# Vasodilation and Reduction of Systolic Blood Pressure after One Session of High-Intensity Interval Training in Patients With Heart Failure with Preserved Ejection Fraction

PMID: 30365604
Journal: Arquivos Brasileiros de Cardiologia
Published: 2018-11
Authors: Lima JB, Silveira ADD, Saffi MAL, Menezes MG, Piardi DS, Ramm LDCR, Zanini M, Stein RMNR

## Question

Does one HIIT session acutely improve endothelial function and blood pressure in patients with HFpEF?

## Summary

Sixteen clinically stable patients with heart failure with preserved ejection fraction completed one supervised treadmill HIIT session. The session was tolerated without adverse events and was followed by larger brachial artery diameter and lower systolic blood pressure 30 minutes later, but the study had no control group.

## Population

- Clinically stable patients with heart failure with preserved ejection fraction.
- Sample size: 16
- Age: 59 +/- 7 years
- Sex: 9 women, 7 men
- Fitness level: Low cardiorespiratory fitness; VO2peak 18.40 +/- 3.16 mL/kg/min.
- Health status: HFpEF with high cardiometabolic comorbidity burden.

## Methodology

- Single-arm quasi-experimental before-after study
- One supervised HIIT session with 30-min post-exercise assessment
- Tertiary outpatient cardiology clinic in southern Brazil

## Protocol

- Supervised HFpEF treadmill HIIT.
- Modality: Treadmill.
- Work intervals: 4 min at 85-95% HRmax/Borg 15-17.
- Recovery: 3 min active recovery at 60-70% HRmax/Borg 11-13.
- Sets or repetitions: 4 intervals.
- Intensity: HRmax and Borg targets from CPET.
- Session duration: 36 min.
- Frequency: Single session.
- Program length: Acute.

## Outcomes

### Brachial diameter
Status: improved
Brachial artery diameter increased after HIIT.

3.96 +/- 0.57 to 4.33 +/- 0.69 mm, p<0.01.

### Systolic BP
Status: improved
Systolic BP decreased after HIIT.

About 12.7 +/- 3.8 mmHg reduction at 30 min.

### FMD
Status: no clear change
Relative flow-mediated dilation did not significantly change.

5.91 +/- 5.20% to 3.55 +/- 6.59%, p=0.162.

### Adverse events
Status: improved
All analyzed patients completed the session without adverse events.

16/16 completed.

## Practical Insights

- Clinical 4 x 4-min HIIT can be feasible in carefully selected HFpEF patients under supervision.
- This evidence should inform cautionary clinical context, not consumer-app prescriptions.

## Limitations

- Small sample.
- No control group.
- Single-center clinical population.
- Only acute 30-min follow-up.
- No moderate-intensity comparator.

## Safety And Adherence

- No adverse events occurred during the supervised HIIT session.
- Participants were clinically screened HFpEF patients monitored with ECG, HR, BP, and Borg RPE.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/30365604/) (pubmed)
- [DOI](https://doi.org/10.5935/abc.20180202) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6248251/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.