Abstract Background Cardiovascular disease among hemodialysis (HD) patients is linked to poor outcomes. The Acute Dialysis Quality Initiative Workgroup proposed echocardiographic (ECHO) criteria for ...structural heart disease (SHD) in dialysis patients. The association of SHD with important patient outcomes is not well defined. Objectives This study sought to determine prevalence of ECHO-determined SHD and its association with survival among incident HD patients. Methods We analyzed patients who began chronic HD from 2001 to 2013 who underwent ECHO ≤1 month prior to or ≤3 months following initiation of HD (n = 654). Results Mean patient age was 66 ± 16 years, and 60% of patients were male. ECHO findings that met 1 or more and ≥3 of the new criteria were discovered in 87% and 54% of patients, respectively. Over a median of 2.4 years, 415 patients died: 108 (26%) died within 6 months. Five-year mortality was 62%. Age- and sex-adjusted structural heart disease variables associated with death were left ventricular ejection fraction (LVEF) ≤45% (hazard ratio HR: 1.48; confidence interval CI: 1.20 to 1.83) and right ventricular (RV) systolic dysfunction (HR: 1.68; CI: 1.35 to 2.07). An additive of higher death risk included LVEF ≤45% and RV systolic dysfunction rather than neither (HR: 2.04; CI: 1.57 to 2.67; p = 0.53 for test for interaction). Following adjustment for age, sex, race, diabetic kidney disease, and dialysis access, RV dysfunction was independently associated with death (HR: 1.66; CI 1.34 to 2.06; p < 0.001). Conclusions SHD was common in our HD study population, and RV systolic dysfunction independently predicted mortality.
Background Recent policy clarifications by the Centers for Medicare & Medicaid Services have changed access to outpatient dialysis care at end-stage renal disease (ESRD) facilities for individuals ...with acute kidney injury in the United States. Tools to predict “ESRD” and “acute” status in terms of kidney function recovery among patients who previously initiated dialysis therapy in the hospital could help inform patient management decisions. Study Design Historical cohort study. Setting & Participants Incident hemodialysis patients in the Mayo Clinic Health System who initiated in-hospital renal replacement therapy (RRT) and continued outpatient dialysis following hospital dismissal (2006 through 2009). Predictor Baseline estimated glomerular filtration rate (eGFR), acute tubular necrosis from sepsis or surgery, heart failure, intensive care unit, and dialysis access. Outcomes Kidney function recovery defined as sufficient kidney function for outpatient hemodialysis therapy discontinuation. Results Cohort consisted of 281 patients with a mean age of 64 years, 63% men, 45% with heart failure, and baseline eGFR ≥ 30 mL/min/1.73 m2 in 46%. During a median of 8 months, 52 (19%) recovered, most (94%) within 6 months. Higher baseline eGFR (HR per 10–mL/min/1.73 m2 increase eGFR, 1.27; 95% CI, 1.16-1.39; P < 0.001), acute tubular necrosis from sepsis or surgery (HR, 3.34; 95% CI, 1.83-6.24; P < 0.001), and heart failure (HR, 0.40; 95% CI, 0.19-0.78, P = 0.007) were independent predictors of recovery within 6 months, whereas first RRT in the intensive care unit and catheter dialysis access were not. There was a positive interaction between absence of heart failure and eGFR ≥ 30 mL/min/1.73 m2 for predicting kidney function recovery ( P < 0.001). Limitations Sample size. Conclusions Kidney function recovery in the outpatient hemodialysis unit following in-hospital RRT initiation is not rare. As expected, higher baseline eGFR is an important determinant of recovery. However, patients with heart failure are less likely to recover even with a higher baseline eGFR. Consideration of these factors at hospital discharge informs decisions on ESRD status designation and long-term hemodialysis care.
Abstract Objective We have previously used a 12-lead, signal-processed ECG to calculate blood potassium levels. We now assess the feasibility of doing so with a smartphone-enabled single lead, to ...permit remote monitoring. Patients and methods Twenty-one hemodialysis patients held a smartphone equipped with inexpensive FDA-approved electrodes for three 2 min intervals during hemodialysis. Individualized potassium estimation models were generated for each patient. ECG-calculated potassium values were compared to blood potassium results at subsequent visits to evaluate the accuracy of the potassium estimation models. Results The mean absolute error between the estimated potassium and blood potassium 0.38 ± 0.32 mEq/L (9% of average potassium level) decreasing to 0.6 mEq/L using predictors of poor signal. Conclusions A single-lead ECG acquired using electrodes attached to a smartphone device can be processed to calculate the serum potassium with an error of 9% in patients undergoing hemodialysis. Summary A single-lead ECG acquired using electrodes attached to a smartphone can be processed to calculate the serum potassium in patients undergoing hemodialysis remotely.
Abstract Objective To determine if ECG repolarization measures can be used to detect small changes in serum potassium levels in hemodialysis patients. Patients and Methods Signal-averaged ECGs were ...obtained from standard ECG leads in 12 patients before, during, and after dialysis. Based on physiological considerations, five repolarization-related ECG measures were chosen and automatically extracted for analysis: the slope of the T wave downstroke (T right slope), the amplitude of the T wave (T amplitude), the center of gravity (COG) of the T wave (T COG), the ratio of the amplitude of the T wave to amplitude of the R wave (T/R amplitude), and the center of gravity of the last 25% of the area under the T wave curve (T4 COG) ( Fig. 1 ). Results The correlations with potassium were statistically significant for T right slope ( P < 0.0001), T COG ( P = 0.007), T amplitude ( P = 0.0006) and T/R amplitude ( P = 0.03), but not T4 COG ( P = 0.13). Potassium changes as small as 0.2 mmol/L were detectable. Conclusion Small changes in blood potassium concentrations, within the normal range, resulted in quantifiable changes in the processed, signal-averaged ECG. This indicates that non-invasive, ECG-based potassium measurement is feasible and suggests that continuous or remote monitoring systems could be developed to detect early potassium deviations among high-risk patients, such as those with cardiovascular and renal diseases. The results of this feasibility study will need to be further confirmed in a larger cohort of patients.
To examine long-term outcomes, including all-cause mortality, and the likelihood and timing of renal recovery among patients requiring renal replacement therapy (RRT) for acute kidney injury after ...cardiac surgery.
This is a single-center, historical, matched cohort study of post-cardiac surgery patients who required RRT from January 1, 2007, through December 31, 2012. We matched each case with 2 controls, each of whom did not require RRT after cardiac surgery, for age, sex, and type of surgery. The patients were followed up for 1 year after the start of RRT. The main outcomes were all-cause mortality in all patients and rate of renal function recovery in patients who required RRT.
A total of 202 patients met the inclusion criteria. The unadjusted all-cause mortality among patients requiring RRT was 64% at 1 year vs 8% for matched controls. In multivariate analysis, the hazard ratio for all-cause mortality was 12.59 (95% CI, 8.24-19.68) for cases vs controls. Increased 1-year all-cause mortality was independently associated with increased age, a history of congestive heart failure, lower preoperative creatinine level, longer interval between surgery and starting RRT, and the need for mechanical ventilation or an intra-aortic balloon pump at the time of RRT. Renal recovery occurred in 34% of cases by 90 days and in 39% by 1 year. Of those who recovered renal function, 87% were within 90 days. Only 8 (4%) of the 186 patients were alive and continued to receive RRT at 1 year.
The need for RRT after cardiac surgery is an independent risk factor for mortality. In the case of survival, the chance of renal recovery is reasonable.
To report on the survival and the associations of treatments upon survival of patients with calciphylaxis seen at a single center.
Using the International Classification of Diseases, Ninth Revision ...diagnosis code of 275.49 and the keyword "calciphylaxis" in the dismissal narrative, we retrospectively identified 101 patients with calciphylaxis seen at our institution between January 1, 1999, through September 20, 2014, using a predefined, consensus-developed classification scheme.
The average age of patients was 60 years: 81 (80.2%) were women; 68 (68.0%) were obese; 19 (18.8%) had stage 0 to 2 chronic kidney disease (CKD), 19 (18.9%) had stage 3 or 4 CKD; 63 (62.4%) had stage 5 or 5D (dialysis) CKD. Seventy-five patients died during follow-up. Six-month survival was 57%. Lack of surgical debridement was associated with insignificantly lower 6-month survival (hazard ratio HR=1.99; 95% CI, 0.96-4.15; P=.07) and significantly poorer survival for the entire duration of follow-up (HR=1.98; 95% CI, 1.15-3.41; P=.01), which was most pronounced in stage 5 or 5D CKD (HR=1.91; 95% CI, 1.03-3.56; P=.04). Among patients with stage 5/5D CKD, subtotal parathyroidectomy (performed only in patients with hyperparathyroidism) was associated with better 6-month (HR=0.12; 95% CI, 0.02-0.90; P=.04) and overall survival (HR= 0.37; 95% CI, 0.15-0.87; P=.02).
Calciphylaxis is associated with a high mortality rate. Significantly effective treatments included surgical debridement and subtotal parathyroidectomy in patients with stage 5/5D CKD with hyperparathyroidism. Treatments with tissue-plasminogen activator, sodium thiosulfate, and hyperbaric oxygen therapy were not associated with higher mortality.
Objectives Patients with end-stage renal disease (ESRD) are often excluded from trials comparing off and on-pump coronary artery bypass grafting (CABG). Thus data in this cohort is limited to small ...retrospective studies. Hence we compared the adverse clinical events and outcome in patients with ESRD undergoing off (OPCABG) and on-pump surgery (ONCABG). Methods Pubmed, Scopus and Web of Science were searched (inception – June 2013) to identify studies comparing clinical results of OPCABG and ONCABG in dialysis dependent patients. A random effect inverse variance weighted meta-analysis was conducted. Results are presented as risk ratios (RR) with 95% confidence intervals; p < 0.05 is significant. Result Ten retrospective studies (2762 OPCABG and 11310 ONCABG) fulfilled criteria and were pooled. Patients undergoing off-pump surgery were less than 100 in most of the articles. Early mortality OPCABG (8.4%); ONCABG (10.4%) was comparable RR 0.80(0.51–1.17); p = 0.35; I2 = 30%. Re-exploration for bleeding RR 0.81(0.47–1.39); p = 0.44 and blood transfusion RR 0.79(0.57–1.08); p = 0.14 were also comparable. While patients undergoing off-pump surgery were extubated earlier (p < 0.01), other post-operative events like stroke (p = 0.34) and atrial fibrillation (p = 0.10) were similar. Mid-term survival (three to five years) was also comparable. Conclusion Patients with end-stage renal disease undergoing coronary artery bypass grafting demonstrate comparable results irrespective of method. While available data is limited to retrospective studies, we failed to demonstrate any significant advantage for performing OPCABG in this group of patients.
To identify coagulation risk factors in patients with calciphylaxis and the relationship between anticoagulation use and overall survival.
Study subjects were 101 patients with calciphylaxis seen at ...Mayo Clinic from 1999 to September 2014. Data including thrombophilia profiles were extracted from the medical records of each patient. Survival status was determined using patient registration data and the Social Security Death Index. Survival was estimated using the Kaplan-Meier method, and associations were evaluated using Cox proportional hazards models.
Sixty-four of the 101 patients underwent thrombophilia testing. Of these, a complete test panel was performed in 55 and a partial panel in 9. Severe thrombophilias observed in 60% (33 of 55) of the patients included antiphospholipid antibody syndrome protein C, protein S, or antithrombin deficiencies or combined thrombophilias. Of the 55 patients, severe thrombophilia (85%, 23 of 27) was noted in patients who were not on warfarin at the time of testing (27). Nonsevere thrombophilias included heterozygous factor V Leiden (n=2) and plasminogen deficiency (n=1). For the comparison of survival, patients were divided into 3 treatment categories: Warfarin (n=63), other anticoagulants (n=20), and no anticoagulants (n=18). There was no statistically significant survival difference between treatment groups.
Laboratory testing reveals a strikingly high prevalence of severe thrombophilias in patients with calciphylaxis, underscoring the importance of congenital and acquired thrombotic propensity potentially contributing to the pathogenesis of this disease. These findings may have therapeutic implications; however, to date, survival differences did not vary by therapeutic choice.
Background TNFRSF13B , which encodes transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), is mutated in 10% of patients with common variable immunodeficiency. One ...of the 2 most common TACI mutations in common variable immunodeficiency, C104R, abolishes ligand binding and is found predominantly in the heterozygous state. The murine TACI mutant C76R is the equivalent of the human TACI mutant C104R. Objective We sought to define the consequence of the C76R mutation on TACI function in mice that express both wild-type TACI and the murine C76R mutant. Methods Transgenic mice that express murine TACI C76R, the counterpart of human TACI C104R, on the TACI+/− B6/129 background (C76R/TACI+/− mice) were constructed. Serum immunoglobulins and antibody responses to the type II T-independent antigen trinitrophenylated (TNP)-Ficoll were determined by means of ELISA. B-cell proliferation in response to a proliferation-inducing ligand was determined based on tritiated thymidine incorporation into DNA. IgG1 secretion by B cells in response to a proliferation-inducing ligand plus IL-4 was determined by means of ELISA. Results C76R/TACI+/− mice had significantly impaired antibody responses to the type II T-independent antigen TNP-Ficoll compared with TACI+/+ B6/129 control animals, and their B cells were impaired in their capacity to proliferate and secrete IgG1 in response to TACI ligation. Unexpectedly, TACI+/− mice had similarly impaired B-cell function as C76R/TACI+/− littermates. Impaired TACI function caused by haploinsufficiency was confirmed in TACI+/− mice on the C57BL/6 background. Conclusion These results suggest that the human TACI mutant C104R might impair TACI function in heterozygotes through haploinsufficiency.