Neuroprotective effects of lactate and ketone bodies in acute brain injury.

The goal of neurocritical care is to prevent and reverse the pathologic cascades of secondary brain injury by optimizing cerebral blood flow, oxygen supply and substrate delivery. While glucose is an essential energetic substrate for the brain, we frequently observe a strong decrease in glucose delivery and/or a glucose metabolic dysregulation following acute brain injury. In parallel, during the last decades, lactate and ketone bodies have been identified as potential alternative fuels to provide energy to the brain, both under physiological conditions and in case of glucose shortage. They are now viewed as integral parts of brain metabolism. In addition to their energetic role, experimental evidence also supports their neuroprotective properties after acute brain injury, regulating in particular intracranial pressure control, decreasing ischemic volume, and leading to an improvement in cognitive functions as well as survival. In this review, we present preclinical and clinical evidence exploring the mechanisms underlying their neuroprotective effects and identify research priorities for promoting lactate and ketone bodies use in brain injury.

Variations in Autoregulation-Based Optimal Cerebral Perfusion Pressure Determination Using Two Integrated Neuromonitoring Platforms in a Trauma Patient.

BACKGROUND: Neuromonitoring devices are often used in traumatic brain injury. The objective of this report is to raise awareness concerning variations in optimal cerebral perfusion pressure (CPPopt) determination using exploratory information provided by two neuromonitoring monitors that are part of research programs (Moberg CNS Monitor and RAUMED NeuroSmart LogO). METHODS: We connected both monitors simultaneously to a parenchymal intracranial pressure catheter and recorded the pressure reactivity index (PRx) and the derived CPPopt estimates for a patient with a severe traumatic brain injury. These estimates were available at the bedside and were updated at each minute. RESULTS: Using the Bland and Altman method, we found a mean variation of - 3.8 (95% confidence internal from - 8.5 to 0.9) mm Hg between the CPPopt estimates provided by the two monitors (limits of agreement from - 26.6 to 19.1 mm Hg). The PRx and CPPopt trends provided by the two monitors were similar over time, but CPPopt trends differed when PRx values were around zero. Also, almost half of the CPPopt estimates differed by more than 10 mm Hg. CONCLUSIONS: These wide variations recorded in the same patient are worrisome and reiterate the importance of understanding and standardizing the methodology and algorithms behind commercial neuromonitoring devices prior to incorporating them in clinical use.

Cerebral Lactate Uptake After Half-Molar Sodium Lactate Therapy in Traumatic Brain Injury: A Brief Report.

Exogenous sodium lactate has many advantages after traumatic brain injury, including intracranial pressure control and alternative energetic supply. It remains unclear, however, whether half-molar sodium lactate (HSL) is effectively incorporated in brain metabolism, which we can verify using the arteriovenous difference in lactate (AVDlac). Hence we compared the AVDlac in patients with severe traumatic brain injury receiving an equiosmolar bolus of sodium lactate or mannitol for intracranial hypertension (IH) treatment. We included 23 patients: 14 received HSL for 25 IH episodes, and nine received mannitol for 19 episodes (total of 44 IH episodes). We observed that the median variation in AVDlac was positive in the group that received HSL (Δ +0.1 [IQR -0.08-0.2] mmol/L), which suggests a net lactate uptake by the brain. On the other hand, it was negative in the group that received mannitol (Δ -0.0 [IQR -0.1 to 0.0] mmol/L), indicating a net lactate export. Finally, there were more positive AVDlac values in the group that received HSL and more negative AVDlac values in the group that received mannitol (Fisher exact p = 0.04). Our study reports the first evidence of a positive AVDlac, which corresponds to a net lactate uptake by the brain, in patients who received HSL for severe TBI. Our results constitute a bedside confirmation of the integration of lactate into the brain metabolism and pave the way for a wider dissemination of sodium lactate in the daily clinical care of patients with traumatic brain injury.

Preoperative fibrinogen level and blood transfusions in liver transplantation: A systematic review.

BACKGROUND: Orthotopic liver transplantation (OLT) is a major surgery often associated with significant bleeding. We conducted a systematic review to explore the association between preoperative fibrinogen level and intraoperative blood products transfusion, blood loss and clinical outcomes in patients undergoing OLT. METHODS: We included observational studies conducted in patients undergoing an OLT mostly for end-stage liver disease that reported an association between the preoperative fibrinogen level and our outcomes of interest. Our primary outcome was the intraoperative red blood cell (RBC) transfusion requirements. Our secondary outcomes were intraoperative blood loss, intraoperative transfusion of any blood product, postoperative RBC transfusion, postoperative thrombotic or hemorrhagic complications, and mortality. We used a standardized search strategy. We reported our results mostly descriptively but conducted meta-analyses using random-effect models when judged feasible. RESULTS: We selected 24 cohort studies reporting at least one of our outcomes. We found that a high preoperative fibrinogen level was associated with fewer intraoperative RBC and other blood products transfusions, and lower blood loss. We also found a lower overall survival in patients with a higher fibrinogen level (pooled hazard ratio [95% CI] of 1.50 [1.23 to 1.84]; 5 studies, n = 1012, I2 = 48%). Only one study formally explored a fibrinogen level threshold effect. Overall, reporting was heterogeneous, and risk of bias was variable mostly because of uncontrolled confounding. CONCLUSION: A higher preoperative fibrinogen level was associated with fewer intraoperative RBC and other blood products transfusions, lower blood loss, and higher mortality. Further studies may help clarify observed associations and inform guidelines.

Infratentorial Brain Injury Among Patients Suspected of Death by Neurologic Criteria: A Systematic Review and Meta-analysis.

BACKGROUND AND OBJECTIVES: There is a paucity of data on the frequency and prognosis of infratentorial brain injury among patients suspected of death by neurologic criteria (DNC), which likely contributes to scientific uncertainty regarding the role of isolated brainstem death in DNC determination. Our aim was to synthesize the prevalence, characteristics, and evolution of infratentorial brain injury, including isolated brainstem death, among patients suspected of DNC. METHODS: We conducted a systematic review by searching Medline, Embase, EBM Reviews, CINAHL Complete, and the gray literature from inception to March 26, 2021. We selected cohort and cross-sectional studies, case reports, and case series that included patients suspected of DNC. Two study investigators independently performed study selection, data collection, and risk of bias assessment. Our primary outcomes were the respective prevalence of infratentorial brain injury and isolated brainstem death, which we meta-analyzed using mixed-effects Bayesian hierarchical models with diffuse priors. Our secondary outcomes were the characteristics and evolution of patients with infratentorial brain injury and isolated brainstem death. RESULTS: Twenty-one studies met the selection criteria, most of which were of moderate to high risk of bias. Among patients suspected of DNC, the prevalence of infratentorial brain injury ranged from 2% to 16% (n = 3,602, mean prevalence: 6.3%, 95% highest density interval [2.4%-14.2%]), whereas the prevalence of isolated brainstem death ranged from 1% to 4% (n = 3,692, mean prevalence: 1.5%, 95% highest density interval [0.5%-3.9%]). A total of 38 isolated brainstem death cases with data on clinical characteristics and/or evolution were included. All had infratentorial strokes. Twenty patients had EEG background activity in the α or θ frequencies, 19 had preserved cerebral blood flow, 2 had preserved supratentorial cerebral perfusion, 2 had cortical responses to visual evoked potentials, and 1 had cortical responses to somatosensory evoked potentials. At the latest follow-up, 28 had progressed to whole-brain death. DISCUSSION: Studies with moderate to high risk of bias suggest that infratentorial brain injury is relatively uncommon among patients suspected of DNC. Isolated brainstem death is rarer and seems to carry a high risk of progression to whole-brain death. These findings require further high-quality investigation.

Association between obesity and hospital mortality in critical COVID-19: a retrospective cohort study.

BACKGROUND: The impact of obesity on outcomes in acute respiratory distress syndrome (ARDS) is not well understood and remains controversial. Recent studies suggest that obesity might be associated with higher morbidity and mortality in respiratory disease caused by SARS-CoV-2 (COVID-19 disease). Our objective was to evaluate the association between obesity and hospital mortality in critical COVID-19 patients. METHODS: We conducted a retrospective cohort study in a tertiary academic center located in Montréal between March and August 2020. We included all consecutive adult patients admitted to the ICU for COVID-19-confirmed respiratory disease. Our main outcome was hospital mortality. We estimated the association between obesity, using the body mass index as a continuous variable, and hospital survival by fitting a multivariable Cox proportional hazards model. RESULTS: We included 94 patients. Median [q1, q3] body mass index (BMI) was 29 [26-32] kg/m2 and 37% of patients were obese (defined as BMI > 30 kg/m2). Hospital mortality for the entire cohort was 33%. BMI was significantly associated with hospital mortality (hazard ratio [HR] = 2.49 per 10 units BMI; 95% CI, from 1.69 to 3.70; p < 0.001) even after adjustment for sex, age and obesity-related comorbidities (adjusted HR = 3.50; 95% CI from 2.03 to 6.02; p < 0.001). CONCLUSIONS: Obesity was prevalent in hospitalized patients with critical illness secondary to COVID-19 disease and a higher BMI was associated with higher hospital mortality. Further studies are needed to validate this association and to better understand its underlying mechanisms.

Feasibility and Safety of Early Repeat Transradial Access Within 30 Days of Previous Coronary Angiography and Intervention.

Transradial approach (TRA) is the default access site for diagnostic angiography and intervention in many centers. Repeat ipsilateral radial artery access late after index procedure has been associated with failures. It is unknown whether early (≤30 days) and very early (<24 hours) repeat radial access is technically feasible and safe. Study population consisted of consecutive patients undergoing repeat (≥2) procedures within 30 days in a high-volume TRA center. Transradial access failure and resulting femoral approach was categorized as primary (no repeat attempt) or secondary (crossover). Timing of repeat access and reasons for failure were recorded. From November 2012 to December 2014, repeat catheterization by TRA was performed twice in 573 of 626 patients (92%) (median delay 4 [2 to 9] days), 3 times in 29 of 38 (76%) patients (median delay 15 [5 to 26] days), and 4 times in 1 patient within 21 days. When repeat catheterization occurred during the first 24 hours following the index procedure, 53% and 75% of patients had second and third procedures using the same ipsilateral radial artery, respectively. Primary radial failure occurred in 5.8% for second attempt and 13% for a third attempt, whereas crossovers were noted in 2.7% and 2.6%, respectively. Main reasons for failed re-access of ipsilateral radial artery were related either to operator's reluctance to repeat attempt (primary failure) or to issues with puncture site (crossover). In a high-volume TRA center, patients who required repeat catheterization within 24 hours and within the first 30 days had the same radial artery re-accessed in the majority of cases.

Comparison of radiation exposure during transradial diagnostic coronary angiography with single- or multi-catheters approach.

OBJECTIVE: To compare radiation exposure during transradial diagnostic coronary angiography (DCA) using standard single- or multi-catheters with different shapes. BACKGROUND: Transradial DCA can be performed using single- or multi-catheters to canulate left and right coronary ostia. To date, it remains unknown whether there are differences in radiation exposure between the two strategies. METHODS: From November 2012 to June 2014, 3,410 consecutive patients who underwent transradial DCA were recruited. Groups were based on the initial diagnostic catheter used and were dichotomized between single- and multi-catheters approach. All crossovers were excluded. The multi-catheters approach (Multi) group consisted of Judkins left and right catheters, whereas the single-catheter (Single) group included Amplatz, Barbeau, or Multipurpose catheters. Fluoroscopy time (FT) as a surrogate end-point for total radiation exposure and kerma-area product (KAP; patient radiation exposure) were collected as radiation exposure parameters. RESULTS: A single-catheter strategy was used in 439 patients, while 2,971 patients had a multi-catheters approach. There was no significant difference in FT between groups (2.86 ± 1.48 min for Multi vs. 2.87 ± 1.72 min for Single, P = 0.13). The multi-catheters approach was associated with a significant 15% reduction in KAP (3,599 ± 2,214 cGy · cm2 vs. 3,073 ± 1,785 cGy · cm2 , P < 0.0001) compared to the single-catheter approach. When pooling all patients, mean FT was 2.86 ± 1.51 min. Mean KAP was 3,141 ± 1,854 cGy · cm2 . Reference levels in our institution in both groups were below international diagnostic reference levels. Overall both FT and KAP decreased by 15% and 19%, respectively, over the 2-year study period. CONCLUSIONS: Compared to a single-catheter approach, a multi-catheters approach with standard Judkins catheters for DCA significantly reduced patient radiation exposure. Whether single catheter designed for DCA by radial approach can further reduce radiation exposure compared to Judkins catheters remains to be compared in randomized studies. © 2016 Wiley Periodicals, Inc.

Prediction and impact of failure of transradial approach for primary percutaneous coronary intervention.

OBJECTIVES: To determine predictors of failure of transradial approach (TRA) in patients with ST elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI), and develop a novel score specific for this population. METHODS: Consecutive patients with STEMI undergoing primary PCI in a tertiary care high-volume radial centre were included. TRA-PCI failure was categorised as primary (primary transfemoral approach (TFA)) or crossover (from TRA to TFA). Multivariate analysis was performed to determine independent predictors of TRA-PCI failure, and an integer risk score was developed. Clinical outcomes up to 1 year were assessed. RESULTS: From January 2006 to January 2011, 2020 patients were studied. Primary TRA-PCI failure occurred in 111 (5%) patients and crossover to TFA in 44 (2.2%) patients. Independent predictors of TRA-PCI failure were: weight ≤65 kg (OR: 3.0; 95% CI 1.9 to 4.8, p<0.0001), physician with ≤5% TFA conversion (OR: 0.45; 95% CI 0.2 to 0.9, p=0.033), and physician with ≥10% conversion to TFA (OR: 2.2; 95% CI 1.2 to 3.7, p=0.005), intra-aortic balloon pump (OR: 2.0; 95% CI 0.9 to 4.3, p=0.066), cardiogenic shock (OR: 2.8; 95% CI 1.4 to 5.6, p=0.0035), endotracheal intubation (OR: 107; 95% CI 42 to 339, p<0.0001), creatinine >133 µmol/L (OR: 3.6; 95% CI 1.9 to 6.8, p<0.0001), age ≥75 (OR: 1.7; 95% CI 1.0 to 2.9, p=0.031), prior PCI (OR: 2.6; 95% CI 1.5 to 4.5, p=0.0009), hypertension (OR: 1.8; 95% CI 1.2 to 2.9, p=0.009). An integer risk score ranging from -1 to 12 was developed, and predicted TRA-PCI failure from 0% to 100% (c-statistic of 0.868; 95% CI 0.866 to 0.869). Mortality at 1 year remained significantly higher after TRA-PCI failure (adjusted OR 2.2; 95% CI 1.2 to 3.9, p=0.011). CONCLUSIONS: In a high-volume radial centre, the incidence of TRA-PCI failure is low and can be accurately predicted using a 9-variables risk score. Since outcomes after TRA-PCI failure remained inferior, further effort to maximise the use of radial approach for primary PCI should be investigated.

Meta-Analysis of Effects of Bivalirudin Versus Heparin on Myocardial Ischemic and Bleeding Outcomes After Percutaneous Coronary Intervention.

Bivalirudin is an alternative to unfractionated heparin (UFH) anticoagulation during percutaneous coronary intervention. Previously, we have reported clinical benefit on major bleeding in favor of bivalirudin compared with UFH monotherapy but inconclusive results on mortality. Controversial data have been reported in the last 2 years. We conducted an updated meta-analysis including randomized trials and observational studies, which evaluated ischemic and bleeding outcomes for bivalirudin compared with UFH-only during percutaneous coronary intervention. We included 18 observational studies and 12 randomized trials published from 2003 to 2015. Primary outcomes were major adverse cardiovascular events within 30 days including death, myocardial infarction, and urgent revascularization and stent thrombosis, major bleeding, and transfusion. Overall, we found a significant risk reduction with bivalirudin for major bleeding (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.49 to 0.71, p <0.0001) and for transfusion (OR 0.79, 95% CI 0.66 to 0.95, p = 0.01) and similar risk for major adverse cardiovascular events (OR 0.98, 95% CI 0.86 to 1.12, p = 0.80). However, there was a substantial increased risk of stent thrombosis associated with bivalirudin (OR 1.52, 95% CI 1.11 to 2.08, p = 0.009). No impact on mortality was found. Meta-regression analyses on major bleeding suggested that bivalirudin was more effective than UFH at doses >60 IU/kg and independent of radial access. In conclusion, compared with UFH monotherapy, bivalirudin remains associated with less bleeding risk but higher stent thrombosis risk. Further study remains required to define its role in current antithrombotic armamentarium.

Efficacy and safety of preoperative intra-aortic balloon pump use in patients undergoing cardiac surgery: a systematic review and meta-analysis.

BACKGROUND: Intra-aortic balloon pump (IABP) can be used prior to coronary artery bypass graft surgery (CABG) in high-risk patients. Whether this technique remains safe and effective in contemporary practice is controversial. OBJECTIVE: We have completed a systematic review and meta-analysis of randomized trials and observational studies to evaluate the safety and benefits of IABP prior to CABG surgery. METHODS: We searched PubMed, EMBASE, Cochrane Library databases, with cross-referencing of relevant articles for studies assessing the impact of IABP prior to and after isolated CABG. Two investigators independently sorted the potentially relevant studies, and three extracted data. The assessed outcomes included in-hospital and 30-day mortality, IABP-related complications and length of intensive care unit and hospital stay. RESULTS: From 1977 to 2015 we included 11 randomized controlled trials (n=1293) (RCTs) and 22 observational studies, including a total of 46,067 patients. Analyses from RCTs suggested that IABP prior to CABG was associated with a significant reduction in hospital mortality (odds ratio (OR) 0.20; 95% confidence interval (CI): 0.09-0.44; P<0.0001) and 30-day mortality compared to no preoperative IABP (OR 0.43, 95% CI: 0.25-0.76; P=0.003). IABP prior to CABG was also associated with shorter intensive care unit (weighted mean difference (WMD) -1.47day; 95% CI: -1.82 to -1.12day; P<0.00001) and hospital length of stay (WMD -3.25days; 95% CI: -5.18 to -1.33days; P=0.0009). However, there were significant bias and limitations among included studies. Furthermore, results for similar outcomes from observational studies remained inconclusive. CONCLUSIONS: In contemporary practice, evidence showing clinical benefit for preoperative IABP in high-risk patients remains limited and requires further validation in an appropriately sized multicenter randomized trial.

Radiation exposure in relation to the arterial access site used for diagnostic coronary angiography and percutaneous coronary intervention: a systematic review and meta-analysis.

BACKGROUND: Transradial access for cardiac catheterisation results in lower bleeding and vascular complications than the traditional transfemoral access route. However, the increased radiation exposure potentially associated with transradial access is a possible drawback of this method. Whether transradial access is associated with a clinically significant increase in radiation exposure that outweighs its benefits is unclear. Our aim was therefore to compare radiation exposure between transradial access and transfemoral access for diagnostic coronary angiograms and percutaneous coronary interventions (PCI). METHODS: We did a systematic review and meta-analysis of the scientific literature by searching the PubMed, Embase, and Cochrane Library databases with relevant terms, and cross-referencing relevant articles for randomised controlled trials (RCTs) that compared radiation parameters in relation to access site, published from Jan 1, 1989, to June 3, 2014. Three investigators independently sorted the potentially relevant studies, and two others extracted data. We focused on the primary radiation outcomes of fluoroscopy time and kerma-area product, and used meta-regression to assess the changes over time. Secondary outcomes were operator radiation exposure and procedural time. We used both fixed-effects and random-effects models with inverse variance weighting for the main analyses, and we did confirmatory analyses for observational studies. FINDINGS: Of 1252 records identified, we obtained data from 24 published RCTs for 19 328 patients. Our primary analyses showed that transradial access was associated with a small but significant increase in fluoroscopy time for diagnostic coronary angiograms (weighted mean difference [WMD], fixed effect: 1·04 min, 95% CI 0·84-1·24; p<0·0001) and PCI (1·15 min, 95% CI 0·96-1·33; p<0·0001), compared with transfemoral access. Transradial access was also associated with higher kerma-area product for diagnostic coronary angiograms (WMD, fixed effect: 1·72 Gy·cm(2), 95% CI -0·10 to 3·55; p=0·06), and significantly higher kerma-area product for PCI (0·55 Gy·cm(2), 95% CI 0·08-1·02; p=0·02). Mean operator radiation doses for PCI with basic protection were 107 µSv (SD 110) with transradial access and 74 µSv (68) with transfemoral access; with supplementary protection, the doses decreased to 21 µSv (17) with transradial access and 46 µSv (9) with transfemoral. Meta-regression analysis showed that the overall difference in fluoroscopy time between the two procedures has decreased significantly by 75% over the past 20 years from 2 min in 1996 to about 30 s in 2014 (p<0·0001). In observational studies, differences and effect sizes remained consistent with RCTs. INTERPRETATION: Transradial access was associated with a small but significant increase in radiation exposure in both diagnostic and interventional procedures compared with transfemoral access. Since differences in radiation exposure narrow over time, the clinical significance of this small increase is uncertain and is unlikely to outweigh the clinical benefits of transradial access. FUNDING: None.

4Fr in 5Fr sheathless technique with standard catheters for transradial coronary interventions: technical challenges and persisting issues.

OBJECTIVES: To evaluate the feasibility and potential benefits of performing sheathless 5Fr transradial percutaneous coronary interventions (PCI) using 4Fr diagnostic catheters as dilators. BACKGROUND: There is a direct association between artery-catheter mismatch and risk of radial artery occlusion. METHODS: We recruited 130 patients who underwent 4Fr sheathless diagnostic angiography with super torque (Cordis Corporation, USA) catheters followed by ad hoc PCI. To facilitate skin and vessel penetration, the Judkins right catheter (110 cm) was inserted inside the 5Fr guiding catheter (100 cm) as dilator. RESULTS: The mean age of patients was 63±12 years with 74% of males. Unfractionated heparin monotherapy was used in 84%, bivalirudin in 12%, and platelet glycoprotein 2b/3a inhibitors in 13%. Right radial artery was used in 99%. In three cases, no PCI was performed (FFR) and in two (1.5%) cases, a sheath was required after guiding catheter insertion due to local bleeding. In six cases (4.6%), upscale to 6Fr sheathed approach was required. No spasm occurred. Overall procedural success was achieved in 114/119 (96%) cases, including left main PCI, bifurcation PCI in 10 (8%) cases, CTO in 5 (4%) and IVUS use in 6 (5%) cases. Immediately after hemostasis completion, duplex ultrasound showed normal flow in 76%, occlusive thrombus in 13%, pseudo-aneurysmal dilatation in 11% and local hematoma surrounding puncture site in 20%. Hemoglobin dropped from 138±19 g/l to 131±16 g/l 4-6 hours after PCI. CONCLUSION: Using 4Fr diagnostic catheters as dilators, simple and complex PCI can be performed with standard 5Fr guiding catheters as sheathless techniques. However, suboptimal transition between diagnostic and guiding catheters likely creates radial artery trauma leading to frequent occlusive thrombus and hematoma surrounding the radial artery.

The Transradial Approach and Antithrombotic Therapy: Rationale and Outcomes.

This article reviews antithrombotic strategies for percutaneous coronary interventions according to the access site and the current evidence with the aim of limiting ischemic complications and preventing radial artery occlusion (RAO). Prevention of RAO should be part of the quality control of any radial program. The incidence of RAO postcatheterization and interventions should be determined initially using the echo-duplex and then frequently assessed using the more cost-effective pulse oximetry technique. Any evidence of higher risk of RAO should prompt internal analysis and multidisciplinary mechanisms to be put in place.

Effectiveness of low rate fluoroscopy at reducing operator and patient radiation dose during transradial coronary angiography and interventions.

OBJECTIVES: This study sought to determine the efficacy of low rate fluoroscopy at 7.5 frames/s (FPS) versus conventional 15 FPS for reduction of operator and patient radiation dose during diagnostic coronary angiography (DCA) and percutaneous coronary intervention (PCI) via the transradial approach (TRA). BACKGROUND: TRA for cardiac catheterization is potentially associated with increased radiation exposure. Low rate fluoroscopy has the potential to reduce radiation exposure. METHODS: Patients undergoing TRA diagnostic angiography ± ad-hoc PCI were randomized to fluoroscopy at 7.5 FPS versus 15 FPS prior to the procedure. Both 7.5 and 15 FPS fluoroscopy protocols were configured with a fixed dose per pulse of 40 nGy. Primary endpoints were operator radiation dose (measured with dosimeter attached to the left side of the thyroid shield in µSievert [µSv]), patient radiation dose (expressed as dose-area product in Gy·cm(2)), and fluoroscopy time. RESULTS: From October 1, 2012 to August 30, 2013, from a total of 363 patients, 184 underwent DCA and 179 underwent PCI. Overall, fluoroscopy at 7.5 FPS compared with 15 FPS was associated with a significant reduction in operator dose (30% relative reduction [RR], p < 0.0001); and in patient's dose-area product (19% RR; p = 0.022). When stratified by procedure type, 7.5 FPS compared with 15 FPS was associated with significant reduction in operator dose during both DCA (40% RR; p < 0.0001) and PCI (28% RR; p = 0.0011). Fluoroscopy at 7.5 FPS, compared with 15 FPS, was also associated with substantial reduction in patients' dose-area product during DCA (26% RR; p = 0.0018) and during PCI (19% RR; p = 0.13). Fluoroscopy time was similar in 7.5 FPS and 15 FPS groups for DCA (3.4 ± 2.0 min vs. 4.0 ± 4.7 min; p = 0.42) and PCI (11.9 ± 8.4 min vs. 13.3 ± 9.7 min; p = 0.57), respectively. CONCLUSIONS: Fluoroscopy at 7.5 FPS, compared with 15 FPS, is a simple and effective method in reducing operator and patient radiation dose during TRA DCA and PCI.