Renal effects of SGLT2 inhibitors in cardiovascular patients with and without chronic kidney disease: focus on heart failure and renal outcomes.

The kidney has a prominent role in maintaining glucose homeostasis by using glucose as a metabolic substrate. This occurs by generating glucose through gluconeogenesis, and by reuptaking filtered glucose through the sodium-glucose cotransporters SGLT1 and SGLT2 located in the proximal tubule. In recent studies, the administration of sodium-glucose cotransporters inhibitors demonstrated that inhibition of renal glucose reabsorption significantly reduces adverse renal events and heart failure exacerbations, in type 2 diabetic patients with and without cardiovascular damage as well as in advanced chronic kidney disease and heart failure patients with reduced ejection fraction with and without diabetes. The benefit was consistent throughout the different investigated clinical conditions, ameliorating overall patient outcome. The efficacy of sodium glucose cotransporters inhibitors was prominently linked to the limitation of renal damage as highlighted by the significant reduction on global mortality achieved in the studies investigating diabetic and not diabetic populations with advanced chronic kidney disease. Both studies were halted at the interim analysis because of unquestionable evidence of treatment benefit. In current review, we examine the role of SGLT2 and SGLT1 in the regulation of renal glucose reabsorption in health and disease and the effect of SGLT2 inhibition on clinical outcomes of populations with different cardiovascular conditions investigated with large-scale outcome trials.

Superior Prognostic Value of Right Ventricular Free Wall Compared to Global Longitudinal Strain in Patients With Heart Failure.

BACKGROUND: Global right ventricular (RV) longitudinal strain (RVGLS) and free wall RV longitudinal strain (RVFWS) have both been advocated as sensitive tools to evaluate RV function and predict prognosis in patients with heart failure and reduced ejection fraction (HFrEF). However, because the interventricular septum is an integral part of the left ventricle (LV) also, RVGLS might be influenced by LV dysfunction. Thus, we compared the prognostic performance of either RV strain parameter in HFrEF patients, also taking into account the degree of LV systolic dysfunction. METHODS: In 288 prospectively enrolled outpatients with stable HFrEF, RVGLS and RVFWS were assessed by speckle-tracking and LV systolic function by global longitudinal strain and LV ejection fraction. Patients were followed up for 30.2 ± 23.0 months; the primary endpoint was all-cause death/heart failure-related hospitalization. Prognostic performance was assessed by C-statistic and net reclassification improvement. RESULTS: There were 95 events during follow-up. By univariable analysis, both RVGLS (hazard ratio × 1 SD, 1.60; 95% CI, 1.29-1.99; P < .0001) and RVFWS (hazard ratio × 1 SD, 1.82; 95% CI, 1.45-2.29; P < .0001) were associated with outcome, and both remained significant after correction for EMPHASIS risk score, New York Heart Association class, natriuretic peptides, and therapy. However, after further correction for LV systolic function parameters, only RVFWS remained significantly associated with outcome (P < .01). A basic prediction model was improved by adding RVFWS (net reclassification improvement 0.390; P < .05), but not RVGLS. CONCLUSIONS: Although both RVGLS and RVFWS have prognostic value, RVFWS better predicts outcome in HFrEF patients, mainly because it is less influenced by LV longitudinal dysfunction.

Improvements in signs and symptoms during hospitalization for acute heart failure follow different patterns and depend on the measurement scales used: an international, prospective registry to evaluate the evolution of measures of disease severity in acute heart failure (MEASURE-AHF).

BACKGROUND: The natural evolution of signs and symptoms during acute heart failure (AHF) is poorly characterized. METHODS AND RESULTS: We followed a prospective international cohort of 182 patients hospitalized with AHF. Patient-reported dyspnea and general well-being (GWB) were measured daily using 7-tier Likert (-3 to +3) and visual analog scales (VAS, 0-100). Physician assessments were also recorded daily. Mean age was 69 years and 68% had ejection fraction <40%. Likert measures of dyspnea initially improved rapidly (day 1, 0.22; day 2, 1.31; P <.001) with no significant improvement thereafter (day 7, 1.51; day 2 versus 7 P = .16). In contrast, VAS measure of dyspnea improved throughout hospitalization (day 1, 50.1; day 2, 64.7; day 7, 83.2; day 1 versus 2 P < .001, day 2 versus 7 P < .001). Symptoms of dyspnea and GWB tracked closely (correlation r = .813, P < .001). Physical signs resolved more completely than did symptoms (eg, from day 1 to discharge/day 7, absence of edema increased from 33% to 72% of patients, whereas significant improvements in dyspnea increased from 27% to 52% of patients; P < .001). CONCLUSIONS: Changes in patient-reported symptoms and physician-assessed signs followed different patterns during an AHF episode and are influenced by the measurement scales used. Multiple clinical measures should be considered in discharge decisions and evaluation of AHF therapies.

Left Atrial Reservoir Function and Outcome in Heart Failure With Reduced Ejection Fraction.

Background Left atrial (LA) volume is a marker of cardiac remodeling and prognosis in heart failure (HF) with reduced ejection fraction (EF), but LA function is rarely measured or characterized. We investigated determinants and prognostic impact of LA reservoir function in patients with HF with reduced EF. Methods and Results In 405 patients with stable HF with reduced EF (EF, ≤40%) in sinus rhythm, we assessed LA reservoir function by both LA total EF (by phasic volume changes) and peak atrial longitudinal strain (PALS; by speckle tracking echocardiography); LA functional index was also calculated. During follow-up (median, 30 months; Q1-Q3, 13-52), 139 patients (34%) reached the composite end point (all-cause death/HF hospitalization). Median PALS was 15.5% (interquartile range, 11.2-20.6). By univariable analysis, all LA function parameters significantly predicted outcome ( P <0.01 for all), with PALS showing the highest predictive accuracy (area under the curve, 0.75; sensitivity, 73%; specificity, 70%). Impaired PALS was associated with greater left ventricular and LA volumes, worse left ventricular EF, left ventricular global longitudinal strain, right ventricular systolic function, and more severe diastolic dysfunction. After multivariable adjustment (including LA volume and left ventricular global longitudinal strain), PALS, but not LA total EF or LA functional index, remained significantly associated with outcome (hazard ratio per 1-SD decrease, 1.38; 95% CI, 1.05-1.84; P=0.030). Adding PALS to a base model, including age, sex, LA volume, EF, E/E' ratio, and global longitudinal strain, provided incremental predictive value (continuous net reclassification improvement, 0.449; P=0.0009). Conclusions In HF with reduced EF, assessment of LA reservoir function by PALS allows powerful prognostication, independently of LA volume and left ventricular longitudinal contraction.