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Background PTPN11 is ubiquitously expressed and has a variety of phenotypes even in a single heart. We examined LEOPARD syndrome (LS) in a patient with PTPN11 variants through pathological, electrophysiological, and anatomical studies. Case summary A 49-year-old man with no previous medical history was brought to our emergency department because of syncope. An electrocardiogram (ECG) revealed alternating bundle branch block, and echocardiography revealed hypertrophic cardiomyopathy-like morphology with systolic anterior motion of the posterior mitral valve. Atrioventricular block, left ventricular outflow tract (LVOT) obstruction, and ventricular tachycardia were considered the differential diagnoses; however, the treatment plan was difficult to determine. An electrophysiological study revealed the cause of the ECG abnormality to be accelerated idioventricular rhythm, and the programmed ventricular stimulation was negative. Genetic testing revealed LS with PTPN11 variant, which was speculated to be the cause of these various unique cardiac features. The cause of syncope was considered to be exacerbation of LVOT obstruction due to dehydration, and the patient was treated with oral beta-blockers. Implantable loop recorder observation for 1 year revealed no arrhythmia causing syncope, and an implantable cardioverter-defibrillator and pacemaker were deemed unnecessary for primary prevention of syncope. During 2.5 years of follow-up, the LVOT peak velocity fluctuated between 2.5 and 3.5 m/s, but the patient remained stable with no recurrent syncope. Conclusion We confirmed that LS is distinct from other cardiomyopathies using characterization, physiological, electrophysiological, and pathological examinations. Evidence supporting a specific treatment strategy for LS is limited, and understanding the pathogenesis may help establish effective treatment strategies. [ABSTRACT FROM AUTHOR]

Recently, there have been increasing opportunities to treat patients with peripheral arterial disease. Of those patients, both pathological conditions, such as acute limb ischemia (ALI) and chronic critical limb ischemia (CLI), are closely associated with high risks of major amputation, disability and death. We encountered a very rare case of CLI subsequent to ALI. An 83-year-old male showed the sudden onset of ALI, probably due to thromboembolism from an abdominal aortic aneurysm during an operation for gastric cancer. The patient was referred to another hospital for Fogarty thrombectomy. About 1 month after ALI onset, necrosis of the left first toe gradually progressed. On angiography of the left lower limb, we noted occlusions of both anterior and posterior tibial arteries. Then, we successfully conducted balloon angioplasty for the below-the-knee arteries. Thereby, favorable blood flow was achieved, which led to successful wound healing without amputations. [ABSTRACT FROM AUTHOR]

Currently, there are more opportunities to treat patients complicated with critical limb ischemia (CLI), which is a very dismal medical condition associated with a high risk of major amputation, disability and death. Because CLI is usually caused by multi-level occlusive atherosclerotic disease, the condition of CLI induced by aorto-iliac occlusive disease (AIOD) alone is thought to be a rare pathological entity. We encountered a patient with severe CLI caused by solitary AIOD. Three vascular access routes were established and stiff guidewires retrogradely passed the occluded arteries on both sides. We deployed two self-expandable bare metal stents and complete revascularization led to wound healing. Recent improvements of catheter devices and procedural techniques related to endovascular treatment (EVT) have enabled us to safely recanalize complex vascular lesions of the lower extremities. Therefore, an EVT strategy is one of the favorable treatment options for CLI patients who are contraindicated for surgical treatments. [ABSTRACT FROM AUTHOR]

Objectives: The present study examined the possibility that intracellular ATP levels dictate whether hypoxic cardiac myocytes die by apoptosis or necrosis. Background: Although apoptosis and necrosis may appear to be distinct forms of cell death, recent studies suggest that the two may represent different outcomes of a common pathway. In ischemic myocardium, apoptosis appears early, while energy stores are presumably still available, followed only later by necrosis. Methods: Neonatal rat cardiac myocytes were exposed to continuous hypoxia, during which the intracellular ATP concentration was modulated by varying the glucose content in the medium. The form of cell death was determined at the end of the hypoxic exposure. Results: Under total glucose deprivation, ATP dropped precipitously and cell death occurred exclusively by necrosis as determined by nuclear staining with ethidium homodimer-1 and smearing on DNA agarose gels. However, with increasing glucose concentrations (10, 20, 50, 100 mg/dl) cellular ATP increased correspondingly, and apoptosis progressively replaced necrosis until it became the sole form of cell death, as determined by nuclear morphology, DNA fragmentation on agarose gels, and caspase-3 activation. The data showed a significantly positive correlation between myocyte ATP content and the percentage of apoptotic cells. Hypoxia resulted in lactate production and cellular acidification which stimulates apoptosis. However, acidification-induced apoptosis was also increased in an ATP-dependent fashion. Loss of mitochondrial membrane potential and cytochrome c release from the mitochondria was observed in both the apoptotic and necrotic cells. Furthermore, translocation of Bax from cytosol into mitochondria preceded these events associated with mitochondrial permeability transition. Increased lactate production and a lack of effect by the mitochondrial inhibitor oligomycin indicated that ATP was generated exclusively through glycolysis. Conclusions: We demonstrate that ATP, generated through glycolysis, is a critical determinant of the form of cell death in hypoxic myocytes, independently of cellular acidification. Our data suggest that necrosis and apoptosis represent different outcomes of the same pathway. In the absence of ATP, necrosis prevails. However, the presence of ATP favors and promotes apoptosis. [Copyright &y& Elsevier]