Ratio of Mixed Venous Oxygen Saturation-to-Pulmonary Capillary Wedge Pressure: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program.

BACKGROUND: Hemodynamic values from right heart catheterization aid diagnosis and clinical decision-making but may not predict outcomes. Mixed venous oxygen saturation percentage and pulmonary capillary wedge pressure relate to cardiac output and congestion, respectively. We theorized that a novel, simple ratio of these measurements could estimate cardiovascular prognosis. METHODS: We queried Veterans Affairs' databases for clinical, hemodynamic, and outcome data. Using the index right heart catheterization between 2010 and 2016, we calculated the ratio of mixed venous oxygen saturation-to-pulmonary capillary wedge pressure, termed ratio of saturation-to-wedge (RSW). The primary outcome was time to all-cause mortality; secondary outcome was 1-year urgent heart failure presentation. Patients were stratified into quartiles of RSW, Fick cardiac index (CI), thermodilution CI, and pulmonary capillary wedge pressure alone. Kaplan-Meier curves and Cox proportional hazards models related comparators with outcomes. RESULTS: Of 12 019 patients meeting inclusion criteria, 9826 had values to calculate RSW (median 4.00, interquartile range, 2.67-6.05). Kaplan-Meier curves showed early, sustained separation by RSW strata. Cox modeling estimated that increasing RSW by 50% decreases mortality hazard by 19% (estimated hazard ratio, 0.81 [95% CI, 0.79-0.83], P<0.001) and secondary outcome hazard by 28% (hazard ratio, 0.72 [95% CI, 0.70-0.74], P<0.001). Among the 3793 patients with data for all comparators, Cox models showed RSW best associated with outcomes (by both C statistics and Bayes factors). Furthermore, pulmonary capillary wedge pressure was superior to thermodilution CI and Fick CI. Multivariable adjustment attenuated without eliminating the association of RSW with outcomes. CONCLUSIONS: In a large national database, RSW was superior to conventional right heart catheterization indices at assessing risk of mortality and urgent heart failure presentation. This simple calculation with routine data may contribute to clinical decision-making in this population.

Cost analysis of iliac stenting performed in the operating room and the catheterization lab: A case-control study.

BACKGROUND: Iliac arterial stenting is performed both in the operating room (OR) and the catheterization lab (CL). To date, no analysis has compared resource utilization between these locations. METHODS: Consecutive patients (n = 105) treated at a single center were retrospectively analyzed. Patients included adults with chronic, symptomatic iliac artery stenosis with a minimum Rutherford classification (RC) of 3, treated with stents. Exclusion criteria were prior stenting, acute ischemia, or major concomitant procedures. Immediate and two-year outcomes were observed. Patient demographics, perioperative details, physician billings, and hospital costs were recorded. Multivariable regression was used to adjust costs by patient and perioperative cost drivers. RESULTS: Fifty-one procedures (49%) were performed in the OR and 54 (51%) in the CL. Mean age was 57, and 44% were female. Severe cases were more often performed in the OR (RC ≥ 4; 42% vs. 11%, P < 0.001) and were associated with increased total costs (P < 0.01). OR procedures more often utilized additional stents (stents ≥ 2; 61% vs. 46%, P = 0.214), thrombolysis (12% vs. 0%, P = 0.011), cut-down approach (8% vs. 0%, P = 0.052), and general anesthesia (80% vs. 0%, P < 0.001): these were all associated with increased costs (P < 0.05). After multivariable regression, location was not a predictor of procedure room or total costs but was associated with increased professional fees. Same-stay (5%) and post-discharge reintervention (33%) did not vary by location. CONCLUSIONS: The OR was associated with increased length of stay, more ICU admissions, and increased total costs. However, OR patients had more severe disease and therefore often required more aggressive intervention. After controlling for these differences, procedure venue per se was not associated with increased costs, but OR cases incurred increased professional fees due to dual-provider charges. Given the similar clinical results between venues, it seems reasonable to perform most stenting in the CL or utilize conscious sedation in the OR.

Is there an association between external cardioversions and long-term mortality and morbidity? Insights from the Atrial Fibrillation Follow-up Investigation of Rhythm Management study.

BACKGROUND: Cardiac electric therapies effectively terminate tachyarrhythmias. Recent data suggest a possible increase in long-term mortality associated with implantable cardioverter-defibrillator shocks. Little is known about the association between external cardioversion episodes (ECVe) and long-term mortality. We sought to assess the safety of repeated ECVe with regard to cardiovascular mortality and morbidity. METHODS AND RESULTS: We analyzed the data of the 4060 patients from the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) trial. In particular, associations of ECVe with all-cause mortality, cardiovascular mortality, and hospitalizations after ECVe were studied. Over an average follow-up of 3.5 years, 660 (16.3%) patients died, 331 (8.2%) from cardiovascular causes. A total of 207 (5.1%) and 1697 (41.8%) patients had low ejection fraction and nonparoxysmal atrial fibrillation, respectively; 2460 patients received no ECVe, whereas 1600 experienced ≥ 1 ECVe. Death occurred in 412 (16.7%), 196 (16.5%), 39 (13.5%), and 13 (10.4%) of patients with 0, 1, 2, and ≥ 3 ECVe, respectively. There was no significant association between ECVe and mortality within any of the 4 subgroups defined by ejection fraction and atrial fibrillation type, although myocardial infarction, coronary artery bypass graft, and digoxin were significantly associated with death (estimated hazard ratios, 1.65, 1.59, and 1.62, respectively; P < 0.0001). ECVe were associated with increased cardiac hospitalization reported at the next follow-up visit (39.3% versus 5.8%; estimated odds ratio, 1.39; P < 0.0001). CONCLUSIONS: In the AFFIRM study, there was no significant association between ECVe and long-term mortality, even though ECVe were associated with increased hospitalizations from cardiac causes. Digoxin, myocardial infarction, and coronary artery bypass graft were significantly associated with mortality.