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The diagnosis of neuromuscular disorders requires a thorough history including family history and examination, with the next steps broadened now beyond electromyography and neuropathology to include genetic testing. The challenge in diagnosis can often be putting all the information together. With advances in genetic testing, some diagnoses that adult patients may have received as children deserve a second look and may result in diagnoses better defined or alternative diagnoses made. Clearly defining or redefining a diagnosis can result in understanding of potential other systems involved, prognosis, or potential treatments. This article presents several cases and approach to diagnosis as well as potential treatment and prognostic concerns, including seipinopathy, congenital myasthenic syndrome, central core myopathy, and myotonic dystrophy type 2., Competing Interests: None declared., (Thieme. All rights reserved.)

Genetic disorders that disrupt the structure and function of the cardiovascular system and the peripheral nervous system are common enough to be encountered in routine cardiovascular practice. Although often these patients are diagnosed in childhood and come to the cardiologist fully characterized, some patients with hereditary neuromuscular disease may not manifest until adulthood and will present initially to the adult cardiologist for an evaluation of an abnormal ECG, unexplained syncope, LV hypertrophy, and or a dilated cardiomyopathy of unknown cause. Cardiologists are often ill-equipped to manage these patients due to lack of training and exposure as well as the complete absence of practice guidelines to aid in the diagnosis and management of these disorders. Here, we review three key neuromuscular diseases that affect the cardiovascular system in adults (myotonic dystrophy type 1, Friedreich ataxia, and Emery-Dreifuss muscular dystrophy), with an emphasis on their clinical presentation, genetic and molecular pathogenesis, and recent important research on medical and interventional treatments. We also advocate the development of interdisciplinary cardio-neuromuscular clinics to optimize the care for these patients., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Respiratory muscle weakness causes alveolar hypoventilation and reduced lung compliance in neuromuscular disorders. Lung inflation is important to prevent secondary pulmonary complications however respiratory and laryngeal dysfunction often hamper lung inflation. There is a need for a convenient and low-cost device that enables effective lung inflation. We tested a lung inflation training method using a positive end-expiratory pressure (PEEP) valve., Methods: Vital capacity (VC), maximum insufflation capacity (MIC) and peak cough flow (PCF) as well as PEEP lung inflation capacity (PIC) were assessed in 93 neuromuscular patients. Consecutive PIC training was done for 4 months in six tracheostomized Duchenne muscular dystrophy (DMD) patients and PIC was assessed before and after training., Results: PIC training was practicable in all participants and no serious adverse events were detected. PIC was significantly higher than VC or MIC in all disorders, although MIC was higher than VC in DMD only. Patients with dysphagia showed lower MIC and PCF compared with non dysphagic patients. PIC was as low as 345±77 mL in tracheostomized DMD patients; however consecutive training increased it up to 619±205 mL., Conclusion: The PEEP valve enabled effective lung inflation regardless of laryngeal function. Consecutive training can improve lung condition even in advanced cases. Early introduction of PIC training could be effective at preventing respiratory complications in patients with neuromuscular disorders.

Objective: To clarify the relationship between symptoms, clinical signs and physiological abnormalities that were motivating the initiation of home mechanical ventilation in patients suffering from neuromuscular diseases., Methods: From The Swedish Home Mechanical Ventilation Register we identified 352 patients with neuromuscular diseases and we looked at circumstances (acute vs elective) and clinical motives for starting ventilatory support., Results: Home mechanical ventilation was commenced electively in 268 patients (76%) and among these daytime sleepiness was the most common motive, being reported in 56% of the patients. In the 24 children with spinal muscular atrophy, however, 96% started ventilation electively and cough insufficiency was the most common motive. The patients were moderately hypercapnic (PaCO(2): 7.0 kPa, SD 1.3). None of the clinical motives were related to the PaCO(2) level. Average PaO(2) was above 8 kPa in all groups, but lowest in the patients with post-polio and dystrophia myotonica. Mean vital capacity was close to 40% of predicted, but significantly lower in the Duchenne patients (26% of predicted)., Conclusion: Daytime sleepiness was the most common clinical symptom motivating home mechanical ventilation in this group of patients with chronic hypercapnic respiratory insufficiency secondary to neuro/myopathies. Respiratory function testing is therefore suggested to be included in the diagnostic work up of daytime sleepiness in these patients.

Neuromuscular disorders represent a large group of highly varied and interesting clinical disorders, many of which have major general medical manifestations. These disorders can be diagnosed largely based on the patient's history and physical examination with a little help from modern technology. Despite the outdated belief that neurologic conditions are diagnosed but rarely treatable, all cases discussed herein represent disorders for which there are extensive options and opportunities for meaningful management. These 16 brief case overviews challenge and refresh diagnostic skills and provide the framework for selected comments regarding management options.

The recent development of recombinant human growth hormone (GH) and insulin-like growth factor 1 (IGF-1) has provided the opportunity to study the effects of these growth factors in humans. The majority of studies have been performed in healthy young and older adults. Both GH and IGF-1 have shown very positive effects on muscle protein anabolism. Relatively few side effects have developed. Initial studies have shown a beneficial effect of GH in reversing the catabolic actions of oral prednisone, and GH treatment has led to an increase in muscle mass and protein synthesis in pilot studies of myotonic dystrophy. Combination therapy in normal subjects using both GH and IGF-1 has shown encouraging results. There is a greater enhancement of protein anabolism during combined treatment than there is with either agent alone, and concomitant therapy with GH diminished the side effects of IGF-1. It is now feasible to consider therapeutic trials in patients. Future studies of GH and IGF-1 treatment in patients with primary muscle disease and in patients receiving long-term corticosteroid therapy are needed.