Risk Factors for Bleeding in Hospitalized at Risk Patients With an INR of 5 or More Treated With Vitamin K Antagonists

Various predictive scores for vitamin K antagonist (VKA)-related bleeding have been developed and validated in outpatients and in patients treated for specific indications (when VKAs are used under optimal therapeutic conditions). However, there are few published data on the evaluation of bleeding risk factors in hospitalized, at-risk patients (with a high international normalized ratio [INR]) treated with VKAs. The objective of the present study was to identify the most relevant bleeding risk factors in 906 VKA-treated patients with an INR of 5 or more hospitalized in a French university medical center.Over a 2-year period, we screened all consecutive VKA-treated adults with a risk of major bleeding (defined as an INR ≥ 5 on admission). Demographic and clinical characteristics, medications, and bleeding characteristics were recorded prospectively.The overall incidence of bleeding was 26.6% (serious bleeding: 21.4%; fatal bleeding: 5.4%). An INR ≥ 8.5, a history of recent digestive tract lesions, trauma in the preceding 2 weeks, and known noncompliance were independent risk factors for bleeding and serious bleeding.Our present findings emphasize that VKAs should not be prescribed to patients with a high risk of bleeding (noncompliant patients and those with recent trauma or recent gastrointestinal lesions). It is essential to monitor the INR on a frequent basis and adjust oral anticoagulant treatment appropriately.     

Best quality indicator of vitamin K antagonist therapy to predict mortality and bleeding in haemodialysis patients with atrial fibrillation

BackgroundThere is a high prevalence of atrial fibrillation (AF) in patients undergoing haemodialysis. Oral anticoagulant therapy with vitamin K antagonists (VKAs) is the only accepted treatment for the prevention of thromboembolism in haemodialysis patients with AF. However, in this population, the risk of bleeding is greatly increased. The aim of the study was to evaluate the ability of treatment quality indicators of VKA therapy to predict mortality and bleedings in a population of haemodialysis patients with AF.Materials and methodsA total of 129 patients were included in this cohort study. Deaths and bleeding events were recorded during a follow-up of 4 years. In all patients, International Normalized Ratio (INR) values were assessed at least once a month. Time in therapeutic range (TTR) and INR variability, as measured by the standard deviation of INR, were updated at each INR measurement. A Cox model with time-dependent co-variates and sandwich variance was applied.ResultsDuring follow-up, 71 patients died and 55 bleeding episodes occurred in 31 patients. INR variability was the only indicator associated with both mortality (hazard ratio [HR]=1.67, 95% confidence interval [CI] 1.12; 2.49, p=0.012) and bleeding (HR=2.85, 95% CI: 1.71; 4.75, p=0.0001). HR of mortality was higher in patients with INR >3 (HR=2.06, 95% CI: 1.09; 3.88, p=0.0259) than in subjects in therapeutic range 2<INR≤3. TTR was inversely associated with the risk of recurrent haemorrhagic events (HR=0.88, 95% CI: 0.80; 0.95, p=0.0023), but not with a first episode of bleeding. Results were consistent after censoring patients at VKA withdrawal.DiscussionOur study suggests that, in haemodialysis patients with AF taking VKAs, INR variability is the quality indicator that best predicts clinical outcomes. In this population, if more treatment quality indicators are considered together, it may become easier to identify patients at particularly high risk of bleeding and death.     

Obesity negatively impacts outcome in elderly female patients with aggressive B‐cell lymphomas treated with R‐CHOP: results from prospective trials of the German high grade non‐Hodgkin's lymphoma trial group

To study if obesity is a risk factor in elderly patients (>60 years) with aggressive B‐cell lymphoma, the outcomes of 576 elderly patients treated with rituximab in the RICOVER‐60 trial were analysed in a retrospective study with regard to body mass index (BMI) and gender. Of the 576 patients, 1% had low body weight (BMI < 18·5), 38% were normal weight (18·5 ≤ BMI < 25), 42% were overweight (25 ≤ BMI < 30) and 19% were obese (BMI ≥ 30). Event‐free (EFS), progression‐free (PFS) and overall survival (OS) according to BMI showed no significant differences for all and for male patients. EFS (P = 0·041), PFS (P = 0·038) and OS (P = 0·031) were significantly better for female non‐obese patients. A multivariate analysis adjusted for International Prognostic Index risk factors confirmed these results, with the following hazard ratios (HR) for obesity (BMI ≥ 30) for EFS/PFS/OS: all patients – 1·4/1·4/1·4 (not significant); male patients – 1·2/1·2/1·0 (not significant) and female patients – 1·7 (P = 0·032)/1·9 (P = 0·022)/2·0 (P = 0·017). In conclusion, obesity is a risk factor that influences treatment outcome in elderly female patients with aggressive B‐cell lymphoma treated with R‐CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, prednisolone). The inferior outcomes in obese female patients may be due to faster rituximab clearance in obese females.     

Prediction of significant bleeding during vitamin K antagonist treatment for venous thromboembolism in outpatients

Bleeding is the most concerning complication associated with anticoagulant therapy but poorly characterized and important for risk/benefit assessment. We developed a risk stratification score to predict vitamin K antagonist (VKA)-associated bleeding in venous thromboembolism (VTE) using the UK Clinical Practice Research Datalink. Significant bleeding events in outpatients consisted of major bleeding and clinically relevant non-major bleeding requiring hospitalisation (CRNMB-H) within 90 days of VKA initiation. A scoring scheme for predicting bleeding was developed from subhazard ratios, validated using cross-validation and expressed by the C-statistic. The study cohort consisted of 10,010 patients with first VTE receiving initial VKA treatment, mean age 62·2 years. Between 2008 and 2016, 167 significant bleeding events were recorded (1·7%), i.e. incidence rate was 7·4/100 person-years. Independent predictors for community-acquired significant bleeding included active cancer, trauma/surgical procedure, male gender, dementia, liver disease, anaemia, history of bleeding, cerebrovascular, renal and chronic pulmonary disease, VTE presenting as pulmonary embolism and age over 75. The overall C-statistic was 0·68 (95% CI, 0·60–0·76), 0·75 (0·60–0·88) for major bleeding and 0·65 (0·55–0·75) for CRNMB-H, and higher than in other risk schemes applied to our study population. The developed risk score may identify patients having a significant bleeding risk, in particular major bleeding events, in outpatients.     

Warfarin anticoagulation reversal: management of the asymptomatic and bleeding patient

The management of patients with supra-therapeutic INR in a common clinical problem. The risk of bleeding is influenced by the intensity, variability and duration of anticoagulation, patient age, presence of co-morbidities and concomitant drug therapy. For the asymptomatic patient, warfarin discontinuation is all that is usually required but for individuals at high risk of bleeding and those with INR > 10, oral vitamin K administration is recommended. In the presence of major bleeding, treatment with intravenous vitamin K and prothrombin complex concentrate is the most effective therapy.     

Difficulties encountered by the very elderly with atrial fibrillation on warfarin attending an outpatient anticoagulant monitoring service

IntroductionWarfarin is effective in reducing the stroke risk in atrial fibrillation in the very elderly. This survey aimed to define characteristics and problems of patients aged ≥ 80 with atrial fibrillation attending an outpatient anticoagulant monitoring service (AMS) in a university hospital.MethodsAll patients aged  ≥ 80 from October 2007 to March 2008 were included.ResultsOne hundred and sixty-eight patients, average age 85.8 ± 3.1 years, were included in the study. Average age of commencement was 81.3 ± 4.5 years. Average length of time on warfarin was 4.8 ± 3.3 years. Fifty-three percent of patients managed their own warfarin and took instructions for dosing. In their entire period on warfarin, 61% of patients had problems including bleeding, bruising, falls, medication interactions and erratic International Normalized Ratio (INR) readings. Seven percent of patients had INR readings of > 8.0, necessitating emergency department assessment for reversal with vitamin K. The AMS staff had difficulty contacting 13% of patients with elevated INRs and missed appointments in 11%. In the 6 months, only 45% remained within target INR range of 2.5 ± 0.75 in 90–100% of 10 consecutive readings. Sixteen percent were within target INR in ≤ 60% of readings. Seven percent of patients died, one from a subdural haemorrhage postfall. Fifteen percent were admitted to hospital.DiscussionThe findings illustrate significant difficulties encountered by this elderly, vulnerable age group in proven effective treatment in atrial fibrillation. Changes need to be made to increase resources for monitoring in the community, including home visits, portable INR monitors and point-of-contact dose adjustment. Patients should be assessed carefully for risk to benefit ratio.     

Minor bleeds alert for subsequent major bleeding in patients using vitamin K antagonists

Vitamin K antagonists (VKA) are effective in primary and secondary prevention of thromboembolism, but the associated risk of bleeding is an important limitation. The majority of bleeds are clinically mild. In this study, we assessed whether these minor bleeds are associated with major bleeding, when controlling for other important risk indicators, including the achieved quality of anticoagulation. For this, 5898 patients attending a specialized anticoagulation clinic were retrospectively studied for 1 year after initiation of VKA therapy. The risk of major bleeding was estimated using a multivariate piecewise exponential model with time‐varying exposure for occurring minor bleeds. In patients with a minor bleed (N = 1015) subsequent major bleeding occurred more frequently than in patients without a minor bleed (N = 4883), with an incidence rate of 2·3 [95% confidence interval (CI) 1·4–3·7] vs. 1·2 per 100 person‐years (95% CI 0·9–1·7). The adjusted relative risk of subsequent major bleeding after a minor bleed was 2·9 (95% CI 1·1–7·2, P = 0·024). The percentage of time that a patient had an International Normalized Ratio (INR) above 5 was also independently associated with major bleeding, with a 2·2‐fold increased risk in patients with at least 9% of time above INR 5 (95% CI 1·3–4·0, P = 0·006). Minor bleeds alert for subsequent major bleeding, independent of the quality of anticoagulation.     

Emergency reversal of anticoagulation with vitamin K antagonists with 3-factor prothrombin complex concentrates in patients with major bleeding

Major bleeding is a serious and potentially fatal complication of treatment with vitamin K antagonists (VKAs). Prothrombin complex concentrates (PCCs) can substantially shorten the time needed to reverse VKA effects. To determine the efficacy and safety of 3-factor PCCs for the rapid reversal of VKAs in patients with major bleeding. Patients receiving VKAs and suffering from acute major bleeding were eligible for this prospective cohort study if their international normalized ratio (INR) was higher than or equal to 2.0. Stratified 35–50 IU kg^?1 PCC doses were infused based on initial INR. A total of 126 patients (62 males; mean age: 74 years, range 37–96 years) were enrolled. The mean INR at presentation was 3.3 (range 2–11). At 30 min after PCC administration the mean INR was 1.4 (range: 0.9–3.1), declining to less than or equal to 1.5 in 75 % of patients. The benefit of PCC was maintained for a long time, since in 97 % of all post-infusion time points through 96 h the mean INR remained lower than or equal to 1.5 (mean: 1.19; range: 0.9–2.3). During hospitalization neither thrombotic complications nor significant adverse events were observed and 12 patients died (10 %); none of the deaths was judged to be related to PCC administration. 3-factor PCC administration is an effective, rapid ad safe treatment for the urgent reversal of VKAs in patients with acute major bleeding. Broader use of PCC in this clinical setting appears to be appropriate.     

Suboptimal use of pharmacological venous thromboembolism prophylaxis in cirrhotic patients

Background

Cirrhosis was previously perceived as a haemorrhagic disease state due to frequent associations with coagulopathy and bleeding. However, the coagulopathy of cirrhosis is complex with defects in both procoagulant and anticoagulant factors. Derangements in common laboratory indices of coagulation do not accurately reflect bleeding risk or protection from thrombotic events.

Aims

To assess the rate of pharmacological prophylaxis for venous thromboembolism (VTE) among hospital inpatients with cirrhosis and analyse factors associated with prophylaxis being inappropriately withheld.

Methods

A retrospective cohort study was performed in a tertiary teaching hospital. Patients included were admitted for greater than 48 h with discharge diagnosis codes corresponding to chronic liver disease and/or cirrhosis. The use of VTE chemoprophylaxis with enoxaparin was assessed in cirrhotic patients and non‐cirrhotic controls. Patient data collected included contraindications to prophylaxis, known high‐risk varices, international normalised ratio (INR), creatinine, bilirubin, haemoglobin and platelet count.

Results

Of 108 patients with cirrhosis eligible for VTE prophylaxis, 61 (56.5%) received prophylaxis compared to 104 (96.3%) non‐cirrhotic patients. Platelets and INR were significantly different between those who did and did not receive VTE prophylaxis. On multivariate analysis, platelet count and INR were independent predictors for VTE not being administered.

Conclusion

The administration of chemoprophylaxis in accordance with the hospital guidelines was suboptimal in patients with cirrhosis. Platelet count and INR were independent predictors of prophylaxis use. Our results suggest persistent misperceptions that prolonged INR and thrombocytopenia predict bleeding risk in cirrhosis.     

Effective Response Metric: a novel tool to predict relapse in childhood acute lymphoblastic leukaemia using time‐series gene expression profiling

Accurate risk assignment in childhood acute lymphoblastic leukaemia is essential to avoid under‐ or over‐treatment. We hypothesized that time‐series gene expression profiles (GEPs) of bone marrow samples during remission‐induction therapy can measure the response and be used for relapse prediction. We computed the time‐series changes from diagnosis to Day 8 of remission‐induction, termed Effective Response Metric (ERM‐D8) and tested its ability to predict relapse against contemporary risk assignment methods, including National Cancer Institutes (NCI) criteria, genetics and minimal residual disease (MRD). ERM‐D8 was trained on a set of 131 patients and validated on an independent set of 79 patients. In the independent blinded test set, unfavourable ERM‐D8 patients had >3‐fold increased risk of relapse compared to favourable ERM‐D8 (5‐year cumulative incidence of relapse 38·1% vs. 10·6%; P = 2·5 × 10⁻³). ERM‐D8 remained predictive of relapse [P = 0·05; Hazard ratio 4·09, 95% confidence interval (CI) 1·03–16·23] after adjusting for NCI criteria, genetics, Day 8 peripheral response and Day 33 MRD. ERM‐D8 improved risk stratification in favourable genetics subgroups (P = 0·01) and Day 33 MRD positive patients (P = 1·7 × 10⁻³). We conclude that our novel metric – ERM‐D8 – based on time‐series GEP after 8 days of remission‐induction therapy can independently predict relapse even after adjusting for NCI risk, genetics, Day 8 peripheral blood response and MRD.     

Time in Therapeutic Range With Vitamin K Antagonists in Congenital Heart Disease: A Multicentre Study

BackgroundVitamin K antagonists (VKAs) are frequently prescribed to patients with congenital heart disease (CHD) for atrial arrhythmias or Fontan palliation, but there is a paucity of data regarding time spent in the therapeutic range (TTR). We sought to determine the TTR in patients with CHD and atrial arrhythmias or Fontan palliation prescribed VKAs and explore associations with thromboembolic and bleeding events.MethodsA multicentre North American cohort study was conducted on patients with CHD who received VKAs for sustained atrial arrhythmia or Fontan palliation. TTR was calculated using the Rosendaal linear interpolation method. Generalized estimating equations were used to explore factors associated with time outside the therapeutic range.ResultsA total of 567 patients, aged 33 ± 17 years, 56% female, received VKAs for 11.5 ± 8.4 years for atrial arrhythmias (63.0%) or Fontan palliation (58.0%). CHD was simple, moderate, and complex in 10.8%, 20.3%, and 69.0%, respectively. Site investigators perceived good control over international normalized ratio (INR) levels in most patients (75.3%), with no or minor compliance or adherence issues (85.6%). The mean TTR was 41.9% (95% confidence interval [CI], 39.0%-44.8%). Forty-seven (8.3%) and 34 (6.0%) patients had thromboembolic and bleeding events, respectively. Thromboembolic events were associated with a higher proportion of time below the therapeutic range (31.3% vs 19.1%, P = 0.003) and bleeding complications with a higher proportion of time above the therapeutic range (32.5% vs 19.5%, P = 0.006).ConclusionsPatients with CHD who receive VKAs spend < 42% of their time with INR levels in the therapeutic range, with repercussions regarding thromboembolic and bleeding complications.     

Adherence to guidelines for the management of excessive warfarin anticoagulation

Objectives The American College of Chest Physicians (ACCP) provides guidelines for the management of excessive anticoagulation in patients receiving warfarin. This multi-site prospective cohort study evaluated patient-level practice patterns and adherence to ACCP guidelines. Methods Patients presenting with an INR ≥ 4.5 between January 3 and April 29, 2005 were observed and therapeutic management documented. Adherence was assessed retrospectively. Results Four hundred and seventeen patients from 22 centers were observed. The mean, initial INR was 7.7. At enrollment, 85% of the patients had an INR < 9 or were not bleeding; 15% were seriously bleeding. Treatment for 170 patients (41%) did not adhere to guidelines. Among those, 15% were undertreated, 48% overtreated. Lack of adherence was attributed primarily to excessive doses (mean initial dose = 6.9 mg) and inappropriate routes of administration (subcutaneous or intramuscular) of vitamin K1. Conclusion Adherence to the ACCP guidelines is low. Inappropriate use of vitamin K1 is the primary reason.     

The association between tricuspid regurgitation velocity and 5‐year survival in a North West London population of patients with sickle cell disease in the United Kingdom

Raised tricuspid regurgitant velocity (TRV) occurs in approximately 30% of adults with sickle cell disease (SCD), and has been shown to be an independent risk factor for death. TRV was assessed in 164 SCD patients who were subsequently followed up for survival. Raised pulmonary pressures were defined as a TRV jet ≥2·5 m/s on echocardiography. Elevated TRV was present in 29·1% of patients and it was associated with increased age and left atrial diameter. There were 15 deaths (9·1%) over a median of 68·1 months follow up; seven patients had increased TRV, and eight patients had a TRV<2·5 m/s. Higher TRV values were associated with a greater than 4‐fold increased risk of death (Hazard Ratio: 4·48, 99% confidence interval 1·01‐19·8), although we found a lower overall mortality rate than has been reported in previous studies. TRV was not an independent risk factor for death. We have confirmed the association between raised TRV and mortality in a UK SCD population whose disease severity appears to be less than that reported in previous studies. Further prospective studies are needed to more clearly characterize which patient factors modify survival in SCD patients with raised TRV.     

A national study on conditional survival,excess mortality and second cancer after high dose therapy with autologous stem cell transplantation for non‐Hodgkin lymphoma

This national population‐based study aimed to investigate conditional survival and standardized mortality ratios (SMR) after high‐dose therapy with autologous stem‐cell transplantation (HDT‐ASCT) for non‐Hodgkin lymphoma (NHL), and to analyse cause of death, relapses and second malignancies. All patients ≥18 years treated with HDT‐ASCT for NHL in Norway between 1987 and 2008 were included (n = 578). Information from the Cause of Death Registry and Cancer Registry of Norway were linked with clinical data. The 5‐, 10‐ and 20‐year overall survival was 61% (95% confidence interval [CI] 56–64%), 52% (95%CI 48–56%) and 45% (95%CI 40–50%), respectively. The 5‐year survival conditional on having survived 2, 5 and 10 years after HDT‐ASCT was 81%, 86% and 93%. SMRs were 12·3 (95%CI 11·0–13·9), 4·9 (95%CI 4·1–5·9), 2·4 (95%CI 1·8–3·2) and 1·0 (95%CI 0·6–1·8) for the entire cohort and for patients having survived 2, 5 and 10 years after HDT‐ASCT respectively. Of the 281 deaths observed, 77% were relapse‐related. Treatment‐related mortality was 3·6%. The 10‐year cumulative incidence of second malignancies was 7·9% and standardized incidence ratio was 2·0 (95%CI 1·5–2·6). NHL patients treated with HDT‐ASCT were at increased risk of second cancer and premature death. The mortality was still elevated at 5 years, but after 10 years mortality equalled that of the general population.     

Incidence,Source, Determinants,and Prognostic Impact of Major Bleeding in Outpatients With Stable Coronary Artery Disease

Background

Although there is evidence that patients who experience major bleeding after an acute coronary event are at higher risk of death in the months after the event, the incidence and impact on outcome of bleeding beyond 1 year of follow-up in patients with stable coronary artery disease (CAD) are largely unknown.

Objectives

The goal of this study was to assess the incidence, source, determinants, and prognostic impact of major bleeding in stable CAD.

Methods

We prospectively included 4,184 consecutive CAD outpatients who were free from any myocardial infarction (MI) or coronary revascularization for >1 year at inclusion. Follow-up was performed at 2 years, with major bleeding defined as a type ≥3 bleed using the Bleeding Academic Research Consortium (BARC) definition.

Results

There were 51 major bleeding events during follow-up (0.6%/year). Most events were BARC type 3a bleeds with 12 fatal bleeds (type 5). In most cases (54.9%), the site of bleeding was gastrointestinal. Major bleeding was significantly associated with mortality (adjusted hazard ratio: 2.89; 95% confidence intervals: 1.73 to 4.83; p < 0.0001). The increased risk of bleeding associated with vitamin K antagonist (VKA) treatment was particularly evident when VKA was combined with an antiplatelet therapy (APT). In contrast, the risk of cardiovascular death, MI, or nonhemorrhagic stroke did not differ in patients who received VKA + APT versus patients on VKA alone.

Conclusions

In patients with stable CAD (i.e., >1 year, with no acute events), major bleeding events are rare, but such events are an independent predictor of death. When oral anticoagulation is required, concomitant APT should not be prescribed in the absence of a recent cardiovascular event.     

Predictors of anticoagulation quality in 15 834 patients performing patient self‐management of oral anticoagulation with vitamin K antagonists in real‐life practice: a survey of the International Self‐Monitoring Association of Orally Anticoagulated Patients

Although patient self‐management (PSM) of oral anticoagulation with vitamin K antagonists is recommended for patients requiring long‐term anticoagulation, important aspects are still unclear. Using data from a large international survey (n = 15 834; median age 72 years; 30·1% female), we studied predictors of poor anticoagulation control (percentage of International Normalized Ratio values within therapeutic range below 75%) and developed a simple prediction model. The following variables were identified as risk factors for poor anticoagulation control and included in the final model: higher intensity of therapeutic range (odds ratio [OR] on every level 1·9; 95% confidence interval [CI] 1·8–2·0), long intervals between measurements (>14 d; 1·5; 95% CI 1·3–1·7), female sex (OR 1·3; 95% CI 1·2–1·4), and management other than PSM (OR 1·4; 95% CI 1·2–1·6). At a threshold of 0·2 (at least one variable present), the model predicted poor anticoagulation control with a sensitivity of 85·3% (95% CI: 84·0, 86·4) and a specificity of 28·5% (27·6, 29·5). The area under the receiver operated characteristic curve was 0·65. Using the proposed prediction model, physicians will be able to identify patients with a low chance of performing well, considering additional training, regular follow‐up, or adjustment of therapeutic ranges.     

Oral anticoagulation doesn't increase hemorrhagic risk in patients undergoing a cardiac pacemaker or defibrillator implantation

Objectives

This study was designed to assess the hypothesis that the implantation or the replacement of a cardiac stimulator or defibrillator in patients receiving oral anticoagulants with an INR ≥ 2 doesn’t increase the hemorrhagic risk in comparison with patients for whom the treatment has been interrupted temporarily (INR < 2) or with patients not receiving anticoagulants (control group).

Patients and results

We performed a retrospective chart review of bleeding complications in all patients undergoing pacemaker or ICD implantation or replacement between January 2007 and may 2009. In this cohort, 43 patients (10%) were implanted with an INR ≥ 2 while 36 patients (8%) were implanted with an INR < 2 and 352 patients (82%) didn’t receive anticoagulants. No complication (0/36) has been observed in patients having an INR < 2, while 3/43 (7%) complications have been observed in patients with an INR ≥ 2 and 13/352 (3.7%) in patients in the control group (p = 0.3093). Duration of the hospital stay was similar in the three groups: 6.2 days in patients with an INR < 2, 6.8 days in the group with an INR ≥ 2 and 6.2 days in the control group (p = 0.686).

Conclusion

Pacemaker and ICD implantation or replacement without withdrawing of oral anticoagulants and an INR ≥ 2 was not associated with an increase of the hemorrhagic risk.     

Institutional Variability in Patient Radiation Doses ≥5 Gy During Percutaneous Coronary Intervention

ObjectivesThe aim of this study was to evaluate institutional variability in high radiation doses during percutaneous coronary intervention (PCI).BackgroundIt is unknown whether radiation safety practices are optimally applied across institutions performing PCI.MethodsUsing data from a large statewide registry, PCI discharges between July 1, 2016, and March 31, 2018, with a procedural air kerma (AK) recorded were analyzed. PCI procedures were grouped by the performing hospital, and institutional frequency of procedural AK ≥5 Gy was calculated. Fitted hierarchical Bayesian modeling was performed to identify variables independently associated with an AK ≥5 Gy. The performing hospital was included as a random effect in the hierarchical model.ResultsAmong 36,201 PCI procedures at 28 hospitals, procedural AK was ≥5 Gy in 1,477 cases (4.1%), ≥10 Gy in 185 (0.5%), and ≥15 Gy in 105 (0.3%). The institutional frequency of procedural AK ≥5 Gy ranged from 0.0% to 10.9%. Bayesian modeling identified body mass index, dyslipidemia, diabetes, prior coronary bypass surgery, use of mechanical circulatory support, and the performing hospital as independent predictors of an AK ≥5 Gy. The median odds ratio for the performing hospital, representing an estimate of the contribution of interhospital variability in determining the odds of having a procedural AK ≥5 Gy, was 3.08 (95% confidence interval: 3.01 to 3.16).ConclusionsWide variability exists in the institutional frequency of procedural AK ≥5 Gy during PCI. After accounting for patient characteristics and procedural variables, the performing hospital appears to be a major factor in determining patient radiation dose in contemporary PCI.