Mr U, a 29-year-old teacher, was referred to Dr N, a consultant cardiologist, with a history of several episodes of dizziness, perspiration and palpitations. A 24-hour ECG had shown episodes of tachycardia and bradycardia, and second-degree Mobitz type II heart block was demonstrated when symptomatic.
Dr N recommended a procedure to insert a permanent pacemaker, to which Mr U consented. The procedure was straightforward, with the post-procedure chest x-ray and pacemaker check both recorded as satisfactory. Mr U was discharged home.
Six weeks later, a routine pacemaker check demonstrated a high threshold in the ventricular lead (which could signify potential pacemaker failure), despite satisfactory positions on the chest x-ray. Dr N prescribed a short course of steroids.
The following month, Mr U was admitted to hospital with left-sided chest pain and episodes of tachycardia and bradycardia. Dr N undertook an exploration of the pacemaker system and replaced the ventricular lead. Dr N reviewed the post-intervention chest x-ray and felt it was satisfactory; the patient was discharged.
Mr U was readmitted by ambulance late that evening: a pacemaker check demonstrated that the ventricular lead did not capture the ventricle.
The following day Dr N re-sited the ventricular lead and re-advanced the atrial lead. Again, the post-procedure chest x-ray and pacemaker check were felt by Dr N to be satisfactory. Mr U was kept under observation for two days and advised to keep his arms still. Dr N’s notes stated that he suspected Twiddler’s Syndrome, which occurs when a patient manipulates the pacemaker’s pulse generator and dislodges the leads from their intended location.
A week later, another pacemaker check demonstrated a failure of the pacemaker and the ventricular lead. Mr U, unhappy with his care so far, asked to see a second cardiologist.
He was referred to Dr B, who undertook a revision of the pacemaker. She found the suture sleeves to be loose and that both leads were mobile. Following the procedure, a pacemaker check and chest x-ray were both satisfactory and Mr U was discharged home. He had no further problems with his pacemaker following Dr B’s intervention.
Mr U made a clinical negligence claim against Dr N, alleging that, in the second and third procedures, he had failed to secure the leads to prevent them from moving, and that he had failed to check appropriate lead positioning during and after the procedures.
Expert opinion
Medical Protection sought expert opinion from a consultant cardiologist. The expert was critical of several aspects of the care provided by Dr N.
First, the expert cited that the post-procedure chest x-rays from the second and third procedures showed unsatisfactory lead positions, which would have made lead dislodgement likely. Also, she could find no evidence of Twiddler’s Syndrome on any chest x-ray.
The expert also noted that, in the fourth procedure, Dr B could not find evidence of lead sutures, suggesting that the leads were not secured adequately.
Based on the expert opinion, the case was deemed indefensible and was settled for a moderate sum.
Learning points
- It is important to take extra care suturing the leads during a revision procedure, especially if there has already been an episode of lead migration.
- Twiddler’s Syndrome is a well-known but infrequent cause of pacemaker malfunction. A chest x-ray would usually show the two leads migrated to the same degree and rotation of the pulse generator, so making the diagnosis.