Ultra Short Heart Rate Variability as a Prognostic Marker in Pulmonary Embolism: A Retrospective Cohort Study

Area of Science:

• Cardiology
• Autonomic Nervous System Research
• Pulmonary Medicine

Background:

• Pulmonary embolism (PE) is a major cause of cardiovascular mortality, necessitating accurate risk stratification.
• Heart rate variability (HRV), an indicator of autonomic function, has potential prognostic value in cardiovascular diseases but is understudied in PE.
• Assessing HRV in the emergency department (ED) could offer rapid prognostic insights for PE patients.

Purpose of the Study:

• To investigate the prognostic utility of ultra-short-term HRV indices in predicting mortality in patients presenting with acute PE.
• To differentiate the prognostic value of HRV between oncological and non-oncological PE patient subgroups.
• To explore the association between HRV and short-term (30-day) and medium-term (90-day) mortality in PE.

Main Methods:

• Retrospective cohort study including 233 patients diagnosed with acute PE in the ED.
• Calculation of ultra-short HRV indices (SDNN, RMSSD) from 10-second ECG recordings.
• Multivariate logistic regression and Cox survival analysis to assess the independent predictive value of HRV for mortality, with subgroup analysis for oncological patients.

Main Results:

• Ultra-short HRV indices did not significantly correlate with short-term mortality in the overall PE cohort.
• In non-oncological PE patients, higher SDNN was independently associated with increased 90-day mortality (AOR 1.018, p=0.044).
• HRV demonstrated no predictive value for mortality in oncological PE patients; however, lower HRV correlated with worse survival in both the overall and non-oncological groups, a finding potentially explained by adaptive physiological responses.

Conclusions:

• Ultra-short HRV shows potential for short-term risk stratification in non-oncological PE patients.
• HRV does not appear to have short-term prognostic relevance in oncological PE patients.
• Further research is needed to understand the paradoxical findings and the role of adaptive HRV in PE prognosis.