The association between a simple measure of QRS voltage and the in-hospital mortality of acutely ill medical patients

Early detection of low QRS voltage and its association with mortality in patients with sepsis

Various electrocardiographic changes occur during sepsis, but data on the clinical importance of a low QRS voltage in sepsis are still limited. We aimed to evaluate the association between low QRS voltage identified early in sepsis and mortality in patients with sepsis. Between September 2019 and December 2020, all consecutive adult patients diagnosed with sepsis in the emergency room or general ward at Samsung Medical Center were enrolled. Patients without a 12-lead electrocardiogram recorded within 48 h of recognition of sepsis were excluded. In 432 eligible patients, 12-lead electrocardiogram was recorded within the median of 24 min from the first recognition of sepsis, and low QRS voltage was identified in 115 (26.6%) patients. The low QRS group showed more severe organ dysfunction and had higher levels of N-terminal pro-brain natriuretic peptide. The hospital mortality was significantly higher in the low QRS voltage group than in the normal QRS voltage group (49.6% vs. 28.1%, p < 0.001). Similarly, among the 160 patients who required intensive care unit admission, significantly more patients in the low QRS group died in the intensive care unit (35.9% vs. 18.2%, p = 0.021). Low QRS voltage was associated with increased hospital mortality in patients with sepsis.

Relation of QRS Voltage and Prolonged QTc Interval to One-Year Mortality

The association between QRS voltage and QTc interval prolongation with mortality for up to 1 year after recording an ECG on patients attending emergency departments (EDs) was examined in a retrospective register-based observational study on 37,473 patients attending 2 Danish EDs. Of 37,473 patients who had an ECG performed on their first ED presentation 2,164 (5.8%) died within 30 days of presentation and 6,395 (17.1%) died within a year. Compared with survivors, patients who died had significantly longer QRS intervals and lower QRS voltages. A combined lead I and II QRS voltage <=1.4 mV was consistently associated with approximately twice the risk of mortality for up to at least 1 year after the ECG recording and this risk was not influenced by the length of the QTc interval. The increased mortality risk of a low QRS voltage remained even after adjustment for age, gender, Charlson co-morbidity index, and abnormal sodium and urea levels. In conclusion, low QRS voltage is a simple measurement that could potentially be used as an objective prognostic marker.

Low voltage on the 12-lead ECG: A warning sign

A 12-lead ECG showing low voltage should be a red flag to providers; it can be caused by several serious conditions. This clinical case describes how an NP correctly treated a patient with low voltage on an ECG by discerning and managing the underlying causes.

QRS voltage is a predictor of in-hospital mortality of acutely ill medical patients

BACKGROUND

Low QRS voltage has been shown to be associated with increased mortality in the general population and in a small pilot study the combined QRS voltage of ECG leads I and II was found to be associated with in-hospital mortality.

HYPOTHESIS

Confirm that low QRS voltage predicts the in-hospital mortality of acutely ill patients, and compare QRS voltage with other predictors of mortality that can be easily, quickly and cheaply obtained at the bedside.

METHODS

Prospective observational study of vital signs, QRS voltage and simple tools used to assess mental, functional and nutritional status at the bedside in unselected acutely ill patients admitted to a resource-poor hospital in sub-Saharan Africa.

RESULTS

Out of 1486 patients, 77 died (5.2%) in hospital. A combined lead I + II voltage <1.8 mV was present in 789 (53.1%) of patients, and significantly associated with in-hospital mortality (odds ratio 3.6, 95% CI 2.0-6.5, χ² 21.2, P < 0.00001). On logistic regression impaired mobility, the National Early Warning Score, male gender and lead I + II voltage were the only independent predictors of mortality. None of the 445 patients who were mobile on admission with a lead I + II voltage ≥ 1.8 mV died in hospital.

CONCLUSIONS

Low QRS voltage, male gender, NEWS, and impaired mobility were independent predictors of in-hospital mortality in the study population. These four variables, which are easily obtained at the bedside, could potentially provide a rapid, easy, and cheap risk stratification system.