Introduction of a Vendor-Independent Application for Clinical Generation of Pressure-Volume Loops from Routine Hemodynamic Data: A Methodological Exploration.

Objectives: In the dynamic perioperative setting, changing fluid states complicate determination of ventricular function. This study evaluated the feasibility of clinical ventricular pressure-volume loop (PVL) construction using routine monitoring (echocardiography and invasive pressure monitoring). An application was developed and tested with biventricular simulated data and right ventricular (RV) clinical data.

Design: Prospective observational study.

Setting: Single center, university teaching hospital.

Participants: Adults requiring cardiac surgery.

Interventions: After code development, a simulated dataset (Harvi simulator) was used to test the application. Next, RV data from 12 consenting adult elective cardiac surgery patients were analyzed in 4 distinct physiologic settings, comparing supine baseline condition with a passive leg raise setting, during maintained elevated positive end-expiratory pressure (PEEP), and after chest wall opening.

Measurements And Main Results: Overall PVL feasibility combining 3 acquisitions was 97.6%. Derived PVL parameters followed expected patterns: during leg raise, end-diastolic volume (+36 ± 23%; p = 0.0054) and stroke volume (+32 ± 27%; p = 0.017) augmented with stable heart rate (HR), resulting in a trend toward increased cardiac output (+34 ± 33%; p = 0.06). PEEP resulted in a marked increase in arterial elastance (+126 ± 80%; p = 0.0000068) compared to the other conditions. Chest opening resulted in minor effects.

Conclusions: This study introduces a vendor-independent application to generate PVLs from routinely available clinical data. The results highlight the potential application of the pressure-volume framework in cardiovascular research and patient care. A lack of external validation must be taken into account. Further research is warranted to validate the application. The app can be accessed at https://michael-vandenheuvel.shinyapps.io/eMv_Looper/.