Cardiac Involvement In Fabry Disease Research Articles

Progress in diagnosis and treatment of the cardiac involvement of Fabry disease

Progress in diagnosis and treatment of the cardiac involvement of Fabry disease

Increased cardiac involvement in Fabry disease using blood-corrected native T1 mapping

Fabry disease (FD) is a rare lysosomal storage disorder resulting in myocardial sphingolipid accumulation which is detectable by cardiovascular magnetic resonance as low native T1. However, myocardial T1 contains signal from intramyocardial blood which affects variability and consequently measurement precision and accuracy. Correction of myocardial T1 by blood T1 increases precision. We therefore deployed a multicenter study of FD patients (n = 218) and healthy controls (n = 117) to investigate if blood-correction of myocardial native T1 increases the number of FD patients with low T1, and thus reclassifies FD patients as having cardiac involvement. Cardiac involvement was defined as a native T1 value 2 standard deviations below site-specific means in healthy controls for both corrected and uncorrected measures. Overall low T1 was 135/218 (62%) uncorrected vs. 145/218 (67%) corrected (p = 0.02). With blood-correction, 13/83 previously normal patients were reclassified to low T1. This reclassification appears clinically relevant as 6/13 (46%) of reclassified had focal late gadolinium enhancement or left ventricular hypertrophy as signs of cardiac involvement. Blood-correction of myocardial native T1 increases the proportion of FD subjects with low myocardial T1, with blood-corrected results tracking other markers of cardiac involvement. Blood-correction may potentially offer earlier detection and therapy initiation, but merits further prospective studies.

Assessing small fiber neuropathy and subtle cardiac involvement in Fabry disease

Assessing small fiber neuropathy and subtle cardiac involvement in Fabry disease

Cardiac involvement in Fabry disease - A non-invasive assessment and the role of specific therapies.

Fabry disease is an X-linked inherited metabolic disorder due to the pathogenic mutation of the GLA gene, which codes lysosomal enzyme alpha-galactosidase A. The resultant accumulation of glycosphingolipids causes various systemic symptoms in childhood and adolescence, and major organ damage in adulthood. Cardiac involvement is important as the most frequent cause of death in Fabry disease patients. Progressive left ventricular hypertrophy with varying degrees of contractile dysfunction as well as conduction abnormalities and arrhythmias are typical cardiac features, and these findings can be evaluated in detail via non-invasive modalities, such as an electrocardiogram, echocardiography and cardiac magnetic resonance. In addition, specific therapies of enzyme replacement therapy and pharmacological chaperone therapy are available, and their beneficial effects on cardiac involvement have been reported. This minireview highlights recent evidence concerning non-invasive modalities for assessing cardiac involvement in Fabry disease and the effects of enzyme replacement therapy and pharmacological chaperone therapy on the findings of those modalities.

Cardiac Magnetic Resonance Features of Fabry Disease: From Early Diagnosis to Prognostic Stratification

In the past few years, the wide application of cardiac magnetic resonance (CMR) significantly changed the approach to the study of cardiac involvement in Fabry Disease (FD). The possibility to perform non-invasive tissue characterization, including new sequences such as T1/T2 mapping, offered a powerful tool for differential diagnosis with other forms of left ventricular hypertrophy. In patients with confirmed diagnosis of FD, CMR is the most sensitive non-invasive technique for early detection of cardiac involvement and it provides new insight into the evolution of cardiac damage, including gender-specific features. Finally, CMR multiparametric detection of subtle changes in cardiac morphology, function and tissue composition is potentially useful for monitoring the efficacy of specific treatment over time. This paper aims to provide a comprehensive review of current knowledge regarding the application of CMR in FD cardiac involvement and its clinical implication.

Multi-Modality Cardiovascular Imaging Assessment in Fabry Disease

Fabry disease (FD) is a rare X-linked lysosomal storage disorder manifesting as progressive multi-organ accumulation of sphingolipids due to deficiency in the enzyme α-Galactosidase A. Sphingolipid accumulation can take place in all cardiac cell types which manifests as left ventricular hypertrophy, microvascular ischaemia, conduction abnormalities, arrhythmia, heart failure, and valvular disease. The use of advanced cardiovascular imaging techniques have enabled clinicians to stage and prognosticate the disease and guide therapy. Transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) in conjunction are the hallmark imaging modalities to allow for this assessment. Traditionally, the assessment of cardiac involvement in FD was based on the assessment of maximal wall thickness (MWT) and the development of left ventricular hypertrophy (LVH). It is now understood that sphingolipid accumulation takes place before the development of LVH. Advances in techniques within TTE and CMR, particularly that of strain assessment and T1/T2 mapping, have meant that Fabry cardiomyopathy (FCM) can be diagnosed earlier in the disease process. This potentially provides a window for initiation of enzyme replacement therapy (ERT) at a stage where it is likely to have the most beneficial effect in reducing the high mortality associated with FCM. This review outlines the advances in multimodality imaging in staging and prognosticating FCM, as well as the applications of cardiac imaging in assessing symptoms and complications of FCM.

Lyso-Gb3 as a biomarker for renal and cardiac involvement in Fabry disease: An analysis from the Fabry Outcome Survey (FOS)

Lyso-Gb3 as a biomarker for renal and cardiac involvement in Fabry disease: An analysis from the Fabry Outcome Survey (FOS)

Effect of migalastat on cardiac involvement in Fabry disease: preliminary results from MAIORA study

Abstract Background Fabry Disease (FD) is a rare X-linked lysosomal storage disorder. Since 2016, pharmacological chaperone Migalastat has been approved for treatment of FD patients with amenable mutations to stabilize defective forms of the enzyme α-galactosidase A. A small but significant reduction in left ventricular (LV) mass after 18 months of Migalastat treatment has been previously reported by echocardiography. However, an integrated assessment of the effect of Migalastat on cardiac involvement, combining LV morphology and tissue composition by CMR with exercise capacity by cardiopulmonary test, is lacking. Purpose To determine the effects of 18 month treatment with Migalastat on LV mass, native T1 value and functional capacity in naïve patients with genetically confirmed FD cardiomyopathy. Methods Sixteen treatment naïve FD patients (4 females, mean age 46.4±16.2) with amenable mutations and signs of cardiac involvement underwent CMR with T1 mapping and cardio-pulmonary testing before and after 18 months of migalastat therapy as a part of MAIORA Study. Cardiac involvement was defined as presence of reduced native T1 values at CMR (a surrogate of myocardial glycosphingolipid storage) and/or LV hypertrophy (LVH). Nine patients (56%, 2 females, mean age 56.4±12.7 years) had LVH at baseline. Results Migalastat treatment was well tolerated in all patients, with no serious adverse event. No change in LV mass was detected at 18 months compared to baseline (95.2 (66.0–184.0) vs 103.0 (71.0–182.0) g/m2; p=0.5516). The same result was found after stratifying patients according to presence/absence of Late Gadolinium Enhancement (LGE) (LGE+ n=8, 2 females, mean age 56.2±13.1 years). There was a trend towards an increased native septal T1 value (870.0 (848–882) vs 860.0 (833.0–875.0) ms at baseline; p 0.056) with unchanged extracellular volume (ECV) (0.26 (0.23–0.028) vs 0.26 (0.22–0.29) at baseline; p 0.276) in the overall cohort. An improvement in functional capacity with a trend towards an increase in percent-predicted peak VO2 (72.0 (61.25–80.75) vs 67.0 (45.2–79.2) at baseline; p 0.056) and a significant increase in VO2 at anaerobic threshold (14.8 (12.6–20.0) vs 13.10 (6.8–18.6) ml/kg/min at baseline; p 0.004) was reported in the total population. Conclusion In treatment naïve FD patients with amenable mutations and signs of early or overt cardiac involvement, 18-month treatment with Migalastat stabilized LV mass both in patients with and without LGE and was associated with an improvement in exercise tolerance. The trend towards an increase in T1 value associated with unchanged ECV suggests partial clearance of cardiomyocyte glycoshingolipid storage. These real-world data are consistent with a beneficial impact of migalastat on the progression of cardiac involvement in FD. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Amicus Therapeutics

Twist, left ventricular longitudinal and circumferential strain are early markers of cardiac involvement in Fabry disease

Abstract Introduction Fabry disease (FD) is an X-linked progressive and multisystemic disease. Cardiac involvement is common and left ventricular hypertrophy (LVH) is the main cardiac manifestation. Purpose To determine the differences in echocardiographic parameters between FD patients without LVH and healthy controls. Methods We conducted a prospective study encompassing FD patients followed in a Reference Center of Lysosomal Storage Disorders. All patients performed a complete echocardiographic evaluation, including left ventricular strain analysis by two-dimensional speckle tracking imaging. Demographic, clinical characteristics and echocardiographic parameters were analysed. FD patients without LVH were compared with healthy controls, using Chi-square test for categorical variables and Student's T-test for continuous variables. The significance level was 0,05. Results A total of 91 FD patients were included, with a median age of 51 years-old and 62,6% of female predominance. 16,5% of patients were under enzymatic replacement therapy with agalsidase alpha and 7,7% were treated with chaperone therapy (migalastat). 58 patients (64%) did not present LVH. FD patients without LVH were younger (44,2 vs 52,9 years-old, p<0,001), had higher interventricular septum thickness (9,3 vs 8,4 mm, p=0,006) and left ventricular mass index (77,2 vs 68,4 g/m2, p=0,003) than healthy controls. Left ventricular ejection fraction was preserved in both groups (63,3% vs 65,4%; p=0,067). Global longitudinal strain (−19,6% vs −20,9%; p=0,003) and global circumferential strain (−17,9% vs −20,9%; p<0,001) were significantly lower in FD patients without LVH compared to healthy controls. Global radial strain was also lower, although without statistical significance (36,4% vs 41,4%, p=0,058). FD patients without LVH presented a lower base-to-apex circumferential strain gradient (5,7% vs 7,7%; p=0,035), but a higher base-to-apex longitudinal strain gradient (7,5% vs 4,3%; p<0,001), compared to controls. Left ventricular twist was also significantly lower in FD patients without LVH (13,8° vs 21,7°, p<0,001). Conclusion Left ventricular strain and twist analysis are useful to identify subclinical myocardial impairment in FD patients without LVH. Funding Acknowledgement Type of funding sources: None.

Value of Left Ventricular Feature Tracking Strain Analysis for Detection of Early Cardiac Involvement in Fabry Disease (FD).

Purpose: Detection of cardiac involvement in Fabry disease (FD) is of high importance for treatment management. Native T1 mapping especially showed great potential for detection of early cardiac manifestations. Echocardiographic studies showed strain abnormalities in FD patients, but data on MRI feature tracking strain analysis (FT-SA) is limited. Therefore, the aim of our study was to evaluate the potential of FT-SA compared to native T1 and the FD specific biomarker Globotriaosylsphingosine (LysoGb3). Methods: 28 consecutive FD patients (18 female; 47.8 years ± 17.4 standard deviation (SD)) and 28 control subjects (18 female; 46.6 years ± 18.2 SD) underwent cardiac MRI at 1.5 Tesla. Global native T1 times and left ventricular FT-SA were evaluated. Results were correlated to serum Lyso-Gb3-levels. Results: Native T1 times, global longitudinal (GLS) and global radial strain (GRS) were significantly reduced in FD patients (p < 0.0064, p = 0.0009 and p = 0.0184, respectively). Moreover, native T1 times and GLS were significantly lower in Lyso-Gb3 positive FD patients (p < 0.005 and p = 0.03). GLS, native T1 times showed significant moderate correlations to LysoGb3 (p = 0.002 and p < 0.001). Furthermore, GLS and native T1 times reduce when LysoGb3 was elevated and increasingly with presence of left ventricular hypertrophy (LVH) or late gadolinium enhancement (LGE). Conclusions: Native T1 times and strain values differ significantly between FD patients and control subjects and showed promising correlations to the FD specific biomarker LysoGb3. We therefore conclude that strain abnormalities occur early beside native T1 reductions in cardiac FD involvement. Large scale trials are needed to verify our findings.

2021 TSOC Expert Consensus on the Clinical Features, Diagnosis, and Clinical Management of Cardiac Manifestations of Fabry Disease.

Fabry disease (FD) is an X-linked, rare inherited lysosomal storage disease caused by α-galactosidase A gene variants resulting in deficient or undetectable α-galactosidase A enzyme activity. Progressive accumulation of pathogenic globotriaosylceramide and its deacylated form globotriaosylsphingosine in multiple cell types and organs is proposed as main pathophysiology of FD, with elicited pro-inflammatory cascade as alternative key pathological process. The clinical manifestations may present with either early onset and multisystemic involvement (cutaneous, neurological, nephrological and the cardiovascular system) with a progressive disease nature in classic phenotype, or present with a later-onset course with predominant cardiac involvement (non-classical or cardiac variant; e.g. IVS4+919G>A in Taiwan) from missense variants. In either form, cardiac involvement is featured by progressive cardiac hypertrophy, myocardial fibrosis, various arrhythmias, and heart failure known as Fabry cardiomyopathy with potential risk of sudden cardiac death. Several plasma biomarkers and advances in imaging modalities along with novel parameters, cardiac magnetic resonance (CMR: native T1/T2 mapping) for myocardial tissue characterization or echocardiographic deformations, have shown promising performance in differentiating from other etiologies of cardiomyopathy and are presumed to be helpful in assessing the extent of cardiac involvement of FD and in guiding or monitoring subsequent treatment. Early recognition from extra-cardiac red flag signs either in classic form or red flags from cardiac manifestations in cardiac variants, and awareness from multispecialty team work remains the cornerstone for timely managements and beneficial responses from therapeutic interventions (e.g. oral chaperone therapy or enzyme replacement therapy) prior to irreversible organ damage. We aim to summarize contemporary knowledge based on literature review and the gap or future perspectives in clinical practice of FD-related cardiomyopathy in an attempt to form a current expert consensus in Taiwan.

Recognition of pre-hypertrophic cardiac involvement in Fabry Disease based on automated electrocardiographic measures

BackgroundVarious electrocardiographic (ECG) indices have been shown to be useful for early recognition and staging of cardiac involvement in Fabry Disease (FD). However, many of them lack acceptable sensitivity and specificity. We assessed the value of automated ECG measures to discriminate between pre-hypertrophic FD and healthy individuals. Methods and resultsNormal ECGs from 1496 healthy individuals (57.4% male, age 37.4 ± 13 years) were compared to those of 142 FD patients without LVH (37.3% male, age 41.5 ± 18 years). All ECGs were analyzed centrally and a total of 429 automated ECG measures per individual were included for step-wise analysis. The Cramer V statistic was first used to pick out those parameters which were helpful in discriminating between the two groups and a final selection was made by using two models, namely the FLD (Fisher Linear Discrimination) and the Logistic model, to optimise diagnostic performance for the detection of cardiac involvement in FD patients vs. specificity in healthy individuals.The three-step statistical analysis identified 9 ECG parameters as most significant for the discrimination between the groups. The combined discriminant score yielded 64% sensitivity and 97% specificity for correct classification of FD patients in the test sample with a logistic area under curve of the ROC analysis of 0.97. ConclusionThe combination of automated ECG measures identified via a stepwise statistical approach may be useful for detection of FD patients in the pre-hypertrophic stage. These data are promising for screening purposes in the very early stages of FD cardiomyopathy and warrant prospective confirmation.

Fabry Disease and the Heart: A Comprehensive Review

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations of the GLA gene that result in a deficiency of the enzymatic activity of α-galactosidase A and consequent accumulation of glycosphingolipids in body fluids and lysosomes of the cells throughout the body. GB3 accumulation occurs in virtually all cardiac cells (cardiomyocytes, conduction system cells, fibroblasts, and endothelial and smooth muscle vascular cells), ultimately leading to ventricular hypertrophy and fibrosis, heart failure, valve disease, angina, dysrhythmias, cardiac conduction abnormalities, and sudden death. Despite available therapies and supportive treatment, cardiac involvement carries a major prognostic impact, representing the main cause of death in FD. In the last years, knowledge has substantially evolved on the pathophysiological mechanisms leading to cardiac damage, the natural history of cardiac manifestations, the late-onset phenotypes with predominant cardiac involvement, the early markers of cardiac damage, the role of multimodality cardiac imaging on the diagnosis, management and follow-up of Fabry patients, and the cardiac efficacy of available therapies. Herein, we provide a comprehensive and integrated review on the cardiac involvement of FD, at the pathophysiological, anatomopathological, laboratory, imaging, and clinical levels, as well as on the diagnosis and management of cardiac manifestations, their supportive treatment, and the cardiac efficacy of specific therapies, such as enzyme replacement therapy and migalastat.

Proposed stages of Fabry disease: insights from multiparametric cardiac MRI and advanced ECG

Abstract Funding Acknowledgements Type of funding sources: None. Background Staging of Fabry disease (FD) cardiomyopathy uses multiparametric cardiac MRI. Advanced disease is characterized by left ventricular hypertrophy (LVH), myocardial inflammation/oedema (high native T2 mapping) and/or fibrosis (late gadolinium enhancement, LGE). Pre-LVH involvement has been described and includes myocardial sphingolipid storage (low native T1 mapping), impaired LV global longitudinal strain (GLS) and microvascular disease/dysfunction (low stress myocardial blood flow, MBF, in perfusion mapping). We aimed to define (1) the early myocardial phenotype prior to T1 lowering/pre-storage and (2) the stages of cardiac involvement in FD. Methods FD patients and age, sex and heart rate matched healthy controls underwent same-day ECG with advanced analysis and multiparametric CMR (cines, GLS, pre-contrast T1 and T2 mapping, adenosine stress perfusion mapping [for MBF] and LGE). Results 114 Fabry patients (46 ± 13 years, 61% female, 37% [n = 72] had LVH) and 76 controls (49 ± 15 years, 50% female) were included. FD with vs without LVH in brief and as expected, FD with LVH had significantly (p &amp;lt; 0.05) lower MBF, GLS and T1, and higher T2 and %LGE. FD pre-LVH low T1 vs pre-LVH normal T1: low T1 patients (32/72, 44%) had higher LV mass index (67 ± 14 vs 59 ± 10g/m2, P = 0.011), maximum Q wave amplitude (2[1-2] vs 1[1-2]mm, P &amp;lt; 0.001), Sokolow-Lyon index (22[16-28] vs 17[13-23]mm, P = 0.031) and more fractionated QRS complexes (44 vs 18%, P = 0.020). FD pre-LVH normal T1 vs healthy controls: normal T1 pre-LVH Fabry patients (40/72, 56%) had reduced GLS (-18 ± 2 vs -20 ± 2%, P &amp;lt; 0.001), microvascular impairment (lower MBF 2.5 ± 0.7 vs 3.0 ± 0.8mL/g/min, P = 0.028), subtle T2 elevation (50 ± 4 vs 48 ± 2ms, p = 0.027) and limited LGE (%LGE 0.3 ± 1.1 vs 0%, P = 0.004) when compared to healthy controls; ECG abnormalities included shorter P wave duration (88 ± 12 vs 94 ± 15ms, P = 0.010) and T wave peak time (Tonset–Tpeak; 104 ± 28 vs 115 ± 20ms, P = 0.015), resulting in a more symmetric T wave with lower T wave time ratio (Tonset–Tpeak)/(Tpeak–Tend) (1.5 ± 0.4 vs 1.8 ± 0.4, P &amp;lt; 0.001) compared to controls. Conclusion Prior staging of Fabry cardiomyopathy included a pre-LVH stage (accumulation/storage) and two LVH stages (hypertrophy and inflammation; fibrosis and impairment). Here we define an even earlier stage, pre-LVH pre-detectable storage, defined by microvascular dysfunction, impaired GLS and altered atrial depolarization and ventricular repolarization intervals (see Figure). Abstract Figure. Proposed stages of cardiac involvement

Trabecular complexity as an early marker of cardiac involvement in Fabry disease.

Fabry cardiomyopathy is characterized by glycosphingolipid storage and increased myocardial trabeculation has also been demonstrated. This study aimed to explore by cardiac magnetic resonance whether myocardial trabecular complexity, quantified by endocardial border fractal analysis, tracks phenotype evolution in Fabry cardiomyopathy. Study population included 20 healthy controls (12 males, age 32±9) and 45 Fabry patients divided into three groups: 15 left ventricular hypertrophy (LVH)-negative patients with normal T1 (5 males, age 28±13; Group 1); 15 LVH-negative patients with low T1 (9 males, age 33±9.6; Group 2); 15 LVH-positive patients (11 males, age 53.5±9.6; Group 3). Trabecular fractal dimensions (Dfs) (total, basal, mid-ventricular, and apical) were evaluated on cine images. Total Df was higher in all Fabry groups compared to controls, gradually increasing from controls to Group 3 (1.27±0.02 controls vs. 1.29±0.02 Group 1 vs. 1.30±0.02 Group 2 vs. 1.34±0.02 Group 3; P<0.001). Group 3 showed significantly higher values of all Dfs compared to the other Groups. Both basal and total Dfs were significantly higher in Group 1 compared with controls (basal: 1.30±0.03 vs. 1.26±0.04, P=0.010; total: 1.29±0.02 vs. 1.27±0.02, P=0.044). Total Df showed significant correlations with: (i) T1 value (r=-0.569; P<0.001); (ii) LV mass (r=0.664, P<0.001); (iii) trabecular mass (r=0.676; P<0.001); (iv) Mainz Severity Score Index (r=0.638; P<0.001). Fabry cardiomyopathy is characterized by a progressive increase in Df of endocardial trabeculae together with shortening of T1 values. Myocardial trabeculation is increased before the presence of detectable sphingolipid storage, thus representing an early sign of cardiac involvement.

Increased Spread of Native T1 Values Assessed With MRI as a Marker of Cardiac Involvement in Fabry Disease.

OBJECTIVE. Cardiac involvement is the leading cause of mortality in Fabry disease. Noninvasive markers of cardiac involvement are needed to identify patients at high risk. The purpose of this study was to evaluate the diagnostic potential of segmental native T1 spread as an imaging biomarker in Fabry disease. SUBJECTS AND METHODS. In this prospective study, 43 patients with confirmed Fabry disease (mean ± SD age, 46±14 years; 70% women) and 17 healthy control subjects (mean ± SD age, 44 ±13 years; 53% women) underwent 3-T cardiac MRI including modified Look-Locker inversion recovery T1 mapping. Segmental native T1 spread was calculated as the difference between maximum and minimum segmental native T1 values, expressed as an absolute value and as a relative percentage of global native T1. RESULTS. Absolute and relative segmental native T1 spreads were significantly higher in patients with Fabry disease than in healthy control subjects (absolute median, 115 vs 98 ms [p = 0.004]; relative median, 9.9% vs 8.0% [p < 0.001]) and correlated positively with quantitative late gadolinium enhancement (absolute, r = 0.434, p < 0.001; relative, r = 0.436, p < 0.001), indexed left ventricular mass (absolute, r = 0.316, p = 0.01; relative, r = 0.347, p = 0.007), and global longitudinal strain (absolute, r = 0.289, p = 0.03; relative, r = 0.277, p = 0.03). Relative segmental native T1 spread differentiated patients with Fabry disease from healthy control subjects (odds ratio, 1.44 [95% CI, 1.10-1.89]; p = 0.009). Interob-server agreement was excellent for both absolute (intraclass correlation coefficient, 0.932) and relative (intraclass correlation coefficient, 0.926) segmental native T1 spread. CONCLUSION. Increased native T1 spread is a reproducible imaging biomarker of cardiac involvement in Fabry disease and may be particularly useful in the evaluation of patients who cannot undergo late gadolinium enhancement imaging.

The Lysosomal Storage Diseases: A Promising Axis for COVID-19 Future Therapies

Severe acute respiratory syndrome coronavirus 2 (SARSCoV- 2) is the causative agent of the current COVID-19 pandemic; it has been officially named) by the WHO in March 2020 [1]. The current coronavirus pandemic is characterized by high contagion and infection rates and higher mortality among patients with some underlying medical conditions, including those with diabetes, high blood pressure, autoimmune diseases… Caring for high-risk populations is an essential part of managing any communicable disease threat. Patients with inherited metabolic diseases (IMD) are known to be disproportionately affected by respiratory diseases and recurrent infections often resulting in increased morbidity and mortality. IMD, like lysosomal storage diseases (LSD), were included in the group of conditions considered to have an extremely high risk of severe COVID-19 illness [2]. Respiratory symptoms are frequent in patients with LSD with pathomechanisms such as infiltration of pulmonary structures by abnormal cells in Niemann-Pick (NPD) and Gaucher diseases (GD), airway soft tissue infiltration, accompanied by limited chest mobility in mucchopolysaccharidoses diseases (MPSs), dyspnea and wheezing, with a compromised respiratory function by cardiac involvement in Fabry disease (FD) [3]. The hepatosplenomegaly and spinal deformity reduce lung volume in this diseases, it is obvious that a COVID-19 infection will be fa tal for these patients by accelerating respiratory decline. However, few works had addressed this point and few recommendations and practical considerations have been issued by practitioners and experts involved with for the management of this health crisis.

Progressive electrocardiographic changes in parallel with cardiac magnetic resonance findings in fabry disease

Abstract Background Cardiac Magnetic Resonance (CMR) allows to detect progressive stages of cardiac involvement in Fabry Disease (FD). A systematic description of electrocardiographic (ECG) alterations occurring in FD is currently missing. Purpose To explore ECG changes in progressive stages of FD cardiomyopathy. Methods 71 FD patients and 17 healthy controls underwent CMR with T1 mapping and 12-lead ECG. ECG analysis included the duration of the P-wave and the interval between the end of P-wave and the beginning of QRS (PendQ). FD patients in the test cohort were divided into 3 groups with increasing severity of cardiac involvement: A) normal T1, no LVH; B) low T1, no LVH; C) low T1, LVH. Results An increase of Pwave/PendQ ratio was observed in Group A compared to Controls (1.08 vs. 0.75, p&amp;lt;0.0001). Higher Pwave/PendQ ratio (1.50 vs. 1.08, p&amp;lt;0.0001), shorter PQc interval (127.9 vs. 159.5, p=0.0007), increased Sokolow-Lyon Index (SLI) (3.2 vs. 2.4, p&amp;lt;0,001) and T wave amplitude (0.6 vs. 0.4 mV, p=0.002) characterized Group B in comparison with Group A. A higher prevalence of left bundle branch blocks (13.6% vs. 0%, p=0.03) and repolarization abnormalities (77.3% vs. 5.7%), wider QRS (120 vs 95 msec, p&amp;lt;0.0001) and QT (460 vs 400 msec, p=0.003) intervals were found in Group C compared to Group B. SLI (AUC 0.769), Pwave/PendQ (AUC 0.778), QRS (AUC 0.703) and QT (AUC 0.769) durations resulted to be independent predictors of low T1 values on CMR at stepwise multivariate analysis. Conclusion FD is characterized by progressive ECG changes. The identification of ECG parameters able to predict a lowering of myocardial T1 values on CMR may promote early detection of cardiac involvement, helping to target the therapeutic approach. Progressive ECG and CMR changes in FD Funding Acknowledgement Type of funding source: Other. Main funding source(s): This study was partially supported by Ricerca Corrente funding from the Italian Ministry of Health to IRCCS Policlinico San Donato.

P873 A rare and potentially treatable cause of left ventricular hypertrophy

Abstract Introduction A 67-year-old man was referred for care of "asymptomatic hypertrophic cardiomyopathy". He did not have hypertension. No significant positive family history could be elicited. Electrocardiogram showed sinus rhythm with voltage criteria of left ventricular hypertrophy (LVH). Outside Transthoracic Echocardiogram (TTE) reported normal ejection fraction with asymmetric septal hypertrophy without outflow obstruction. He was put on observation for few years and was not any treatment. On first encounter in our clinic, physical examination including skin and eye assessment, and laboratory tests including renal function were unremarkable. Procedure TTE was repeated in our clinic showing normal left ventricular size with ejection fraction 55%, and impaired diastolic relaxation. There was asymmetric septal hypertrophy with septal thickness 2.1 cm (Figure A). There was mild systolic anterior motion of mitral apparatus and mild mitral regurgitation, without resting or Valsalva provoked outflow obstruction. Global longitudinal strain was -7.7% with most prominent abnormalities seen at apex, mid to basal anteroseptal and anterior wall (Figure B). Further assessment by Cardiac MRI showed similar asymmetric septal wall thickening. Late gandolinium enhancement study demonstrated patchy fluffy hyperenhancement of the mid wall of the basal to mid anteroseptal segment, and mid to apical anterior segment, suggestive of myocardial fibrosis (Figure C1 and C2). Dried spot blood was sent to Taiwan for enzyme study which revealed partial acid alpha-galactosidase A deficiency. Further genetic study detected a mutation of Hemizygous NM_000169.2(GLA):c.640-801[G &amp;gt; A] at intron 4. Finally endomyocardial biopsy was done which confirmed the cardiac involvement of Fabry disease (Figure D, myelin body shown under electron microscopy). This gentleman was referred for consideration of Enzyme Replacement Therapy (ERT). Discussion Fabry disease is an X-linked glycolipid storage disease with accumulation of globotriaosylceramide in lysosomes in multiple cell types throughout the body leading to various organ involvement. Cardiac manifestations include unexplained LVH, valvular regurgitation, conduction abnormalities etc. It occurs in up to 0.3-5% of patients with hypertrophic cardiomyopathy. Fabry disease should be considered as a differential diagnosis in all men with sporadic or non-autosomal dominant transmission of unexplained LVH, since treatment with ERT is available which may reduce LVH and improve myocardial function, although any impact on long term outcome has not yet been established. Conclusion This case illustrated a rare but potentially treatable cause of hypertrophic cardiomyopathy. Myocardial strain imaging should be integrated in routine TTE study for assessment of unexplained left ventricular hypertrophy. Multi-modality imaging and multi-specialty approach help in identifying patients of cardiac variant of Fabry disease who may benefit from ERT. Abstract P873 Figure.

Significance of Cardiac Involvement in Fabry Disease

Fabry Disease (FD) is a rare form of progressive genetic disorder, which results on damages to multi-organs especially cardio-renal system [1]. As for the genetic origin, FD is occurred due to the specific mutation of the GLA gene, which is routed on X Chromosome, where currently more than 800 types of different GLA mutations have been reported [1,2].