The PINNACLE FLX study's one-year results showed that the Watchman FLX device provided effective appendage closure in all patients with few early adverse events. However, its efficacy in reducing the risk of outcomes such as stroke was still not clear. The results of the second year of the study were presented at the TVT2021.
At 29 US sites, the PINNACLE FLX trial enrolled 400 patients with atrial fibrillation (AF). The mean age of the study population was 74 years, and 36% of them were women. The patients had a mean CHA2DS2-VASc score of 4.2 and a mean HAS-BLED score of 2.0. A history of major bleeding or predisposition to bleeding was present in 33% of patients. Transesophageal echocardiography (TEE) was used to image all patients at 45 days, 6 months, and 1 year.
At 1 year, effective appendage seal and low rates of early adverse events (0.5% at 7 days per discharge) were reported. The rate of stroke or systemic embolism at one year was 3.1%. In the second year of follow-up, only one additional ischemic event was recorded.
Compared to the first year of study, adverse events were less in the second year. All-cause mortality, cardiovascular mortality, any type of stroke, ischemic stroke, hemorrhagic stroke, and systemic embolism was reported in 9.3%, 5.5%, 3.4%, 3.1%, 0.3%, and 0.3% of patients, respectively, over a two-year period. Major bleeding (BARC type 3 or 5) occurred at a rate of 8.2% in the first year and 1.9% in the second. All the bleeding events reported in the second year were classified as BARC 3. Only 1% of the pericardial effusion cases required surgery or pericardiocentesis.
The findings of the PINNACLE FLX trial demonstrated a low rate of stroke and systemic embolism in patients with atrial fibrillation (AF) as an alternative to the conventional chronic oral anticoagulation treatment.