ECG-derived spatial QRS-T angle is associated with ICD implantation, mortality and heart failure admissions in patients with LV systolic dysfunction

Abstract

BackgroundIncreased spatial QRS-T angle has been shown to predict appropriate implantable cardioverter defibrilIator (ICD) therapy in patients with left ventricular systolic dysfunction (LVSD). We performed a retrospective cohort study in patients with left ventricular ejection fraction (LVEF) 31–40% to assess the relationship between the spatial QRS-T angle and other advanced ECG (A-ECG) as well as echocardiographic metadata, with all-cause mortality or ICD implantation for secondary prevention.Methods534 patients ≤75 years of age with LVEF 31–40% were identified through an echocardiography reporting database. Digital 12-lead ECGs were retrospectively matched to 295 of these patients, for whom echocardiographic and A-ECG metadata were then generated. Data mining was applied to discover novel ECG and echocardiographic markers of risk. Machine learning was used to develop a model to predict possible outcomes.Results49 patients (17%) had events, defined as either mortality (n = 16) or ICD implantation for secondary prevention (n = 33). 72 parameters (58 A-ECG, 14 echocardiographic) were univariately different (p<0.05) in those with vs. without events. After adjustment for multiplicity, 24 A-ECG parameters and 3 echocardiographic parameters remained different (p<2x10-3). These included the posterior-to-leftward QRS loop ratio from the derived vectorcardiographic horizontal plane (previously associated with pulmonary artery pressure, p = 2x10-6); spatial mean QRS-T angle (134 vs. 112°, p = 1.6x10-4); various repolarisation vectors; and a previously described 5-parameter A-ECG score for LVSD (p = 4x10-6) that also correlated with echocardiographic global longitudinal strain (R2 = - 0.51, P < 0.0001). A spatial QRS-T angle >110° had an adjusted HR of 3.4 (95% CI 1.6 to 7.4) for secondary ICD implantation or all-cause death and adjusted HR of 4.1 (95% CI 1.2 to 13.9) for future heart failure admission. There was a loss of complexity between A-ECG and echocardiographic variables with an increasing degree of disease.ConclusionSpatial QRS-T angle >110° was strongly associated with arrhythmic events and all-cause death. Deep analysis of global ECG and echocardiographic metadata revealed underlying relationships, which otherwise would not have been appreciated. Delivered at scale such techniques may prove useful in clinical decision making in the future.

Prognostic value of frontal QRS-T angle in predicting survival after primary percutaneous coronary revascularization/coronary artery bypass grafting for ST-elevation myocardial infarction

“… 15 Lingman et al demonstrated that QRS-T angle improved prediction of SCD after ACS in addition to traditional cardiac risk factors. 16 Hence, FQRST serves as a useful surrogate for damaged/jeopardized myocardium at risk, thereby, predicting STEMI mortality, as confirmed in our study.…”

Relationship between IGF-I Concentration and Metabolic Profile in Children with Growth Hormone Deficiency: The Influence of Children’s Nutritional State as well as the Ghrelin, Leptin, Adiponectin, and Resistin Serum Concentrations

“…However, the metabolic profile of untreated children with GHD varies in individual reports [4–8]. In Gleeson et al's study [4], the lipid profile was disturbed at baseline in GHD children, while abnormal body composition was only observed in older subjects in late puberty.…”

“…However, the metabolic profile of untreated children with GHD varies in individual reports [4–8]. In Gleeson et al's study [4], the lipid profile was disturbed at baseline in GHD children, while abnormal body composition was only observed in older subjects in late puberty. Also, Capalbo et al reported [5] higher waist to hip ratio, triglycerides, total cholesterol, LDL-cholesterol, and leptin in GHD children compared to controls, whereas no differences in adiponectin concentration were found.…”

“…Thus, adult patients with isolated GH deficiency (GHD) display unfavourable lipid profile with increased fat mass, as well as increased insulin secretion, though with good insulin sensitivity [1, 3]. However, not all children with GHD show a tendency towards metabolic disorders [4–8]. …”

Clinical Application of the Spatial&nbsp;QRS-T Angle for the Prediction of Pulmonary Arterial Hypertension&nbsp;in Patients with Acute Pulmonary Embolism

“…The spatial QRS-T angle has been shown to be associated with sudden cardiac death, ventricular arrhythmia and heart failure. Furthermore, the spatial QRS-T angle has been shown to be increased in patients with various cardiac risk factors, including smoking, diabetes and hypertension [7]. Henkens et al reported that in Wistar rats with experimentally induced-PAH can be detected with increased spatial QRS-T angle [8].…”