Comparative characteristics of postoperative outcomes of different treatment strategies of patients with intermittent claudication in combination with coronary arteries disease.

Aim      To compare in-hospital outcomes (severe cardiovascular complications, CVC) in patients with IIB stage chronic lower limb ischemia (CLLI) in combination with ischemic heart disease (IHD) in the following groups: stepwise percutaneous coronary intervention (PCI) and stenting and angioplasty of lower limb arteries (LLA) (group 1) and combination treatment, including PCI and open surgery on LLA (group 2).Material and methods  Since 2019, the A.V. Vishnevsky National Medical Research Center of Surgery has performed a retrospective study that includes patients with stage IIB CLLI in combination with IHD. Patients were divided into 2 groups: group 1 (n=46), stepwise X-ray endovascular treatment (PCI and stenting and angioplasty of LLA); group 2 (n=46), stepwise combination treatment (PCI and open surgery on LLA). The endpoint included severe CVCs (death, acute myocardial infarction, acute cerebrovascular disease) and severe complications in the LLA area (stent thrombosis, repeated intervention on LLA, amputation).Results In 198 surgeries, none of 92 patients had severe CVC, and no fatal outcomes were observed. In group 2, there was one (2.1 %) severe complication on LLA during the early postoperative period, for which a successful additional intervention was performed.Conclusion      Individualized approach to care of each patient with LLA pathology in combination with IHD helps avoiding severe CVCs at the hospital stage. It was shown that X-ray endovascular and combination treatments are safe and effective in the absence of fatal outcomes and acute disorders of coronary circulation at the hospital stage.

Analysis of threshold-type behaviour in mathematical models of the intrusion of a novel macroparasite in a host colony.

Macroparasites include worms, ticks, mites, bugs and fleas. These parasites are well known to induce morbidity effects including a reduction in the hosts' reproductive output and survival. An important scenario is the introduction of a new macroparasite into an established host population which may be caused by the climate change and by the transport of domestic animals. The aim of the article is to demonstrate an interesting feature of this scenario using a mathematical model with four dimensionless parameters. Six possible scenarios of introducing a new macroparasite into a host colony, ranging from the elimination of the new pathogen, through guaranteed host and parasite coexistence, to the collapse of the host colony are distinguished. The threshold surfaces in the space of parameters which separate the different scenarios are found. Some special limit cases are discussed.