Dietary nitrate supplementation and exercise tolerance in patients with heart failure with reduced ejection fraction.

Endothelial dysfunction and reduced nitric oxide (NO) signaling are key abnormalities leading to skeletal muscle oxygen delivery-utilization mismatch and poor physical capacity in patients with heart failure with reduced ejection fraction (HFrEF). Oral inorganic nitrate supplementation provides an exogenous source of NO that may enhance locomotor muscle function and oxygenation with consequent improvement in exercise tolerance in HFrEF. Thirteen patients (left ventricular ejection fraction ≤40%) were enrolled in a double-blind, randomized crossover study to receive concentrated nitrate-rich (nitrate) or nitrate-depleted (placebo) beetroot juice for 9 days. Low- and high-intensity constant-load cardiopulmonary exercise tests were performed with noninvasive measurements of central hemodynamics (stroke volume, heart rate, and cardiac output via impedance cardiography), arterial blood pressure, pulmonary oxygen uptake, quadriceps muscle oxygenation (near-infrared spectroscopy), and blood lactate concentration. Ten patients completed the study with no adverse clinical effects. Nitrate-rich supplementation resulted in significantly higher plasma nitrite concentration compared with placebo (240 ± 48 vs. 56 ± 8 nM, respectively; P < 0.05). There was no significant difference in the primary outcome of time to exercise intolerance between nitrate and placebo (495 ± 53 vs. 489 ± 58 s, respectively; P > 0.05). Similarly, there were no significant differences in central hemodynamics, arterial blood pressure, pulmonary oxygen uptake kinetics, skeletal muscle oxygenation, or blood lactate concentration from rest to low- or high-intensity exercise between conditions. Oral inorganic nitrate supplementation with concentrated beetroot juice did not present with beneficial effects on central or peripheral components of the oxygen transport pathway thereby failing to improve exercise tolerance in patients with moderate HFrEF.

The nature of telephone nursing interventions in a heart failure clinic setting.

BACKGROUND: There is a lack of published data about the nature of nursing interventions that are required to provide telephone management for patients with heart failure (HF). PURPOSE: The nature of patient issues, telephone nursing interventions, and associated workload at one HF clinic are described in this study. METHODS: Workload was captured using a computerized workload measurement tool. An electronic telephone log categorizing nursing interventions as providing education, changing medication doses, ordering diagnostic tests and consulting with community health care providers, and the scope of practice required to complete the intervention was kept. RESULTS: Nurses spent 24% of their working hours doing 1914 telephone visits in one year. Medications were changed 583 times and diagnostic tests were ordered 207 times. Nurses initiated 65% of calls; others were received from patients, family members, and other health care providers. CONCLUSION: A combination of nurse practitioners and registered nurses with medical directives can address the issues that commonly arise through telephone management of HF patients.

The role and scope of practice of nurses working in Canadian heart failure clinics.

BACKGROUND: Nurses play an integral role in providing care in heart failure (HF) clinics and disease management programs that lead to improved outcomes for HF patients. OBJECTIVES: This pilot study explored how closely nurses in Canadian HF clinics follow consensus guideline recommendations and nursing interventions from published studies. METHODS: A total of 27 nurses from HF clinics across Canada completed a questionnaire about their role and scope of practice. RESULTS: The majority of nurses covered recommended topic areas for counseling and education with the exceptions of discussing advanced directives, teaching patients to titrate diuretics, and counseling on secondary prevention. Nurses with a postgraduate degree were more likely to independently titrate medications and order echocardiograms. Nurses affiliated with the Canadian Congestive HF Clinic Network were more likely to provide telephone management, titrate medications, and order echocardiograms and other diagnostic tests. CONCLUSION: Patients may not be experiencing the benefits that are reported in the literature for being followed up in a HF clinic because the role and scope of practice of nurses varies from one clinic to another. The role and scope of practice of nurses in HF clinics needs to be standardized.