T end (Te) and Te standard deviation (TeSD) may represent noninvasive clinical markers to predict the risk for in-hospital mortality among patients with decompensated chronic heart failure (CHF), according to a pilot study published in Electrocardiography.
Consecutive patients (n=101; mean age, 83±11 years; 53% men) who were admitted to Sant Andrea Hospital in Italy in 2019 due to decompensated CHF were recruited. Decompensated CHF was defined by the presence of at least 1 symptom of decompensated CHF in patients with a documented history of CHF. Patients were assessed with a standard 5-minute electrocardiogram (ECG) monitored and transmitted via mobile phone to the cloud. From these digitized data, T peak to Te, RR, QT end (QTe), and QT peak (QTp; with mean, SD, and normalized index [N]) were calculated.
Average measures in this cohort were the following: body mass index, 26±5 kg/m2; systolic blood pressure, 125±21 mm Hg; diastolic blood pressure, 69±12 mm Hg; heart rate, 72±14 beats per minute; left ventricular ejection fraction, 44±15%; and median N-terminal pro B-type natriuretic peptide (NT-pro BNP), 2320 pg/mL (interquartile range [IQR], 5459 pg/mL).
Of the 101 patients, 25 died in the hospital. The patients who died had lower systolic (P =.008) and diastolic (P =.012) blood pressure, and higher heart rate (P =.002) and NT-pro BNP levels (P =.001).
Patients who died compared with those who survived also had higher: QTeSD (median, 8; IQR, 4 vs median, 5; IQR, 5, respectively; P =.002), Te mean (mean, 117±30 vs mean, 98±22, respectively; P =.001), TeSD (median, 9; IQR, 3 vs median, 7; IQR, 5, respectively; P =.028), and variance normalized for mean of QTe (median, 0.29 IQR, 0.28 vs median, 0.14; IQR, 0.32, respectively; P =.004).
Te mean was identified as a predictor of in-hospital mortality (odds ratio, 0.09; 95% CI, 0.02-0.35; P =.001) and TeSD was found to positively correlate with NT-pro BNP levels (r, 0.45; P <.001) in a multivariate analysis.
Study limitations include the fact that all electrocardiograph outputs were evaluated by a single clinician whose interpretation of the data may have altered the conclusions drawn from this study.
“[T]he preliminary data of our pilot study suggest that some markers of left ventricular repolarization temporal dispersion were related to poor outcome. Particularly, the TeSD could be used as marker of decompensated CHF and as a surrogate of proBNP in the motoring of severe CHF,” concluded the study authors. “[W]e would like to stress that this ECG signal is easily transmissible by the web and it is virtually inexpensive, therefore easily usable also in telemedicine settings, with a clear costs’ reduction.”
Piccirillo G, Moscucci F, Mariani M V, et al. Hospital mortality in decompensated heart failure. A pilot study. J Electrocardiol. 2020;61:147-152.