Valsalva SBP Drop and LVOT Obstruction

Safety and Efficacy of Non-invasive and Ambulatory Hemodynamic Monitoring for Evaluating the Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy

This study aimed to evaluate the efficacy of non-invasive dynamic blood pressure monitoring in assessing left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy. We prospectively collected SBP waveforms and LVOT gradient data from patients with obstructive and non-obstructive disease, systematically analyzed their correlation, and explored its clinical value in different clinical scenarios.

Study Overview

• Status: Recruiting
• Conditions: HCM; oHCM; nHCM
• Intervention / Treatment: Other: participants are not assigned an intervention as part of the study

Detailed Description

Research Background

Left ventricular outflow tract obstruction (LVOTO) is a common pathophysiological change in various cardiac diseases (e.g., hypertrophic obstructive cardiomyopathy, aortic stenosis, etc.). It impedes cardiac ejection and severely affects patient prognosis.Currently, the measurement of LVOTG ≥ 30 mmHg by echocardiography is the gold standard in clinical practice for evaluating the diagnostic value of SBP waveform typing for LVOTO. However, this method is complex to operate, relies on physician experience, and does not allow continuous dynamic monitoring, which limits its application in long-term follow-up and timely adjustment of treatment regimens.Although arterial systolic blood pressure (SBP), as a key hemodynamic indicator, may be associated with the severity of LVOTO (i.e., left ventricular outflow tract gradient, LVOTG), the specific relationship, dynamic change pattern, and clinical applicability between them remain unclear.

Research Objectives

This study aims to evaluate the effectiveness of non-invasive dynamic blood flow monitoring techniques in assessing left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy. By prospectively collecting SBP waveform and LVOTG data from patients with obstructive and non-obstructive conditions, we will systematically analyze their correlation and explore their application value in different clinical scenarios.

Study Endpoints

Primary Endpoints

① Correlation coefficient between SBP waveform characteristics and measured LVOTG values;② Sensitivity and specificity of SBP waveforms in differentiating obstructive HCM with left ventricular outflow tract obstruction.

Secondary Endpoints

① Differences in SBP waveform parameters (e.g., waveform peak, waveform duration, etc.) between obstructive and non-obstructive groups;② Consistency between SBP waveform typing and results of traditional clinical imaging methods (e.g., echocardiography);③ Incidence of procedure-related adverse events.

Study Design

This is a prospective, single-center, observational, parallel-controlled study. SBP waveform and LVOTG data will be prospectively collected from obstructive and non-obstructive patients to systematically analyze their correlation.

Gold Standard

Transthoracic echocardiography (TTE) is used as the gold standard in this study.LVOTO is defined as a resting left ventricular outflow tract peak gradient (LVOTG) ≥ 30 mmHg, or an LVOTG ≥ 50 mmHg after provocation testing (e.g., Valsalva maneuver), according to the 2020 ASE guidelines.

• Study Type: Observational
• Enrollment (Estimated): 800

Contacts and Locations

• Study Contact: Name: Ziqing Yu, PhD; Phone Number: +86 18833221133; Email: yu.ziqing@zs-hospital.sh.cn

Study Locations

• China
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 200032
      • Recruiting
      • Zhongshan Hospital
      • Contact: Yixiu Liang, PhD; Phone Number: +86 13566781221; Email: liang.yixiu@zs-hospital.sh.cn

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Probability Sample

Study Population

HCM patients: In this study, transthoracic echocardiography (TTE) was used as the gold standard. Left ventricular outflow tract obstruction (LVOTO) was defined as a resting left ventricular outflow tract gradient (LVOTG) ≥ 30 mmHg, or an LVOTG ≥ 50 mmHg after provocation tests (e.g., Valsalva maneuver), according

Description

Inclusion Criteria:1: ① Age ≥ 18 years

2: ② Diagnosed with hypertrophic cardiomyopathy (HCM) by echocardiography, with or without left ventricular outflow tract obstruction

3: ③ Conscious and mentally competent, able to understand and voluntarily sign the informed consent form

4: ④ Able to cooperate with the completion of provocation tests, non-invasive dynamic hemodynamic monitoring, and relevant follow-up examinations.

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Exclusion Criteria:

• 1: ① Age ≤ 18 years, or pregnant/lactating patients

  2: ② Presence of other organic heart or great vessel diseases that cause left ventricular outflow tract obstruction, such as severe aortic stenosis, congenital subaortic membrane, etc.

  3: ③ Complicated with persistent atrial fibrillation or other severe arrhythmias that may affect the accuracy of hemodynamic monitoring

  4: ④ Previous history of interventional or surgical therapy for left ventricular outflow tract obstruction, including septal ablation or myectomy

  5: ⑤ Patients with other conditions considered inappropriate by the investigators (e.g., those with absolute or relative contraindications to provocation tests)

  6: ⑥ Patients currently participating in other clinical studies.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
HCM; HCM patients	Other: participants are not assigned an intervention as part of the study; participants are not assigned an intervention as part of the study

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sensitivity and specificity of SBP waveform in differentiating obstructive HCM caused by left ventricular outflow tract obstruction	Sensitivity and specificity of SBP waveform in differentiating obstructive HCM caused by left ventricular outflow tract obstruction	1 year

Collaborators and Investigators

• Sponsor: Shanghai Zhongshan Hospital

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: March 15, 2026
• First Submitted That Met QC Criteria: March 15, 2026
• First Posted (Actual): March 19, 2026

Study Record Updates

• Last Update Posted (Actual): March 19, 2026
• Last Update Submitted That Met QC Criteria: March 15, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: KY2026042; Ziqing Yu (Other Identifier: Zhongshan Hospital Fudan University)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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