Assessment of left ventricular ejection fraction in critically ill patients at the time of speckle tracking echocardiography: intensivists in training for echocardiography versus experienced operators

Left ventricular global longitudinal strain and acute myocardial injury in patients with sickle cell disease admitted to the intensive care unit for vaso-occlusive crisis

In patients with sickle cell disease (SCD), SCD-related cardiomyopathy may be partly due to repeated ischaemic events related to sickling during vaso-occlusive crises, but few clinical studies support this hypothesis. We evaluated the incidence of acute myocardial ischaemia during vaso-occlusive crises as assessed by the left ventricular global longitudinal strain (LVGLS) and high-sensitive cardiac troponin T (hs-cTnT). We included adult patients with SCD admitted to the intensive care unit (ICU) for vaso-occlusive crisis. We collected hs-cTnT and measured LVGLS with echocardiography at admission (day 1), day 2, day 3 and ICU discharge. Among 55 patients included, considering only the first hospitalization of patients admitted several times, 3 (5%) had elevated hs-cTnT at ≥1 time point of the ICU stay. It was ≤2 times the upper limit of normal in two of these patients. LVGLS was altered at ≥1 time point of the ICU stay in 13 (24%) patients. Both hs-cTnT and LVGLS were abnormal at ≥1 time point of the hospital stay in 2 (4%) patients. Acute myocardial injury as assessed by troponin elevation and LVGLS impairment was a rare event during vaso-occlusive crises.

Echocardiography protocol for early detection of cardiac dysfunction in childhood cancer survivors in the multicenter DCCSS LATER 2 CARD study: Design, feasibility, and reproducibility

BACKGROUND

Cardiotoxicity is a well-known side effect after anthracyclines and chest radiotherapy in childhood cancer survivors (CCS). The DCCSS LATER 2 CARD (cardiology) study includes evaluation of echocardiographic measurements for early identification of CCS at highest risk of developing heart failure. This paper describes the design, feasibility, and reproducibility of the echocardiography protocol.

METHODS

Echocardiograms from CCS and sibling controls were prospectively obtained at the participating centers and centrally analyzed. We describe the image acquisition, measurement protocol, and software-specific considerations for myocardial strain analyses. We report the feasibility of the primary outcomes of systolic and diastolic function, as well as reproducibility analyses in 30 subjects.

RESULTS

We obtained 1,679 echocardiograms. Biplane ejection fraction (LVEF) measurement was feasible in 91% and 96% of CCS and siblings, respectively, global longitudinal strain (GLS) in 80% and 91%, global circumferential strain (GCS) in 86% and 89%, and ≥2 diastolic function parameters in 99% and 100%, right ventricle free wall strain (RVFWS) in 57% and 65%, and left atrial reservoir strain (LASr) in 72% and 79%. Intra-class correlation coefficients for inter-observer variability were 0.85 for LVEF, 0.76 for GLS, 0.70 for GCS, 0.89 for RVFWS and 0.89 for LASr. Intra-class correlation coefficients for intra-observer variability were 0.87 for LVEF, 0.82 for GLS, 0.82 for GCS, 0.85 for RVFWS and 0.79 for LASr.

CONCLUSION

The DCCSS LATER 2 CARD study includes a protocolized echocardiogram, with feasible and reproducible primary outcome measurements. This ensures high-quality outcome data for prevalence estimates and for reliable comparison of cardiac function parameters.

Left ventricular ejection fraction using manual and semi-automated biplane method of discs in very preterm infants

BACKGROUND

Biplane left ventricular ejection fraction (LVEF) is a valuable echocardiographic parameter for assessment of LV systolic pump efficiency in adults and children, but not often reported in preterm infants. The primary aim of this study was to longitudinally measure biplane LVEF in very preterm infants during the neonatal intensive care period. Secondary aim was to compare manual and semi-automatic determination of LVEF for agreement and variability.

METHODS

Stable preterm infants less than 30 weeks gestation were scanned on day 3, day 28, and at 36 weeks postmenstrual age. The LV endocardium was traced manually and semi-automatically using integrated speckle tracking software in apical 4-chamber and apical 3-chamber images to obtain end-diastolic volume and end-systolic volume, and calculate LVEF. Agreement between methods and variability within and between observers was determined using an interclass correlation coefficient (ICC) and Bland-Altman analysis.

RESULTS

Sixty-six preterm infants with a mean birth weight of 1100 (239) g were analyzed. The average manual biplane LVEF was 58 (3)%, 59 (3)%, and 55 (4)% at the three respective time points. Manual LVEF showed good agreement with semi-automatic LVEF (ICC 0.76) with a small bias of -1.5 (3.0)%. Interobserver variability of LVEF improved with semi-automatic tracing of the LV endocardial border (ICC manual 0.68 vs semi-automatic 0.80).

CONCLUSION

Left ventricular systolic pump efficiency in preterm infants remains stable during the neonatal intensive care period. Semi-automatic biplane LVEF has less interobserver variability and can be used interchangeably with manual biplane LVEF.

Evaluation of intensivist basic training in transthoracic echocardiography in the postoperative period of heart surgery

BACKGROUND

Transthoracic echocardiography can significantly change the management of many critical patients, and is being incorporated into many Intensive Care Units (ICU). Very few studies have examined the feasibility and impact of intensivists performing basic transthoracic echocardiography upon the management of critical patients after cardiac surgery. The present study therefore evaluates the quality of acquisition and accuracy of intensivist interpretation of basic transthoracic echocardiograms in the postoperative period of heart surgery.

METHODS

Over an 8-month period we prospectively studied 148 patients within 24h after admission to a university hospital ICU following heart surgery. We performed basic transthoracic echocardiography to evaluate ventricular function, pericardial effusion, hypovolemia and mitral regurgitation. Cohen's Kappa was used to compare transthoracic echocardiograms obtained by intensivists with basic versus advanced training. Concordance on image acquisition and interpretation was evaluated.

RESULTS

We analyzed data of adequate transthoracic echocardiograms in 148 patients (92.5%). Apical four-chamber view and advanced trainees obtained better quality images. Concordance was good for right and left ventricular function (kappa=0.7±0.14 and 0.87±0.05, respectively), and moderate for the remaining parameters. Interpretation concordance between basic and advanced training intensivists was good (kappa=0.73±0.05).

CONCLUSIONS

Intensivists with basic training in echocardiography are capable of performing and interpreting echocardiograms in most patients during the postoperative period of heart surgery.