Effect of Visit‐to‐Visit Variation of Heart Rate and Systolic Blood Pressure on Outcomes in Chronic Systolic Heart Failure: Results From the Systolic Heart Failure Treatment With the
            I
            f
            Inhibitor Ivabradine Trial (SHIFT) Trial

Abstract Background Heart failure (HF) is a major public health problem with increasing prevalence worldwide. It is associated with high mortality and poor quality of life due to recurrent and costly hospital admissions. Several studies have been conducted to describe HF risk predictors in different races, countries and health systems. Nonetheless, understanding population-specific determinants of HF outcomes remains a great challenge. We aim to evaluate predictors of 1-year survival of individuals with systolic heart failure from the GENIUS-HF cohort. Methods We enrolled 700 consecutive patients with systolic heart failure from the SPA outpatient clinic of the Heart Institute, a tertiary health-center in Sao Paulo, Brazil. Inclusion criteria were age between 18 and 80 years old with heart failure diagnosis of different etiologies and left ventricular ejection fraction ≤50% in the previous 2 years of enrollment on the cohort. We recorded baseline demographic and clinical characteristics and followed-up patients at 6 months intervals by telephone interview. Study data were collected and data quality assurance by the Research Electronic Data Capture tools. Time to death was studied using Cox proportional hazards models adjusted for demographic, clinical and socioeconomic variables and medication use. Results We screened 2314 consecutive patients for eligibility and enrolled 700 participants. The overall mortality was 6.8% (47 patients); the composite outcome of death and hospitalization was 17.7% (123 patients) and 1% (7 patients) have been submitted to heart transplantation after one year of enrollment. After multivariate adjustment, baseline values of blood urea nitrogen (HR 1.017; CI 95% 1.008–1.027; p < 0.001), brain natriuretic peptide (HR 1.695; CI 95% 1.347–2.134; p < 0.001) and systolic blood pressure (HR 0.982;CI 95% 0.969–0.995; p = 0.008) were independently associated with death within 1 year. Kaplan Meier curves showed that ischemic patients have worse survival free of death and hospitalization compared to other etiologies. Conclusions High levels of BUN and BNP and low systolic blood pressure were independent predictors of one-year overall mortality in our sample. Trial registration Current Controlled Trials NTC02043431, retrospectively registered at in January 23, 2014.

Download Full-text

Fractal Component of Variability of Heart Rate and Systolic Blood Pressure in Congestive Heart Failure

Clinical Science ◽

10.1042/cs0920543 ◽

1997 ◽

Vol 92 (6) ◽

pp. 543-550 ◽

Cited By ~ 32

Author(s):

Gary C. Butler ◽

Shin-Ichi Ando ◽

John S. Floras

Keyword(s):

Heart Failure ◽

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Systolic Blood Pressure ◽

Spectral Power ◽

Normal Subjects ◽

Total Spectral Power ◽

Systolic Blood Pressure Variability ◽

Harmonic Components

1. There is a substantial non-harmonic or fractal component to the variability of both heart rate and blood pressure in normal subjects. Heart rate is the more complex of these two signals, with respect to the slope, β, of the 1/fβ relationship. In congestive heart failure, heart rate spectral power is attenuated, but the fractal and harmonic components of heart rate and systolic blood pressure variability have not been characterized. 2. Two groups, each comprising 20 men, were studied during 15 min of supine rest and spontaneous respiration: one with functional class II—IV heart failure (age 52 ± 2 years; mean ± SEM) and a second group of healthy men (age 46 ± 2 years). 3. Total spectral power for heart rate was significantly reduced in heart failure (P < 0.02), whereas total spectral power for systolic blood pressure was similar in the two groups. In both heart failure and normal subjects, 65–80% of total spectral power in these two signals displayed fractal characteristics. 4. In heart failure, the slope of the 1/fβ relationship for heart rate was significantly steeper than in normal subjects (1.40 ± 0.08 compared with 1.14 ± 0.05; P < 0.05), indicating reduced complexity of the fractal component of heart rate variability. There was no significant difference in the 1/fβ slope for systolic blood pressure variability between these two groups, but the blood pressure signals were less complex than heart rate variations in both heart failure (2.31 ± 0.15; P < 0.006) and normal subjects (2.47 ± 0.15; P < 0.0001). 5. Parasympathetic nervous system activity, as estimated from heart rate variability was reduced (P < 0.01) in patients with heart failure, whereas trends towards increased sympathetic nervous system activity and decreased non-harmonic power were not significant. 6. The non-harmonic components of cardiac frequency are reduced in heart failure. Non-harmonic power is not attenuated, but the complexity of the heart rate signal is less than in subjects with normal ventricular function. A reduction in parasympathetic modulation appears to contribute to this loss of complexity of heart rate. Consequently, the heart rate signal comes to resemble that of blood pressure. In contrast, the variability and complexity of the systolic blood pressure signal is similar in heart failure and normal subjects. This reduced complexity of heart rate variability may have adverse implications for patients with heart failure.

Download Full-text