Daily Cardiology Research Analysis
Three studies advance structural and preventive cardiology: left atrial appendage occlusion (LAAO) during cardiac surgery reduced cardioembolic stroke features, disability, and 30-day mortality; a large multicenter TEER registry identified a postprocedural left atrial v-wave >25 mmHg as a strong predictor of 3-year mortality; and elevated lipoprotein(a) independently predicted stenotic structural valve degeneration of aortic bioprostheses with a dose–response relationship.
Summary
Three studies advance structural and preventive cardiology: left atrial appendage occlusion (LAAO) during cardiac surgery reduced cardioembolic stroke features, disability, and 30-day mortality; a large multicenter TEER registry identified a postprocedural left atrial v-wave >25 mmHg as a strong predictor of 3-year mortality; and elevated lipoprotein(a) independently predicted stenotic structural valve degeneration of aortic bioprostheses with a dose–response relationship.
Research Themes
- Perioperative stroke prevention via LAAO in atrial fibrillation
- Hemodynamic targets after mitral TEER (left atrial v-wave) and outcomes
- Biomarker-driven risk of bioprosthetic valve degeneration (lipoprotein(a))
Selected Articles
1. Stroke Mechanism and Severity After Left Atrial Appendage Occlusion: Insights From the LAAOS III Randomized Clinical Trial.
In a post hoc analysis of the LAAOS III RCT, adding surgical LAAO to standard cardiac surgery in AF patients reduced disability (lower mRS), 30-day post-stroke mortality, cortical infarcts, and presumed cardioembolic strokes among those who sustained an ischemic stroke. These data mechanistically support LAAO’s stroke prevention benefits beyond simple incidence reduction.
Impact: Clarifies that LAAO not only lowers stroke incidence but also shifts mechanism away from cardioembolism and improves early outcomes, reinforcing its role during concomitant cardiac surgery in AF.
Clinical Implications: For AF patients undergoing cardiac surgery, concomitant LAAO should be considered to reduce cardioembolic stroke features, disability, and early mortality. Stroke teams can anticipate fewer cortical, cardioembolic-phenotype infarcts after LAAO.
Key Findings
- LAAO reduced modified Rankin Scale scores at day 7/discharge (common OR 0.80, 95% CI 0.65-0.99).
- Lower 30-day mortality after stroke with LAAO (16.5% vs 20.1%; HR 0.55, 95% CI 0.31-0.97).
- Fewer cortical infarcts on imaging (46.2% vs 61.3%; −15.2%, 95% CI −26.7% to −3.7%).
- Lower proportion of presumed cardioembolic ischemic strokes (42.9% vs 57.9%; −15.1%, 95% CI −26.5% to −3.7%).
Methodological Strengths
- Secondary analysis nested in a large, multicenter randomized trial (LAAOS III) with adjudicated outcomes.
- Robust imaging-based phenotyping of stroke subtypes and standardized functional outcome (mRS).
Limitations
- Post hoc exploratory nature; not randomized for stroke severity endpoints.
- Findings limited to AF patients undergoing cardiac surgery; generalizability to percutaneous LAAO or non-surgical cohorts is uncertain.
Future Directions: Prospective, pre-specified analyses comparing LAAO vs no LAAO on stroke phenotypes; mechanistic imaging and embolic source studies; applicability to percutaneous LAAO populations.
2. Impact of Left Atrial v-Wave Following Mitral Edge-to-Edge Repair on Survival: The MITRA-PRO Registry.
In 1,487 TEER patients, increased postprocedural left atrial v-wave was associated with worse 3-year survival, with a threshold v-wave >25 mmHg predicting higher mortality. Patients achieving v-wave ≤25 mmHg had the lowest mortality, supporting v-wave as an actionable hemodynamic target during TEER optimization.
Impact: Defines a clear, measurable intraprocedural hemodynamic target (v-wave ≤25 mmHg) linked to long-term survival, enabling procedural guidance and residual MR assessment beyond imaging alone.
Clinical Implications: During TEER, aim to reduce the left atrial v-wave to ≤25 mmHg via clip optimization, adjunctive maneuvers, or addressing residual MR. Incorporate v-wave into multimodal residual MR assessment for risk stratification.
Key Findings
- Post-TEER increased v-wave associated with reduced 3-year survival.
- A v-wave threshold >25 mmHg predicted higher 3-year mortality by ROC analysis.
- Patients with postprocedural v-wave ≤25 mmHg had significantly lower 3-year mortality than those >25 mmHg.
Methodological Strengths
- Large-scale, multicenter registry with standardized hemodynamic assessment.
- Clear clinical endpoint (3-year mortality) and data-driven threshold identification.
Limitations
- Observational design precludes causal inference; residual confounding possible.
- Details of concomitant therapies and device iterations may influence v-wave and outcomes.
Future Directions: Prospective studies testing v-wave–guided TEER optimization strategies; integration with imaging and pulmonary vein flow to refine residual MR assessment; evaluate impact on hospitalization and quality of life.
3. Lipoprotein(a) and long-term structural valve degeneration of aortic bioprostheses.
In 174 patients after bioprosthetic AVR with 7.3 years median follow-up, elevated Lp(a) independently predicted long-term SVD, particularly stenotic/mixed phenotypes, with a linear dose–response (13% higher risk per 25 nmol/L). No association was seen with regurgitant SVD, positioning Lp(a) as a phenotype-specific biomarker and therapeutic target.
Impact: Links a modifiable biomarker to prosthetic valve stenotic degeneration with dose–response, generating a testable hypothesis for Lp(a)-lowering therapies to enhance bioprosthesis durability.
Clinical Implications: Consider measuring Lp(a) in patients receiving or following bioprosthetic AVR to refine long-term SVD risk, particularly for stenotic/mixed phenotypes, and to inform surveillance intensity and candidacy for emerging Lp(a)-lowering agents.
Key Findings
- Elevated Lp(a) (>125 nmol/L) associated with higher overall SVD risk (SHR 2.06, 95% CI 1.09-3.91).
- Stronger association with stenotic/mixed SVD phenotypes (adjusted SHR 3.00, 95% CI 1.48-6.07).
- No association with regurgitant SVD (SHR 0.85, 95% CI 0.19-3.92).
- Linear dose–response: each 25 nmol/L increase in Lp(a) conferred 13% higher risk.
Methodological Strengths
- Longitudinal follow-up with repeated echocardiography (1,372 studies) and VARC-3 SVD definitions.
- Competing risk modeling (Fine–Gray) and spline analyses capturing dose–response.
Limitations
- Single-center cohort with modest sample size; residual confounding possible.
- Observational design cannot confirm causality or therapeutic benefit of Lp(a) lowering.
Future Directions: Prospective multicenter validation and randomized trials testing Lp(a)-lowering therapies (e.g., antisense/siRNA) for preventing stenotic SVD; mechanistic imaging (CT calcium) and histopathology to link Lp(a) to leaflet calcification.