IT IS A POTENTIALLY LIFE-THREATENING COMPLICATION THAT COULD OCCUR AFTER ANY INVASIVE PROCEDURE
Arterial pseudoaneurysm is a clinical condition in which the wall of a blood vessel collapses due to some arterial injury, and the resulting leaked blood is engulfed by soft tissue, forming a cavity that is in communication with the vessel[1]. Due to the walls of the cavity are fragile and break down easily, it could cause massive haemorrhage. So, it is a potentially life-threatening complication that could occurs after any invasive procedure[2]. The study by Kakinuma et al[1], subject of this article, shows that despite evidence that the most commonly reported cause in obstetrics and gynecology patients is pregnancy related, non-pregnancy related pseudoaneurysm is not uncommon. In fact, uterine artery pseudoaneurysms are diagnosed between 0.3%[3,4] to 1%[2] out of some invasive gynecological procedures, and it has been reported that it can occur in 0.2%-0.3% of all pregnancies[1], although sometimes they are not detected on initial examinations[5], and therefore its incidence could be greater.
The pathogenesis is not fully understood, and involves any trauma, surgery, or infection that could cause vascular injury, including enzymatic degradation of the adjacent arterial wall[6]. Common examples of iatrogenic pseudoaneurysm occur, in addition to the abdominal cavity, in the neck or over the femoral vessels, due to percutaneously inserted catheters[7]. Common examples of iatrogenic traumas into the abdomen could occur during blind introduction of laparoscopic trocars[8], or other laparoscopic devices[9], and is also possible during an endoscopy, as in the study by Kakinuma et al[1].
After the vascular damage which forms the pseudoaneurysm, an increase in intra-abdominal pressure seems necessary to facilitate its rupture and concomitant bleeding[10]. Since there were no images of pseudoaneurysms prior to hysteroscopy in the reported patient[1], it can be deduced that the arterial injury could have been caused by the blind introduction of the hysteroscopic device, and the increase in intra-abdominal pressure could have been caused by an high-pressure intrauterine perfusion system. In general, the wide spectrum of symptoms associated with a pseudoaneurysm mimicking other conditions makes it a chameleon pathology[10]. Thus, despite its clinical debut it would be necessary to establish the magnitude of the problem through physical examination, serial analytical tests, and a rigorous clinical follow-up of the evolution to monitor disease progression and treatment effectiveness to exclude the presence of bleeding[2].
When suspected, color Doppler ultrasonography is indicated, but also suffers from limitations in detecting the vessel supplying the pseudoaneurysm, whose identification directly affects the treatment planning[10]. In the Kakinuma et al’s report[1], transvaginal ultrasound after hysteroscopic polypectomy was the technique that facilitated the suspected diagnosis. The etiological diagnosis is usually confirmed by computed tomography angiography[1], or magnetic resonance imaging[3]. In Japan, health services are universal, and this advantageous situation makes it easier for citizens to access to them, which significantly facilitates diagnosis and treatment[11]. In the Kakinuma et al’s report[1], the patient had to be transferred from a general hospital to a reference hospital, equipped with appropriate technical and human resources, and where various advanced endovascular procedures managed by specialized personnel were applied to successfully resolve the emerging situation.
PREDICT THE RISK OF HAEMORRHAGE
The prognosis of this entity depends on the cause that causes it, although its mortality is mainly derived from its complications specially by bleeding due to its rupture[1] or the vascular insufficiency that it causes in the affected organ[7,12]. Some pseudoaneurysms are known to resolve spontaneously, while others rupture and cause massive bleeding. Small pseudoaneurysms have been reported to clot spontaneously, so another approach that could be used includes the “watch-and-wait” strategy, with rigorous monitoring and follow-up, at least initially[4]. In asymptomatic patients, follow-up and repetition of imaging tests, such as magnetic resonance imaging, angiography, computed tomography, or diagnostic laparoscopy, may be recommended in selected cases[2]. But the majority are diagnosed with some acute complication, so the conservative attitude is less common.
Remarkably, in an asymptomatic patient, it is difficult to predict the risk of haemorrhage, which depends on various circumstances, such as: (1) The size and location of the ruptured artery which are the first determining factors[2,10]. This anatomical factor could also decide the management, taking into account that endovascular approach would be technically simpler than the conventional laparoscopic approach[3], especially if complex and deep anatomical areas are involved[6]; (2) The progressive changes in the size of lesions by imaging techniques could rule out a conservative attitude[4]; (3) A crucial limiting factor is the availability of sufficient and appropriate therapeutic resources of the medical center where the patient is admitted, including the feasibility of endovascular radiologists or magnetic resonance imaging[1]; (4) In addition, the therapeutic strategy could be modified depending on the type of patient´s residence: Rural or urban, transportation means, communication routes and distances to their hospital. It is intuitive that patients who can present with life-threatening problems may have better outcomes if treated as quickly as possible[13]; (5) It is considered that mortality due to pseudoaneurysm rupture is greater than mortality due to surgical intervention, where open surgical procedures have excellent patency rates but at the cost of substantial morbidity[14]. On the other hand, endovascular treatment has good safety and short-term efficacy with decreased morbidity, complications, and costs compared with open surgical procedures[5]; (6) The anesthetic risk is lower in the endovascular approach than in the conventional approach, a decisive therapeutic indication for patients with high surgical risk or who have concomitant diseases. Therefore, endovascular repair is a less invasive surgical approach for the treatment of critically ill patients[15], or even, prophylactic embolization of pseudoaneurysms detected early in the postoperative period can also prevent late hemorrhage[16]; (7) Ageing could be a factor associated with a higher risk of complications[17,18], due to the fact that chronic diseases are more common with increasing age[19], and sometimes this factor can decide the therapeutic attitude in those patients; and (8) The cost of endovascular procedures or surgical intervention could be a limiting factor, depending on the implants selected and the size of the artery to be repaired. In Japan, health services are mostly universal[11]. Thus, in the report of Kakinuma et al[1], there was no problem evacuating the patient to a hospital with appropriate radiological means and interventional radiologists, who successfully resolved the emerging situation.
In summary, endovascular treatment is safe and effective in the short-term, with lower morbidity, complications, and costs, compared to open surgical procedures which have excellent long-term effectiveness but higher morbidity[14,20]. Thus, some authors have stated that at least initially, regardless of the associated symptoms or diameter, the pseudoaneurysm should be treated mainly through endovascular procedures[5,6]. Therefore, it seems that endovascular treatment could be considered the standard of care for abdominal pseudoaneurysms in general and for uterine pseudoaneurysms in particular[6], although further studies are required to determine its long-term durability[14].
Finally, the authors want to expressly highlight the limitations of the statement stated in the previous paragraph, and in the conclusion section, reminding readers that the limitations of the article have been exposed throughout the manuscript, and are summarized in: (1) The absence of significant publications of clinical cases series in the bibliography, being a rare entity, from which the spirit of the authors emanates when deciding to write this article; (2) The great heterogeneity of the affected patients makes difficult to obtain a homogeneous sample for any study; (3) The vague symptoms that can present until triggering the threat of massive hemorrhage, which makes its diagnosis difficult and causes its delay, with potential consequences on its prognosis; (4) Its debut more frequently as a clinical emergency, which makes it difficult to obtain cases for the sample, at even a national level; (5) The different existing therapeutic techniques that are mentioned in the text; (6) The different factors analyzed throughout the manuscript that influence the diagnosis and treatment, such as the patient’s national health system, or others mentioned; and (7) The absence of scientific evidence that accurately demonstrates the clinical sequence to follow, both in diagnosis and treatment. Therefore, it seems evident that it will be very difficult to design future studies on this entity.
