Isabella Fumarulo (1), Antonella Lombardo (1), Barbara Garramone (1), Giulia Iannaccone (1), Massimiliano Camilli (1), Marcello Vaccarella (1), Giovanni Tonti (1), Elia Nunzio Maria Salerno (1), Francesco Burzotta (1), Nadia Aspromonte (1)

(1) Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy

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Background: CCM is a new treatment for HF, which has demonstrated to improve the quality of life and exercise capacity in symptomatic patients in sinus rhythm with LVEF <45% and QRS <130 ms; these improvements cannot completely be explained by the slight improvement in EF and the real impact of CCM on hemodynamics is not clear, yet. Ventricular pressure-volume loop, arterial and ventricular elastances and their coupling (AVC), cardiac mechanical efficiency and stroke work (SW) are physiological variables of great significance in the understanding of the heart function. At present, the effect of CCM on HF patients in terms of arterial and ventricular elastances, AVC, and energetic efficiency has never been evaluated.

Purpose: We aim to assess the evolution over time of ventricular energetics parameters in HF patients who underwent implantation of CCM.

Methods: We conducted a retrospective single-center clinical study enrolling all consecutive adult patients affected by chronic HF who underwent implant of CCM in our institution from December 2020 to September 2024. For all the 20 enrolled patients, clinical and echocardiographic data were collected before implantation of the CCM device and at two consecutive follow-ups. Clinical and echocardiographic data were used to calculate energetics parameters using the software “QStrain Echo, Medis Medical Imaging”.

Results: At the first follow-up we observed a statistically significant improvement in NYHA class (from 2.55 ± 0.51 to 2.10 ± 0.72, p= 0.001). Statistical analysis showed that the mean EF significantly improved from 28,66 (± 9,14) % to 31,75 (± 7.72)% (p= 0.05), as well as the mean GLS (from -8,79 (±2,98) to -10,05 (±3,09), p= 0.004). Also, the mean ESV showed a trend to decrease (from 109,17 (± 51,71) ml to 104,53 (±52,03) ml) although the difference resulted to be not statistically significant. Regarding parameters of Ventricular Energetics, at first follow-up, we observed a statistically significant increase in mean lateral-septal strength (from 1.28 ± 0.31 % to 1.55 ± 0.49 %, p= 0.035). We also observed an interesting increase in SW (from 0.46 ±0.17 J to 0.53±0.18 J, p= 0.061). All the other variables did not show a statistically significant difference between baseline and first follow-up, nevertheless we observed a positive trend on apical-basal strength, SV, CO and a better VAC. The statistically significant improvement in NYHA class observed at the first follow-up was confirmed at the second follow-up (from NYHA class 2.53 ± 0.51 to 1.89 ± 0.57, p<0.001). All the other variables did not show a statistically significant difference between first and second follow-up.

Conclusions: The software QStrain Echo allow to investigate patients’ hemodynamics in a totally non-invasive way, providing useful information that can be used to guide clinical management of patients after CCM implantation: through this novel technology the clinician can monitor patients’ hemodynamics during the ordinary follow-up contacts. If the ventricular energetics analysis reveals a worsening in parameters of SV, CO and SW, the clinician could promptly act, optimizing stimulation parameters of CCM, before the clinical worsening. Nonetheless, further studies are necessary in order to confirm this hypothesis.