A Patient With a Left Ventricular Assist Device Requiring Emergency Surgery for a Strangulated Umbilical Hernia: A Case Report

Introduction

The European Hernia Society classifies umbilical hernias as midline abdominal wall hernias located within the M3 zone of the abdomen (from 3 cm above to 3 cm below the umbilicus) [1]. Studies providing coherent, worldwide applicable data on incidence and complication rates of umbilical hernias are scarce, and providing reliable statistics requires referencing studies such as one conducted by Kokotovic et al, wherein 61.6% of 789 adult patients with an umbilical or epigastric hernia required surgical intervention within 5 years, 1.4% of which were acute [2]. Strangulation of an umbilical hernia is defined as compromised blood flow to the contents of the hernia (usually omentum or small bowel) [3], leading to necrosis if left untreated. Tissue necrosis can lead to bowel perforation, peritonitis, and sepsis.

It was recently estimated that patients with advanced heart failure comprise approximately 1% to 10% of the overall heart failure population [4]. The standard treatment for advanced heart failure is heart transplantation, but this has substantial limitations, primarily the significant shortage of donor organs. Mechanical circulatory support (MCS), mainly via left ventricular assist devices (LVADs), has become an alternative form of treatment for patients with advanced heart failure [4].

Our patient was implanted with a HeartWare HVAD System (HW, Medtronic, Minneapolis, MN, USA) device. The HW is a continuous-flow device, which consists of a few key components. The inflow cannula directs blood from the left ventricular cavity to the blood pump. The pump contains a centrifugal rotating impeller connected to the ascending aorta via an outflow graft. The driveline is a cable subcutaneously tunneled from the pump exiting the body at the lower abdominal wall to the external controller and the energy supply [4]. The pump assists the left ventricle in pumping blood to the aorta, thus improving the survival rate of patients with advanced heart failure and can serve either as a bridge to transplantation or as a destination therapy [5]. Implantation of the LVAD requires an individualized anticoagulation and antiplatelet regimen due to the increased risk of thromboembolic events [6].

Between 2013 and 2022, isolated continuous-flow LVADs were implanted in 27 493 patients in the United States alone [7]. In recent years, few studies have attempted to estimate the number of LVAD patients who required emergency abdominal surgery. A study by Sanaiha et al used the 2005–2015 National In-patient Sample to identify all adult LVAD patients in the United States who had required emergency general surgery (EGS). Interestingly, the annual incidence of EGS in LVAD patients decreased from 5.4% to 3.3% within this time period. Nevertheless, LVAD-EGS patients had significantly higher odds of mortality compared with non-EGS patients, with an adjusted odds ratio of 2.5 [8]. To the best of our knowledge, no comparative data regarding the incidence of emergency abdominal surgeries in LVAD patients in other parts of the world besides the United States have been published. International registry analyses, such as those from the International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support (IMACS) Registry, describe geographic differences in LVAD recipients characteristics and focused mainly on device-specific complications [9]. Consequently, the actual worldwide scale of the problem is unknown. Furthermore, no applicable guidelines for perioperative management of LVAD patients in an emergency setting have been prepared thus far and the available data are mainly anecdotal. Lack of proper preparation of the patient in terms of anticoagulation and antibiotic treatment lowers the survival chances drastically. Thus, preoperative communication with the appropriate LVAD center is advised to reduce the risk of perioperative complications [4].

This report describes the case of a 43-year-old man with an implantable cardioverter defibrillator (ICD) and a left ventricular assist device (LVAD) on long-term anticoagulation with warfarin and clopidogrel who required emergency abdominal surgery for an irreducible, strangulated umbilical hernia and a right-sided, non-strangulated inguinal hernia.

Case Report

In 2014, a 43-year-old man presented to the General, Oncological, and Endocrine Surgery Clinic of the Provincial Hospital in Kielce, Poland with a 2-day history of abdominal pain and vomiting. He had undergone an ICD implantation over 3 years prior as a sudden cardiac arrest primary preventive measure and HeartWare LVAD implantation in the Silesian Center for Heart Diseases in Zabrze, Poland 9 months prior to admission due to advanced heart failure – New York Heart Association (NYHA) class III/IV – caused by dilated cardiomyopathy. He had a medical history of hypertension, hypothyroidism, infection of the driveline exit site treated with cloxacillin, an inguinal hernia, and an umbilical hernia that was scheduled to be treated surgically 7 days after admission to our hospital. He had been receiving clopidogrel, warfarin, losartan, carvedilol, eplerenone, levothyroxine, and cloxacillin.

Upon physical examination, the abdomen was soft with generalized tenderness and normal bowel sounds. He also had an irreducible umbilical hernia (8 cm in diameter) and periumbilical erythema. Further inspection revealed a right-sided inguinal hernia. Localized pain was present upon attempting to reduce the inguinal hernia.

The initial laboratory diagnostic workup results are presented in Table 1. The hemoglobin (HGB) concentration was 11.2 g/dl (reference range: 13.0–17.2 g/dl), hematocrit (HCT) was 34.1% (reference range: 37–49.5%), prothrombin time (PT) was 24.8 s (reference range: 9.7–14.5 s), prothrombin index (PI) was 47% (reference range: 70–130%), international normalized ratio (INR) was 2.0 (reference range: 0.8–1.2), activated partial thromboplastin time (APTT) was 47.8 s (reference range: 26.0–40.0 s), and serum glucose concentration was 105 mg/dl (reference range: 65–100 mg/dl). Radiography of the chest and the abdomen were conducted. Lack of intestinal obstruction signs notwithstanding (Figure 1), his symptoms continued to worsen, requiring urgent surgery.

Because this case was managed as an emergency during the night, the feasibility of guideline-driven, elective anticoagulation strategies was significantly limited. The decision to operate was preceded by a consult with the on-call cardiology consultant from the reference center where the LVAD implantation had taken place. In accordance with the provided advice, 2 units of fresh frozen plasma (FFP) and 3 units of packed red blood cell concentrate (pRBC) were administered to maintain the INR within the range 1.5 to 2.5, which was required for proper functioning of the LVAD. Moreover, all the other perioperative decisions were taken in consonance with the LVAD implantation center and were continuously reevaluated, considering the dynamic balance between the risk of pump thrombosis and bleeding.

Prior to surgery, an INR range of 1.5 to 2.5 was intentionally maintained in lieu of complete anticoagulation reversal. This decision was dictated by the need to reduce the risk of bleeding to an acceptable level, concomitantly considering the increased risk of pump thrombosis in this dehydrated patient on continuous-flow support with imminent intestinal ischemia.

Prothrombin complex concentrate (PCC) is generally preferred over fresh frozen plasma (FFP) due to its more predictable factor profile, faster INR correction, and lower infusion volume. These advantages notwithstanding, PCC was unavailable at our hospital during nighttime emergency hours, whereas FFP was readily accessible. Because he was dehydrated, fluid overload was not a major concern. Therefore, FFP was selected as a safe alternative to PCC in an emergency setting. This approach allowed for timely intervention, while also preserving our patient’s safety. No pump thrombosis or ischemic complications occurred despite temporary anticoagulation interruption.

Intraoperative management was adjusted with the requirements of the LVAD in mind. Because the LVAD is preload-dependent, special attention was paid to avoiding hypovolemia and maintaining an adequate preload. Because the reliability of non-invasive methods of blood pressure measurement is limited in LVAD patients, invasive hemodynamic monitoring was utilized.

Throughout the procedure, the mean arterial pressure (MAP) was sustained within the LVAD-appropriate range (~70–90 mmHg), and normovolemia was ensured. Anesthesia considerations included minimizing sudden changes in systemic vascular resistance and swiftly addressing hypotension. With eventual hemodynamic instability or pump alarms in mind, echocardiographic support and immediate access to LVAD parameter assessment were constantly available. All intraoperative precautions and targets were established following consultation with the LVAD implantation center.

An open laparotomy was conducted, which revealed a strangulation of the small intestine within the sac of the umbilical hernia. A partial resection of the small intestine was performed with an end-to-end, hand-sewn double-layer anastomosis. In addition to bowel resection, the coexisting right-sided inguinal hernia was repaired during the same surgery. The repair was limited to a simple closure of the hernia defect without mesh implantation and without extensive dissection to reduce the risk of bowel incarceration in another hernia, which could have necessitated re-operation in an extremely high-risk LVAD patient. The procedure involved only peritoneal suturing; therefore, the operative time and the bleeding risk were not meaningfully increased, and this intervention was considered appropriate in this scenario. The surgery lasted 2 h 40 min. Estimated intraoperative blood loss was 600 ml and the postoperative drain output was about 500 mL. The histopathological examination of the specimen revealed hemorrhagic necrosis of the intestinal wall and the mesentery.

In the first 2 days of hospitalization, the patient started to develop symptoms of intraperitoneal bleeding, which corresponded to the rising INR (Figure 2). An abdominal ultrasound revealed free fluid in the intraperitoneal cavity, mostly on the right side – a 70-mm layer of fluid located below the inferior margin of the liver. Thus, a decision was made to totally withhold anticoagulant and antiplatelet medication and administer 2 units of pRBC and 1 unit of platelet concentrate (PC). The patient had become hemodynamically stable by the 5th day of hospitalization and on that day we decided to administer 40 mg of low-molecular-weight heparin (LMWH) subcutaneously (s.c.) every 12 h. On the 6th day, we administered 60 mg of LMWH s.c. every 12 h. Finally, on the 7th day of hospitalization, the dose of LMWH was increased to 80 mg s.c. every 12 h until the last day of hospitalization. We recommenced 75 mg of clopidogrel per os (p.o.) on the 8th day and 5 mg of warfarin p.o. on the 9th day. Clopidogrel and warfarin administration continued until the last day of hospitalization. The following days of hospitalization were uneventful. On the 11th postoperative day, he was transferred to the LVAD implantation center to continue cardiological treatment.

Discussion

LIMITATIONS:

Importantly, conclusions regarding the safety of anticoagulation interruption drawn from this single case cannot be generalized, as outcomes may vary based on device type, patient-specific factors, and the duration of anticoagulation interruption. Furthermore, publication bias toward favorable outcomes must be acknowledged.

Conclusions

The actual number of LVAD patients who will require emergency surgical treatment will probably remain unknown. To ensure the highest standard of care for these patients, a multidisciplinary approach to their management is imperative. Early consultation with the LVAD center is essential and general surgeons should be familiar with LVAD-specific physiological considerations. Anticoagulation must be individualized and dynamically titrated. It is also advisable to consult the specialized center overseeing the patient’s ongoing care and to implement a medication regimen appropriately tailored to their condition. While limited to a single experience, this report highlights practical management considerations and underscores areas of uncertainty that may inform clinical awareness and generate hypotheses for future investigation into the emergency surgical care of patients with LVADs.