乌鸦传媒

FT. LAUDERDALE -- Clinicians can be "aggressive" when deciding whether to replace a left ventricular assist device (LVAD) because the reoperation poses low risk, a small study showed.

Of the 45 patients who underwent a first device exchange, only one patient had an early death, John M. Stulak, MD, of the University of Michigan Medical Center in Ann Arbor, Mich., and colleagues found.

Eight patients had multiple device exchanges, and out of the 57 total reoperations only two patients had early deaths, Stulak reported here at the Society of Thoracic Surgeons meeting.

Due to extended transplant wait times, patients are being supported for longer periods with LVADs. In addition, LVADs have been approved for destination therapy, which has increased the number of implant patients as well as the duration the device will stay implanted.

"While effective, this comes with increased potential need for device exchange when complications arise," Stulak said.

He noted the sparse data specifically evaluating outcomes in these patients.

Stulak and colleagues retrospectively reviewed the records of patients who had LVAD reoperations between October 1996 and December 2011. There were a total of 422 LVAD implants.

Of the 45 initial device exchanges, 34 were men and the average age was 58 (spanning from 29 to 80). The median time to first exchange was 15 months.

Fifty-eight percent of the devices were continuous flow at the primary implant and 42% were pulsatile.

The indications for exchange included:

• Mechanical failure -- 44%
• Thrombus/hemolysis -- 31%
• Major driveline infection -- 22%
• Other -- 3%

Most of the mechanical failure occurred in the pulsatile devices, while all of the thrombus/hemolysis occurred in the continuous flow devices. Three-quarters of the initially exchanged devices were continuous flow.

"Although the continuous flow devices are most often preferred today, they are more prone to thrombus or hemolysis," Stulak told 乌鸦传媒.

"The good news is that we can be aggressive about deciding to exchange a device, particularly for driveline infections, which generally progress into pocket infections," he said.

The overall survival of the 422 LVAD patients was 83% at one year and 61% at three years. When broken down by pump style, those with the continuous flow LVADs had significantly better survival at three years.

The same was true for device exchange. At six months after the first reoperation, survival was 92%. At one year, it dropped to 89%, and then to 60% at 18 months. Survival among those with both types of LVADs was similar out to about six months when survival for those with the pulsatile devices began to significantly decline relative to the continuous flow devices.

The overall hazard ratio for survival after the first exchange was 0.60. For continuous flow versus pulsatile devices, the hazard ratios were 0.42 versus 0.24.

Stulak concluded that device exchange -- including multiple exchanges per patient -- can be performed with low early mortality.

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