Which method of estimating renal function is the best predictor of mortality after coronary artery bypass grafting?

OBJECTIVES: Definitions of renal function in patients undergoing coronary artery bypass graft surgery (CABG) vary in the literature. We sought to investigate which method of estimating renal function is the best predictor of mortality after CABG. METHODS: We analysed the preoperative and postoperative renal function data from all patients undergoing isolated CABG from January 1998 through December 2007. Preoperative and postoperative renal function was estimated using serum creatinine (SeCr) levels, creatinine clearance (CrCl) determined by the Cockcroft-Gault formula and the glomerular filtration rate (e-GFR) estimated by the Modification of Diet in Renal Disease (MDRD) formula. Receiver operator characteristic (ROC) curves and area under the ROC curves were calculated. RESULTS: In 9987 patients, CrCl had the best discriminatory power to predict early as well as late mortality, followed by e-GFR and finally SeCr. The odds ratios for preoperative parameters for early mortality were closer to 1 than those of the postoperative parameters. CONCLUSIONS: Renal function determined by the Cockcroft-Gault formula is the best predictor of early and late mortality after CABG. The relationship between renal function and mortality is non-linear. Renal function as a variable in risk scoring systems such as the EuroSCORE needs to be reconsidered.

Evaluation of the EuroSCORE risk scoring model for patients undergoing coronary artery bypass graft surgery: a word of caution.

Background. Risk-adjusted mortality rates are used to compare quality of care of different hospitals. We evaluated the EuroSCORE (European System for Cardiac Operative Risk Evaluation) in patients undergoing isolated coronary artery bypass grafting (CABG).Patients and method. Data of all CABG patients from January 2004 until December 2008 were analysed. Receiver-operating characteristics (ROC) curves for the additive and logistic EuroSCOREs and the areas under the ROC curve were calculated. Predicted probability of hospital mortality was calculated using logistic regression analyses and compared with the EuroSCORE. Cumulative sum (CUSUM) analyses were performed for the EuroSCORE and the actual hospital mortality.Results. 5249 patients underwent CABG of which 89 (1.7%) died. The mean additive EuroSCORE was 3.5+/-2.5 (0-17) (median 3.0) and the mean logistic EuroSCORE was 4.0+/-5.5 (0-73) (median 2.4). The area under the ROC curve was 0.80+/-0.02 (95% confidence interval (CI) 0.76 to 0.84) for the additive and 0.81+/-0.02 (0.77 to 0.85) for the logistic EuroSCORE. The predicted probability (hazard ratio) was different from the additive and logistic EuroSCOREs. The hospital mortality was half of the EuroSCOREs, resulting in positive variable life-adjusted display curves. Conclusions. Both the additive and logistic EuroSCOREs are overestimating the in-hospital mortality risk in low-risk CABG patients. The logistic EuroSCORE is more accurate in high-risk patients compared with the additive EuroSCORE. Until a more accurate risk scoring system is available, we suggest being careful when comparing the quality of care of different centres based on risk-adjusted mortality rates. (Neth Heart J 2010;18:355-9.).

Symptom dimensions of post-myocardial infarction depression, disease severity and cardiac prognosis.

BACKGROUND: Individual symptoms of post-myocardial infarction (MI) depression may be differentially associated with cardiac prognosis, in which somatic/affective symptoms appear to be associated with a worse cardiovascular prognosis than cognitive/affective symptoms. These findings hold important implications for treatment but need to be replicated before conclusions regarding treatment can be drawn. We therefore examined the relationship between depressive symptom dimensions following MI and both disease severity and prospective cardiac prognosis. METHOD: Patients (n=473) were assessed on demographic and clinical variables and completed the Beck Depression Inventory (BDI) within the first week of hospital admission for acute MI. Depressive symptom dimensions were associated with baseline left ventricular ejection fraction (LVEF) and prospective cardiac death and/or recurrent MI. The average follow-up period was 2.8 years. RESULTS: Factor analysis revealed two symptom dimensions--somatic/affective and cognitive/affective--in the underlying structure of the BDI, identical to previous results. There were 49 events attributable to cardiac death (n=23) or recurrent MI (n=26). Somatic/affective (p=0.010) but not cognitive/affective (p=0.153) symptoms were associated with LVEF and cardiac death/recurrent MI. When controlling for the effects of previous MI and LVEF, somatic/affective symptoms remained significantly predictive of cardiac death/recurrent MI (hazard ratio 1.31, 95% confidence interval 1.02-1.69, p=0.038). Previous MI was also an independent predictor of cardiac death/recurrent MI. CONCLUSIONS: We confirmed that somatic/affective, rather than cognitive/affective, symptoms of depression are associated with MI severity and cardiovascular prognosis. Interventions to improve cardiovascular prognosis by treating depression should be targeted at somatic aspects of depression.

Type D personality and depressive symptoms are independent predictors of impaired health status following acute myocardial infarction.

OBJECTIVE: In this prospective follow-up study we investigated whether the type D personality construct (the tendency to experience negative emotions and to be socially inhibited) exerts an independent effect on disease-specific health status in post-myocardial infarction (MI) patients, after adjustment for disease severity and depressive symptoms. METHODS: Patients (n = 503) were assessed on demographic and clinical variables and completed the type D scale (DS14) and Beck Depression Inventory (BDI) within the first week of hospital admission for acute MI. Two months post-MI, all patients completed the WHO Composite International Diagnostic Interview (CIDI) interview. After 18 months, they filled out the Seattle Angina Questionnaire (SAQ) to assess disease-specific health status. RESULTS: At follow-up, type D patients had significantly lower mean scores on all SAQ subscales, indicating worse disease-specific health status, compared to non-type D patients (all p values <0.01). After adjustment for disease severity and depression in multivariate analysis, type D patients still had more physical limitations (mean SAQ score: 49 versus 54; p = 0.014), less angina stability (62 versus 71; p = 0.002) and a less accurate disease perception (52 versus 61; p < or = 0.001) compared with non-type D patients. Depressed patients (BDI > or = 10) also reported significantly lower SAQ scores compared to non-depressed patients. CONCLUSIONS: The type D construct is an independent predictor of impaired disease-specific health status. Type D personality, in addition to depression, may thus be an important psychological factor that deserves attention during the period of rehabilitation in post-MI patients.

Virtual reality laparoscopic nephrectomy simulator is lacking in construct validity.

BACKGROUND AND PURPOSE: Several training models have been developed to improve surgeons' operative skills as well as patient outcomes. Before implementing these models in training programs, their usefulness and accuracy need to be assessed. In this study, we examined the ability of a laparoscopic nephrectomy (LN) virtual reality (VR) simulator to distinguish between different levels of expertise (construct validity). METHODS: Twenty-two novices (no LN experience), 32 intermediates (<10 LN procedures performed) and 10 experienced urologists (> or =10 LN procedures performed) performed the same retroperitoneal task on the LN VR simulator (Mentice, Sweden) three times, performing a practice task before and after the second time. Outcome parameters were time, blood loss, path length, and total score (combination of 62 different parameters). RESULTS: No significant differences were found between intermediate and experienced participants. Task 3 performance showed no significant difference between any of the groups. Both intermediates and experienced participants were significantly faster than novices on the first two tasks and had a better total score. Learning curves of intermediate and experienced participants were flat after task two. CONCLUSIONS: The LN-VR simulator did not distinguish between intermediate and experienced participants. The analysis of the learning curves suggests that the tasks measured dexterity in using the simulator rather than an actual improvement of operative skills. We conclude that the LN-VR simulator does not have sufficient construct validity and is therefore, in its present form, not suitable for implementation in a urologic training program.

Incidence of re-operation and subjective outcome following in situ decompression of the ulnar nerve at the cubital tunnel.

The purpose of this investigation was to determine the failure rate of in situ decompression for cubital tunnel syndrome as determined by the need for additional surgery. We performed a comprehensive chart review of 56 adult patients who had undergone in situ decompression for cubital tunnel syndrome in 69 extremities with more than 1 year follow-up. The patients completed a comprehensive questionnaire concerning preoperative and postoperative pain, numbness, and weakness. After decompression, symptoms were improved substantially or resolved. Five limbs (7%) with persistent symptoms postoperatively were treated successfully with anterior submuscular transposition. These data suggest that in situ decompression of the ulnar nerve is a reliable treatment for cubital tunnel syndrome and has a low failure rate. The uncommon patient with continued symptoms after decompression can be treated effectively with transposition of the ulnar nerve.

Depression and anxiety as predictors of heart rate variability after myocardial infarction.

BACKGROUND: Reduced heart rate variability (HRV) is a prognostic factor for cardiac mortality. Both depression and anxiety have been associated with increased risk for mortality in cardiac patients. Low HRV may act as an intermediary in this association. The present study examined to what extent depression and anxiety differently predict 24-h HRV indices recorded post-myocardial infarction (MI). METHOD: Ninety-three patients were recruited during hospitalization for MI and assessed on self-reported symptoms of depression and anxiety. Two months post-MI, patients were assessed on clinical diagnoses of lifetime depressive and anxiety disorder. Adequate 24-h ambulatory electrocardiography data were obtained from 82 patients on average 78 days post-MI. RESULTS: In unadjusted analyses, lifetime diagnoses of major depressive disorder was predictive of lower SDNN [standard deviation of all normal-to-normal (NN) intervals; beta=-0.26, p=0.022] and SDANN (standard deviation of all 5-min mean NN intervals; beta=0.25, p=0.023), and lifetime anxiety disorder of lower RMSSD (root mean square of successive differences; beta=-0.23, p=0.039). Depression and anxiety symptoms did not significantly predict HRV. After adjustment for age, sex, cardiac history and multi-vessel disease, lifetime depressive disorder was no longer predictive of HRV. Lifetime anxiety disorder predicted reduced high-frequency spectral power (beta=-0.22, p=0.039) and RMSSD (beta=-0.25, p=0.019), even after additional adjustment of anxiety symptoms. CONCLUSIONS: Clinical anxiety, but not depression, negatively influenced parasympathetic modulation of heart rate in post-MI patients. These findings elucidate the physiological mechanisms underlying anxiety as a risk factor for adverse outcomes, but also raise questions about the potential role of HRV as an intermediary between depression and post-MI prognosis.

Cardiac history, prior depression and personality predict course of depressive symptoms after myocardial infarction.

BACKGROUND: Although many studies have focused on post-myocardial infarction (MI) depression, there is limited information about the evolution and determinants of depressive symptoms in the first year post-MI. Therefore we examined (1) the course of depressive symptoms during the first year post-MI and (2) the predictors of these symptom trajectories. METHOD: To assess depressive symptoms, 287 patients completed the Beck Depression Inventory during hospitalization for MI, and 2, and 12 months post-MI. Personality was assessed with the Type-D scale during hospitalization. We used latent class analysis to examine the evolution of depressive symptoms over a 1-year period and multinomial logit regression analyses to examine predictors of these symptom trajectories. RESULTS: The course of depressive symptoms was stable during the first year post-MI. Four groups were identified and classified as non-depressed [40%, intercept (IC) 2.52], mildly depressed (42%, IC 6.91), moderately depressed (14%, IC 13.73) or severely depressed (4%, IC 24.54). In multivariate analysis, cardiac history (log OR(severe) 2.93, p=0.02; log OR(moderate) 1.81, p=0.02; log OR(mild) 1.46, p=0.01), history of depression (log OR(severe) 4.40, p<0.001; log OR(moderate) 1.97, p=0.03) and Type-D personality (log OR(severe) 4.22, p<0.001; log OR(moderate) = 4.17, p<0.001; log OR(mild) 1.66, p=0.02) were the most prominent risk factors for persistence of depressive symptoms during the first year post-MI. CONCLUSIONS: Symptoms of depression tend to persist during the first year post-MI. Cardiac history, prior depression and Type-D personality were identified as independent risk factors for persistence of depressive symptoms. The results of this study strongly argue for routine psychological screening during hospitalization for acute MI in order to identify patients who are at risk for chronicity of depressive symptoms and its deleterious effects on prognosis.