Massive Bochdalek Hernia in an Adult Presenting With Cardiac Arrhythmias: A Case Report

Abstract

Adult Bochdalek hernia is a rare and often misdiagnosed congenital diaphragmatic anomaly that poses significant clinical risks due to the potential for visceral incarceration and strangulation. We report a case of a 20-year-old female patient with no prior medical history who presented with non-specific arrhythmias, an atypical clinical onset that led to the identification of a massive left-sided diaphragmatic hernia. Diagnostic imaging, specifically multidetector computed tomography, confirmed migration of the stomach, spleen, and bowel loops into the thoracic cavity, associated with pulmonary hypoplasia. The patient underwent an exploratory laparotomy, which revealed a 10-cm posterolateral diaphragmatic defect. Surgical management included hernia reduction, splenectomy due to vascular pedicle laxity, and diaphragmatic repair using a polytetrafluoroethylene prosthesis. Given the massive visceral volume and the resulting loss of abdominal domain, a staged surgical strategy with an open abdomen and negative pressure wound therapy was employed, ultimately achieving definitive closure with a split-thickness skin graft. This case underscores the diagnostic challenge posed by Bochdalek hernia in the adult population and highlights the importance of maintaining a high index of suspicion in the presence of atypical thoracic symptoms. Furthermore, it demonstrates that a timely, multidisciplinary approach involving advanced surgical techniques is essential to manage complications such as loss of abdominal domain and to ensure a favorable long-term prognosis.

Introduction

Among congenital defects, Bochdalek hernia (BH) represents one of the most critical anomalies of diaphragmatic development, characterized by the persistence of a hiatus in the posterolateral region of the diaphragm [1]. The highest incidence occurs on the left side (80-90%) due to early closure of the right pleuroperitoneal canal and the mechanical barrier effect exerted by the liver [1,2].

This defect originates during embryogenesis, specifically when the pleuroperitoneal membranes fail to fuse adequately with the transverse septum and the esophageal mesentery between the eighth and 10th weeks of gestation [1,3]. This establishes direct communication between the abdominal and thoracic cavities, allowing the positive intra-abdominal pressure gradient to drive the viscera into the thorax, where negative pressure predominates [2,3]. Crucially, the massive migration of abdominal viscera into the thoracic cavity can induce significant mediastinal shift and direct mechanical compression of the heart, triggering cardiac arrhythmias as an atypical clinical presentation [1,4].

In contrast to the neonatal presentation, which is typically associated with pulmonary hypoplasia and persistent pulmonary hypertension, BH in adults is a distinct clinical entity that often eludes early detection. Its presentation usually stems from a small defect that progressively increases in size due to factors that elevate intra-abdominal pressure, such as pregnancy, chronic physical exertion, or minor trauma, facilitating late visceral migration [5,6]. We report a case of a 20-year-old female patient with no known pathological history, whose clinical onset consisted of non-specific arrhythmias, leading to the diagnosis of a Bochdalek hernia during the diagnostic workup.

Case presentation

A 20-year-old female with no relevant past medical or surgical history presented with a two-month history of non-specific arrhythmias and dyspnea. Upon admission, the patient's cardiac assessment revealed tachycardia at 115 beats per minute (bpm) with an irregularly irregular rhythm; a 12-lead electrocardiogram (ECG) confirmed atrial fibrillation with a rapid ventricular response; blood pressure 110/70 mmHg; respiratory rate 22 breaths/min; and temperature 36.5°C. Laboratory investigation included a complete blood count, liver and renal function tests, and electrolytes, all of which were within normal limits. During the initial diagnostic workup at the primary care level, a posteroanterior chest X-ray revealed near-total opacification of the left hemithorax with radiolucent areas suggestive of intestinal loops (Figures 1A, 1B). A subsequent chest computed tomography (CT) scan confirmed the diagnosis of a left-sided diaphragmatic hernia with massive migration of abdominal contents, revealing a 10 cm diaphragmatic defect with herniation of the stomach, spleen, and small and large bowel loops, associated with ipsilateral pulmonary hypoplasia (Figures 2A-2C). Given the unequivocal CT findings demonstrating a massive mediastinal shift and direct physical compression of the cardiothoracic structures by the herniated viscera, the arrhythmia was attributed to this acute mechanical distortion. Consequently, the patient was referred to a tertiary care center for emergency surgical decompression to address the underlying anatomical etiology.

Figure 1. Preoperative and postoperative radiographic evaluation.

(A) Preoperative chest X-ray showing total opacification of the left hemithorax (white lung) with radiolucent areas consistent with herniated intestinal loops. (B) Immediate postoperative control evidencing partial lung re-expansion following hernia reduction and chest tube placement.

Figure 2. Computed tomography (CT) evaluation of the Bochdalek hernia.

(A) CT scan at the scapular level demonstrating migration of intestinal loops into the left hemithorax with contralateral displacement of the mediastinal structures. (B) CT scan at the T4 level showing displacement of the aortic arch and the presence of both small and large intestines within the thoracic cavity. (C) CT scan showing massive herniation of colonic loops into the left hemithorax.

Physical examination and surgical management

The patient was hemodynamically stable and afebrile, reporting dyspnea only during strenuous physical activity. Physical examination revealed absent breath sounds in the left hemithorax and audible peristaltic sounds in the same region; the abdomen was soft, flat, and non-tender, with no signs of peritoneal irritation.

An exploratory laparotomy was performed, confirming a 10 cm left posterolateral diaphragmatic defect. Intraoperative findings included incarceration of the splenic flexure, the upper portion of the descending colon, spleen, stomach, and small bowel. The defect was extended by 2 cm to facilitate safe reduction of the contents. The spleen was identified as part of the herniated viscera within the left hemithorax, causing significant anatomical distortion. The massive displacement and entrapment of the spleen resulted in extreme stretching, mechanical tension, and kinking of the splenic hilar vessels. Given the compromised vascular elasticity and the high probability of irreversible splenic ischemia and subsequent infarction, a primary decision for a splenectomy was made. This surgical step safely eliminated the risk of necrotic complications and permitted adequate access for the subsequent reduction of the remaining viscera and tension-free diaphragmatic repair.

Diaphragmatic repair was performed using a polytetrafluoroethylene (PTFE) prosthesis, secured with interrupted 2-0 polypropylene sutures. Given the restoration of visceral volume and the evident loss of abdominal domain, an open abdomen strategy was adopted to prevent abdominal compartment syndrome. An expanded PTFE (ePTFE) mesh was utilized for temporary closure, and a left-sided chest tube was inserted for the management of the pleural dead space (Figures 3A, 3B).

Figure 3. Surgical procedure showing diaphragmatic repair and open abdomen management.

(A) Repair of the 10-cm diaphragmatic defect using a PTFE prosthesis secured with interrupted sutures. (B) Initial management of the loss of abdominal domain using an expanded PTFE (ePTFE) mesh as a temporary closure (open abdomen).

The patient remained hospitalized for a total of six weeks. After confirming >90% lung re-expansion via a follow-up CT scan and observing a quantitative chest tube output of 100 mL/24 h, the tube was safely removed on postoperative day 14. In a second surgical stage performed on postoperative day 20, the temporary ePTFE mesh was removed, and negative pressure wound therapy (NPWT) was initiated. This therapy required four dressing changes over a period of 23 days until adequate granulation tissue was achieved, objectively reflecting progressive adaptation of the abdominal cavity and partial recovery of the abdominal domain. Throughout this process, the patient received total parenteral nutrition, followed by a successful transition to an oral diet. Definitive closure was achieved using a split-thickness skin graft (Figures 4A, 4B).

Figure 4. Staged management of the abdominal wall.

(A) Application of a negative pressure wound therapy (NPWT) system for the management of the surgical wound and granulation tissue. (B) Result following definitive closure of the abdominal wall defect using a split-thickness skin graft.

Notably, the patient experienced complete resolution of cardiac arrhythmias, with normalization to sinus rhythm by postoperative day 2 in the intensive care unit (ICU), and remained hemodynamically stable until discharge. At the three- and six-month follow-ups, the patient remained asymptomatic, with no recurrence of arrhythmias or respiratory symptoms. She remains under active follow-up by the general surgery and plastic surgery departments for ongoing abdominal wall reconstruction. A timeline was added to enhance the understanding of the clinical course and specific procedural intervals (Figure 5).

Figure 5. Clinical course and staged surgical management timeline.

Timeline of clinical events, illustrating the progression from initial atypical symptoms and arrhythmia onset to emergency surgical decompression, staged open abdomen management, and definitive wound closure.

Discussion

The clinical spectrum of Bochdalek hernia (BH) in adults is remarkably heterogeneous. While acute respiratory distress predominates in neonates, adults typically present with non-specific epigastric pain, postprandial fullness, or dyspnea [5,7]. However, the primary risk lies in the phenomenon of incarceration; the rigid hernial ring in adults increases the risk of strangulation, ischemic necrosis, and mediastinitis, with a mortality rate of up to 25% if timely intervention is not provided [6,8]. In our case, the diagnosis was secondary to the evaluation of arrhythmias, an atypical presentation that is poorly documented in the literature.

The mechanism of arrhythmias in this context is primarily mechanical. Massive herniation leads to significant mediastinal shift and thoracic anatomical distortion, mimicking conditions like tension pneumothorax [8]. This severe mass effect and physical displacement of mediastinal structures exert extrinsic compression on cardiac chambers, which serves as the mechanical trigger for rhythm disturbances and supraventricular arrhythmias, aligning with clinical reports of new-onset atrial fibrillation in adult patients presenting with massive left-sided Bochdalek hernias [4].

Differential diagnosis represents a critical area. Cases have been reported that were erroneously treated as pneumothorax, where the placement of chest tubes resulted in the perforation of herniated viscera [8,9]. Therefore, multidetector computed tomography (MDCT) with multiplanar reconstructions is considered the gold standard because it enables identification of the diaphragmatic interruption sign [2,4]. Regarding surgical management, while primary closure is the norm in pediatric populations, the use of prosthetic material is essential in adults for defects larger than 8 cm or when tissues are compromised [3]. Although various approaches exist (laparotomy, thoracotomy, or minimally invasive techniques), the choice depends on the patient's stability and the surgical team’s expertise [3].

The massive and prolonged migration of abdominal viscera into the thoracic cavity in this case led to a clinical scenario often described as loss of abdominal domain. Because the abdominal cavity physically adapts to the chronic absence of the herniated organs, the functional volume of the abdomen decreases significantly. Consequently, forceful primary reduction and immediate closure of the fascia are unfeasible, as the excessive tension would dramatically increase intra-abdominal pressure and precipitate abdominal compartment syndrome [10,11]. To mitigate this catastrophic physiological risk, employing a staged open-abdomen strategy, alongside temporary containment, negative pressure wound therapy, and gradual abdominal wall conditioning, enables safe anatomical adaptation before definitive delayed closure.

Finally, as a retrospective case report, this study inherently lacks the generalizability of larger clinical trials. Due to the emergent surgical need for immediate decompression, a comprehensive cardiological workup, such as an echocardiogram, was not performed to detail the mechanical impact on the cardiac chambers. Despite these limitations, this case highlights the importance of maintaining a high index of suspicion for Bochdalek hernia in adults presenting with acute cardiorespiratory symptoms. Ultimately, it reinforces the vital role of early cross-sectional imaging and staged surgical management in preventing catastrophic outcomes.

Conclusions

As demonstrated by the present case, atypical cardiac manifestations, such as arrhythmias, can arise from mechanical mediastinal compression in adult Bochdalek hernias, underscoring the need to look beyond primary pleuropulmonary pathologies. Computed tomography remains the gold standard for accurate diagnosis, allowing clinicians to avoid inappropriate interventions. For massive defects, a multidisciplinary, staged surgical approach prioritizing visceral decompression and safe abdominal wall management is essential to mitigate life-threatening complications and ensure favorable patient outcomes.