Co-STAR Hints That Colchicine May Curb Rhythm Disturbances After TAVI

 A small, single-center study named Co-STAR suggests that short-term colchicine use during TAVI (transcatheter aortic valve implantation) for severe aortic stenosis may reduce the risk of new-onset atrial fibrillation (AF) and the need for a new permanent pacemaker.

Researchers reported at TCT 2024 that colchicine may also reduce the risk of leaflet thickening in patients who underwent 4D-cardiac computed tomography angiography at 30 days. However, the trial was stopped early after five strokes occurred among the colchicine-treated group, while none occurred in the placebo group. Despite this, investigators believe the strokes may not be linked to the medication.

The lead investigator noted a higher prevalence of prior stroke in the colchicine group, which may explain the stroke events. He also referenced that colchicine trials for coronary artery disease have not shown safety issues, suggesting this finding might be coincidental.

In a larger, separate study called CLEAR SYNERGY, also presented at TCT, colchicine did not significantly reduce major adverse cardiovascular events in patients post-PCI after acute myocardial infarction.

Inflammation, a known factor in cardiac arrhythmias, inspired this trial. The study aimed to explore whether colchicine could mitigate rhythm disturbances following TAVI by targeting inflammation in the "landing zone" of the valve implantation.

The study enrolled 60 patients on a colchicine regimen of 1 mg before the procedure, followed by 0.5 mg for 12 days, with another 60 patients receiving a placebo. All participants, averaging 80 years old, were monitored for new-onset AF or conduction issues requiring a new pacemaker.

The primary endpoint of AF or pacemaker implantation at 30 days occurred in 10% of colchicine-treated patients compared to 25% in the placebo group. Colchicine-treated patients showed a 27.1% incidence of reduced leaflet thickening compared to 54.2% in the placebo group, with no difference in antithrombotic therapy.

While the results are promising, further research with a larger study population is necessary.