Iatrogenic aortic dissection (iAD) is an uncommon but potentially serious complication that may occur during cardiac interventions and percutaneous procedures. As cardiac surgeons, it is important to distinguish it from spontaneous acute aortic dissection (sAD) and to understand its clinical presentation, therapeutic strategy, and expected outcomes, as it forms part of the complications derived from our own clinical activity.
The aim of this recent study by Harris et al., based on data from the International Registry of Acute Aortic Dissection (IRAD), was to compare iAD with sAD and to explore differences according to iatrogenic etiology, namely cardiac surgery or catheter-based procedures.
IRAD prospectively and retrospectively collects data from patients diagnosed with acute aortic dissection or intramural hematoma between 1996 and 2023. Cases were classified as sAD or iAD, the latter being defined as a consequence of cardiac surgical procedures, coronary catheterization, percutaneous interventions, or other invasive procedures involving the aorta.
Among the total cohort (n=13455), 333 patients (2.5%) had iAD (252 type A and 81 type B). Demographic characteristics, comorbidities, clinical presentation, imaging findings, treatment strategies, and mortality were compared. The most frequent cause of type A iAD was cardiac surgery (51%), followed by catheter-based procedures (41%). The opposite pattern was observed in type B iAD, in which catheter-related procedures were the most frequent cause (47%), followed by cardiac surgery (32%). Patients with iAD were significantly older than those with sAD and had a greater burden of comorbidities, particularly atherosclerosis, known aortic aneurysm, valve disease, diabetes, and peripheral arterial disease. The proportion of women was higher in the iAD group, especially in type A dissection.
From a clinical standpoint, iAD was characterized by an atypical presentation. Up to 30% of patients with iAD had no pain, and when pain was present, it was less abrupt, severe, or radiating than in sAD. Neurologic symptoms were also less frequent. Accordingly, computed tomography was used less often as the initial diagnostic test, whereas intraoperative diagnosis or aortography was more common.
On imaging, patients with iAD had significantly smaller aortic diameters in all assessed segments and a lower prevalence of aortic regurgitation and pericardial effusion, particularly in type A dissection. The extent of dissection was more limited, with a higher proportion of cases confined to the ascending aorta or aortic arch.
Regarding treatment, most type A dissections were surgically managed in both groups. However, medical management was more frequent in iAD than in sAD (13% vs. 8%; p = .016). This conservative approach was mainly observed in catheter-related iAD and in older patients or those with comorbidities. Time from diagnosis to intervention was longer in iAD. In type B dissection, treatment strategies were similar between iAD and sAD, although endovascular techniques were used less frequently in iAD.
Overall hospital mortality was higher in type A iAD than in spontaneous type A dissection (25.8% vs. 18.4%; p = .005). No significant differences in mortality were observed between the causes of type B dissection. Among medically managed patients with type A dissection, mortality was lower in iAD than in sAD, whereas among surgically treated patients, mortality was higher in iAD. However, after multivariable adjustment, iAD was not independently associated with higher hospital mortality in type A dissection. Survival analysis showed lower 4-year survival in patients with type A iAD compared with type A sAD (74.9% vs. 85.8%; p = .003), a difference that was attenuated after adjustment for age, although an unfavorable trend persisted.
In summary, iatrogenic aortic dissection is uncommon, affects older patients, and is associated with a higher burden of comorbidities. It usually presents with atypical symptoms and smaller aortic diameters. Management, particularly in type A dissection, is more heterogeneous and more frequently includes medical treatment. Although crude mortality is higher in type A iAD, this difference does not persist after adjustment for confounding factors, although mid-term survival remains lower.
COMMENTARY:
Iatrogenic aortic dissection is an uncommon entity but one of major clinical relevance in our daily practice as cardiac surgeons. This IRAD-based study provides a broad and detailed analysis, and its main strength lies in the large sample size and in the possibility of identifying clinically relevant differences between iAD and sAD, as well as exploring subgroups according to iatrogenic etiology.
The clearly different patient profiles between both types of dissection are particularly relevant. iAD occurs in older patients, with established atherosclerosis and previous cardiovascular disease, a profile that reflects both the indication for the procedures that trigger the event and the greater vulnerability of the aortic wall. The higher proportion of women, together with smaller aortic diameters, suggests that anatomic and vessel-size factors may influence susceptibility to iatrogenic injury, an aspect that deserves more detailed evaluation in future studies.
From a clinical perspective, the atypical presentation of iAD has direct implications for daily practice. The absence of pain or the presence of nonspecific symptoms, often in the setting of sedation, anesthesia, or the immediate postoperative period, favors diagnostic delay. This is reflected in the longer time to intervention and in the lower use of computed tomography as the initial diagnostic test. For cardiac surgeons and interventional cardiologists, these findings underline the need to maintain a high index of suspicion in the presence of any hemodynamic deterioration, myocardial ischemia, or unexpected echocardiographic finding after invasive procedures.
The study also provides relevant information on the anatomic extent of iAD, in which dissection tends to be more limited and is associated with less aortic regurgitation and a lower incidence of tamponade, factors that probably influence therapeutic decision-making. This anatomic pattern may explain, at least in part, why a subgroup of patients with type A iAD, particularly catheter-related cases, can be managed conservatively with acceptable outcomes, something that would be unthinkable in most cases of type A sAD.
The higher mortality observed in type A iAD deserves specific reflection, particularly when it occurs as a consequence of cardiac surgery. These patients accumulate several risk factors: severe underlying disease, previous complex surgery, the need for alternative cannulation, and greater challenges in cerebral and myocardial protection. Although multivariable analysis attenuates the mortality difference, the clinical impact is evident and requires extreme attention to preventive measures in every procedure, as well as individualized surgical decision-making.
This study highlights the lack of clear and specific guidelines for the management of iAD. Current recommendations are largely based on those for sAD, despite the fact that iAD has its own characteristics in terms of etiology, extent, and clinical context. The more frequent use of medical treatment in iAD reflects this uncertainty and the need for a more personalized approach.
Another important aspect is mid-term outcome. The lower 4-year survival in type A iAD suggests that the impact of iAD is not limited to the acute event, but may also influence long-term prognosis, probably in relation to the patients’ comorbidity burden and the sequelae of the initial event. This finding reinforces the importance of close follow-up and strict control of risk factors in these patients.
Among the study limitations, inherent to a registry design, are the lack of technical details regarding the procedures that caused the iAD, variability in therapeutic decision-making, and possible underestimation of mild or missed cases that were not diagnosed. In addition, the long time span of the registry, although adjusted for in the analysis, introduces changes in clinical practice that may have influenced the results.
In conclusion, this study provides an updated view of iAD, emphasizing that it is a distinct entity from sAD, with its own clinical profile and specific diagnostic and therapeutic challenges. For the cardiac surgeon, these data reinforce the need for prevention, early recognition, and individualized decision-making. As the number of transcatheter and endovascular procedures increases, further evidence will be essential to define more standardized management strategies and improve outcomes in these patients.
REFERENCE:
Harris KM, Parikh NB, Nienaber CA, Woznicki EM, Evangelista A, Schermerhorn M, et al. Iatrogenic aortic dissection: Insights from the International Registry of Acute Aortic Dissection. J Thorac Cardiovasc Surg. 2025 Dec;170(6):1503-1510.e5. doi: 10.1016/j.jtcvs.2025.05.011.
