Right ventricular (RV) dysfunction is the most important determinant of survival in patients with pulmonary hypertension (PH). The manifestations of RV dysfunction not only include changes in global RV systolic function but also abnormalities in the pattern of contraction and synchrony. The effects of PH on the right ventricle have been mainly studied in patients with pulmonary arterial hypertension (PAH).However, with the demographic shift towards an aging population, heart failure with preserved ejection fraction (HFpEF) has become an important etiology of PH in recent years. There are significant differences in RV mechanics, function and adaptation between patients with PAH and HFpEF (with or without PH), which are related to different patterns of remodeling and dysfunction. Due to the unique features of the RV chamber, its connection with the main pulmonary artery and the pulmonary circulation, an understanding of the mechanics of RV function and its clinical significance is mandatory for both entities. In this review, we describe the mechanics of the pressure overloaded right ventricle. We review the different mechanical components of RV dysfunction and ventricular dyssynchrony, followed by insights via analysis of pressurevolume loop, energetics and novel blood flow patterns, such as vortex imaging. We conduct an in-depth comparison of prevalence and characteristics of RV dysfunction in HFpEF and PAH, and summarize key outcome studies. Finally, we provide a perspective on needed and expected future work in the field of RV mechanics.
Introduction: Studies on the durability of an intensive, structured education protocol on best insulin injection practice are missing for people with type 2 diabetes mellitus (T2DM). The aim of this study was to assess the durability of an intensive, structured education-based rehabilitation protocol on best insulin injection practice in well-trained subjects from our previous intensive, multimedia intervention study registered as the ISTERP-1 study. A total of 158 subjects with T2DM from the well-trained group of the 6-month-long ISTERP-1 study, all of whom had successfully attained lower glucose levels compared to baseline levels with lower daily insulin doses and with less frequent and severe hypoglycemic episodes, participated in the present investigation involving an additional 6-month follow-up period, called the ISTERP-2 study. Methods: Participants were randomized into an intervention group and a control group, depending on whether they were provided or not provided with further education refresher courses for 6 months. At the end of the 6 months, the two groups were compared in terms of injection habits, daily insulin dose requirement, number of severe or symptomatic hypoglycemic events, and glycated hemoglobin (HbA1c) levels.
The second hit hypothesis in pulmonary hypertension refers to the development of pulmonary vascular disease in individuals at risk, after an additional exposure or “hit” to factors with potential injury to the pulmonary circulation, such as drugs or toxins. We here present a case of severe pulmonary hypertension diagnosed during the third trimester of pregnancy, in a patient with familial history of pulmonary hypertension, found to have a heterozygous mutation in the BMPR2 gene, who also had chronic exposure to prescription amphetamines. We hypothesize that exposure to prescription amphetamines could act as a second hit of pulmonary vascular injury in individuals at risk of pulmonary vascular disease.
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