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.

Left atrial conduction times and regional velocities in persistent atrial fibrillation patients with and without fibrotic atrial cardiomyopathy.

Despite the progress in understanding left atrial substrate and arrhythmogenesis, only little is known about conduction characteristics in atrial fibrillation patients with various stages of fibrotic atrial cardiomyopathy (FACM). This study evaluates left atrial conduction times and conduction velocities based on high-density voltage and activation maps in sinus rhythm (CARTO®3 V7) of 53 patients with persistent atrial fibrillation (LVEF 60% (55-60 IQR), LAVI 39 ml/m2 (31-47 IQR), LApa 24 ± 6 cm2). Measurements were made in low voltage areas (LVA ≤ 0.5 mV) and normal voltage areas (NVA ≥ 1.5 mV) at the left atrial anterior and posterior walls. Maps of 28 FACM and 25 no FACM patients were analyzed (19 FACM I/II, 9 FACM III/IV, LVA 14 ± 11 cm2). Left atrial conduction time averaged to 110 ± 24 ms but was shown to be prolonged in FACM (119 ms, + 17%) when compared to no FACM patients (101 ms, p = 0.005). This finding was pronounced in high-grade FACM (III/IV) (133 ms, + 31.2%, p = 0.001). In addition, the LVA extension correlated significantly with the left atrial conduction time (r = 0.56, p = 0.002). Conduction velocities were overall slower in LVA than in NVA (0.6 ± 0.3 vs. 1.3 ± 0.5 m/s, -51%, p < 0.001). Anterior conduction appeared slower than posterior, which was significant in NVA (1 vs. 1.4 m/s, -29%, p < 0.001) but not in LVA (0.6 vs. 0.8 m/s, p = 0.096). FACM has a significant influence on left atrial conduction characteristics in patients with persistent atrial fibrillation. Left atrial conduction time prolongs with the grade of FACM and the quantitative expanse of LVA up to 31%. LVAs show a 51% conduction velocity reduction compared to NVA. Moreover, regional conduction velocity differences are present in the left atrium when comparing anterior to posterior walls. Our data may influence individualized ablation strategies.

Standard Transfemoral Transcatheter Aortic Valve Replacement.

The introduction of the transcatheter aortic valve implantation procedure has revolutionized the standards of care in patients with aortic valve pathologies and has significantly increased the quality of the medical treatment provided. The durability and constant technical improvements in the modern transcatheter aortic valve implantation procedure have broadened the indications towards younger patient groups with low-risk profiles. Therefore, transcatheter aortic valve implantation now represents an effective alternative for surgical aortic valve replacement in a large number of cases. Currently, various technical methods for the transcatheter aortic valve implantation procedure are available. The contemporary transcatheter aortic valve implantation procedure focuses on optimization of postoperative results and reduction of complications such as paravalvular leakage and permanent pacemaker implantation. Another goal of transcatheter aortic valve implantation is the achievement of a valid lifetime concept with secure coronary access and conditions for future valve-in-valve interventions.  In this case report, we demonstrate a standard transfemoral transcatheter aortic valve implantation procedure with a self-expandable supra-annular device, one of the most commonly performed methods.

Percutaneous transseptal transcatheter mitral valve-in-valve implantation under endovascular cerebral protection.

Various interventional and minimally invasive surgical approaches are currently available for the treatment of mitral valve pathologies. However, only a few of these options are applicable in patients with previously operated on mitral valves. In this case report, we provide detailed insight into the step-by-step guidance of a percutaneous transseptal transcatheter mitral valve-in-valve implant under cerebral protection in a patient with a deteriorated surgically implanted mitral bioprosthesis.

Transcatheter aortic valve-in-valve implantation under cerebral protection in a patient with a deteriorated 19-mm rapid-deployment bioprosthetic valve.

The introduction of transcatheter aortic valve implantation (TAVI) has dramatically improved the treatment of valvular pathologies in high-risk patients. Additionally, transcatheter aortic valve implantation can be successfully applied in patients with deteriorated surgical bioprosthetic valves, representing an attractive alternative to a redo operation. Valve-in-valve transcatheter aortic valve implantations can be especially challenging in patients with a small-diameter prosthesis and patient-prosthesis mismatch. Bioprosthetic valve fracturing or bioprosthetic valve remodeling can be used to increase the valvular opening area and additionally reduce the transvalvular gradients in patients having an aortic valve implant. In this case report, we provide detailed insight and step-by-step guidance for transcatheter aortic valve-in-valve implantation with bioprosthetic valve fracturing/bioprosthetic valve remodeling under cerebral protection in a patient with a deteriorated 19-mm surgically implanted bioprosthesis.

Transcatheter mitral valve implantation in the ongoing structural heart revolution.

Transcatheter mitral valve implantation (TMVI) has emerged as a less invasive approach potentially surmounting some of the current hurdles associated with transcatheter edge-to-edge repair and high-risk mitral valve surgery. In this review, we aimed to outline the main scenarios in the TMVI field, highlight current and upcoming devices, and describe challenges and clinical results. Finally, we briefly discuss the future perspectives for this emerging field and how TMVI might further advance the field of transcatheter treatments of mitral valve disease.