The combined risk predictive power of frailty and hypoalbuminemia in free tissue flap reconstruction: A cohort study of 34,571 patients from the NSQIP database

INTRODUCTION

Significant morbidity and mortality are hallmarks of the functional decline seen in physically frail patients. The modified frailty index 5 (mFI-5) represents a risk predictor score that has been validated as a comorbidity-based scale in surgery. Serum albumin levels of <3.5 g/dL (hypoalbuminemia) have also been implicated with poor postoperative outcomes. However, the association between these two parameters remains to be investigated. We aimed to elucidate the interdependence of preoperative albumin levels and frailty, as evaluated by the mFI-5 score, and its reliability to prognosticate postoperative results in free flap reconstruction (FFR).

METHODS

We conducted a multicenter, retrospective cohort study and accessed the ACS National Surgical Quality Improvement Program (ACS-NSQIP) from 2008 to 2021. We identified all adult patients (≥18 years of age) who underwent a FFR. We extracted perioperative data and lab values including albumin. Multivariable linear and logistic regression analyses were performed to identify independent risk predictors. Main outcomes involved mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination within the 30-day postoperative period.

RESULTS

A total of 34,571 patients were included in the study, with an average age of 53.9 years (standard deviation [SD] 12.2) and an average body mass index (BMI) of 28.8 (SD 6.1). Of these patients, 7484 were male (21.6%), whereas 22,363 (64.7%) had no frailty (mFI = 0). Additionally, 9466 patients had a frailty score of 1 (27.4%), 2505 had a score of 2 (7.2%), 226 had a score of 3 (0.7%), and 11 had a score of 4 or higher (0.0%). Albumin levels were available for 16,250 patients (47.0%), and among them, 1334 (8.2%) had hypoalbuminemia. Regression analyses showed that higher mFI scores were independent predictors of any, surgical, and medical complications, as well as increased rates of reoperations, unplanned readmissions, and prolonged hospital stays. Hypoalbuminemia independently predicted any, surgical, and medical complications, and higher mortality, reoperation, and longer hospital stay. When both frailty and albumin levels (mFI-5 and albumin) were considered together, this combined assessment was found to be a more accurate predictor of all major outcomes (any, medical and surgical complications, mortality, and reoperation). Further, our analysis identified a weak negative correlation between serum albumin levels and mFI scores (Spearman R: -.1; p < .0001).

CONCLUSION

In conclusion, this cohort study highlights the association of hypoalbuminemia with adverse postoperative outcomes, including those not directly related to frailty. Simultaneously, higher mFI scores independently predicted outcomes not associated with hypoalbuminemia. Stemming from these findings, we recommend considering both serum albumin levels and frailty in patients receiving FFR. This perioperative algorithm may help provide more individualized planning including multidisciplinary care and pre and posthabilitation.

The individual relationship between atrial fibrillation sources from CARTOFINDER mapping and atrial cardiomyopathy: The catch me if you can trial

BACKGROUND

Targeting individual sources identified during atrial fibrillation (AF) has been used as an ablation strategy with varying results.

OBJECTIVE

Aim of this study was to evaluate the relationship between regions of interest (ROIs) from CARTOFINDER (CF) mapping and atrial cardiomyopathy from late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR).

METHODS

Twenty consecutive patients underwent index catheter ablation for persistent AF (PERS AF). Pre-processed LGE CMR images were merged with the results from CF mapping to visualize harboring regions for focal and rotational activities. Atrial cardiomyopathy was classified based on the four Utah stages.

RESULTS

Procedural success was achieved in all patients (n = 20, 100%). LGE CMR revealed an intermediate amount of 21.41% ± 6.32% for LA fibrosis. ROIs were identified in all patients (mean no ROIs per patient n = 416.45 ± 204.57). A tendency towards a positive correlation between the total amount of atrial cardiomyopathy and the total number of ROIs per patient (regression coefficient, β = 10.86, p = .15) was observed. The degree of fibrosis and the presence of ROIs per segment showed no consistent spatial correlation (posterior: β = 0.36, p-value (p) = .24; anterior: β = -0.08, p = .54; lateral: β = 0.31, p = 39; septal: β = -0.12; p = .66; right PVs: β = 0.34, p = .27; left PVs: β = 0.07, p = .79; LAA: β = -0.91, p = .12). 12 months AF-free survival was 70% (n = 14) after ablation.

CONCLUSION

The presence of ROIs from CF mapping was not directly associated with the extent and location of fibrosis. Further studies evaluating the relationship between focal and rotational activity and atrial cardiomyopathy are mandatory.

General independent censoring in event-driven trials with staggered entry

Randomized clinical trials with time-to-event endpoints are frequently stopped after a prespecified number of events has been observed. This practice leads to dependent data and nonrandom censoring, which can in general not be solved by conditioning on the underlying baseline information. In case of staggered study entry, matters are complicated substantially. The present paper demonstrates that the study design at hand entails general independent censoring in the counting process sense, provided that the analysis is based on study time information only. To illustrate that the filtrations must not use abundant information, we simulated data of event-driven trials and evaluated them by means of Cox regression models with covariates for the calendar times. The Breslow curves of the cumulative baseline hazard showed considerable deviations, which implies that the analysis is disturbed by conditioning on the calendar time variables. A second simulation study further revealed that Efron's classical bootstrap, unlike the (martingale-based) wild bootstrap, may lead to biased results in the given setting, as the assumption of random censoring is violated. This is exemplified by an analysis of data on immunotherapy in patients with advanced, previously treated nonsmall cell lung cancer.

Applications of artificial intelligence/machine learning approaches in cardiovascular medicine: a systematic review with recommendations

Aims

Artificial intelligence (AI) and machine learning (ML) promise vast advances in medicine. The current state of AI/ML applications in cardiovascular medicine is largely unknown. This systematic review aims to close this gap and provides recommendations for future applications.

Methods and results

Pubmed and EMBASE were searched for applied publications using AI/ML approaches in cardiovascular medicine without limitations regarding study design or study population. The PRISMA statement was followed in this review. A total of 215 studies were identified and included in the final analysis. The majority (87%) of methods applied belong to the context of supervised learning. Within this group, tree-based methods were most commonly used, followed by network and regression analyses as well as boosting approaches. Concerning the areas of application, the most common disease context was coronary artery disease followed by heart failure and heart rhythm disorders. Often, different input types such as electronic health records and images were combined in one AI/ML application. Only a minority of publications investigated reproducibility and generalizability or provided a clinical trial registration.

Conclusions

A major finding is that methodology may overlap even with similar data. Since we observed marked variation in quality, reporting of the evaluation and transparency of data and methods urgently need to be improved.

Oral contraceptives moderately effect bone resorption markers and serum-soluble interleukin-6 receptor concentrations

This study investigated the effect of ethinylestradiol(EE2)-containing oral contraceptives on mineral and bone metabolism and on serum soluble-interleukin-6-receptor (sIL-6R) during the menstrual cycle. Twelve women, aged 24.3 +/- 2.9 years, were examined. Blood and 24-hour and fasting urine samples were obtained during one menstrual cycle between cycle day 3-5 (t(1)), cycle day 10-12 (t(2)), cycle day 24-26 (t(3)), and again on day 3-5 of the next cycle (t(4)). EE2 intake was 0 mg at t(1), 30 mg at t(2), 30 mg at t(3) and 0 mg at t(4). Fasting renal phosphorus and calcium excretions were slightly reduced at t(2) and t(3) compared with t(1) and t(4) (P < 0.05-0.001). Moreover, renal excretion of the bone resorption marker C-Teleopeptide was at t(3) reduced by 26% compared with t(1)(P < 0.01) and by 13% compared with t(4)(P > 0.05). Fasting sIL-6R levels were 16.5% lower at t(2) and 12% lower at t(3) than at t(4) (P < 0.01 and P < 0.05). sIL-6R was correlated with total deoxypyridinoline excretion (r = +0.35; P < 0.05) and with fasting renal excretions of calcium (r = +0.36; P < 0.05) and phosphorus (r = +0.29; P < 0.05). In summary, our data suggest that in young women, cyclic monthly oral contraceptive intake is associated with small, but significant variations in bone resorption processes and in serum sIL-6R levels. Results are a further indication that monthly fluctuations of bone resorption in young women are mediated by sex hormones and that osteoclastic activity is stimulated by cytokines in vivo.

31-P MR spectroscopy and MRI of a testicular non-Hodgkin lymphoma recurrence to monitor response to irradiation. A case report

PURPOSE

To monitor the metabolic changes during the radiation treatment of a recurrence of a high malignant non-Hodgkin lymphoma (NHL) of the left testis.

PATIENTS AND METHODS

A 76-year old patients who presented a diffuse centroblastic high malignant NHL recurrence in the left scrotal sac was examined with 31-P magnetic resonance spectroscopy (MRS) and proton magnetic resonance imaging (MRI) before, during and after megavoltage radiotherapy to a total dose of 56 Gy.

RESULTS

The 31-P MRS spectrum of the tumor showed before starting irradiation, intensive phosphomonoester (PME) and phosphodiester (PDE) signals that overlapped the inorganic phosphate (Pi) signal. After 26 Gy irradiation, the Pi peak appeared and revealed an intratumoral pH of 7.08 very close to that in the normal testis (pH of 7.02). After 56 Gy the tumor disappeared and a complete remission was achieved.

CONCLUSIONS

1. 31-P MRS is sensitive to the changes in the tumor metabolic activity after irradiation with a dose of 26 Gy. 2. Pi and PME peaks could be good pathological markers in the steady-state response to irradiation. 3. MRI could confirm the radiation induced tumor regression and the achieved clinical complete remission.

31-P mr spectroscopy of a leg lymphangiosarcoma

In a 64 year old man with a large, low grade lymphangiosarcoma of the right thigh, we correlated the results of in vivo 31-P-magnetic resonance spectroscopy (MRS), proton magnetic resonance imaging (MRI), and digital subtraction (DSA) with the pathologic specimen and histology. The 31-P MRS spectra of the tumor showed well-resolved peaks as follows: intense PCr (phosphocreatine), PDE (phosphodiester) and Pi (inorganic phosphate), and low PME (phosphomonoester). The Pi peak revealed an intratumor pH of 6.96 compared with 7.16 of normal skeletal muscle. The lower PME signal was consistent with low histopathologic mitotic activity of the tumor.