Abstract 13817: Very Short-Term Blood Pressure Variability by Pulse Transit Time-Based Measurements During Sleep Predicts Future Cardiovascular Events in Patients With Ischemic Heart Disease

Background: Blood pressure (BP) variability (BPV) is recognized as an independent factor associated with cardiovascular (CV) events. However, monitoring very short-term BPV, which occurs within seconds or minutes remains challenging, and its prognostic impact has yet to be established. In a previous study, we reported that pulse transit time (PTT) enabled monitoring beat-to-beat BP, which is useful for evaluating very short-term BPV during sleep. Aims: This study aimed to clarify the prognostic relevance of PTT-based very short-term BPV during sleep. Methods and Results: We conducted a prospective study involving 206 consecutive hospitalized patients (mean 67.6 years old, 78.1% male) with ischemic heart disease. PTT-driven BP was continuously recorded during the night. To assess very short-term BPV, we defined the PTT index as the average number of acute transient rises in systolic BP (≥12 mmHg) within 30 s/h, and the standard deviation (SD) of PTT-BP was calculated. We followed up with patients for a median of 759 days and observed 49 CV events, including cardiac death, worsening heart failure, acute coronary syndrome, and ischemic stroke. Kaplan-Meier analysis revealed that patients with higher PTT index, as well as higher SD of mean and diastolic PTT-BP were associated with increased CV events ( Figure ). In a multivariate Cox proportional hazards analysis, after adjusting for confounding variables, PTT index, as well as SD of mean and diastolic PTT-BP were independently associated with increased risks of adverse events (hazard ratio, 1.019, 1.245, and 1.244; P = 0.02, 0.04, and 0.09, respectively). Conclusions: PTT-index and SD of mean and diastolic BP during the night, which represent measures of very short-term BPV, predicted the future risk of CV events in patients with ischemic heart disease through the PTT-driven approach and may serve as a target to reduce the residual risk in such patients.