Venous congestion has emerged as an important cause of renal dysfunction in patients with cardiorenal syndrome. However, only limited progress has been made in differentiating this haemodynamic phenotype of renal dysfunction, because of a significant overlap with pre-existing renal impairment due to long-term hypertension, diabetes, and renovascular disease. We propose congestive nephropathy (CN) as this neglected clinical entity. CN is a potentially reversible subtype of renal dysfunction associated with declining renal venous outflow and progressively increasing renal interstitial pressure. Venous congestion may lead to a vicious cycle of hormonal activation, increased intra-abdominal pressure, excessive renal tubular sodium reabsorption, and volume overload, leading to further right ventricular (RV) stress. Ultimately, renal replacement therapy may be required to relieve diuretic-resistant congestion. Effective decongestion could preserve or improve renal function. Congestive acute kidney injury may not be associated with cellular damage, and complete renal function restoration may be a confirmatory diagnostic criterion. In contrast, a persistently low renal perfusion pressure might induce renal dysfunction and histopathological lesions with time. Thus, urinary markers may differ. CN is mostly seen in biventricular heart failure but may also occur secondary to pulmonary arterial hypertension and elevated intra-abdominal pressure. An increase in central venous pressure to >6 mmHg is associated with a steep decrease in glomerular filtration rate. However, the central venous pressure range that can provide an optimal balance of RV and renal function remains to be determined. We propose criteria to identify cardiorenal syndrome subgroups likely to benefit from decongestive or pulmonary hypertension-specific therapies and suggest areas for future research.

Background: Persistent congestion with deteriorating renal function is an important cause of adverse outcomes in heart failure. We aimed to characterize new approaches to evaluate renal congestion using Doppler ultrasonography. Methods and Results: We enrolled 205 patients with suspected or prediagnosed pulmonary hypertension ( PH ) undergoing right heart catheterization. Patients underwent renal Doppler ultrasonography and assessment of invasive cardiopulmonary hemodynamics, echocardiography, renal function, intra‐abdominal pressure, and neurohormones and hydration status. Four spectral Doppler intrarenal venous flow patterns and a novel renal venous stasis index ( RVSI ) were defined. We evaluated PH ‐related morbidity using the Cox proportional hazards model for the composite end point of PH progression (hospitalization for worsening PH , lung transplantation, or PH ‐specific therapy escalation) and all‐cause mortality for 1‐year after discharge. The prognostic utility of RVSI and intrarenal venous flow patterns was compared using receiver operating characteristic curves. RVSI increased in a graded fashion across increasing severity of intrarenal venous flow patterns ( P <0.0001) and was significantly associated with right heart and renal function, intra‐abdominal pressure, and neurohormonal and hydration status. During follow‐up, the morbidity/mortality end point occurred in 91 patients and was independently predicted by RVSI ( RVSI in the third tertile versus referent: hazard ratio: 4.72 [95% CI, 2.10–10.59; P <0.0001]). Receiver operating characteristic curves suggested superiority of RVSI to individual intrarenal venous flow patterns in predicting outcome (areas under the curve: 0.789 and 0.761, respectively; P =0.038). Conclusions: We propose RVSI as a conceptually new and integrative Doppler index of renal congestion. RVSI provides additional prognostic information to stratify PH for the propensity to develop right heart failure. Clinical Trial Registration: URL : https://www.clinicaltrials.gov/ . Unique identifier: NCT 03039959.

Critically ill COVID-19 patients are generally admitted to the ICU for respiratory insufficiency which can evolve into a multiple-organ dysfunction syndrome requiring extracorporeal organ support. Ongoing advances in technology and science and progress in information technology support the development of integrated multi-organ support platforms for personalized treatment according to the changing needs of the patient. Based on pathophysiological derangements observed in COVID-19 patients, a rationale emerges for sequential extracorporeal therapies designed to remove inflammatory mediators and support different organ systems. In the absence of vaccines or direct therapy for COVID-19, extracorporeal therapies could represent an option to prevent organ failure and improve survival. The enormous demand in care for COVID-19 patients requires an immediate response from the scientific community. Thus, a detailed review of the available technology is provided by experts followed by a series of recommendation based on current experience and opinions, while waiting for generation of robust evidence from trials.

Critically ill patients developing severe forms multiple organ dysfunction syndrome (MODS) may not be adequately supported by pharmacologic management. In these complex cases, a single form of extracorporeal organ support (ECOS) may be required, but multiple organ support therapy (MOST) is currently seen as a feasible approach. Severe renal dysfunction is a typical syndrome requiring renal replacement therapy (RRT) in the context of MODS. After more than a decade of RRT application in various intensive care settings, ECOS are not anymore seen as extraordinary or particularly aggressive techniques in MODS patients. Nowadays, a significant increase in the use of extracorporeal membrane oxygenation and extracorporeal carbon dioxide removal is occurring. When renal and cardio-pulmonary ECOS are used together, a multidisciplinary approach is necessary to minimize negative interactions and unwanted adverse effects. In this editorial, we focus on the organ crosstalk between the native and artificial organs, including the advantages and disadvantages of organ support on multiorgan function. Much of current experience on MOST has been gained upon RRT connected to other organ support therapies. Overall, available literature has not definitely established the ideal timing of these interventions, and whether early implementation impacts organ recovery and optimizes resource utilization is still a matter of open debate: it is possible that future research will be devoted to identify patient groups that may benefit from short- and long-term multiple organ support. Video Journal Club “Cappuccino with Claudio Ronco” at https://www.karger.com/Journal/ArticleNews/490694?sponsor=52