Next generation sequencing analysis of patients with familial cervical artery dissection

Genetic variants in patients with multiple arterial aneurysms

PURPOSE

The aim of this study was to identify causal genetic variants in patients with multiple arterial aneurysms.

METHODS

From a total cohort of 3107 patients diagnosed with an arterial aneurysm from 2006 to 2016, patients with known hereditary connective tissue diseases, vasculitis, or other arterial pathologies (n = 918) were excluded. Of the remaining cohort (n = 2189), patients with at least 4 aneurysms at different arterial locations (n = 143) were included. Nine blood samples of respective patients were available and derived from the institutional vascular biomaterial bank, and analyzed by whole exome sequencing (WES). Possible candidate variants were selected based on in silico predictions: (I) Truncating variants or (II) Variants that were classified as likely pathogenic (SIFT score < 0.05 or PolyPhen score > 0.9) and with low (< 0.001) or unknown gnomAD allele frequency. The human genome databases GeneCards and MalaCards were used to correlate the variants with regard to possible associations with vascular diseases.

RESULTS

A total of 24 variants in 23 different genes associated with vascular diseases were detected in the cohort. One patient with eight aneurysms was heterozygous for a variant in SMAD3, for which pathogenic variants are phenotypically associated with Loeys-Dietz syndrome 3. A heterozygous variant in TNXB was found in a patient with five aneurysms. Homozygous or compound heterozygous pathogenic variants in this gene are associated with Ehlers-Danlos syndrome (classical-like). Another patient with six aneurysms carried two heterozygous TET2 variants together with a heterozygous PPM1D variant. Pathogenic variants in these genes are associated with clonal hematopoiesis of indeterminate potential (CHIP), a known risk factor for cardiovascular disease.

CONCLUSION

All nine patients in this study carried variants in genes associated with vascular diseases. Current knowledge of the specific variants is insufficient to classify them as pathogenic at the present time, underlining the need for a better understanding of the consequences of genetic variants. WES should be considered for patients with multiple arterial aneurysms to detect germline variants and to improve clinical management for the individual and family members.

Diagnosis and treatment of cardiovascular disease in patients with heritable connective tissue disorders or heritable thoracic aortic diseases

Patients with heritable connective tissue disorders (HCTDs), represented by Marfan syndrome, can develop fatal aortic and/or arterial complications before age 50. Therefore, accurate diagnosis, appropriate medical treatment, and early prophylactic surgical treatment of aortic and arterial lesions are essential to improve prognosis. Patients with HCTDs generally present with specific physical features due to connective tissue abnormalities, while some patients with heritable thoracic aortic diseases (HTADs) have few distinctive physical characteristics. The development of genetic testing has made it possible to provide accurate diagnoses for patients with HCTDs/HTADs. This review provides an overview of the diagnosis and treatment of HCTDs/HTADs, including current evidence on cardiovascular interventions for this population.

Treatment and Outcomes of Cervical Artery Dissection in Adults: A Scientific Statement From the American Heart Association

Cervical artery dissection is an important cause of stroke, particularly in young adults. Data conflict on the diagnostic evaluation and treatment of patients with suspected cervical artery dissection, leading to variability in practice. We aim to provide an overview of cervical artery dissection in the setting of minor or no reported mechanical trigger with a focus on summarizing the available evidence and providing suggestions on the diagnostic evaluation, treatment approaches, and outcomes. Writing group members drafted their sections using a literature search focused on publications between January 1, 1990, and December 31, 2022, and included randomized controlled trials, prospective and retrospective observational studies, meta-analyses, opinion papers, case series, and case reports. The writing group chair and vice chair compiled the manuscript and obtained writing group members' approval. Cervical artery dissection occurs as a result of the interplay among risk factors, minor trauma, anatomic and congenital abnormalities, and genetic predisposition. The diagnosis can be challenging both clinically and radiologically. In patients with acute ischemic stroke attributable to cervical artery dissection, acute treatment strategies such as thrombolysis and mechanical thrombectomy are reasonable in otherwise eligible patients. We suggest that the antithrombotic therapy choice be individualized and continued for at least 3 to 6 months. The risk of recurrent dissection is low, and preventive measures may be considered early after the diagnosis and continued in high-risk patients. Ongoing longitudinal and population-based observational studies are needed to close the present gaps on preferred antithrombotic regimens considering clinical and radiographic prognosticators of cervical artery dissection.

Missense Variants in COL4A1/2 Are Associated with Cerebral Aneurysms: A Case Report and Literature Review

BACKGROUND

Although cerebral aneurysm (CA) is a defining complication of COL4A1/2-related vasculopathy, the specific factors influencing its onset remain uncertain. This study aimed to identify and analyze these factors.

METHODS

We described a family presenting with a novel variant of the COL4A1 gene complicated with CA. Concurrently, an exhaustive review of previously documented patients with COL4A1/2-related vasculopathy was conducted by sourcing data from PubMed, Web of Science, Google Scholar, and Ichushi databases. We compared the variant types and locations between patients with CA (positive group) and those without CA (negative group).

RESULTS

This study included 53 COL4A1/2 variants from 76 patients. Except for one start codon variant, all the identified variants in CA were missense variants. Otherwise, CA was not associated with other clinical manifestations, such as small-vessel disease or other large-vessel abnormalities. A higher frequency of missense variants (95.5% vs. 58.1%, p = 0.0035) was identified in the CA-positive group.

CONCLUSIONS

CA development appears to necessitate qualitative alterations in COL4A1/2, and the underlying mechanism seems independent of small-vessel disease or other large-vessel anomalies. Our findings suggest that a meticulous evaluation of CA is necessary when missense variants in COL4A1/2 are identified.

Unraveling the Links between Chronic Inflammation, Autoimmunity, and Spontaneous Cervicocranial Arterial Dissection

Advances in imaging techniques have led to a rise in the diagnosis of spontaneous cervicocranial arterial dissection (SCCAD), which is now considered a common cause of stroke in young adults. However, our understanding of the pathophysiological mechanisms underlying SCCAD remains limited. Prior studies have proposed various factors contributing to arterial wall weakness or stress as potential causes for SCCAD. A combination of biopsies, case reports, and case-control studies suggests that inflammatory changes and autoimmunity may play roles in the cascade of events leading to SCCAD. In this review, we examine the close relationship between SCCAD, chronic inflammation, and autoimmune diseases, aiming to explore potential underlying pathophysiological mechanisms connecting these conditions. While some relevant hypotheses and studies exist, direct evidence on this topic is still relatively scarce. Further investigation of the underlying mechanisms in larger clinical cohorts is needed, and the exploration of animal models may provide novel insights.

Genetics of spontaneous cervical and coronary artery dissections

Objectives

Spontaneous cervical artery dissections (SCeAD) and coronary artery dissections (SCoAD) are major causes of neurovascular and cardiovascular morbidity in young adults. Although multiple aspects of their etiology are still unknown, most consensuses are focused on the presence of constitutional genetic aspects and environmental triggers. Since recent evidence of genetic contribution points to a possible overlap between these conditions, we aimed to describe current information on SCeAD and SCoAD genetics and their potential shared pathological aspects.

Materials and methods

A narrative review is presented. Publications in English and Spanish were queried using database search. The articles were evaluated by one team member in terms of inclusion criteria. After collecting, the articles were categorized based on scientific content.

Results

Given that patients with SCeAD and SCoAD rarely present connective tissue disorders, other genetic loci are probably responsible for the increased susceptibility in some individuals. The common variant rs9349379 at PHACTR1 gene is associated with predisposition to pathologies of the arterial wall, likely mediated by variations in Endothelin-1 (ET-1) levels. The risk of arterial dissection may be increased for those who carry the rs9349379(A) allele, associated with lower expression levels of ET-1; however, the local effect of this vasomotor imbalance remains unclear. Sex differences seen in SCeAD and SCoAD support a role for sex hormones that could modulate risk, tilting the delicate balance and forcing vasodilator actions to prevail over vasoconstriction due to a reduction in ET-1 expression.

Conclusions

New evidence points to a common gene variation that could explain dissection in both the cervical and coronary vasculatures. To further confirm the risk conferred by the rs9349379 variant, genome wide association studies are warranted, hopefully in larger and ethnically diverse populations.

Arterial dissections: Common features and new perspectives

Arterial dissections, which involve an abrupt tear in the wall of a major artery resulting in the intramural accumulation of blood, are a family of catastrophic disorders causing major, potentially fatal sequelae. Involving diverse vascular beds, including the aorta or coronary, cervical, pulmonary, and visceral arteries, each type of dissection is devastating in its own way. Traditionally they have been studied in isolation, rather than collectively, owing largely to the distinct clinical consequences of dissections in different anatomical locations - such as stroke, myocardial infarction, and renal failure. Here, we review the shared and unique features of these arteriopathies to provide a better understanding of this family of disorders. Arterial dissections occur commonly in the young to middle-aged, and often in conjunction with hypertension and/or migraine; the latter suggesting they are part of a generalized vasculopathy. Genetic studies as well as cellular and molecular investigations of arterial dissections reveal striking similarities between dissection types, particularly their pathophysiology, which includes the presence or absence of an intimal tear and vasa vasorum dysfunction as a cause of intramural hemorrhage. Pathway perturbations common to all types of dissections include disruption of TGF-β signaling, the extracellular matrix, the cytoskeleton or metabolism, as evidenced by the finding of mutations in critical genes regulating these processes, including LRP1, collagen genes, fibrillin and TGF-β receptors, or their coupled pathways. Perturbances in these connected signaling pathways contribute to phenotype switching in endothelial and vascular smooth muscle cells of the affected artery, in which their physiological quiescent state is lost and replaced by a proliferative activated phenotype. Of interest, dissections in various anatomical locations are associated with distinct sex and age predilections, suggesting involvement of gene and environment interactions in disease pathogenesis. Importantly, these cellular mechanisms are potentially therapeutically targetable. Consideration of arterial dissections as a collective pathology allows insight from the better characterized dissection types, such as that involving the thoracic aorta, to be leveraged to inform the less common forms of dissections, including the potential to apply known therapeutic interventions already clinically available for the former.

Cerebral Arteriopathies of Childhood - Current Approaches

Up to more than half of previously healthy children presenting with their first arterial ischemic stroke have a cerebral arteriopathy. Cerebral arteriopathies during childhood can be congenital, reflecting abnormal vessel development, or acquired when caused by disruption of vascular homeostasis. Distinguishing different types of cerebral arteriopathies in children can be challenging but of great clinical value as they may dictate different disease and treatment courses, and clinical and radiologic outcomes. Furthermore, children with stroke due to a specific arteriopathy exhibit distinctive features when compared to those with stroke due to other causes or a different type of arteriopathy. These features become crucial in the management of pediatric stroke by choosing appropriate diagnostic and treatment strategies. The objective of this article is to provide the reader with a comprehensive up-to-date review of the classification, symptoms, diagnosis, treatment, and outcome of cerebral arteriopathies in children.

Cervical Artery Dissections: Etiopathogenesis and Management

Cervical Artery Dissection (CeAD) is a frequent stroke etiology for patients younger than 50 years old. The most common immediate complications related to CeAD are headache and neck pain (65-95%), TIA/ischemic stroke (>50%), and partial Horner's syndrome (25%). The prevailing hypothesis regarding the pathogenesis of sCeAD is that the underlying constitutional vessel wall weakness of patients with sCeAD is genetically determined and that environmental factors could act as triggers. The stroke prevention treatment of CeAD remains controversial, involving anticoagulation or antiplatelet therapy and potentially emergent stenting and/or thrombectomy or angioplasty for selected cases of carotid artery dissection with occlusion. The treatment of headache associated with CeAD depends on the headache phenotype and comorbidities. Radiographically, more than 75% of CeAD cases present with occlusion or non-occlusive stenosis. Many patients demonstrate partial and complete healing, more commonly in the carotid arteries. One-fifth of the patients develop dissecting pseudoaneurysm, but this is a benign clinical entity with an extremely low rupture and stroke recurrence risk. Good recovery is achieved in many CeAD cases, and mortality remains low. Family history of CeAD, connective tissue disorders like Ehlers-Danlos syndrome type IV, and fibromuscular dysplasia are risk factors for recurrent CeAD, which can occur in 3-9% of the cases. This review serves as a comprehensive, updated overview of CeAD, emphasizing etiopathogenesis and management.

Multiple Arterial Dissections and Connective Tissue Abnormalities

Background: Although patients with multiple arterial dissections in distinct arterial regions rarely present with known connective tissue syndromes, we hypothesized that mild connective tissue abnormalities are common findings in these patients. Methods: From a consecutive register of 322 patients with cervical artery dissection (CeAD), we identified and analyzed 4 patients with a history of additional dissections in other vascular beds. In three patients, dermal connective tissue was examined by electron microscopy. DNA from all four patients was studied by whole-exome sequencing and copy number variation (CNV) analysis. Results: The collagen fibers of dermal biopsies were pathologic in all three analyzed patients. One patient carried a CNV disrupting the COL3A1 and COL5A2 genes (vascular or hypermobility type of Ehlers–Danlos syndrome), and another patient a CNV in MYH11 (familial thoracic aortic aneurysms and dissections). The third patient carried a missense substitution in COL5A2. Conclusion: Three patients showed morphologic alterations of the dermal connective tissue, and two patients carried pathogenic variants in genes associated with arterial connective tissue dysfunction. The findings suggest that genetic testing should be recommended after recurrent arterial dissections, independently of apparent phenotypical signs of connective tissue disorders.

Head/neck pain characteristics after spontaneous cervical artery dissection in the acute phase and on a long-run

Objective

Head/neck pain is one of the primary symptoms associated with spontaneous cervical artery dissection. Still, data on pain quality, intensity, and long-term dynamics are scarce.

Methods

Spontaneous cervical artery dissection subjects were included if mural hematoma was visualised through T1 fat-saturated MRI at baseline. All available medical records were evaluated and patients were invited to standardised clinical follow-up visits at least 1 year after the index event.

Results

In total, 279 subjects were included in the ReSect-study with head/neck pain being the most frequent symptom of spontaneous cervical artery dissection (220 of 273, 80.6%). Pain was of pulling nature in 107 of 218 (49.1%), and extended to the neck area in 145 of 218 (66.5%). In those with prior headache history, pain was novel in quality in 75.4% (42 of 55). Median patient-reported pain intensity was 5 out of 10 with thunderclap-type headache being uncommon (12 of 218, 5.5%). Prior to hospital admission, head/neck pain rarely responded to self-medication (32 of 218, 14.7%). Characteristics did not differ between subjects with and without cerebral ischemia. Pain resolved completely in all subjects within a median of 13.5 days (IQR 12). Upon follow-up in 42 of 164 (25.6%) novel recurring headache occurred, heterogeneous in quality, localisation and intensity.

Conclusion

We present an in-depth analysis of spontaneous cervical artery dissection-related head/neck pain characteristics and its long-term dynamics.

Cervical Artery Dissection and Sports

Cervical artery dissection (CeAD) occurring in the context of sports is a matter of concern for CeAD patients. They seek advice on the role of sports in CeAD and on the safety of resuming sports after CeAD. The scarcity of studies and guidelines addressing these issues poses a challenge. We aimed at summarizing the current knowledge about CeAD and sports in order to provide an informed, comprehensive opinion for counseling CeAD patients. We took into account pathophysiological considerations, observations of cases reports, series, and registries, and conclusions by analogy from aortic dissection or inherited connective tissue syndromes. In summary, practicing active sports as the cause of CeAD seems uncommon. It seems recommendable to refrain from any kind of sports activities for at least 1 month, which can be extended in case of an unfavorable clinical or neurovascular course. We recommend starting with sport activities at low intensity—preferably with types of endurance sports—and to gradually increase the pace in an individually tailored manner, taking into circumstances of the occurrences of the CeAD in the individual patient (particularly in relation to sports), the meaning of sports activities for the individual well-being, the presence or absence of comorbidities and of neurological sequela, neurovascular findings, and whether there are signs of an underlying connective tissue alteration. Major limitations and several forms of bias are acknowledged. Still, in the absence of any better data, the summarized observations and considerations might help clinicians in advising and counseling patients with CeAD in clinical practice.

Acute Stanford type B aortic dissection-who benefits from genetic testing?

Background

Stanford type B aortic dissection is a rare, life-threatening complex phenotype associated with several modifiable and genetic risk factors. In the current study of a hospital-based, consecutive series of aortic dissection patients we propose a selection based on age and family history of aortic disease for genetic testing and detection of causative gene variants.

Methods

In this single center cohort study from 2013 to 2018 patients with acute Stanford type B aortic dissections were consecutively treated and analyzed by next generation sequencing based on selection criteria (age of disease onset ≤45 years and/or positive familial history for aortic disease) to detect genome-wide pathogenic variants in protein-coding sequences and to identify large copy number variants (CNV). Variants in a predefined panel of 30 genes associated with the familial thoracic aortic aneurysm and dissection (TAAD) syndrome were evaluated.

Results

From 105 patients nine matched selection criteria for genetic testing. Next-generation sequencing analysis revealed causal variants in FBN1 (fibrillin-1) in three patients: a pathogenic missense variant [c.6661T>C, p.(Cys2221Arg)] and two truncating variants [c.4786C>T, p.(Arg1596Ter)] and [c.6366C>CA, p.(Asp2123GlufsTer5)]. A fourth patient carried a large (>1,000,000 bp) CNV in the long arm of chromosome 10, deleting eleven genes, including the whole ACTA2 (actin alpha 2) gene. The latter two genetic findings have not been reported before.

Conclusions

Selection of patients on the basis of young age and familial inheritance of aortic disease favors the identification of disease-causing genetic variants in a clinical cohort of patients with Stanford type B aortic dissection.

Asymptomatic bilateral common iliac artery dissections in previously undiagnosed vascular Ehlers-Danlos syndrome

We report a case of a 35-year-old woman found to have vascular Ehlers-Danlos syndrome (vEDS) after family history of sudden death due to aortic dissection in her otherwise healthy brother prompted further imaging workup and consideration of an underlying heritable genetic condition. CT angiogram of the aorta with intravenous contrast revealed an abdominal aortic artery dissection below the level of the renal arteries extending from the bifurcation into the left common iliac artery with an additional focal dissection of the right common iliac artery. To the author’s knowledge, this is the first report of asymptomatic bilateral common iliac artery dissections as a part of the initial presentation of a patient with underlying vEDS. Additionally, this case highlights the importance of familial diagnostic screening in inherited vasculopathies. Clinical history, genetic testing and management are discussed.

Rare genetic variants in patients with cervical artery dissection

Introduction

The potential role of genetic alterations in cervical artery dissection (CeAD) pathogenesis is poorly understood. We aimed to identify pathogenic genetic variants associated with cervical artery dissection by using whole exome sequencing.

Patients and methods

CeAD-patients with either a family history of cervical artery dissection (f-CeAD) or recurrent cervical artery dissection (r-CeAD) from the CeAD-databases of two experienced stroke centres were analysed by whole exome sequencing.Variants with allele frequency <0.05 and classified as pathogenic by predicting algorithms (SIFT or Polyphen-2) or the ClinVar database were explored. First, we analysed a panel of 30 candidate genes associated with arterial dissection (any site) or aneurysm according to the OMIM (online Mendelian Inheritance of Men) database. Second, we performed a genome-wide search for pathogenic variants causing other vascular phenotypes possibly related to cervical artery dissection.Findings were classified as CeAD-causing (pathogenic variants in genes from the arterial dissection or aneurysm panel) or suggestive (pathogenic variants in genes associated with other vascular phenotypes and variants of unknown significance in genes from the arterial dissection or aneurysm panel). All other variants were classified as benign/uncertain.

Results

Among 43 CeAD-patients, 28 patients (17 pedigrees) had f-CeAD and 15 had r-CeAD. No CeAD-causing variants were identified in r-CeAD patients. Among f-CeAD-patients, 5/17 pedigrees carried CeAD-causing variants in COL3A1, COL4A1, COL4A3, COL4A4, COL5A1, COL5A2 and FBN1. Suggestive variants in ABCC6, COL3A1, COL5A2, MEF2A, and RNF213 were detected in three pedigrees with f-CeAD and six patients with r-CeAD.Discussion and conclusion: CeAD-causing variants were rare and exclusively found in f-CeAD-patients, suggesting differences between the genetic architectures of f-CeAD and r-CeAD. The identified variants indicate a high genetic heterogeneity of the study sample.

A Unique Recurrent Stroke Case due to Bilateral Vertebral Artery Dissection with Familial Hirschsprung Disease

Vertebral artery (VA) dissection is one major cause of brain infarction in young and middle-aged adults. Risk factors for VA dissection are hypertension, diabetes mellitus, hyperlipidemia, trauma, and genetic factors. A 32-year-old man with familial Hirschsprung disease at the age of 2 presented cerebellar ischemic stroke due to bilateral VA dissections. A stroke recurred within 17 days despite oral dual antiplatelet therapy. Bilateral VA dissections and recurrent dissections are related to genetic mutations associated with connective tissue diseases. A part of familial Hirschsprung disease has genetic factors in common with cerebrovascular disease. There may be a common genetic background between his VA dissection and Hirschsprung disease.

Whole-exome sequencing reveals known and novel variants in a cohort of intracranial vertebral-basilar artery dissection (IVAD)

Intracranial vertebral-basilar artery dissection (IVAD) is an arterial disorder leading to life-threatening consequences. Genetic factors are known to be causative to certain syndromic forms of IVAD. However, systematic study of the molecular basis of sporadic and isolated IVAD is lacking. To identify genetic variants contributing to the etiology of IVAD, we enrolled a cohort of 44 unrelated cases with a clinical diagnosis of isolated IVAD and performed whole-exome sequencing (WES) for all the participants; a trio exome sequencing approach was used when samples from both parents were available. Four previously reported disease-causing heterozygous variants (three in COL3A1 and one in FBN1) and seven novel heterozygous variants in IVAD-related genes were identified. In addition, six variants in novel IVAD genes including two de novo heterozygous nonsynonymous variants (each in VPS52 and CDK18), two stop-gain variants (each in MYH9 and LYL1), and two heterozygous biallelic variants in TNXB were considered to be possibly contributing to the phenotype, with unknown significance according to the existing knowledge. A significantly higher mutational rate of IVAD candidate genes was observed in patients versus our in-house controls (P = 0.002) (DISCO study, http://www.discostudy.org/ , n = 2248). Our study provided a mutational landscape for patients with isolated IVAD.

Familial aortic disease and a large duplication in chromosome 16p13.1

BACKGROUND AND PURPOSE

A recurrent duplication of chromosome 16p13.1 was associated with aortic dissection as well as with cervical artery dissection. We explore the segregation of this duplication in a family with familial aortic disease.

METHODS

Whole exome sequencing (WES) analysis was performed in a patient with a family history of aortic diseases and ischemic stroke due to an aortic dissection extending into both carotid arteries.

RESULTS

The index patient, his affected father, and an affected sister of his father carried a large duplication of region 16p13.1, which was also verified by quantitative PCR. The duplication was also found in clinically asymptomatic sister of the index patient. WES did not detect pathogenic variants in a predefined panel of 11 genes associated with aortic disease, but identified rare deleterious variants in 14 genes that cosegregated with the aortic phenotype.

CONCLUSIONS

The cosegregation of duplication 16p13.1 with the aortic phenotype in this family suggested a causal relationship between the duplication and aortic disease. Variants in known candidate genes were excluded as disease-causing in this family, but cosegregating variants in other genes might modify the contribution of duplication 16p13.1 on aortic disease.

Recurrence of cervical artery dissection

Objective

To explore the recurrence of cervical artery dissection (CeAD).

Methods

A single-center consecutive series of 282 CeAD patients was prospectively recruited during first admission from 1995 to 2012. Patients with a follow-up of at least 1 year (n = 238) were eligible for the current analysis. All patients with clinical symptoms or signs of recurrent CeAD on ultrasound were examined by MRI. Dermal connective tissue morphology was studied in 108 (45.4%) patients.

Results

Median follow-up was 52 months (range 12–204 months). In all, 221 (92.8%) patients presented with monophasic CeAD, including 188 (79.0%) patients with a single CeAD event, 11 (4.6%) with simultaneous dissections in multiple cervical arteries, and 22 (9.2%) with subsequent events within a single phase of 4 weeks. Seventeen patients (7.1%) had late (>1 month after the initial event) recurrent CeAD events, including 5 (2.1%) with multiple recurrences. Patients with late recurrences were younger (37.5 ± 6.9 years) than those without (43.8 ± 9.9; p = 0.011). Ischemic stroke occurred in 164 (68.9%) patients at first diagnosis, but only 4 of 46 (8.7%) subsequent events caused stroke (p < 0.0001), while 19 (41.3%) were asymptomatic. Connective tissue abnormalities were found in 54 (56.3%) patients with monophasic and 8 (66.7%) with late recurrent dissections (p = 0.494).

Conclusion

Twenty-two (9.2%) patients had new CeAD events within 1 month and 17 (7.1%) later recurrences. The risk for new events was significantly higher (about 60-fold) during the acute phase than during later follow-up. Connective tissue abnormalities were not more frequent in patients with late recurrent events than in those with monophasic CeAD.