This Week In HRV Edition

Studies & Resources Discussed

1. HRV Biofeedback for PTSD & Chronic Pain

   • Publication: Journal of Affective Disorders

   • Title: "Heart rate variability biofeedback improves co-occurring posttraumatic stress disorder and chronic pain symptoms: A randomised waitlist controlled trial"

   • Key Finding: This is the first RCT for this co-occurring population. Just six weeks of HRV biofeedback (HRVBF) led to a 24.3% decrease in PTSD symptoms and a 24.9% reduction in pain interference.

2. Biofeedback in Pediatric Care

   • Publication: Cleveland Clinic ConsultQD

   • Title: "Biofeedback Interventions With Psychotherapy in Pediatric Care: The Present and the Future"

   • Key Finding: A clinical guide and call to action for integrating biofeedback (like HRV) with psychotherapy to make self-regulation a concrete, measurable skill for children (e.g., pairing HRV biofeedback with exposure therapy for phobias).

3. Slow-Paced Contraction (SPC)

   • Publication: Biosourcesoftware.com

   • Title: "Add Slow-Paced Contraction to Your Practice"

   • Key Finding: This article details the "how-to" for Slow-Paced Contraction, a vital alternative to slow-paced breathing for patients with contraindications (like severe COPD, kidney disease, or metabolic acidosis).

4. Tai Chi & HRV

   • Publication: Medicine

   • Title: "Effects of a Tai Chi dance intervention on the autonomic nervous system in university students"

   • Key Finding: A 16-week Tai Chi intervention was shown to be an effective method to prevent excessive declines in resting HRV in university students, building autonomic resilience.

5. HRV & Non-Suicidal Self-Injury (NSSI)

   • Publication: Taylor & Francis Online

   • Title: "Association between heart rate variability and emotion dysregulation in adolescents with non-suicidal self-injury"

   • Key Finding: This review frames reduced HRV as a key physiological marker of the Emotion Dysregulation and autonomic imbalance that underlies the distress leading to NSSI in adolescents.

6. HRV in IPV Offenders

   • Publication: Journal of Criminal Justice

   • Title: "Diminished vagally mediated heart rate variability in a compassion-eliciting task in intimate partner violence offenders"

   • Key Finding: Intimate Partner Violence (IPV) offenders showed lower vagally mediated HRV during a compassion-eliciting task, suggesting a diminished physiological capacity to connect with others' suffering.

7. HRV & Heart Failure (HFrEF)

   • Publication: Current Cardiology Reviews (via PMC)

   • Title: "Heart Rate Variability and Heart Failure with Reduced Ejection Fraction: A Systematic Review of Literature"

   • Key Finding: A systematic review concluding that autonomic impairment (low HRV) is a hallmark of HFrEF and that abnormally low HRV metrics are a powerful predictor of worse prognosis.

8. HRV & Subclinical Thyroid Dysfunction

   • Publication: Egyptian Journal of Radiology and Nuclear Medicine

   • Title: "Heart rate variability and left atrial stiffness index... in subclinical thyroid dysfunction"

   • Key Finding: Even subclinical thyroid disorders are linked to increased left atrial stiffness (heart stress). The subclinical hyperthyroid group also showed a significantly increased LF/HF ratio, indicating sympathetic dominance.

9. Predicting Vasovagal Syncope

   • Publication: European Heart Journal

   • Title: "An autonomic function-based prediction model for cardioinhibitory vasovagal syncope"

   • Key Finding: Standard HRV metrics could not differentiate syncope subtypes, but a related metric, Deceleration Capacity (DC), was a significant predictor, leading to a functional predictive model.

10. HRV at High Altitude

    • Publication: Journal of Family Medicine and Primary Care

    • Title: "Normative data of heart rate variability in healthy populations residing at high altitudes..."

    • Key Finding: This study establishes new HRV norms for a population living at 3500m, confirming their values differ from sea-level norms. It also found higher parasympathetic tone (RMSSD, pRR50) in females than males.

11. HRV & Cognitive Workload

    • Publication: BMC Nursing

    • Title: "An integrative review of cognitive workload assessment for safety management"

    • Key Finding: This review identifies ECG (for HRV), EEG, and EOG as the top three preferred physiological signals for objectively assessing cognitive workload in real-time, moving beyond subjective surveys.

12. HRV & Shamanic Journeying

    • Publication: Frontiers in Psychology

    • Title: "Dynamic changes in cardiac function during shamanic journeying and Qigong meditation"

    • Key Finding: A fascinating single-case study tracking HRV during shamanic states. Shamanic drumming, for example, decreased heart rate but increased parasympathetic metrics (RMSSD, pNN50), showing a unique physiological profile.