Strain analysis reveals subtle systolic dysfunction in confirmed and suspected myocarditis with normal LVEF. A cardiac magnetic resonance study.

AIMS: Lake Louise Criteria (LLC) are time-dependent and some acute myocarditis (AM) with preserved left ventricular ejection fraction (LVEF) could be missed, due to the limited accessibility of Cardiac Magnetic Resonance (CMR). We aimed to assess the potential value of cardiac strain measured by feature tracking (FT) imaging in this population. METHODS AND RESULTS: Eighty-three patients with clinically suspected AM and normal LVEF were divided into 39 "confirmed AM" (positive LLC) and 44 "suspected AM" (negative LLC). An age and gender-matched sample of 42 normal subjects underwent CMR. In all groups, FT-derived biventricular strains and STE- global longitudinal strain (GLS) were assessed, being regularly measurable. Strain values < 5th percentile of the control group were considered abnormal. "Suspected" and "confirmed" AM were similar, except for medium time of CMR evaluation (5.2 vs 1 months from presentation, respectively; p = 0.004). Compared to healthy controls, both "suspected" and "confirmed" AM showed significantly impaired strain values. LV-global circumferential strain (GCS), right ventricular GCS and LV-GLS were abnormal in 15.4% and 15.9%, 20.5% and 15.9%, 7.7% and 9.1% in "confirmed" and "suspected" AM, respectively. STE analysis confirmed the results on LV-GLS, however a weak correlation emerged between STE and CMR-FT LV-GLS (p = 0.08). CONCLUSIONS: Compared to STE, CMR-FT analysis provided a more comprehensive and complementary biventricular strain evaluation that resulted similar in "confirmed" and "suspected" AM with normal LVEF. Conversely, mostly biventricular GCS was significantly reduced in up to 20% of patients, compared to healthy controls.

Genetics of Dilated Cardiomyopathy: Clinical Implications.

PURPOSE OF REVIEW: This review aims to summarize the current knowledge on the genetic background of dilated cardiomyopathy (DCM), with particular attention to the genotype-phenotype correlations and the possible implications for clinical management. RECENT FINDINGS: Next generation sequencing (NGS) has led to the identification of an increasing number of genes and mutations responsible for DCM. This genetic variability is probably related to the extreme heterogeneity of disease manifestation. Important findings have associated mutations of Lamin A/C (LMNA) and Filamin C (FLNC) to poor prognosis and the propensity to cause an arrhythmic phenotype, respectively. However, a deeper understanding of the genotype-phenotype correlation is necessary, because it could have several implications for the clinical management of the patients. Furthermore, the correct interpretation of pathogenicity of mutations and the clinical impact of genetic testing in DCM patients still represent important fields to be implemented. A pathogenic gene mutation can be identified in almost 40% of DCM patients. The recent discoveries and future research in the field of genotype-phenotype correlation may lead to a more personalized management of the mutation carriers towards the application of precision medicine in DCM.

Ultrastructural and morphometric studies of Purkinje cells of brindled mouse after administration of cupric chloride.

The mitochondrial and dendritic changes in Purkinje cells, which developed transiently in cupric chloride treated brindled mice, were investigated chronologically with light and electron microscopy. Both changes occurred predominantly in the anterior lobe of the cerebellum. The maximal mitochondrial changes coincided with dendritic changes, suggesting that these alterations were causally related. In the focally swollen dendrites there were disruption of neurotubules, abnormal mitochondria with electron-lucent or electron-dense matrix and large lamellar bodies. Quantitative analysis of the dendritic spine revealed significant differences in the spine area and synaptic length between the brindled mice and normal littermates.

Rabbit sural nerve responses to chronic treatment with thalidomide and supidimide.

Chronic treatment of rabbits with thalidomide (3-(N-phthalimido) glutarimide) produced progressive decrements in sural nerve conduction velocity (NCV) that were unassociated with qualitative or quantitative morphological changes of nervous tissue. Three groups of eight rabbits received 100 mg/kg/day thalidomide (group I), 200 mg/kg/day supidimide (a related drug) (group II), or a carboxymethylcellulose vehicle (group III) 5 days/week for 40 weeks. At 6 months of treatment, a noninvasive determination of the mean maximum sural NCV for group I was significantly reduced relative to the conduction velocities of groups II and III. Direct measurement of conduction velocity when treatment was terminated confirmed these findings and demonstrated similar conduction deficits in proximal and distal portions of the sural nerve in group I animals. At 6 months, rabbits in group II showed a significant reduction in mean conduction velocity, and, at the termination of treatment, they displayed mean values similar to that of group III and significantly greater than that of group I. Morphological findings were unremarkable in 20 regions of the central nervous system (CNS) and the peripheral nervous system (PNS) known to display changes early in toxic neuropathies. Morphometric estimation of unmyelinated and myelinated fibers in the sural nerve at the heel revealed no between-group differences in axon diameter, fiber diameter, g-ratio (the ratio of inside/outside diameters), or internodal length. In conclusion, chronic treatment with thalidomide produces selected decrements in sural nerve function that have an unknown relationship to the poorly reversible sensory neuropathy reported in humans receiving this drug.

Some quantitative results on Golgi impregnated axons in rat visual cortex using a computer assisted video digitizer.

Axonal fiber distributions of pyramidal cells in the visual cortex of the albino rat have been investigated using the rapid Golgi method and modern data collecting techniques. Three dimensional coordinate information was extracted from Golgi-impregnated axonal networks using a computer-assisted video digitizer. Computer programs used this data to generate various statistical distributions. In particular, angular distributions of the initial collateral segments and their endpoints were examined and found to reveal anisotropies. Inspection of the spatial distributions of the endpoints indicated a clustering at two distinct levels with respect to the pyramidal cell from which they originate. Dynamic graphic displays of the three dimensional data have been obtained and presented in the form of computer tracings of various orthogonal projections.