Diagnostic and Outcome Prediction Value of Transthoracic Impedance Cardiography in Heart Failure Patients During Heart Failure Flare-Ups

Abstract

BackgroundThis study aimed at evaluating the diagnostic and outcome prediction value of transthoracic impedance cardiography (ICG) in heart failure (HF) patients admitted for in-hospital treatment due to flare-ups of their condition.Material/MethodsIn total, 120 patients of intensive care units who were admitted due to HF flare-ups were involved to the study. The findings of ICG were compared to data obtained by other methods used for diagnosing HF.ResultsStatistically significant (p<0.001) results were obtained when evaluating differences in ICG data between admission and discharge from the intensive care unit. In addition, a correlation was detected between brain natriuretic peptide (BNP) and thoracic fluid content index (r=0.4, p<0.001). Differences in ICG values, and BNP data emerged after the participants were grouped according to NYHA classes (p<0.05). The evaluation of lethal outcome during 6 months after the discharge yielded statistically significant results: BNP ≥350 pg/mL (Odds Ratio (OR) 4.4), thoracic fluid content ≥34 1/kOhm (OR 4.3), and systolic time ratio ≥0.55 (OR 2.9), p<0.05.ConclusionsICG data might be applied for the diagnosis and prognosis of HF, although the links between ICG and HF need further evaluation.

Effects of early phase 1 cardiac rehabilitation on cardiac function evaluated by impedance cardiography in patients with coronary heart disease and acute heart failure

“…Emerging studies have demonstrated the correlation of STR and risk of death in patients with HF. Sadauskas et al reported that STR ≥ 0.55 is an indicator of higher risk to death in 6 months in patients with recurrent HF (OR = 0.29) ( 37 ). Moreover, in PREDICT trial, a multicenter trial including 2,316 patients, the hemodynamic parameters including STR were identified as a predictor of short-term clinical events, such as HF recurrent decompensation ( 21 ).…”

Single-Center Study in Lithuania to Evaluate the Role of Transthoracic Impedance Cardiography in the Diagnosis and Outcome Evaluation of 301 Patients with Chronic Heart Failure Exacerbation

“…ICG parameters were recorded immediately after TTE, using a Niccomo™ transthoracic ICG monitor (Medis Medizinische Messtechnik GmbH, Ilmenau, Germany) [20] and on the last day of patient's in-hospital treatment, except if there was a death during the hospitalization period. All ICG parameters were recorded, although we only evaluated the main parameters, suitable for the diagnosis and prognosis of HF: systolic index, TFC, cardiac output, TFCI, systolic time ratio, left cardiac work, and left cardiac work index [9][10][11]17].…”

“…However, other researchers found only a modest correlation between invasively measured cardiac output and cardiac output measured during ICG (r=0.4 to 0.6 on serial measurements) [ 13 ]. In our previous research, we also found only a weak correlation between BNP and cardiac output measured during ICG (r=−0.23, P =0.012) [ 11 ]. ICG parameters have also been extensively researched as possible prognostic indicators in patients with HF.…”

“…For example, Galas et al [ 9 ] showed that thoracic fluid content (TFC), the marker of chest congestion, had a moderately strong positive correlation with NT-proBNP (r=0.46, P =0.000001), while the systolic index showed a weak negative correlation with NT-proBNP (r=−0.22, P =0.036). In our previous studies conducted with hospitalized HF patients, we also found that the TFC and thoracic fluid content index (TFCI) had a moderately strong correlation with serum brain natriuretic peptide (BNP) concentration, with correlation coefficients of 0.32 ( P <0.001) and 0.425 ( P =0.001), respectively [ 10 , 11 ]. Other researchers compared TFC applicability in determining lung congestion, comparing B-lines acquired during lung ultrasound with TFC, and found that TFC was a reliable diagnostic method, with a correlation index of 0.58 ( P <0.0001).…”

A Retrospective Study of Hemodynamic Changes in Patients After Off-Pump Coronary Artery Bypass Graft Surgery Using Impedance Cardiography

“…For example, when monitoring patients with heart failure, ICG data that included cardiac output (CO), the systolic time ratio (STR) were found to correlate with the left ventricular ejection fraction (LVEF) [11]. A significant association between ICG data and CO have also been shown [12]. previously published studies have shown a significant correlation between LVEF and STR [13,14].…”