Permanent pacemaker implantation late after TAVI uncommon

Reuters Health - 26/08/2021 - The need for a permanent pacemaker (PPM) late after transcatheter aortic-valve implantation (TAVI) is uncommon and often not caused by the TAVI procedure itself, according to retrospective data from Switzerland.

In a paper in Heart Rhythm, the study team notes that, despite advances in TAVI procedure and valve design, impairment of atrioventricular (AV) conduction may occur late after TAVI and progress to complete AV block.

"The management of these patients remains clinically challenging. PPM implantation is indicated in patients with advanced AV conduction impairment or in those deemed at high risk," they point out.

Yet, data are lacking regarding the long-term incidence, indications and risk factors or PPM implantation in patients discharged after TAVI without a PPM.

To investigate, Dr. Laurent Roten and colleagues with Bern University Hospital identified 1,059 patients discharged after TAVI without PPM.

Sixty-two of them (5.9%) underwent PPM implantation at a median of 305 days after discharge for TAVI, corresponding to an incidence rate of 21 per 1,000 person-years.

This rate is similar to a recent Finnish study, where 6.2% of patients received a PPM 30 days to five years after TAVI, the study team says.

More than 40% of PPM implantations late after TAVI occurred within six months after TAVI with decreasing incidence thereafter.

In their cohort, clinical symptoms leading to PPM implantation were present in more than half of patients (54.8%) with syncope the most common one (31%).

"The presence of new left bundle branch block (LBBB) after TAVI was among the strongest independent predictors of PPM implantation late after TAVI due to AV conduction impairment, in addition to the presence of first degree AV block," the researchers report.

However, they say, it's also noteworthy that nearly half of the patients with PPM implantation late after TAVI had no bundle branch block after TAVI, "suggesting that the indication for PPM implantation was not directly related to the TAVI procedure," the study team says.

"Moreover, a quarter of PPMs were implanted due to sick-sinus syndrome or other procedures during follow-up, like valve-in-valve procedures and for cardiac resynchronization therapy (CRT) / implantable cardioverter-defibrillator (ICD) indications. These additional PPM implantations were most probably not directly associated with the initial TAVI procedures," they point out.

The researchers caution that this was a retrospective, single-center study and larger studies are needed to confirm the findings.

Commenting on this research in an editorial, Dr. Yousif Ahmad of Yale School of Medicine, in New Haven, Connecticut, and Dr. Raj Makkar of Smidt Heart Institute, in Los Angeles, say it's "crucial to understand the clinical outcomes both when pacemakers are implanted and when they are deferred."

The researchers should be "applauded for generating new data in the field of conduction disease after TAVI" in a relatively large cohort.

The editorial writers say it's important to note that the study was retrospective, non-randomized and had a relatively prolonged duration; "meaning the results are necessarily affected by changes in TAVI technology, implant techniques and patient characteristics."

"The TAVI procedure is now at a stage of maturity that it is unlikely that there will be future large, epochal changes in either technology or technique that will provide very substantial advances in clinical outcomes. Instead, the focus must now be on marginal gains from smaller refinements," Dr. Ahmad and Dr. Makkar say.

"In the contemporary era of TAVI being offered to low-risk patients, and with increasing expectation of next-day discharge, it is imperative that we concurrently focus both on reducing the incidence of post-TAVI conduction disturbances and on identifying which patients truly require permanent pacemakers," they add.

The study had no funding. Dr. Roten has received speaker honoraria from device makers.

SOURCE: https://bit.ly/3DqYA9V and https://bit.ly/3gw4axU Heart Rhythm, online August 15, 2021.

By Reuters Staff



Posted on 26 August 20212 September 2021