Effect of Nurse-assessed Remote Ischemic Preconditioning on Improving Exercise Capacity, Endothelial Function, and Arterial Stiffness in Patients With Heart Failure With Preserved Ejection Fraction

The PIRIC-FEp study will be a randomized clinical trial in sedentary patients with heart failure and stable preserved ejection fraction. Objectives: 1) To evaluate the efficacy of remote ischemic preconditioning performed by nurses, a noninvasive cardioprotective intervention that uses cycles of ischemia and reperfusion in the extremities, in improving exercise capacity, cardiac function, endothelial function and arterial stiffness, and 2) To analyze its impact on quality of life and its cost-effectiveness compared to conventional treatment. Methodology: Patients will be recruited in Health Centers in the city. Those assigned to the intervention group will wear a self-administered blood pressure cuff, inflated to 220 mmHg for 5 minutes, followed by 5 minutes of deflation, in repeated cycles four times, five days a week for three months. The control group will receive standard counseling. All participants will be examined, at baseline and at three months. Adherence will be defined as completing at least 70% of the sessions. Different parameters will be evaluated, including sociodemographic variables, patient's medical history, echocardiography, cardiopulmonary exercise test, endothelial function, arterial stiffness, quality of life, spirometry, blood tests, among others. The study will be approved by an Ethics Committee, participants will be informed and will have to sign a written consent. The statistical analysis will include three phases: verification of randomization, use of covariance models for dependent variables, and sensitivity analysis with propensity score matching. All analyses will be performed on an intention-to-treat basis.