Myocardial perfusion abnormalities in asymptomatic patients with systemic lupus erythematosus

Lupus carditis: evaluation with technetium-99m MIBI myocardial SPECT and heart rate variability

The objective of this paper was to investigate the incidence of myocardial perfusion defects in patients with systemic lupus erythematosus (SLE) associated with dysautonomic alterations. Twenty patients without any sign or symptoms of heart disease, selected from a larger population of patients with SLE, underwent technetium-99m sestamibi (Tc-99m MIBI) single photon emission computed tomography (SPECT), at rest and after dipyridamole infusion; they also underwent heart rate variability (HRV) examination by a 24 hour ambulatory electrocardiography, analyzing in the time domain the standard deviation of the R-R intervals average (SDNN) and the percentage of R-R adjacent intervals differing from each other more than 50 msec (pNN50); in the frequency domain the low (LF) and high frequencies (HF) were analyzed. Twenty healthy volunteers served as control group for heart rate variability. At MIBI-SPECT examination, the scan was found abnormal in 15 patients and normal in five: three patients demonstrated reversible defects in the anteroseptal region, four had irreversible defects in a region (two in the anteroseptal region and two in the lateral region), two had rest defects in two different regions (lateral and inferior, lateral and anteroseptal) that improved during dipyridamole scan, and six had both reversible and irreversible defects: four in a single segment (three anteroseptal and one lateral, and two in two different regions, particularly anteroseptal and lateral, lateral and inferior). All 20 patients showed significantly lower HRV parameters in comparison with the control group, except for pNN50, which indicates decreased physiologic periodic fluctuations of the autonomic nervous system. In six patients who underwent coronary angiography, the epicardial vessels were found completely normal. In view of the high incidence of myocardial hypoperfusion in patients with HRV alterations, the authors hypothesize that autonomic dysfunction may be associated with microvascular disease or metabolic alteration. They also believe that MIBI scintigraphy is a suitable technique in detecting myocardial damage in SLE patients free of clinical manifestation.

Prevalence and risk factors of carotid plaque in women with systemic lupus erythematosus

OBJECTIVE

To determine the prevalence of carotid atherosclerosis and associated risk factors in women with systemic lupus erythematosus (SLE).

METHODS

Carotid plaque and intima-media wall thickness (IMT) were measured by B-mode ultrasound in women with SLE. Risk factors associated with carotid plaque and IMT were determined at the time of the ultrasound scan and included traditional cardiovascular risk factors, SLE-specific variables, and inflammation markers.

RESULTS

The 175 women with SLE were predominantly white (87%), with a mean age of 44.9 years (SD 11.5). Twenty-six women (15%) had a previous arterial event (10 coronary [myocardial infarction or angina], 11 cerebrovascular [stroke or transient ischemic attack], and 5 both). The mean +/- SD IMT was 0.71 +/- 0.14 mm, and 70 women (40%) had focal plaque. Variables significantly associated with focal plaque (P < 0.05) included age, duration of lupus, systolic, diastolic, and pulse pressure, body mass index, menopausal status, levels of total and low-density lipoprotein (LDL) cholesterol, fibrinogen and C-reactive protein levels, SLE-related disease damage according to the Systemic Lupus International Collaborating Clinics (SLICC) damage index (modified to exclude cardiovascular parameters), and disease activity as determined by the Systemic Lupus Activity Measure. Women with longer duration of prednisone use and a higher cumulative dose of prednisone as well as those with prior coronary events were more likely to have plaque. In logistic regression models, independent determinants of plaque (P < 0.05) were older age, higher systolic blood pressure, higher levels of LDL cholesterol, prolonged treatment with prednisone, and a previous coronary event. Older age, a previous coronary event, and elevated systolic blood pressure were independently associated with increased severity of plaque (P < 0.01). Older age, elevated pulse pressure, a previous coronary event, and a higher SLICC disease damage score were independently related to increased IMT (P < 0.05).

CONCLUSION

B-mode ultrasound provides a useful noninvasive technique to assess atherosclerosis in women with SLE who are at high risk for cardiovascular disease. Potentially modifiable risk factors were found to be associated with the vascular disease detected using this method.

Cardiovascular manifestations of systemic autoimmune diseases

The systemic autoimmune diseases are a protean group of illnesses that primarily affect the joints, muscles, and connective tissue. All aspects of the cardiovascular system can be involved with clinical consequences ranging from asymptomatic abnormalities to serious life-threatening conditions. This article discusses the cardiovascular manifestations of the systemic autoimmune diseases with particular focus on clinical pathophysiology and management.

Prevention and treatment of adverse effects of corticosteroids in systemic lupus erythematosus

Corticosteroid therapy has had a major impact on improvement in disease activity and long-term survival in patients with systemic lupus erythematosus (SLE). Unfortunately, the therapeutic advantages are accompanied by many manifestations of toxicity, some of which are short term and potentially reversible, while others cause chronic irreversible damage. Many of these features of toxicity have similar presentations to manifestations of SLE disease activity, and must be distinguished in the individual patient. The features of corticosteroid toxicity are reviewed in this chapter, and means of prevention and/or treatment are discussed.

Assessment of myocardial perfusion and function in childhood systemic lupus erythematosus

OBJECTIVES

To determine the prevalence of abnormalities in myocardial perfusion or function in children with systemic lupus erythematosus (SLE), and describe potential factors that may predict their development.

STUDY DESIGN

Patients (n = 40; 30 female) were enrolled through the Lupus Clinic at The Hospital for Sick Children between 1990 and 1992. Resting and exercise thallium myocardial perfusion scans, radionuclide angiography with multiple gated acquisition (MUGA), and resting M-mode and two-dimensional echocardiography were performed.

RESULTS

All patients were free of symptoms, and none had a history of ischemic heart disease. Their median age was 15.9 years (range 10.5 to 19.8 years) at enrollment. Abnormalities of coronary perfusion were found in 5 (16%) of 31 patients (95% confidence interval: 3%, 29%) and included a large fixed perfusion defect in 1; 5 of 27 MUGA scans showed marginally low left ventricular ejection fractions at rest, whereas all had normal exercise responses. In the group with abnormal thallium scans, three of five patients had antiphospholipid antibodies detected, and two of four had an abnormal plasma lipid profile. This group tended to have a shorter disease duration and had received a lower cumulative dose of corticosteroids; these differences were not statistically significant compared with the group with normal scans.

CONCLUSION

Asymptomatic abnormalities of myocardial perfusion occur in children with SLE and are more common than previously suspected. Patients with these abnormalities of myocardial perfusion may be predisposed to the previously recognized early-onset ischemic heart disease seen in adults with SLE.

Omega-3 fatty acid supplementation in clinical and experimental lupus nephritis

Nutrients rich in omega-3 fatty acids (fish oil and flaxseed) have the potential to abrogate inflammatory and atherosclerotic mechanisms known to be involved in the pathogenesis of vascular damage of systemic lupus erythematosus nephritis. Fish oil dietary supplementation decreases proteinuria and preserves renal morphology in the NZB/NZW, BXSB, and MRL/lpr mouse models of lupus nephritis and decreases mortality in the NZB/NZW and BXSB models. The anti-inflammatory and anti-atherosclerotic potential, coupled with the animal experimental data, encouraged us to carry out a dosing study of low (6 g) and higher (18 g) doses of fish oil (MaxEPA) therapy in human lupus nephritis. At the lower dose, the fish oil inhibited inflammatory mechanisms; at the higher dose, it altered both the inflammatory and atherosclerotic mechanisms. This led to a double-blind cross-over study of fish oil therapy in 26 patients with lupus nephritis followed for 2 years 10 weeks. The fish oil dietary supplementation had no significant effect on proteinuria, isotope glomerular filration rate, disease activity index, or steroid consumption. However, it did have a significant effect on lipid levels. The cross-over design suffered carryover effects (even with a 10-week wash-out period) and placebo effects of the olive oil, which created a risk of type II error. Our interest in omega-3 fatty acids led us to assess the effects of dietary supplementation with flaxseed. Not only is the flaxseed a major source of alpha-linolenic acid but it is also the richest natural source of lignan, a natural platelet-activating factor receptor antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)

Fish oil in lupus nephritis: clinical findings and methodological implications

Our objective was to determine the effects of fish oil on renal function, symptoms, and serum lipids in patients with lupus nephritis. A double-blind, randomized crossover trial of fish oil versus placebo (olive oil) was done on 26 patients with confirmed systemic lupus; 21 completed the study. Intervention was fish oil or placebo, 15 g/day, for one year followed by a 10 week wash-out period, and then the reverse treatment for one year. At baseline and six month intervals, we measured platelet membrane fatty acids, indices of renal function, a disease activity index, serum lipid levels, blood pressure, serum viscosity and red cell flexibility. We found that platelet membrane phospholipids were uniformly affected by fish oil supplementation (P < 0.001) but with significant carry-over effects despite a 10 week wash-out period. Glomerular filtration rate and serum creatinine were not affected. A non-significant reduction in mean (SE) 24-hour proteinuria occurred, from 1424.1 mg (442.7) on placebo to 896.7 mg (352.2) on fish oil (P = 0.21). Fish oil lowered serum triglycerides from 1.89 (0.25) mmol/liter to 1.02 (0.11) mmol/liter (P = 0.004). VLDL cholesterol decreased markedly whether patients initially received fish oil or placebo (P = 0.004). The size of the reduction was affected by the order of treatment (P = 0.03), but parallel comparisons were significant before the crossover (P = 0.0006). With the possible exception of bleeding time, no other treatment effects were shown with fish oil. However, treatment order effects were seen in urinary IgG excretion (P = 0.03), whole blood viscosity (P < 0.0001), red cell flexibility (P = 0.004), and bleeding time (P = 0.06). In conclusion, one year of dietary supplementation with fish oil in patients with stable lupus nephritis did not improve renal function or reduce disease activity, but did alter some lipid parameters. Hitherto unreported carry-over effects and treatment order effects caused by the olive oil created a risk of type II error, and bear methodologic consideration in the design of future studies.

Risk factors for coronary artery disease in patients with systemic lupus erythematosus

PURPOSE

To estimate the frequency of and examine risk factors for coronary artery disease (CAD) in patients with systemic lupus erythematosus (SLE) in a prospective longitudinal study.

PATIENTS AND METHODS

Patients were SLE are enrolled in The Johns Hopkins Lupus Cohort, a prospective study of outcomes in 229 subjects with SLE. CAD was defined as angina, myocardial infarction, or sudden death. Data on CAD risk factors were obtained prospectively every 3 months and were analyzed using univariate and multiple logistic regression.

RESULTS

CAD occurred in 19 (8.3%) of 229 patients with SLE and accounted for 3 (30%) of 10 deaths as of December 31, 1990. Compared to subjects without CAD, those with CAD were more likely to have been older at both diagnosis of SLE (37.1 years versus 28.9 years, p = 0.004) and at entry into the cohort (47.1 years versus 34.7 years, p < 0.0001), to have a longer mean duration of SLE (12.3 years versus 8.1 years, p = 0.013) and a longer mean duration of prednisone use (14.3 years versus 7.2 years, p < 0.0001), to have a higher mean serum cholesterol (271.2 mg/dL versus 214.9 mg/dL, p < 0.0001) or a cholesterol level greater than 200 mg/dL (odds ratio [OR] 14.5, 95% confidence intervals [CI] 1.9, 112.1), and to have both a history of hypertension (OR 3.5, 95% CI 1.3, 9.6) and a history of use of antihypertensive medications (OR 5.5, 95% CI 1.8, 17.2). There were no significant associations with other known CAD risk factors such as smoking, diabetes, family history of CAD, race, or sex, or variables related to steroid therapy including the presence of cushingoid features or ever use of corticosteroids. The best multiple logistic regression model for CAD included age at diagnosis, duration of prednisone use, requirement for antihypertensive treatment, maximum cholesterol level, and obesity (using NHANES-II [National Health and Nutrition Examination Survey] definitions).

CONCLUSION

Primary and secondary prevention strategies directed at hypertension, hypercholesterolemia, and obesity, as well as other known CAD risk factors, should be routinely employed in the management of patients with SLE.

Myocardial systolic function in systemic lupus erythematosus: a study based on radionuclide ventriculography

We assessed left ventricular systolic function by means of radionuclide ventriculography in 20 consecutive unselected patients with systemic lupus erythematosus. All patients had normal left ventricular systolic function (defined as ejection fraction greater than 45%) in a resting state. Regional wall motion abnormalities were, however, seen in 4 patients (20%). Of these 20 patients, 8 were able to exercise on a bicycle ergometer. These patients were subjected to exercise radionuclide ventriculography. Of these 8 patients, 3 (37.5%) had an abnormal ventriculographic response to exercise (as evidenced by a subnormal rise in ejection fraction or a fall, appearance of a new regional wall motion abnormality or worsening of a pre-existing one). This probably reflects subclinical left ventricular dysfunction unmasked by the stress of exercise. The clinical significance of these abnormalities on long-term myocardial function and their possible reversibility with remission of the disease needs to be assessed in future studies.

Doppler echocardiographic evaluation of left ventricular diastolic function in patients with systemic lupus erythematosus

Subclinical myocardial involvement frequently occurs in patients with systemic lupus erythematosus (SLE). In this study, left ventricular diastolic function was assessed in 58 patients (54 female and 4 male; mean age 32 +/- 11 years) and in 40 sex-matched and age-matched healthy control subjects (37 female and 3 male; mean age 33 +/- 9 years) by means of pulsed Doppler echocardiography. All subjects had no clinical evidence of overt myocardial disease or abnormal left ventricular systolic function. Compared with the control group, patients with SLE had significantly prolonged isovolumic relaxation time (62 +/- 12 vs 80 +/- 14 msec; p less than 0.01), reduced peak early diastolic flow velocity (peak E) (82 +/- 18 vs 76 +/- 16 cm/sec; p less than 0.05), increased peak late diastolic flow velocity (peak A) (45 +/- 7 vs 53 +/- 8 cm/sec; p less than 0.01), reduced E/A ratio (1.81 +/- 0.32 vs 1.46 +/- 0.29; p less than 0.001), and lower deceleration rate of early diastolic flow velocity (EF slope) (489 +/- 151 vs 361 +/- 185 cm/sec2; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Frequency of angiographic detection and quantitative assessment of coronary arterial disease one and three years after cardiac transplantation

The reported high incidence of coronary atherosclerosis in many transplant series led us to critically review our experience in 83 patients who have had selective coronary angiography at greater than or equal to 1 years after transplantation. Angiograms were reviewed for evidence of coronary vascular disease, and quantitative analysis of multiple coronary artery segments was performed in serial films. Qualitative analysis revealed only 3 of 83 patients with any angiographic abnormality at follow-up, 1 with minimal luminal irregularities in the right coronary artery at 1 year, a second with a 50% diameter stenosis of the proximal left anterior descending artery and minimal irregularity of the proximal circumflex artery at 1 year and a third patient who developed a new 30% diameter eccentric proximal right coronary artery stenosis at 3-year follow-up. The cumulative incidence of graft vascular disease assessed angiographically was therefore 2% at 1 year and 4% at 3 years. Quantitative analysis, however, showed a significant decrease in coronary artery luminal diameter over time. The mean left main coronary artery diameter decreased from 5.4 +/- 0.9 mm at 1 year to 4.7 +/- 0.8 mm at 3 years (p = 0.0007).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiovascular involvement in systemic lupus erythematosus

SLE is an inflammatory disease of unknown etiology with the potential of affecting virtually all organ systems. Cardiovascular involvement occurs frequently, although it is often mild enough not to cause clinical concern. Pericarditis is most commonly subclinical, noted only on echocardiogram. Pericardial fluid, which can accumulate rapidly enough to cause tamponade, is inflammatory in nature and can totally mimic infection. The occurrence of Libman-Sacks endocarditis, usually a pathological diagnosis of little clinical significance, has little if any correlation with the presence of audible murmurs. However, valve replacement is occasionally necessary secondary to sterile destruction. These valvular lesions can also embolize or become infected. The incidence of ischemic coronary disease is increased, both secondary to premature atherosclerosis and, rarely, coronary arteritis. Conduction disease and arrhythmias are infrequently reported in adult patients, but congenital CHB has been noted in children born to mothers who have circulating anti-Ro antibody. Evidence is accumulating that suggests there is a mild cardiomyopathy associated with SLE that may be due to thrombotic or inflammatory microvascular coronary disease. Acute clinical myocarditis also rarely occurs. Therapeutically, at present, a reasonable course would seem to be to limit all known possible contributing factors to premature coronary artery and myocardial disease (hypertension, hypercholesterolemia, smoking, steroid therapy, etc), to be vigilant about recognizing the rarer complications associated with SLE (infectious pericarditis and endocarditis, coronary arteritis, pericardial tamponade, clinical myocarditis), and to remember that these uncommon complications are indeed uncommon. The importance of vigorously treating systemic hypertension cannot be overstressed.