Two recent studies are forcing an important conversation in cardiology – some of the field’s most common procedures may not be as clearly beneficial as open-label data originally suggests.
- First, an eight-trial meta-analysis found that left atrial appendage closure (LAAC) was no better than oral anticoagulation for preventing stroke overall.
- Then, PVI-SHAM-AF found catheter ablation for AFib didn’t significantly beat a sham procedure for improving AFib-related quality of life at six months.
Let’s start with PVI-SHAM-AF, since it’s more contested. Researchers randomized 262 patients to either the clinician’s choice of ablation (RF, Cryo, or PFA) or a “sham” procedure where patients were sedated and given IV sheaths but not catheterized, finding that…
- Quality of life AFEQT scores (a scale 0-100) improved 19.8 points with ablation versus 15.7 with sham without statistical significance.
- Yet, ablation clearly led to freedom from AFib (73% vs. 52% for sham).
- That means the observed effect of a procedure isn’t the same as its specific effect. Much of what patients felt, they felt after a sham too.
But EPs are pushing back on PVI-SHAM-AF’s results with online comments clarifying:
- Two earlier sham-controlled trials already showed clear benefit, making PVI-SHAM-AF the possible outlier, not the verdict.
- Selection bias matters too, with roughly 80% of PVI-SHAM-AF’s invited patients declining to participate, leading to a less-symptomatic study population and more placebo effect.
The LAAC meta-analysis points the same way from a different angle. To determine LAAC’s real-world efficacy, researchers examined 7.4k patients who either received LAAC or oral anticoagulation with a focus on their long-term stroke and major bleeding rates.
- LAAC’s overall stroke (IRR: 1.08) and major bleeding impact (IRR: 0.96) were similar to anticoagulation.
- However, LAAC was associated with higher ischemic stroke rates (IRR: 1.34) but lower non-procedural bleeding (IRR: 0.73).
- Thus, the study’s authors say the data doesn’t support LAAC as routine first-line stroke prevention.
Do these two studies mean that these cardiac interventions are in trouble? Not exactly.
- Rather these two trials keep shrinking the obviousness of positive effects that looked meaningful in open-label data.
- As a result, defending a procedure on the basis that it “improves symptoms” or “successfully closes the appendage” may not be enough to justify it.
The Takeaway
The evidentiary bar is rising for some cardiac procedures, and the exact benefits of a procedure like ablation or LAAC still need exploration. For the cardiac medtech industry that means proving a device’s value against rigorous study design and patient selection. For clinicians it means more questions to consider.
