Outcomes of Elective Aortic Hemiarch Reconstruction for Aneurysmal Disease in the Elderly

Impact of planned concomitant coronary artery bypass grafting on risk of major adverse cardiovascular events in elective aortic hemiarch surgery

BACKGROUND

Hemiarch replacement of the ascending aorta has become routine in many aortic centers. While the addition of coronary bypass does not add a lot of time to the procedure, it carries with more significant comorbidities. We hypothesize that the addition of CABG carries a higher risk of complication than hemiarch alone.

METHODS

This is a single-center, retrospective cohort study of 419 patients undergoing elective hemiarch surgery between February 2010 and May 2023. Patients were categorized into concomitant CABG (n = 42) and non-CABG (n = 379) groups. Perioperative variables and outcomes were analyzed. Both univariate and multivariate logistic regressions were used to identify predictors for MACE.

RESULTS

Of 419 patients, 42 (10%) patients received adjunctive CABG. This group was older (68.1 vs. 60.4 years, p < 0.001) with more comorbidities associated with coronary artery disease (CAD), such as hypertension (92.9% vs. 59.2%, p < 0.001), type 2 diabetes (33.3% vs. 8.8%, p < 0.001), and atrial fibrillation (19% vs. 5.8%, p = 0.006). CABG patients had longer cardiopulmonary bypass (158 vs. 131 min, p < 0.001) and aortic cross-clamp (115.5 vs. 95 min, p < 0.001) times and required more intraoperative blood products, FFP (4 vs. 2 units, p = 0.010) and platelets (2 vs. 1 units, p < 0.001). Postoperative complications, including arrhythmia (40.5% vs. 21.8%, p = 0.012), mechanical circulatory support (11.9%, 1.9%, p = 0.004), acute kidney injury (16.7% vs. 0.5%, p < 0.001), infection (11.9% vs. 3.7%, p = 0.032), mortality (9.5% vs. 0.5%, p = 0.001), stroke (9.5% vs. 2.1%, p = 0.024), and the composite outcome- MACE (21.4% vs. 2.9%, p < 0.001) were higher in the CABG group. Multivariate analysis identified the number of bypassed vessels (OR: 2.23, CI 1.33-3.69, p = 0.002), age (OR: 1.07, CI: 1.02-1.13, p = 0.006), and female gender (OR: 3.53, CI: 1.31-9.64, p = 0.012) as significant risk factors for MACE.

CONCLUSIONS

Concomitant CABG may increase the risk of MACE compared to other patients undergoing hemiarch. These data argue that the risk may be higher for concomitant CABG but should still undergo revascularization. Future research should focus on preoperative optimization, operative strategies, and sex-specific risk factors to improve elective hemiarch replacement outcomes.

Revisiting ascending aortic resection in the elective valve-sparing root replacement: assessing the benefits and necessity of hemiarch replacement at three centres†

OBJECTIVE

The aim of this study was to determine the indication and optimal timing for performing a hemiarch procedure in patients undergoing valve-sparing root replacement (VSRR).

METHODS

We conducted a retrospective study on 986 patients undergoing VSRR at three tertiary care centres. Inclusion criteria were all patients undergoing elective VSRR. Exclusion criteria were age <18 years, Stanford type A dissection, dissection in the arch, total aortic arch replacement or previous aortic arch replacement. We performed propensity score matching in a 1:1 ratio. The primary end-point is a composite outcome that includes mortality, aortic arch reintervention, new aortic dissection during follow-up and cerebrovascular incidents within the first 30 days.

RESULTS

A total of 401 patients (41%) had a hemiarch replacement, while 585 (59%) did not. Root phenotype was present in 565 (57%). The mean follow-up time was 4.7 years (SD ± 4.6). In the matched population, there was no significant difference in the 10-year freedom from the composite outcome between the non-hemiarch and hemiarch groups (87.3% vs 85.0%, P > 0.999). Similarly, no difference was found for aortic reinterventions (P = 0.13) or survival (P = 0.5). This was also true for patients with heritable thoracic aortic disease. However, in patients with a bicuspid aortic valve, the intervention rate was significantly higher in the hemiarch group (10.8% vs 0%, P = 0.016). There was no significant difference in the 30-day incidence of cerebrovascular accidents between the groups (5% vs 2.7% in the hemiarch group, P = 0.117). Only the distal ascending diameter showed a tendency with better outcome over 45 mm for the hemiarch procedure; otherwise, we found no reliable cut-off values based on ascending length, diameter-to-height index or ascending length-to-height index.

CONCLUSIONS

Our findings conclusively demonstrate that concomitant hemiarch replacement does not increase the perioperative risk in young patients undergoing VSRR. However, concomitant replacement does not seem to protect from aortic reinterventions during medium-term follow-up.

Outcomes of acute type A aortic dissection repair in patients under the age of 75 versus 75 and older

OBJECTIVE

Elderly patients are less likely to undergo surgery for an acute type A aortic dissection (ATAAD). This study aims to understand the risks of surgical treatment in patients 75 and older.

METHODS

This was a retrospective study using an institutional database of patients who underwent ATAAD repair from 2007 to 2021. Outcomes were compared between patients <75 and patients ≥ 75. Logistic regression was performed for operative mortality, and Cox regression was performed for long-term mortality.

RESULTS

A total of 601 patients underwent surgery for ATAAD, 112 (18.6%) of whom were ≥75. Patients ≥75 were significantly more likely to undergo hemiarch replacement (vs total arch replacement) and concomitant CABG. Operative mortality was 16.1% in patients ≥75 versus 10.2% in those <75 (p = 0.078). On multivariable logistic regression, age ≥75 was not significantly associated with operative mortality (p = 0.068). Effect of age on long-term mortality was time-dependent: on Cox regression, being 75 or older and within one-year post-discharge was significantly associated with an increased hazard of death (time-dependent HR 4.56; 95% CI, 2.31-9.06; p < 0.001), while age was not associated with an increased hazard of death after the first postoperative year (p = 0.779).

CONCLUSION

Despite reduced survival during the first postoperative year among patients 75 years and older, operative mortality and late survival were similar across each group. By implication, age alone should not be a deterrent to operative intervention in ATAAD patients, even though further investigation is needed to determine opportunities for improving survival during the first postoperative year after ATAAD repair.

Sex-related differences in outcome of thoracic aortic surgery

BACKGROUND

Sex-related dissimilarities' influence on outcomes following thoracic aortic surgery is poorly understood. Our aim is to examine sex-related disparities in patients undergoing thoracic aortic aneurysm (TAA).

METHODS

A total of 455 cases undergoing thoracic aortic aneurysm (TAA) surgery were consecutively enrolled between December 2009 and December 2015 in a Chinese hospital. Primary outcomes, including overall mortality and related risk factors, were evaluated. Cox regression is utilized to recognize the independent risk factor of these consequences.

RESULTS

Females, compared to males, had greater indexed aortic diameters and higher aortic transvalvular pressure differences. For the location of aortic aneurysms, females had a higher rate of aortic arch involvement, while males had a higher rate of root involvement. Females underwent less frequent complex proximal aortic operations compared with males (29.5% versus 46.9%; p < 0.001). Women and men both had a lower rate of aortic transvalvular pressure difference and LV volume index 7 days after thoracic aortic surgery. The overall mortality for the women's groups (11%) was suggestively greater compared to 4.9% for the men's groups (p = 0.026). Renal failure and aortic arch involvement were the main risk factors associated with males' survival, while maximum indexed aortic diameter and cross-clamp time were the risk factors associated with females' survival.

CONCLUSIONS

The outcome after TAA surgery was less favorable in women with significantly increased overall mortality. It highlights the need to focus on implementing personalized surgery strategies and gender-specific guidelines in treating female patients following TAA surgery.

Transfusion of non-red blood cell blood products does not reduce survival following cardiac surgery

OBJECTIVES

The literature supports the assertion that patients undergoing cardiac surgery who receive perioperative packed red blood cell (pRBC) transfusions have increased associated mortality. The aim of the current study is to assess whether there is an association between non-pRBC blood product transfusions and increased mortality.

METHODS

Data from our center's Society of Thoracic Surgeons database included patients who underwent cardiac surgery from 2010 to 2018. Patients with pRBC transfusions or circulatory arrest were excluded. Propensity matching was performed (1:1; caliper = 0.2 times the standard deviation of logit of propensity score). Kaplan-Meier estimates and Cox regression were used. Cardiac transplant, ventricular assist devices, transcatheter aortic valves, and patients who had experienced circulatory arrest were excluded from this analysis.

RESULTS

A total of 8042 patients met criteria for analysis. Following propensity matching (1:1), 395 patients requiring perioperative non-pRBC blood products (platelets, fresh-frozen plasma, and cryoprecipitate) were matched with 395 nontransfusion patients, yielding equitable patient cohorts. Median follow-up was 4.5 (3.0-6.4) years. Patients received platelets (327 [82.8%]), fresh-frozen plasma (141 [35.7%]), and cryoprecipitate (60 [15.2%]). There was no significant difference in the postoperative mortality (6 [1.5%] vs 4 [1.0%]; P = .52). Reoperation (20 [5.0%] vs 8 [2.0%]; P < .02) and prolonged ventilation (36 [9.1%] vs 19 [4.8%]; P < .02) were greater in the transfusion group. Emergent operation (odds ratio [OR] 2.86 [1.72-4.78]; P < .001), intra-aortic balloon pump (OR 3.24 [1.64-6.39]; P < .001), and multivalve operation (OR 4.34 [2.83-6.67]; P < .001) were significantly associated with blood product use. Blood product transfusion (hazard ratio; 1.15 [0.89-1.48]; P = .3) was not significantly associated with increased mortality risk. There was no significant long-term survival difference between cohorts.

CONCLUSIONS

Patients who undergo cardiac surgery requiring blood products alone, without pRBC transfusion, have similar postoperative and long-term survival compared with patients not requiring blood products. These data are based on a limited patient sample, and future studies will aid in improving the generalizability of these results.

Elective Ascending Aortic Aneurysm Surgery in the Elderly

BACKGROUND

No clear guidelines exist for performing preventive surgery for ascending aortic (AA) aneurysm in elderly patients. This study aims to provide insights by: (1) evaluating patient and procedural characteristics and (2) comparing early outcomes and long-term mortality after surgery between elderly and non-elderly patients.

METHODS

A multicenter retrospective observational cohort-study was performed. Data was collected on patients who underwent elective AA surgery in three institutions (2006-2017). Clinical presentation, outcomes, and mortality were compared between elderly (≥70 years) and non-elderly patients.

RESULTS

In total, 724 non-elderly and 231 elderly patients were operated upon. Elderly patients had larger aortic diameters (57.0 mm (IQR 53-63) vs. 53.0 mm (IQR 49-58), p < 0.001) and more cardiovascular risk factors at the time of surgery than non-elderly patients. Elderly females had significantly larger aortic diameters than elderly males (59.5 mm (55-65) vs. 56.0 mm (51-60), p < 0.001). Short-term mortality was comparable between elderly and non-elderly patients (3.0% vs. 1.5%, p = 0.16). Five-year survival was 93.9% in non-elderly patients and 81.4% in elderly patients (p < 0.001), which are both lower than that of the age-matched general Dutch population.

CONCLUSION

This study showed that in elderly patients, a higher threshold exists to undergo surgery, especially in elderly females. Despite these differences, short-term outcomes were comparable between 'relatively healthy' elderly and non-elderly patients.

Low preoperative serum fibrinogen level is associated with postoperative acute kidney injury in patients with in acute aortic dissection

OBJECTIVE

Acute kidney injury (AKI) after cardiac surgery is associated with serious complication and high risk of mortality. The relationship between hemostatic system and the prognosis of patients with acute type A aortic dissection (ATAAD) has not been evaluated. The purpose of this study was to investigate the association between preoperative serum fibrinogen level and risk of postoperative AKI in patients with ATAAD.

METHODS

A total of 172 consecutive patients undergoing urgent aortic arch surgery for ATAAD between April 2020 and December 2021 were identified from Beijing Anzhen Hospital aortic surgery database. The primary outcome was postoperative AKI as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. The univariate and multivariate logistic regression analysis were done to assess the independent predictors of risk for postoperative AKI. Receiver operating characteristic (ROC) curve was generated to evaluate the predictive probabilities of risk factors for AKI.

RESULTS

In our study, 51.2% (88/172) patients developed postoperative AKI. Multivariate logistic regression analysis identified low preoperative serum fibrinogen level (OR, 1.492; 95% CI, 1.023 to 2.476; p = 0.021) and increased body mass index (BMI) (OR, 1.153; 95% CI, 1.003 to 1.327; p = 0.046) as independent predictors of postoperative AKI in patients with ATAAD. A mixed effect analysis of variance modeling revealed that obese patients with low preoperative serum fibrinogen level had higher incidence of postoperative AKI (p = 0.04). The ROC curve indicated that low preoperative serum fibrinogen level was a significant predictor of AKI [area under the curve (AUC), 0.771; p < 0.001].

CONCLUSIONS

Low preoperative serum fibrinogen level and obesity were associated with the risk of postoperative AKI in patients with ATAAD. These data suggested that low preoperative serum fibrinogen level was preferred marker for predicting the postoperative AKI, especially in obese patients with ATAAD.

Knowledge, attitudes, and practice preferences in the surgical threshold for ascending aortic aneurysm among Canadian cardiac surgeons

OBJECTIVE

The survey aimed to assess the practice patterns of Canadian cardiac surgeons on the size threshold at which patients with ascending aortic aneurysm would be offered surgery.

METHODS

A 18-question electronic survey was electronically distributed to 148 practicing cardiac surgeons in Canada via email from January to August 2020. Questions presented clinical scenarios focusing on modifying a single variable, and respondents were asked to identify their surgical size threshold for each of the clinical scenarios.

RESULTS

The individual response rate was 62.0% (91/148) and institutional response rate was 89.3% (25/29). For an incidental asymptomatic ascending aortic aneurysm in a 60-year-old otherwise-healthy male patient with a tricuspid aortic valve and bicuspid aortic valve of 1.9 m², 20.2% of the respondents would recommend surgery when the aneurysm was <5.5 cm. A significant number of surgeons modified their surgical threshold in response to changes to BSA, bicuspid aortic valve, growth rate, age, occupation, symptom, and family history (P < .01). Notably, if the patient had a bicuspid aortic valve, 41.0% of respondents lowered their threshold for surgery, with only 43.0% recommending surgery at ≥5.5 cm (P < .01).

CONCLUSIONS

Practice variations exist in the current size threshold for surgery of ascending aortic aneurysms in Canada. These differences between surgeons are further accentuated in the context of bicuspid aortic valve, smaller body stature, younger age, low growth rate, family history, and for the performance of isometric exercise. These represent important areas where future prospective studies are required to inform best practice.

Deep Versus Moderate Hypothermia in Acute Type A Aortic Dissection: A Propensity-Matched Analysis

BACKGROUND

The ideal temperature for hypothermic circulatory arrest (HCA) during acute type A aortic dissection (ATAAD) repair has yet to be determined. We examined the clinical impact of different degrees of hypothermia during dissection repair.

METHODS

Out of 240 cases of ATAAD between June 2014 and December 2019, 228 patients were divided into two groups according to lowest intraoperative temperature: moderate hypothermic circulatory arrest (MHCA) (20-28°C) versus deep hypothermic circulatory arrest (DHCA) (<20°C). From this, 74 pairs of propensity-matched patients were analysed with respect to operative data and short-term clinical outcomes. Independent predictors of a composite outcome of 30-day mortality and stroke were identified.

RESULTS

Mean lowest temperature was 25.5±3.9°C in the MHCA group versus 16.0±2.9°C in DHCA. Overall 30-day mortality of matched cohort was 11.5% (17 deaths), there were no significant different between matched groups. Cardiopulmonary bypass (CPB) times were longer in DHCA (221.0±69.9 vs 190.7±74.5 mins, p=0.01). Antegrade cerebral perfusion (ACP) during HCA predicted a lower composite risk of 30-day mortality and stroke (OR 0.38). Female sex (OR 4.71), lower extremity ischaemia at presentation (OR 3.07), and CPB >235 minutes (OR 2.47), all portended worse postoperative outcomes.

CONCLUSIONS

A surgical strategy of MHCA is at least as safe as DHCA during repair of acute type A aortic dissection. ACP during HCA is associated with reduced 30-day mortality and stroke, whereas female sex, lower extremity ischaemia, and longer CPB times are all predictive of poorer short-term outcomes.

Risk Factors for Postoperative Acute Kidney Injury in Patients Undergoing Redo Cardiac Surgery Using Cardiopulmonary Bypass

Objective: This paper aimed to investigate the incidence and risk factors of postoperative acute kidney injury (AKI) in adult patients undergoing redo cardiac surgery with cardiopulmonary bypass (CPB), and explore the impact of AKI on early outcomes. Methods: A total of 116 patients undergoing redo cardiac surgery with CPB between November 2017 and May 2021 were included. Patients were divided into two groups, AKI group and non-AKI group, according to the Kidney Disease Improving Global Outcomes criteria. Perioperative variables were retrospectively collected and analyzed. Risk factors for the development of AKI were investigated by univariate and multiple logistic regression models. Clinical outcomes were also compared between the groups. Results: Postoperative AKI occurred in 63 patients (54.3%), among whom renal replacement therapy was required in 12 patients (19.0%). The mechanical ventilation time (AKI: 43.00 (19.00, 72.00) hours; non-AKI: 18.00 (15.00, 20.00) hours; p < 0.001), ICU length of stay (AKI: 4.00 (2.00, 6.00) days; non-AKI: 3.00 (2.00, 4.00) days; p = 0.010), hospital length of stay since operation (AKI: 12.00 (8.00, 18.00) days; non-AKI: 9.00 (7.00, 12.50) days; p = 0.024), dialysis (AKI: 12.00 (19.05%); non-AKI: 0 (0%); p = 0.001), reintubation (AKI: 7.00 (11.11%); non-AKI: 0 (0%); p = 0.035), and hospital mortality (AKI: 8.00 (12.70%); non-AKI: 0 (0%); p = 0.020) were all higher in the AKI group than in the non-AKI group. Multivariate analysis revealed that high aspartate aminotransferase (OR, 1.028, 95% CI, 1.003 to 1.053, p = 0.025), coronary angiogram within 2 weeks before surgery (OR, 3.209, 95% CI, 1.307 to 7.878, p = 0.011) and CPB time (OR, 1.012, 95% CI, 1.005 to 1.019, p = 0.001) were independent risk factors for postoperative AKI. Conclusions: High aspartate aminotransferase, coronary angiogram within 2 weeks before surgery and CPB time seem to be associated with an increased incidence of postoperative AKI in patients with redo cardiac surgery.

Cerebral protection using deep hypothermic circulatory arrest versus retrograde cerebral perfusion for aortic hemiarch reconstruction

BACKGROUND

With evolutions in technique, recent data encourage the use of cerebral perfusion during aortic arch repair. However, a randomized data have demonstrated higher rates of neurologic injury according to MRI lesions using antegrade cerebral perfusion during hemiarch reconstruction.

METHODS

This was a retrospective review of two institutional aortic center databases to identify adult patients who underwent aortic hemiarch reconstruction for elective aortic aneurysm or acute type A aortic dissection. Patients were stratified according to cerebral protection method: (1) deep hypothermic circulatory arrest (DHCA) group versus (2) DHCA/retrograde cerebral perfusion (RCP) group.

RESULTS

A total of 320 patients and 245 patients underwent hemiarch reconstruction for aortic aneurysm electively and aortic dissection, respectively. In aneurysmal pathology, the DHCA group included 133 patients and the DHCA/RCP group included 187 patients. Operative mortality was 0.8% in the DHCA group and 2.7% in the DHCA/RCP group (p = 0.41). Kaplan-Meier survival estimates revealed comparable 2-year survival (p = 0.14). In dissection, 43 patients and 202 patients were included in the DHCA group and the DHCA/RCP group, respectively. Operative mortality was equivalent between the two groups (11.6% in the DHCA group and 9.4% in the DHCA/RCP group, p = 0.58). Long-term survival was similar at 2 years between the groups (p = 0.06). Multivariable analysis showed cerebral perfusion strategy was not associated with the composite outcome of operative mortality and stroke.

CONCLUSIONS

In treating both elective and acute ascending aortic pathologies with hemiarch reconstruction, both DHCA alone or in combination with RCP yield comparable results.

Does deeper hypothermia reduce the risk of acute kidney injury after circulatory arrest for aortic arch surgery?

OBJECTIVES

The impact of hypothermic circulatory arrest (HCA) temperature on postoperative acute kidney injury (AKI) has not been evaluated. This study examined the association between circulatory arrest temperatures and AKI in patients undergoing proximal aortic surgery with HCA.

METHODS

A total of 759 consecutive patients who underwent proximal aortic surgery (ascending ± valve ± root) including arch replacement requiring HCA between July 2005 and December 2016 were identified from a prospectively maintained institutional aortic surgery database. The primary outcome was AKI as defined by Risk, Injury, Failure, Loss, End Stage Renal Disease (ESRD) criteria. The association between minimum nasopharyngeal (NP) and bladder temperatures during HCA and postoperative AKI was assessed, adjusting for patient-level factors using multivariable logistic regression.

RESULTS

A total of 85% (n = 645) of patients underwent deep hypothermia (14.1-20.0°C), 11% (n = 83) low-moderate hypothermia (20.1-24.0°C) and 4% (n = 31) high-moderate hypothermia (24.1-28.0°C) as classified by NP temperature. When analysed by bladder temperature, 59% (n = 447) underwent deep hypothermia, 22% (n = 170) low-moderate, 16% (n = 118) high-moderate and 3% mild (n = 24) (28.1-34.0°C) hypothermia. The median systemic circulatory arrest time was 17 min. The incidence of AKI did not differ between hypothermia groups, whether analysed using minimum NP or bladder temperature. In the multivariable analysis, the association between degree of hypothermia and AKI remained non-significant whether analysed as a categorical variable (hypothermia group) or as a continuous variable (minimum NP or bladder temperature) (all P > 0.05).

CONCLUSIONS

In patients undergoing proximal aortic surgery including arch replacement requiring HCA, degree of systemic hypothermia was not associated with the risk of AKI. These data suggest that moderate hypothermia does not confer increased risk of AKI for patients requiring circulatory arrest, although additional prospective data are needed.

Long-term outcomes of hemiarch replacement with hypothermic circulatory arrest and retrograde cerebral perfusion

OBJECTIVE

This study sought to report outcomes of hemiarch replacement with hypothermic circulatory arrest and retrograde cerebral perfusion, and secondarily, to report outcomes of this operative approach by type of underlying aortic disease.

METHODS

This was an observational study of aortic surgeries from 2010 to 2018. All patients who underwent hemiarch replacement with retrograde cerebral perfusion were included, whereas patients undergoing partial or total arch replacement or concomitant elephant trunk procedures were excluded. Patients were dichotomized into 2 groups by underlying aortic disease; that is, acute aortic dissection (AAD) or aneurysmal degeneration of the aorta. These groups were analyzed for differences in short-term postoperative outcomes, including stroke and operative mortality (Society of Thoracic Surgeons definition). Multivariable Cox analysis was performed to identify variables associated with long-term survival after hemiarch replacement.

RESULTS

A total of 500 patients undergoing hemiarch replacement with hypothermic circulatory arrest plus retrograde cerebral perfusion were identified, of whom 53.0% had aneurysmal disease and 47.0% had AAD. For the entire cohort, operative mortality was 6.4%, whereas stroke occurred in 4.6% of patients. Comparing AAD with aneurysm, operative mortality and stroke rates were similar across each group. Five-year survival was 84.4% ± 0.02% for the entire hemiarch cohort, whereas 5-year survival was 88.0% ± 0.02% for the aneurysm subgroup and was 80.5% ± 0.03% for the AAD subgroup. On multivariable analysis, AAD was not associated with an increased hazard of death, compared with aneurysm (P = .790).

CONCLUSIONS

Morbidity and mortality after hemiarch replacement with hypothermic circulatory arrest plus retrograde cerebral perfusion are acceptably low, and this operative approach may be as advantageous for AAD as it is for aneurysm.

Moderate Versus Deep Hypothermia in Type A Acute Aortic Dissection Repair: Insights from the International Registry of Acute Aortic Dissection

BACKGROUND

The optimal strategy for cerebral protection during repair of type A acute aortic dissection has yet to be determined. We sought to determine the impact of differing degrees of hypothermia in patients undergoing acute dissection repair.

METHODS

All patients in the International Registry of Acute Aortic Dissection Interventional Cohort database who underwent type A acute aortic dissection repair between 2010 and 2018 were identified. Data for operative temperature were available for 1962 patients subsequently divided into 2 groups according to lowest temperature: moderate hypothermic circulatory arrest (MHCA) (20-28°C) versus deep hypothermic circulatory arrest (DHCA) (<20°C). We then propensity matched 362 pairs of patients and analyzed operative data and short-term outcomes.

RESULTS

The median lowest temperature was 25.0°C in the matched MHCA group as compared with 18.0°C in the DHCA group. For the entire cohort of 1962 patients, in-hospital mortality was 14.2% (278 deaths) but was not significantly different between DHCA and MHCA. The perioperative stroke rate was comparable between groups, before and after propensity matching. Circulatory arrest times were significantly longer in the MHCA cohort, regardless of matching. Use of antegrade or retrograde cerebral perfusion was similar in matched groups. There were no differences in 30-day survival or in other major postoperative morbidity between the 2 matched cohorts.

CONCLUSIONS

A surgical strategy of MHCA + antegrade cerebral perfusion is at least as safe as DHCA during repair of acute type A aortic dissection.

Time of day does not influence outcomes in acute type A aortic dissection: Results from the IRAD

BACKGROUND

Type A acute aortic dissection (TAAAD) represents a surgical emergency requiring intervention regardless of time of day. Whether such a "evening effect" exists regarding outcomes for TAAAD has not been previously studied using a large registry data.

METHODS

Patients with TAAAD were identified from the International Registry of Acute Aortic Dissections (1996-2019). Outcomes were compared between patients undergoing operative repair during the daytime (D), defined as 8 am-5 pm, versus the evening (N), defined as 5 pm-8 am.

RESULTS

Four thousand one-hundrd and ninety-seven surgically treated patients with TAAAD were identified, with 1824 patients undergoing daytime surgery (43.5%) and 2373 patients undergoing evening surgery (56.5%). Daytime patients were more likely to have undergone prior cardiac surgery (13.2% vs. 9.5%; p < .001) and have had a prior aortic dissection (4.8% vs. 3.4%; p = .04). Evening patients were more likely to have been transferred from a referring hospital (70.8% vs. 75.0%; p = .003). Daytime patients were more likely to undergo aortic valve sparing root procedures (23.3% vs. 19.2%; p = .035); however, total arch replacement was performed with equal frequency (19.4% vs. 18.8%; p = .751). In-hospital mortality (D: 17.3% vs. N. 16.2%; p = .325) was similar between both groups. Subgroup analysis examining the effect of weekend presentation revealed no significant mortality difference.

CONCLUSIONS

A majority of TAAAD patients underwent surgical repair at night. There were higher rates of postoperative tamponade in evening patients; however, mortality was similar. The expertise of cardiac-dedicated operative and critical care teams regardless of time of day as well as training paradigms may explain similar mortality outcomes in this high risk population.

Early Onset of Postoperative Gastrointestinal Dysfunction Is Associated With Unfavorable Outcome in Cardiac Surgery: A Prospective Observational Study

Objective:

The distribution of postoperative gastrointestinal (GI) dysfunction and its association with outcome were investigated in cardiac surgery patients. Gastrointestinal function was evaluated using the Acute Gastrointestinal Injury (AGI) grade proposed by the European Society of Intensive Care Medicine.

Design:

Prospective observational study at a single center.

Setting:

University hospital.

Patients:

Consecutive patients presenting for elective cardiac surgery with extracorporeal circulation (ECC).

Interventions:

None.

Results:

Daily assessment using the AGI grade was performed on the first 3 postoperative days in addition to standard care. For analysis, 3 groups were formed based on the maximum AGI grade: AGI 0, AGI 1, and AGI ≥2. Five hundred and one patients completed the study; 32.7%, 65.1%, and 2.2% of the patients scored a maximum AGI 0, AGI 1, and AGI ≥2, respectively. Patients with AGI grade ≥2 had more frequently undergone thoracic aortic surgery and had longer surgery duration and time on ECC. Patients with AGI grade ≥2 had statistically significant higher frequency of GI complications within 30 days (63.6% vs 1.2% and 5.5% in patients with AGI 0 and AGI 1) and higher 30-day mortality (9.1% vs 0.0% and 1.8% in patients with AGI 0 and AGI 1).

Conclusions:

Early GI dysfunction following cardiac surgery was associated with an unfavorable outcome. Increased attention to GI dysfunction in cardiac surgery patients is warranted and the AGI grade could be a helpful adjunct to a structured approach.

The impact of centre volume on outcomes of orthotopic heart transplant in older recipients

OBJECTIVES

The aim of this study was to evaluate the impact of overall and older-recipient-specific centre volumes on outcomes of orthotopic heart transplant (OHT) in older recipients.

METHODS

Patients aged ≥60 years undergoing OHT were identified in the United Network for Organ Sharing (UNOS) registry. The primary outcome was 1-year post-OHT mortality. Secondary outcomes included the incidence and impact on 1-year survival of postoperative complications including infection, renal failure requiring dialysis and stroke. Patients were divided into equal size tertiles based on overall and older-recipient-specific OHT centre volumes.

RESULTS

A total of 5373 older recipients were identified. Mean overall and older-recipient-specific volumes were 27.5 ± 19.5 and 9.4 ± 7.3 OHT/year, respectively. Although overall and older-recipient-specific low-volume centres were at higher risk of mortality in separate multivariable analysis, only older-recipient-specific volume contributed significantly to post-OHT mortality in the combined multivariable analysis (P < 0.05). In the receiver operating characteristic analysis, an older-recipient-specific volume of 8 OHTs/year was identified as the most discriminative volume threshold for mortality (area under the receiver operating characteristic curve = 0.68). Although low older-recipient-specific volume centres did not have significantly higher incidences of postoperative complications, they had significantly worse 1-year survival rates compared to higher volume centres in patients with postoperative infection or dialysis (each P < 0.01).

CONCLUSIONS

This large-cohort analysis demonstrates that older-recipient-specific centre volume contributes to post-OHT outcomes in the older recipients more significantly than overall volume. This may be a consequence of higher older-recipient-specific volume centres to better manage specific complications in this patient population.

Shared Decision-Making in Acute Surgical Illness: The Surgeon's Perspective

BACKGROUND

Surgical patients increasingly have more comorbidities and are of an older age, complicating surgical decision-making in emergent situations. Little is known about surgeons' perceptions of shared decision-making in these settings.

STUDY DESIGN

Twenty semi-structured interviews were conducted with practicing surgeons at 2 large academic medical centers. Thirteen questions and 2 case vignettes were used to assess perceptions of decision-making, considerations when deciding whether to offer to operate, and communication patterns with patients and families.

RESULTS

Thematic analysis revealed 6 major themes: responsibility for the decision to operate, perceived futility, surgeon judgment, surgeon introspection, pressure to operate, and costs of the operation. Perceived futility was universally considered a contraindication to surgical intervention. However, the challenge of defining futility led participants to emphasize the importance of patients' self-determined risk-to-benefit analysis when considering surgical intervention. More experienced surgeons reported greater comfort with communicating to patients that a condition was not amenable to an operation and reserved the right to refuse to operate.

CONCLUSIONS

Due to external pressures and uncertainty, some providers err on the side of operative intervention, despite suspected futility. Greater experience allows surgeons to withstand external pressures, be confident in their assessments of perceived futility, and guide patients and their families away from additional interventions.