Cardiovascular diseases remain the leading cause of death worldwide, accounting for approximately 17.9 million deaths annually, with atherosclerosis as the predominant underlying pathology [1][2]. Aortic pathologies, particularly ascending aortic aneurysms and acute type A aortic dissections, represent a critical subset with exceptionally high mortality if left untreated—up to 1% - 2% per hour in the first 48 hours for acute dissections [3][4].

Over the past three decades, substantial improvements in diagnostic imaging—transesophageal echocardiography (TEE), computed tomography angiography (CTA), and magnetic resonance imaging (MRI)—have enabled earlier and more accurate identification of aortic disease, even in emergency settings [5][6]. These modalities have not only improved diagnostic accuracy but have also profoundly influenced therapeutic decision-making, shifting management toward timely surgical intervention [7].

Atherosclerosis plays a central role in the pathogenesis of non-genetic aortic aneurysms and dissections by promoting chronic inflammation, medial degeneration, elastin fragmentation, and intimal disruption [8][9]. The disease process involves endothelial dysfunction, oxidized low-density lipoprotein (ox-LDL) accumulation, monocyte/macrophage infiltration, foam cell formation, and cytokine-driven fibrous cap thinning, ultimately leading to plaque rupture or intramural hematoma propagation [10]-[12]. In the ascending aorta, these mechanisms are exacerbated by high shear stress and pulsatile flow, contributing to aneurysmal dilation or acute dissection [13].

Surgical repair remains the cornerstone of treatment. Elective procedures for aneurysmal disease allow preoperative optimization, resulting in lower perioperative risk [14]. In contrast, emergency repair of acute type A dissection is frequently performed in hemodynamically unstable patients with multi-organ compromise, prolonged operative times, and systemic inflammatory activation triggered by cardiopulmonary bypass (CPB) and hypothermic circulatory arrest (HCA) [15]-[17].

Recent international registries (IRAD, German Registry for Acute Aortic Dissection Type A [GERAADA]) consistently report in-hospital mortality of 18% - 26% for emergency type A repairs, compared to <5% for elective ascending aortic surgery [18]-[20]. Despite global advancements, regional data from Southeast Europe, including Bosnia and Herzegovina, remain limited. Single-center experiences frequently reveal higher complication rates due to delayed presentation, limited access to hybrid operating rooms, and differences in preoperative stabilization protocols [21]. The present study therefore aimed to compare intraoperative parameters and postoperative outcomes between elective and emergency ascending aortic reconstructions in a Balkan cohort, with particular emphasis on the impact of procedural urgency, CPB/HCA duration, and organ-specific complications.

Emergency ascending aortic repair was associated with significantly longer operative times, higher rates of organ-specific complications, and markedly increased in-hospital mortality compared with elective repair. These univariate associations are consistent with large international registries (IRAD and GERAADA) reporting mortality of 18% - 27% for acute type A dissection [18][19]. A major limitation is the substantial baseline imbalance between groups. Emergency patients had markedly higher rates of preoperative shock (82% vs. 0%) and renal insufficiency (42% vs. 6%). These factors are well-established, strong confounders and likely account for a significant portion of the observed differences in postoperative cardiac failure, renal dysfunction, and mortality. Therefore, the reported associations should be interpreted as univariate findings rather than independent effects of procedural urgency. Multivariable adjustment or propensity-score matching would be required in future studies to better isolate the contribution of emergency status. All causal language in this manuscript has been tempered accordingly. Prolonged CPB (>180 min) and HCA (>30 min) were associated with increased morbidity in univariate analysis. These thresholds were pre-specified based on prior literature demonstrating elevated renal injury risk beyond 180 min of CPB and visceral ischemia risk beyond 30 min of HCA [22][23]. The findings reinforce the clinical importance of minimizing operative durations and optimizing organ-protection strategies in acute aortic syndromes.

The strikingly higher incidence of cardiac complications (70% vs. 18%) in emergency cases likely reflects the combined effects of preoperative shock, coronary malperfusion in type A dissection, prolonged myocardial ischemia during ACC, and post-CPB myocardial stunning [19]. Renal dysfunction (48% vs. 16%) mirrors findings from multiple studies showing acute kidney injury rates of 30% - 50% after emergency aortic surgery, driven by hypoperfusion, inflammatory mediators, and hemoglobinuria [24][25]. Respiratory complications were also more frequent in emergencies, consistent with reports linking prolonged CPB to acute lung injury via neutrophil activation and cytokine storm [21]. Preoperative shock (82% in emergency group) emerged as the strongest predictor of mortality (present in 86.7% of fatal cases), corroborating previous observations that hemodynamic instability at presentation is the dominant determinant of survival in acute type A dissection [15][26]. The high rate of redo procedures in the emergency group (38%) further increased operative complexity and bleeding risk, a finding consistent with literature showing reoperation as an independent mortality predictor [27]. These results highlight the importance of regional system improvements, including prehospital transfer protocols, rapid imaging-to-surgery pathways, and multidisciplinary aortic teams, which have been shown to reduce mortality by 30% - 50% in high-volume centers [22][28]. Future efforts should focus on neuroprotective and organ-protective adjuncts (e.g., selective antegrade cerebral perfusion, pulsatile perfusion, pharmacologic preconditioning) and hybrid techniques for high-risk patients [29]. Limitations of this study include its single-center design, relatively modest sample size, and lack of long-term follow-up. Nonetheless, the detailed intraoperative and complication data provide valuable regional insights and reinforce the global consensus that procedural urgency remains a major determinant of outcome in ascending aortic surgery.

Emergency ascending aortic surgery is associated with significantly prolonged operative times, higher rates of major organ complications, and markedly increased in-hospital mortality compared to elective repair. Strategies aimed at minimizing CPB and HCA durations, aggressive preoperative stabilization, and implementation of advanced organ-protection techniques are essential to bridge the outcome disparity between elective and acute presentations.

Conceptualization: M.T., R.S., M.T.; methodology: M.T.; formal analysis: M.T., R.S.; writing—original draft: M.T., R.S., M.T.; writing—review & editing: M.T., R.S., M.T.