The Heart and APS

Prevalence and adverse consequences of delayed diagnosis and misdiagnosis in thrombotic antiphospholipid syndrome. An observational cohort study and a review of the literature

OBIECTIVES

This study aims to prospectively evaluate the frequency and adverse consequences of diagnostic delay and misdiagnosis in a cohort of patients with thrombotic antiphospholipid syndrome (TAPS). In addition, a systematic review of the literature concerning the diagnostic delay and misdiagnosis of TAPS was carried out.

METHODS

Patient enrollment occurred between 1999 and 2022. The study group was formed by TAPS patients whose diagnosis was delayed and those who were misdiagnosed. The control group was made up of patients who were timely and correctly diagnosed with TAPS.

RESULTS

The literature review showed 42 misdiagnosed patients, 27 of them were in one retrospective cohort study and 15 in 13 case reports. One hundred sixty-one out of 189 patients (85.2%) received a timely, correct diagnosis of TAPS; 28 (14.8%) did not. The number of patients with diagnostic issues was significantly higher for the first period (1999-2010), and the number of patients with a correct diagnosis was significantly higher for the second one (2011-2022). When the clinical and laboratory characteristics of the patients with delayed diagnosis were compared with those with misdiagnosis, there was a significantly higher number of severe adverse consequences characterized by permanent disability or death in the latter group. The two most common types of misdiagnoses were systemic lupus erythematosus (6 cases, 46.1%) and cardiovascular diseases (4 cases, 30.8%).

CONCLUSIONS

The study demonstrates that although knowledge about TAPS has improved over time, diagnostic delays and errors remains to be addressed as they are strongly associated to adverse consequences. Key Points •Although knowledge of thrombotic antiphospholipid syndrome has improved over time, it is still limited. •Diagnostic delay and misdiagnosis are still an important issue that remains to be addressed as they are strongly associated to adverse consequences. •The three more frequent misdiagnoses are multiple sclerosis, systemic lupus erythematosus and cardiovascular diseases.

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).

Stress perfusion Cardiac Magnetic Resonance in Patients with Antiphospholipid Syndrome

Background:

Antiphospholipid syndrome (APS) is characterized by the combination of recurrent arterial and venous thrombotic events and detection of persistently elevated antiphospholipid antibody titers in the serum or plasma. APS clinical manifestations also include non-thrombotic complications from various organ systems, mainly the CNS, kidneys, and heart. Cardiac manifestations of APS include valvulopathy, myocardial infarction and angina (stable, unstable, and Pritzmental angina). A previously published case series of cardiac magnetic resonance (CMR) in patients with APS has revealed a high rate of asymptomatic myocardial necrosis and scarring, but the prevalence of myocardial ischemia identified as CMR perfusion defects prior to development of necrosis is unknown.

Aims of the study:

To detect CMR imaging markers of myocardial ischemia in APS patients without symptoms of cardiovascular disease (CVD).

Methods:

We will scan fifty APS patients without symptoms of CVD stress-perfusion CMR in a 1.5 Tesla tomographer, after intravenous infusion of adenosine and gadolinium. In addition to markers of cardiac anatomy and function, we will record imaging markers of ischemia and scarring, namely perfusion defects (PDs), and late gadolinium enhancement (LGE). We will perform parametrics using dedicated software in order to derive each patient’s myocardial perfusion reserve index (MPRI). Scans will be reviewed independently by two experienced reviewers, with evaluation of inter- and intra-observer reliability. Statistical hypotheses will be examined using Student’s test and Pearson’s correlation coefficient, or non-parametric equivalents (Kruskall-Wallis and Spearman) for continuous variables, and Fisher’s exact test for binary variables. Linear or logistic regression analyses will be used to investigate APS-related determinants of subclinical myocardial ischemia.

Anticipated benefits:

We expect to identify CMR imaging patterns characteristic of APS, which will allow proactive therapeutic interventions for primary prevention of CVD and guide further research into the pathogenesis of APS cardiac manifestations.

Cardiac involvement in antiphospholipid syndrome: The diagnostic role of noninvasive cardiac imaging

OBJECTIVES

The antiphospholipid syndrome (APS) is an autoimmune disorder of acquired hypercoagulability characterized by vascular thrombosis, increased pregnancy morbidity, and elevated levels of antiphospholipid antibodies. Cardiac involvement in APS may be presented as heart valve disease affecting approximately a third of patients or less frequently as intracardial thombosis, pulmonary hypertension, right or left ventricular dysfunction, micro-vascular thrombosis, coronary artery, or micro-vascular disease with overt or silent clinical presentation.

METHODS

Noninvasive cardiovascular imaging plays a crucial role in the evaluation of heart involvement in APS. Transthoracic or transoesophageal echocardiography enable early, accurate diagnosis and severity assessment of HVD as well as of ventricular dysfunction and pulmonary hypertension. Studies by echocardiography and nuclear imaging have detected abnormalities in myocardial perfusion in approximately 30% of primary APS. CT scan is the technique of choice for the assessment of pulmonary embolism and can effectively detect intracardiac thrombi. Myocardial perfusion defects have been detected by 13N-ammonia PET in 40% of APS. Cardiovascular magnetic resonance (CMR) has identified an unexpectedly high prevalence of occult myocardial scarring and endomyocardial fibrosis in APS, and is the technique of choice, if quantification of heart valve disease and stress myocardial perfusion-fibrosis is needed.

RESULTS

Noninvasive, nonradiating imaging techniques, such as echocardiography and CMR are superior to CT or nuclear techniques and are of great value for the diagnosis and follow-up of both clinically overt and silent cardiac disease in APS.

CONCLUSIONS

The high incidence of cardiac involvement in APS demands early diagnosis/treatment and multimodality cardiovascular imaging is of great importance.

Cutting-edge issues in coronary disease and the primary antiphospholipid syndrome

Antiphospholipid syndrome (APS) is the most frequent cause of venous and arterial thrombotic events in young patients. The brain arterial tree is primarily affected, but coronary ischemic manifestations are also relatively frequent. Coronary involvement was suggested to be closely related to the accelerated atherosclerosis linked to the underlying disease in APS associated to systemic autoimmune diseases, in particular, systemic lupus erythematosus. However, arterial ischemic events can occur in primary APS--with no other systemic disorders--even in the absence of traditional cardiovascular risk factors and overt atherosclerosis. From a biological point of view, this finding speaks in favor for a pro-coagulant activity of anti-phospholipid antibodies rather than for their role in atherosclerotic plaque formation. On the other hand, the clinical challenge is to avoid the risk to misdiagnose young patients with potentially life-threatening symptoms, such as myocardial infarction (MI). In fact, the occurrence of nonspecific symptoms related to coronary ischemic events is frequently misdiagnosed because of its rarity in young patients. This issue is well illuminated by two cases of MI in young patients reported in the manuscript together with a systematic review of the associations and implications of coronary ischemic events in APS.

Cardiac manifestations of rheumatological conditions: a narrative review

Cardiovascular diseases are common in systemic rheumatologic diseases. They can be presented at the time of diagnosis or after diagnosis. The cardiac involvements can be the first presentation of rheumatologic conditions. It means that a patient with rheumatologic disease may go to a cardiologist when attacked by this disease at first. These manifestations are very different and involve different structures of the heart, and they can cause mortality and morbidity of patients with rheumatologic diseases. Cardiac involvements in these patients vary from subclinical to severe manifestations. They may need aggressive immunosuppressive therapy. The diagnosis of these conditions is very important for choosing the best treatment. Premature atherosclerosis and ischemic heart disease are increased in rheumatoid arthritis and systemic lupus erythematosus, and may be causes of mortality among them. The aggressive control of systemic inflammation in these diseases can reduce the risk of cardiovascular disease especially ischemic heart disease. Although aggressive treatment of primary rheumatologic diseases can decrease mortality rate and improve them, at this time, there are no specific guidelines and recommendations, to include aggressive control and prevention of traditional risk factors, for them.

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.

Left-sided cardiac valvulitis in tristetraprolin-deficient mice: the role of tumor necrosis factor alpha

Inflammation may play a role in the etiology of both degenerative and rheumatic cardiac valve diseases. We report here that mice deficient in tristetraprolin (TTP), a protein with known anti-inflammatory functions, develop severe left-sided cardiac valvulitis. TTP is an mRNA binding protein that inhibits inflammation by destabilizing the mRNA encoding tumor necrosis factor alpha (TNF). This leads in turn to a TNF-excess syndrome characterized by systemic inflammation. Evaluation of hearts from TTP-/- mice demonstrated gross thickening of the mitral and aortic but not the tricuspid or pulmonary valves, accompanied by inflammatory cell infiltrates. To determine whether TNF played a role in the development of this valvulitis, we examined mice deficient in both TNF receptors and in TTP; four of five of these mice exhibited no histological evidence of valvulitis, but one mouse had aortic valve leaflet thickening with a cellular infiltrate. Four additional mice had no external evidence of valvular thickening. Cardiac valves of transgenic mice expressing human TNF developed mild aortic valve leaflet edema without evidence of hypercellularity. Thus, TTP deficiency in mice leads to left-sided cardiac valvulitis with prominent inflammatory cell involvement, due, at least in part, to excess TNF. These findings support the potential involvement of TNF and inflammation in the development of cardiac valve disease in man.

Patients' experiences of a diagnosis of Hughes' syndrome

The objectives of the study were to describe the experience of patients immediately prior to a diagnosis of Hughes syndrome (HS) or antiphospholipid syndrome and post-diagnosis. A questionnaire survey was carried out set in the Hughes Syndrome Foundation, St. Thomas' Hospital, London, 2006. Participants were all patients who are members of the Hughes Syndrome Foundation. The main outcome measures were responses to a questionnaire relating to the experiences of people with a diagnosis of HS, such as number of hospitalisations, number of consultants seen, number of miscarriages, etc. A total of 157 patients completed the questionnaire, giving a response rate of 60.4%. Most (85%) were women and mean age was 46 years (SD 12). The median time to diagnosis was 3 years. The median number of consultants seen was 2 (max 19) with a median time in hospital pre-diagnosis of 10 days. The most common initial diagnoses were migraines, multiple sclerosis and systemic lupus erythematosus. Among women, 46% had had a miscarriage. Two thirds of respondents thought a blood test would have led to an earlier diagnosis. Comments from patients indicated a lack of awareness among specialists and general practitioners. The survey demonstrated a long time lag for diagnosis of Hughes syndrome, with increased costs to the NHS and emotional and financial cost to the patient. Greater awareness of this condition would benefit patients and the NHS.