ABSTRACT
AIMS: Recent-onset dilated cardiomyopathy (RODCM) is characterized by heterogeneous aetiology and diverse clinical outcomes, with scarce data on genotype-phenotype correlates. Our aim was to correlate individual RODCM genotypes with left ventricular reverse remodelling (LVRR) and clinical outcomes. METHODS AND RESULTS: In this prospective study, a total of 386 Czech RODCM patients with symptom duration ≤6 months underwent genetic counselling and whole-exome sequencing (WES). The presence of pathogenic (class 5) or likely pathogenic (class 4) variants in a set of 72 cardiomyopathy-related genes was correlated with the occurrence of all-cause death, heart transplantation, or implantation of a ventricular assist device (primary outcome) and/or ventricular arrhythmia event (secondary outcome). LVRR was defined as an improvement of left ventricular ejection fraction to >50% or ≥10% absolute increase, with a left ventricular end-diastolic diameter ≤33 mm/m2 or ≥10% relative decrease. Median follow-up was 41 months. RODCM was familial in 98 (25%) individuals. Class 4-5 variants of interest (VOIs) were identified in 125 (32%) cases, with 69 (18%) having a single titin-truncating variant (TTNtv) and 56 (14%) having non-titin (non-TTN) VOIs. The presence of class 4-5 non-TTN VOIs, but not of TTNtv, heralded a lower probability of 12-month LVRR and proved to be an independent baseline predictor both of the primary and the secondary outcome. The negative result of genetic testing was a strong protective baseline variable against occurrence of life-threatening ventricular arrhythmias. Detection of class 4-5 VOIs in genes coding nuclear envelope proteins was another independent predictor of both study outcomes at baseline and also of life-threatening ventricular arrhythmias after 12 months. Class 4-5 VOIs of genes coding cytoskeleton were associated with an increased risk of life-threatening ventricular arrhythmias after baseline assessment. A positive family history of dilated cardiomyopathy alone only related to a lower probability of LVRR at 12 months and at the final follow-up. CONCLUSIONS: RODCM patients harbouring class 4-5 non-TTN VOIs are at higher risk of progressive heart failure and life-threatening ventricular arrhythmias. Genotyping may improve their early risk stratification at baseline assessment.
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Cholesterol plays an important biological role in the body, and its disruption in homeostasis and synthesis has been implicated in several diseases. Mapping the locations of cholesterol is crucial for gaining a better understanding of these conditions. Silver deposition has proven to be an effective method for analyzing cholesterol using mass spectrometry imaging (MSI). We optimized and evaluated thermal evaporation as an alternative deposition technique to sputtering for silver deposition in MSI of cholesterol. A silver layer with a thickness of 6 nm provided an optimal combination of cholesterol signal intensity and mass resolution. The deposition of an ultrathin nanofilm of silver enabled high-resolution MSI with a pixel size of 10 µm. We used this optimized method to visualize the distribution of cholesterol in the senile plaques in the brains of APP/PS1 mice, a model that resembles Alzheimer's disease pathology. We found that cholesterol was evenly distributed across the frontal cortex tissue, with no evidence of plaque-like accumulation. Additionally, we investigated the presence and distribution of cholesterol in myocardial sections of a human heart affected by wild-type ATTR amyloidosis. We identified the presence of cholesterol in areas with amyloid deposition, but complete colocalization was not observed.
Subject(s)
Cholesterol , Silver , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Animals , Cholesterol/analysis , Cholesterol/chemistry , Silver/chemistry , Humans , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Mice , Mice, Transgenic , Plaque, Amyloid , Brain/metabolism , Brain/diagnostic imaging , Myocardium/metabolism , Myocardium/chemistry , Myocardium/pathology , Amyloidosis/metabolism , Amyloidosis/pathology , Volatilization , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , TemperatureABSTRACT
INTRODUCTION AND OBJECTIVES: Limited information is available on the safety of pregnancy in patients with genetic dilated cardiomyopathy (DCM) and in carriers of DCM-causing genetic variants without the DCM phenotype. We assessed cardiac, obstetric, and fetal or neonatal outcomes in this group of patients. METHODS: We studied 48 women carrying pathogenic or likely pathogenic DCM-associated variants (30 with DCM and 18 without DCM) who had 83 pregnancies. Adverse cardiac events were defined as heart failure (HF), sustained ventricular tachycardia, ventricular assist device implantation, heart transplant, and/or maternal cardiac death during pregnancy, or labor and delivery, and up to the sixth postpartum month. RESULTS: A total of 15 patients, all with DCM (31% of the total cohort and 50% of women with DCM) experienced adverse cardiac events. Obstetric and fetal or neonatal complications were observed in 14% of pregnancies (10 in DCM patients and 2 in genetic carriers). We analyzed the 30 women who had been evaluated before their first pregnancy (12 with overt DCM and 18 without the phenotype). Five of the 12 (42%) women with DCM had adverse cardiac events despite showing NYHA class I or II before pregnancy. Most of these women had a history of cardiac events before pregnancy (80%). Among the 18 women without phenotype, 3 (17%) developed DCM toward the end of pregnancy. CONCLUSIONS: Cardiac complications during pregnancy and postpartum were common in patients with genetic DCM and were primarily related to HF. Despite apparently good tolerance of pregnancy in unaffected genetic carriers, pregnancy may act as a trigger for DCM onset in a subset of these women.
ABSTRACT
BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is associated with accumulation of ATTR amyloid deposits in the heart and commonly manifests as progressive cardiomyopathy. Patisiran, an RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this phase 3, double-blind, randomized trial, we assigned patients with hereditary, also known as variant, or wild-type ATTR cardiac amyloidosis, in a 1:1 ratio, to receive patisiran (0.3 mg per kilogram of body weight) or placebo once every 3 weeks for 12 months. A hierarchical procedure was used to test the primary and three secondary end points. The primary end point was the change from baseline in the distance covered on the 6-minute walk test at 12 months. The first secondary end point was the change from baseline to month 12 in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score (with higher scores indicating better health status). The second secondary end point was a composite of death from any cause, cardiovascular events, and change from baseline in the 6-minute walk test distance over 12 months. The third secondary end point was a composite of death from any cause, hospitalizations for any cause, and urgent heart failure visits over 12 months. RESULTS: A total of 360 patients were randomly assigned to receive patisiran (181 patients) or placebo (179 patients). At month 12, the decline in the 6-minute walk distance was lower in the patisiran group than in the placebo group (Hodges-Lehmann estimate of median difference, 14.69 m; 95% confidence interval [CI], 0.69 to 28.69; P = 0.02); the KCCQ-OS score increased in the patisiran group and declined in the placebo group (least-squares mean difference, 3.7 points; 95% CI, 0.2 to 7.2; P = 0.04). Significant benefits were not observed for the second secondary end point. Infusion-related reactions, arthralgia, and muscle spasms occurred more often among patients in the patisiran group than among those in the placebo group. CONCLUSIONS: In this trial, administration of patisiran over a period of 12 months resulted in preserved functional capacity in patients with ATTR cardiac amyloidosis. (Funded by Alnylam Pharmaceuticals; APOLLO-B ClinicalTrials.gov number, NCT03997383.).
Subject(s)
Amyloidosis , Cardiomyopathies , Prealbumin , RNA, Small Interfering , Humans , Cardiomyopathies/drug therapy , Cardiomyopathies/etiology , Cardiomyopathies/genetics , Cardiomyopathies/metabolism , Prealbumin/genetics , Prealbumin/metabolism , RNA, Small Interfering/therapeutic use , Amyloidosis, Familial/complications , Amyloidosis, Familial/drug therapy , Amyloidosis, Familial/genetics , Liver/metabolism , Double-Blind Method , Amyloidosis/complications , Amyloidosis/drug therapy , Amyloidosis/geneticsABSTRACT
AIMS: Fabry disease (FD) is a rare X-linked genetic disorder caused by α-galactosidase A (AGALA) deficiency. Whereas 'classic' variant has multisystemic manifestation, the more recently described 'later-onset' variant is characterized by predominant cardiac involvement that often mimics hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: Consecutive unrelated patients with HCM were screened for FD in 16 (out of 17) cardiac centres in the Czech Republic covering specialized cardiology care from June 2017 to December 2018. AGALA activity and globotriaosylsphingosine (lyso-Gb3 ) levels were measured in all subjects using the dry blood spot method. FD was suspected in male patients with AGALA activity <1.2 µmol/h/L and in females with either low AGALA activity or lyso-Gb3 > 3.5 ng/mL. Positive screening results were confirmed by genetic testing. We evaluated 589 patients (390 males, 66%) with HCM (mean maximal myocardial thickness 19.1 ± 4.3 mm). The average age was 58.4 ± 14.7 years. In total, 17 patients (11 males, 6 females) had a positive screening result, and subsequently, six of them (four males and two females) had a genetically confirmed pathogenic GLA mutation (total prevalence of 1.02%). Five of these patients were carrying the p.N215S mutation known to cause a typical later-onset cardiac FD. CONCLUSIONS: We confirmed the prevalence of FD repeatedly reported in previous screening programmes (approximately 1% irrespective of gender) in a non-selected HCM population in Central Europe. Our findings advocate a routine screening for FD in all adult patients with HCM phenotype including both genders. The dry blood spot method used led to identification of clearly pathogenic variants.
Subject(s)
Cardiomyopathy, Hypertrophic , Fabry Disease , Female , Humans , Male , alpha-Galactosidase/genetics , Cardiomyopathy, Hypertrophic/diagnosis , Cardiomyopathy, Hypertrophic/epidemiology , Cardiomyopathy, Hypertrophic/genetics , Czech Republic/epidemiology , Fabry Disease/diagnosis , Fabry Disease/epidemiology , Fabry Disease/genetics , Genetic Testing , Adult , Middle Aged , AgedABSTRACT
BACKGROUND: Variants in myosin heavy chain 7 (MYH7) are responsible for disease in 1% to 5% of patients with dilated cardiomyopathy (DCM); however, the clinical characteristics and natural history of MYH7-related DCM are poorly described. OBJECTIVES: We sought to determine the phenotype and prognosis of MYH7-related DCM. We also evaluated the influence of variant location on phenotypic expression. METHODS: We studied clinical data from 147 individuals with DCM-causing MYH7 variants (47.6% female; 35.6 ± 19.2 years) recruited from 29 international centers. RESULTS: At initial evaluation, 106 (72.1%) patients had DCM (left ventricular ejection fraction: 34.5% ± 11.7%). Median follow-up was 4.5 years (IQR: 1.7-8.0 years), and 23.7% of carriers who were initially phenotype-negative developed DCM. Phenotypic expression by 40 and 60 years was 46% and 88%, respectively, with 18 patients (16%) first diagnosed at <18 years of age. Thirty-six percent of patients with DCM met imaging criteria for LV noncompaction. During follow-up, 28% showed left ventricular reverse remodeling. Incidence of adverse cardiac events among patients with DCM at 5 years was 11.6%, with 5 (4.6%) deaths caused by end-stage heart failure (ESHF) and 5 patients (4.6%) requiring heart transplantation. The major ventricular arrhythmia rate was low (1.0% and 2.1% at 5 years in patients with DCM and in those with LVEF of ≤35%, respectively). ESHF and major ventricular arrhythmia were significantly lower compared with LMNA-related DCM and similar to DCM caused by TTN truncating variants. CONCLUSIONS: MYH7-related DCM is characterized by early age of onset, high phenotypic expression, low left ventricular reverse remodeling, and frequent progression to ESHF. Heart failure complications predominate over ventricular arrhythmias, which are rare.
Subject(s)
Cardiomyopathy, Dilated , Heart Failure , Myosin Heavy Chains , Adolescent , Adult , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/epidemiology , Arrhythmias, Cardiac/genetics , Cardiac Myosins/genetics , Cardiomyopathy, Dilated/genetics , Female , Heart Failure/complications , Heart Failure/genetics , Humans , Male , Middle Aged , Myosin Heavy Chains/genetics , Phenotype , Ventricular Remodeling/genetics , Young AdultABSTRACT
Background: Pheochromocytoma is a neuroendocrine tumour originating from the chromaffin cells of adrenal glands or sympathetic paraganglia. It produces most frequently norepinephrine, epinephrine, and dopamine. As a result of non-specific and variable clinical presentation, pheochromocytoma is difficult to diagnose. Case summary: A 37-year-old female without medical history and 57-year-old male patient with diabetes, arterial hypertension, and aortic valve replacement with a mechanical prosthesis were admitted to the hospital after successful cardiopulmonary resuscitation due to ventricular fibrillation. In both patients, coronary angiography demonstrated a normal finding, and echocardiography showed left ventricular (LV) contractile dysfunction with improvement in the subsequent examination. In the first patient, the diagnosis of stress-induced cardiomyopathy was considered as the most probable cause. She was later admitted to hospital due to acute pulmonary oedema with hypertensive crisis. Echocardiography documented reversible LV systolic dysfunction with improvement after 3 days. The course of hospitalization of the male was complicated by multi-organ dysfunction syndrome comprising renal failure, paralytic ileus, and pancreatic irritation, which normalized after 2 weeks. The diagnosis of pheochromocytoma was confirmed by laboratory tests and imaging methods. After pharmacological pre-treatment with doxazosin in both patients and bisoprolol in the female, successful adrenalectomies were performed with no relapse of tumour. Discussion: We describe an atypical clinical presentation of pheochromocytoma with initial cardiac arrest due to ventricular fibrillation and reversible LV systolic dysfunction. Our cases underline that clinical suspicion of pheochromocytoma as a potentially correctable cause should be raised in unexplained cases of severe heart failure, ventricular arrhythmias, and cardiac arrest.
ABSTRACT
BACKGROUND: Implantation of left-ventricular assist systems (LVASs) has become the standard of care for advanced heart failure (HF). The absence of pulsatility in previous devices contributes to vascular and endothelial dysfunction related to atherosclerotic or vascular complications. We hypothesized that the artificial pulsatility provided by the HeartMate 3 (HM3) (Abbott, Chicago, IL) LVAS would exert a favourable effect on the vasculature. METHODS: In 32 patients implanted with HM3 (5 female patients, mean age 55 ± 13.6 years), the reactive hyperemia index (RHI) and peripheral augmentation index (AI), markers of endothelial function and arterial stiffness, were measured with an EndoPAT2000 before and in the third and sixth month after implantation. RHI and AI data from 30 HeartMate II (HM II) (Abbott) recipients in the third and sixth month after implantation, from 15 patients with advanced HF without LVASs and from 13 healthy volunteers were also analyzed. RESULTS: In HM3 recipients, the mean RHI significantly decreased at 3 and 6 months after implantation. The RHI was substantially lower at baseline than that of healthy or the HF reference group. Increasing AI values, indicating worsening arterial stiffness, were also observed. Similar trends were observed in HM II recipients between the third and sixth months but with higher absolute values of RHI and AI. CONCLUSIONS: We detected impaired vascular function in HM3 patients and provided additional evidence on the negative effect of low pulsatility on vascular function after LVAS implantation. The results suggest that the artificial pulsatility of the HM3 does not avert the progression of endothelial dysfunction.
Subject(s)
Arteries/physiopathology , Endothelium, Vascular/physiopathology , Heart Failure/therapy , Heart Ventricles/physiopathology , Heart-Assist Devices , Vascular Resistance/physiology , Ventricular Function, Left/physiology , Female , Follow-Up Studies , Heart Failure/physiopathology , Humans , Male , Middle Aged , Prospective Studies , Time FactorsABSTRACT
AIMS: Dilated cardiomyopathy (DCM) associated with dystrophin gene (DMD) mutations in individuals with mild or absent skeletal myopathy is often indistinguishable from other DCM forms. We sought to describe the phenotype and prognosis of DMD associated DCM in DMD mutation carriers without severe skeletal myopathy. METHODS AND RESULTS: At 26 European centres, we retrospectively collected clinical characteristics and outcomes of 223 DMD mutation carriers (83% male, 33 ± 15 years). A total of 112 individuals (52%) had DCM at first evaluation [n = 85; left ventricular ejection fraction (LVEF) 34 ± 11.2%] or developed DCM (n = 27; LVEF 41.3 ± 7.5%) after a median follow-up of 96 months (interquartile range 5-311 months). DCM penetrance was 45% in carriers older than 40 years. DCM appeared earlier in males and was independent of the type of mutation, presence of skeletal myopathy, or elevated serum creatine kinase levels. Major adverse cardiac events (MACE) occurred in 22% individuals with DCM, 18% developed end-stage heart failure and 9% sudden cardiac death or equivalent. Skeletal myopathy was not associated with survival free of MACE in patients with DCM. Decreased LVEF and increased left ventricular end-diastolic diameter at baseline were associated with MACE. Individuals without DCM had favourable prognosis without MACE or death during follow-up. CONCLUSIONS: DMD-associated DCM without severe skeletal myopathy is characterized by incomplete penetrance but high risk of MACE, including progression to end-stage heart failure and ventricular arrhythmias. DCM onset is the major determinant of prognosis with similar survival regardless of the presence of skeletal myopathy.
Subject(s)
Cardiomyopathy, Dilated , Heart Failure , Muscular Diseases , Adolescent , Adult , Cardiomyopathy, Dilated/epidemiology , Cardiomyopathy, Dilated/genetics , Dystrophin/genetics , Female , Heart Failure/epidemiology , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Stroke Volume , Ventricular Function, Left , Young AdultABSTRACT
PURPOSE: Danon disease (DD) is a rare X-linked disorder caused by pathogenic variants in LAMP2. DD primarily manifests as a severe cardiomyopathy. An early diagnosis is crucial for patient survival. The aim of the study was to determine the usefulness of ocular examination for identification of DD. METHODS: Detailed ocular examination in 10 patients with DD (3 males, 7 females) and a 45-year-old asymptomatic female somatic mosaic carrier of a LAMP2 disease-causing variant. RESULTS: All patients with manifest cardiomyopathy had pigmentary retinopathy with altered autofluorescence and diffuse visual field loss. Best corrected visual acuity (BCVA) was decreased (<0.63) in 8 (40%) out of 20 eyes. The severity of retinal pathology increased with age, resulting in marked cone-rod involvement overtime. Spectral-domain optical coherence tomography in younger patients revealed focal loss of photoreceptors, disruption and deposition at the retinal pigment epithelium/Bruch's membrane layer (corresponding to areas of marked increased autofluorescence), and hyperreflective foci in the outer nuclear layer. Cystoid macular oedema was seen in one eye. In the asymptomatic female with somatic mosaicism, the BCVA was 1.0 bilaterally. An abnormal autofluorescence pattern in the left eye was present; while full-field electroretinography was normal. CONCLUSIONS: Detailed ocular examination may represent a sensitive and quick screening tool for the identification of carriers of LAMP2 pathogenic variants, even in somatic mosaicism. Hence, further investigation should be undertaken in all patients with pigmentary retinal dystrophy as it may be a sign of a life-threatening disease.
Subject(s)
Gene Expression Regulation , Glycogen Storage Disease Type IIb/complications , Lysosomal-Associated Membrane Protein 2/genetics , Retinal Pigment Epithelium/pathology , Retinitis Pigmentosa/diagnosis , Visual Acuity , Adult , Electroretinography , Female , Glycogen Storage Disease Type IIb/diagnosis , Glycogen Storage Disease Type IIb/genetics , Humans , Lysosomal-Associated Membrane Protein 2/biosynthesis , Pedigree , RNA/genetics , Retinitis Pigmentosa/etiology , Retinitis Pigmentosa/genetics , Tomography, Optical Coherence/methods , Young AdultABSTRACT
BACKGROUND: Cardiac muscle hypercontractility is a key pathophysiological abnormality in hypertrophic cardiomyopathy, and a major determinant of dynamic left ventricular outflow tract (LVOT) obstruction. Available pharmacological options for hypertrophic cardiomyopathy are inadequate or poorly tolerated and are not disease-specific. We aimed to assess the efficacy and safety of mavacamten, a first-in-class cardiac myosin inhibitor, in symptomatic obstructive hypertrophic cardiomyopathy. METHODS: In this phase 3, randomised, double-blind, placebo-controlled trial (EXPLORER-HCM) in 68 clinical cardiovascular centres in 13 countries, patients with hypertrophic cardiomyopathy with an LVOT gradient of 50 mm Hg or greater and New York Heart Association (NYHA) class II-III symptoms were assigned (1:1) to receive mavacamten (starting at 5 mg) or placebo for 30 weeks. Visits for assessment of patient status occurred every 2-4 weeks. Serial evaluations included echocardiogram, electrocardiogram, and blood collection for laboratory tests and mavacamten plasma concentration. The primary endpoint was a 1·5 mL/kg per min or greater increase in peak oxygen consumption (pVO2) and at least one NYHA class reduction or a 3·0 mL/kg per min or greater pVO2 increase without NYHA class worsening. Secondary endpoints assessed changes in post-exercise LVOT gradient, pVO2, NYHA class, Kansas City Cardiomyopathy Questionnaire-Clinical Summary Score (KCCQ-CSS), and Hypertrophic Cardiomyopathy Symptom Questionnaire Shortness-of-Breath subscore (HCMSQ-SoB). This study is registered with ClinicalTrials.gov, NCT03470545. FINDINGS: Between May 30, 2018, and July 12, 2019, 429 adults were assessed for eligibility, of whom 251 (59%) were enrolled and randomly assigned to mavacamten (n=123 [49%]) or placebo (n=128 [51%]). 45 (37%) of 123 patients on mavacamten versus 22 (17%) of 128 on placebo met the primary endpoint (difference +19·4%, 95% CI 8·7 to 30·1; p=0·0005). Patients on mavacamten had greater reductions than those on placebo in post-exercise LVOT gradient (-36 mm Hg, 95% CI -43·2 to -28·1; p<0·0001), greater increase in pVO2 (+1·4 mL/kg per min, 0·6 to 2·1; p=0·0006), and improved symptom scores (KCCQ-CSS +9·1, 5·5 to 12·7; HCMSQ-SoB -1·8, -2·4 to -1·2; p<0·0001). 34% more patients in the mavacamten group improved by at least one NYHA class (80 of 123 patients in the mavacamten group vs 40 of 128 patients in the placebo group; 95% CI 22·2 to 45·4; p<0·0001). Safety and tolerability were similar to placebo. Treatment-emergent adverse events were generally mild. One patient died by sudden death in the placebo group. INTERPRETATION: Treatment with mavacamten improved exercise capacity, LVOT obstruction, NYHA functional class, and health status in patients with obstructive hypertrophic cardiomyopathy. The results of this pivotal trial highlight the benefits of disease-specific treatment for this condition. FUNDING: MyoKardia.
Subject(s)
Benzylamines/therapeutic use , Cardiac Myosins/antagonists & inhibitors , Cardiomyopathy, Hypertrophic/drug therapy , Uracil/analogs & derivatives , Adrenergic beta-Antagonists/therapeutic use , Aged , Benzylamines/adverse effects , Calcium Channel Blockers/therapeutic use , Cardiomyopathy, Hypertrophic/physiopathology , Cardiovascular Agents/therapeutic use , Double-Blind Method , Exercise Tolerance/physiology , Female , Hemodynamics/physiology , Humans , Male , Middle Aged , Oxygen Consumption/physiology , Patient Outcome Assessment , Uracil/adverse effects , Uracil/therapeutic useABSTRACT
AIMS: Danon disease (DD) is a rare X-linked disorder caused by mutations in the lysosomal-associated membrane protein type 2 gene (LAMP2). DD is difficult to distinguish from other causes of dilated or hypertrophic cardiomyopathy (HCM) in female patients. As DD female patients regularly progress into advanced heart failure (AHF) aged 20-40 years, their early identification is critical to improve patient survival and facilitate genetic counselling. In this study, we evaluated the prevalence of DD among female patients with non-ischemic cardiomyopathy, who reached AHF and were younger than 40 years. METHODS AND RESULTS: The study cohort comprised 60 female patients: 47 (78%) heart transplant recipients, 2 (3%) patients treated with ventricular assist device, and 11 (18%) patients undergoing pre-transplant assessment. Aetiology of the cardiomyopathy was known in 15 patients (including two DD patients). LAMP2 expression in peripheral white blood cells (WBC) was tested by flow cytometry (FC) in the remaining 45 female patients. Whole exome sequencing was used as an alternative independent testing method to FC. Five additional female DD patients (two with different novel LAMP2 mutations) were identified by FC. The total prevalence of DD in this cohort was 12%. HCM phenotype (57% vs. 9%, * P = 0.022) and delta waves identified by electrocardiography (43% vs. 0%, ** P = 0.002) were significantly more frequent in DD female patients. CONCLUSIONS: Danon disease is an underdiagnosed cause of AHF in young female patients. LAMP2 expression testing in peripheral WBCs by FC can be used as an effective screening/diagnostic tool to identify DD in this patient population.
Subject(s)
Cardiomyopathy, Hypertrophic , Glycogen Storage Disease Type IIb , Heart Failure , Cardiomyopathy, Hypertrophic/complications , Cardiomyopathy, Hypertrophic/diagnosis , Cardiomyopathy, Hypertrophic/epidemiology , Female , Glycogen Storage Disease Type IIb/complications , Glycogen Storage Disease Type IIb/diagnosis , Glycogen Storage Disease Type IIb/epidemiology , Heart Failure/diagnosis , Heart Failure/epidemiology , Heart Failure/etiology , Humans , Lysosomal-Associated Membrane Protein 2/genetics , PhenotypeABSTRACT
Background: The pleomorphic clinical presentation makes the diagnosis of desminopathy difficult. We aimed to describe the prevalence, phenotypic expression, and mitochondrial function of individuals with putative disease-causing desmin (DES) variants identified in patients with an unexplained etiology of cardiomyopathy. Methods: A total of 327 Czech patients underwent whole exome sequencing and detailed phenotyping in probands harboring DES variants. Results: Rare, conserved, and possibly pathogenic DES variants were identified in six (1.8%) probands. Two DES variants previously classified as variants of uncertain significance (p.(K43E), p.(S57L)), one novel DES variant (p.(A210D)), and two known pathogenic DES variants (p.(R406W), p.(R454W)) were associated with characteristic desmin-immunoreactive aggregates in myocardial and/or skeletal biopsy samples. The individual with the novel DES variant p.(Q364H) had a decreased myocardial expression of desmin with absent desmin aggregates in myocardial/skeletal muscle biopsy and presented with familial left ventricular non-compaction cardiomyopathy (LVNC), a relatively novel phenotype associated with desminopathy. An assessment of the mitochondrial function in four probands heterozygous for a disease-causing DES variant confirmed a decreased metabolic capacity of mitochondrial respiratory chain complexes in myocardial/skeletal muscle specimens, which was in case of myocardial succinate respiration more profound than in other cardiomyopathies. Conclusions: The presence of desminopathy should also be considered in individuals with LVNC, and in the differential diagnosis of mitochondrial diseases.
ABSTRACT
Cullin 4B (CUL4B), lysosomal-associated membrane protein Type 2 (LAMP2), ATP1B4, TMEM255A, and ZBTB33 are neighboring genes on Xq24. Mutations in CUL4B result in Cabezas syndrome (CS). Male CS patients present with dysmorphic, neuropsychiatric, genitourinary, and endocrine abnormalities. Heterozygous CS females are clinically asymptomatic. LAMP2 mutations cause Danon disease (DD). Cardiomyopathy is a dominant feature of DD present in both males and heterozygous females. No monogenic phenotypes have been associated with mutations in ATP1B4, TMEM255A, and ZBTB33 genes. To facilitate diagnostics and counseling in CS and DD families, we present a female DD patient with a de novo Alu-mediated Xq24 rearrangement causing a deletion encompassing CUL4B, LAMP2, and also the other three neighboring genes. Typical to females heterozygous for CUL4B mutations, the patient was CS asymptomatic, however, presented with extremely skewed X-chromosome inactivation (XCI) ratios in peripheral white blood cells. As a result of the likely selection against CUL4B deficient clones, only minimal populations (~3%) of LAMP2 deficient leukocytes were identified by flow cytometry. On the contrary, myocardial LAMP2 protein expression suggested random XCI. We demonstrate that contiguous CUL4B and LAMP2 loss-of-function copy number variations occur and speculate that male patients carrying similar defects could present with features of both CS and DD.
Subject(s)
Cullin Proteins/genetics , Glycogen Storage Disease Type IIb/genetics , Lysosomal-Associated Membrane Protein 2/genetics , Mental Retardation, X-Linked/genetics , Adult , Alu Elements/genetics , Cardiomyopathies/genetics , Cardiomyopathies/physiopathology , Chromosome Deletion , DNA Copy Number Variations/genetics , Exons/genetics , Female , Glycogen Storage Disease Type IIb/diagnosis , Glycogen Storage Disease Type IIb/physiopathology , Humans , Loss of Function Mutation/genetics , Male , Mental Retardation, X-Linked/physiopathology , Myocardium/metabolism , Sodium-Potassium-Exchanging ATPase/genetics , Transcription Factors/genetics , X Chromosome Inactivation/geneticsABSTRACT
AIMS: Recent-onset dilated cardiomyopathy (RODCM) is a disease of heterogeneous aetiology and clinical outcome. In this pilot study, we aimed to assess its genetic architecture and correlate genotype with left ventricular reverse remodelling (LVRR). PATIENTS AND METHODS: In this multi-centre prospective observational study, we enrolled 83 Moravian patients with RODCM and a history of symptoms of less than 6 months, for whole-exome sequencing (WES). All patients underwent 12-month clinical and echocardiographic follow-up. LVRR was defined as an absolute increase in left ventricular ejection fraction > 10% accompanied by a relative decrease of left ventricular end-diastolic diameter > 10% at 12 months. RESULTS: WES identified at least one disease-related variant in 45 patients (54%). LVRR occurred in 28 patients (34%), most often in carriers of isolated titin truncated variants, followed by individuals with a negative, or inconclusive WES and carriers of other disease-related variants (56% vs. 42% vs. 19%, P=0.041). CONCLUSION: A substantial proportion of RODCM cases have a monogenic or oligogenic genetic background. Carriers of non-titin disease-related variants are less likely to reach LVRR at 12- months than other individuals. Genetic testing could contribute to better prognosis prediction and individualized treatment of RODCM.
Subject(s)
Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/physiopathology , Exome Sequencing , Genetic Predisposition to Disease , Ventricular Remodeling/genetics , Adult , Cardiomyopathy, Dilated/epidemiology , Czech Republic/epidemiology , Female , Genetic Variation , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies , Retrospective StudiesABSTRACT
Cryptic species within the section Fumigati, that is Aspergillus fumigatus-like species, are increasingly reported in the literature as causative agents of invasive aspergillosis (IA) in both humans and animals. Their detection and proper identification are important, but even more important is to determine the susceptibility profile (minimum inhibitory concentrations, MICs) of the isolate to antifungals using appropriate methods. Cryptic species often demonstrate elevated MICs to drugs recommended for IA therapy such as voriconazole or amphotericin B. Presented is a case of pulmonary aspergillosis in a 63-year-old male heart transplant recipient. Aspergillus lentulus with reduced susceptibility to voriconazole and amphotericin B was identified as the causative agent of the infection using culture and DNA sequencing. Susceptibility to antifungals was confirmed by the standard EUCAST-AFST methods. Based on MIC values obtained in vitro, therapy was switched from voriconazole to posaconazole with excellent clinical effects. To the best of our knowledge, this is the first reported case of A. lentulus infection treated with posaconazole and, moreover, a successful one.
Subject(s)
Aspergillosis , Aspergillus , Transplant Recipients , Antifungal Agents/pharmacology , Aspergillosis/microbiology , Aspergillus/classification , Aspergillus/drug effects , Heart Transplantation , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Triazoles/pharmacology , Triazoles/therapeutic use , Voriconazole/pharmacology , Voriconazole/therapeutic useABSTRACT
Danon disease (DD) is an X-linked disorder caused by mutations in the lysosomal-associated membrane protein 2 (LAMP2) gene (Xq24). DD is characterized by cognitive deficit, myopathy, and cardiomyopathy in male patients. The phenotype is variable and mitigated in females. The timely identification of de-novo LAMP2 mutated family members, many of whom are heterozygous females, remains critical for their treatment and family counseling. DD laboratory testing builds on minimally invasive quantification of the LAMP2 protein in white blood cells and characterization of the specific mutation. This integrative approach is particularly helpful when assessing suspect female heterozygotes. LAMP2 exon-copy number variations (eCNVs) were so far reported only in X-hemizygous male DD probands. In heterozygous female DD probands, the wild-type allele may hamper the identification of an eCNV even if it results in the complete abolition of LAMP2 transcription and/or translation. To document the likely underappreciated rate of occurrence and point out numerous potential pitfalls of detection of the LAMP2 eCNVs, we present the first two DD heterozygote female probands who harbor novel multi-exon LAMP2 deletions. Critical for counseling and recurrence prediction, we also highlight the need to search for somatic-germinal mosaicism in DD families.
Subject(s)
DNA Copy Number Variations/genetics , Exons/genetics , Glycogen Storage Disease Type IIb/genetics , Lysosomal-Associated Membrane Protein 2/genetics , Adolescent , Adult , Base Sequence , Child , Family , Female , Heterozygote , Humans , Male , Pedigree , Young AdultABSTRACT
Protein-losing enteropathy (PLE) due to leakage of lymph into the gut sometimes occurs in young patients after Fontan palliation but is very rarely reported with other aetiologies of chronic heart failure (HF). PLE leads to severe hypoalbuminemia and immunodeficiency and is associated with poor prognosis. The mechanisms and the predispositions to PLE are poorly understood. Here, we report an adult patient with advanced HF due to non-ischaemic non-dilated hypocontractile cardiomyopathy who developed severe PLE, probably owing to increased ventricular stiffness and constraint by atypically placed epicardial electrode encircling both ventricles. Importantly, both PLE and immunodeficiency completely resolved after heart transplantation.
Subject(s)
Cardiomyopathies/etiology , Heart Transplantation , Heart Ventricles/diagnostic imaging , Protein-Losing Enteropathies/complications , Cardiomyopathies/diagnosis , Cardiomyopathies/surgery , Disease Progression , Heart Ventricles/physiopathology , Humans , Male , Middle Aged , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: B-type natriuretic peptide (BNP) is a strong predictor of prognosis in chronic heart failure. We aimed to evaluate the clinical correlates and interpretation of BNP monitoring in LVAD out-patient recipients. METHODS: We performed a prospective study in 136 individuals after HeartMate II LVAD implantation. During follow-up they were divided into group A (severe adverse events requiring hospitalisation), group B (mild to moderate adverse events) and group C (an uneventful course). BNP was measured pre-implant, at the first out-patient visit, and then every 2 months. We identified the lowest level, and the level at the clinical event and/or the highest value in patients without clinical events (BNP peak). RESULTS: During a median follow-up of 298 days, 8 patients (6%) died, 21 patients (15%) experienced a severe adverse event (group A) and 38 patients (28%) had other adverse event (group B). Both the absolute value of BNP peak and its percentage values relative to pre-implant, first visit and minimum BNP had similar areas under the curve (AUC) to identify individuals with adverse events (group A and B) from group C. The performance of BNP peak rose from detection of infection to diagnosis of heart failure and culminated in individuals with pump thrombosis (AUC 0.68 vs. 0.75 vs. 0.93). CONCLUSIONS: Serial measurement of BNP in outpatients with LVAD correlates with the occurrence of adverse events. Assessment of absolute values of BNP peak seems to have a similar accuracy to analysis of intra-individual variation of BNP and it is more practical.
Subject(s)
Heart Failure/therapy , Heart-Assist Devices , Natriuretic Peptide, Brain/metabolism , Adult , Aged , Ambulatory Care/methods , Area Under Curve , Biomarkers/metabolism , Female , Heart Failure/blood , Humans , Male , Middle Aged , Monitoring, Ambulatory/methods , Postoperative Complications/blood , Postoperative Complications/diagnosis , Prospective Studies , Prosthesis-Related Infections/blood , Prosthesis-Related Infections/diagnosis , Ventricular Dysfunction, Left/blood , Ventricular Dysfunction, Left/therapy , Young AdultABSTRACT
We report a case of phaeohyphomycosis caused by Alternaria infectoria in a 61-year-old heart transplant recipient with multiple skin lesions and pulmonary infiltrates. The infection spread via the haematogenous route from the primary cutaneous lesions into the lungs. The diagnosis was based on the histopathological examination, direct microscopy, skin lesion cultures and detection of Alternaria DNA in the bronchoalveolar lavage fluid using molecular methods. The treatment consisted of a combination of surgical excision and systemic antifungal therapy. Voriconazole was the first agent used but had a weak effect. Posaconazole was subsequently used to achieve a successful response. The isolate was identified as A. infectoria by sequencing of the rDNA ITS region and the partial ß-tubulin gene.