CVD evaluation in SLE. The routine use of cardiac CT and nuclear techniques is limited by radiation exposure and use of iodinated contrast agents. Additionally, nuclear techniques are also limited by low spatial resolution that does not allow detection of sub-endocardial and sub-epicardial lesions. CCa gives definitive information about coronary artery anatomy and pulmonary artery pressure and offers the possibility of interventional therapy. However, it carries the risk of invasive instrumentation. Recently, CMR was proved of great value in the evaluation of cardiac function and the detection of myocardial inflammation, stress-rest perfusion defects and fibrosis.

Results

An algorithm for CVD evaluation in SLE includes clinical, laboratory, ECG and echo assessment as well as CMR evaluation in patients with inconclusive findings, persistent cardiac symptoms despite normal standard evaluation, new onset of life-threatening arrhythmia/heart failure and/or as a tool to select SLE patients for CCa.

Conclusions

A non-invasive approach including clinical, laboratory and imaging evaluation is key for early CVD detection in SLE.

Comparison of 180° and 360° Arc Data Acquisition to Measure Scintigraphic Parameters from Gated Single Photon Emission Computed Tomography Myocardial Perfusion Imaging: Is There Any Difference?

Objective:

The aim of the current study was to compare 180° and 360° data collection modes to measure end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) values of the cardiac system by gated myocardial perfusion tomography.

Methods:

Thirty-three patients underwent gated myocardial perfusion tomography. Single photon emission computed tomography data of patients’ heart were acquired by 180°, 45° left posterior oblique to 45° right anterior oblique, and 360° to obtain EDV, ESV, EF and cardiac volume changes (V1, V2, V3, V4, V5, V6, V7 and V8) throughout each cardiac cycle.

Results:

Results of the current study indicated that there were no significant differences between 180° and 360° angular sampling in terms of measuring EDV, ESV and EF in myocardial perfusion imaging. Cardiac volume change patterns during a cardiac cycle were also similar in 360° and 180° scans. We also observed that there was no difference in EDV, ESV and EF values between the group with stress induced by exercise and the group with stress imposed by dipyridamole.

Conclusion:

As there is no difference between 180°and 360° cardiac scanning in terms of EDV, ESV and EF, half-orbit scan is recommended to study these cardiac system parameters because it offers more comfort to patients and a shorter scanning time.

Association between serum total antioxidant status and flow-mediated dilation in patients with systemic lupus erythematosus: an observational study

Objective:

Endothelial dysfunction (ED) is a condition that involves increased oxidative stress and decreased total antioxidant status (TAS) levels. Systemic lupus erythematosus (SLE) is also associated with ED. We aimed to determine the association between serum TAS and ED as assessed by flow-mediated dilation (FMD) in patients with SLE.

Methods:

Thirty-four patients with stable SLE who were not undergoing any treatment and 39 healthy volunteers without any overt cardiovascular disease were included in this cross-sectional study. Doppler ultrasound was used to measure FMD to assess ED in the study groups. Serum TAS levels were measured using a TAS kit. High-sensitivity C-reactive protein (hs-CRP) and anticardiolipin antibody (aCLA) levels were also measured to assess the inflammatory state. The SLE group further was divided into 2 groups according to presence or absence of aCLA. SLE disease activity was assessed using the SLE disease activity index (SLEDAI). Regression analysis was used to define independent predictors.

Results:

The mean TAS levels were significantly lower in patients with SLE than in controls (1.60±0.11 versus 1.73±0.15 mmol/L, p<0.001). hs-CRP levels were significantly higher in patients with SLE than in controls (8.2±6.0 vs. 2.9±4.0 mg/L; p<0.001), particularly in SLE patients with positive aCLA when compared with SLE patients with negative aCLA (13.8±4.3 vs. 5.6±4.8 mg/L, p<0.001). The FMD percent was significantly lower in patients with SLE than in controls (8.1±4.9 vs. 10.6±4.7, p=0.04). There was a significant positive correlation between FMD and TAS in the SLE group (r=0.448, p=0.008) and the control group (r=0.367, p=0.03) and a significant negative correlation between FMD and serum hs-CRP (r=-0.368, p=0.04) in only the SLE group. In multiple linear regression analysis, TAS, hs-CRP and SLEDAI were independently correlated with FMD (ß=0.50, p=0.003; ß=-0.33, p=0.03; and ß=-0.36, p=0.03; respectively).

Conclusion:

Patients with SLE who have no overt cardiovascular disease are at increased risk for ED and this may be associated with underlying inflammation and impairment of TAS.