Acute Effect of Nurse-assessed Remote Ischemic Preconditioning on Improving Vascular Parameters in Patients With Suspected Heart Failure With Preserved Ejection Fraction

Acute Effect of Nurse-assessed Remote Ischemic Preconditioning on Improving Vascular Parameters in Patients With Suspected Heart Failure With Preserved Ejection Fraction

The PIRIC-FEp study will be a randomized clinical trial in sedentary patients with suspected heart failure with preserved ejection fraction.

Objectives: 1) To evaluate the acute efficacy of remote ischemic preconditioning performed by nurses, a noninvasive cardioprotective intervention that uses cycles of ischemia and reperfusion in the extremities, in improving vascular parameters.

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. The control group will receive no intervention. All participants will be examined, at baseline, 0 minutes post intervention, 30 minutes post intervention, 60 minutes post intervention and 24 hours post intervention. Different vascular parameters will be evaluated, including peripheral and central Systolic and Blood Pressure, peripheral and central Mean Arterial Pressure, peripheral and central Pulse Pressure, Heart Rate, Cardiac Output, Stroke Volume, Peripheral Vascular Resistance, aortic Pulse Wave Velocity and Augmentation Index normalized to a heart rate of 75 beats per minute. 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.

Inclusion Criteria:

1. Signs and symptoms of Heart Failure (Clinical suspicion of Heart Failure)
2. Sedentary men and women (structured exercise <2 x 30 min/week).
3. Age ≥40 years
4. Written informed consent
5. Clinically stable for 6 weeks
6. Optimal medical treatment for ≥6 weeks.

Exclusion Criteria:

1. Non-cardiac causes of Heart Failure symptoms:

   • Significant valvular or coronary artery disease
   • Uncontrolled hypertension or arrhythmias
   • Primary cardiomyopathies

2. Significant pulmonary disease (FEV1<50% predicted, GOLD III-IV)

3. Inability to exercise or conditions that may interfere with exercise intervention.

4. Myocardial infarction within the last 3 months.

5. Patients with diabetes and/or peripheral vascular disease.

6. Comorbidity that may influence prognosis at one year.

7. Participation in another clinical trial