Strategy of pacemaker and electrode replacement for superior vena cava stenosis.

Cardiac implantable devices are commonly used for superior vena cava stenosis, but there have been few reports of electrode replacement in the stenosed superior vena cava. A 73-year-old man was diagnosed with second-degree type II atrioventricular block and a permanent dual-chamber, rate-modulated pacing pacemaker was implanted 10 years previously. Because of depletion of the pacemaker battery and an increase in the ventricular pacing threshold, replacement of the pacemaker and ventricular electrode was required. During the operation, we found that the patient had severe superior vena cava stenosis on angiography, and this caused obstruction when a common guidewire was used to pass through the superior vena cava. After attempting various methods, we successfully passed through the vascular stenosis with a super slide guidewire and a long sheath, and completed replacement of the pacemaker and ventricular electrode. We summarize the related literature of superior vena cava stenosis related to a cardiac implantable device, and discuss the replacement strategy of this complication and other treatment options.

Establishment of risk prediction model and risk score for in-hospital mortality in patients with AECOPD.

OBJECTIVE: Risk stratification for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) may help clinicians choose appropriate treatments and improve the quality of care. METHODS: A total of 695 patients hospitalized with AECOPD from January 2015 to December 2017 were considered. They were assigned to a death and a survival cohort. The independent prognostic factors were determined by multivariate logistic regression analysis. Meanwhile, we also compared the new scale with three other scores and tested the new scale internally and externally. RESULTS: A new risk score was created, made up of six independent variables: age, D-dimer, albumin, cardiac troponin I, partial pressure of carbon dioxide and oxygenation index. The area under the receiver operator characteristic curve (AUROC) for the model was 0.929, and the other three CURB-65, DECAF and BAP-65 models were 0.718, 0.922 and 0.708. The Cohen's kappa coefficient between the new scale and DECAF was calculated to be 0.648, suggesting that there is a substantial consistency between the two. In the internal and external validation cohorts, 490 and 500 patients were recruited with a total mortality rate of 5.15%. The AUROC for in-hospital mortality was 0.937 in the internal cohort and 0.914 in external cohort, which was significantly better than the scores for CURB-65 and BAP-65, but it was not significantly different from the DECAF. CONCLUSIONS: The new scale may help to stratify the risk of in-hospital mortality of AECOPD. The DECAF performed as well as the new instrument, and it appears to be valid in Chinese patients.

Left atrial myxoma complicated with multi-system embolization.

BACKGROUND: Atrial myxoma accounts for approximately 50% of all cardiac tumors. The majority of myxomas are located in the left atrium and present variable clinical manifestation. CASE PRESENTATION: A young man was transferred to our hospital with sudden onset of resting pain, pallor and numb in right leg. An atrial mobile mass was detected by transthoracic echocardiography. Anticoagulant and antithrombotic therapy were administered, a timely surgery was performed and the mass was confirmed as a myxoma. The patient did not discharge any discomfort post-operation. CONCLUSION: For patients with atrial myxoma, early diagnosis is essential, anticoagulant or antithrombotic therapy and surgery have a great importance to prevent further embolism.

[Design and verification of Luo-Ye pump-based stress formation for cultivation of tissue-engineered blood vessel].

OBJECTIVE: To improve Luo-Ye pump-based stress-forming system and optimize the stimulating effect on smooth muscle cells during cultivation of tissue-engineered blood vessels (TEBV). METHODS: A new Luo-Ye pump-based TEBV 3D culture system was developed by adding an air pump to the output of the bioreactor. A pressure guide wire was used to measure the stress at different points of the silicone tube inside the TEBV bio-reactor, and fitting curves of the stress changes over time was created using Origin 8.0 software. The TEBVs were constructed by seeding vascular smooth muscle cells (VSMCs) isolated from human umbilical artery on polyglycolic acid (PGA) and cultured under dynamic conditions with 40 mmHg resistance (improved group), dynamic conditions without resistance (control group) or static condition (static group) for 4 weeks. The harvested TEBVs were then examined with HE staining, masson staining, α-SMA immunohistochemical staining, and scanning and transmission electron microscopy with semi-quantitative analysis of collagen content and α-SMA expression. RESULTS: The measured stress values and the fitting curves showed that the stress stimuli from the Luo-Ye pump were enhanced by adding an air pump to the output of the bioreactor. Histological analysis revealed improved VSMC density, collagen content and α-SMA expression in the TEBVs constructed with the improved method as compared with those in the control and static groups. CONCLUSION: Adding an air pump to the Luo-Ye pump significantly enhances the stress stimulation in the TEBV 3-D culture system to promote the secretion function of VSMCs.

Development of contrast-induced acute kidney injury after elective contrast media exposure in patients with type 2 diabetes mellitus: effect of albuminuria.

BACKGROUND: The influence of albuminuria and urinary pH on the development of contrast-induced acute kidney disease (CI-AKI) in patients with type 2 diabetes mellitus (T2DM) after elective coronary angiography (CAG) or percutaneous coronary intervention (PCI) is unknown. METHODS: CI-AKI was defined as an increase in serum creatinine >26.4 µmol/L or ≥50% of baseline value within 48 hours after contrast media exposure. Demographics, traditional risk factors, clinical outcomes and CI-AKI incidence were compared between groups. Univariate analysis and multivariate logistic regression were performed to assess risk factors of CI-AKI. RESULTS: We observed 597 patients with T2DM after CAG or PCI. Patients were divided into 3 groups based on early morning urinary albumin: negative group (urine dipstick negative, n = 483), trace group (urine dipstick trace, n = 60), and positive group (urine dipstick ≥1+, n = 54). CI-AKI occurred in 33 (5.5%) patients, including 19 (3.9%) in the negativealbuminuria group, 4 (6.7%) in the trace group, and 10 (18.5%) in the positive group (p< 0.001), respectively. After adjusting for potential confounding risk factors, positive albuminuria (OR = 3.8, 95% CI: 1.5 to 9.2, p = 0.004) and urinary pH<6 (OR = 2.4, 95% CI: 1.1 to 5.1, p = 0.020) remained significantly associated with CI-AKI. CONCLUSION: Preprocedural albuminuria and urinary pH <6 are independent risk factors of CI-AKI in patients with T2DM undergoing elective cardiac catheterization, and may be used to identify patients at high risk of post-procedural CI-AKI.