Search

Background: Peripheral pigmentary changes are common amongst women with Danon disease; however, there is currently a lack of longitudinal observational studies of the retinal changes in this condition, and the long-term visual prognosis is not well understood. Methods and Results: In this report, we present long-term follow-up data (12 years of follow-up) regarding peripheral retinopathy in an Asian woman and her mother who were both diagnosed with Danon disease. Both patients showed a novel nonsense mutation of the LAMP2 gene (c.123 of exon 2). During the follow-up period, no evident extension of peripheral pigmented lesions or visual field progression was observed. Conclusions: We report, for the first time, the long-term longitudinal follow-up of Danon disease-related retinopathy in an Asian patient featuring an indolent macular-sparing peripheral lesion.

Successful therapy in a cohort with early onset Danon disease (DD) highlights the potential importance of earlier disease recognition. We present experience from the largest National Pediatric Center in Russia for cardiomyopathy patients. This report focuses on identification of early clinical features of DD in the pediatric population by detailed pedigree analysis and review of medical records. Nine patients (3 females) were identified with DD at the Russian National Medical Research Center of Children's Health ("National Pediatric Center") aged birth to 16 years. At presentation/evaluation: all patients had left ventricular hypertrophy (LVH), ECG features of Wolff-Parkinson-White (WPW), and an increase in hepatic enzymes (particularly lactate dehydrogenase (LDH)); three had marked increase in NT-proBNP; two had HCM with impaired LV function; one had LVH with LV noncompaction; five had arrhythmia with paroxysmal supraventricular and/or ventricular tachycardia. Two teenagers died at ages 16–17 from refractory heart failure and two underwent heart transplantation. All patients were found to have a pathogenic/likely pathogenic variant in the LAMP2 gene, six patients had no family history and a de novo evolvement was documented in 4/6 of those available for genetic tested. Retrospective review related to family background and earlier clinical evaluations revealed a definitive or highly suspicious family history of DD in 3, early clinical presentation with cardiac abnormalities (ECG, echo) in 3, and cerebral, hepatic and/or neuromuscular symptoms in 5. Abnormalities were detected 9,5 months to 5,8 years, median 3,5 years prior to referral to the National Pediatric Center. The earliest clinical manifestations of Danon disease occur in the first 12 years of life with symptoms of skeletal muscle and cerebral disease, raised hepatic enzymes, and evidence of cardiac disease on ECG/echo. • Danon disease develops in patients of both sexes, despite the X-linked variant of inheritance. • Pediatric red flags for early diagnosis are: intracellular enzyme elevation in blood tests which are associated with Wolff-Parkinson-White-like patterns on ECG and myocardial hypertrophy. • The positive Phase 1 study results of Danon gene therapy treatment makes early diagnosis in children particularly important and might help to avoid the typically rapid progression of Danon disease that leads to patients requiring heart transplantation. [ABSTRACT FROM AUTHOR]

Danon disease is a severe X-linked disorder caused by deficiency of the lysosome-associated membrane protein-2 (LAMP-2). Clinical manifestations are phenotypically diverse and consist of hypertrophic and dilated cardiomyopathies, skeletal myopathy, retinopathy, and intellectual dysfunction. Here, we investigated the metabolic landscape of Danon disease by applying a multi-omics approach and combined structural and functional readouts provided by Raman and atomic force microscopy. Using these tools, Danon patient-derived cardiac tissue, primary fibroblasts, and human induced pluripotent stem cells differentiated into cardiomyocytes (hiPSC-CMs) were analyzed. Metabolic profiling indicated LAMP-2 deficiency promoted a switch toward glycolysis accompanied by rerouting of tryptophan metabolism. Cardiomyocytes’ energetic balance and NAD+/NADH ratio appeared to be maintained despite mitochondrial aging. In turn, metabolic adaption was accompanied by a senescence-associated signature. Similarly, Danon fibroblasts appeared more stress prone and less biomechanically compliant. Overall, shaping of both morphology and metabolism contributed to the loss of cardiac biomechanical competence that characterizes the clinical progression of Danon disease.

The lysosome, a key organelle for cellular clearance, is associated with a wide variety of pathological conditions in humans. Lysosome function and its related pathways are particularly important for maintaining the health of the cardiovascular system. In this review, we highlighted studies that have improved our understanding of the connection between lysosome function and cardiovascular diseases with an emphasis on a recent breakthrough that characterized a unique autophagosome-lysosome fusion mechanism employed by cardiomyocytes through a lysosomal membrane protein LAMP-2B. This finding may impact the development of future therapeutic applications.

This case describes an uncommon acute complication of diffuse thrombotic angiopathy and associated aHUS/TTP in an 11‐year‐old girl with Danon disease who underwent orthotopic heart transplant. Shortly after transplant, despite an uncomplicated operative course, the patient developed severe kidney injury and progressive altered mental status, culminating in cerebral edema, brain herniation, and death. She had received a single dose of tacrolimus (FK506) and a single dose of antithymocyte globulin. Sources of progressive somnolence, including oversedation from impaired renal clearance of opiates, and severe myopathy as has been previously described in Danon disease, were ruled out, and the patient continued to decline. Initial brain CT scan early after transplant showed no signs of cerebral edema, but repeat CT indicated severe cerebral edema. Based on autopsy, diffuse thrombotic angiopathy, with signs of hemolytic anemia with schistocytes, was likely responsible for her deterioration in the broader condition of aHUS/TTP. [ABSTRACT FROM AUTHOR]

Danon disease is a rare and fatal disease caused by a mutation in the lysosome-associated membrane protein 2 gene. Impaired intracellular autophagy causes lysosomal vacuoles to accumulate mainly in myocardial and skeletal muscle cells, leading to hypertrophic cardiomyopathy, skeletal myopathy, and varying degrees of intellectual disability. Two distinct childhood presentations of Danon disease are described in this report.

Rationale Induced pluripotent stem cells (iPSCs) have been generated from patients with various forms of disease, including Danon disease (DD); however, few reports exist regarding disease-specific iPSCs derived from clinically divergent monozygotic twins. Objective We examined the characteristics of iPSCs and iPSC-derived cardiomyocytes (iPSC-CMs) generated from clinically divergent monozygotic female twins with DD. Methods and results We generated iPSCs derived from T-cells isolated from clinically divergent, 18-year-old female twins with DD harboring a mutation in LAMP2 at the intron 6 splice site (IVS6 + 1_4delGTGA). Two divergent populations of iPSCs could prepare from each twin despite of their clinical divergence: one with wild-type LAMP2 expression (WT-iPSCs) and a second with mutant LAMP2 expression (MT-iPSCs). The iPSCs were differentiated into iPSC-CMs and then autophagy failure was observed only in MT-iPSC-CMs by electron microscopy, tandem fluorescent-tagged LC3 analysis, and LC3-II western blotting. Under these conditions, X-chromosome inactivation (XCI) was determined by PCR for the (CAG)n repeat in the androgen receptor gene, revealing an extremely skewed XCI pattern with the inactivated paternal wild-type and maternal mutant X-chromosomes in MT-iPSCs and WT-iPSCs, respectively, from each twin. Conclusion Regardless of their clinical differences, we successfully established two sets of iPSC lines that expressed either wild-type or mutant LAMP2 allele from each monozygotic twin with DD, of which only the populations expressing mutant LAMP2 showed autophagic failure. [ABSTRACT FROM AUTHOR]

Background: Danon disease (DD) is a rare X-linked dominant cardioskeletal myopathy, caused by mutations in the Lysosome-Associated Membrane Protein-2 gene (LAMP-2). The X-linked inheritance causes differences in phenotypic severity between males and female1. Classical clinical features in males include skeletal myopathy, mental retardation, and hypertrophic cardiomyopathy (HCM), while female carriers show a later onset of milder symptoms and an equal prevalence of dilated cardiomyopathy and HCM2. Case report: We report a case of a female patient who first presented in 2015 at the age of 26 years with a transient ischemic attack. Initial echocardiographic assessments revealed typical images of dilated cardiomyopathy with a mildly reduced left ventricular ejection fraction at 45%, a moderately dilated left ventricle (EDD 60 mm) with normal wall thickness (11 mm). Clinically she was NYHA 2 class, her ECG showed sinus rhythm and no paroxysms of atrial fibrillation could be verified, while coronary artery disease was ruled out. Guidelines directed medical therapy was started along with warfarin, and in 2017 a CRT-D was implanted. Over the course of years, her EFLV gradually deteriorated to 25% in 2019, while the dimensions of the left ventricle remained almost the same, with development of severe symptoms (NYHA 3). Genetic analysis, using targeted next generation sequencing, showed that the patient carried a LAMP2 missense variant, c.928G > A, confirming the DD. The patient was included to the heart transplantation waiting list, and in 2020 a successful heart transplantation was performed. Conclusion: Although the DD is typically associated with HCM phenotype, the dilated cardiomyopathy phenotype is also prevalent in women, confirming phenotypic heterogeneity of DD, while genetic testing is essential for diagnosis. [ABSTRACT FROM AUTHOR]

We report a case series of post-operative endophthalmitis due to Pseudomonas aeruginosa. A total of 8 patients operated for cataract, were referred to our facility with acute onset of decreased vision 1-2 days following surgery. All patients had clinical evidence of acute exogenous endophthalmitis with severe anterior chamber exudative reaction. Ocular samples (aqueous aspirate and vitreous tap) for microbiology were taken from all eyes. Microbiology from all revealed P. aeruginosa which was resistant to all antibiotics except colistin. With prompt and accurate microbiological support it was possible to control the infection in all the eyes with the use of colistin intravitreally and intravenously which to the best of our knowledge, has been never reported. Intravitreal injection of colistin could be an option effective in the management of multi-drug-resistant endophthalmitis caused by Gram-negative bacteria.

Danon disease, an X-linked dominant cardioskeletal myopathy, is caused by primary deficiency of lysosome-associated membrane protein-2 (LAMP-2). To clarify the clinicopathological features and management, we performed the first nationwide, questionnaire-based survey on Danon disease in Japan. A total of 39 patients (17 males, 22 females) from 20 families were identified in the analysis. All patients had cardiomyopathy. Of the 21 patients who died, 20 (95%) died of cardiac failure or sudden cardiac arrest. Most patients had hypertrophic cardiomyopathy. Wolf⁻Parkinson⁻White syndrome was present at a comparatively high incidence (54% in males, 22% in females). Only one female patient received a heart transplant, which is the most effective therapy. Histopathologically, all male patients showed autophagic vacuoles with sarcolemmal features in muscle. Half of the probands showed de novo mutations. Male patients showed completely absent LAMP-2 expression in muscle. In contrast, female patients showed decreased LAMP-2 expression, which is suggested to reflect LAMP-2 haploinsufficiency due to a heterozygous null mutation. In conclusion, Danon disease is an extremely rare muscular disorder in Japan. Cardiomyopathy is the most significant prognostic factor and the main cause of death. Our findings suggest that the present survey can extend our understanding of the clinical features of this rare disease.

Introduction Danon disease is an X-linked lysosomal condition that causes a deficiency of lysosome-associated membrane protein 2 (LAMP2) gene. It is characterized clinically by a triad of skeletal myopathy, cardiomyopathy, and intellectual disability. Methods We examined clinical, echocardiographic, and genetic data on 5 patients with Danon disease, highlighting their clinical course and outcomes. Results All patients presented phenotypically with hypertrophic cardiomyopathy and later developed systolic dysfunction. The mean age at diagnosis was 19 years (11–31 years). All patients had diastolic dysfunction (mean e’ of 5 cm/s [3.5–6 cm/s], mean E/e′ of 17 [15–21]). Three patients required cardiac transplantation (ages 15, 27, and 42). Of the two deaths in this group, both were in women. Conclusion We highlight the aggressive cardiac phenotype of Danon disease in our clinical experience with rapid progression to end-stage cardiomyopathy; this progression occurred in both men and women. A timely diagnosis and an early referral for cardiac transplantation is crucial for improved outcomes. [ABSTRACT FROM AUTHOR]

Danon disease (DD) is a rare X-linked disorder caused by loss-of-function mutations in the LAMP2 gene, which encodes lysosome-associated membrane protein. It is characterized by the triad of hypertrophic cardiomyopathy, myopathy, and intellectual disability. Whereas the molecular and pathophysiological mechanisms underlying this disorder have been previously reported and continue to be explored, the cognitive deficits and psychiatric comorbidities manifested in DD remain an understudied topic. We systematically assessed cognitive abilities and psychiatric comorbidities in 13 males and females. Most of the participants in our cohort ( n = 9; 75%) had an IQ score within the normal range, while only one participant had intellectual disability. Participants' performance on the Cognitive Neuropsychiatric Battery (CNB) showed only mildly impaired cognitive abilities in most modules, except in the executive functioning test, which was low compared to healthy controls. Of note, 69% of the participants met criteria for at least one psychiatric disorder, mainly mood and anxiety disorders, occurring alone or in combination in the same patient. The results of the present study challenge earlier reports suggesting that mental retardation is a core constituent in DD. Of importance, it underscores the need to refer Danon patients to psychiatric assessment. [ABSTRACT FROM AUTHOR]

Aims: Different cardiac arrhythmias have been suggested to be associated with Danon disease, e.g. Wolff-Parkinson-White syndrome. However, a systematic electrophysiological investigation of patients with Danon disease is lacking thus far.Methods and Results: Seven patients with Danon disease (4 males, 35.8 ± 10.8 years; 3 females, 51.3 ± 19.9 years) from 3 different families were studied. In all patients, the presence of Danon disease was confirmed by western blot of biopsy material or genetic testing. The patients were characterized by 12-lead electrocardiogram (ECG), Holter ECG, echocardiography, and serial implantable cardioverter defibrillator (ICD) interrogations (in ICD recipients). All male patients underwent electrophysiological investigation (EP study). Asymptomatic ventricular tachyarrhythmias were documented in six of the seven patients. Moreover, 5 of the 7 patients suffered from atrial fibrillation (AF), with 1 of them experiencing thromboembolic stroke at the age of 30 years. In male patients, the initial QRS complex was characterized by a slurring upstroke and shortened PQ interval mimicking ventricular pre-excitation. One male patient showed initial QRS complex slurring with prolonged PR interval. However, the presence of an accessory pathway was excluded by an EP study in all patients. In female patients, initial QRS complex slurring was significantly less distinct. In four patients, ICD implantation was performed for primary prevention of sudden cardiac death. However, sustained ventricular arrhythmias were not documented in any of the patients.Conclusions: The present study indicates that the distinct surface ECG pattern in Danon disease is not associated with ventricular pre-excitation. Atrial fibrillation is frequently observed in these patients and may be associated with thromboembolic events in the young, while sustained ventricular arrhythmias occur less frequently than previously reported. [ABSTRACT FROM AUTHOR]

Danon disease is a rare, X-linked dominant genetic disorder that is caused by defects in the lysosome-associated membrane protein 2 (LAMP2) gene. It manifests predominantly in young males with a classic triad of cardiomyopathy, skeletal myopathy, and intellectual disability. Death from cardiac disease is the ultimate cause of demise in many patients if left untreated. Given the rarity of the condition, the natural history is poorly understood. Here, we present a case report on a 14-year-old Hispanic boy with Danon disease, highlighting major clinical events and diagnostic study findings over a six-year period from age of symptom onset to age of death. He had significant hypertrophic cardiomyopathy (ventricular septal thickness 65 mm) and experienced various arrhythmias during his clinical course including Wolf-Parkinson-White syndrome, non-sustained ventricular tachycardia, and pre-excited atrial fibrillation with a fasciculoventricular anomalous accessory pathway. He had sudden cardiac death from ventricular fibrillation at age 14 and his heart had a weight of 1425 grams at autopsy. We also provide a review of the cardiac Danon disease literature related to diagnostic and management approaches to aid cardiologists in evaluating and treating cardiac manifestations in Danon disease patients. [ABSTRACT FROM AUTHOR]

Background: Cardiac involvement constitutes the primary cause of mortality in patients with Danon disease (DD). This study aimed to explore the cardiac magnetic resonance (CMR) features and progressions of DD cardiomyopathies in a family with long-term follow-up., Methods: Seven patients (five females and two males), belonging to the same family and afflicted with DD, were enrolled in this study between 2017 and 2022. The cardiac structure, function, strain, tissue characteristics on CMR and their evolutions during follow-up were analyzed., Results: Three young female patients (3/7, 42.86%) exhibited normal cardiac morphology. Four patients (4/7, 57.14%) displayed left ventricle hypertrophy (LVH), and mostly with septal thickening (3/4, 75%). A single male case (1/7, 14.3%) showed decreased LV ejection fraction (LVEF). Nonetheless, the global LV strain of the four adult patients decreased in different degree. The global strain of adolescent male patients was decreased compared to the age-appropriate female patients. Five patients (5/7, 71.43%) exhibited late gadolinium enhancement (LGE), with proportion ranging from 31.6% to 59.7% (median value 42.7%). The most common LGE location was the LV free wall (5/5, 100%), followed by right ventricle insertion points (4/5, 80%) and intraventricular septum (2/5, 40%). Segmental radial strain ( r s  = -0.586), circumferential strain ( r  = 0.589), and longitudinal strain ( r  = 0.514) were all moderately correlated with the LGE proportions of corresponding segments ( P  < 0.001). T2 hyperintense and perfusion defect foci were identified, overlapping with the LGE areas. During follow-up, both the young male patients exhibited notable deterioration of their cardiac symptoms and CMR. The LVEF and strain decreased, and the extent of LGE increased year by year. One patient underwent T1 mapping examination. The native T1 value was sensitively elevated even in regions without LGE., Conclusions: Left ventricular hypertrophy, LGE with sparing or relatively less involved IVS, and LV dysfunction are prominent CMR features of Danon cardiomyopathy. Strain and T1 mapping may have advantages in detecting early-stage dysfunction and myocardial abnormalities in DD patients, respectively. Multi-parametric CMR can serve as an optimal instrument for detecting DD cardiomyopathies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Liu, Zhai, Wang, Wang, Jiang, Sun, Chen, Xu, Cui and Li.)

Danon disease, an X-linked multisystemic disorder, is due to deficiency of Lysosome-Associated Membrane Protein 2 (LAMP2). It is usually characterized by hypertrophic cardiomyopathy, mental retardation and skeletal myopathy, sometimes also with atypical features. A 20-year-old man with cognitive impairment was admitted to the Emergency Room because of a sudden chest pain. ECG showed Wolff–Parkinson–White syndrome; echocardiography revealed hypertrophic cardiomyopathy, and, shortly after, he experienced a cardiac arrest followed by an occipital ischemic stroke. On neurological examination, he complained of visual loss, and diffuse muscle wasting and weakness were also unexpectedly noted. Electromyography evidenced a myopathic pattern and a peripheral neuropathy. A muscle biopsy disclosed vacuolar myopathy with glycogen storage; immunohistochemical studies demonstrated a LAMP-2 deficiency. LAMP2 molecular analysis identified a “de novo” mutation (p. Q353X). This patient with a neglected Danon disease, experienced an unusual complication as a stroke due to cerebral hypoperfusion after cardiac arrest caused by WPW syndrome. [ABSTRACT FROM AUTHOR]

Danon disease, primary lysosome-associated membrane protein-2 (LAMP-2) deficiency, is characterized clinically by cardiomyopathy, myopathy and intellectual disability in boys. Because Danon disease is inherited in an X-linked dominant fashion, males are more severely affected than females, who usually have only cardiomyopathy without myopathy or intellectual disability; moreover, the onset of symptoms in females is usually in adulthood. We describe a girl with Danon disease who presented with hypertrophic cardiomyopathy and Wolff-Parkinson-White (WPW) syndrome at 12 years of age. Subsequently, she showed signs of mild learning disability and intellectual disability on psychological examinations. She had a de novo novel mutation in the LAMP-2 gene and harbored an identical c.749C > A (p.Ser250X) variant, resulting in a stop codon in exon 6. She showed decreased, but not completely absent LAMP-2 expression on immunohistochemical and Western blot analyses of a skeletal muscle biopsy specimen, which has been suggested to be caused by a 50% reduction in LAMP-2 expression (LAMP-2 haploinsufficiency) in female patients with Danon disease caused by a heterozygous null mutation. To our knowledge, our patient is one of the youngest female patients to have been given a diagnosis of Danon disease. In addition, this is the first documented case in a girl that was clearly associated with intellectual disability, which is very rare in females with Danon disease. Our findings suggest that studies of female patients with Danon disease can extend our understanding of the clinical features of this rare disease. [ABSTRACT FROM AUTHOR]

A 27-year-old woman developed bilateral acute angle closure glaucoma (AACG) and transient myopia after taking oseltamivir for four days. On the fourth day, she received systemic and topical intraocular pressure (IOP)-lowering agents, and IOP decreased in both eyes. However, her visual acuity was unchanged. A myopic shift of -5.25 D OD and -5.0 D OS was estimated to have occurred in the acute phase. A-scan ultrasonography and Pentacam showed markedly shallow anterior chambers and increased lens thickness. Ultrasound biomicroscopy revealed an annular ciliochoroidal effusion with forward displacement of the lens-iris diaphragm. Ciliochoroidal effusion and transient myopia were resolved after discontinuation of oseltamivir.

Ocular manifestations of Noonan syndrome (NS) in a set of healthy 20-year-old African-American fraternal twins are reported with emphasis on a rare finding of keratoconus with acute corneal hydrops in one twin. Both the twins had learning disabilities and attended a special needs school. Evaluation included visual acuity assessment, tonometry and external eye, slit lamp and dilated fundus examinations, topography with Pentacam and external photographs. The first case was more remarkable as keratoconus with acute corneal hydrops was observed. The patient presented with severe cloudy vision that had worsened over a span of 1 month. It improved significantly on follow-up. The second case included a unique constellation of ocular pathology that highlights the diversity of NS manifestations even amongst twins. Conservative treatment of keratoconus with acute corneal hydrops in a NS patient helped largely resolve the patient′s condition. We report the diverse spectrum of ocular manifestations associated with this rare congenital disorder.

To report a patient with Danon retinopathy with cystoid macular edema treated with topical dorzolamide 2% eye drops and oral acetazolamide. A 37-year-old Caucasian man with Danon disease treated with topical and oral carbonic anhydrase inhibitors participated in the study. Examinations performed before and during treatment included visual acuity (VA), spectral-domain optical coherence tomography, and electroretinography. Following total 48 weeks of treatment, VA decreased from 20/30 OD, 20/200 OS, to 20/40 OD, CF OS. The mean central retinal thickness was unchanged from baseline 263 μm OD , 226 μm OS, after treatment 283 μm OD and 202 μm OS. In our case, carbonic anydrase inhibitors were not effective. However, a general recommendation cannot be given based on a single case.

Part time occlusion therapy is not reported to cause occlusion (reverse) amblyopia. However, when combined with high dose oral levodopa, an increase in the plasticity of the visual cortex can lead to occlusion amblyopia. In this case report, we describe a six year old child who developed occlusion amblyopia following part time patching combined with oral levodopa.

Danon disease (DD) is an X-linked multisystem disorder with clinical features characterized by the triad of hypertrophic cardiomyopathy, skeletal muscle weakness, and mental retardation. Cardiac involvement can be fatal in the absence of an effective treatment option such as heart transplantation. Molecular studies have proved that LAMP-2 protein deficiency, mainly LAMP-2B isoform, resulting from LAMP2 gene mutation, is the culprit for DD. Autophagy impairment due to LAMP-2 deficiency mediated the accumulation of abnormal autophagic vacuoles in cells. While it is not ideal for mimicking DD phenotypes in humans, the emergence of LAMP-2-deficient animal models and induced pluripotent stem cells from DD patients provided powerful tools for exploring DD mechanism. In both in vitro and in vivo studies, much evidence has demonstrated that mitochondria dysfunction and fragmentation can result in DD pathology. Fundamental research contributes to the therapeutic transformation. By targeting the molecular core, several potential therapies have demonstrated promising results in partial phenotypes improvement. Among them, gene therapies anticipate inaugurate a class of symptom control and prevention drugs as their in vivo effects are promising, and one clinical trial is currently underway., (Copyright © 2021. Published by Elsevier Inc.)

Danon disease, a rare glycogen storage disease, is a dominant X-linked disorder. It is due to mutation in gene for lysosome-associated membrane protein 2 (LAMP 2). The LAMP 2 gene is located on Xq24, and its mutation causes primary deficiency of LAMP 2 and myocyte hypertrophy by accumulations of vacuoles containing glycogen. Danon disease is clinically characterized by the triad of hypertrophic cardiomyopathy (HCM), proximal myopathy and mental retardation. Myopathy and mental retardation can be absent, and cardiomyopathy is usually hypertrophic. This is a case report of the patient with genetically confirmed Danon disease and mixed cardiomyopathy, but without myopathy and mental retardation. ECG showed typical Wolff-Parkinson-White (WPW) pattern while echocardiography demonstrated hypertrophy and dilatation of all cardiac chambers with impaired systolic and diastolic function. Male sex, early onset of symptoms, massive hypertrophy of the myocardium and ventricular preexcitation indicate a genetic basis for HCM. Therapeutic measures, except heart transplantation, do not improve prognosis substantially. Only an accurate diagnosis in patients with unexplained HCM helps in establishing of the appropriate treatment strategies and adequate genetic consultation. .