Asymptomatic perioperative arrhythmias can lead to sudden cardiac death after surgery: Researchers

Vascular surgery may be accompanied by cardiovascular complications, like ventricular tachyarrhythmia (VT). Though, these arrhythmias initially might be asymptomatic, they can lead to increased risk for late sudden cardiac death after surgery. Researchers from the Netherlands believe that cardiac high-risk patients with new-onset perioperative VT might benefit from preemptive cardioverter defibrillator (ICD) implantation in addition to optimal focused medical therapy. At the 64th Vascular Annual Meeting® presented by the Society for Vascular Surgery® details of their new study were revealed.

According to Tamara Winkel, MD, research fellow from the vascular surgery department of the Erasmus Medical Center in Rotterdam, data from 483 vascular surgery patients without a history of cardiac arrhythmias were reviewed. Preoperative cardiac risk factors, left ventricular function, medical therapy, and perioperative ischemia were noted.

"Our objective was to identify perioperative new-onset VT's using a continuous electro-cardiography (ECG) device for 72 hours since new-onset perioperative arrhythmias are often short-lived and asymptomatic, making detection difficult and causing the true incidence to be understated. The ECG monitoring period was started one day prior to surgery and continued up to two days afterwards," said Dr. Winkel. "New-onset perioperative VT, defined as sustained VT, was detected in 33 (7%) patients" said Dr. Winkel. "Patients with perioperative VT had a significantly reduced left ventricular function, and were undertreated with statins."

Dr. Winkel added that VT patients had an increased incidence of myocardial ischemia (30 %) compared to patients without VT (18 %). During a median follow-up of two years, cardiac death occurred in 56 patients, 48 of which were classified as sudden death. Of all patients with perioperative VT, seven (21%) died due to sudden cardiac death within three years of vascular surgery. "By extending the ECG monitoring period with an implantable monitoring device, like Reveal XT®, we could capture more episodes of new-onset VT, presenting outside the 72 hour ECG window, which in turn could enhance detection of those at highest risk of sudden death. This last statement is based on the preliminary results from an ongoing study involving 28 patients using the Reveal XT® device and the fact that a large portion of the patients suffering from sudden cardiac death was asymptomatic on 72 hours ECG recording."

The use of a preemptive ICD may avoid sudden death. "After adjusting for risk factors, new-onset perioperative VT was associated with sudden cardiac death," said Dr. Winkel. "Longer continuous implanted cardiac monitors could detect these perioperative episodes of arrhythmia which in turn could have important therapeutic and prognostic consequences. In theory preemptive ICD implantation would benefit high-risk surgery patients and it is now important that more research be done in the future to support that."