Faculty Bibliography

OBJECTIVES/OBJECTIVE:Investigation of novel vertical radiation shield (VRS) in reducing operator radiation exposure. BACKGROUND:Radiation exposure to the operator remains an occupational health hazard in the cardiac catheterization laboratory (CCL). METHODS:A mannequin simulating an operator was placed near a computational phantom, simulating a patient. Measurement of dose equivalent and Air Kerma located the angle with the highest radiation, followed by a common magnification (8 in.) and comparison of horizontal radiation absorbing pads (HRAP) with or without VRS with two different: CCL, phantoms, and dosimeters. Physician exposure was subsequently measured prospectively with or without VRS during clinical procedures. RESULTS:Dose equivalent and Air Kerma to the mannequin was highest at left anterior oblique (LAO)-caudal angle (p < .005). Eight-inch magnification increased mGray by 86.5% and μSv/min by 12.2% compared to 10-in. (p < .005). Moving 40 cm from the access site lowered μSv/min by 30% (p < .005). With LAO-caudal angle and 8-in. magnification, VRS reduced μSv/min by 59%, (p < .005) in one CCL and μSv by 100% (p = .016) in second CCL in addition to HRAP. Prospective study of 177 procedures with HRAP, found VRS lowered μSv by 41.9% (μSv: 15.2 ± 13.4 vs. 26.2 ± 31.4, p = .001) with no difference in mGray. The difference was significant after multivariate adjustment for specified variables (p < .001). CONCLUSIONS:Operator radiation exposure is significantly reduced utilizing a novel VRS, HRAP, and distance from the X-ray tube, and consideration of lower magnification and avoiding LAO-caudal angles to lower radiation for both operator and patient.

BACKGROUND:Stroke represents a potentially calamitous complication among patients with acute coronary syndrome (ACS) undergoing percutaneous intervention (PCI). Data on the distribution of stroke occurrence post-PCI and its impact on mortality are scarce. OBJECTIVES/OBJECTIVE:We sought to determine the incidence, predictors and impact of stroke on mortality in ACS patients undergoing PCI. METHODS:A total of 19,914 ACS patients underwent PCI in the PROMETHEUS multicenter observational study. We calculated the cumulative stroke incidence at 30 days and 1 year using the Kaplan Meier method. We also compared the distribution of stroke, myocardial infarction (MI), and bleeding across time and evaluated their overlap. Predictors of stroke were identified through multivariable Cox-regression. Stroke, MI, and bleeding were assessed as time-updated covariates to estimate how each impacts subsequent mortality. RESULTS:We found that 244 patients had a stroke within 1 year, a cumulative incidence of 1.5%. Previous cerebrovascular disease was the strongest predictor for post-PCI stroke, followed by ST-elevation MI presentation, hypertension, non-ST-elevation MI presentation, smoking, female sex, and age. Mortality risk was significantly higher among those who had a stroke versus those who did not (adjusted HR 4.84, p < .0001). However, the association attenuated over time with a much larger effect in the first 30 days of its occurrence (adjusted HR 17.7; 95% CI: 12.3-25.4, p < .0001) versus beyond 30 days (adjusted HR 1.22; 95% CI: 0.6-2.46, p = .58). CONCLUSIONS:Stroke occurrence within 1 year was not uncommon for ACS patients undergoing PCI. When compared with MI and bleeding, stroke had a substantial impact on mortality that attenuated rapidly over time.

Importance:Anatomical scoring systems for coronary artery disease, such as the SYNTAX (Synergy Between Percutaneous Coronary Intervention [PCI] With Taxus and Cardiac Surgery) score, are well established tools for understanding patient risk. However, they are cumbersome to compute manually for large data sets, limiting their use across broad and varied cohorts. Objective:To adapt an anatomical scoring system for use with registry data, allowing facile and automatic calculation of scores and association with clinical outcomes among patients undergoing percutaneous or surgical revascularization. Design, Setting, and Participants:This cross-sectional observational cohort study involved procedures performed in all cardiac catheterization laboratories in the largest integrated health care system in the United States, the Veterans Affairs (VA) Healthcare System. Patients undergoing coronary angiography in the VA Healthcare System followed by percutaneous or surgical revascularization within 90 days were observed and data were analyzed from January 1, 2010, through September 30, 2017. Main Outcomes and Measures:An anatomical scoring system for coronary artery disease complexity before revascularization was simplified and adapted to data from the VA Clinical Assessment, Reporting, and Tracking Program. The adjusted association between quantified anatomical complexity and major adverse cardiovascular and cerebrovascular events (MACCEs), including death, myocardial infarction, stroke, and repeat revascularization, was assessed for patients undergoing percutaneous or surgical revascularization. Results:A total of 50 226 patients (49 359 men [98.3%]; mean [SD] age, 66 [9] years) underwent revascularization during the study period, with 34 322 undergoing PCI and 15 904 undergoing coronary artery bypass grafting (CABG). After adjustment, the highest tertile of anatomical complexity was associated with increased hazard of MACCEs (adjusted hazard ratio [HR], 2.12; 95% CI, 2.01-2.23). In contrast, the highest tertile of anatomical complexity among patients undergoing CABG was not independently associated with overall MACCEs (adjusted HR, 1.04; 95% CI, 0.92-1.17), and only repeat revascularization was associated with increasing complexity (adjusted HR, 1.34; 95% CI, 1.06-1.70) in this subgroup. Conclusions and Relevance:These findings suggest that an automatically computed score assessing anatomical complexity can be used to assess longitudinal risk for patients undergoing revascularization. This simplified scoring system appears to be an alternative tool for understanding longitudinal risk across large data sets.

BACKGROUND:Available data suggest that same-day discharge (SDD) after elective percutaneous coronary intervention (PCI) is safe in select patients. Yet, little is known about contemporary adoption rates, safety, and costs in a universal health care system like the Veterans Affairs Health System. METHODS:Using data from the Veterans Affairs Clinical Assessment Reporting and Tracking Program linked with Health Economics Resource Center data, patients undergoing elective PCI for stable angina between October 1, 2007 and Sepetember 30, 2016, were stratified by SDD versus overnight stay. We examined trends of SDD, and using 2:1 propensity matching, we assessed 30-day rates of readmission, mortality, and total costs at 30 days. RESULTS:Of 21,261 PCIs from 67 sites, 728 were SDDs (3.9% of overall cohort). The rate of SDD increased from 1.6% in 2008 to 9.7% in 2016 (P < .001). SDD patients had lower rates of atrial fibrillation, peripheral arterial disease, and prior coronary artery bypass grafting and were treated at higher-volume centers. Thirty-day readmission and mortality did not differ significantly between the groups (readmission: 6.7% SDD vs 5.6% for overnight stay, P = .24; mortality: 0% vs. 0.07%, P = .99). The mean (SD) 30-day cost accrued by patients undergoing SDD was $23,656 ($15,480) versus $25,878 ($17,480) for an overnight stay. The accumulated median cost savings for SDD was $1503 (95% CI $738-$2,250). CONCLUSIONS:Veterans Affairs Health System has increasingly adopted SDD for elective PCI procedures, and this is associated with cost savings without an increase in readmission or mortality. Greater adoption has the potential to reduce costs without increasing adverse outcomes.

BACKGROUND:Advances in chronic total occlusion percutaneous coronary intervention (CTO PCI) techniques have led to increased procedural success rates among operators. While utilization of CTO PCI has disseminated widely, the learning curve for new operators has not been well-defined. METHODS:Between July 2009 and December 2015, 93 875 CTO PCI cases were extracted from the CathPCI Registry. We delineated a cohort of new CTO operators performing <10 CTO PCI cases per given year. In-hospital outcomes for subsequent CTO PCIs were stratified by the number of prior cases accrued by each operator. Multivariable regression models were used to estimate differences in outcomes with increasing experience. The primary outcome was major adverse cardiovascular events defined as the composite of death, myocardial infarction, stroke, tamponade, or urgent coronary artery bypass grafting. RESULTS:Among 70 916 cases performed by 7251 new operators, procedure success rate was 61.4% and major adverse cardiovascular event rate was 4.2%. Meanwhile, the rate of major bleeding was 4.0%, myocardial infarction 2.0%, mortality 0.6%, tamponade 0.3%, and renal failure 0.2%. Adjusted regression models demonstrated piecewise linear improvements in guidewire crossing, stent placement, and procedure success with accrued volume, albeit with increased contrast use, fluoroscopy time, and bleeding. Major adverse cardiovascular event rates were stable beyond the 12th case (odds ratio per 5 case increase 1.00; 95% CI, 0.98-1.03, P=0.7980). CONCLUSIONS:Among a large number of new CTO PCI operators in the United States, there exists an experiential learning curve for procedural success. However, there were higher rates of bleeding despite case experience, while major adverse cardiovascular events remained relatively unchanged after initiation.