Improving outcomes of surgery for acute type A aortic dissection.

Background. It remains equivocal if acute type A aortic dissection (ATAAD) surgical outcomes are improving. We analyzed current outcome trends to evaluate improvements and to identify predicting variables. Methods. From 2015 to 2020, 204 patients underwent surgery for ATAAD and were divided into recent (n = 102) and earlier (n = 102) groups. Uni- and multivariable statistical analysis was performed to identify predictors of 30-day mortality. Results. Thirty-day mortality decreased significantly in the recent group (3.9% vs 14.6%, p = .014). Prevalence of neurological insult also decreased significantly (13% vs 25%, p = .028). Other major complications remained unchanged. There was no statistically significant difference in overall 30-day mortality between low-volume vs high-volume surgeons (12.3% vs 7.3%, p = .21). The number of surgeons performing ATAAD procedures decreased from nine in 2015 to five in 2020. Preoperative lactate (OR 1.24, 95%CI 1.03-1.51), dissection of any arch vessel (OR 14.2, 95%CI 1.79-113), non-normal left ventricular ejection fraction (OR 12.5, 95%CI 2.54-61.6), biological composite graft (OR 19.1, 95%CI 2.75-133), concomitant coronary artery bypass grafting (OR 38.8, 95%CI 2.91-517) and intraoperative adverse event (OR 9.5, 95%CI 2.22-40.9) were statistically significant independent predictors of mortality. Conclusions. Early outcomes after ATAAD improved in the most recent experience. Part of the explanation may be fewer surgeons performing more procedures annually, a relatively conservative approach to the extent of aortic resection and ensuring adequate cerebral protection. Major complications remain prevalent and require attention to be further reduced.

Type A Aortic Dissection Repair in Patients With Prior Cardiac Surgery.

BACKGROUND: Emergency surgery for acute type A aortic dissection in patients with previous cardiac surgery is controversial. This study aimed to evaluate the association between previous cardiac surgery and outcomes after surgery for acute type A aortic dissection, to appreciate whether emergency surgery can be offered with acceptable risks. METHODS: All patients operated on for acute type A aortic dissection between 2005 and 2014 from the Nordic Consortium for Acute Type A Aortic Dissection database were eligible. Patients with previous cardiac surgery were compared with patients without previous cardiac surgery. Univariable and multivariable statistical analyses were performed to identify predictors of 30-day mortality and early major adverse events (a secondary composite endpoint comprising 30-day mortality, perioperative stroke, postoperative cardiac arrest, or de novo dialysis). RESULTS: In all, 1159 patients were included, 40 (3.5%) with previous cardiac surgery. Patients with previous cardiac surgery had higher 30-day mortality (30% vs 17.8%, P = .049), worse medium-term survival (51.7% vs 71.2% at 5 years, log rank P = .020), and higher unadjusted prevalence of major adverse events (52.5% vs 35.7%, P = .030). In multivariable analysis, previous cardiac surgery was not associated with 30-day mortality (odds ratio 0.78; 95% CI, 0.30-2.07; P = .624) or major adverse events (odds ratio 1.07; 95% CI, 0.45-2.55, P = .879). CONCLUSIONS: Major adverse events after surgery for acute type A aortic dissection were more frequent in patients with previous cardiac surgery. Previous cardiac surgery itself was not an independent predictor for adverse events, although the small sample size precludes definite conclusions. Previous cardiac surgery should not deter from emergency surgery.

Temperature effects on incidence of surgery for acute type A aortic dissection in the Nordics.

We aimed to investigate a hypothesised association between daily mean temperature and the risk of surgery for acute type A aortic dissection (ATAAD). For the period of 1 January 2005 until 31 December 2019, we collected daily data on mean temperatures and date of 2995 operations for ATAAD at 10 Nordic cities included in the Nordic Consortium for Acute Type A Aortic Dissection (NORCAAD) collaboration. Using a two-stage time-series approach, we investigated the association between hot and cold temperatures relative to the optimal temperature and the rate of ATAAD repair in the selected cities. The relative risks (RRs) of cold temperatures (≤-5°C) and hot temperatures (≥21°C) compared to optimal temperature were 1.47 (95% CI: 0.72-2.99) and 1.43 (95% CI: 0.67-3.08), respectively. In line with previous studies, we observed increased risk at cold and hot temperatures. However, the observed associations were not statistically significant, thus only providing weak evidence of an association.

Impact of national holidays and weekends on incidence of acute type A aortic dissection repair.

Previous studies have demonstrated that environmental and temporal factors may affect the incidence of acute type A aortic dissection (ATAAD). Here, we aimed to investigate the hypothesis that national holidays and weekends influence the incidence of surgery for ATAAD. For the period 1st of January 2005 until 31st of December 2019, we investigated a hypothesised effect of (country-specific) national holidays and weekends on the frequency of 2995 surgical repairs for ATAAD at 10 Nordic cities included in the Nordic Consortium for Acute Type A Aortic Dissection (NORCAAD) collaboration. Compared to other days, the number of ATAAD repairs were 29% (RR 0.71; 95% CI 0.54-0.94) lower on national holidays and 26% (RR 0.74; 95% CI 0.68-0.82) lower on weekends. As day of week patterns of symptom duration were assessed and the primary analyses were adjusted for period of year, our findings suggest that the reduced surgical incidence on national holidays and weekends does not seem to correspond to seasonal effects or surgery being delayed and performed on regular working days.

Once after a full moon: acute type A aortic dissection and lunar phases.

OBJECTIVES: Acute type A aortic dissection (ATAAD) is a rare but severe condition, routinely treated with emergent cardiac surgery. Many surgeons have the notion that patients with ATAAD tend to come in clusters, but no studies have examined these observations. This investigation was undertaken to study the potential association between the lunar cycle and the incidence of ATAAD. METHODS: We collected information on 2995 patients who underwent ATAAD surgery at centres from the Nordic Consortium for Acute Type A Aortic Dissection collaboration. We cross-referenced the time of surgery with lunar phase using a case-crossover design with 2 different definitions of full moon (>99% illumination and the 7-day full moon period). RESULTS: The period when the moon was illuminated the most (99% definition) did not show any significant increase in incidence for ATAAD surgery. However, when the full moon period was compared with all other moon phases, it yielded a relative risk of 1.08 [95% confidence interval (CI) 1.00-1.17, P = 0.057] and, compared to waxing moon, only the relative risk was 1.11 (95% CI 1.01-1.23, P = 0.027). The peak incidence came 4-6 days after the moon was fully illuminated. CONCLUSIONS: This study found an overrepresentation of surgery for ATAAD during the full moon phase. The explanation for this is not known, but we speculate that sleep deprivation during full moon leads to a temporary increase in blood pressure, which in turn could trigger rupture of the aortic wall. While this finding is interesting, it needs to be corroborated and the clinical implications are debateable.

A randomized prospective multicenter trial for stroke prevention by prophylactic surgical closure of the left atrial appendage in patients undergoing bioprosthetic aortic valve surgery--LAA-CLOSURE trial protocol.

Patients undergoing surgical aortic valve replacement (SAVR) are at high risk for atrial fibrillation (AF) and stroke after surgery. There is an unmet clinical need to improve stroke prevention in this patient population. The LAA-CLOSURE trial aims to assess the efficacy and safety of prophylactic surgical closure of the left atrial appendage for stroke and cardiovascular death prevention in patients undergoing bioprosthetic SAVR. This randomized, open-label, prospective multicenter trial will enroll 1,040 patients at 13 European sites. The primary endpoint is a composite of cardiovascular mortality, stroke and systemic embolism at 5 years. Secondary endpoints include cardiovascular mortality, stroke, systemic embolism, bleed fulfilling academic research consortium (BARC) criteria, hospitalization for decompensated heart failure and health economic evaluation. Sample size is based on 30% risk reduction in time to event analysis of primary endpoint. Prespecified reports include 30-day safety analysis focusing on AF occurrence and short-term outcomes and interim analyses at 1 and 3 years for primary and secondary outcomes. Additionally, substudies will be performed on the completeness of the closure using transesophageal echocardiography/cardiac computed tomography and long-term ECG recording at one year after the operation.

ABO blood group does not impact incidence or outcomes of surgery for acute type A aortic dissection.

Objectives. To evaluate the distribution and impact of ABO blood groups on postoperative outcomes in patients undergoing surgery for acute type A aortic dissection (ATAAD). Design. A total of 1144 surgical ATAAD patients from eight Nordic centres constituting the Nordic consortium for acute type A aortic dissection (NORCAAD) were analysed. Blood group O patients were compared to non-O subjects. The relative frequency of blood groups was assessed with t-distribution, modified for weighted proportions. Multivariable logistic regression was performed to identify independent predictors of 30-day mortality. Cox regression analyses were performed for assessing independent predictors of late mortality. Results. There was no significant difference in the proportions of blood group O between the study populations in the NORCAAD registry and the background population (40.6 (95% CI 37.7-43.4)% vs 39.0 (95% CI 39.0-39.0)%). ABO blood group was not associated with any significant change in risk of 30-day or late mortality, with the exception of blood group A being an independent predictor of late mortality. Prevalence of postoperative complications was similar between the ABO blood groups. Conclusions. In this large cohort of Nordic ATAAD patients, there were no associations between ABO blood group and surgical incidence or outcomes, including postoperative complications and survival.

Evolution of Left Ventricular Size in Late Survivors of Surgery for Hypoplastic Left Heart Syndrome.

BACKGROUND: Aortic atresia and mitral atresia are predictors of adverse events in early life in patients with hypoplastic left heart syndrome, but it is unclear whether late outcomes are also affected, and whether this impact is related to a small hypertrophied left ventricle (LV) that impairs right ventricle (RV) function. METHODS: Thirty patients with hypoplastic left heart syndrome surviving with a Fontan procedure were identified. Follow-up echocardiograms were available at birth, before the Fontan procedure, and several years after. Mean follow-up time was 10.9 ± 3.1 years. Measurements included interventricular septum thickness and ventricular length. The LV/RV length ratio at birth was calculated, and its impact on later LV and septal growth was examined. The primary endpoint was a composite of death, transplantation, or Fontan takedown. RESULTS: A cutoff LV/RV length ratio of 0.55 was identified: length ratio was 0.55 or less in group A (18 patients) and more than 0.55 in group B (12 patients) The LV/RV length ratio and interventricular septum thickness decreased over time in group A while remaining static in group B. The LV length at birth did not affect late adverse outcomes (hazard ratio 2.7, 95% confidence interval: 0.31 to 23.4, p = 0.37), whereas aortic atresia and mitral atresia were the most potent predictors of death or transplantation or takedown (hazard ratio 8.5, 95% confidence interval: 1.2 to 57.7, p = 0.029). CONCLUSIONS: Patients with aortic atresia and mitral atresia have worse outcomes even after Fontan independently of a small, thick, hypertrophied LV. The most severely hypoplastic LVs do not grow proportionally as much as the RVs.

Outcomes of aortic arch repair with extended (≥ 90 minutes) antegrade cerebral perfusion.

OBJECTIVES: To analyze outcomes with extended duration of antegrade cerebral perfusion (ACP) during hypothermic circulatory arrest (HCA) for total arch repair (TAR). DESIGN: Retrospective study of consecutive patients undergoing TAR with HCA and ACP. Patients were divided into group A (ACP ≥ 90 min, n = 12) and group B (ACP < 90 min, n = 17) and compared regarding in-hospital mortality and neurological complications (primary outcome measures) and major complications, biochemical markers of organ damage, and blood product use (secondary outcome measures). Complications were analyzed according to standards of the International Aortic Arch Surgery Study Group. RESULTS: Overall in-hospital mortality was 4/29 (14%); 1/12 (8.3%) in group A versus 3/17 (18%) in group B, p = 0.62. No grade-V (lethal) neurological complication occurred, but five patients (all in group B) had grade-IV neurological complications: one general and two each focal and spinal neurological deficit (p = 0.047, overall). Prevalence of grade-II (temporary) general neurological deficit was 17% (group A) versus 27% (group B), p = 0.66. None of the patients suffered ≥ grade-IV respiratory or renal complications. Other complications, biochemical markers, and blood product usage were not significantly different. CONCLUSION: Outcomes in TAR with HCA and extended (≥ 90 min) three-vessel ACP were encouraging and could be contemplated with anticipated time-consuming TAR.