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Sickle cell disease (SCD) is characterized by repeated episodes of hemolysis and vaso-occlusion. Hemolysis is a risk factor for the development of pulmonary hypertension (PH), and currently SCD-related PH is classified as World Health Organization group 5 PH. Patients with SCD-related PH have unique hemodynamics, comorbidities, and phenotypes that may contribute to the development of PH. SCD-related PH is defined as a mean pulmonary artery pressure >20 mm Hg, a pulmonary artery occlusion pressure ≤15 mm Hg and relatively low pulmonary vascular resistance (PVR) (>160 dynes·sec/cm5 rather than the typical definition of ≥240 dynes·sec/cm5), an important distinction because of a baseline high-cardiac output state in the setting of chronic anemia and low vascular resistance. Diastolic dysfunction is common, and right heart catheterization is warranted to determine if combined precapillary and postcapillary PH is present. Thromboembolism is common among patients with SCD, and screening for chronic thromboembolic pulmonary hypertension is essential. There are few studies evaluating advanced therapies in this population. The mainstay of treatment includes targeting correction of their primary hemoglobinopathy as well as aggressive management of underlying comorbid conditions. SCD-related PH is common among patients with SCD and is associated with increased mortality. A high index of suspicion is warranted during evaluation to identify all potential factors that may be contributing to disease. [ABSTRACT FROM AUTHOR]

The efficiency of blood flowing from the heart depends on its electrical properties. Myocardial electrical activity is associated with generating cardiac action potentials in isolated myocardial cells and their coordinated propagation, which are mediated by gap junctions. Atrial fibrillation (AF) is a common cardiac arrhythmia which causes an aggressive disturbance in cardiac electromechanical function. Moreover, AF increases the risk of stroke and mortality and is a major cause of death. The mechanisms underlying AF involve electrophysiological changes in ion channel expression and function. β-blockers may be useful in patients with chronic AF or in preventing postoperative AF in subjects undergoing coronary artery bypass grafting (CABG) or other types of surgery. The reduction in heart rate induced by β1-adrenergic receptor antagonists may be associated with the beneficial effect of this drug class. Second generation beta-blockers may be considered superior to the first generation due to their selectivity to the β1 receptor as well as avoiding pulmonary or metabolic adverse effects. Third generation beta-blockers may be considered a great option for their vasodilation and antioxidant properties. There is also a new β-blocker, named landilol that also results on reduced risk of post operative AF without adverse effects and its use has been increasing in clinical trials., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)