Evaluation of a suspended radiation protection system to reduce operator exposure in cardiology interventional procedures.

OBJECTIVES: To investigate a novel suspended radiation shield (ZG), in reducing operator radiation exposure during cardiology interventions. BACKGROUND: Radiation exposure to the operator remains an occupational health hazard in the cardiac catheterization laboratory. METHODS: An anthropomorphic mannequin simulating an operator was placed near a phantom, simulating a patient. To measure the operator dose reduction, thermoluminescent detectors (TLDs) were inserted into the head and into the eye bulbs of the mannequin, while electronic dosimeters were positioned on the temple and at the level of the thyroid. Measurements were performed without and with the ZG system in place. Physician exposure was subsequently prospectively measured on the torso, on the left eye and on upper arm using the same electronic dosimeters, during clinical procedures (coronary angiography (CA) and percutaneous coronary intervention (PCI)). The physicians dose reduction was assessed by comparing operator dose when using traditional radioprotection garments (Phase 0) versus using the ZG system (Phase 1). RESULTS: Dose reductions as measured on the mannequin ranged from 66% to the head, to 100% to the torso. No dose was detected at the level of the torso and thyroid with ZG. When comparing CA and PCI procedures between Phase 0 and Phase 1, a significant difference (p < 0.001) was found for the left eye and the left wrist. Dose reduction as measured during clinical procedures for left eye/upper arm were on average 78.9%/95.6% for CA and 83.0%/93.0% for PCI, respectively (p < 0.001 for both). CONCLUSIONS: The ZG systems has a great potential to significantly reduce operator dose through the creation of a nearly zero-radiation work environment.

Patient exposure data and operator dose in coronary interventional procedures: Impact of body-mass index and procedure complexity.

PURPOSE: The aim of this study was to assess patient exposure data and operator dose in coronary interventional procedures, when considering patient body-mass index and procedure complexity. METHODS: Total air kerma area product (PKA), Air-Kerma (AK), Fluoroscopy time (FT), operator dose and patient body-mass index (BMI) from 97 patients' procedures (62 coronary angiography (CA) and 35 Percutaneous Coronary Intervention (PCI) were collected for one year. For PCI procedures, also the complexity index-CI was collected. Continuous variables for each of the 2 groups procedures (CA and PCI) were compared as medians with interquartile range and using Mann-Whitney U test. Multiple group data were compared using Kruskal-Wallis test (significance: p < 0.05). RESULTS: Median PKA was 63 and 125 Gy cm2 for CA and PCI respectively (p < 0.001); FT was 3 and 14 min, respectively (p < 0.001). PKA and FT significantly increased (p < 0.05) with BMI class for CA procedures. PKA and FT also increased in function of CI class for PCI, thought significantly only for FT (p < 0.001), possibly because of the low number of PCI procedures included; cine mode contributed most to PKA. Significant dose variability was observed among cardiologists for CA procedures (p < 0.001). CONCLUSIONS: Dose references levels for PKA and FT in interventional cardiology should be defined - on a sufficient number of procedures- in function of CI and BMI classes. These could provide an additional tool for refining a facility's quality assurance and optimization processes. Dose variability associated with cardiologists underlines the importance of continuous training.

In-hospital complications of percutaneous intraaortic balloon counterpulsation.

Complications related to intraaortic balloon counterpulsation pumping (IABP) remain a problem despite the development of small caliber balloon catheter shafts and introducer sheaths. The authors report their experience in counterpulsation-related complications of 201 consecutive patients who underwent 212 percutaneous counterpulsation balloon insertions from June 1989 to June 1996 by use of balloons with 8-9.5 French shafts. Of these, 82% were men and 36 (18%) were women, with a mean age of 61 +/-12 years. Indications for counterpulsation were acute myocardial infarction (AMI) (67%), severe left ventricular failure without AMI (20%), dilated cardiomyopathy (4%), unstable angina (3%), high-risk supported percutaneous coronary angioplasty (2%), and others (4%). IABP was instituted at the bedside in the intensive care unit in 82 patients (39%) and in the catheterization laboratory in 130 (61%). Median duration of counterpulsation was 48 hours (range 30 minutes to 25 days) with successful weaning from counterpulsation in 70% (148 of 212) of procedures. Overall in-hospital mortality rate was 45% (90 of 201). The overall complication rate was 22/212 (10.4%). Major complications were present in 10/212 procedures (4.7%): 6 patients with limb ischemia (1 death directly attributed to this complication, 1 with associated septicemia and limb amputation, 3 requiring surgical thromboembolectomy, and 1 with persistent limb ischemia treated medically until his death caused by intractable left ventricular failure), 2 with important bleeding (1 fatal despite vascular surgical repair and 1 requiring blood transfusion) and 2 with balloon rupture requiring vascular surgery. Minor complications were present in 12 procedures (5.7%), 6 with limb ischemia, 3 with local bleeding, and 3 with catheter dysfunction. All of these resolved after balloon removal and required no further intervention. When limb ischemia did develop it occurred after a median delay of 24 hours following balloon insertion (range 2 to 98 hours). The only predictor of limb ischemia among baseline clinical and procedure-related variables was an age greater than 60 years. Compared with previous recent studies, the rate of complications observed in this study performed with small balloon catheters was acceptably low. Limb ischemia was the most frequent complication, often occurred early, and required further intervention in half the cases.