Usefulness of technetium-99 m sestamibi myocardial perfusion SPECT in detection of cardiovascular involvement in patients with systemic lupus erythematosus or systemic sclerosis

Sudden cardiac death, arrhythmias and abnormal electrocardiography in systemic sclerosis: A systematic review and meta-analysis

OBJECTIVE

To calculate the frequency of sudden cardiac death(SCD), arrhythmia and conduction defects in SSc.

METHODS

MEDLINE/EMBASE were searched to January 2023. English-language studies reporting the incidence/frequency of SCD, arrhythmia and electrocardiography(ECG) abnormalities in SSc were included. Odds ratios(OR), estimations of annual incidence or pooled frequencies were calculated.

RESULTS

Seventy-nine studies(n = 13,609 participants with SSc) were included in the meta-analysis. Methodology and outcomes were heterogeneous. Ten studies included cohorts with known/suspected SSc-associated heart involvement(SHI), generally defined as clinically-manifest cardiac disease/abnormal cardiac investigations. The incidence of SCD in SHI was estimated to be 3.3% annually(n = 4 studies, 301PY follow-up). On ambulatory ECG, 18% of SHI cohorts had non-sustained ventricular tachycardia(NSVT; n = 4, 95%CI3.2-39.3%), 70% frequent premature ventricular complexes (PVCs; n = 1, 95%CI34.8-93.3%), and 8% atrial fibrillation (AF; n = 1, 95%CI4.2-13.6%). Nineteen studies included participants without SHI, defined as normal cardiac investigations/absence of cardiac disease. The estimated incidence of SCD was approximately 2.9% annually (n = 1, 67.5PY). Compared to healthy controls, individuals without SHI demonstrated NSVT 13.3-times more frequently (n = 2, 95%CI2-102), and paroxysmal supraventricular tachycardia 7-times more frequently (n = 4, 95%CI3-15). Other ambulatory ECG abnormalities included NSVT in 9% (n = 7, 95%CI6-14%), >1000 PVCs/24 h in 6% (n = 2, 95%CI1-13%), and AF in 7% (n = 5, 0-21%). Fifty studies included general SSc cohorts unselected for cardiac disease. The incidence of SCD was estimated to be 2.0% annually(n = 4 studies, 1646PY). Unselected SSc cohorts were 10.5-times more likely to demonstrate frequent PVCs (n = 2, 95%CI 2-59) and 2.5-times more likely to have an abnormal electrocardiography (n = 2, 95%CI1-4).

CONCLUSIONS

The incidence of SCD in SSc is estimated to be 1.0-3.3% annually, at least 10-fold higher than general population estimates. Arrhythmias including NSVT and frequent PVCs appear common, including amongst those without known/suspected SHI.

SARS-CoV-2 infection and SLE: endothelial dysfunction, atherosclerosis, and thrombosis

An increased risk of atherosclerotic and thrombotic complications characterizes connective tissue diseases. Endothelial dysfunction is the basis for the initiation and progression of atherosclerosis and thrombosis. We present systemic lupus erythematosus (SLE) as a model rheumatic disease with endothelial dysfunction and discuss its mechanisms, factors that influence the early onset and rapid progression of atherosclerosis, and the increased risk of thromboembolic events. We focus on established methods to improve endothelium function, including statins, antiplatelet, and antithrombotic therapy. Hypercoagulable and hypofibrinolitic states and a hyperinflammatory response characterize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Several pathogenic mechanisms are typical for an acute phase of Covid-19 post-Covid syndrome and connective tissue diseases: endothelial dysfunction, elevated antiphospholipid antibody titer, activation of the complement system, and formation of extracellular neutrophil traps (NET). The current review discusses the mechanisms underlying SLE and the COVID-19 in the context of endothelial function, atherosclerosis, and thrombosis (Graphical abstract). Key Points • The pathophysiology of systemic lupus erythematosus (SLE) and Covid-19 shows some similarities, such as endothelial cell activation and dysfunction, the activation of complementary systems, the presence of antiphospholipid antibodies, and the formation of extracellular neutrophil traps. • Autoimmunity in both diseases creates the basis for hyperinflammatory, hypercoagulable, and hypofibrinolitic states and their thromboembolic complications. • This paper presents our perspective on the mechanisms behind the cardiovascular manifestations of SLE and COVID-19, with a particular emphasis on endothelial dysfunction. Covid-19 and systemic lupus erythematosus-potential similarities in pathophysiology. Figures of the panel illustrate the clinical manifestations of endothelial dysfunction, atherosclerosis, and thromboembolism, including coronary artery disease ([A] coronary angiography with left anterior descending artery stenosis and [B] scintigraphy with reduced perfusion in the myocardial apical segments), stroke ([C] carotid angiography, left carotid artery occlusion) and pulmonary embolism ([D]computed tomography with thrombus in the right pulmonary artery).

Multimodality Cardiac Imaging in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematous (SLE) is an autoimmune disease with a wide range of cardiovascular complications. The main manifestations include diseases of the coronary arteries, valves, pericardium, and myocardium. Multimodality cardiovascular imaging techniques are critical for evaluating the extent of cardiac manifestations in SLE patients, which can provide valuable prognostic information. However, their utility has previously not been well defined. This review provides a state-of-the-art update on the cardiovascular manifestations of lupus, as well as the role of multimodality cardiac imaging in guiding management of patients with SLE.

Heart failure in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by a constellation of cardiovascular (CV) and non-CV manifestations. Even though CV complications such as accelerated atherosclerosis and elevated risk of myocardial infarction (MI) have been recognized for many years, there is limited evidence regarding SLE and its association with heart failure (HF). Traditional risk factors of atherosclerotic CV disease, as well as various SLE manifestations and therapies, independently or together, increase the risk of HF in this population. There is a need for sufficiently powered intervention studies focusing on specific risk factors to improve CV outcomes in SLE patients.

Echocardiographic findings in asymptomatic systemic lupus erythematosus patients

The aim of this study is to use transthoracic echocardiographic (TTE) imaging methods to identify cardiac dysfunction in asymptomatic systemic lupus erythematosus (SLE) patients and to determine the association between echocardiographic findings and serology. This is a prospective cross-sectional study where 50 patients with confirmed diagnoses of SLE were recruited from rheumatology outpatient clinics. Clinical and serological evaluation to confirm the diagnosis of lupus was done in all patients. Fifty SLE patients, 46 (92%) females and 4 (8%) males, were recruited. Anti-double-stranded DNA (Anti-dsDNA), anticardiolipin, lupus anticoagulant, and anti-β2-glycoproteins were positive in 52.1, 32.6, 13.3, and 15.6%, respectively. Transthoracic echocardiogram revealed mitral regurgitation in 16 patients (32%), pericardial effusion in16 patients (32%), aortic regurgitation in five patients (10%), and tricuspid regurgitation in 10 patients (20%). Eleven patients had left ventricular hypertrophy (22%), and eight patients had ventricular systolic dysfunction (16%). Only four patients had ventricular diastolic dysfunction (8%). A significant association between mitral and tricuspid valve regurgitation and positive anti-dsDNA (p < 0.018, p < 0.006, respectively) was found. Positive anticardiolipin antibodies, lupus anticoagulant, and anti-β 2 glycoprotein antibodies were also associated with mitral valve regurgitation (p values 0.044, 0.006, and 0.023), respectively. Active disease assessed by Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was found to be associated with increased risk of mitral valvular leaflet thickening (p value 0.028). Performing regular transthoracic echocardiogram in asymptomatic SLE patients is important for early detection and appropriate treatment of cardiac lesions. Clinically quiescent but serologically active disease and presence of antiphospholipid antibodies were associated with structural heart abnormalities.

Assessment of coronary flow reserve using a combination of planar first-pass angiography and myocardial SPECT: Comparison with myocardial (15)O-water PET

Coronary flow reserve (CFR), defined as the ratio of maximum coronary flow increase from baseline resting blood flow, is one of the most sensitive parameters to detect early signs of coronary arteriosclerosis at the microvascular level. Myocardial perfusion PET is a well-established technology for CFR measurement, however, availability is still limited. The aim of this study is to introduce and validate myocardial flow reserve measurement by myocardial perfusion SPECT.

METHODS

Myocardial perfusion SPECT at rest and ATP stress (0.16mg/Kg/min) was performed in 10 patients with known coronary artery disease. Immediately after the injection of Tc-99m sestamibi (MIBI), left ventricular (LV) dynamic planar angiographic data were obtained for 90s. Coronary flow reserve index as measured by MIBI SPECT (CFRMIBI) was calculated as follows: CFRMIBI=CmsSbmb/CmbSbms, where subscripts b, s, Cm, and Sbm indicate baseline, during stress, myocardial counts with MIBI SPECT, and integral of LV counts with first pass angiography, respectively. Additionally, standard stress/rest (15)O-water PET to estimate CFR was performed in all patients as standard of reference.

RESULTS

CFRMIBI increased in conjunction with CFR, but underestimated blood flow at high flow rates. The relationship between CFRMIBI (Y) and CFRPET (X) was well fitted as follows: Y=1.40x(1-exp(1.79/x)) (r=0.84).

CONCLUSIONS

The index of CFRMIBI reflects the CFR by (15)O-water PET but underestimates flow at high flows, maybe as a reflection of pharmacokinetic limitations of MIBI.

Pathogenic immunity in systemic lupus erythematosus and atherosclerosis: common mechanisms and possible targets for intervention

Systemic lupus erythematosus (SLE) is an autoimmune disorder that primarily affects young women and is characterized by inflammation in several organs including kidneys, skin, joints, blood and nervous system. Abnormal immune cellular and humoral responses play important roles in the development of the disease process. Impaired clearance of apoptotic material is a key factor contributing to the activation of self-reactive immune cells. The incidence of atherosclerotic cardiovascular disease (CVD) is increased up to 50-fold in patients with SLE compared to age- and gender-matched controls, and this can only partly be explained by traditional risk factors for CVD. Currently, there is no effective treatment to prevent CVD complications in SLE. Traditional preventive CVD therapies have not been found to significantly lower the incidence of CVD in SLE; therefore, there is a need for novel treatment strategies and increased understanding of the mechanisms involved in the pathogenesis of CVD complications in SLE. The pathogenic immune responses in SLE and development of atherosclerotic plaques share some characteristics, such as impaired efferocytosis and skewed T-cell activation, suggesting the possibility of identifying novel targets for intervention. As novel immune-based therapies for CVD are being developed, it is possible that some of these may be effective for the prevention of CVD and for immunomodulation in SLE. However, further understanding of the mechanisms leading to an increased prevalence of cardiovascular events in SLE is critical for the development of such therapies.

Myocardial perfusion defects in scleroderma detected by contrast-enhanced cardiovascular magnetic resonance

PURPOSE

The authors investigated whether contrast-enhanced cardiovascular magnetic resonance (CMR) imaging may be used to detect early cardiac involvement in patients with systemic sclerosis (SSc).

MATERIALS AND METHODS

Twenty-six SSc patients (nine with diffuse cutaneous SSc and 17 with limited cutaneous SSc) and 13 sex- and age-matched healthy controls (HC) were studied. Contrast-enhanced CMR allowed the analysis of first-pass images (areas of hypo-enhancement indicating perfusion defects) and delayed images (persistent hyper-enhancement indicating fibrosis). Clinical variables including disease duration and presence of major visceral complications of SSc were investigated in each patient.

RESULTS

Perfusion defects were detected in 53.8 % of SSc patients but in none of the HC. Perfusion abnormalities were detected in 28.6 % of SSc patients with disease duration less than 2 years and in 29.2 % of asymptomatic SSc patients. Delayed contrast enhancement was present in 25 % of SSc patients but not in HC. All patients with delayed contrast enhancement showed first-pass hypoperfusion. Right ventricular wall thickness was significantly increased in all SSc patients when compared to HC (p < 0.001); a similar trend was observed when SSc patients without pulmonary arterial hypertension were analysed (p < 0.04). A trend to lower end-diastolic and end-systolic right ventricular volumes in SSc versus HC was observed (p < 0.05 and p < 0.04, respectively).

CONCLUSIONS

Myocardial hypoperfusion is common in SSc and occurs early in the course of the disease. Co-localisation of perfusion defects and delayed contrast enhancement indicative of fibrosis suggests that myocardial hypoxia may play a role in the pathogenesis of myocardial fibrosis.

QT dispersion in patients with systemic lupus erythematosus: the impact of disease activity

Background

Patients with systemic lupus erythematosus (SLE) have increased cardiovascular morbidity and mortality. Although autopsy studies have documented that the heart is affected in most SLE patients, clinical manifestations occur in less than 10%. QT dispersion is a new parameter that can be used to assess homogeneity of cardiac repolarization and autonomic function. We compared the increase in QT dispersion in SLE patients with high disease activity and mild or moderate disease activity.

Methods and Results

One hundred twenty-four patients with SLE were enrolled in the study. Complete history and physical exam, ECG, echocardiography, exercise test and SLE disease activity index (SLEDAI) were recorded. Twenty patients were excluded on the basis of our exclusion criteria. The patients were divided to two groups based on SLEDAI: 54 in the high-score group (SLEDAI > 10) and 50 in the low-score group (SLEDAI < 10).

QT dispersion was significantly higher in high-score group (58.31 ± 18.66 vs. 47.90 ± 17.41 respectively; P < 0.004). QT dispersion was not significantly higher in patients who had received hydroxychloroquine (54.17 ± 19.36 vs. 50.82 ± 15.96, P = 0.45) or corticosteroids (53.58 ± 19.16 vs. 50.40 + 11.59, P = 0.47). There was a statistically significant correlation between abnormal echocardiographic findings (abnormalities of pericardial effusion, pericarditis, pulmonary hypertension and Libman-Sacks endocarditis) and SLEADI (P < 0.004).

Conclusions

QT dispersion can be a useful, simple noninvasive method for the early detection of cardiac involvement in SLE patients with active disease. Concerning high chance of cardiac involvement, cardiovascular evaluation for every SLE patient with a SLEDAI higher than 10 may be recommended.

Trial registration

Clinicaltrial.gov registration NCT01031797

Influence of chronic inflammation and autoimmunity on coronary calcifications and myocardial perfusion defects in systemic lupus erythematosus patients

Objective

Conventional risk factors for coronary artery disease fail to explain the increased frequency or cardiovascular morbidity in systemic lupus erythematosus (SLE) patients. This study was conducted to determine the possible influence of autoimmune and inflammatory phenomena markers on coronary artery calcifications and myocardial perfusion abnormalities in SLE patients.

Materials and methods

Multi-detector computed tomography (MDCT)-based coronary calcium scoring and single photon emission computerized tomography (SPECT) studies (Tc-99m sestamibi) were performed in 60 SLE patients in stable clinical condition, without a prior history of coronary artery disease. Laboratory evaluation included serum C-reactive protein (CRP), complement C3c and C4 components and antiphospholipid antibodies (aPL). The latter included anticardiolipin (aCL) and anti-β2-glycoprotein I (aβ2GPI) antibodies, of both IgG and IgM classes, and lupus anticoagulant (LA) in plasma.

Results

SPECT revealed persistent perfusion defects in 22 (36.7%) patients and exercise-induced defects in eight (13.3%), while MDCT revealed coronary calcifications in 15 (25%). Calcium scores ranged from 1 to 843.2 (mean 113.5 ± 259.7). No association was found between conventional coronary artery disease risk factors (obesity, hypertension, tobacco use, hyperlipidaemia, diabetes) nor CRP, C3c or C4 levels and coronary calcifications or myocardial perfusion defects. On the contrary, in patients with these pathologies, augmented autoimmunization was found, reflected by increased aCL IgG and antiβ2GPI IgG levels. In patients with aCL IgG >20 RU/ml or antiβ2GPI IgG >3 RU/ml, the relative risk of coronary calcification formation was 4.1 compared to patients with normal values. Accordingly, in LA-positive patients the relative risk of coronary calcification formation was 4.4 compared to LA-negative patients.

Conclusions

Conventional risk factors for coronary artery disease as well as markers of an ongoing inflammation did not show any association with perfusion defects and/or coronary artery calcifications in SLE patients. On the contrary, calcified atherosclerotic plaques and myocardial perfusion defects were observed mainly in patients with elevated levels of anticardiolipin and aβ2GPI antibodies of the IgG class. It might be speculated that coronary artery calcifications and perfusion defects are a result of antiphospholipid antibodies-induced coronary artery microthrombosis.

Association of heart structure and function abnormalities with laboratory findings in patients with systemic lupus erythematosus

Conventional risk factors of coronary artery disease fail to explain the increased frequency of cardiovascular morbidity in patients with systemic lupus erythematosus (SLE). The study was conducted to determine possible association between the heart structure and function abnormalities with established prognostic value assessed by non-invasive imaging techniques and markers of autoimmune and inflammatory phenomena typical for SLE. Echocardiography and single photon emission computerized tomography (SPECT; Tc-99m-MIBI) at rest were performed in 60 SLE patients in a stable clinical condition of their disease. Laboratory evaluation included serum levels of C-reactive protein (CRP), complement C3c and C4 components and antiphospholipid antibodies (aPL). The latter included serum anticardiolipin (aCL) and anti-β2-glycoprotein I (antiβ2GPI) antibodies, both of IgG and IgM class, and lupus anticoagulant (LA) in plasma. Echocardiography revealed pathologic thickening of valvular leaflets and/or pericardium in more than 60% of patients. Right ventricular systolic pressure (RVSP) was elevated (>30 mmHg) in 16.7%. Myocardial perfusion defects were present in 36.7% of patients, despite normal ECG recordings and a lack of clinical symptoms of myocardial ischaemia. There was a significant association between thickening of valvular leaflets and/or pericardium and high CRP and low C3c and C4 concentrations. On the other hand, increased RVSP and the presence of myocardial perfusion defects were associated with the presence of anticardiolipin and antiβ2GPI antibodies of the IgG class. Increased anticardiolipin IgG levels predicted perfusion defects in SPECT study with 100% sensitivity and 68% specificity, whereas elevated antiβ2GPI IgG levels predicted RVSP elevation (>30 mmHg) with 100% sensitivity and 78% specificity. In stable SLE patients pericardial and valve abnormalities may be associated with markers of an ongoing inflammation. Also, pulmonary systolic pressure elevation and myocardial perfusion defects are combined with elevated levels of anticardiolipin and antiβ2GPI antibodies of the IgG class. These results indicate that even clinically silent pulmonary hypertension and myocardial perfusion defects in SLE patients could be causally related to the presence of antiphospholipid antibodies.

Influence of atorvastatin on coronary calcifications and myocardial perfusion defects in systemic lupus erythematosus patients: a prospective, randomized, double-masked, placebo-controlled study

Introduction

Mortality in systemic lupus erythematosus (SLE) patients is influenced by an increased occurrence of severe cardiovascular complications. Statins have been proven to protect a wide spectrum of SLE patients from these complications. This study was conducted to determine the possible efficacy of atorvastatin in SLE patients as assessed by multi-detector computed tomography (MDCT)-based coronary calcium scoring and single photon emission computed tomography (SPECT) of the myocardium.

Methods

Sixty SLE patients in stable clinical conditions were randomized to receive either atorvastatin (40 mg daily; n = 28) or placebo (n = 32). Clinical and biochemical evaluation together with MDCT-based coronary calcium scoring and SPECT studies (Tc-99 m sestamibi) were performed at the time of randomization and after 1 year of treatment.

Results

At randomization, SPECT revealed perfusion defects at rest in 22 (36.7%) patients and exercise-induced defects in 8 (13.3%), whereas MDCT revealed coronary calcifications in 15 subjects (25%). Coronary calcium deposits increased after 1 year in the placebo group (plaque volume change from 35.2 ± 44.9 to 62.9 ± 72.4, P < 0.05; calcium score from 32.1 ± 39.1 to 59.5 ± 64.4; P < 0.05), but not in the atorvastatin group (plaque volume 54.5 ± 62.4 vs. 51.0 ± 47.6, P not significant; calcium score 44.8 ± 50.6 vs. 54.9 ± 62.5, P not significant). The atorvastatin group showed a decrease in total serum cholesterol (from 5.1 ± 1.2 to 4.4 ± 0.7 mmol/L, P < 0.05), LDL cholesterol (2.9 ± 1.0 to 2.3 ± 0.6 mmol/L, P < 0.05), triglycerides (1.6 ± 0.6 to 1.2 ± 0.5 mmol/L, P < 0.05), and C-reactive protein (CRP) (4.4 ± 4.1 to 2.7 ± 1.7 mg/L, P < 0.05). There was no change in the mean Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score in patients from both groups. Perfusion defects observed at randomization showed no change after one year treatment with atorvastatin.

Conclusions

In SLE patients 40 mg of atorvastatin daily for 1 year led to a decrease in serum lipids and CRP levels. Additionally the progression of atherosclerosis, as assessed by MDCT-based coronary calcium scoring, is restrained by atorvastatin treatment. The value of statin treatment in patients with SLE free from cardiovascular disease clinical symptoms should be addressed in large, prospective clinical trials.

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

INTRODUCTION

The aim of the present study was to evaluate technetium-99m sestamibi single photon emission tomography (SPECT) myocardial perfusion imaging (MPI) and its association with some clinical and laboratory parameters in an asymptomatic systemic lupus erythematosus (SLE) population.

MATERIALS AND METHODS

Twenty-one subjects with SLE and no suspected or documented coronary artery disease (CAD) accomplished myocardial perfusion imaging. Some SLE and CAD parameters were also evaluated in association with myocardial SPECT.

RESULTS

Twenty-one women with a diagnosis of SLE (mean age 36.9 ± 12.8) entered the study. All patients were in the low-risk category for CAD pretest; however, abnormal myocardial perfusion results were found in eight (38%) patients. Amongst the traditional CAD risk factors, there was a significant association between the presence of dyslipidemia and myocardial perfusion abnormalities (P= 0.047). However, we found no significant association between other traditional and SLE-specific risk factors.

CONCLUSION

This study's significant finding was that asymptomatic CAD is common in SLE patients, even in those thought to be low risk for CAD and in the absence of cardiac symptoms.

Cardiac magnetic resonance imaging with pharmacological stress perfusion and delayed enhancement in asymptomatic patients with systemic sclerosis

OBJECTIVE

To assess cardiac involvement in asymptomatic patients with systemic sclerosis (SSc) by cardiac magnetic resonance imaging (MRI).

METHODS

Ten asymptomatic patients with SSc (all female; mean age 59.5+/-9.4 yrs) underwent contrast enhanced cardiac MRI on a 1.5 T MRI device. Adenosine triphosphate was used for stress and rest perfusion to assess perfusion defects due to microvascular impairment or ischemia, and delayed enhanced (DE) imaging was obtained for the assessment of myocardial necrosis and fibrosis. We evaluated the pathophysiological associations of stress perfusion combined with DE imaging with SSc disease severity measures.

RESULTS

Stress perfusion defects were seen in 5 out of 9 patients (56%): 4 had nonsegmental subendocardial perfusion defects and one had a segmental subendocardial perfusion defect. Three patients were found to have DE. DE was not observed in any patient without perfusion defect; and among the 5 patients with perfusion defects, 3 (60%) had DE. Two of the 3 had DE in segments not matching the region of nonsegmental perfusion defects. The remaining one had a segmental subendocardial DE matching the region of a segmental perfusion defect. Perfusion defects were seen in 75% of patients with a history of digital ulceration compared to only 20% of those without history of ulceration.

CONCLUSION

Subclinical myocardial involvement, as detected by cardiac MRI, was frequent in asymptomatic patients with SSc. Cardiac MRI may aid in understanding the pathophysiological mechanism of SSc.

Myocardial Perfusion Imaging in Assessing Risk of Coronary Events in Patients with Systemic Lupus Erythematosus

Objective.

Classic risk factors do not fully account for the increased risk of coronary artery disease (CAD) in systemic lupus erythematosus (SLE), making identification of the subset of patients at risk challenging. In this prospective cohort study we investigated whether myocardial perfusion defects in SLE are predictive of CAD events, independently of traditional Framingham risk factors.

Methods.

We performed myocardial perfusion imaging in 122 women with SLE who did not have a history of CAD. Patients had clinical and serologic evaluation, and an assessment of cardiac risk factors. They were then followed for the occurrence of CAD events. Cox regression models were used to determine independent predictors of CAD.

Results.

Forty-six (37.7%) patients had perfusion defects. Median followup was 8.7 years, during which 15 CAD events occurred (1 myocardial infarction, 14 angina). Cox modeling showed that myocardial perfusion defects are strongly predictive of CAD [hazard ratio (HR) 13.0, 95% CI 2.8 to 60.1, p = 0.001]. Although the 10-year Framingham risk score was significantly predictive of CAD (HR 1.8, 95% CI 1.1 to 2.9, p = 0.01), the risk scores in groups with normal and abnormal scans were similar to the “low-risk” general population.

Conclusion.

In women with SLE, myocardial perfusion defects are strongly and independently predictive of CAD. Our findings suggest that myocardial perfusion imaging to assess risk of future coronary events should be considered in women with SLE.

QT dispersion increases in patients with systemic lupus erythematosus

Although autopsy studies have documented that heart is affected in most of systemic lupus erythematosus (SLE) patients, clinical manifestations occur in less than 10%. QT dispersion, a new parameter that can be used to assess homogeneity of cardiac repolarization and autonomic function, has not been studied in SLE patients. The aim of our study was to evaluate the QT dispersion (QTd) in SLE patients without overt cardiac involvement. Eighty-three patients with a diagnosis of SLE (mean age 41+/-13) and age- and sex-matched 77 healthy control subjects (mean age 43+/-10) were enrolled in the study. All subjects had their complete history taken, laboratory examination, and transthoracic echocardiography (ECG). Patients with cardiac disease, hypertension, diabetes, or taking medications that may effect QTd or any ECG abnormalities were excluded. Resting 12-lead ECG were recorded for measurement of QTd. None of the patients and control subjects had overt cardiac involvement. The mean SLE duration was 86.5+/-15.4 months. QT dispersion was significantly greater in SLE patients than incontrol subjects (55.2+/-24.7 vs 20.7+/-5.3 ms, respectively; p<0.001). There was no correlation between QTd and duration of SLE, SLEDAI-K score, corticosteroid usage, and presence of anti SS-A antibody. QT dispersion is significantly increased in SLE patients without overt cardiac involvement. Our result suggests that prolonged QT dispersion can be a useful noninvasive and simple method for early detection of cardiac involvement in SLE patients.

Myocardial Damages in Systemic Sclerosis Detected by Gated Myocardial Perfusion SPECT and Sympathetic Imaging

BACKGROUND

Cardiac involvement is an important factor for the appropriate management of systemic sclerosis (SSc). The possibility for detecting early myocardial damage was investigated using (99m)Tc methoxyisobutylisonitrile (MIBI) gated perfusion single photon emission computed tomography (SPECT) and (123)I metaiodobenzylguanidine (MIBG) sympathetic imaging.

METHODS AND RESULTS

Twenty-three patients with SSc and 14 control subjects were studied. The severity of SSc was defined by disease type and semi-quantitative skin thickness scores. A myocardial perfusion study was performed using (99m)Tc MIBI exercise--rest study, and systolic and diastolic parameters were calculated from the volume curve of the gated SPECT. (123)I MIBG was evaluated by segmental defects, a heart-to-mediastinum ratio and washout rate (WR). No significant exercise-induced ischemia was observed and the left ventricular ejection fraction was within normal range in patients with SSc. However, diastolic function calculated by time to peak filling (TPF) in the early diastole was significantly prolonged in SSc compared with the control group (184+/-35 ms, 160+/-25 ms, p=0.030) and more rapid MIBG WR from the myocardium (18.2+/-7.0% vs 11.1+/-4.3%, p=0.0015). Compared with the control group, the severe group with either diffuse SSc or a skin thickness score >or=10 had more prolonged TPF/RR interval than the less severe group. Both diastolic and sympathetic abnormalities were observed in 7 (30%) patients, and 1 abnormality in 17 (74%) patients with SSc.

CONCLUSIONS

In patients with SSc, either diastolic dysfunction or sympathetic derangement, or both were observed even without induced ischemia and normal ventricular contractility. Based on these subclinical early findings, further follow-up studies are recommended.