Ventricular-Arterial Coupling: A Predictor of Post-Induction Hypotension (VAC)

Predictive Value of Ventricular-Arterial Coupling for Post-Induction Hypotension: A Prospective Observational Cohort Study

Post-induction hypotension (PIH) is a common occurrence during the period from induction of general anesthesia to initiation of incision. PIH has been identified as an independent risk factor for postoperative major complications. Identifying high-risk patients for PIH could potentially help prevent its occurrence. Several risk factors associated with PIH have been identified, including patient conditions and use of specific anesthetic agents. Ventricular-arterial coupling (VAC) is evaluated using the ratio Ea/Ees and represents the interaction between the left ventricle (LV) and the arterial system. It reflects how changes in LV contractility (Ees) and changes in arterial load (Ea) work together to maintain optimal LV performance. A study aims to investigate the relationship between preoperative Ea/Ees ratio and the incidence of PIH (defined as MAP < 65 mmHg).

Study Overview

• Status: Completed
• Conditions: Hypotension on Induction

Detailed Description

Post-induction hypotension (PIH) is a common event due to general anesthesia in patients undergoing surgery. It is described as hypotension occurring during the period from induction of general anesthesia to initiation of incision. A universal definition of intraoperative hypotension is lacking, leading to inconsistent rates of occurrence for PIH. According to Yoshimura et al., PIH occurs in 34% of patients using the mean arterial pressure (MAP) definition of < 55 mmHg, whereas Maheshwari found PIH in 53% of patients using a MAP definition of < 65 mmHg. Furthermore, Maheshwari et al. demonstrated that PIH was an independent risk factor for postoperative major complications such as myocardial injury, cerebrovascular events, and acute kidney injury.

If high-risk patients for PIH could be identified we might potentially prevent PIH. In a systematic review, Chen et al. pointed out that the risk factors associated with PIH were ASA (American Society of Anesthesiologists) III-V, advanced age, emergency cases, hypovolaemia, long-term use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, use of propofol and high-dose of opioid. This study suggests that PIH may be the result of an interaction between the anesthetic agent and the cardiovascular condition of the patient. Conditions such as moderate-to-severe aortic regurgitation, moderate-to-severe mitral regurgitation, regional wall motion abnormalities, and echocardiography findings (e.g. elevated ratio of peak early diastolic transmitral flow velocity to annular velocity) have been identified as PIH-independent risk factors.

End-systolic elastance (Ees) is a measure of the contractile state of the left ventricle (LV). It represents the relationship between LV end-systolic pressure (LVESP) and end-systolic volume (ESV). Effective arterial elastance (Ea) is a measure of the total arterial load on the LV and is calculated as the ratio of LVESP to stroke volume (SV). Ventricular-arterial coupling (VAC), assessed by the ratio Ea/Ees, describes the interaction between the LV and arterial system. VAC reflects the interplay between the changes in LV contractility (Ees) and changes in arterial load (Ea) to maintain optimal LV performance.

Aktas et al. analyzed Ea as a predictor of PIH. The results of this study showed that pre-induction Ea had excellent predictability of hypotension. However, Ees values were not determined, thus making it speculative to conclude that pre-induction VAC is impaired in patients with high Ea. There are no studies available that assessed the role of preoperative VAC in predicting PIH. Therefore, we will investigate the relationship between the preoperative Ea/Ees ratio and the incidence of PIH (: hypotension being defined as MAP < 65 mmHg).

• Study Type: Observational
• Enrollment (Actual): 475

Contacts and Locations

Study Locations

• Vietnam
  • Ho Chi Minh City, Vietnam
    • University Medical Centre Ho Chi Minh

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients with American Society of Anesthesiologists (ASA) physical status 1 - 4 who underwent elective surgery

Description

Inclusion Criteria:

• Patients ≥ 18 years old.
• Patients with ASA (American Society of Anesthesiologists) physical status 1 - 4.
• Elective non-cardiac, non-obstetric, and non-gynaecologic surgery
• Preoperative transthoracic echocardiography was performed within 48 hours before surgery. The values of Ees and Ea were determined by the method of Chen.
• Patients consented to participate in the study.
• Patients scheduled for surgery undergoing standard general anesthesia (protocol: see below) with endotracheal intubation.
• Patients were hemodynamically stable until the preoperative period.

Exclusion Criteria:

• Uncorrected congenital heart disease, moderate-to-severe valvular disease or pulmonary hypertension, arrhythmias, anticipated difficult airway, and known allergy to anaesthetic agents.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Post-Induction Hypotension	Post-induction hypotension (PIH) was defined according to the protocol criteria and assessed during the interval from induction of anesthesia to surgical incision. The incidence of PIH was calculated as the number of analyzed participants who developed PIH during this interval.	From induction of anesthesia to surgical incision, up to 1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area Under the Receiver Operating Characteristic Curve for Prediction of Post-Induction Hypotension	Predictive performance for post-induction hypotension (PIH) was evaluated using logistic regression models. Model discrimination was assessed using the area under the receiver operating characteristic curve (AUC). Clinical variables, echocardiographic measurements, and ventriculo-arterial coupling (VAC)-related variables were evaluated for prediction of PIH. Higher AUC values indicate better model discrimination.	From induction of anesthesia to surgical incision, up to 1 hour
Fractional New Information Added for Prediction of Post-Induction Hypotension	Incremental predictive value for post-induction hypotension (PIH) was assessed using fractional new information (FNI). FNI was used to quantify the additional predictive information provided by echocardiographic measurements and ventriculo-arterial coupling (VAC)-related variables when added to the clinical prediction model.	From induction of anesthesia to surgical incision, up to 1 hour

Collaborators and Investigators

• Sponsor: University Medical Center Ho Chi Minh City (UMC)
• Investigators: Study Director: Khoi M Le, Assoc.Prof, University Medical Center

Publications and helpful links

General Publications

• Liu N, Chazot T, Genty A, Landais A, Restoux A, McGee K, Laloe PA, Trillat B, Barvais L, Fischler M. Titration of propofol for anesthetic induction and maintenance guided by the bispectral index: closed-loop versus manual control: a prospective, randomized, multicenter study. Anesthesiology. 2006 Apr;104(4):686-95. doi: 10.1097/00000542-200604000-00012.
• Mitchell C, Rahko PS, Blauwet LA, Canaday B, Finstuen JA, Foster MC, Horton K, Ogunyankin KO, Palma RA, Velazquez EJ. Guidelines for Performing a Comprehensive Transthoracic Echocardiographic Examination in Adults: Recommendations from the American Society of Echocardiography. J Am Soc Echocardiogr. 2019 Jan;32(1):1-64. doi: 10.1016/j.echo.2018.06.004. Epub 2018 Oct 1. No abstract available.
• Maheshwari K, Turan A, Mao G, Yang D, Niazi AK, Agarwal D, Sessler DI, Kurz A. The association of hypotension during non-cardiac surgery, before and after skin incision, with postoperative acute kidney injury: a retrospective cohort analysis. Anaesthesia. 2018 Oct;73(10):1223-1228. doi: 10.1111/anae.14416. Epub 2018 Aug 24.
• Avidan MS, Zhang L, Burnside BA, Finkel KJ, Searleman AC, Selvidge JA, Saager L, Turner MS, Rao S, Bottros M, Hantler C, Jacobsohn E, Evers AS. Anesthesia awareness and the bispectral index. N Engl J Med. 2008 Mar 13;358(11):1097-108. doi: 10.1056/NEJMoa0707361.
• Yoshimura M, Shiramoto H, Koga M, Morimoto Y. Preoperative echocardiography predictive analytics for postinduction hypotension prediction. PLoS One. 2022 Nov 28;17(11):e0278140. doi: 10.1371/journal.pone.0278140. eCollection 2022.
• Sudfeld S, Brechnitz S, Wagner JY, Reese PC, Pinnschmidt HO, Reuter DA, Saugel B. Post-induction hypotension and early intraoperative hypotension associated with general anaesthesia. Br J Anaesth. 2017 Jul 1;119(1):57-64. doi: 10.1093/bja/aex127.
• Chen B, Pang QY, An R, Liu HL. A systematic review of risk factors for postinduction hypotension in surgical patients undergoing general anesthesia. Eur Rev Med Pharmacol Sci. 2021 Nov;25(22):7044-7050. doi: 10.26355/eurrev_202111_27255.
• Tarao K, Daimon M, Son K, Nakanishi K, Nakao T, Suwazono Y, Isono S. Risk factors including preoperative echocardiographic parameters for post-induction hypotension in general anesthesia. J Cardiol. 2021 Sep;78(3):230-236. doi: 10.1016/j.jjcc.2021.03.010. Epub 2021 Apr 8.
• Monge Garcia MI, Santos A. Understanding ventriculo-arterial coupling. Ann Transl Med. 2020 Jun;8(12):795. doi: 10.21037/atm.2020.04.10.
• Aktas Yildirim S, Sarikaya ZT, Dogan L, Ulugol H, Gucyetmez B, Toraman F. Arterial Elastance: A Predictor of Hypotension Due to Anesthesia Induction. J Clin Med. 2023 Apr 27;12(9):3155. doi: 10.3390/jcm12093155.
• Chen CH, Fetics B, Nevo E, Rochitte CE, Chiou KR, Ding PA, Kawaguchi M, Kass DA. Noninvasive single-beat determination of left ventricular end-systolic elastance in humans. J Am Coll Cardiol. 2001 Dec;38(7):2028-34. doi: 10.1016/s0735-1097(01)01651-5.
• Cho JY, Kim KH. Evaluation of Arterial Stiffness by Echocardiography: Methodological Aspects. Chonnam Med J. 2016 May;52(2):101-6. doi: 10.4068/cmj.2016.52.2.101. Epub 2016 May 20.
• Guinot PG, Andrei S, Longrois D. Ventriculo-arterial coupling: from physiological concept to clinical application in peri-operative care and ICUs. Eur J Anaesthesiol Intensive Care. 2022 Aug 3;1(2):e004. doi: 10.1097/EA9.0000000000000004. eCollection 2022 Apr.

Study record dates

Study Major Dates

• Study Start (Actual): July 3, 2023
• Primary Completion (Actual): November 20, 2024
• Study Completion (Actual): December 10, 2024

Study Registration Dates

• First Submitted: July 24, 2023
• First Submitted That Met QC Criteria: July 24, 2023
• First Posted (Actual): August 1, 2023

Study Record Updates

• Last Update Posted (Actual): September 15, 2026
• Last Update Submitted That Met QC Criteria: September 13, 2026
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Ventricular-Arterial Coupling (VAC); Ea/Ees ratio; Post-induction hypotension (PIH); Risk factors for PIH
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypotension
• Other Study ID Numbers: 32/GCN-HDDD; No: 32/GCN-HDDD (Other Identifier: University Medical Center Ho Chi Minh City)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Yes, there is a plan to make individual participant data (IPD) available. The de-identified dataset underlying the findings of this study will be shared upon reasonable request. Researchers can request access by contacting chinh.lh@umc.edu.vn. Requests will be reviewed to ensure compliance with ethical and legal standards.
• IPD Sharing Time Frame: After publication of the study. Indefinitely
• IPD Sharing Access Criteria: "Data will be shared upon reasonable request, with approval based on the researcher's qualifications and the purpose of the request." Access will only be granted to academic or non-commercial researchers who meet the conditions outlined in the Data Use Agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No