A recent Cardiothoracic Surgery digest,
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Study Type: Retrospective cohort study (administrative health data)

Key Question: Does inter-operator variation in CABG referral rates among interventional cardiologists affect long-term patient outcomes?

Key Findings:

• CABG referral rates varied 13-fold across 40 interventionalists (2.03%–26.4%), with substantial operator-level variation independent of hospital factors (ICC 0.358)
• Higher operator CABG rates correlated with lower PCI utilisation (R=−0.60) and less extensive PCI (R=−0.52)
• Among 73,603 revascularised patients, higher operator CABG rate was associated with significantly fewer repeat revascularisations (HR 0.075), with no difference in mortality or MACE

Clinical Relevance: This supports the case for consistent multidisciplinary Heart Team decision-making in UK catheter laboratories, where operator-driven variation in CABG referral may compromise revascularisation durability without clinical justification.

Limitations: Observational design using administrative data from a single Canadian province limits causal inference and generalisability to NHS practice.

Study Type: Retrospective cohort study

Key Question: What are the characteristics, surgical management, and long-term outcomes of mitral valve (MV) anomalies in patients undergoing biventricular repair for TGA?

Key Findings:

• MV anomalies occurred in 3.3% of TGA {S,D,D} repairs (52/1590); anterior mitral cleft was predominant (88%), with subvalvular abnormalities in 60%
• Overall survival was 92.3% at 1 year and 88.3% at 20 years (mean follow-up 11.2 years); freedom from late MV surgery was 82.8% at 20 years
• Concomitant MV repair at index surgery (n=10) led to no subsequent MV reintervention; six patients required late MV surgery, all having had no mitral intervention at initial repair

Clinical Relevance: For UK congenital cardiac surgeons, this supports a selective strategy for MV repair at arterial switch — intervening only for significant regurgitation or obstructive subvalvular pathology, avoiding routine prophylactic repair.

Limitations: Single-centre retrospective design over 30 years risks significant era-related surgical heterogeneity.

Study Type: Retrospective cohort study

Key Question: How do specific experience, cross-procedural (analogy-based) learning, and cumulative volume influence risk-adjusted outcomes across CABG, AVR, and MVR?

Key Findings:

• Higher procedure-specific quarterly volume was associated with lower 30-day RAMR for CABG (−0.49 percentage points; 95% CI −0.88 to −0.10; p=0.014)
• Prior-quarter volumes of technically related procedures (AVR/MVR) showed significant non-linear cross-procedural effects on CABG RAMR, suggesting analogy-based learning transfer
• Greater cumulative MVR experience significantly reduced risk-adjusted re-thoracotomy rate (−0.295; 95% CI −0.55 to −0.03; p=0.028); no volume-outcome associations identified for AVR

Clinical Relevance: These findings support procedure-specific caseload planning in UK cardiac surgery units, with implications for surgical rostering, training programme design, and low-volume centre decision-making.

Limitations: Single-centre German dataset limits generalisability, and confounding by case complexity or team-level factors cannot be fully excluded.

Study Type: Retrospective cohort study

Key Question: Do preoperative CPET variables independently predict 30-day postoperative complications following anatomical lung resection for NSCLC?

Key Findings:

• 30-day complication rate was 9.4% (33/353); BMI, FEV1/FVC, and VE/VCO2 slope were independent multivariable predictors, though effect sizes were modest (ORs 0.86, 0.94, and 1.06 respectively)
• Individual CPET variables showed poor discriminative accuracy: VO2peak AUC 0.52, anaerobic threshold AUC 0.59, VE/VCO2 slope AUC 0.40
• Standard CPET cut-offs were non-informative for risk stratification in this cohort

Clinical Relevance: This challenges the routine use of CPET as a stand-alone surgical gatekeeper in UK thoracic practice, supporting its use as one component of a multimodal risk assessment rather than a decisive threshold tool.

Limitations: Single-centre retrospective design with a relatively small complication cohort (n=33) limits statistical power and generalisability.

Study Type: Nationwide cross-sectional survey

Key Question: What conduit types are currently used for right ventricle-to-pulmonary artery (RV-PA) reconstruction in Japan, and what criteria drive surgeon selection?

Key Findings:

• Handmade ePTFE valved conduits dominate practice (80.7% of 926 cases across 52 institutions), with bovine jugular vein conduits (7.5%) and homografts (1.1%) used rarely
• "Functional durability and performance" was the top surgeon priority (median score 4.00), with an expected conduit lifespan of 10 years — a target current conduits generally fail to meet
• Homograft use is near-absent due to the absence of an organised national supply system in Japan

Clinical Relevance: UK surgeons benefit from a comparatively robust homograft supply via NHS Blood and Transplant; this survey highlights the performance gap that would exist without it and informs ongoing conduit development relevant to all congenital programmes.

Limitations: Low response rate (41.2%) risks institutional selection bias and limits national representativeness.

Study Type: Retrospective cohort study

Key Question: Does perfusion interval independently predict myocardial injury in minimally invasive mitral valve surgery using blood-enriched modified del Nido cardioplegia, and is this modified by aortic cross-clamp (ACC) duration?

Key Findings:

• Perfusion interval lost its association with peak troponin I after multivariate adjustment (coefficient −0.0006, 95% CI −0.0109 to 0.0097; p=0.913)
• ACC time remained an independent predictor of troponin rise (coefficient 0.0099, 95% CI 0.0013–0.0185; p=0.024), with exploratory data suggesting non-linear injury acceleration beyond 80 minutes
• Single-dose cardioplegia appeared adequate when ACC time ≤90 minutes; no associations reached significance for composite adverse outcomes

Clinical Relevance: Supports a context-dependent cardioprotection strategy for minimally invasive mitral surgery, suggesting single-dose del Nido cardioplegia is sufficient for procedures within 90-minute ACC time — relevant to UK units adopting extended cardioplegia intervals.

Limitations: Retrospective single-centre design limits generalisability; the 80-minute threshold is exploratory and underpowered for firm clinical translation.

Study Type: Retrospective multicentre cohort study

Key Question: What are the mid-term clinical and echocardiographic outcomes of aortic valve neocuspidization (AVNeo) in a real-world population?

Key Findings:

• 30-day mortality was 3.0% across 672 patients at 16 centres, in a cohort notable for advanced age and significant comorbidity burden
• Overall survival was 91.7% at 1 year and 79.5% at 5 years; freedom from reoperation was 99.4% at 1 year and 96.5% at 5 years
• Transvalvular gradients, valve area, and ventricular function remained stable from 1 to 7 years post-operatively, with no evidence of progressive structural deterioration

Clinical Relevance: AVNeo is an increasingly considered alternative to conventional bioprosthetic replacement in UK practice; this dataset provides the largest real-world durability evidence to date supporting its reproducibility across institutions.

Limitations: Retrospective design with inherent selection bias and no comparator arm against established surgical or transcatheter alternatives.

Study Type: Retrospective secondary analysis of a single-centre prospective cohort

Key Question: Does the postoperative CRP resolution pattern differ between cardiac surgery patients who develop POAF and those who do not?

Key Findings:

• POAF occurred in 51% of 319 patients; slower CRP decline between POD3–10 was independently associated with POAF (OR 1.71, p=0.046)
• IL-10 levels were significantly higher in POAF patients (mean ratio 1.28, p<0.001), suggesting a prolonged inflammatory state
• POAF patients had longer ICU stays and time to extubation, independently associated with the slower CRP trajectory

Clinical Relevance: In NHS cardiac surgery units where POAF drives significant postoperative resource use, CRP kinetics may offer a straightforward biomarker to risk-stratify patients or identify those warranting targeted anti-inflammatory strategies.

Limitations: Single-centre secondary analysis limits generalisability, and the observational design prevents causal inference between inflammation trajectory and POAF.