Fabry disease in W162C mutation: a case report of two patients and a review of literature

BACKGROUND

Fabry disease is a multisystemic disorder characterized by deposition of globotriaosylceramide (Gb3) and its deacylated form in multiple organs, sometimes localized in specific systems such as the nervous or cardiovascular system. As disease-modifying therapies are now available, early diagnosis is paramount to improving life quality and clinical outcomes. Despite the widespread use of non-invasive techniques for assessing organ damage, such as cardiac magnetic resonance imaging (MRI) for patients with cardiac disease, organ biopsy remains the gold standard to assess organ involvement.

CASE PRESENTATION

The cases of two patients, father and daughter with a W162C mutation, are described. The father presented with late-onset, cardiac Fabry disease, subsequently developing systolic dysfunction and heart failure. His daughter, while asymptomatic and with normal cardiac assessment (except for slightly reduced native T1 values by cardiac MRI), had already initial myocyte Gb3 deposits on the endomyocardial biopsy, allowing her to start therapy precociously and potentially modifying the course of her disease. A review of the literature concerning the W162C mutation is then provided, showing that it is usually associated to classic, multisystemic Fabry disease rather than the cardiac-restricted form as in these two cases.

CONCLUSIONS

Three main points can be concluded from this report. First, the W162C mutation can present with a more variegate phenotype than that predicted on a molecular basis. Second, endomyocardial biopsy was shown in this case to precede non-invasive investigation in determining organ involvement, justifying further studies on this potentially reliable technique, Third, difficulties can arise in the management of asymptomatic female carriers.

Clinical characteristics and outcome of end stage hypertrophic cardiomyopathy: Role of age and heart failure phenotypes

BACKGROUND

A minority of patients with hypertrophic cardiomyopathy (HCM) presents advanced heart failure (HF) during their clinical course, in the context of left ventricular (LV) remodeling with reduced LV ejection fraction (LVEF), or of severe diastolic dysfunction without impaired LVEF. Aim of this study was to describe a multicentric end stage (ES) HCM population and analyze clinical course and outcome among its different phenotypes.

METHODS

Data of all HCM patients from 7 Italian referral centres were retrospectively evaluated. ES was diagnosed in presence of: LVEF <50% (ES-rEF) or NYHA functional class ≥II with severe diastolic dysfunction (ES-pEF). Outcomes were: HCM-related and all-cause mortality; combined arrhythmic events; advanced HF treatments.

RESULTS

Study population included 331 ES patients; 87% presented ES-rEF and 13% ES-pEF. At ES recognition, patients with ES-pEF were more commonly females, had more frequently NYHA III/IV, atrial fibrillation and greater maximal LV wall thickness. Over a median follow-up of 5.6 years, 83 (25%) patients died, 46 (15%) experienced arrhythmic events and (26%) 85 received advanced HF treatments. Incidence of HCM-related and all-cause mortality, and of combined arrhythmic events did not differ in ES-pEF and ES-rEF patients, but ES-pEF patients were less likely to receive advanced HF treatments. Older age at ES recognition was an independent predictor of increased HCM-related mortality (p = 0.01) and reduced access to advanced HF treatments (p < 0.0001).

CONCLUSIONS

Two different HCM-ES phenotypes can be recognized, with ES-pEF showing distinctive features at ES recognition and receiving less frequently advanced HF treatments. Older age at ES recognition has a major impact on outcomes.

Real-world candidacy to mavacamten in a contemporary hypertrophic obstructive cardiomyopathy population

AIMS

In the EXPLORER-HCM trial, mavacamten reduced left ventricular outflow tract obstruction (LVOTO) and improved functional capacity of symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients. We sought to define the potential use of mavacamten by comparing real-world HOCM patients with those enrolled in EXPLORER-HCM and assessing their eligibility to treatment.

METHODS AND RESULTS

We collected information on HOCM patients followed up at 25 Italian HCM outpatient clinics and with significant LVOTO (i.e. gradient ≥30 mmHg at rest or ≥50 mmHg after Valsalva manoeuvre or exercise) despite pharmacological or non-pharmacological therapy. Pharmacological or non-pharmacological therapy resolved LVOTO in 1044 (61.2%) of the 1706 HOCM patients under active follow-up, whereas 662 patients (38.8%) had persistent LVOTO. Compared to the EXPLORER-HCM trial population, these real-world HOCM patients were older (62.1 ± 14.3 vs. 58.5 ± 12.2 years, p = 0.02), had a lower body mass index (26.8 ± 5.3 vs. 29.7 ± 4.9 kg/m2 , p < 0.0001) and a more frequent history of atrial fibrillation (21.5% vs. 9.8%, p = 0.027). At echocardiography, they had lower left ventricular ejection fraction (LVEF, 66 ± 7% vs. 74 ± 6%, p < 0.0001), higher left ventricular outflow tract gradients at rest (60 ± 27 vs. 52 ± 29 mmHg, p = 0.003), and larger left atrial volume index (49 ± 16 vs. 40 ± 12 ml/m2 , p < 0.0001). Overall, 324 (48.9%) would have been eligible for enrolment in the EXPLORER-HCM trial and 339 (51.2%) for treatment with mavacamten according to European guidelines.

CONCLUSIONS

Real-world HOCM patients differ from the EXPLORER-HCM population for their older age, lower LVEF and larger atrial volume, potentially reflecting a more advanced stage of the disease. About half of real-world HOCM patients were found eligible to mavacamten.

Emery-Dreifuss muscular dystrophy Type 1 is associated with a high risk of malignant ventricular arrhythmias and end-stage heart failure

BACKGROUND AND AIMS

Emery-Dreifuss muscular dystrophy (EDMD) is caused by variants in EMD (EDMD1) and LMNA (EDMD2). Cardiac conduction defects and atrial arrhythmia are common to both, but LMNA variants also cause end-stage heart failure (ESHF) and malignant ventricular arrhythmia (MVA). This study aimed to better characterize the cardiac complications of EMD variants.

METHODS

Consecutively referred EMD variant-carriers were retrospectively recruited from 12 international cardiomyopathy units. MVA and ESHF incidences in male and female variant-carriers were determined. Male EMD variant-carriers with a cardiac phenotype at baseline (EMDCARDIAC) were compared with consecutively recruited male LMNA variant-carriers with a cardiac phenotype at baseline (LMNACARDIAC).

RESULTS

Longitudinal follow-up data were available for 38 male and 21 female EMD variant-carriers [mean (SD) ages 33.4 (13.3) and 43.3 (16.8) years, respectively]. Nine (23.7%) males developed MVA and five (13.2%) developed ESHF during a median (inter-quartile range) follow-up of 65.0 (24.3-109.5) months. No female EMD variant-carrier had MVA or ESHF, but nine (42.8%) developed a cardiac phenotype at a median (inter-quartile range) age of 58.6 (53.2-60.4) years. Incidence rates for MVA were similar for EMDCARDIAC and LMNACARDIAC (4.8 and 6.6 per 100 person-years, respectively; log-rank P = .49). Incidence rates for ESHF were 2.4 and 5.9 per 100 person-years for EMDCARDIAC and LMNACARDIAC, respectively (log-rank P = .09).

CONCLUSIONS

Male EMD variant-carriers have a risk of progressive heart failure and ventricular arrhythmias similar to that of male LMNA variant-carriers. Early implantable cardioverter defibrillator implantation and heart failure drug therapy should be considered in male EMD variant-carriers with cardiac disease.

Diagnostic delay in arrhythmogenic cardiomyopathy

AIMS

Diagnosis of arrhythmogenic cardiomyopathy (ACM) may be challenging, as it comprises diverse phenotypes (right dominant, biventricular, and left dominant), and each may overlap with other clinical entities. The issue of differential diagnosis with conditions mimicking ACM has been previously highlighted; however, a systematic analysis of ACM diagnostic delay, and of its clinical implications, is lacking.

METHODS AND RESULTS

Data of all ACM patients from three Italian Cardiomyopathy Referral Centres were reviewed to assess the time from first medical contact to definitive ACM diagnosis; a significant diagnostic delay was defined as a time to ACM diagnosis ≥2 years. Baseline characteristics and clinical course of patients with and without diagnostic delay were compared. Of 174 ACM patients, 31% experienced diagnostic delay, with a median time to diagnosis of 8 years (20% in right-dominant ACM, 33% in left-dominant ACM, and 39% in biventricular). Patients with diagnostic delay, when compared with those without, more frequently exhibited an ACM phenotype with left ventricular (LV) involvement (74 vs. 57%, P = 0.04) and a specific genetic background (none had plakophilin-2 variants). The most common initial (mis)diagnoses were dilated cardiomyopathy (51%), myocarditis (21%), and idiopathic ventricular arrhythmia (9%). At follow-up, all-cause mortality was greater in those with diagnostic delay (P = 0.03).

CONCLUSION

Diagnostic delay is common in patients with ACM, particularly in the presence of LV involvement, and is associated with greater mortality at follow-up. Clinical suspicion and increasing use of tissue characterization by cardiac magnetic resonance in specific clinical settings are of key importance for the timely identification of ACM.

Electrocardiogram analysis in Anderson-Fabry disease: a valuable tool for progressive phenotypic expression tracking

Background

Electrocardiogram (ECG) has proven to be useful for early detection of cardiac involvement in Anderson-Fabry disease (AFD); however, little evidence is available on the association between ECG alterations and the progression of the disease.

Aim and Methods

To perform a cross sectional comparison of ECG abnormalities throughout different left ventricular hypertrophy (LVH) severity subgroups, providing ECG patterns specific of the progressive AFD stages. 189 AFD patients from a multicenter cohort underwent comprehensive ECG analysis, echocardiography, and clinical evaluation.

Results

The study cohort (39% males, median age 47 years, 68% classical AFD) was divided into 4 groups according to different degree of left ventricular (LV) thickness: group A ≤ 9 mm (n = 52, 28%); group B 10-14 mm (n = 76, 40%); group C 15-19 mm (n = 46, 24%); group D ≥ 20 mm (n = 15, 8%). The most frequent conduction delay was right bundle branch block (RBBB), incomplete in groups B and C (20%,22%) and complete RBBB in group D (54%, p < 0.001); none of the patients had left bundle branch block (LBBB). Left anterior fascicular block, LVH criteria, negative T waves, ST depression were more common in the advanced stages of the disease (p < 0.001). Summarizing our results, we suggested ECG patterns representative of the different AFD stages as assessed by the increases in LV thickness over time (Central Figure). Patients from group A showed mostly a normal ECG (77%) or minor anomalies like LVH criteria (8%) and delta wave/slurred QR onset + borderline PR (8%). Differently, patients from groups B and C exhibited more heterogeneous ECG patterns: LVH (17%; 7% respectively); LVH + LV strain (9%; 17%); incomplete RBBB + repolarization abnormalities (8%; 9%), more frequently associated with LVH criteria in group C than B (8%; 15%). Finally, patients from group D showed very peculiar ECG patterns, represented by complete RBBB + LVH and repolarization abnormalities (40%), sometimes associated with QRS fragmentation (13%).

Conclusions

ECG is a sensitive tool for early identification and long-term monitoring of cardiac involvement in patients with AFD, providing "instantaneous pictures" along the natural history of AFD. Whether ECG changes may be associated with clinical events remains to be determined.

Screening approaches to cardiac amyloidosis in different clinical settings: Current practice and future perspectives

Cardiac amyloidosis is a serious and progressive infiltrative disease caused by the deposition of amyloid fibrils in the heart. In the last years, a significant increase in the diagnosis rate has been observed owing to a greater awareness of its broad clinical presentation. Cardiac amyloidosis is frequently associated to specific clinical and instrumental features, so called "red flags", and it appears to occur more commonly in particular clinical settings such as multidistrict orthopedic conditions, aortic valve stenosis, heart failure with preserved or mildly reduced ejection fraction, arrhythmias, plasma cell disorders. Multimodality approach and new developed techniques such PET fluorine tracers or artificial intelligence may contribute to strike up extensive screening programs for an early recognition of the disease.

310 CLINICAL COURSE AND CHARACTERISTICS OF ADVANCED HEART FAILURE ASSOCIATED WITH ARRHYTHMOGENIC CARDIOMYOPATHY

Background

The prevalence and course of heart failure (HF) in arrhythmogenic cardiomyopathy (ACM) is unresolved, and previous studies have mostly focused on the right-dominant variant of the disease, less prone to HF. Conversely, ACM variants with left ventricular (LV) involvement are now increasingly recognized, often initially ‘mis-diagnosed’ as dilated cardiomyopathy. Aim of this study was therefore to describe the prevalence and clinical course of advance HF in the full clinical spectrum of ACM.

Methods

We retrospectively reviewed records of all ACM patients diagnosed before 2021 from 3 Italian Cardiomyopathy Referral Centres (Azienda Ospedaliero Universitaria Careggi; Policlinico Sant’Orsola; Azienda Ospedaliero Universitaria Sant’Andrea). LV involvement was diagnosed in the presence of subepicardial late gadolinium enhancement (LGE) in at least 3 contiguous segments in the same short-axis slice at cardiac magnetic resonance, independent of whether it fulfilled the 2010 Task Force criteria for right-dominant ACM (biventricular ACM) or not (left-dominant ACM); in this latter case, diagnosis was reached after careful exclusion of other differential diagnosis, and only when at least one of the following features was present: likely pathogenic/pathogenic genetic variant associated with ACM; familial history of ACM; electrocardiographic abnormalities suggestive of ACM with LV involvement. Advanced HF was defined as NYHA functional class III/IV and/or referral for heart transplantation. Median follow-up was 6 years.

Results

Forty-four out of 174 ACM patients (25%) developed advanced HF: 10 right-dominant ACM and 34 with LV involvement. Twenty ACM patients were initially diagnosed with dilated cardiomyopathy; as such, development of advanced HF in 17 cases preceded the diagnosis of ACM. Five patients were diagnosed with ACM after heart transplantation, by histological examination. In the other 22, median time from ACM diagnosis to advanced HF development was 4 years. As compared to those without, advanced HF patients were more likely to present LV involvement. During clinical course, 20 (46%) advanced HF patients received at least one appropriate ICD intervention, with 13 experiencing an electrical storm. Twenty-six (59%) patients required HF-related hospitalization, and 32 (72%) were referred for heart transplantation with 25 ultimately receiving it. ACM patients with advanced HF, compared to those without, experienced a higher rate of mortality (36% vs. 6%; OR 3.5 [95%CI: 1.4-8.7], p=0.01) and ventricular arrhythmic events (41% vs. 11%; OR 2.4 [95%CI: 1.1-5.0], p=0.02).

Conclusions

Advanced HF progression in ACM is not rare, and occurs more frequently in variants with LV involvement. Advanced HF is associated with increased mortality and arrhythmic risk.

486 ELECTROCARDIOGRAPHIC EVOLUTION IN ANDERSON-FABRY PATIENTS ON DISEASE SPECIFIC THERAPY

Background

Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder that have gained attention due to the availability of therapeutic options. Disease specific therapy (DST), either by enzyme replacement therapy or oral pharmacological chaperone, is the mainstay for AFD treatment. Although its widespread use, few data are available on the electrocardiographic variations associated with DST.

Purpose

To evaluate ECG findings and variations in AFD according to time duration of DST, comparing patients under long-term therapy with naïve patients starting therapy during follow-up.

Methods

One-hundred-seventy-nine AFD patients, ≥18 years old, with 2 readable ECGs, were recruited in the present multicentre study cohort. Two patients were excluded due to pacemaker (PM) implantation. Only patients on DST (n=107) were considered for final cohort and divided into 2 groups according to therapy duration: Group A (n=42) included patients treated for ≥12 months at the time of first evaluation, whereas Group B patients (n=65) started therapy during follow-up.

Results

Group A and Group B had not significant difference in terms of age at presentation (48[39-60] vs 48[36-56]years; p=0.856) and maximal wall thickness (13[11-15] vs 13[11-18]mm; p=0.090) whereas they differed for male prevalence (61% vs 38%; p=0.029) and classic phenotype (86% vs 29%; p&lt;0.0001). At baseline, more than half of both groups had ECG abnormalities (61% vs 61%; p=1.000). The prevalence among Group A and Group B of atrial fibrillation (AF 5% vs 6%; p=1.000), first degree atrioventricular block (AVB, 7% vs 5%; p=0.677), right bundle branch block (RBBB, complete 7% vs 8%; p=1.000; incomplete RBBB 14% vs 12%; p=0.776), left anterior fascicular block (LAFB, 10% vs 9%;p=1.000) and repolarization abnormalities (48% vs 38%; p=0.423) was not significantly different. Conversely, left ventricular hypertrophy (LVH) was more prevalent in Group A (64% vs 37%; p=0.010).

During the follow-up (57[60-28] months for Group A vs 70[37-85] months for Group B; p=0.152), both groups developed electrocardiographic alterations (38% vs 23%; p=0.127). Specifically, in GroupA, 4 (10%) patients presented AF, 1 (2%) AVB, 7 (17%) complete or incomplete RBBB, 4 (10%) LAFB, 1 (2%) LVH and 8 (19%) repolarization abnormalities. In Group B, 2 (3%) developed AF, 1 (2%) AVB, 7 (11%) complete or incomplete RBBB, 2(3%) LVH and 11(17%) repolarization abnormalities; none developed LAFB.

Conclusions

In this AFD cohort, both patients on chronic DST (Group A) and patients who started treatment during follow-up (Group B) developed ECG alterations. Treatment status didn't affect considerably the developing of ECG abnormalities and DST did not prevent ECG changes. ECG alterations during the follow-up were more frequent in Group A (38% vs 23%), mainly composed by classic phenotype and male patients, thus supporting a prompt start of therapy at an early stage.

Electrocardiographic findings in Anderson-Fabry patients on disease specific therapy: can treatment prevent ECG changes?

Background

Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder that have gained attention due to the availability of therapeutic options. Disease specific therapy (DST), either by enzyme replacement therapy or oral pharmacological chaperone, is the mainstay for AFD treatment. Although its widespread use, few data are available on the electrocardiographic variations associated with DST.

Purpose

To evaluate ECG findings and variations in AFD according to time duration of DST, comparing patients under long-term therapy with naïve patients starting therapy during follow-up.

Methods

One-hundred-seventy-nine AFD patients, ≥18 years old, with 2 readable ECGs, were recruited in the present multicentre study cohort. Two patients were excluded due to pacemaker (PM) implantation. Only patients on DST (n=107) were considered for final cohort and divided into 2 groups according to therapy duration: Group A (n=42) included patients treated for ≥12 months at the time of first evaluation, whereas Group B patients (n=65) started therapy during follow-up.

Results

Group A and Group B had no significant difference in terms of age at presentation (48 [39–60] vs 48 [36–56] years; p=0.856) and maximal wall thickness (13 [11–15] vs 13 [11–18] mm; p=0.090) whereas they differed for male prevalence (61% vs 38%; p=0.029) and classic phenotype (86% vs 29%; p&lt;0.0001). At baseline, more than half of both groups had ECG abnormalities (61% vs 61%; p=1.000). The prevalence among Group A and Group B of atrial fibrillation (AF, 5% vs 6%; p=1.000), first degree atrioventricular block (AVB, 7% vs 5%; p=0.677), right bundle branch block (RBBB, complete 7% vs 8%; p=1.000; incomplete RBBB 14% vs 12%; p=0.776), left anterior fascicular block (LAFB, 10% vs 9%; p=1.000) and repolarization abnormalities (48% vs 38%; p=0.423) was not significantly different. Conversely, left ventricular hypertrophy (LVH) was more prevalent in Group A (64% vs 37%; p=0.010).

During the follow-up period (57 [60–28] months for Group A vs 70 (37–85) months for Group B; p=0.152), both groups developed electrocardiographic alterations (38% vs 23%; p=0.127). In particular, in Group A, 4 (10%) patients presented AF, 1 (2%) AVB, 7 (17%) complete or incomplete RBBB, 4 (10%) LAFB, 1 (2%) LVH and 8 (19%) repolarization abnormalities. In Group B, 2 (3%) developed AF, 1 (2%) AVB, 7 (11%) complete or incomplete RBBB, 2 (3%) LVH and 11 (17%) repolarization abnormalities; none developed LAFB.

Conclusions

In this AFD cohort, both patients on chronic DST (Group A) and patients who started treatment during follow-up (Group B) developed ECG alterations. ECG changes during the follow-up were more frequent in Group A (38% vs 23%), mainly composed by classic phenotype and male patients, suggesting a prompt start of therapy at an early stage.

Funding Acknowledgement

Type of funding sources: None.

Diagnostic pathways leading to arrhythmogenic left ventricular cardiomyopathy in a single center cohort

Background

Despite major advances, the recognition of arrhythmogenic left ventricular cardiomyopathy (ALVC) remains challenging, since this clinical entity is often concealed in different clinical settings both in terms of clinical onset and imaging phenotype, resulting in significant delays in diagnosis with prognostic implications.

Purpose

To describe a single Center cohort of ALVC patients, focusing on the spectrum of clinical presentation and diagnostic pathways.

Methods

Patients were retrospectively evaluated between January 2012 and January 2022. Diagnosis was based on 1) ≥3 contiguous segments with subepicardial/midwall LGE in the LV at cardiac magnetic resonance (CMR) plus a likely pathogenic/pathogenic arrhythmogenic cardiomyopathy (ACM) associated genetic mutation and/or familial history of ACM and/or red flags for ALVC (i.e, negative T waves in V4–6/aVL, low voltages in limb leads) or 2) pathology examination of explanted hearts/autoptic cases suffering from sudden cardiac death (SCD). Patients with significant right ventricular involvement were excluded.

Results

Sixty-six patients were evaluated for suspected ALVC: 8 phenocopies were excluded (6 acute myocarditis and 2 sarcoidosis) after a comprehensive clinical and multi-modality instrumental evaluation. The final study cohort was composed by 56 patients (55% males, median age 45 years), from 36 families. Diagnostic pathways leading to diagnosis were: SCD in 4 (7%), ventricular arrhythmias in 11 (20%), chest pain in 9 (16%), heart failure in 7 (12%), and familial screening in 25 (45%) (Figure 1). An echocardiogram was available for all but 2 patients with SCD: 25 (46%) had normal phenotype, 17 (32%) had a hypokinetic non dilated cardiomyopathy, and 12 (22%) had a dilated cardiomyopathy (DCM). Of the 49 tested patients, 31 (63%) had a pathogenic/likely pathogenic DNA variant: desmoplakin (DSP, N=21), filamin C (FLNC, N=4), SCN5A (N=3) were the most frequently involved genes; 8 patients had a double gene mutation. Twenty-four patients (43%) had previously received a diagnosis other than ALVC: 10 idiopathic DCM, 9 acute myocarditis, 4 post-myocarditis DCM, 2 acute myocardial injury/non-ST elevated myocardial infarction. In 13 patients ALVC was diagnosed with the introduction of CMR in the diagnostic work-up of a DCM, in 2 cases the diagnosis was done with the pathology examination after heart transplantation. The median diagnostic delay was of 8 years, with a maximum of 20 years. It is worth nothing that patients from the same family might have different diagnostic pathways and phenotypes of ALVC (Figure 2).

Conclusions

ALVC is a challenging diagnosis, hidden in different clinical scenarios. Five main clinical pathways leading to ALVC diagnosis may be identified: ventricular arrhythmias, chest pain, heart failure, SCD at first presentation, and clinical/instrumental familial screening.

Funding Acknowledgement

Type of funding sources: None.

Electrocardiographic evolution in Anderson-Fabry disease patients on and off specific therapy: a potential marker to study the therapeutic cardiac goal

Background

Anderson Fabry disease (AFD) is an X-linked lysosomal storage disorder leading to a deficiency in α-galactosidase A and globotriasylceramide (Gb3) deposition in different organs, including the heart. In AFD patients electrocardiogram (ECG) represents an important tool to detect cardiac involvement. AFD specific therapy (enzyme replacement or chaperon therapy) has shown to modify the natural history of the disease and to decrease Gb3 levels, but so far there are no data on its influence on ECG evolution.

Purpose

To assess the progression of ECG features in AFD patients on and off specific disease therapy and to evaluate the potential role of ECG in studying the cardiac specific response to therapy.

Methods

We recruited 170 patients with an established AFD diagnosis, ≥18 years old (64 males 38%, median age 46±15 years) in a multicentre study cohort. We analysed their ECG evolution for a median follow-up of 64±48 months in patients off (group A, N=63) and on (group B, N=107) specific therapy.

Results

AFD patients off specific disease therapy (group A) had similar age at baseline compared to those on therapy (47±14 vs 44±12 years; p=0,171), however significantly differed for males prevalence [13 (21%) vs 51 (48%); p≤0,001], classic phenotype [36 (57%) vs 82 (77%); p&lt;0,001)] and maximal wall thickness [11±3 vs 13±4 mm; p≤0,0001]. As regards ECG features at baseline, group A showed a lower prevalence of repolarization anomalies [16 (25%) vs 51 (48%), p=0,005], left ventricular hypertrophy [14 (22%) vs 51 (48%), p=0,001], pseudo necrosis [4 (6%) vs 18 (17%) vs, p≤0,060] and short PR [2 (3%) vs 12 (11%), p=0.0845]. During the follow-up ECG progression was observed in 9 patients in group A (14%), characterized by the development of repolarization anomalies (N=5; 8%), incomplete right bundle block (N=4; 6%), shortening of PR interval (N=2; 3%), left ventricular hypertrophy (N=2; 3%), left atrial enlargement (N=2; 3%) and complete right bundle block (N=1; 2%). Differently, in group B an ECG evolution was observed in 31 patients (29%) characterized by the development of repolarization anomalies (N=19; 18%), left atrial enlargement (N=12; 12%), complete right bundle block (N=8; 8%), left anterior fascicular hemiblock (N=4; 4%), left bundle block (N=4, 4%) and left ventricular hypertrophy (N=3; 3%). Among patients off therapy we observed an improvement of ECG in 1 patient characterized by regression of repolarization anomalies, which could be explained with the presence of transient overload anomalies.

Conclusion

In AFD patients off and on specific disease therapy, ECG evolution was detected in 14% and 29% respectively, consistently with the more advanced cardiac involvement in patients on therapy (higher prevalence of male sex, classic phenotype and higher maximum wall thickness). The fact that one third of the patients showed ECG changes progression despite being on specific disease therapy could be relevant to better defined the therapeutic cardiac goal.

Funding Acknowledgement

Type of funding sources: None.

ECG as a storytelling of cardiac involvement evolution in Anderson Fabry disease

Background

Cardiac involvement in Anderson-Fabry disease (AFD) is related to a progressive glycosphingolipid storage over time and is characterized by left ventricular hypertrophy (LVH), conduction abnormalities and myocardial fibrosis. ECG is useful for early recognition of AFD, however evidence is limited on the association between ECG alterations and disease stage.

Purpose

To assess the relationship between ECG characteristics and progressive cardiac involvement, from the pre-hypertrophic phase to phenotypes with increasing degree of LVH.

Methods

In a multicenter cohort, 183 AFD patients (40% male, age 47±12 years, 60% affected by “classical AFD”) underwent ECG and transthoracic echocardiography. Patients were divided into 4 groups according to the different degree of LV thickness measured in parasternal short axis view: group A ≤9 mm (N=46, 25%), group B 10–14 mm (N=77, 42%), group C 15–19 mm (N=45, 25%) and group D ≥20 mm (N=15, 8%). Patients with pacemaker and under 18 years of age were excluded.

Results

A normal ECG was present in 89% in group A, 59% in group B, 11% in group C and it was absent in group D. Short PR (&lt;120 ms) was more frequent in group A, whereas with LVH increasing, median PR interval duration significantly prolonged among the 4 groups (136 [125–150]vs 141 [130–160] vs 160 [130–180] vs 170 [130–180] ms, p=0.002 respectively). Median P-wave duration was shorter in group A and B compared to group C and D (80 m vs 100 ms, p&lt;0.001), while both QRS and QTc gradually increased. Median Sokolow-Lyon voltage criteria statistically augmented among the groups (22 [18–26] vs 27 [20–33] vs 32 [25–45] vs 35 [18–40] mm, p&lt;0.001 respectively), along with right ventricular hypertrophy (0%, 1%, 11%, 8%, p=0.02). Right bundle branch block (RBBB) had a higher frequency in advanced stages (0%, 34%, 34%, 40%, p&lt;0.001), with a prevalence of complete RBBB of 46% in group D. Similarly, left anterior fascicular block (0%, 7%, 18%, 46%, p&lt;0.001) and QRS fragmentation (2%, 11%, 25%, 23%, p=0.009) were more common in advanced stages. No differences were found in left bundle branch block (LBBB), in low QRS voltages or in LV pre-excitation prevalence. According with the wall thickness increase, negative T waves were more frequent in lateral (4%, 21%, 70%, 77%, p&lt;0.001) and inferior leads (6%, 15%, 32%, 46%, p 0.001), as well as their association with ST-T depression (4%, 17%, 64%, 46%, p&lt;0.001). Giant negative T waves were present only in group C and D (16% and 31%) mainly representing a LVH distribution toward the apex.

Conclusions

ECG is a very useful tool to stage cardiac involvement evolution in AFD. Peculiar ECG characteristics evolve together with LV wall thickness: incomplete and progressively complete RBBB usually associated (preceding or following) LVH and/or typical repolarization abnormalities in inferior or lateral leads and giant negative T waves in the more advanced stages are the most frequent and typical ECG patterns.

Funding Acknowledgement

Type of funding sources: None.

Clinical presentations leading to arrhythmogenic left ventricular cardiomyopathy

OBJECTIVES

To describe a cohort of patients with arrhythmogenic left ventricular cardiomyopathy (ALVC), focusing on the spectrum of the clinical presentations.

METHODS

Patients were retrospectively evaluated between January 2012 and June 2020. Diagnosis was based on (1) ≥3 contiguous segments with subepicardial/midwall late gadolinium enhancement in the left ventricle (LV) at cardiac magnetic resonance plus a likely pathogenic/pathogenic arrhythmogenic cardiomyopathy (AC) associated genetic mutation and/or familial history of AC and/or red flags for ALVC (ie, negative T waves in V4-6/aVL, low voltages in limb leads, right bundle branch block like ventricular tachycardia) or (2) pathology examination of explanted hearts or autoptic cases suffering sudden cardiac death (SCD). Significant right ventricular involvement was an exclusion criterion.

RESULTS

Fifty-two patients (63% males, age 45 years (31-53)) composed the study cohort. Twenty-one (41%) had normal echocardiogram, 13 (25%) a hypokinetic non-dilated cardiomyopathy (HNDC) and 17 (33%) a dilated cardiomyopathy (DCM). Of 47 tested patients, 29 (62%) were carriers of a pathogenic/likely pathogenic DNA variant. Clinical contexts leading to diagnosis were SCD in 3 (6%), ventricular arrhythmias in 15 (29%), chest pain in 8 (15%), heart failure in 6 (12%) and familial screening in 20 (38%). Thirty patients (57%) had previously received a diagnosis other than ALVC with a diagnostic delay of 6 years (IQR 1-7).

CONCLUSIONS

ALVC is hidden in different clinical scenarios with a phenotypic spectrum ranging from normal LV to HNDC and DCM. Ventricular arrhythmias, chest pain, heart failure and SCD are the main clinical presentations, being familial screening essential for the affected relatives' identification.

[Mitral valve prolapse and mitral annulus disjunction: be aware of a potential arrhythmogenic substrate]

Mitral valve prolapse is a relatively common disease with a good overall prognosis. However, in specific clinical and instrumental contexts, patients at high risk of ventricular arrhythmias and sudden cardiac death can be identified. Female sex, history of palpitations or syncope, bi-leaflet myxomatous valve, ECG repolarization abnormalities in the inferior leads, complex ventricular arrhythmias, left ventricular fibrosis detected by cardiac magnetic resonance correlate with a higher risk clinical profile. Additionally, morpho-functional abnormalities of the mitral valve annulus, particularly mitral annulus disjunction, may cause a mechanical stretch at the inferior basal ventricular wall and posterior papillary muscles, predisposing to myocardial fibrosis and arrhythmias. A risk stratification strategy is needed to identify patients with mitral valve prolapse and/or mitral annulus disjunction at high risk of arrhythmias; however, few data are available. Further prospective multicenter studies are warranted, focusing on medical therapy, the role of implantable cardioverter-defibrillators for primary prevention, efficacy of targeted catheter ablation or mitral valve surgery.

Standard ECG for differential diagnosis between Anderson-Fabry disease and hypertrophic cardiomyopathy

OBJECTIVES

To evaluate the role of the ECG in the differential diagnosis between Anderson-Fabry disease (AFD) and hypertrophic cardiomyopathy (HCM).

METHODS

In this multicentre retrospective study, 111 AFD patients with left ventricular hypertrophy were compared with 111 patients with HCM, matched for sex, age and maximal wall thickness by propensity score. Independent ECG predictors of AFD were identified by multivariate analysis, and a multiparametric ECG score-based algorithm for differential diagnosis was developed.

RESULTS

Short PR interval, prolonged QRS duration, right bundle branch block (RBBB), R in augmented vector left (aVL) ≥1.1 mV and inferior ST depression independently predicted AFD diagnosis. A point-by-point ECG score was then derived with the following diagnostic performances: c-statistic 0.80 (95% CI 0.74 to 0.86) for discrimination, the Hosmel-Lemeshow χ² 6.14 (p=0.189) for calibration, sensitivity 69%, specificity 84%, positive predictive value 82% and negative predictive value 72%. After bootstrap resampling, the mean optimism was 0.025, and the internal validated c-statistic for the score was 0.78.

CONCLUSIONS

Standard ECG can help to differentiate AFD from HCM while investigating unexplained left ventricular hypertrophy. Short PR interval, prolonged QRS duration, RBBB, R in aVL ≥1.1 mV and inferior ST depression independently predicted AFD. Their systematic evaluation and the integration in a multiparametric ECG score can support AFD diagnosis.

Pediatric Restrictive Cardiomyopathies

Restrictive cardiomyopathy (RCM) is the least frequent phenotype among pediatric heart muscle diseases, representing only 2.5-3% of all cardiomyopathies diagnosed during childhood. Pediatric RCM has a poor prognosis, high incidence of pulmonary hypertension (PH), thromboembolic events, and sudden death, is less amenable to medical or surgical treatment with high mortality rates. In this scenario, heart transplantation remains the only successful therapeutic option. Despite a shared hemodynamic profile, characterized by severe diastolic dysfunction and restrictive ventricular filling, with normal ventricle ejection fraction and wall thickness, RCM recognizes a broad etiological spectrum, consisting of genetic/familial and acquired causes, each of which has a distinct pathophysiology and natural course. Hence, the aim of this review is to cover the causes, clinical presentation, diagnostic evaluation, treatment, and prognosis of pediatric RCM.

Electrocardiographic differences between Anderson-Fabry and sarcomeric hypertrophic cardiomyopathy and correlation with cardiac magnetic resonance

Background

Differential diagnosis between Anderson-Fabry (AF) and sarcomeric hypertrophic cardiomyopathy (HCM) is often very challenging particularly in AF patients with late onset cardiac involvement.

Purpose

To gain new insights from standard electrocardiogram (ECG) in AF disease for differential diagnosis from sarcomeric HCM. Additionally, to better understand ECG features in AF patients, a correlation substudy ECG-cardiac magnetic resonance (CMR) has been performed.

Methods

From 162 patients with definite diagnosis of AF disease, 111 [65 males, median age 57 (51–67) years] with pathologic left ventricular hypertrophy (LVH) (Group A) were compared with 111 sarcomeric HCM patients (Group B) sex, age and maximal wall thickness matched by 1:1 propensity score.

Results

AF patients showed shorter PR interval [155 (140–180) vs 163 (149–184) msec; p=0.005) and wider QRS interval [110 (100–134) vs 100 (90–106) msec; p&lt;0.0001). Additionally AF patients had a higher prevalence of complete (22% vs 3%; p&lt;0.0001) and incomplete (13% vs 1%; p&lt;0.0001) right bundle branch block (RBBB) and a higher percentage of ST segment depression (12% vs 1%; p=0.001) and inferior negative T waves (34% vs 19%; p=0.01). No differences in terms of Sokolow-Lyon and Cornell scores were found whereas total QRS score was higher in Group A [20 (16–27) vs 18 [14–22] mV; p=0.0004). Low QRS voltages and inferior Q waves were not present in AF patients. Among the 69 AF patients who underwent MRI, the 44 with late gadolinium enhancement (LGE) were older [59 (52–66) vs 53 (40–59) years; p=0.017] and had more frequently negative T waves on ECG, particularly in the inferior leads (64% vs 8%; p&lt;0.0001), compared to the 25 without LGE. At multivariate analysis, age and negative T waves were independently associated to the presence of LGE on CMR.

Conclusions

Compared to matched sarcomeric HCM, AF patients had a shorter PR, wider QRS and a higher percentage of RBBB in relation to to the different aetiology (storage vs “pure” hypertrophy). The higher total QRS score and the absence of inferior Q waves could reflect the more frequent concentric distribution of LVH. Additionally negative T waves, especially in inferior leads, are related to the presence of LGE on CMR (often in the postero-lateral wall).

Funding Acknowledgement

Type of funding source: None

A Pathogenic Galactosidase A Mutation Coexisting With an MYBPC3 Mutation in a Female Patient With Hypertrophic Cardiomyopathy

The coexistence of GLA (Pro259Ser, c.775C>T) and MYBPC3 (c.1351+2T>C) mutations was found in a female patient with hypertrophic cardiomyopathy. Histology documented abundant vacuolisation with osmiophilic lamellar bodies and positive Gb3 immunohistochemistry. In the presence of a hypertrophic cardiomyopathy phenotype, the systematic search for unusual findings is mandatory to rule out a phenocopy.

Differences in cardiac phenotype and natural history of laminopathies with and without neuromuscular onset

Objective

To investigate differences in cardiac manifestations of patients affected by laminopathy, according to the presence or absence of neuromuscular involvement at presentation.

Methods

We prospectively analyzed 40 consecutive patients with a diagnosis of laminopathy followed at a single centre between 1998 and 2017. Additionally, reports of clinical evaluations and tests prior to referral at our centre were retrospectively evaluated.

Results

Clinical onset was cardiac in 26 cases and neuromuscular in 14. Patients with neuromuscular presentation experienced first symptoms earlier in life (11 vs 39 years; p <  0.0001) and developed atrial fibrillation/flutter (AF) and required pacemaker implantation at a younger age (28 vs 41 years [p = 0.013] and 30 vs 44 years [p = 0.086] respectively), despite a similar overall prevalence of AF (57% vs 65%; p = 0.735) and atrio-ventricular (A-V) block (50% vs 65%; p = 0.500). Those with a neuromuscular presentation developed a cardiomyopathy less frequently (43% vs 73%; p = 0.089) and had a lower rate of sustained ventricular tachyarrhythmias (7% vs 23%; p = 0.387). In patients with neuromuscular onset rhythm disturbances occurred usually before evidence of cardiomyopathy. Despite these differences, the need for heart transplantation and median age at intervention were similar in the two groups (29% vs 23% [p = 0.717] and 43 vs 46 years [p = 0.593] respectively).

Conclusions

In patients with laminopathy, the type of disease onset was a marker for a different natural history. Specifically, patients with neuromuscular presentation had an earlier cardiac involvement, characterized by a linear and progressive evolution from rhythm disorders (AF and/or A-V block) to cardiomyopathy.

P6455Differences in cardiac phenotype and natural history of laminopathies with and without neuromuscular presentation

Aim

To look for differences in cardiac phenotype and natural history of patients affected by laminopathy, according to the presence or less of neuromuscular involvement at clinical presentation.

Methods

We prospectively analyzed 47 consecutive pts with a genetic diagnosis of laminopathy followed at a single centre between 1994 and 2017. Additionally, reports of clinical and instrumental evaluations before referral at our centre were retrospectively evaluated.

Results

Neuromuscular presentation, mainly as Emery-Dreifuss muscular dystrophy (EDMD), was present in 21 (46%) cases (14 LMNA and 7 EMD gene mutations). These pts had symptoms earlier (9 vs 39 years, p<0.001) in life compared to pts without neuromuscular onset (26 LMNA gene mutations), and clinical manifestations anticipated the first evidence of cardiac disease by a mean time of 15±8 years (maximum time gap of 38 years). Despite a similar prevalence of atrial fibrillation/flutter (AF) (71% vs 65%, p=0.758) and atrio-ventricular blocks (48% vs 65%, p=0.250), pts with neuromuscular onset experienced AF and pace-maker implantation at a significantly younger age (27 vs 41 yrs, p=0.015 and 23 vs 44 yrs, p=0.027 respectively). Differently a higher prevalence of sinus node dysfunction (33% vs 4%; p=0.015) and atrial paralysis (14% vs 4%; p=0.311) was reported in pts with neuromuscular onset. Prevalence of cardiomyopathy (CMP) (73% vs 33%, p=0.008) and sustained ventricular tachyarrhythmias were higher among pts with cardiac onset (23% vs 4%, p=0.111) whereas the prevalence of heart transplantations and median age of recipients were similar in the two groups (24% vs 20%, p=1.000 and 46 vs 43, p=0.592 years respectively). All pts with neuromuscular onset who received a diagnosis of CMP had a previous history of rhythm disturbance except 2 cases, where a concomitant diagnosis of the 2 disorders was formulated. On the contrary a strict temporal progression from rhythm disturbances to CMP (or viceversa) was not appreciable in the other group: AF and AVBs could precede the diagnosis of CMP be diagnosed at the same time or later.

Conclusions

In pts affected by laminopathy neuromuscular involvement, when present, was most often the first clinical manifestation and preceded cardiological involvement, with a long time frame in some cases. Except for sinus node dysfunction, much more frequent in patients with EDMD, a similar prevalence of rhythm disturbances was reported, although pts with neuromuscular clinical onset were younger at diagnosis of AF and at PM implantation. Pts without neuromuscular presentation had a higher prevalence of CMP and ventricular arrhythmias, albeit a similar rate of heart transplantation. In pts with neuromuscular onset, cardiac involvement was characterized by a stepwise progression from rhythm disturbances to CMP, where a strict temporal progression from rhythm disturbances to CMP was not observed in the group of pts without neuromuscular clinical onset.

P900Electrocardiographic findings in Anderson-Fabry disease versus sarcomeric hypertrophic cardiomyopathy

Background

Cardiac involvement is one of the most frequent and disabling organ damage in Anderson-Fabry (AF) disease, causing hypertrophic cardiomyopathy (HCM), conduction disturbances, arrhythmias and coronary disease. Differential diagnosis from sarcomeric HCM is often very challenging, especially for patients with exclusive cardiac involvement.

Purpose

To gain new insights from standard electrocardiogram (ECG) in AF disease, and identify ECG differences from sarcomeric HCM.

Methods

Sixty-two consecutive patients (27 males, mean age: 62±16 years) with definite diagnosis of AF disease from 2 Italian centres were evaluated for ECG analysis and divided in 2 groups, according to the presence (Group A, N=39) or the absence (Group B, N=26) of cardiac involvement [hypertrophy detected at echocardiogram or cardiac magnetic resonance (CMR)]. All ECGs were analysed by 2 independent investigators. For Group A, when CMR was performed, a correlation between CMR and ECG was assessed. Patients with cardiac involvement were matched with 78 sarcomeric HCM patients according to sex, age and septal wall thickness on echocardiogram.

Results

Two AF patients out 39 with cardiac involvement (5%) had normal ECG. Short PR and I degree atrio-ventricular (AV) block were both reported in 6 (15%) cases. Twenty-six (67%) patients showed left ventricular hypertrophy and the majority (85%) had abnormal repolarization. CMR was performed in 22 patients (56%); the 11 (50%) patients with replacement fibrosis had a higher mean Sokolow-Lyon score (4.1±1.8 vs 2.9±1.0 mV; p=0.05), more frequent ST segment depression (82 vs 27%; p=0.03) and negative T waves (91 vs 36%; p=0.027; sensitivity: 90%; specificity: 63%), compared with the 11 without replacement fibrosis.

When compared with sarcomeric HCM, AF patients with cardiac involvement had a significantly wider QRS (120±30 vs 100±16 msec; p<0.0001), a higher frequency of right bundle branch block (RBBB) (18 vs 3%; p=0.01), ST segment depression (54 vs 20%; p<0.0001) and negative T waves (72 vs 46%; p=0.01), typically in the inferior leads (44 vs 14%; p<0.0001). No significant differences in terms of pseudo-necrosis and QRS voltages were found.

Among Group B AF patients (26, mean age: 36±12 years), 4 had short PR and 5 incomplete RBBB. Four had an abnormal ECG (1 left atrial enlargement, 2 unspecific repolarization abnormalities, 1 Sokolow score of 3.5 mV).

Conclusions

Standard ECG can detect cardiac involvement in AF disease. A good correlation was reported between repolarization abnormalities and replacement fibrosis on CMR. Wide QRS and RBBB were more frequent among AF patients compared to age-sex-matched sarcomeric HCM ones, probably due to the different aetiology of the diseases (infiltrative disease vs pure hypertrophy).

The complex interplay between fitness, genetics, lifestyle, and inflammation in the pathogenesis of coronary atherosclerosis: lessons from the Amazon rainforest

Far from only being a modern disease, atherosclerosis has also been reported also in ancient civilizations, as shown in some studies conducted on Mummies from different latitudes. Conventional cardiovascular (CV) risk factors can explain more than 90% of the attributable risk of coronary artery disease (CAD). In this regard, Tsimane Aborigenous of Amazon rainforest, conducting a subsistence lifestyle with low prevalence of CV risk factors, present the lowest reported prevalence of CAD in the world, despite an elevated inflammatory burden. Experimental and clinical studies have supported the theory that other factors, like genetics and inflammation, are involved in atherosclerosis. Indeed, a large clinical randomized study (CANTOS trial) tested the anti-inflammatory properties of canakinumab, and provided the first evidence to support the ‘inflammation hypothesis’. Another field of research, based on Mendelian randomization studies, supports the appealing hypothesis that correcting CV risk factors earlier in life, may prevent or delay the progression of CAD. All these data prove that atherosclerosis is the expression of a complex, dynamic, and continuous interaction between environment and genetics that begins at conception and continues through adulthood.