Determinants of radiation dose during right transradial access: Insights from the RAD-MATRIX study.

BACKGROUND: The RAD-MATRIX trial reported a large operator radiation exposure variability in right radial percutaneous coronary procedures. The reasons of these differences are not well understood. Our aim was to appraise the determinants of operator radiation exposure during coronary right transradial procedures. METHODS: Patient arrangement during transradial intervention was investigated across operators involved in the RAD-MATRIX trial. Operator radiation exposure was analyzed according to the position of the patient right arm (close or far from the body) and in relation to the size of the upper leaded glass. RESULTS: Among the 14 operators who agreed to participate, there was a greater than 10-fold difference in radiation dose at thorax level (from 21.5 to 267 µSv) that persisted after normalization by dose-area product (from 0.35 to 3.5 µSv/Gy*cm2). Among the operators who positioned the instrumented right arm far from the body (110.4 µSv, interquartile range 71.5-146.5 µSv), thorax dose was greater than that in those who placed the instrumented arm close to the right leg (46.1 µSv, 31.3-56.8 µSv, P = .02). This difference persisted after normalization by dose-area product (P = .028). The use of a smaller full glass shield was also associated with a higher radiation exposure compared with a larger composite shield (147.5 and 60 µSv, respectively, P = .016). CONCLUSIONS: In the context of the biggest radiation study conducted in patients undergoing transradial catheterization, the instrumented right arm arrangement close to the leg and greater upper leaded shield dimensions were associated with a lower operator radiation exposure. Our findings emphasize the importance of implementing simple preventive measures to mitigate the extra risks of radiation exposure with right radial as compared with femoral access.

Determinants of operator radiation exposure during percutaneous coronary procedures.

BACKGROUND: Radiation exposure is an important issue for interventional cardiologists that is often underevaluated. Our aim was to evaluate determinants of operator radiation exposure during percutaneous coronary procedures. METHODS: The RADIANT (NCT01974453) is a prospective, single-center observational study involving 4 expert operators and 2 fellows performing percutaneous coronary procedures. The operator radiation dose was evaluated using dedicated electronic dosimeters in 2,028 procedures: 1,897 transradial access (TRA; 1,120 right and 777 left TRA) and 131 transfemoral access (TFA). RESULTS: In the whole population, operator radiation dose at the thorax did not differ between TFA (9µSv [interquartile range 5-18µSv]) and TRA (9µSv [4-21µSv]), but after propensity score matching analysis, TFA showed lower dose (9µSv [5-18µSv]) compared with TRA (17µSv [9-28µSv], P<.001). In the whole transradial group, left TRA (5µSv [2-12µSv]) was associated with significant lower operator dose compared with right TRA (13µSv [6-26µSv], P<.001).The use of adjunctive protective pelvic drapes was significantly associated with lower radiation doses compared with procedures performed without drapes (P<.001). Among the operators, an inverse relation between height and dose was observed. Finally, left projections and the use of angiographic systems not dedicated for coronary and high frame rates were all associated with a significant higher operator radiation exposure. CONCLUSIONS: In a high-volume center for transradial procedures, TFA is associated with lower operator radiation dose compared with TRA. The use of adjunctive anti-rx drapes seems a valuable tool to reduce the higher operator radiation exposure associated with TRA.

Radial artery occlusion and hand strength after percutaneous coronary procedures: Results of the HANGAR study.

OBJECTIVES: The aim of this prospective study was to evaluate muscle force of the hand, thumb, and forefinger in patients with prolonged radial occlusion after transradial percutaneous coronary procedures. BACKGROUND: There are no data on hand strength and function in patients with prolonged radial occlusion after percutaneous coronary procedures. METHODS: Elective patients with chronic stable angina undergoing percutaneous coronary procedures were evaluated the day before the procedure for radial artery patency, Allen test, hand grip, and thumb and forefinger pinch tests. The same measures were performed the day after the procedure and at follow-up. At follow-up, patients were divided in two groups according to the radial patency (group 1) or occlusion (group 2). RESULTS: Of the 99 patients included in the study, 90 patients had a patent radial artery (group 1), and nine (9.1%) patients had an occluded artery (group 2). At baseline, there were no significant differences in hand grip test between the two groups (42 ± 11 kg in group 1 and 41 ± 17 kg in group 2, P = 0.74). In both groups, after the procedure, the hand grip test values was significantly reduced compared with baseline values (40 ± 11 kg in group 1, P < 0.0001 and 37 ± 17 kg in group 2, P = 0.007). Finally, at follow-up, in both groups, the hand grip test values returned to baseline values. Thumb and forefinger pinch tests did not show significant differences after the procedure and at follow-up, compared with baseline. CONCLUSIONS: Radial artery occlusion after percutaneous coronary procedures was not associated with a reduction in hand and finger strength.

Transradial approach (left vs right) and procedural times during percutaneous coronary procedures: TALENT study.

BACKGROUND: most of the studies assessing transradial approach for coronary angiography (CA) have been performed through right radial approach (RRA). Our aim was to evaluate the safety and efficacy of left radial approach (LRA) compared with RRA for coronary procedures. METHODS: from January 2009 to December 2009, in 2 hospitals, 1,540 patients were randomized to RRA (770 patients) or LRA (770 patients) for percutaneous coronary procedures. The primary end point was fluoroscopy time for CA and for percutaneous coronary intervention (PCI) evaluated independently. Prespecified subgroup analyses according to patient age and operator experience were planned. RESULTS: in 1,467 patients (732 RRA and 735 LRA), a CA (diagnostic group) was performed, and in 688 (344 each for RRA and LRA), a PCI. In the diagnostic group, LRA was associated with significantly lower fluoroscopy time (149 seconds, interquartile range [IQR] 95-270 seconds) and dose area product fluoroscopy (10.7 Gy cm(2), IQR 6-20.5 Gy cm(2)) compared with the RRA (168 seconds, IQR 110-277 seconds, P = .0025 and 12.1 Gy cm(2), IQR 7-23.8 Gy cm(2), P = .004, respectively). In the PCI group, there were no significant differences in fluoroscopy time (614 seconds, IQR 367-1,087 seconds for LRA and 695 seconds, IQR 415-1,235 seconds, P = .087 for RRA) and dose area product fluoroscopy (53.7 Gy cm(2), IQR 29-101 Gy cm(2) for LRA and 63.1 Gy cm(2), IQR 31-119 Gy cm(2), P = .17 for RRA). According to subgroup analyses, the differences between LRA and RRA were confined to older patients (≥ 70 years old) and to operators in training. CONCLUSIONS: left radial approach for coronary diagnostic procedures is associated with lower fluoroscopy time and radiation dose adsorbed by patients compared with the RRA, particularly in older patients and for operators in training.

Extended Protective Shield Under Table to Reduce Operator Radiation Dose in Percutaneous Coronary Procedures.

BACKGROUND: Different tools and devices are effective to reduce operator radiation exposure at thorax level during percutaneous coronary procedures, but the operator radiation dose received at pelvic region still remains high. Our aim was to evaluate the efficacy of under-the-table adjunctive shields to reduce operator radiation exposure during percutaneous coronary procedures Methods and Results: The EXTRA-RAD study (Extended Protective Shield Under Table to Reduce Operator Radiation Dose in Percutaneous Coronary Procedures) is a prospective, single-center, randomized study. Patients who underwent transradial coronary procedures were randomized into 2 groups: group 1 (standard arrangement) and group 2 (adjunctive anti-rx shield under the angiographic table). In group 2, a further randomization was performed to compare 2 different under-the-table shields (a small curtain and a drape). A total of 205 procedures (122 diagnostic coronary angiographies and 83 percutaneous coronary interventions) performed in 157 patients by 4 different operators were included without significant differences in clinical and procedural characteristics between groups. The use of adjunctive shields was associated with lower radiation dose compared with no shield at pelvic region (42 µSv [14-98] in group 1, 13 µSv [5-27] in group 2; P<0.0001) and also at thorax level (4 µSv [1-13] in group 1, 2 µSv [1-4] in group 2; P=0.001). The reduction in dose was observed in all the operators. No significant differences were observed in pelvic dose using the 2 different shields ( P=0.183). CONCLUSIONS: The use of adjunctive anti-rx shields under the angiographic table during transradial coronary procedures is associated with a significant lower radiation dose to operators at pelvic and thorax level. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03259126.

[SICI-GISE Position paper: Enhancing radiation safety in the catheterization laboratory]. / Position paper SICI-GISE: Miglioramento della radioprotezione nel laboratorio di Emodinamica.

The radiation dose received by interventional cardiologists during their activity in the catheterization laboratory is a matter of concern in terms of possible deterministic and stochastic risk. At the same time, very often, the knowledge of the effect and consequences of radiation exposure in the interventional cardiology community is limited. This document endorsed by the Italian Society of Interventional Cardiology (SICI-GISE) provides recommendations for cardiologists' radiation protection. Radiation safety considerations dedicated to women and other staff personnel working in the catheterization laboratory are also discussed.

Operator Pelvic Radiation Exposure During Percutaneous Coronary Procedures.

OBJECTIVES: To evaluate operator pelvic radiation exposure during percutaneous coronary procedures. BACKGROUND: During percutaneous coronary procedures, the operator's pelvic region is close to the x-ray source and is probably exposed to more radiation than the operator's thorax. However, no data are available on the pelvic radiation exposure of interventional cardiologists. METHODS: The RADIANT study (NCT01974453) is a prospective, single-center, observational study evaluating operator radiation exposure during percutaneous coronary procedures using electronic dosimeters placed at thorax level. In the last period of the study enrollment, a single operator was also equipped with an adjunctive electronic dedicated dosimeter to evaluate pelvic radiation exposure. RESULTS: From a total of 2028 procedures included in the RADIANT study, operator pelvic doses were available for 138 procedures (68 right radial, 55 left radial, and 15 transfemoral). Median fluoroscopy time was 226 sec (interquartile range [IQR], 117-407 sec) and the dose-area product (DAP) was 15.3 Gy•cm² (IQR, 9.3-27.8 Gy•cm²). Radiation dose at pelvic region was significantly higher (40.1 µSv; IQR, 22.7-76.3 µSv) compared to thorax dose (5.6 µSv; IQR, 1.5-12 µSv; P<.001) even after normalization by DAP (2.98 µSv/Gy•cm² [IQR, 1.6-4.6 µSv/Gy•cm²] at pelvic vs 0.33 µSv/Gy•cm² [IQR, 0.11-0.81 µSv/Gy•cm²] at thorax level; P<.001). No significant differences were observed comparing pelvic dose in right radial (42 µSv), left radial (39 µSv), or femoral access (40 µSv; P=.43). CONCLUSIONS: Operator radiation exposure to the pelvic region during percutaneous coronary procedures is significantly higher compared to thorax radiation dose independently of the vascular access site employed.

Staff radiation dose during percutaneous coronary procedures: Role of adjunctive protective drapes.

BACKGROUND: The use of adjunctive protective drapes placed on the patient protects the operating physician from scatter radiation during percutaneous coronary procedures (PCP). No data are available on the effect of these drapes for staff members' radio-protection. PURPOSE: To evaluate staff radiation exposure during PCP and the effect of adjunctive protective drapes on dose reduction. METHODS: The RADIANT study (NCT01974453) is a prospective, observational study evaluating operator radiation exposure during PCP using electronic dosimeter. In a sub-group of procedures all the staff members (II operator, nurse circulator and technologist) were also equipped with a dedicated electronic dosimeter. RESULTS: From a total of 2028 procedures included in the RADIANT study, staff members' doses were available for 122 procedures (67 coronarography and 55 percutaneous coronary interventions). Median fluoroscopy time was 306 s (Interquartile range 155-526 s) and the dose area product (DAP) was 18.0 Gy*cm2 (10-35.5 Gy*cm2). The radiation exposure was highest for the operating physician (6.7 µSv) and progressively lower for the nurse circulator (1.8 µSv), the II operator (1 µSv) and the technologist (0.7 µSv, p < 0.001). Protective pelvic drapes were used in 43 procedures and associated with a lower radiation exposure for all staff members (14 µSv vs 2.2 µSv for operating physician, p < 0.001, 1.7 µSv vs 0.49 µSv for II operator, p < 0.001, 2.16 µSv vs 0.93 µSv for nurse circulator, p = 0.02 and 0.85 µSv vs 0.39 µSv for technologist, p = 0.01). CONCLUSIONS: The use of adjunctive protective drapes is effective in reducing radiation protection for all staff members during PCP.

Radiation dose absorbed by operators during transradial percutaneous coronary procedures comparing different protective drapes: the RADIATION study.

AIMS: The aim of this study was to compare different radiation protection drapes in terms of radiation dose absorbed by operators during right or left transradial procedures. METHODS AND RESULTS: Patients who underwent transradial coronary procedures were randomised initially into four groups: Group 1 (no drapes), Group 2 (drape on patient's arm), Group 3 (pelvic drape), Group 4 (combined arm and pelvic drapes). Subsequently, each group was further randomised to right or left radial access. The primary endpoint was the operator radiation dose at the thorax. A total of 452 procedures were included. The use of drapes was associated with a lower radiation dose compared to no drapes (8.6 µSv [4.1-17.9] Group 1, 5.8 µSv [3.4-13] Group 2, 3.6 µSv [2.1-6.9] Group 3, 3.7 µSv [1.9-10.3] Group 4, p<0.001). Among radiation protection drapes groups the radiation dose was significantly lower in Groups 3 and 4 compared to Group 2 (p<0.008). Compared to Group 1, the dose in Group 2 was significantly lower only in right radial procedures (p<0.008) whereas in Groups 3 and 4 the dose was significantly lower in both radial accesses (p<0.008). CONCLUSIONS: The use of radiation protection drapes during transradial coronary procedures is associated with a significantly lower radiation dose to operators, with the pelvic drape more effective than the use of a single arm drape.

Radiation dose among different cardiac and vascular invasive procedures: The RODEO study.

BACKGROUND: Interventional radiology and cardiology procedures contribute significantly to the collective dose of radiation exposure from medical interventions. Recent and dedicated studies comparing directly these procedures in term of patient radiation exposure are lacking. Our aim was to compare radiation exposure among different interventional procedures performed under fluoroscopic guidance. METHODS: The RODEO study (NCT: 02972736) is an international observational retrospective multicenter study enrolling all patients undergoing diagnostic or interventional procedures performed by different interventional operators (i.e. radiologists, interventional cardiologists or electrophysiologists) in 6 centers, without exclusion criteria. The primary end-point of the study was the comparison of dose area product (DAP) among interventional cardiology, electrophysiology or interventional radiology procedures. RESULTS: A total of 17,711 procedures were included in the study: 13,522 interventional cardiology, 2352 electrophysiology and 1864 interventional radiology procedures. The highest DAP values were observed for interventional radiology procedures (74Gy∗cm2 [Interquartile range 27-178Gy∗cm2]), followed by interventional cardiology (40Gy∗cm2 [22-78Gy∗cm2]) and electrophysiology procedures (13Gy∗cm2 [4-44Gy∗cm2], p<0.0001). In term of specific procedures, the highest DAP values were observed in structural or valvular cardiac procedures (134Gy∗cm2 [51-260Gy∗cm2]) whereas the lowest DAP values in pacemaker insertion (11Gy∗cm2 [4-28Gy∗cm2]). CONCLUSION: In this large multicenter study, the highest radiation exposure was observed in procedures performed by interventional radiologists. However, among specific procedures, structural or valvular cardiac procedures were associated with the highest radiation exposure.

Radiation Exposure and Vascular Access in Acute Coronary Syndromes: The RAD-Matrix Trial.

BACKGROUND: It remains unclear whether radial access increases the risk of operator or patient radiation exposure compared to transfemoral access when performed by expert operators. OBJECTIVES: This study sought to determine whether radial access increases radiation exposure. METHODS: A total of 8,404 patients, with or without ST-segment elevation acute coronary syndrome, were randomly assigned to radial or femoral access for coronary angiography and percutaneous intervention, and collected fluoroscopy time and dose-area product (DAP). RAD-MATRIX is a radiation sub-study of the MATRIX (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX) trial. We anticipated that 13 or more operators, each wearing a thorax (primary endpoint), wrist, and head (secondary endpoints) lithium fluoride thermoluminescent dosimeter, and randomizing at least 13 patients per access site, were needed to establish noninferiority of radial versus femoral access. RESULTS: Among 18 operators, performing 777 procedures in 767 patients, the noninferiority primary endpoint was not achieved (p value for noninferiority = 0.843). Operator equivalent dose at the thorax (77 µSv) was significantly higher with radial than femoral access (41 µSv; p = 0.02). After normalization of operator radiation dose by fluoroscopy time or DAP, the difference remained significant. Radiation dose at wrist or head did not differ between radial and femoral access. Thorax operator dose did not differ for right radial (84 µSv) compared to left radial access (52 µSv; p = 0.15). In the overall MATRIX population, fluoroscopy time and DAP were higher with radial compared to femoral access: 10 min versus 9 min (p < 0.0001) and 65 Gy·cm2 versus 59 Gy·cm2 (p = 0.0001), respectively. CONCLUSIONS: Compared to femoral access, radial access is associated with greater operator and patient radiation exposure when performed by expert operators in current practice. Radial operators and institutions should be sensitized towards radiation risks and adopt adjunctive radioprotective measures. (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX; NCT101433627).

Operator radiation exposure during right or left transradial coronary angiography: A phantom study.

BACKGROUND: Previous studies showed a possible lower radiation dose absorbed by operators comparing LRA and RRA for percutaneous coronary procedures. The reasons of this lower radiation dose are not well known. The aim of this study was to evaluate the radiation dose absorbed by operators comparing left with right radial access (LRA and RRA respectively) during a simulated diagnostic coronary angiography using a phantom. METHODS: A coronary angiography examination was simulated on a phantom by 5 operators using eight projections with 5 seconds fluoroscopy each. Each operator was equipped with 4 electronic dosimeters placed at thorax, at left wrist, at left head and at hip level. Radiation doses were expressed in picosievert and normalized by dose area product. RESULTS: LRA compared to RRA was associated with a significant lower operator dose at wrist (36pSv/cGYcm(2) [IQR 18-59pSv/cGYcm(2)] and 48pSv/cGYcm(2) [IQR 22-148pSv/cGYcm(2)] respectively, p=0.01) and thorax (3pSv/cGYcm(2) [IQR 2-5pSv/cGYcm(2)] and 10pSv/cGYcm(2) [6-23pSv/cGYcm(2)] respectively, p<0.001) but with a significant higher radiation dose at hip level (102pSv/cGYcm(2) [IQR 44-199pSv/cGYcm(2)] and 67pSv/cGYcm(2) [IQR 39-132pSv/cGYcm(2)] respectively, p=0.02). Conversely the radiation dose at left side of the head did not show significant differences between the two approaches. CONCLUSIONS: In this phantom study simulating a diagnostic coronarography the use of LRA compared to RRA was associated with a significant lower radiation dose at wrist and thorax but with an increased dose at hip level. SUMMARY: To evaluate the radiation dose absorbed by operators comparing left with right radial access (LRA and RRA respectively) we simulated a diagnostic coronary angiography using a dedicated phantom. Operators were equipped with dedicated electronic dosimeters at wrist, hip, head and thorax level. LRA compared to RRA was associated with a significant lower operator dose at wrist and thorax but with a significant higher radiation dose at hip level whereas the radiation dose at left side of the head did not show significant differences between the two approaches.

Randomized comparison of operator radiation exposure comparing transradial and transfemoral approach for percutaneous coronary procedures: rationale and design of the minimizing adverse haemorrhagic events by TRansradial access site and systemic implementation of angioX - RAdiation Dose study (RAD-MATRIX).

BACKGROUND: Radiation absorbed by interventional cardiologists is a frequently under-evaluated important issue. Aim is to compare radiation dose absorbed by interventional cardiologists during percutaneous coronary procedures for acute coronary syndromes comparing transradial and transfemoral access. METHODS: The randomized multicentre MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) trial has been designed to compare the clinical outcome of patients with acute coronary syndromes treated invasively according to the access site (transfemoral vs. transradial) and to the anticoagulant therapy (bivalirudin vs. heparin). Selected experienced interventional cardiologists involved in this study have been equipped with dedicated thermoluminescent dosimeters to evaluate the radiation dose absorbed during transfemoral or right transradial or left transradial access. For each access we evaluate the radiation dose absorbed at wrist, at thorax and at eye level. Consequently the operator is equipped with three sets (transfemoral, right transradial or left transradial access) of three different dosimeters (wrist, thorax and eye dosimeter). Primary end-point of the study is the procedural radiation dose absorbed by operators at thorax. An important secondary end-point is the procedural radiation dose absorbed by operators comparing the right or left radial approach. Patient randomization is performed according to the MATRIX protocol for the femoral or radial approach. A further randomization for the radial approach is performed to compare right and left transradial access. CONCLUSIONS: The RAD-MATRIX study will probably consent to clarify the radiation issue for interventional cardiologist comparing transradial and transfemoral access in the setting of acute coronary syndromes.

Operator radiation exposure during percutaneous coronary procedures through the left or right radial approach: the TALENT dosimetric substudy.

BACKGROUND: Transradial percutaneous coronary procedures may be effectively performed through the right radial approach (RRA) or the left radial approach (LRA), but data on radiation dose absorbed by operators comparing the two approaches are lacking. The aim of the present study was to evaluate radiation dose absorbed by operators during coronary procedures through the RRA and LRA. METHODS AND RESULTS: Three operators were equipped with 5 different dosimeters (left wrist, shoulder, thorax outside the lead apron, thorax under the lead apron, and thyroid) during RRA or LRA for coronary procedures. Each month, the dosimeters were analyzed to determine the radiation dose absorbed. From February to December 2009, 390 patients were randomly assigned to the RRA (185 patients; age, 66±11 years) or the LRA (185 patients; age, 66±11 years). There were no significant differences in fluoroscopy time (for RRA, 369 seconds; interquartile range, 134 to 857 seconds; for LRA, 362 seconds; interquartile range, 142 to 885 seconds; P=0.58) between the 2 groups. There were no significant differences in monthly radiation dose at the thorax (0.85±0.46 mSv for RRA and 1.12±0.78 mSv for LRA, P=0.33), at the thyroid (0.36±0.2 mSv for RRA and 0.34±0.3 mSv for LRA, P=0.87), and at the shoulder (0.73±0.44 mSv for RRA and 0.94±0.42 mSv for LRA, P=0.27). The dose at the wrist was significantly higher for the RRA (2.44±1.12 mSv) compared with the LRA (1±0.8 mSv, P=0.002). In both radial approaches, the thoracic radiation dose under the lead apron was undetectable. CONCLUSIONS: Compared with RRA, LRA for coronary procedures is associated with similar radiation dose for operators at the body, shoulder, or thyroid level, with a possible significant advantage at the wrist. The cumulative radiation dose for both approaches is well under to the annual dose-equivalent limit. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00282646.