Some studies have shown that metrics of load independent contractility (such as left ventricular stiffness) reveal diminished systolic function in HFpEF patients compared to healthy controls, and are corroborated by tissue Doppler findings that reveal changes in longitudinal contraction and motion abnormalities. While these systolic impairments may be minimal at rest, they become more exaggerated with increased demand, as seen in exercise. Pulmonary hypertension and right ventricular dysfunction
Most HFpEF patients exhibit pulmonary hypertension which is significantly associated with increased morbidity and mortality. Left atrial and pulmonary venous pressure increases in HFpEF due to diastolic insufficiency thus increasing pulmonary artery pressure. In patients with advanced HFpEF changes in the pulmonary vasculature may develop, leading to pre-capillary pulmonary hypertension. Right ventricular dysfunction is also common in HFpEF patients, occurring in 20-35% of patients. This right ventricular dysfunction is more common in patients with more advanced HFpEF as well as those with pulmonary hypertension and lower ejection fractions. Heart rate
Cardiac output is dependent on stroke volume and heart rate. A significant portion (55-77%) of HFpEF patients are unable to increase heart rate to compensate for increased output demand (as in the setting of exercise); this is termed chronotropic incompetence. Combined with the characteristic deficit in stroke volume observed in HFpEF patients, many individuals display poor exercise tolerance. Dyssynchrony
Non-simultaneous contraction of the left and right ventricle, dyssychrony, is present in up to 58% of HFpEF patients. However, dyssynchrony is also common in HFrEF and its role in HFpEF in particular remains obscure.
Levoketoconazole, sold under the brand name Recorlev, is a steroidogenesis inhibitor that is used for the treatment of Cushings syndrome. Levoketoconazole was approved for medical use in the United States in December 2021.Levoketoconazole is the levorotatory or (2S,4R) enantiomer of ketoconazole, and it is an inhibitor of the enzymes CYP11B1 (11β-hydroxylase), CYP17A1 (17α-hydroxylase/17,20-lyase), and CYP21A2 (21-hydroxylase). It inhibits glucocorticoid biosynthesis and hence circulating levels of glucocorticoids, thereby treating Cushings syndrome. In addition to its increased potency, the drug is 12-fold less potent than racemic ketoconazole in inhibiting CYP7A1 (cholesterol 7α-hydroxylase), theoretically resulting in further reduced interference with bile acid production and metabolite elimination and therefore less risk of hepatotoxicity. Levoketoconazole has also been found to inhibit CYP11A1 (cholesterol side-chain cleavage enzyme) and CYP51A1 (lanosterol-14α-demethylase), similarly but more potently relative to ketoconazole. References
External links
"Levoketoconazole". Drug Information Portal. U.S. National Library of Medicine. Clinical trial number NCT03277690 for "A Study to Assess the Safety and Efficacy of Levoketoconazole in the Treatment of Endogenous Cushings Syndrome" at ClinicalTrials.gov
Clinical trial number NCT01838551 for "Treatment for Endogenous Cushings Syndrome (SONICS)" at ClinicalTrials.gov