Prognostic value of cardiovascular magnetic resonance left ventricular volumetry and geometry in patients receiving an implantable cardioverter defibrillator

Meta-Analysis of Normal Reference Values for Right and Left Ventricular Quantification by Cardiovascular Magnetic Resonance

BACKGROUND

Cardiovascular magnetic resonance (CMR) reference values are relied upon to accurately diagnose left ventricular (LV) and right ventricular (RV) pathologies. To date, reference values have been derived from modest sample sizes with limited patient diversity and attention to 1 but not both commonly used tracing techniques for papillary muscles and trabeculations. We sought to overcome these limitations by meta-analyzing normal reference values for CMR parameters stemming from multiple countries, vendors, analysts, and patient populations.

METHODS

We comprehensively extracted published and unpublished data from studies reporting CMR parameters in healthy adults. A steady-state free-precession short-axis stack at 1.5T or 3T was used to trace either counting the papillary muscles and trabeculations in the LV volume or mass. We used a novel Bayesian hierarchical meta-analysis model to derive the pooled lower and upper reference values for each CMR parameter. Our model accounted for the expected differences between tracing techniques by including informative prior distributions from a large external data set.

RESULTS

A total of 254 studies from 25 different countries were systematically reviewed, representing 12 812 healthy adults, of which 52 were meta-analyzed. For LV parameters counting papillary muscles and trabeculations in the LV volume, pooled normative reference ranges in men and women, respectively, were as follows: LV ejection fraction of 52% to 73% and 54% to 75%, LV end-diastolic volume index of 60 to 109 and 56 to 96 mL/m2, LV end-systolic volume index of 18 to 45 and 16 to 38 mL/m2, and LV mass index of 41 to 76 and 33 to 57 g/m2. For LV parameters counting papillary muscles and trabeculations in the LV mass, pooled normative reference ranges in men and women, respectively, were as follows: LV ejection fraction of 57% to 74% and 57% to 75%, LV end-diastolic volume index of 60 to 97 and 55 to 88 mL/m2, LV end-systolic volume index of 18 to 37 and 15 to 34 mL/m2, and LV mass index of 50 to 83 and 38 to 65 g/m2. For RV parameters, pooled normative reference ranges in men and women, respectively, were as follows: RV ejection fraction of 47% to 68% and 49% to 71%, RV end-diastolic volume index of 64 to 115 and 57 to 99 mL/m2, RV end-systolic volume index of 23 to 52 and 18 to 42 mL/m2, and RV mass index of 14 to 29 and 13 to 25 g/m2.

CONCLUSIONS

Our Bayesian hierarchical meta-analysis provides normative reference values for CMR parameters of LV and RV size, systolic function, and mass, encompassing both tracing techniques across a diverse multinational sample of healthy men and women.

Pediatric Cardiac Magnetic Resonance Reference Values for Biventricular Volumes Derived From Different Contouring Techniques

BACKGROUND

Measurement of ventricular volumes and function using MRI is an important tool in pediatric congenital heart disease. However, normal values for children are sparce and analysis methods are inconsistent.

PURPOSE

To propose biventricular reference values in children for two MRI postprocessing (contouring) techniques.

STUDY TYPE

Retrospective.

SUBJECTS

A total of 154 children from two institutions (13.9 ± 2.8 years; 101 male) that were referred for a clinical MRI study.

FIELD STRENGTH/SEQUENCE

1.5 T; balanced steady-state free precession (bSSFP) sequence.

ASSESSMENT

Left ventricular (LV) and right ventricular (RV) end-diastolic and end-systolic volumes (LVEDV, LVESV, RVEDV, RVESV) and end-diastolic and end-systolic myocardial mass (LVEDMM, LVESMM, RVEDMM, RVESMM) were measured from short-axis images using two contouring techniques: 1) papillary muscles, trabeculations and the moderator band were included in the ventricular blood volume and excluded from the myocardial mass, 2) papillary muscles, trabeculations and the moderator band were excluded from the ventricular volume and included in the ventricular mass.

STATISTICAL TESTS

Univariable and multivariable linear regression models were used to evaluate relationships between sex, weight, height, body surface area (BSA) and age and volumetric results. Reference graphs and tables were created with the LMS-method. Contouring techniques were compared by intraclass correlation, regression analysis and Bland-Altman plots. A P value < 0.05 was considered statistically significant.

RESULTS

Height and BSA were significantly associated with LVESV (method 1) and with LVEDV and RVEDV (method 2). LVESV (method 2), RVESV (both methods), RVEDV (method 1), and LVEDMM and RVEDMM (both methods), showed significant associations with height and weight. LVSV and RVSV (both methods) were significantly associated with BSA and weight. RVESV (method 1) was significantly associated with age. Gender showed significant associations for all parameters.

DATA CONCLUSION

The proposed pediatric reference values can be used in the diagnosis and follow-up of congenital or acquired heart disease and for research purposes.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Diabetes mellitus is associated with more adverse non-hemodynamic left ventricular remodeling and less recovery in patients with primary aldosteronism

The elevated aldosterone in primary aldosteronism (PA) is associated with increased insulin resistance and prevalence of diabetes mellitus (DM). Both aldosterone excess and DM lead to left ventricular (LV) pathological remodeling. In this study, we investigated the impact of DM on LV non-hemodynamic remodeling in patients with PA. We enrolled 665 PA patients, of whom 112 had DM and 553 did not. Clinical, biochemical, and echocardiographic data were analyzed at baseline and 1 year after adrenalectomy. LV non-hemodynamic remodeling was represented by inappropriate excess left ventricular mass index (ieLVMI), which was defined as the difference between left ventricular mass index (LVMI) and predicted left ventricular mass index (pLVMI). Propensity score matching (PSM) was used with age, sex, systolic, and diastolic blood pressure to adjust for baseline variables. After PSM, the patient characteristics were balanced between the DM and non-DM groups, except for fasting glucose, HbA1c, and lipid profile. A total of 111 DM and 419 non-DM patients were selected for further analysis. Compared to the non-DM group, the DM group had significantly higher ieLVMI and LVMI. After multivariable linear regression analysis, the presence of DM remained a significant predictor of increased ieLVMI. After adrenalectomy, ieLVMI decreased significantly in the non-DM group but not in DM group. The presence of DM in PA patients was associated with more prominent non-hemodynamic LV remodeling and less recovery after adrenalectomy.