Pulmonary Hypertension in Circulation and the Circulation Subspecialty Journals

Abstract

The following articles are being highlighted as part of Circulation's Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in Circulation and the Circulation subspecialty journals. The studies included in this article represent the articles related to pulmonary hypertension that were published in Circulation and the Circulation subspecialty journals in . (Circulation. 2012125:e645-e652.) Nitrite Potently Inhibits Hypoxic and Inflammatory Pulmonary Arterial Hypertension and Smooth Muscle Proliferation via Xanthine Oxidoreductase-Dependent Nitric Oxide GenerationSummary: Pulmonary arterial hypertension is a disease of the small pulmonary arteries that is characterized by progressive pulmonary vascular remodeling, vasoconstriction, and thrombosis. These changes lead to increased pulmonary vascular pressures and cause right heart failure, which leads to death. In general, therapies have not been effective in reversing the pathophysiological changes associated with pulmonary arterial hypertension. Our investigations define inhaled nebulized sodium nitrite as a potential therapy for pulmonary arterial hypertension. These data demonstrate that sodium nitrite can prevent or reverse pulmonary arterial hypertension in multiple experimental animal models of this disease process. Furthermore, these data show that nitrite is enzymatically converted to vasoactive nitric oxide in lung tissue and pulmonary artery smooth muscle cells via xanthine oxidoreductase. These findings help to define a therapy that may be useful in the treatment of patients with this insidious disease that to this point has lacked effective pharmacological therapies.Conclusion: These studies reveal a potent effect of inhaled nitrite that limits pathological pulmonary arterial hypertrophy and cellular proliferation in the setting of experimental pulmonary arterial hypertension. 1 Ventricular Geometry, Strain, and Rotational Mechanics in Pulmonary HypertensionSummary: As a result of ventricular interdependence, analysis of concomitant intrinsic left ventricular (LV) diseases (ie, myocardial fibrosis) in patients with significant pulmonary hypertension (PH) is challenging. The farther a region is from the right ventricle (eg, the lateral wall), the less the impact will be that the PH has on LV strain. Furthermore, parameters based on circumferential fibers appear to propagate farther from the right ventricle than longitudinal parameters, likely reflecting continuity of the circumferential fibers from the septum to the lateral wall. Accordingly, a finding of abnormal LV lateral wall longitudinal strain in patients with PH might identify true LV dysfunction that is independent of PH. We further demonstrated that LV torsion correlated negatively with estimated pulmonary artery systolic pressure and with septal flattening. Abnormally reduced LV torsion in PH could represent an advanced stage of PH and geometric alteration. Interestingly, although torsion was reduced, untwisting velocity was s...