What is the clinical evidence from this study?

Study design: Observational. Population: Hypertrophic obstructive cardiomyopathy (HOCM) (n=41). Intervention: Septal myectomy vs. Pre-operative baseline. Primary outcome: Corrected global work index (GWI) in mmHg% (p=<0.001).

What question did this study set out to answer?

This research aims to assess left ventricular function and myocardial fibrosis using corrected myocardial work in HOCM patients.

April 4, 2026Open Access

Evaluating left ventricular function and myocardial fibrosis in hypertrophic obstructive cardiomyopathy with corrected myocardial work

Q: What are the key findings of this study?

Corrected global work index significantly decreased from 2263 to 1273 mmHg% after septal myectomy and was independently associated with the extent of myocardial fibrosis in HOCM patients.

Q: What question did this study set out to answer?

This research aims to assess left ventricular function and myocardial fibrosis using corrected myocardial work in HOCM patients.

Key Result

Corrected global work index significantly decreased from 2263 to 1273 mmHg% after septal myectomy and was independently associated with the extent of myocardial fibrosis in HOCM patients.

Key Points

This research aims to assess left ventricular function and myocardial fibrosis using corrected myocardial work in HOCM patients.
Conducted a prospective study with 41 HOCM patients undergoing septal myectomy.
Utilized transthoracic echocardiography preoperatively and at 3-6 months post-surgery.
Analyzed parameters like global work index, global constructive work, and the degree of myocardial fibrosis.
Noninvasive left ventricular systolic pressure estimation showed a strong correlation with invasive measurements (r = 0.98).
Post-surgery, global work index, global constructive work significantly decreased while global wasted work increased.
Corrected global work index and global constructive work were independently associated with the extent of myocardial fibrosis (R²=0.22 and R²=0.25, respectively).

Study Design

Type

Observational (n=41)

Blinding

Single-blind

Multicenter

Structured PICO

Does corrected myocardial work accurately evaluate left ventricular mechanical remodeling and correlate with myocardial fibrosis in patients with HOCM undergoing septal myectomy?

Population

41 patients with hypertrophic obstructive cardiomyopathy (HOCM) scheduled for septal myectomy (SM), median age 53, 65.9% male. Inclusion criteria: unsatisfactory symptoms despite optimal medical treatment and LVOT gradients ≥ 50 mmHg at rest or after provocation. Exclusion criteria: age < 18 years, midventricular obstruction, arrhythmia, concomitant moderate or severe aortic disease, and poor image quality.

Intervention

Septal myectomy (SM) followed by transthoracic echocardiography at 3-6 months, with left ventricular function evaluated using corrected myocardial work (MW) indices (noninvasive LVSP estimated by adding systolic blood pressure to peak LVOT gradient).

Comparator

Pre-operative baseline (for pre/post SM comparison) and uncorrected MW indices (for method validation).

Outcome

Characteristics of left ventricular myocardial mechanical remodeling (GWI, GCW, GWW, GWE) and correlation between corrected MW parameters and histological myocardial fibrosis (MF).surrogate

Corrected myocardial work indices, specifically GWI and GCW, provide a noninvasive method to assess left ventricular mechanical remodeling and independently correlate with the degree of myocardial fibrosis in HOCM patients.

Main Result

Absolute Event Rate: 1273% vs 2263%

p-value: p=<0.001

Limitations

Single-center study with a small sample size
Invasive pressure assessments were not possible in 50% of the patients, potentially leading to selection bias
Temporal phase misalignment when using peak LVOT gradient and arterial SBP for non-invasive estimation of LVSP
Pharmacological agents during anesthesia may have affected cardiac function and hemodynamic status

Abstract

Echocardiographic Myocardial work (MW) has potential value in hypertrophic obstructive cardiomyopathy (HOCM). This study aimed to utilize corrected MW indices to characterize left ventricular (LV) myocardial mechanical remodeling and evaluate the extent of myocardial fibrosis (MF) in patients with HOCM. We prospectively studied 41 patients with HOCM undergoing septal myectomy (SM). 21 patients underwent intraoperative invasive pressure measurement to validate the noninvasive left ventricular systolic pressure (LVSP) estimation and corrected MW analysis methods. Transthoracic echocardiography was performed in all patients at baseline and 3–6 months after SM. Preoperative and postoperative parameters such as global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were analyzed to investigate the characteristics of LV myocardial mechanical remodeling. The degree of histological MF was evaluated to determine the correlation between corrected MW parameters and MF. Noninvasive LVSP estimated by adding systolic blood pressure to the peak LV outflow tract gradient was well consistent with invasively measured LVSP (r = 0.98, P < 0.001; ICC = 0.96, P < 0.001). After SM, GWI, GCW, and GWE were significantly decreased (all P < 0.001), and GWW was significantly increased in HOCM patients (P = 0.002). Postoperatively, all patients exhibited new-onset complete left bundle branch block. Corrected GWI (R²=0.22, P = 0.002) and GCW (R²=0.25, P < 0.001) were independently associated with the extent of MF. We validated a corrected method for analyzing MW in HOCM patients. HOCM patients may experience reduced metabolism and compromised contraction coordination after SM. GWI and GCW are associated with the level of MF.

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