Background— Most studies of amyloidotic cardiomyopathy consider as a single entity the 3 main systemic cardiac amyloidoses: acquired monoclonal immunoglobulin light-chain (AL); hereditary, mutated transthyretin-related (ATTRm); and wild-type transthyretin-related (ATTRwt). In this study, we compared the diagnostic/clinical profiles of these 3 types of systemic cardiac amyloidosis. Methods and Results— We conducted a longitudinal study of 233 patients with clear-cut diagnosis by type of cardiac amyloidosis (AL, n=157; ATTRm, n=61; ATTRwt, n=15) at 2 large Italian centers providing coordinated amyloidosis diagnosis/management facilities since 1990. Average age at diagnosis was higher in AL than in ATTRm patients; all ATTRwt patients except 1 were elderly men. At diagnosis, mean left ventricular wall thickness was higher in ATTRwt than in ATTRm and AL. Left ventricular ejection fraction was moderately depressed in ATTRwt but not in AL or ATTRm. ATTRm patients less often displayed low QRS voltage (25% versus 60% in AL; P <0.0001) or low voltage-to-mass ratio (1.1±0.5 versus 0.9±0.5; P <0.0001). AL patients appeared to have greater hemodynamic impairment. On multivariate analysis, ATTRm was a strongly favorable predictor of survival, and ATTRwt predicted freedom from major cardiac events. Conclusions— AL, ATTRm, and ATTRwt should be considered 3 different cardiac diseases, probably characterized by different pathophysiological substrates and courses. Awareness of the diversity underlying the cardiac amyloidosis label is important on several levels, ranging from disease classification to diagnosis and clinical management.

Hereditary transthyretin (TTR)-related amyloidosis (ATTR) is mainly considered a neurologic disease. We assessed the phenotypic and genotypic spectra of ATTR in a Caucasian area and evaluated the prevalence, genetic background, and disease profile of cases with an exclusively cardiac phenotype, highlighting possible hints for the differential diagnosis with hypertrophic cardiomyopathy (HCM) and senile systemic amyloidosis (SSA). In this Italian multicentre study, 186 patients with ATTR were characterized at presentation. Thirty patients with SSA and 30 age–gender-matched HCM patients were used for comparison. Phenotype was classified as exclusively cardiac (n = 31, 17%), exclusively neurologic (n = 46, 25%), and mixed cardiac/neurologic (n = 109, 58%). Among the eight different mutations responsible for an exclusively cardiac phenotype, Ile68Leu was the most frequent. Five patients with an exclusively cardiac phenotype developed mild abnormalities at neurological examination, but no symptoms during a 36-month follow-up (range: 14–50). Exclusively cardiac phenotype was characterized by male gender, age >65 years, heart failure symptoms, symmetric left ventricular (LV) ‘hypertrophy’, and moderately depressed LV ejection fraction. This profile was similar to SSA, but relatively distinct from HCM. Compared with patients with a mixed phenotype, patients with an exclusively cardiac phenotype showed a more pronounced cardiac involvement on both echocardiogram and electrocardiogram (ECG). A clinically relevant subset of Caucasian ATTR patients present with an exclusively cardiac phenotype, mimicking HCM or SSA. Echocardiographic and ECG findings are useful to differentiate ATTR from HCM but not from SSA. The role of liver transplantation in these patients should be reconsidered.

Duchenne muscular dystrophy (DMD) is an X-linked inherited neuromuscular disorder due to mutations in the dystrophin gene. It is characterized by progressive muscle weakness and wasting due to the absence of dystrophin protein that causes degeneration of skeletal and cardiac muscle. The molecular diagnostic of DMD involves a deletions/duplications analysis performed by quantitative technique such as microarray-based comparative genomic hybridization (array-CGH), Multiple Ligation Probe Assay MLPA. Since traditional methods for detection of point mutations and other sequence variants require high cost and are time consuming, especially for a large gene like dystrophin, the use of next-generation sequencing (NGS) has become a useful tool available for clinical diagnosis. The dystrophin gene is large and finely regulated in terms of tissue expression, and RNA processing and editing includes a variety of fine tuned processes. At present, there are no effective treatments and the steroids are the only fully approved drugs used in DMD therapy able to slow disease progression. In the last years, an increasing variety of strategies have been studied as a possible therapeutic approach aimed to restore dystrophin production and to preserve muscle mass, ameliorating the DMD phenotype. RNA is the most studied target for the development of clinical strategies and Antisense Oligonucleotides (AONs) are the most used molecules for RNA modulation. The identification of delivery system to enhance the efficacy and to reduce the toxicity of AON is the main purpose in this area and nanomaterials are a very promising model as DNA/RNA molecules vectors. Dystrophinopathies therefore represent a pivotal field of investigation, which has opened novel avenues in molecular biology, medical genetics and novel therapeutic options.

Using array comparative genome hybridisation (CGH) 41 de novo reciprocal translocations and 18 de novo complex chromosome rearrangements (CCRs) were screened. All cases had been interpreted as “balanced” by conventional cytogenetics. In all, 27 cases of reciprocal translocations were detected in patients with an abnormal phenotype, and after array CGH analysis, 11 were found to be unbalanced. Thus 40% (11 of 27) of patients with a “chromosomal phenotype” and an apparently balanced translocation were in fact unbalanced, and 18% (5 of 27) of the reciprocal translocations were instead complex rearrangements with >3 breakpoints. Fourteen fetuses with de novo, apparently balanced translocations, all but two with normal ultrasound findings, were also analysed and all were found to be normal using array CGH. Thirteen CCRs were detected in patients with abnormal phenotypes, two in women who had experienced repeated spontaneous abortions and three in fetuses. Sixteen patients were found to have unbalanced mutations, with up to 4 deletions. These results suggest that genome-wide array CGH may be advisable in all carriers of “balanced” CCRs. The parental origin of the deletions was investigated in 5 reciprocal translocations and 11 CCRs; all were found to be paternal. Using customised platforms in seven cases of CCRs, the deletion breakpoints were narrowed down to regions of a few hundred base pairs in length. No susceptibility motifs were associated with the imbalances. These results show that the phenotypic abnormalities of apparently balanced de novo CCRs are mainly due to cryptic deletions and that spermatogenesis is more prone to generate multiple chaotic chromosome imbalances and reciprocal translocations than oogenesis.