Abnormal ambulatory electrocardiographic findings in patients with the Marfan syndrome

Unique Features of Cardiovascular Involvement and Progression in Children with Marfan Syndrome Justify Dedicated Multidisciplinary Care

Marfan syndrome (MIM: # 154700; MFS) is an autosomal dominant disease representing the most common form of heritable connective tissue disorder. The condition presents variable multiorgan expression, typically involving a triad of cardiovascular, eye, and skeletal manifestations. Other multisystemic features are often underdiagnosed. Moreover, the disease is characterized by age related penetrance. Diagnosis and management of MFS in the adult population are well-described in literature. Few studies are focused on MFS in the pediatric population, making the clinical approach (cardiac and multiorgan) to these cases challenging both in terms of diagnosis and serial follow-up. In this review, we provide an overview of MFS manifestations in children, with extensive revision of major organ involvement (cardiovascular ocular and skeletal). We attempt to shed light on minor aspects of MFS that can have a significant progressive impact on the health of affected children. MFS is an example of a syndrome where an early personalized approach to address a dynamic, genetically determined condition can make a difference in outcome. Applying an early multidisciplinary clinical approach to MFS cases can prevent acute and chronic complications, offer tailored management, and improve the quality of life of patients.

Association of Mitral Annular Disjunction With Cardiovascular Outcomes Among Patients With Marfan Syndrome

Importance

Mitral annular disjunction (MAD) has received particular interest in patients with mitral valve prolapse, ventricular tachycardia, and sudden cardiac death. The clinical significance of MAD for patients with Marfan syndrome (MFS) remains largely unexplored.

Objective

To define the prevalence of MAD and examine its association with cardiovascular outcomes and arrhythmia among patients with MFS.

Design, Setting, and Participants

This retrospective, single-center cohort study included 142 patients with a diagnosis of MFS based on the revised Ghent criteria and a confirmed (likely) pathogenic variant in the FBN1 gene who underwent regular follow-up between January 1, 2004, and December 31, 2019.

Main Outcomes and Measures

The presence of MAD was assessed by echocardiography, and the extent of MAD was categorized in tertiles. Patients also underwent resting electrocardiography and 24-hour Holter monitoring. Outcomes included aortic events (aortic dissection or prophylactic aortic surgery), arrhythmic events (defined as sustained ventricular tachycardia or sudden cardiac death), and mitral valve surgery.

Results

A total of 142 patients (72 female patients [51%]; median age at first examination, 25 years [range, 2-64 years]) were evaluated. Forty-eight patients (34%) had MAD. Patients with MAD had larger aortic root z scores than patients without MAD (4.1 [interquartile range, 2.8-5.7] vs 3.0 [interquartile range, 1.8-4.0]; P < .001) and more often had mitral valve prolapse (34 of 48 [71%] vs 14 of 94 [15%]; P < .001), ventricular ectopy (14 of 33 [42%] vs 15 of 70 [21%]; P = .03), and nonsustained ventricular tachycardia (13 of 33 [39%] vs 12 of 70 [17%]; P = .01). During follow-up, aortic events occurred at similar rates among patients with vs without MAD (15 of 43 [35%] vs 21 of 84 [25%]; P = .24), but patients in the upper MAD tertile (>10 mm) showed a higher occurrence of aortic events compared with patients with MAD of 10 mm or smaller (9 of 15 [60%] vs 6 of 28 [21%]; P = .01). Patients with arrhythmic events (n = 5) and patients requiring mitral valve surgery (n = 7) were observed exclusively in the group displaying MAD.

Conclusions and Relevance

This study suggests that MAD among patients with MFS is associated with the occurrence of arrhythmic events, a higher need for mitral valve intervention, and, among patients with extensive MAD, more aortic events. Cardiac imaging for patients with MFS should consider the assessment of MAD as a potential marker for adverse outcomes.

Cardiomyopathy in Genetic Aortic Diseases

Genetic aortic diseases are a group of illnesses characterized by aortic aneurysms or dissection in the presence of an underlying genetic defect. They are part of the broader spectrum of heritable thoracic aortic disease, which also includes those cases of aortic aneurysm or dissection with a positive family history but in whom no genetic cause is identified. Aortic disease in these conditions is a major cause of mortality, justifying clinical and scientific emphasis on the aorta. Aortic valve disease and atrioventricular valve abnormalities are known as important additional manifestations that require careful follow-up and management. The archetype of genetic aortic disease is Marfan syndrome, caused by pathogenic variants in the Fibrillin-1 gene. Given the presence of fibrillin-1 microfibers in the myocardium, myocardial dysfunction and associated arrhythmia are conceivable and have been shown to contribute to morbidity and mortality in patients with Marfan syndrome. In this review, we will discuss data on myocardial disease from human studies as well as insights obtained from the study of mouse models of Marfan syndrome. We will elaborate on the various phenotypic presentations in childhood and in adults and on the topic of arrhythmia. We will also briefly discuss the limited data available on other genetic forms of aortic disease.

Myocardial disease and ventricular arrhythmia in Marfan syndrome: a prospective study

Background

Aortic root dilatation and—dissection and mitral valve prolapse are established cardiovascular manifestations in Marfan syndrome (MFS). Heart failure and arrhythmic sudden cardiac death have emerged as additional causes of morbidity and mortality.

Methods

To characterize myocardial dysfunction and arrhythmia in MFS we conducted a prospective longitudinal case–control study including 86 patients with MFS (55.8% women, mean age 36.3 yr—range 13–70 yr–) and 40 age—and sex-matched healthy controls. Cardiac ultrasound, resting and ambulatory ECG (AECG) and NT-proBNP measurements were performed in all subjects at baseline. Additionally, patients with MFS underwent 2 extra evaluations during 30 ± 7 months follow-up. To study primary versus secondary myocardial involvement, patients with MFS were divided in 2 groups: without previous surgery and normal/mild valvular function (MFS-1; N = 55) and with previous surgery or valvular dysfunction (MFS-2; N = 31).

Results

Compared to controls, patients in MFS-1 showed mild myocardial disease reflected in a larger left ventricular end-diastolic diameter (LVEDD), lower TAPSE and higher amount of (supra) ventricular extrasystoles [(S)VES]. Patients in MFS-2 were more severely affected. Seven patients (five in MFS-2) presented decreased LV ejection fraction. Twenty patients (twelve in MFS-2) had non-sustained ventricular tachycardia (NSVT) in at least one AECG. Larger LVEDD and higher amount of VES were independently associated with NSVT.

Conclusion

Our study shows mild but significant myocardial involvement in patients with MFS. Patients with previous surgery or valvular dysfunction are more severely affected. Evaluation of myocardial function with echocardiography and AECG should be considered in all patients with MFS, especially in those with valvular disease and a history of cardiac surgery.

Myocardial Function, Heart Failure and Arrhythmia in Marfan Syndrome: A Systematic Literature Review

Marfan syndrome (MFS) is a heritable systemic connective tissue disease with important cardiovascular involvement, including aortic root dilatation and mitral valve prolapse. Life expectancy in patients with MFS is mainly determined by cardiovascular complications, among which aortic dissection or rupture are most dreaded. In recent years, heart failure and ventricular arrhythmia have drawn attention as extra-aortic cardiovascular manifestations and as additional reported causes of death. Imaging studies have provided data supporting a primary myocardial impairment in the absence of valvular disease or cardiovascular surgery, while studies using ambulatory ECG have demonstrated an increased susceptibility to ventricular arrhythmia. In this paper, current literature was reviewed in order to provide insights in characteristics, pathophysiology and evolution of myocardial function, heart failure and ventricular arrhythmia in MFS.

Spontaneous Right Ventricular Pseudoaneurysms and Increased Arrhythmogenicity in a Mouse Model of Marfan Syndrome

Patients with Marfan syndrome (MFS), a connective tissue disorder caused by pathogenic variants in the gene encoding the extracellular matrix protein fibrillin-1, have an increased prevalence of primary cardiomyopathy, arrhythmias, and sudden cardiac death. We have performed an in-depth in vivo and ex vivo study of the cardiac phenotype of Fbn1mgR/mgR mice, an established mouse model of MFS with a severely reduced expression of fibrillin-1. Using ultrasound measurements, we confirmed the presence of aortic dilatation and observed cardiac diastolic dysfunction in male Fbn1mgR/mgR mice. Upon post-mortem examination, we discovered that the mutant mice consistently presented myocardial lesions at the level of the right ventricular free wall, which we characterized as spontaneous pseudoaneurysms. Histological investigation demonstrated a decrease in myocardial compaction in the MFS mouse model. Furthermore, continuous 24 h electrocardiographic analysis showed a decreased heart rate variability and an increased prevalence of extrasystolic arrhythmic events in Fbn1mgR/mgR mice compared to wild-type littermates. Taken together, in this paper we document a previously unreported cardiac phenotype in the Fbn1mgR/mgR MFS mouse model and provide a detailed characterization of the cardiac dysfunction and rhythm disorders which are caused by fibrillin-1 deficiency. These findings highlight the wide spectrum of cardiac manifestations of MFS, which might have implications for patient care.

Marfan syndrome revisited: From genetics to the clinic

Marfan syndrome is an autosomal dominant connective tissue disease with an estimated incidence of 1 in 5000 individuals. In 90% of cases it is caused by mutations in the gene for fibrillin-1, the main constituent of extracellular microfibrils. Studies on animal models of Marfan syndrome have revealed that fibrillin-1 mutations interfere with local TGF-β signaling, in addition to impairing tissue integrity. The cardinal features involve the cardiovascular, ocular and skeletal systems. The diagnosis of Marfan syndrome is made according to the revised Ghent nosology. Early identification and appropriate management are critical for patients with Marfan syndrome, who are prone to the life-threatening cardiovascular complications of aortic aneurysms and aortic dissection. The standard treatment includes prophylactic beta-blockers in order to slow down dilation of the ascending aorta, and prophylactic aortic surgery. The success of current medical and surgical treatment of aortic disease in Marfan syndrome has substantially improved mean life expectancy, extending it above 72 years. This review aims to provide an overview of this hereditary disorder.

Differences in Cardiovascular Manifestation of Marfan Syndrome Between Children and Adults

Marfan syndrome (MFS) is a connective tissue disorder characterized by a broad range of clinical manifestations. Cardiovascular involvement is the most life-threatening aspect of the syndrome. Although abnormalities within the cardiovascular system in adults are well documented, there is still a paucity of data regarding manifestation of MFS in childhood. The aim of the study was to compare cardiovascular manifestation of MFS between children and adults. The study population consisted of 236 patients (144 children and 92 adults), who were referred to our department with suspicion of MFS. All patients underwent complete clinical evaluation in order to confirm the diagnosis of MFS according to the modified Ghent criteria. MFS was diagnosed in 101 (44 children and 57 adults) out of the 236 patients. The other patients were diagnosed with Ehlers-Danlos syndrome, Loeys-Dietz syndrome, MASS phenotype, ectopia lentis syndrome, marfanoid habitus and other rare syndromes. The most common cardiovascular abnormality was aortic root dilatation (81.19% of patients). It was found that both adults and children had similar high rates of aortic root dilatation. Similarly, there was no significant difference with regard to the prevalence of aortic valve regurgitation and mitral valve prolapse among children and adults. These findings equivocally indicate that the aforementioned abnormalities develop in early childhood, therefore, they may be used in the early identification of patients with MFS. Other assessed abnormalities, which included mitral valve regurgitation, pulmonary artery dilation, aneurysms of aortic arch, descending thoracic aorta and abdominal aorta were found mostly in adults, and thus, are of less use in the early detection of MFS.

High prevalence of ventricular repolarization abnormalities in people carrying TGFβR2 mutations

Mutations in the TGFβR2 gene have been associated with a life threatening risk of aortic dissection but no arrhythmic death has been previously reported. Two young females carrying a TGFβR2 mutation, initially diagnosed as Marfan syndrome or Loeys Dietz syndrome, presented sudden death with autopsy ruling out dissection. The ECGs of the 2 Sudden Cardiac Deaths revealed profound ventricular repolarization abnormalities with a sinusoidal T-U morphology associated with normal left ventricular ejection fraction. These data strongly suggest sudden cardiac arrhythmic deaths and prompted us to systematically study the repolarization pattern in the patients with TGFβR2 mutations. ECG findings from 58 mutation carriers patients (TGFβR2 group) were compared with those of 46 non-affected first degree relatives (control group). TGFβR2 mutation was associated with ventricular repolarization abnormalities in 47% of patients (p < 0.001 vs. controls), including a 19.6 ms (95%CI 8.7; 30.5) QTc interval prolongation compared to the non-affected first degree relatives (p < 0.001), higher prevalence of abnormal U waves (16% vs. 2%), and sinusoidal T-U morphology (10% vs. 0%). TGFβR2 mutations can be associated with abnormal ventricular repolarization pattern, longer QT interval than non-carrier relatives and an increased risk for sudden death.

Utility of serial 12-lead electrocardiograms in children with Marfan syndrome

OBJECTIVES

The goal of this study was to assess the utility of serial electrocardiograms in routine follow-up of paediatric Marfan patients.

METHODS

Children ⩽18 years who met the revised Ghent criteria for Marfan syndrome and received a 12-lead electrocardiogram and echocardiogram within a 3-month period were included. Controls were matched by age, body surface area, gender, race, and ethnicity, and consisted of patients assessed in clinic with a normal cardiac evaluation. Demographic, clinical, echocardiographic, and electrocardiographic data were collected.

RESULTS

A total of 45 Marfan patients (10.8 [2.4-17.1] years) and 37 controls (12.8 [1.3-17.1] years) were included. Left atrial enlargement and left ventricular hypertrophy were more frequently present on 12-lead electrocardiogram of Marfan patients compared with controls (12 (27%) versus 0 (0%), p<0.001; and 8 (18%) versus 0 (0%), p=0.008, respectively); however, only two patients with left atrial enlargement on 12-lead electrocardiogram were confirmed to have left atrial enlargement by echocardiogram, and one patient had mild left ventricular hypertrophy by echocardiogram, not appreciated on 12-lead electrocardiogram. QTc interval was longer in Marfan patients compared with controls (427±16 versus 417±22 ms, p=0.03), with four Marfan patients demonstrating borderline prolonged QTc intervals for gender.

CONCLUSIONS

While Marfan patients exhibited a higher frequency of left atrial enlargement and left ventricular hypertrophy on 12-lead electrocardiograms compared with controls, these findings were not supported by echocardiography. Serial 12-lead electrocardiograms in routine follow-up of asymptomatic paediatric Marfan patients may be more appropriate for a subgroup of Marfan patients only, specifically those with prolonged QTc interval at their baseline visit.

Anomalous Coronary Artery Origin in a Young Patient with Marfan Syndrome

Marfan syndrome is an autosomal dominant genetic disorder that affects connective tissue and is caused by mutations in the fibrillin 1 gene present at chromosome 15. Aortic aneurysm is its main complication, and along the dilation of the aorta root and its descending portion (60–100%), with secondary aortic insufficiency, it increases risk of acute aortic dissection and death. Coronary artery anomalies affect between 0.3% and 1.6% of the general population and are the second leading cause of sudden death in young adults, especially if the anomalous coronary passes through aorta and pulmonary artery. The anomalous origin of the left main coronary artery in the right Valsalva sinus has a prevalence of 0.02%–0.05% and is commonly related to other congenital cardiac anomalies, such as transposition of great vessels, coronary fistulas, bicuspid aortic valve, and tetralogy of Fallot. Its association with Marfan syndrome is not known, and there is no previous report in the literature. We describe here a case of a female with Marfan syndrome diagnosed with symptomatic anomalous origin of the left coronary artery in the right Valsalva sinus.

Cardiovascular Benefits of Moderate Exercise Training in Marfan Syndrome: Insights From an Animal Model

BACKGROUND

Marfan syndrome (MF) leads to aortic root dilatation and a predisposition to aortic dissection, mitral valve prolapse, and primary and secondary cardiomyopathy. Overall, regular physical exercise is recommended for a healthy lifestyle, but dynamic sports are strongly discouraged in MF patients. Nonetheless, evidence supporting this recommendation is lacking. Therefore, we studied the role of long-term dynamic exercise of moderate intensity on the MF cardiovascular phenotype.

METHODS AND RESULTS

In a transgenic mouse model of MF (Fbn1^C1039G/+), 4-month-old wild-type and MF mice were subjected to training on a treadmill for 5 months; sedentary littermates served as controls for each group. Aortic and cardiac remodeling was assessed by echocardiography and histology. The 4-month-old MF mice showed aortic root dilatation, elastic lamina rupture, and tunica media fibrosis, as well as cardiac hypertrophy, left ventricular fibrosis, and intramyocardial vessel remodeling. Over the 5-month experimental period, aortic root dilation rate was significantly greater in the sedentary MF group, compared with the wild-type group (∆mm, 0.27±0.07 versus 0.13±0.02, respectively). Exercise significantly blunted the aortic root dilation rate in MF mice compared with sedentary MF littermates (∆mm, 0.10±0.04 versus 0.27±0.07, respectively). However, these 2 groups were indistinguishable by aortic root stiffness, tunica media fibrosis, and elastic lamina ruptures. In MF mice, exercise also produced cardiac hypertrophy regression without changes in left ventricular fibrosis.

CONCLUSIONS

Our results in a transgenic mouse model of MF indicate that moderate dynamic exercise mitigates the progression of the MF cardiovascular phenotype.

Marfan syndrome and cardiovascular complications: results of a family investigation

Background

Cardiovascular complications in Marfan syndrome (MFS) make all its seriousness. Taking as a basis the Ghent criteria, we conducted a family screening from an index case. The objective was to describe the clinical characteristics of MFS anomalies and to detect cardiovascular complications in our patients.

Case presentation

Six subjects were evaluated. Patients had to be in the same uterine siblings of the index case or be a descendant. The objective was to search for MFS based on the diagnostic criteria of Ghent and, subsequently, detecting cardiovascular damage. The average age was 24 years. The examination revealed three cases of sudden death in a context of chest pain. Five subjects had systemic involvement with a score ≥ 7 that allowed to the diagnosis of MFS. Two patients had simultaneously ectopia lentis and myopia. In terms of cardiovascular damage, there were three cases of dilatation of the aortic root, two cases of aortic dissection of Stanford’s type A with severe aortic regurgitation in one case and moderate in the other. There were three patients with moderate mitral regurgitation with a case by valve prolapse.

Conclusion

The family screening is crucial in Marfan syndrome. It revealed serious cardiovascular complications including sudden death and aortic dissection.

The role of the multidisciplinary health care team in the management of patients with Marfan syndrome

Marfan syndrome (MFS) is a rare, severe, chronic, life-threatening disease with multiorgan involvement that requires optimal multidisciplinary care to normalize both prognosis and quality of life. In this article, each key team member of all the medical disciplines of a multidisciplinary health care team at the Hamburg Marfan center gives a personal account of his or her contribution in the management of patients with MFS. The authors show how, with the support of health care managers, key team members organize themselves in an organizational structure to create a common meaning, to maximize therapeutic success for patients with MFS. First, we show how the initiative and collaboration of patient representatives, scientists, and physicians resulted in the foundation of Marfan centers, initially in the US and later in Germany, and how and why such centers evolved over time. Then, we elucidate the three main structural elements; a team of coordinators, core disciplines, and auxiliary disciplines of health care. Moreover, we explain how a multidisciplinary health care team integrates into many other health care structures of a university medical center, including external quality assurance; quality management system; clinical risk management; center for rare diseases; aorta center; health care teams for pregnancy, for neonates, and for rehabilitation; and in structures for patient centeredness. We provide accounts of medical goals and standards for each core discipline, including pediatricians, pediatric cardiologists, cardiologists, human geneticists, heart surgeons, vascular surgeons, vascular interventionists, orthopedic surgeons, ophthalmologists, and nurses; and of auxiliary disciplines including forensic pathologists, radiologists, rhythmologists, pulmonologists, sleep specialists, orthodontists, dentists, neurologists, obstetric surgeons, psychiatrist/psychologist, and rehabilitation specialists. We conclude that a multidisciplinary health care team is a means to maximize therapeutic success.

Abnormal heart rate recovery and deficient chronotropic response after submaximal exercise in young Marfan syndrome patients

BACKGROUND

Marfan syndrome patients present important cardiac structural changes, ventricular dysfunction, and electrocardiographic changes. An abnormal heart rate response during or after exercise is an independent predictor of mortality and autonomic dysfunction. The aim of the present study was to compare heart rate recovery and chronotropic response obtained by cardiac reserve in patients with Marfan syndrome subjected to submaximal exercise.

METHODS

A total of 12 patients on β-blocker therapy and 13 off β-blocker therapy were compared with 12 healthy controls. They were subjected to submaximal exercise with lactate measurements. The heart rate recovery was obtained in the first minute of recovery and corrected for cardiac reserve and peak lactate concentration.

RESULTS

Peak heart rate (141±16 versus 155±17 versus 174±8 bpm; p=0.001), heart rate reserve (58.7±9.4 versus 67.6±14.3 versus 82.6±4.8 bpm; p=0.001), heart rate recovery (22±6 versus 22±8 versus 34±9 bpm; p=0.001), and heart rate recovery/lactate (3±1 versus 3±1 versus 5±1 bpm/mmol/L; p=0.003) were different between Marfan groups and controls, respectively. All the patients with Marfan syndrome had heart rate recovery values below the mean observed in the control group. The absolute values of heart rate recovery were strongly correlated with the heart rate reserve (r=0.76; p=0.001).

CONCLUSION

Marfan syndrome patients have reduced heart rate recovery and chronotropic deficit after submaximal exercise, and the chronotropic deficit is a strong determinant of heart rate recovery. These changes are suggestive of autonomic dysfunction.

Cardiovascular Management of Adults with Marfan Syndrome

Marfan syndrome (MFS) is a disease in which connective tissue becomes weak secondary to fibrillin-1 mutations, resulting in aortic dilatation, aneurysm formation, aortic dissection, aortic regurgitation and mitral valve prolapse. This autosomal dominantly inherited condition, which was first reported in 1895 and was more fully described in 1931, is characterised by abnormal Fibrillin-1 protein (FBN1) (discovered in 1990), which is encoded by the FBN1 gene (reported in 1991). In the 1970s, the life expectancy of people with MFS was 40-50 years, mainly due to increased risk of aortic dissection or heart failure from aortic or mitral regurgitation. However, due to advances in medical and surgical therapy, life expectancy has improved dramatically and is now comparable to that of the general population. We discuss the cardiac manifestations of MFS, the incidence of arrhythmia in this population, the standard of medical care for arrhythmia and valve insufficiency, and a new use of preventive medication to preserve the integrity of the aortic wall in patients with MFS.

Perspectives on the revised Ghent criteria for the diagnosis of Marfan syndrome

Three international nosologies have been proposed for the diagnosis of Marfan syndrome (MFS): the Berlin nosology in 1988; the Ghent nosology in 1996 (Ghent-1); and the revised Ghent nosology in 2010 (Ghent-2). We reviewed the literature and discussed the challenges and concepts of diagnosing MFS in adults. Ghent-1 proposed more stringent clinical criteria, which led to the confirmation of MFS in only 32%–53% of patients formerly diagnosed with MFS according to the Berlin nosology. Conversely, both the Ghent-1 and Ghent-2 nosologies diagnosed MFS, and both yielded similar frequencies of MFS in persons with a causative FBN1 mutation (90% for Ghent-1 versus 92% for Ghent-2) and in persons not having a causative FBN1 mutation (15% versus 13%). Quality criteria for diagnostic methods include objectivity, reliability, and validity. However, the nosology-based diagnosis of MFS lacks a diagnostic reference standard and, hence, quality criteria such as sensitivity, specificity, or accuracy cannot be assessed. Medical utility of diagnosis implies congruency with the historical criteria of MFS, as well as with information about the etiology, pathogenesis, diagnostic triggers, prognostic triggers, and potential complications of MFS. In addition, social and psychological utilities of diagnostic criteria include acceptance by patients, patient organizations, clinicians and scientists, practicability, costs, and the reduction of anxiety. Since the utility of a diagnosis or exclusion of MFS is context-dependent, prioritization of utilities is a strategic decision in the process of nosology development. Screening tests for MFS should be used to identify persons with MFS. To confirm the diagnosis of MFS, Ghent-1 and Ghent-2 perform similarly, but Ghent-2 is easier to use. To maximize the utility of the diagnostic criteria of MFS, a fair and transparent process of nosology development is essential.

Heart rate turbulence and deceleration capacity for risk prediction of serious arrhythmic events in Marfan syndrome

OBJECTIVE

Marfan syndrome (MFS) is associated with a substantial risk for ventricular arrhythmia and sudden cardiac death (SCD). We used heart rate turbulence (HRT) and deceleration capacity (DC), to evaluate the risk stratification for these patients.

METHODS

We enrolled 102 patients [45 male (44.1 %), age 40.5 ± 14.6 years] with MFS. Blood samples were obtained to determine N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Transthoracic echocardiography studies were conducted to evaluate heart function parameters and a 24-h holter ECG was performed. An analysis of two HRT parameters, turbulence onset (TO) and turbulence slope (TS), and DC was performed. Therefore, optimal cut-off values were calculated. Primary endpoint was the combination of SCD, ventricular arrhythmia and arrhythmogenic syncope. Secondary endpoint was total mortality.

RESULTS

During a follow-up of 1145 ± 491 days, 12 (11.7 %) patients reached the primary and 8 (7.8 %) patients the secondary endpoint. Patients reaching the primary were significantly older, had a higher burden of premature ventricular complexes and NT-proBNP levels and lower values of LVEF, DC and HRT TS. Multivariate analysis identified NT-proBNP (HR 1.25, 95 % CI 1.01-1.56, p = .04) and the abnormal HRT (abnormal TS and/or TO (HR 7.04, 95 % CI 1.07-46.27, p = .04) as independent risk predictor of arrhythmogenic events.

CONCLUSION

Patients with Marfan syndrome are at risk for severe ventricular arrhythmias and SCD. Abnormal HRT parameters and NT-proBNP values are independent risk factors for arrhythmogenic events and SCD. The assessment of these tools may help predicting SCD patients with MFS.

Sudden cardiac death in the young: the bogeyman

Sudden cardiac death in the young is a relatively uncommon but marked event usually related to congenital diseases or anomalies. Despite the prevalence of each condition being variable, most common causes include primary myocardial diseases and arrhythmic disorder, frequently with inheritance pattern. Sudden cardiac death is usually preceded by symptoms, thus making personal and family history fundamental for its prevention. Nevertheless, in more than 50% of cases, sudden cardiac death is the first manifestation of the disease. In this review, we describe the different causes of sudden cardiac death, their incidence, and currently used preventive strategies.

Observational cohort study of ventricular arrhythmia in adults with Marfan syndrome caused by FBN1 mutations

BACKGROUND

Marfan syndrome is associated with ventricular arrhythmia but risk factors including FBN1 mutation characteristics require elucidation.

METHODS AND RESULTS

We performed an observational cohort study of 80 consecutive adults (30 men, 50 women aged 42±15 years) with Marfan syndrome caused by FBN1 mutations. We assessed ventricular arrhythmia on baseline ambulatory electrocardiography as >10 premature ventricular complexes per hour (>10 PVC/h), as ventricular couplets (Couplet), or as non-sustained ventricular tachycardia (nsVT), and during 31±18 months of follow-up as ventricular tachycardia (VT) events (VTE) such as sudden cardiac death (SCD), and sustained ventricular tachycardia (sVT). We identified >10 PVC/h in 28 (35%), Couplet/nsVT in 32 (40%), and VTE in 6 patients (8%), including 3 with SCD (4%). PVC>10/h, Couplet/nsVT, and VTE exhibited increased N-terminal pro-brain natriuretic peptide serum levels(P<.001). All arrhythmias related to increased NT-proBNP (P<.001), where PVC>10/h and Couplet/nsVT also related to increased indexed end-systolic LV diameters (P = .024 and P = .020), to moderate mitral valve regurgitation (P = .018 and P = .003), and to prolonged QTc intervals (P = .001 and P = .006), respectively. Moreover, VTE related to mutations in exons 24-32 (P = .021). Kaplan-Meier analysis corroborated an association of VTE with increased NT-proBNP (P<.001) and with mutations in exons 24-32 (P<.001).

CONCLUSIONS

Marfan syndrome with causative FBN1 mutations is associated with an increased risk for arrhythmia, and affected persons may require life-long monitoring. Ventricular arrhythmia on electrocardiography, signs of myocardial dysfunction and mutations in exons 24-32 may be risk factors of VTE.

Prospective risk stratification of sudden cardiac death in Marfan's syndrome

BACKGROUND

Marfan syndrome (MFS) is a variable, autosomal-dominant disorder of the connective tissue. In MFS serious ventricular arrhythmias and sudden cardiac death (SCD) can occur. The aim of this prospective study was to reveal underlying risk factors and to prospectively investigate the association between MFS and SCD in a long-term follow-up.

METHODS

77 patients with MFS were included. At baseline serum N-terminal pro-brain natriuretic peptide (NT-proBNP), transthoracic echocardiogram, 12-lead resting ECG, signal-averaged ECG (SAECG) and a 24-h Holter ECG with time- and frequency domain analyses were performed. The primary composite endpoint was defined as SCD, ventricular tachycardia (VT), ventricular fibrillation (VF) or arrhythmogenic syncope.

RESULTS

The median follow-up (FU) time was 868 days. Among all risk stratification parameters, NT-proBNP remained the exclusive predictor (hazard ratio [HR]: 2.34, 95% confidence interval [CI]: 1.1 to 4.62, p=0.01) for the composite endpoint. With an optimal cut-off point at 214.3 pg/ml NT-proBNP predicted the composite primary endpoint accurately (AUC 0.936, p=0.00046, sensitivity 100%, specificity 79.0%). During FU, seven patients of Group 2 (NT-proBNP ≥ 214.3 pg/ml) reached the composite endpoint and 2 of these patients died due to SCD. In five patients, sustained VT was documented. All patients with a NT-proBNP<214.3 pg/ml (Group 1) experienced no events. Group 2 patients had a significantly higher risk of experiencing the composite endpoint (logrank-test, p<0.001).

CONCLUSIONS

In contrast to non-invasive electrocardiographic parameter, NT-proBNP independently predicts adverse arrhythmogenic events in patients with MFS.

Single gene disorders of the aortic wall

Genetic diseases that affect the vasculature primarily affect the aortic root and ascending aorta. These conditions lead to aortic root dilatation, which, if not treated, will result in dissection and death. Often, aortic disease is just one manifestation of a syndrome with diverse findings. Some of these diseases were described over 100 years ago based on physical manifestations, and their causative genes are among the first described Mendelian causes of cardiovascular disease. Within the pediatric and young adult population, there are over 15 causes of ascending aortic disease. Previously, these diverse diseases, along with their histopathology, have been extensively characterized. Most genetic causes of root aneurysm are extremely rare. Amongst these, five diseases are relatively common with known genetic mutations for which pathologists should be familiar. These are Marfan syndrome, vascular Ehlers-Danlos syndrome, Loeys-Dietz syndrome, Turner syndrome, and familial thoracic aneurysm and dissection. This review will focus on these important causes of genetic aortic disease. The aim is to briefly describe the historical record and physical manifestations and then focus on cardiovascular complications, the causative genes, and current research into these entities.

Cardiovascular effects of medications for the treatment of attention-deficit hyperactivity disorder: what is known and how should it influence prescribing in children?

The effective medications currently marketed for attention-deficit hyperactivity disorder (ADHD) have central and peripheral catecholaminergic effects that have been shown to result in statistically significant increases in heart rate and blood pressure. The impact of these medications on serious cardiovascular events in healthy children is unknown, but serious cardiovascular events related to ADHD medications are considered rare. However, children with cardiac pathology may be at greater risk given that increased sympathetic tone has been reported as a causal factor in generating ventricular arrhythmias in adults with coronary artery disease, and physical exercise has been consistently reported as a trigger for increased risk of sudden cardiac death in athletes with underlying cardiovascular disease. ADHD has high co-morbidity with anxiety and depression. These conditions in adults have been reported to have their own cardiovascular risks that may be compounded by interactions resulting from combined pharmacotherapeutic treatments; this interaction has not been evaluated in children. High rates of ADHD reported in subjects with cardiac pathology, as well as in patients with genetic disorders associated with cardiovascular pathology, also suggest that the prevalence of cardiac pathology in ADHD subjects may be greater than that in the general population. Currently, the US FDA and Health Canada require warnings on prescription labeling information for ADHD medications, suggesting that these medications should not generally be used in children or adults with 'known' serious cardiac pathology. Family history, medical history, and physical examination have very low sensitivity for identifying serious cardiac pathology, but this can be markedly enhanced in many instances with the use of electrocardiography, which has high specificity and sensitivity. Identifying and managing underlying cardiovascular pathology may not eliminate the risk of serious cardiovascular events but may increase the safety of using medication frequently required for effective management of ADHD. When the very common and serious consequences from untreated ADHD are also considered in the assessment of risks and benefits, even in the presence of cardiac pathology, it seems that the prescribing of ADHD medications in children should remain unchanged.

The Marfan syndrome: implications for athletes and their echocardiographic assessment

Sudden death of competitive athletes is rare. These deaths challenge the perception that trained athletes represent the healthiest segment of modern society. The increasing frequency of such reported deaths worldwide and the visibility of the issue is underlined by the high-profile nature of each case. The majority of these deaths have been due to a variety of undiagnosed cardiovascular diseases. Marfan syndrome is a heritable disorder of the connective tissue that can hold life threatening consequences, especially for the athletic population. This paper will aim to review cardiovascular pathophysiology and assessment in relation to Marfan syndrome with particular reference to echocardiography and the athletic population.

Catheter ablation for atrial fibrillation in patients with the Marfan and Marfan-like syndromes

Patients with the Marfan syndrome may pose a difficult challenge for catheter-based interventions due to frequent coexisting valve disease, potential delay in vascular healing and repair, and intra-atrial scar from prior cardiac surgery. We report a case series of four patients with Marfan or Marfan-like syndromes who underwent ablation for drug-refractory atrial fibrillation. Ultimately three of four patients remained in sinus rhythm, however most patients required multiple ablative attempts and long-term atrial flutter was common. Nonetheless, peri-procedural complications were minimal despite the connective tissue disorder and prosthetic valves in three of four patients. In conclusion, catheter ablation of AF in patients with Marfan syndrome is a viable option in those individuals refractory to conventional therapy.

Ageing in Marfan syndrome

AIMS

Marfan syndrome (MFS) is a dominantly inherited connective tissue disorder caused by mutations in the fibrillin-1 gene. Past research has focused on younger patients as lifespan was known to be significantly reduced. This study aims to describe the complications, including those affecting the eyes, heart and musculoskeletal system, faced by older survivors.

METHODS

All 2500 patient records from the National Marfan Syndrome Clinical Database were searched for suitable participants aged 50 or older. One hundred and fifty-six questionnaires were posted to patients with MFS. These patients were sent a detailed questionnaire regarding medical aspects of their disease. Those included in the study were sent questionnaires for spouses and friends (not blood relatives) to complete, to provide control data. Other age- and sex-matched controls were recruited locally.

RESULTS

Sixty questionnaires from patients with MFS (35%) were returned and eligible for inclusion in the study, comprising 28 female patients and 32 male patients with a median age of 57. We recruited 56 eligible controls. Our results revealed that patients over 50 years of age with MFS may be at a higher risk than previously assumed for retinal detachment (reported by 24% of our respondents) and cardiovascular abnormalities (42% have had past aortic surgery; 53% report palpitation). Lesser known complications were also reported, including cataract (reported by 27%).

CONCLUSIONS

Medical practitioners should be aware of the range of complications that can occur in patients with MFS in addition to the normal ageing process. Health problems in MFS patients over 50 may require investigation and specific therapy earlier than in the normal ageing population, because of the degenerative nature of this genetic condition.

Initial description of radiofrequency catheter ablation as treatment for atrial flutter in Marfan's syndrome: a case report and literature review

Marfan's syndrome is a common connective tissue disease with different musculoskeletal, ophthalmic and cardiac manifestations. Marfan's patients carry increased risk for cardiac arrhythmias. Only three cases of atrial flutter in Marfan's patients are described in the literature. We report a fourth case of a young Marfan's patient who presents with typical atrial flutter after motor vehicle accident. After electrical cardioversion, sinus rhythm was restored but he had recurrent atrial flutter on follow up. The patient then underwent electrophysiological study and successful radiofrequency catheter ablation of the flutter circuit. Since discharge, the patient has had no documented arrhythmias on follow up.

Marfan's syndrome and the heart

In recent years, there have been many advances in the treatment of cardiac disease in children with Marfan's syndrome. Early diagnosis, meticulous echocardiographic follow-up and multidisciplinary assessment are essential. Medical treatment with beta-blockers is probably helpful in most children with aortic root dilatation. Research on TGFbeta signalling and the potential treatment role of TGFbeta antagonists may lead to exciting new treatments, but the results of clinical trials are awaited. In managing the cardiovascular complications of Marfan's syndrome, the paediatrician has to walk a difficult path. On the one hand, restrictive lifestyle advice and drugs may need to be prescribed, often in the context of a family history of major surgery or even sudden death. On the other hand, it is essential to encourage the often asymptomatic child to develop and mature as normally as possible.

Marfan's syndrome

Marfan's syndrome is a systemic disorder of connective tissue caused by mutations in the extracellular matrix protein fibrillin 1. Cardinal manifestations include proximal aortic aneurysm, dislocation of the ocular lens, and long-bone overgrowth. Important advances have been made in the diagnosis and medical and surgical care of affected individuals, yet substantial morbidity and premature mortality remain associated with this disorder. Progress has been made with genetically defined mouse models to elucidate the pathogenetic sequence that is initiated by fibrillin-1 deficiency. The new understanding is that many aspects of the disease are caused by altered regulation of transforming growth factor beta (TGFbeta), a family of cytokines that affect cellular performance, highlighting the potential therapeutic application of TGFbeta antagonists. Insights derived from studying this mendelian disorder are anticipated to have relevance for more common and non-syndromic presentations of selected aspects of the Marfan phenotype.

Long-term outcome in patients with Marfan syndrome: is aortic dissection the only cause of sudden death?

OBJECTIVES

We sought to assess outcomes in a series of young patients with Marfan syndrome and to define the prevalence of ventricular arrhythmias in this patient population.

BACKGROUND

While sudden death is a well-recognized outcome in Marfan syndrome, ventricular arrhythmias are not well described.

METHODS

Patients were followed with echocardiography, electrocardiography, and ambulatory electrocardiography. The prevalence and associated factors for ventricular dysrhythmias were defined.

RESULTS

Seventy patients with Marfan syndrome diagnosed at birth to 52 years were followed for a period of up to 24 years. All patients had cardiovascular involvement and were started on medical therapy. No patient died from aortic dissection, while 4% died from arrhythmias. Ventricular arrhythmias were present in 21% and were associated with increased left ventricular size, mitral valve prolapse, and abnormalities of repolarization.

CONCLUSIONS

Cardiac complications are rare in young patients with Marfan syndrome receiving medical therapy and close clinical follow-up. Sudden death still occurs, and appears more common in patients with a dilated left ventricle. Left ventricular dilation may predispose to alterations of repolarization and fatal ventricular arrhythmias.