Effect of preoperative erector spinae muscles mass on postoperative outcomes in patients with left ventricular assist devices

Pectoral muscle mass is not a robust prognostic factor for survival after left ventricular assist device (LVAD) implantation

BACKGROUND

Left ventricular assist devices (LVAD) are an established treatment for end-stage left ventricular heart failure. Parameters are needed to identify the most appropriate patients for LVADs. This study aimed to evaluate pectoral muscle mass and density as prognostic parameters.

METHODS

This single-center study included all patients with LVAD implantation between January 2010 and October 2017 and a preoperative chest CT scan. Pectoral muscle mass was assessed using the Pectoralis Muscle Index (PMI, surface area indexed to height, cm2/m2) and pectoral muscle density by Hounsfield Units (HU). Overall mortality was analyzed with Kaplan-Meier survival analysis and 1-year and 3-year mortality with receiver operating characteristic (ROC) curves and Cox regression models.

RESULTS

57 patients (89.5% male, mean age 57.8 years) were included. 64.9% of patients had end-stage left ventricular failure due to ischemic heart disease and 35.1% due to dilated cardiomyopathy. 49.2% of patients had preoperative INTERMACS profile of 1 or 2 and 33.3% received mechanical circulatory support prior to LVAD implantation. Total mean PMI was 4.7 cm2/m2 (± 1.6), overall HU of the major pectoral muscle was 39.0 (± 14.9) and of the minor pectoral muscle 37.1 (± 16.6). Mean follow-up was 2.8 years (± 0.2). Mortality rates were 37.5% at 1 year and 48.0% at 3 years. Neither PMI nor HU were significantly associated with overall mortality at 1-year or 3-year.

CONCLUSIONS

The results of our study do not confirm the association between higher pectoral muscle mass and better survival after LVAD implantation previously described in the literature.

Artificial intelligence-based analysis of body composition predicts outcome in patients receiving long-term mechanical circulatory support

BACKGROUND

Obesity is a known cardiovascular risk factor and associated with higher postoperative complication rates in patients undergoing cardiac surgery. In heart failure (HF), conflicting evidence in terms of survival has been reported, whereas sarcopenia is associated with poor prognosis. An increasing number of HF patients require left ventricular assist device (LVAD) implantations. The postoperative mortality has improved in recent years but is still relatively high. The impact of body composition on outcome in this population remains unclear. The aim of this investigation was to examine the preoperative computed tomography (CT) body composition as a predictor of the postoperative outcome in advanced HF patients, who receive LVAD implantations.

METHODS

Preoperative CT scans of 137 patients who received LVADs between 2015 and 2020 were retrospectively analysed using an artificial intelligence (AI)-powered automated software tool based on a convolutional neural network, U-net, developed for image segmentation (Visage Version 7.1, Visage Imaging GmbH, Berlin, Germany). Assessment of body composition included visceral and subcutaneous adipose tissue areas (VAT and SAT), psoas and total abdominal muscle areas and sarcopenia (defined by lumbar skeletal muscle indexes). The body composition parameters were correlated with postoperative major complication rates, survival and postoperative 6-min walk distance (6MWD) and quality of life (QoL).

RESULTS

The mean age of patients was 58.21 ± 11.9 years; 122 (89.1%) were male. Most patients had severe HF requiring inotropes (Interagency Registry for Mechanically Assisted Circulatory Support [INTERMACS] profile I-III, 71.9%) secondary to coronary artery diseases or dilated cardiomyopathy (96.4%). Forty-four (32.1%) patients were obese (body mass index ≥ 30 kg/m2 ), 96 (70.1%) were sarcopene and 19 (13.9%) were sarcopene obese. Adipose tissue was associated with a significantly higher risk of postoperative infections (VAT 172.23 cm2 [54.96, 288.32 cm2 ] vs. 124.04 cm2 [56.57, 186.25 cm2 ], P = 0.022) and in-hospital mortality (VAT 168.11 cm2 [134.19, 285.27 cm2 ] vs. 135.42 cm2 [49.44, 227.91 cm2 ], P = 0.033; SAT 227.28 cm2 [139.38, 304.35 cm2 ] vs. 173.81 cm2 [97.65, 254.16 cm2 ], P = 0.009). Obese patients showed no improvement of 6MWD and QoL within 6 months postoperatively (obese: +0.94 ± 161.44 months, P = 0.982; non-obese: +166.90 ± 139.00 months, P < 0.000; obese: +0.088 ± 0.421, P = 0.376; non-obese: +0.199 ± 0.324, P = 0.002, respectively). Sarcopenia did not influence the postoperative outcome and survival within 1 year after LVAD implantation.

CONCLUSIONS

Preoperative AI-based CT body composition identifies patients with poor outcome after LVAD implantation. Greater adipose tissue areas are associated with an increased risk for postoperative infections, in-hospital mortality and impaired 6MWD and QoL within 6 months postoperatively.

The cross-sectional area of erector spinae muscle and the liver-to-spleen ratio are associated with frailty in older patients with diabetes: a cross-sectional study

BACKGROUND

Older patients with diabetes mellitus are more susceptible to frailty. Although some imaging markers of appendicular skeletal muscle mass obtained using dual-energy X-ray absorptiometry or computed tomography (CT) imaging can reflect frailty status, the association between imaging indices obtained by abdominal CT scans and frailty in older inpatients has not been reported.

METHODS

A total of 151 older inpatients with diabetes mellitus (median age, 79 years; men, 42%) who underwent abdominal CT scans close to the admission date were studied to examine the associations between abdominal CT indices and frailty. Two frailty definitions were used: the modified Cardiovascular Health Study (mCHS) criteria and Kihon Checklist (KCL) criteria. Using the imaging analysis software SYNAPSE VINCENT®, we compared the cross-sectional areas (CSA) of four truncal muscles (erector spinae, iliopsoas, rectus abdominis, and abdominal oblique muscles) and the liver-to-spleen ratio (L/S), the ratio of the CT values of the liver and spleen between frail and non-frail patients. The muscle areas that showed the strongest associations with frailty were also investigated in relation to grip strength and walking speed. Finally, multivariate binominal logistic regression analyses were performed to assess the independent associations of CSA of muscle and L/S with the prevalence of frailty.

RESULTS

The prevalence of frailty defined by the mCHS and KCL criteria was 55% and 52%, respectively. The CSA of the erector spinae muscle was most significantly associated with frailty, and was significantly smaller in both sexes of mCHS-defined frail patients and in men with KCL-defined frailty. The CSA of erector spinae muscle was also positively correlated with grip strength and walking speed. In contrast, the L/S was higher in men with KCL-defined frailty. Multivariate logistic regression analyses revealed that the CSA of the erector spinae muscle was independently associated with mCHS-defined frailty in women, and the L/S was associated with KCL-defined frailty in men.

CONCLUSIONS

The CSA of erector spinae muscle and low liver fat content could be indices of frailty in older patients with diabetes.

Cardiac Rehabilitation in Severe Heart Failure Patients with Impella 5.0 Support via the Subclavian Artery Approach Prior to Left Ventricular Assist Device Implantation

Impella 5.0 circulatory support via subclavian artery (SA) access may be a safe approach for patients undergoing cardiac rehabilitation (CR). In this case series, we retrospectively analyzed the demographic characteristics, physical function, and CR data of six patients who underwent Impella 5.0 implantation via the SA prior to left ventricular assist device (LVAD) implantation between October 2013 and June 2021. The median age was 48 years, and one patient was female. Grip strength was maintained or increased in all patients before LVAD implantation (pre-LVAD) compared to after Impella 5.0 implantation. The pre-LVAD knee extension isometric strength (KEIS) was less than 0.46 kgf/kg in two patients and more than 0.46 kgf/kg in three patients (unavailable KEIS data, n = 1). With Impella 5.0 implantation, two patients could ambulate, one could stand, two could sit on the edge of the bed, and one remained in bed. One patient lost consciousness during CR due to decreased Impella flow. There were no other serious adverse events. Impella 5.0 implantation via the SA allows mobilization, including ambulation, prior to LVAD implantation, and CR can be performed relatively safely.

Impact of psoas muscle evaluation on clinical outcomes in patients undergoing left ventricular assist device implantation

AIMS

The measurement of muscle mass reflects the physical components of frailty, which might affect postoperative outcomes in patients undergoing left ventricular assist device (LVAD) implantation. The aim of this study was to investigate the relationship between preoperative skeletal muscle evaluation and clinical outcomes in patients undergoing LVAD implantation.

METHODS

From January 2010 to December 2017, a total of 63 patients were enrolled in this single-centre study. A retrospective analysis of preoperative abdominal computed tomography (CT) for psoas muscle index (PSMI) and Hounsfield-Units of the Psoas Muscle (PSHU) at the level of the mid-L4 vertebra was performed.

RESULTS

Sixty-three patients (male; n = 49, 78%), with a mean age of 58.0 ± 11.8 years, were treated with LVAD due to dilated (32%) or ischemic cardiomyopathy (68%). Among them, 43 patients (68.3%) were categorized in the Interagency Registry for Mechanically Assisted Circulatory Support profile I. The survival rate was 73.0% at 30 days and 44.4% at 1 year. Receiver-operating characteristic (ROC) curve analyses revealed that PSMI was a significant numeric predictor of 1-year mortality (P = 0.04). In contrast, PSHU displayed a significant predictive potential for pericardial effusion (P = 0.03) and respiratory insufficiency (P = 0.01). In addition, comparative ROC curve analysis revealed no significant difference in the predictive potential of PSMI and PSHU.

CONCLUSION

Preoperative PSMI might be a predictor of 1-year mortality in patients undergoing LVAD implantation. In contrast, the PSHU seemed to potentially assume postoperative adverse events in this study. Thus, the evaluation of the preoperative psoas muscle using CT appears to be promising.