Mid-diastolic left ventricular volume and mass: Normal values for coronary computed tomography angiography

Identifying left ventricular dysfunction using prospective electrocardiogram-triggered coronary computed tomography angiography

PURPOSE

Coronary computed tomography angiography (CCTA) is an important non-invasive tool for the assessment of coronary artery disease and the delivery of information incremental to coronary anatomy. CCTA measured left ventricular (LV) mid-diastolic volume (LVMDV) and LV mass (LVMass) have important prognostic information but the utility of prospectively ECG-triggered CCTA to predict reduced left ventricular ejection fraction (LVEF) is unknown. The objective of this study was to determine if indexed LVMDV (LVMDVi) and the LVMDV:LVMass ratio on CCTA can identify patients with reduced LVEF.

MATERIALS/METHODS

8179 patients with prospectively ECG-triggered CCTA between November 2014 and December 2019 were reviewed. A subset derivation cohort of 4352 healthy patients was used to define normal LVMDVi and LVMDV:LVMass. Sex-specific thresholds were tested in a validation cohort of 1783 patients, excluded from the derivation cohort, with cardiac disease and known LVEF. The operating characteristics for 1 SD above the mean were tested for the identification of abnormal LVEF, LVEF≤35 ​% and ≤30 ​%.

RESULTS

The derivation cohort had a mean LVMDVi of 61.0 ​± ​13.7 ​mL/m2 and LVMDV:LVMass of 1.11 ​± ​0.24 ​mL/g. LVMDVi and LVMDV:LVMass were both higher in patients with reduced LVEF than those with normal LVEF (98.8 ​± ​40.8 ​mL/m2 vs. 63.3 ​± ​19.7 ​mL/m2, p ​< ​0.001, and 1.32 ​± ​0.44 ​mL/g vs. 1.05 ​± ​0.28 ​mL/g, p ​< ​0.001). Both mean LVMDVi and LVMDV:LVMass increased with the severity of LVEF reduction. Sex-specific LVMDVi thresholds were 79 ​% and 80 ​% specific for identifying abnormal LVEF in females (LVMDVi ​≥ ​69.9 ​mL/m2) and males (LVMDVi ​≥ ​78.8 ​mL/m2), respectively. LVMDV:LVMass thresholds had high specificity (87 ​%) in both females (LVMDVi:LVMass ​≥ ​1.39 ​mL/g) and males (LVMDVi:LVMass ​≥ ​1.30 ​mL/g).

CONCLUSION

Our study provides reference thresholds for LVMDVi and LVMDV:LVMass on prospectively ECG-triggered CCTA, which may identify patients who require further LV function assessment.

The estimation of left ventricular function using prospective ECG-triggered coronary CT angiography

BACKGROUND

Coronary computed tomography angiography (CCTA) is vital for diagnosing coronary artery disease; however, prospective ECG-triggered acquisition, minimizing radiation exposure, limits left ventricular (LV) ejection fraction (EF) evaluation. We aimed to assess the feasibility and utility of LVEF100msec, a new index for estimating LV function using volumetric changes during 100 msec within systole.

METHODS

This retrospective study analyzed patients who underwent prospective ECG-triggered CCTA with systolic acquisition between January 2015 and June 2022. The LVEF100msec was calculated using the maximum and minimum LV volumes among the three phases (300, 350, and 400 msec post-QRS) and expressed as a percentage. Patients were classified into normal, mild-moderately reduced, or severely reduced LV function categories based on the reference test. The LVEF100msec was compared among groups, and the optimal cutoff value of LVEF100msec for predicting severe LV dysfunction was investigated.

RESULTS

The study included 271 patients (median age ​= ​58 years, 52% male). LVEF was normal in 188 (69.4%), mild-moderately reduced in 57 (21.0%), and severely reduced in 26 (9.6%) patients. Median LVEF100msec value was 9.0 (6.7-12.6) for normal LV function, 4.7 (3.1-8.8) for mild-moderately reduced, and 2.9 (1.5-3.8) for severely reduced LV function. LVEF100msec values significantly differed among categories (p ​< ​0.001). The optimal LVEF100msec cutoff for severe LV dysfunction was 4.3%, with an AUC of 0.924, sensitivity of 88%, and specificity of 89%.

CONCLUSION

The LVEF100msec may serve as a valuable indicator of severe LV dysfunction.

Cyclothymic affective temperament is independently associated with left ventricular hypertrophy in chronic hypertensive patients

OBJECTIVE

Affective temperaments (depressive, anxious, irritable, hyperthymic, and cyclothymic) are regarded as the stable core of personality and when present in their dominant form, are considered subclinical manifestations and high-risk states for various affective disorders. Furthermore, cumulating evidence supports their relationship with cardiovascular diseases. Our aim was to assess the association between affective temperaments and left ventricular hypertrophy (LVH) in chronic hypertensive patients.

METHODS

In the present cross-sectional study, 296 patients referred to coronary computed tomography angiography (CCTA) due to suspected coronary artery disease were analyzed. All patients completed the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A). Left ventricular mass was quantified by CCTA and indexed to the body surface area (LVMi). Logistic regression analysis was used to identify predictors of LVH (men: ≥67.2 g/m² and women: ≥54.7 g/m²).

RESULTS

Among our patient cohort (mean age: 59.4 ± 10.6, 44.9% female), the median LVM and LVMi were 115.5 [88.4-140.7] g and 58.4 [47.4-64.2] g/m², respectively. Elevated BMI (OR = 1.04 CI: 1.01-1.10, p = 0.04) and cyclothymic affective temperament scores (OR = 1.06 CI: 1.00-1.12, p = 0.04) significantly increased the odds of LVH in multivariate logistic regression analysis.

CONCLUSION

Assessment of affective temperaments may allow for the identification of chronic hypertensive patients with elevated risk for LVH as a potential target for earlier primary intervention.

Circulating Levels of IL-13, TGF-β1, and Periostin as Potential Biomarker for Coronary Artery Disease with Acute Heart Failure

Objective

Coronary artery disease (CAD) and associated comorbidities such as heart failure (HF) remain the leading cause of morbidity and mortality worldwide, attributed to, at least partially, the lack of biomarkers for efficient disease diagnosis. The study intended to explore potential biomarkers for predicting the presence of HF in CAD patients.

Methods

According to the presence of HF, 83 CAD patients with HF were assigned to the AHF group and 52 CAD patients without HF to the CAD group. Additionally, healthy controls (n = 52) were those who had received physical examinations at the same period. The serum levels of IL-13, TGF-β1, and periostin were detected by the enzyme-linked immunosorbent assay (ELISA). Left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD), left ventricle-end diastolic volume (LVEDV), and left ventricular mass index (LVMI) were detected 3 times by color Doppler ultrasound. The predictive values of IL-13, TGF-β1, and periostin methods were compared by receiver-operating characteristic (ROC) analysis and the area under the curve (AUC).

Results

Increased levels of IL-13, TGF-β1, and periostin were noted in the AHF group than in the control and CAD groups (p < 0.001); the CAD group showed higher levels of IL-13, TGF-β1, and periostin than the control group (p < 0.001). Based on the NYHA classification, there were 33 cases with grade II, 28 cases with grade III, and 22 cases with grade IV among 83 CAD patients with HF. It was found that the serum levels of IL-13, TGF-β1, and periostin were higher in the AHF-IV group than in the AHF-III and AHF-II groups (p < 0.001); these levels were also higher in the AHF-III group than in the AHF-II group (p < 0.001). The periostin level was positively correlated with the levels of IL-13 (r = 0.458) and TGF-β1 (r = 0.569) in CAD patients with AHF. Besides, the serum levels of periostin (r = -0.425), IL-13 (r = -0.341), and TGF-β1 (r = -0.435) were negatively correlated with the LVEF of CAD patients with AHF, respectively. When IL-13, TGF-β1, and periostin levels were used to predict the presence of AHF in CAD patients in combination, the sensitivity and specificity were 75.9% and 90.38%, respectively, with the AUC of 0.906 (95% CI: 0.912–0.996).

Conclusion

These data reveal that IL-13, TGF-β1, and periostin levels might be associated with the occurrence of AHF in CAD patients and their combination shows the predictive value for the presence of AHF in CAD patients.

Are Training Programs Ready for the Rapid Adoption of CCTA?: CBME in CCTA

OBJECTIVES

This study sought to assess training volumes and its relationship to learning and identify potential new thresholds for determining expertise.

BACKGROUND

Competency-based medical education (CBME) is being rapidly adopted and therefore training programs will need to adapt and identify new and novel methods of defining, measuring, and assessing clinical skills.

METHODS

Consecutive cardiac computed tomography (CT) studies were interpreted independently by trainees and expert readers, and their interpretations (Agatston score, coronary artery disease severity, and Coronary Artery Disease Reporting and Data System) were collected. Kappa agreements were measured between trainees and experts for every 50 consecutive cases. Agreements between trainees and experts were tracked and compared with the agreement between expert readers.

RESULTS

A total of 36 trainees interpreted 14,432 cardiac CT studies. Agreement between trainees and experts increased with CT case volumes, but trainees learned at different rates. Using a threshold for expertise, skill of measuring coronary calcification was achieved within 50 cases, but expertise for coronary CT angiography appeared to require a mean case volume of 750, comprising 400 abnormal cases.

CONCLUSIONS

Current volume-based training guidelines may be insufficient and higher case volumes may be required. We demonstrate that tracking cardiac CT learners is feasible and that CBME could be incorporated into CT training programs.

Prognostic implications of cardiac damage classification based on computed tomography in severe aortic stenosis

AIMS

An echocardiographic staging system of severe aortic stenosis (AS) based on additional extra-valvular cardiac damage has been associated with prognosis after transcatheter aortic valve implantation (TAVI). Multidetector row computed tomography (MDCT) is key in the evaluation of AS patients undergoing TAVI and can potentially detect extra-valvular cardiac damage. This study aimed at evaluating the prognostic implications of an MDCT staging system of severe AS in patients undergoing TAVI.

METHODS AND RESULTS

A total of 405 patients (80 ± 7 years, 52% men) who underwent full-beat MDCT prior to TAVI were included. The extent of cardiac damage was assessed by MDCT and classified in five categories; Stage 0 (no cardiac damage), Stage 1 (left ventricular damage), Stage 2 (left atrium and mitral valve damage), Stage 3 (right atrial damage), and Stage 4 (right ventricular damage). Twenty-seven (7%) patients were stratified as Stage 0, 96 (24%) as Stage 1, 152 (38%) as Stage 2, 78 (19%) as Stage 3, and 52 (13%) as Stage 4. During a median follow-up of 3.7 (IQR 1.7-5.5) years, 150 (37%) died. On multivariable Cox regression analysis, cardiac damage Stage 3 (HR vs. Stage 0: 4.496, P = 0.039) and Stage 4 (HR vs. Stage 0: 5.565, P = 0.020) were independently associated with all-cause mortality.

CONCLUSION

The MDCT-based staging system of cardiac damage in severe AS effectively identifies the patients who are at higher risk of death after TAVI.

Impact of pericoronary adipose tissue inflammation on left ventricular hypertrophy and regional physiological indices in stable coronary artery disease patients with preserved systolic function

Systemic low-grade inflammation has been shown to be associated with left ventricular hypertrophy (LVH). However, the relationship between pericoronary adipose tissue attenuation (PCATA) and both LVH and regional physiological indices remains unknown. This study aimed to evaluate the association of PCATA with LVH and regional physiological indices in stable coronary artery disease (CAD) patients with preserved systolic function. A total of 114 CAD patients who underwent coronary CT angiography (CTA) and invasive physiological tests showing ischemia due to a single de novo lesion were included in the study. On proximal 40-mm segments of all three major coronary vessels on CTA, PCATA was assessed by the crude analysis of the mean CT attenuation value [- 190 to - 30 Hounsfield units [HU)] and the culprit vessel PCATA was used for the analysis. Regional physiological indices were invasively obtained by pressure-temperature sensor-tipped wire. The patients were divided into three groups by culprit vessel PCATA tertiles, and clinical, CTA-derived, and physiological indices were compared. Univariable and multivariable analyses were further performed to determine the predictors of LVH. Angiographic stenosis severity, culprit lesion locations, culprit vessel fractional flow reserve, coronary flow reserve, index of microcirculatory resistance, total and target vessel coronary calcium score, and biomarkers including high-sensitivity C-reactive protein were not different among the groups. The left ventricular (LV) mass, LV mass index (LVMI), and LV mass at risk were all significantly different in the three groups with the greatest values in the highest tertile group (all, P < 0.05). On multivariable analysis, male gender, NT-proBNP, and PCATA were independent predictors of LVMI. Culprit vessel PCATA was significantly associated with LVMI, but not with regional physiology in CAD patients with functionally significant lesions and preserved systolic function. Our results may offer insight into the pathophysiological mechanisms linking pericoronary inflammation and LVH to worse prognosis.

Determining Early Remodeling Patterns in Diabetes and Hypertension Using Cardiac Computed Tomography: The Feasibility of Assessing Early LV Geometric Changes

BACKGROUND

There is conflicting data on early left ventricle (LV) remodeling in diabetes mellitus (DM) and hypertension (HTN). This study examines the feasibility of cardiac computed tomography angiography (CCTA) to detect early LV geometric changes in patients with DM and HTN.

METHODS

Consecutive patients (n = 5,992) who underwent prospective electrocardiography (ECG)-triggered (mid-diastolic) CCTA were screened. Patients with known structural heart disease or known LV dysfunction were excluded. Left ventricular mass (LVM), left ventricular mid-diastolic volume (LVMDV), and LV concentricity (LVM/LVMDV) were measured and indexed to body surface area.

RESULTS

A total of 4,283 patients were analyzed (mean age 57 ± 10.69 years, female 46.7%). DM, HTN, and HTN + DM were present in 4.1%, 35.8% and 10.6% of patients, respectively. Compared to normal patients, HTN and HTN + DM patients had increased LVM indexed to body surface area (LVMi) (56.87 ± 17.24, 59.26 ± 13.62, and 58.56 ± 13.09, respectively; P < 0.05). There was no difference in LVMi between normal subjects and patients with DM (56.39 ± 11.50, P = 0.617).Concentricity indices were higher in patient with HTN (1.0456 ± 0.417; P < 0.001), DM (1.109 ± 0.638; P = 0.004), and HTN + DM (1.083 ± 0.311, P < 0.001) than normal individuals (0.9671 ± 0.361). There was no overlap of the 95% confidence intervals in the composite of concentricity indices and LVMi between the different groups.

CONCLUSIONS

CCTA measures of LVM and concentricity index may discriminate patients with HTN and DM before overt structural heart disease.

Mechanisms of Arrhythmogenicity in Hypertrophic Cardiomyopathy: Insight From Non-invasive Electrocardiographic Imaging

Background

Mechanisms of arrhythmogenicity in hypertrophic cardiomyopathy (HCM) are not well understood.

Objective

To characterize an electrophysiological substrate of HCM in comparison to ischemic cardiomyopathy (ICM), or healthy individuals.

Methods

We conducted a prospective case-control study. The study enrolled HCM patients at high risk for ventricular tachyarrhythmia (VT) [n = 10; age 61 ± 9 years; left ventricular ejection fraction (LVEF) 60 ± 9%], and three comparison groups: healthy individuals (n = 10; age 28 ± 6 years; LVEF > 70%), ICM patients with LV hypertrophy (LVH) and known VT (n = 10; age 64 ± 9 years; LVEF 31 ± 15%), and ICM patients with LVH and no known VT (n = 10; age 70 ± 7 years; LVEF 46 ± 16%). All participants underwent 12-lead ECG, cardiac CT or MRI, and 128-electrode body surface mapping (BioSemi ActiveTwo, Netherlands). Non-invasive voltage and activation maps were reconstructed using the open-source SCIRun (University of Utah) inverse problem-solving environment.

Results

In the epicardial basal anterior segment, HCM patients had the greatest ventricular activation dispersion [16.4 ± 5.5 vs. 13.1 ± 2.7 (ICM with VT) vs. 13.8 ± 4.3 (ICM no VT) vs. 8.1 ± 2.4 ms (Healthy); P = 0.0007], the largest unipolar voltage [1094 ± 211 vs. 934 ± 189 (ICM with VT) vs. 898 ± 358 (ICM no VT) vs. 842 ± 90 μV (Healthy); P = 0.023], and the greatest voltage dispersion [median (interquartile range) 215 (161–281) vs. 189 (143–208) (ICM with VT) vs. 158 (109–236) (ICM no VT) vs. 110 (106–168) μV (Healthy); P = 0.041]. Differences were also observed in other endo-and epicardial basal and apical segments.

Conclusion

HCM is characterized by a greater activation dispersion in basal segments, a larger voltage, and a larger voltage dispersion through LV.

Clinical Trial Registration

www.clinicaltrials.gov Unique identifier: NCT02806479.

Left Ventricular Mid-Diastolic Wall Thickness: Normal Values for Coronary CT Angiography

Purpose

To generate normal reference values for left ventricular mid-diastolic wall thickness (LV-MDWT) measured by using CT angiography.

Materials and Methods

LV-MDWT was measured in 2383 consecutive patients, without structural heart disease, undergoing prospective electrocardiographically (ECG) triggered mid-diastolic coronary CT angiography. LV-MDWT was manually measured on automatically segmented short-axis images according to the American Heart Association's 17-segment model. Commercially available automatic software was used to calculate the left ventricular (LV) mass.

Results

Among the 2383 patients, average LV-MDWT was 7.24 mm ± 1.86 (standard deviation [SD]), with the basal anteroseptal segment being the thickest wall (8.71 mm ± 2.19) and the apical inferior segment being the thinnest wall (5.9 mm ± 1.58; P < .001). Over all LV segments, the maximum upper limit, as defined as 2 SD above the mean, was 13.6 mm for men (LV1) and 11.2 mm for women. For men, only the basal anterior segment was above 13 mm. There was a significant difference in average LV-MDWT between women and men with 6.47 mm ± 1.07 and 7.90 mm ± 1.24, respectively (P < .001). Significant differences in LV-MDWT were found in the subgroups aged less than 65 years and greater than or equal to 65 years (P < .001). There was a strong correlation between LV-MDWT and LV mass (P < .001).

Conclusion

Normal sex- and age-specific reference ranges for LV-MDWT in prospective ECG-triggered mid-diastolic coronary CT angiography have been provided. These benchmarks may expand the diagnostic and prognostic roles of CT angiography, beyond its role in the identification of coronary artery disease.© RSNA, 2019.

Clinical determinants of plasma cardiac biomarkers in patients with stable chest pain

OBJECTIVE

Troponin and B-type natriuretic peptide (BNP) concentrations are associated with cardiovascular risk in stable patients. Understanding their determinants and identifying modifiable clinical targets may improve outcomes. We aimed to establish clinical and cardiac determinants of these biomarkers.

METHODS

This was a prespecified substudy from the randomised Scottish Computed Tomography of the Heart trial, which enrolled patients 18-75 years with suspected stable angina between 2010 and 2014 (NCT01149590). We included patients from six centres in whom high-sensitivity troponin I and BNP were measured (Singulex Erenna). Patients with troponin >99th centile upper reference limit (10.2 ng/L) or BNP ≥400 ng/L were excluded to avoid inclusion of patients with myocardial injury or heart failure. Multivariable linear regression models were constructed with troponin and BNP as dependent variables.

RESULTS

In total, 885 patients were included; 881 (99%) and 847 (96%) had troponin and BNP concentrations above the limit of detection, respectively. Participants had a slight male preponderance (n=513; 56.1%), and the median age was 59.0 (IQR 51.0-65.0) years. The median troponin and BNP concentrations were 1.4 (IQR 0.90-2.1) ng/L and 29.1 (IQR 14.0-54.0) ng/L, respectively. Age and atherosclerotic burden were independent predictors of both biomarkers. Male sex, left ventricular mass and systolic blood pressure were independent predictors of increased troponin. In contrast, female sex and left ventricular volume were independent predictors of increased BNP.

CONCLUSIONS

Troponin and BNP are associated with coronary atherosclerosis but have important sex differences and distinct and contrasting associations with CT-determined left ventricular mass and volume.

CLINICAL TRIAL REGISTRATION

NCT01149590; Post-results.