Monday, February 21, 2011

Electrophysiologists' New Annuity: Percutaneous Aortic Valve Replacements

From Circulation:
One third of patients undergoing a CoreValve transcatheter aortic valve implantation procedure require a permanent pacemaker (PPM) within 30 days. Periprocedural atrioventricular block, balloon predilatation, use of the larger CoreValve prosthesis, increased interventricular septum diameter and prolonged QRS duration were associated with the need for PPM.
With the compact AV node immediately adjacent to the non-coronary cusp of the aortic valve, it's remarkable AV block is not more frequent.

From the discussion section of the paper came these recommendations regarding the monitoring requirements after transcatheter aortic valve implantation (TAVI):
Recommendations based on our findings would suggest that patients who do not develop a broad QRS complex postprocedure can be safely discharged, from the electrophysiological viewpoint, without need for prolonged monitoring, especially if there has been no disturbance of conduction during implantation and the smaller 26-mm valve has been used. However, patients who develop bundle-branch block should probably be monitored for a minimum of 5 days (emphasis mine) for the development of higher-grade AV block.
Interestingly, the conclusions of the same article recommend that 7 days of monitoring may be more appropriate:
The increased rates of PPM implantation in patients with postprocedural bundle-branch block and overall median time to implantation of 4 days (interquartile, range 2 to 7 days) in those who required pacing lead us to recommend that these patients be observed for higher-grade conduction disturbances for up to a week postprocedurally, with greatest care taken in those with periprocedural AV block, those receiving the larger 29-mm device, and patients with greater IVSd."
Even with a week's monitoring, pacemakers were seen even later in a small group of patients (from the Results section of the paper):
Eighty-one of 243 patients (33.3%) underwent PPM implantation within 30 days. Nine patients received their implants on the same day as the index procedure. A further 7 patients (2.9%) underwent PPM implantation during longer-term follow-up at 31, 42, 42, 53, 132, 152, and 187 days.

Khawaja MZ, Rajani R, Cook A, et al. "Permanent Pacemaker Insertion After CoreValve Transcatheter Aortic Valve Implantation: Incidence and Contributing Factors (the UK CoreValve Collaborative)" Circulation 2011 DOI: 10.1161/CIRCULATIONAHA.109.927152

1 comment:

Anonymous said...

Isn't the Core valve still in clinical trials? Unless you are at an implanting site you won't be seeing an annuity soon.

If Obamacare is not repealed, one wonders if TAVI will be covered for the elderly with co-morbidities.