Echocardiographic myocardial work indices outperform ejection fraction in sepsis heart failure study

The research, published in the journal Cardiovascular Ultrasound, enrolled 180 patients admitted with sepsis to the intensive care unit of the General Hospital of Ningxia Medical University between March 2023 and March 2024. Each patient underwent transthoracic echocardiography on days one, three, and five after admission. Patients were also classified into a survival group and an event group based on their 28-day outcomes.

The technique at the center of the study is known as myocardial work analysis. The analysis uses speckle-tracking echocardiography to measure global longitudinal strain, and the software determines mitral and aortic valve opening and closing times from pulse-wave Doppler before the patient's brachial systolic and diastolic blood pressures are entered to obtain the myocardial work parameters. The software yields four indices: global work index, representing the area of the pressure-strain loop and denoting the stroke work of the left ventricle during systole; global constructive work, the work contributing to ejection; global wasted work, calculated as global work index minus global constructive work and representing the work opposing ejection; and global work efficiency, defined as global constructive work divided by the sum of global constructive work and global wasted work, expressed as a percentage. The authors describe myocardial work indices as an innovative echocardiographic technique that combines left ventricular deformation and afterload parameters, providing a more comprehensive evaluation of the myocardium and a more physiologic assessment of myocardial performance than strain alone, which is itself influenced by afterload.

Compared with sepsis patients whose hearts were spared, those with sepsis-induced cardiomyopathy showed significantly lower global work index, global constructive work, and global work efficiency, along with significantly higher global wasted work, with all differences reaching a statistical threshold of P less than 0.01. The same pattern separated survivors from the event group: work indices were markedly depressed in patients who fared badly, while peak systolic strain dispersion, a marker of mechanical asynchrony, was significantly increased. Conventional measures told a parallel but blunter story, with stroke volume, ejection fraction, lateral e’ velocity, and tricuspid annular plane systolic excursion all reduced in the cardiomyopathy group.

To evaluate the diagnostic utility of the parameters for SICM-LVSD and their prognostic value in sepsis patients, the researchers generated receiver operating characteristic curves and calculated sensitivity, specificity, accuracy, and optimal cutoff values. For diagnosing left ventricular systolic dysfunction in sepsis-induced cardiomyopathy, global longitudinal strain performed best, with an area under the curve of 0.81, followed by global work index and global constructive work at 0.77 each. Global work efficiency and cardiac troponin I tied at 0.73, NT-proBNP reached 0.72, while the ejection fraction managed only 0.67 and global wasted work 0.61.

Prognosis told a similar tale. In predicting 28-day mortality, global work index led the field with an area under the curve of 0.75, followed by global constructive work at 0.74, global longitudinal strain at 0.72, and global work efficiency at 0.70. NT-proBNP and troponin I showed moderate utility at 0.65 and 0.63, while global wasted work and ejection fraction trailed at 0.59 and 0.57. Logistic regression models, adjusted for age, systolic blood pressure, NT-proBNP, and norepinephrine dose, confirmed that higher values of global work index, constructive work, and efficiency were each associated with a lower risk of 28-day mortality, and restricted cubic spline analyses revealed linear, inverse relationships between these indices and the odds of death.

In this cohort, 102 of the 180 patients, or 56.7 percent, met criteria for sepsis-induced cardiomyopathy, an incidence consistent with earlier reports of roughly 60 percent. Mortality diverged sharply between groups: 7.7 percent among sepsis patients without the syndrome versus 38.2 percent among those with it. Because SICM is characterized as transient and reversible myocardial dysfunction, early detection matters, and the authors state that myocardial work indices can detect subclinical left ventricular systolic dysfunction in SICM patients.

The pathophysiology the authors sketch is intricate. Early sepsis brings vasodilation, loss of vascular tone, and blunted catecholamine responsiveness, which alter circulating volume, flow, and pressure and thereby affect myocardial perfusion. The authors describe mitochondrial dysfunction in sepsis as compromising the energy supply to cardiomyocytes, and state that in this state of reduced energy production, sepsis serves as a protective mechanism by suppressing mitochondrial function to reduce oxygen consumption in cardiomyocytes, presenting as myocardial depression. Elevated pulmonary artery systolic pressure, averaging 33 mmHg in the cardiomyopathy group, reduces right ventricular stroke volume and, through ventricular interdependence, raises left ventricular filling pressures. Prolonged strain dispersion signals mechanical asynchrony, in which work performed by timely-contracting segments is wasted on segments relaxing out of sequence. Disrupted lipid and glucose metabolism adds an energy deficit that the authors link to the elevated wasted work and reduced efficiency they observed.

The study is not without caveats, and the authors enumerate them candidly. It was a single-center investigation with a modest sample, raising the possibility of overfitting in the multivariate models and limiting generalizability. The diagnostic standard for the syndrome was a composite based on expert consensus rather than a single gold standard, which may introduce case selection bias. Blood pressure measured by cuff at the brachial artery served as a surrogate for left ventricular systolic pressure, an approximation that ignores vascular compliance and waveform morphology. The analysis did not incorporate a multi-organ dysfunction scoring system, a confounder the authors acknowledge may have inflated the apparent independent prognostic value of the work indices. Only norepinephrine was considered among vasoactive agents, some patients had already received inotropic drugs before imaging, and follow-up stopped at 28 days, leaving long-term cardiac trajectories in survivors unexamined.

Prior work cited by the authors reported that a global work index below 500 mmHg% serves as a predictor for severely reduced left ventricular ejection fraction and indicates a poor prognosis, and a study in dilated cardiomyopathy demonstrated that markedly reduced global work index and global work efficiency suggest significantly impaired left ventricular myocardial systolic function.

Subject of Research: Myocardial work indices for assessing left ventricular systolic dysfunction and predicting 28-day outcomes in sepsis-induced cardiomyopathy

Article Title: Quantitative assessment and prognostic value of myocardial work indices in sepsis-induced cardiomyopathy patients with left ventricular systolic dysfunction

Article References: Yanping, X., Xiaojuan, Y., Jiali, W., Xue, Y., Lu, P., Xiaohong, W., Ying, Y., Ying, W., Wei, C., & Lisha, N. (2026). Quantitative assessment and prognostic value of myocardial work indices in sepsis-induced cardiomyopathy patients with left ventricular systolic dysfunction. Cardiovascular Ultrasound, 24(1), Article 9. https://doi.org/10.1186/s12947-026-00370-w

Image Credits: AI Generated

DOI: 10.1186/s12947-026-00370-w

Keywords: sepsis, sepsis-induced cardiomyopathy, myocardial work indices, echocardiography, left ventricular systolic dysfunction, global work index, global constructive work, global work efficiency, global longitudinal strain, ejection fraction, 28-day mortality, intensive care unit