Mode of Death Prevention by Serelaxin

Neutrophil-Lymphocyte Ratio in Patients with Acute Heart Failure Predicts In-Hospital and Long-Term Mortality

The application of a simple blood test to predict prognosis in acute heart failure (AHF) patients is not well established. Neutrophil-lymphocyte ratio (NLR) is inexpensive and easy to obtain in hospitalized patients using a routine blood test. We evaluate the prognostic implications of NLR as an independent predictor of in-hospital and long-term mortality in AHF patients. Among 5625 patients enrolled in the Korean Acute Heart Failure registry, 5580 patients were classified into quartiles by their NLR level, and analyzed for in-hospital and post-discharge three-year mortality. Patients in the highest NLR quartile had the highest in-hospital and post-discharge three-year mortality. The same results were seen by dividing the aggravating factor into the infection or ischemia group and the non-infection or non-ischemia group. For patients aggravated from infection or ischemia, a cut-off NLR value was 7.0 that increase the risk of in-hospital and post-discharge three-year mortality. In subgroups of patients not aggravated from infection or ischemia, a cut-off NLR value was 5.0 that increase the risk of in-hospital and post discharge three-year mortality. Elevated NLR in AHF patients at the index hospitalization is an independent predictor for in-hospital and post-discharge three-year mortality. Taken together, NLR is a marker for risk assessment of AHF patients.

Effects of Widespread Inotrope Use in Acute Heart Failure Patients

Current guidelines recommend that inotropes should not be used in patients with normal systolic blood pressure (SBP). However, this is not supported with concrete evidence. We aimed to evaluate the effect of inotropes in acute heart failure (HF) patients from a nationwide HF registry. A total of 5625 patients from the Korean Acute Heart Failure (KorAHF) registry were analyzed. The primary outcomes were in-hospital adverse events and 1-month mortality. Among the total population, 1703 (31.1%) received inotropes during admission. Inotrope users had a higher event rate than non-users (in-hospital adverse events: 13.3% vs. 1.4%, p < 0.001; 1-month mortality: 5.5% vs. 2.5%, p < 0.001), while inotrope use was an independent predictor for clinical outcomes (in-hospital adverse events: OR_adjusted 5.459, 95% CI 3.622–8.227, p < 0.001; 1-month mortality: HR_adjusted 1.839, 95% CI 1.227–2.757, p = 0.003). Subgroup analysis showed that inotrope use was an independent predictor for detrimental outcomes only in patients with normal initial SBP (≥90 mmHg) (in-hospital adverse events: OR_adjusted 5.931, 95% CI 3.864–9.104, p < 0.001; 1-month mortality: HR_adjusted 3.584, 95% CI 1.280–10.037, p = 0.015), and a propensity score-matched population showed consistent results. Clinicians should be cautious with the usage of inotropes in acute heart failure patients, especially in those with a normal SBP.

Relaxin suppresses atrial fibrillation in aged rats by reversing fibrosis and upregulating Na+ channels

BACKGROUND

Atrial fibrillation (AF) contributes significantly to morbidity and mortality in elderly patients and has been correlated with enhanced age-dependent atrial fibrosis. Reversal of atrial fibrosis has been proposed as therapeutic strategy to suppress AF.

OBJECTIVE

To test the ability of relaxin to reverse age-dependent atrial fibrosis and suppress AF.

METHODS

Aged F-344 rats (24 months old) were treated with subcutaneous infusion of vehicle or relaxin (0.4 mg/kg/day) for 2 weeks. Rat hearts were excised, perfused on a Langendorff apparatus, and stained with voltage and Ca(2+) indicator dyes. Optical mapping and programmed electrical stimulation was used to test arrhythmia vulnerability and changes in electrophysiological characteristics. Changes in protein expression and Na(+) current density (INa) were measured by tissue immunofluorescence and whole-cell patch clamp technique.

RESULTS

In aged rats, sustained AF was readily induced with a premature pulse (n = 7/8) and relaxin treatment suppressed sustained AF by a premature impulse or burst pacing (n = 1/6) (P < .01). Relaxin significantly increased atrial action potential conduction velocity and decreased atrial fibrosis. Relaxin treatment increased Nav1.5 expression (n = 6; 36% ± 10%) and decreased total collagen and collagen I (n = 5-6; 55%-66% ± 15%) in aged atria (P < .05) and decreased collagen I and III and TGF-β1 mRNA (P < .05). Voltage-clamp experiments demonstrated that relaxin treatment (100 nM for 2 days) increased atrial INa by 46% ± 4% (n = 12-13/group, P < .02).

CONCLUSION

Relaxin suppresses AF through an increase in atrial conduction velocity by decreasing atrial fibrosis and increasing INa. These data provide compelling evidence that relaxin may serve as an effective therapy to manage AF in geriatric patients by reversing fibrosis and modulating cardiac ionic currents.