Cause and preventability of in-hospital mortality after PCI: A statewide root-cause analysis of 1,163 deaths.

BACKGROUND: Mortality is the most devastating complication of percutaneous coronary interventions (PCI). Identifying the most common causes and mechanisms of death after PCI in contemporary practice is an important step in further reducing periprocedural mortality. OBJECTIVES: To systematically analyze the cause and circumstances of in-hospital mortality in a large, multi-center, statewide cohort. METHODS: In-hospital deaths after PCI occurring at 39 hospitals included in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) between 2012 and 2014 were retrospectively reviewed using validated methods. A priori PCI-related mortality risk was estimated using the validated BMC2 model. RESULTS: A total of 1,163 deaths after PCI were included in the study. Mean age was 71±13 years, and 507 (44%) were women. Left ventricular failure was the most common cause of death (52% of cases). The circumstance of death was most commonly related to prior acute cardiovascular condition (61% of cases). Procedural complications were considered contributing to mortality in 235 (20%) cases. Death was rated as not preventable or slightly preventable in 1,045 (89.9%) cases. The majority of the deaths occurred in intermediate or high-risk patients, but 328 (28.2%) deaths occurred in low-risk patients (<5% predicted risk of mortality). PCI was considered rarely appropriate in 30% of preventable deaths. CONCLUSIONS: In-hospital mortality after PCI is rare, and primarily related to pre-existing critical acute cardiovascular condition. However, approximately 10% of deaths were preventable. Further research is needed to characterize preventable deaths, in order to develop strategies to improve procedural safety.

Statewide Initiative to Reduce Patient Radiation Doses During Percutaneous Coronary Intervention.

BACKGROUND: Improved radiation safety practices are needed across hospitals performing percutaneous coronary intervention (PCI). This study was performed to assess the temporal trend in PCI radiation doses concurrent with the conduct of a statewide radiation safety initiative. METHODS: A statewide initiative to reduce PCI radiation doses was conducted in Michigan between 2017 and 2021 and included focused radiation safety education, reporting of institutional radiation doses, and implementation of radiation performance metrics for hospitals. Using data from a large statewide registry, PCI discharges between July 1, 2016, and July 1, 2022, having a procedural air kerma (AK) recorded were analyzed for temporal trends. A multivariable regression analysis was performed to determine whether declines in procedural AK over time were attributable to changes in known predictors of radiation doses. RESULTS: Among 131 619 PCI procedures performed during the study period, a reduction in procedural AK was observed over time, from a median dose of 1.46 (0.86-2.37) Gy in the first year of the study to 0.97 (0.56-1.64) Gy in the last year of the study (P<0.001). The proportion of cases with an AK ≥5 Gy declined from 4.24% to 0.86% over the same time period (P<0.0001). After adjusting for variables known to impact radiation doses, a 1-year increase in the date of PCI was associated with a 7.61% (95% CI, 7.38%-7.84%) reduction in procedural AK (P<0.0001). CONCLUSIONS: Concurrent with the conduct of a statewide initiative to reduce procedural radiation doses, a progressive and significant decline in procedural radiation doses was observed among patients undergoing PCI in the state of Michigan.

Merging machine learning and patient preference: a novel tool for risk prediction of percutaneous coronary interventions.

BACKGROUND AND AIMS: Predicting personalized risk for adverse events following percutaneous coronary intervention (PCI) remains critical in weighing treatment options, employing risk mitigation strategies, and enhancing shared decision-making. This study aimed to employ machine learning models using pre-procedural variables to accurately predict common post-PCI complications. METHODS: A group of 66 adults underwent a semiquantitative survey assessing a preferred list of outcomes and model display. The machine learning cohort included 107 793 patients undergoing PCI procedures performed at 48 hospitals in Michigan between 1 April 2018 and 31 December 2021 in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) registry separated into training and validation cohorts. External validation was conducted in the Cardiac Care Outcomes Assessment Program database of 56 583 procedures in 33 hospitals in Washington. RESULTS: Overall rate of in-hospital mortality was 1.85% (n = 1999), acute kidney injury 2.51% (n = 2519), new-onset dialysis 0.44% (n = 462), stroke 0.41% (n = 447), major bleeding 0.89% (n = 942), and transfusion 2.41% (n = 2592). The model demonstrated robust discrimination and calibration for mortality {area under the receiver-operating characteristic curve [AUC]: 0.930 [95% confidence interval (CI) 0.920-0.940]}, acute kidney injury [AUC: 0.893 (95% CI 0.883-0.903)], dialysis [AUC: 0.951 (95% CI 0.939-0.964)], stroke [AUC: 0.751 (95%CI 0.714-0.787)], transfusion [AUC: 0.917 (95% CI 0.907-0.925)], and major bleeding [AUC: 0.887 (95% CI 0.870-0.905)]. Similar discrimination was noted in the external validation population. Survey subjects preferred a comprehensive list of individually reported post-procedure outcomes. CONCLUSIONS: Using common pre-procedural risk factors, the BMC2 machine learning models accurately predict post-PCI outcomes. Utilizing patient feedback, the BMC2 models employ a patient-centred tool to clearly display risks to patients and providers (https://shiny.bmc2.org/pci-prediction/). Enhanced risk prediction prior to PCI could help inform treatment selection and shared decision-making discussions.

A Practical Approach to Preventing Contrast-Associated Renal Complications in the Catheterization Laboratory.

Contrast media use is ubiquitous in the catheterization laboratory. Contrast-associated acute kidney injury (CA-AKI) is a key concern among patients undergoing coronary angiography and percutaneous coronary interventions. The risk of CA-AKI can be minimized by careful attention to hydration status and renal function-based contrast dosing in all patients. In patients with Stage IV chronic kidney disease, ultra low contrast procedure (contrast dose ≤ GFR) may be especially beneficial.

Electroplating a miniature diamond wheel for grinding of the calcified plaque inside arteries.

A miniature grinding wheel (0.85 mm diameter) was fabricated by nickel (Ni)-diamond electroplating on a thin (0.65 mm outer diameter) flexible hollow stainless steel drive shaft to remove the calcified plaque in coronary and peripheral arteries by atherectomy procedure. To coat electrically nonconductive diamond grits, the drive shaft was submerged in a pile of diamond grit during Ni electroplating. The electroplating current density and temperature were investigated for better surface finishing and Faraday efficiency. The electroplating time to obtain the designed coating thickness was modeled based on Faraday's law of electrolysis and the geometry of drive shaft, wheel, and diamond grit. To validate the miniature wheel performance in atherectomy, grinding experiments were conducted on an atherectomy cardiovascular simulator with a calcified plaque surrogate. The wheel motion, material removal rate, and wheel surface wear were studied via high-speed camera imaging and laser confocal microscopy. The grinding wheel with 80,000 rpm rotational speed had an orbital speed of 14,300 rpm around the 1.5 mm diameter plaque surrogate lumen. After grinding for 120 s, the plaque surrogate inner diameter was enlarged to 3.03 mm, and no wear or loss of diamond abrasive was observed on the grinding wheel. This study demonstrated that the proposed electroplating process for fabricating miniature grinding wheels could effectively remove the calcified plaque surrogate. This research could lead to a more effective and safer atherectomy device with sub-mm miniature diamond wheels to treat lesions deep in coronary and peripheral arteries.

Comparative analysis of percutaneous revascularization practice in the United States and the United Kingdom: Insights from the BMC2 and BCIS databases.

BACKGROUND: International registry comparisons provide insight into regional differences in clinical practice patterns, procedural outcomes, and general trends in population health and resource utilization in percutaneous coronary intervention (PCI). We sought to compare data from a state-wide PCI registry in the United States with a national registry from the United Kingdom (UK). METHODS: We analyzed all PCI cases from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium and the British Cardiovascular Intervention Society registries from 2010 to 2017. Procedural characteristics and in-hospital outcomes were stratified by PCI indication. RESULTS: A total of 248,283 cases were performed in Michigan and 773,083 in the United Kingdom during the study period. The proportion of patients with a prior diagnosis of diabetes in Michigan was nearly double that in the United Kingdom (38.9% vs. 21.0%). PCI for ST-elevation myocardial infarction was more frequent in the UK (25% UK vs. 14.3% Michigan). Radial access increased in both registries, reaching 86.8% in the United Kingdom versus 45.1% in Michigan during the final study year. Mechanical support utilization was divergent, falling to 0.9% of cases in the United Kingdom and rising to 3.95% of cases in Michigan in 2017. Unadjusted crude mortality rates were similar in the two cohorts, with higher rates of post-PCI transfusion and other complications in the Michigan population. CONCLUSIONS: In a real-world comparison using PCI registries from the US and UK, notable findings include marked differences in the prevalence of diabetes and other comorbidities, a greater proportion of primary PCI with more robust adoption of transradial PCI in the United Kingdom, and divergent trends in mechanical support with increasing use in Michigan.

Pulsatile Intravascular Lithotripsy: A Novel Mechanism for Peripheral Artery Calcium Fragmentation and Luminal Expansion.

OBJECTIVE: To assess the feasibility and treatment effect of pulsatile intravascular lithotripsy (PIVL) on calcified lesions in a cadaveric model of peripheral artery disease. BACKGROUND: PIVL represents a novel potential approach to intravascular lithotripsy for the treatment of vascular calcification. METHODS: In this preclinical device-feasibility study, technical success, calcium morphology and luminal expansion before and after PIVL treatment were evaluated in surgically isolated, perfused atherosclerotic lower-leg arteries and in perfused whole cadaveric lower legs. Analytical methods included micro-computed tomography (µCT), intravascular optical coherence tomography, digital subtraction angiography, and quantitative coronary analysis. RESULTS: Treatment delivery was successful in all whole-leg specimens (N = 6; mean age 74.2, 66 % female) and in the 8 excised vessels with diameter appropriate to the PIVL balloon (2 vessels exceeding diameter specifications were excluded). There were no vessel perforations. After PIVL, excised vessels showed extensive evidence of new, full-thickness fractures in lesions with calcium arc exceeding 152° and with calcium wall thickness between 0.24 mm and 1.42 mm. PIVL fractures were observed in intimal nodules, sheets, shingles, and medial plates. Vessels within whole-leg specimens also showed full-thickness fracturing and a mean of 1.9 ± 0.9 mm in acute luminal gain, 101.6 ± 99.5 % gain in total minimum cross-sectional area, and a 31.7 ± 13.4 % relative reduction in stenosis (P < 0.001 for all analyses). CONCLUSIONS: In a cadaveric model, PIVL treatment was technically feasible, fractured both circumferential and eccentric calcium lesions, and resulted in acute luminal gain. A clinical feasibility study of PIVL is currently enrolling.

Rates of Intracoronary Imaging Optimization in Contemporary Percutaneous Coronary Intervention: A Report From the BMC2 Registry.

BACKGROUND: Intracoronary imaging (ICI) during percutaneous coronary intervention (PCI) improves outcomes, yet hospital- and physician-level variabilities in ICI and its impact on ICI use in contemporary PCI remain unknown. This study was performed to evaluate hospital- and physician-level use of ICI to optimize PCI. METHODS: Using data from a large statewide registry, patients undergoing PCI between July 2019 and March 2021 were studied. The primary measure of interest was ICI (intravascular ultrasound or optical coherence tomography) optimization during PCI. A fitted hierarchical Bayesian model identified variables independently associated with ICI optimization. The performing hospital and physician were included as random effects in the model. RESULTS: Among 48 872 PCIs, ICI optimization was performed in 8094 (16.6%). Median [interquartile range] hospital- and physician-level frequencies of ICI were 8.8% [3.1%, 16.0%] and 6.1% [1.1%, 25.0%], respectively. Bayesian modeling identified left main PCI (adjusted odds ratio [aOR], 4.41; 95% credible interval [3.82, 5.10]), proximal left anterior descending artery PCI (aOR, 2.28 [2.00, 2.59]), PCI for in-stent restenosis (aOR, 1.55 [1.40, 1.72]), and surgical consult prior to PCI (aOR, 1.21 [1.07, 1.37]) as independent predictors of ICI optimization. The hospital-level median odds ratio, an estimate of the contribution of inter-hospital variability in odds of ICI use, was 3.48 (2.64, 5.04). Physician-level median odds ratio was 3.81 (3.33, 4.45). CONCLUSIONS: Substantial hospital- and physician-level variation in ICI was observed. Except for performance of left main PCI, the hospital and physician performing the PCI were more strongly associated with ICI optimization than any patient or procedural factors.

Impact of Left Ventricular End-Diastolic Pressure on the Outcomes of Patients Undergoing Percutaneous Coronary Intervention.

Left ventricular end-diastolic pressure (LVEDP) is an important hemodynamic marker of left ventricular performance and affects coronary perfusion. We evaluated the association of LVEDP with patient outcomes after elective or urgent percutaneous coronary intervention (PCI). We included n = 49,600 patients undergoing elective or urgent PCI. Patients were divided according to LVEDP tertile for descriptive analysis. The primary end point was in-hospital mortality. A recursive partitioning tree model for mortality was built to guide decision-making in patients with high LVEDP undergoing nonemergent PCI. Overall, n = 18,099 patients had an LVEDP <13 mm Hg, n = 15,416 had an LVEDP 13 to 18 mm Hg, and n = 16,085 had an LVEDP >18 mm Hg. Patients in the high LVEDP tertile had a worse clinical and angiographic/procedural profile and experienced a higher incidence of in-hospital post-PCI adverse outcomes, including death (LVEDP <13 mm Hg 0.3% vs LVEDP 13 to 18 mm Hg 0.4% vs LVEDP >18 mm Hg 0.8%, p <0.001). An elevated LVEDP was an independent predictor of adverse outcomes including mortality. An LVEDP ≥26 mm Hg was identified as a marker of high mortality (1.5%) in patients who underwent elective PCI, with rates varying from 0.5% to 10.4%, based upon a clinical profile defined by hemoglobin, systolic blood pressure, renal and left ventricular function, and atrial fibrillation. In conclusion, an elevated LVEDP is observed in 1/3 of the patients who underwent elective or urgent PCI and is associated with higher rates of in-hospital adverse outcomes, including death. Patients with an LVEDP ≥26 mm Hg who underwent elective PCI had markedly higher mortality rates, suggesting that such patients may warrant further optimization before PCI.

Trends and outcomes of percutaneous coronary intervention during the COVID-19 pandemic in Michigan.

BACKGROUND: The COVID-19 pandemic has severely impacted healthcare delivery and patient outcomes globally. AIMS: We aimed to evaluate the influence of the COVID-19 pandemic on the temporal trends and outcomes of patients undergoing percutaneous coronary intervention (PCI) in Michigan. METHODS: We compared all patients undergoing PCI in the BMC2 Registry between March and December 2020 ("pandemic cohort") with those undergoing PCI between March and December 2019 ("pre-pandemic cohort"). A risk-adjusted analysis of in-hospital outcomes was performed between the pre-pandemic and pandemic cohort. A subgroup analysis was performed comparing COVID-19 positive vs. negative patients during the pandemic. RESULTS: There was a 15.2% reduction in overall PCI volume from the pre-pandemic (n = 25,737) to the pandemic cohort (n = 21,822), which was more pronounced for stable angina and non-ST-elevation acute coronary syndromes (ACS) presentations, and between February and May 2020. Patients in the two cohorts had similar clinical and procedural characteristics. Monthly mortality rates for primary PCI were generally higher in the pandemic period. There were no significant system delays in care between the cohorts. Risk-adjusted mortality was higher in the pandemic cohort (aOR 1.26, 95% CI 1.07-1.47, p = 0.005), a finding that was only partially explained by worse outcomes in COVID-19 patients and was more pronounced in subjects with ACS. During the pandemic, COVID-19 positive patients suffered higher risk-adjusted mortality (aOR 5.69, 95% CI 2.54-12.74, p<0.001) compared with COVID negative patients. CONCLUSIONS: During the COVID-19 pandemic, we observed a reduction in PCI volumes and higher risk-adjusted mortality. COVID-19 positive patients experienced significantly worse outcomes.

In-Hospital Death Among Patients Undergoing Percutaneous Coronary Intervention: A Root-Cause Analysis.

BACKGROUND: Mortality related to percutaneous coronary intervention (PCI) has gradually declined during the last decade. However, the causes and circumstances of death remain largely undescribed in contemporary practice. METHODS: We retrospectively evaluated all patients undergoing PCI at our institution from July 2013 to March 2021. Three cardiologists independently determined the causes and circumstances of death, and evaluated the preventability of death using validated methods. RESULTS: During study period, 4334 patients underwent 5506 PCIs, of whom 166 patients suffered in-hospital death (3.0%). Ninety-three percent of deceased patients initially presented with acute coronary syndrome, and 45% with cardiogenic shock. Left ventricular failure was the most common cause of death (39.7%), followed by neurologic compromise after cardiac arrest (16.8%) and infections (13.8%). The circumstance of death was most commonly acute cardiac (51.8%), followed by non-cardiac (19.2%) and non-procedural complications (17.4%). Death was attributed to a procedural complication in only 12% of cases. Reviewers determined that 90% of cases as being unpreventable or slightly preventable. Inter-reviewer agreement was substantial (the three reviewers agreed in >80% of cases for cause and preventability of death). CONCLUSION: Mortality after PCI is uncommon, largely unpreventable, and most often related to pre-existing, acute cardiovascular conditions. Procedural complications account for a minority of cases of death, and future effort should focus on the treatment of acute cardiovascular conditions, in particular cardiogenic shock, to decrease acute mortality after PCI.

Hospital and Operator Variation in Cardiac Rehabilitation Referral and Participation After Percutaneous Coronary Intervention: Insights From Blue Cross Blue Shield of Michigan Cardiovascular Consortium.

BACKGROUND: Despite its established benefit and strong endorsement in international guidelines, cardiac rehabilitation (CR) use remains low. Identifying determinants of CR referral and use may help develop targeted policies and quality improvement efforts. We evaluated the variation in CR referral and use across percutaneous coronary intervention (PCI) hospitals and operators. METHODS: We performed a retrospective observational cohort study of all patients who underwent PCI at 48 nonfederal Michigan hospitals between January 1, 2012 and March 31, 2018 and who had their PCI clinical registry record linked to administrative claims data. The primary outcomes included in-hospital CR referral and CR participation, defined as at least one outpatient CR visit within 90 days of discharge. Bayesian hierarchical regression models were fit to evaluate the association between PCI hospital and operator with CR referral and use after adjusting for patient characteristics. RESULTS: Among 54 217 patients who underwent PCI, 76.3% received an in-hospital referral for CR, and 27.1% attended CR within 90 days after discharge. There was significant hospital and operator level variation in in-hospital CR referral with median odds ratios of 3.88 (95% credible interval [CI], 3.06-5.42) and 1.64 (95% CI, 1.55-1.75), respectively, and in CR participation with median odds ratios of 1.83 (95% CI, 1.63-2.15) and 1.40 (95% CI, 1.35-1.47), respectively. In-hospital CR referral was significantly associated with an increased likelihood of CR participation (adjusted odds ratio, 1.75 [95% CI, 1.52-2.01]), and this association varied by treating PCI hospital (odds ratio range, 0.92-3.75) and operator (odds ratio range, 1.26-2.82). CONCLUSIONS: In-hospital CR referral and 90-day CR use after PCI varied significantly by hospital and operator. The association of in-hospital CR referral with downstream CR use also varied across hospitals and less so across operators suggesting that specific hospitals and operators may more effectively translate CR referrals into downstream use. Understanding the factors that explain this variation will be critical to developing strategies to improve CR participation overall.

Trends in interventional stroke device utilization during the COVID-19 pandemic.

OBJECTIVES: The collateral effect of the COVID-19 pandemic on interventional stroke care is not well described. We studied this effect by utilizing stroke device sales data as markers of interventional stroke case volume in the United States. METHODS: Using a real-time healthcare device sales registry, this observational study examined trends in the sales of thrombectomy devices and cerebral aneurysm coiling from the same 945 reporting hospitals in the U.S. between January 22 and June 31, 2020, and for the same months in 2018 and 2019 to allow for comparison. We simultaneously reviewed daily reports of new COVID-19 cases. The strength of association between the cumulative incidence of COVID-19 and procedural device sales was measured using Spearman rank correlation coefficient (CC). RESULTS: Device sales decreased for thrombectomy (- 3.7%) and cerebral aneurysm coiling (- 8.5%) when comparing 2019-2020. In 2020, thrombectomy device sales were negatively associated with the cumulative incidence of COVID-19 (CC - 0.56, p < 0.0001), with stronger negative correlation during April (CC - 0.97, p < 0.0001). The same negative correlation was observed with aneurysm treatment devices (CC - 0.60, p < 0.001), with stronger correlation in April (CC - 0.97, p < 0.0001). CONCLUSIONS: The decline in sales of stroke interventional equipment underscores a decline in associated case volumes. Future pandemic responses should consider strategies to mitigate such negative collateral effects.