NCT06154642

Perioperative Hemodynamic and Microcirculatory Physiological Study During TAVI

Physiological Study of Hemodynamic and Microcirculatory Evolution Before/After Transcatheter Aortic Valve Replacement (TAVI)

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 21 (actual)
• Sponsor: University Hospital, Geneva · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The Physiological Study of Haemodynamic and Microcirculatory Evolution before/after Transcatheter Aortic Valve Replacement (TAVI) aims to investigate the physiological changes induced by the implantation of a prosthetic aortic valve on blood vessels in patients with severe aortic stenosis. The hypothesis of the study is that adaptive microcirculatory phenomena occur during TAVI implantation. The results of preoperative assessment of microcirculatory functional reserve differ according to whether or not organ dysfunction occurs after TAVI. There is a progressive adaptation of the microcirculation to the new cardiovascular load conditions after TAVI. Early features of this adaptation are associated with the occurrence of short- and medium-term complications.

Detailed description

This is a prospective, physiologic, monocentric, pilot cohort study carried out at the University Hospitals of Geneva on the initiative of the investigator. We are investigating the adaptive mechanisms at work in the blood vessels and their potential impact on clinical outcomes in the month following surgery. In addition to the usual perioperative monitoring, patients enrolled in the study will benefit from vascular monitoring, which consists of a series of additional non-invasive and painless examinations performed before, a few hours after and on the day after surgery. The clinical outcome of the aortic valve implantation will be monitored by a questionnaire on the day after the procedure, a 6-minute walk test during the usual consultation with the cardiologist on the 6th day after the procedure, and a review of patient health events one month after the valve implantation.

Conditions

• Aortic Valve Stenosis

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Determination of arterial compliance using blood pressure waveform analysis	Measurement of arterial stiffness using a non-invasive pressure transducer placed on the skin of the wrist, which records the pulse wave at the level of the radial artery in order to analyze the characteristics of the arterial wall. The parameters of interest are the arterial stiffness of large- and small-caliber arteries (ml/mmHg).
DIAGNOSTIC_TEST	Measurement of plasma Vascular Endothelium Growth Factor	Measurement of plasma Vascular Endothelium Growth Factor levels by ELISA
DIAGNOSTIC_TEST	Skin temperature gradient	Measurement of skin surface temperature gradient, defined as the difference in temperature between the skin surface of the forearm and that of the fingertip (forearm-to-fingertip)
DIAGNOSTIC_TEST	Vaso-occlusion test	Measurement of endothelial function by a vaso-occlusion test performed by inflating a cuff on the arm to occlude arterial flow for 3 min. Reactive hyperemia on deflation of the cuff is measured by photoplethysmography placed on the index finger, and tissue oxygen saturation (StO2) by near-infrared spectroscopy (NIRS). The amplitude of the reperfusion flow corresponding to the peak of the perfusion index (ΔPI Peak) and the time to reach this peak (time to peak) are the parameters recorded by photoplethysmography. Tissue resaturation rate (rStO2) is the parameter recorded by NIRS.
DIAGNOSTIC_TEST	Transthoracic echocardiography	The diameter of the left ventricular outflow tract is measured in the tele systolic parasternal long-axis view. The pulsed Doppler flow profile is acquired at the level of the left ventricular chamber in the apical five-chamber view. The time-velocity integral of the aortic flow is then calculated. Left ventricular end-diastolic and end-systolic volumes are also measured using Simpson's method in the 4-cavity monoplane view. Measurements of vena cava diameter and respiratory variability of vena cava diameter provide an estimate of right atrial pressure. These measurements estimate cardiac output and systemic vascular resistance.
DIAGNOSTIC_TEST	Photoplethysmography	The perfusion index (PI) is derived from the signal and represents the ratio between the absorbance or reflectance of pulsatile and non-pulsatile light of the photoplethysmography signal. PI is measured non-invasively using a photoplethysmographic sensor placed on the earlobe or finger.
PROCEDURE	Transcatheter aortic valve insertion (TAVI)	TAVI is a treatment for aortic valve stenosis. A new valve is inserted with minimally invasive procedure without removing the old, damaged valve.

Timeline

• Start date: 2024-05-08
• Primary completion: 2024-06-13
• Completion: 2024-07-13
• First posted: 2023-12-04
• Last updated: 2024-08-06

Locations

1 site across 1 country: Switzerland