Page 12 - Journal of Structural Heart Disease Volume 2, Issue 1

Review Article 6
Figure 3. WATCHMAN e cacy data (PROTECT AF). Panel A. Primary e cacy. At 2621 patient-years of follow up, the WATCHMAN device met criterion for superiority compared to warfarin therapy for the combined endpoint of cardiovascular/unexplained death, stroke, or systemic embolism (2.3 events per 100 patient-years versus 3.8 per 100 patient years; RR 0.6; 95% CrI 0.41 to 1.05; posterior probability of 96%) [45]. Panel B. All-cause mortality. At 2621 patient-years of follow up, the WATCHMAN device was superior with regard to all-cause mortality (3.2% versus 4.8%; RR 0.66; 95%CrI, 0.45 to 0.98) and cardiovascular mortality (1 per 100 patient years versus 2.4 per 100 patient-years; RR 0.4; 95%CrI, 0.21 to 0.72) compared with warfarin [45].
alone was continued thereafter.
The initial 1065 patient-years follow-up demon-
strated WATCHMAN as noninferior to warfarin for the combined e cacy primary endpoint of cardio- vascular/unexplained death, stroke, or systemic em- bolism. The primary e cacy endpoint event rate was 3.0 per 100 patient-years (95% credible interval [CrI] 1.9–4.5) in the WATCHMAN group and 4.9 per 100 patient-years (95% CrI 2.8–7.1) in the warfarin group (rate ratio [RR] 0.62, 95% CrI 0.35–1.25). Anal- ysis at 1588 patient-years con rmed the noninferior- ity of WATCHMAN compared to warfarin with regard to the primary e cacy endpoint of cardiovascular/ unexplained death, stroke, or systemic embolism (RR 0.71, 95% CrI 0.44 to 1.30) [44]. At 2621 patient-years of follow up, the WATCHMAN device met criterion for superiority compared to warfarin therapy for the combined endpoint (2.3 events per 100 patient-years versus 3.8 per 100 patient years; RR 0.6; 95% CrI 0.41 to 1.05; posterior probability of 96%) [45]. Addition- ally, the WATCHMAN device was superior with regard to all-cause mortality (3.2% versus 4.8%; RR 0.66; 95%CrI, 0.45 to 0.98) and cardiovascular mortality (1 per 100 patient years versus 2.4 per 100 patient-years; RR 0.4; 95% CrI, 0.21 to 0.72) compared with warfarin (Figure 3). Hemorrhagic stroke rates were signi cant- ly lower in the WATCHMAN group (0.2% versus 1%; RR 0.18; 95% CrI, 0.04 to 0.6).
The PROTECT AF study demonstrated that the WATCHMAN device could be successfully implant- ed. It was successfully implanted in 88% (408/463) of patients randomized to the WATCHMAN group and in 91% (408/449) of patients in whom implant was attempted. At the 45-day TEE, 86% (349/408) of patients were able to discontinue warfarin. At the 6-month TEE, 92% (355/408) of patients were able to discontinue warfarin. While long-term follow up of PROTECT AF has demonstrated sustained e cacy and con rmed long-term safety, acute safety events in PROTECT AF were an initial concern. Primary safety events at 18 months occurred at a higher rate in the WATCHMAN group compared to the warfarin group (RR 1.69, 95% CrI 1.01–3.19). The majority of safety events in the WATCHMAN group (55%, 27out of 49) occurred on the day of the procedure. This contrasts to the warfarin group, which had half (8 out of 16) occur between day 45 and 1 year. The most frequent primary complications were directly procedure re- lated including serious pericardial e usion and pro- cedure-related ischemic stroke. No peri-procedural death or long-term disability occurred within this or in any WATCHMAN clinical trial. In further analysis, there was a signi cant decline in procedure related safety events within 7 days of the procedure between the rst and second halves of the PROTECT AF trial and the Continued Access Protocol Registry (CAP)
Journal of Structural Heart Disease, February 2016
Volume 2, Issue 1:1-14