radiation

Had my pacemaker/defibrillator replaced a week ago. Doc had trouble threading leads into heart. I was under these cameras, which I believe are the same for heart cath, for 4.5 hours. Can this much radiation all at once be dangerous? I have been nauseated and dragging since procedure.

[ed34]

The dye would be virtually out of your body within a couple of days and it's normal to feel a bit tired for about a week after the procedure. I would give it a few more days and if things don't improve, notify your cardiologist. Has your medication been changed at all?

[kenkeith]

From what I have read exposure greater than an hour can be harmful.  Excluding DNA the harm is usually seen on the skin of the chest.  

The absorbed dose rate in the skin from the direct beam of a fluoroscopic x-ray system is typically between 0.02 Gy/min and 0.05 Gy/min (2 to 5 rad/min), but may be higher, depending on the mode in which the equipment is operated and the size of the patient.

Even typical dose rates can result in skin injury after less than one hour of fluoroscopy.
Physicians should know that radiation-induced injuries from fluoroscopy are not immediately apparent. Other than the mildest symptoms, such as transient erythema, the effects of the radiation may not appear until weeks following the exposure. Physicians performing these procedures may not be in direct contact with the patients following the procedure and may not observe the symptoms when they occur. Missing the milder symptoms in some patients can lead to surprise at the magnitude of the absorbed doses delivered to the skin of other patients when more serious symptoms appear. For this reason, we recommend that information be recorded in the patient's record which permits estimation of the absorbed dose to the skin. Patients should also be advised to report signs and/or symptoms of radiation induced injury to their attending physician.

You should follow up with your doctor....4 hours is long time!

[ed34]

You don't mention any skin burns, just nausea. My last procedure was just over 4 hours, and it is not uncommon for blockage removals to take several hours.

[kenkeith]

It depends on what equipment is utilized. Conclusion Electroanatomic navigation systems such as NavX can be used for cardiac imaging during single-lead atrioventricular pacemaker implantation as a reliable and safe alternative to fluoroscopy.
Mayo Clinic does the procedure in 2 to 3 hours.

>>"Aims Fluoroscopy is the standard and almost unique tool used for cardiac imaging during permanent pacemaker implantation, and its use implies exposure of patients and operators to radiation. The usefulness for this purpose of electroanatomic systems not based on fluoroscopy is unknown. Our aim was to study the feasibility of implanting single-lead VDD pacemakers without the use of fluoroscopy.  Methods and results EnSite NavXw, a catheter navigation tool based on the creation of a voltage gradient
across the thorax of the patient, was used as an exclusive imaging tool during the implantation of single-lead atrioventricular (VDD) permanent pacemakers in 15 consecutive patients with atrioventricular block and normal sinus node function. A retrospective series of 15 consecutive patients in whom VDD pacemakers were implanted under fluoroscopic guidance was used as a control group. The pacemaker
could be implanted in all patients. Time spent to obtain the right ventricle anatomy was 10.1+ 5.4 min and time to place the lead in an adequate position was 10.1+7.8 min. Total implant time was 59.3+15.6 min (51.5+12.3 min in the control group; P ¼ 0.14). In one patient, a short pulse of radioscopy was needed for a correct catheterization of the subclavian vein. No complications were observed during the procedure. One lead dislodgement that required re-operation was detected 24 h after implantation. At 3 months follow-up, all pacemakers were functioning properly, with adequate
pacing and sensing thresholds".