Case report explores cSIS reinforcement for large PPDH repair

A newly published case report in Animals details repair of a large congenital peritoneopericardial diaphragmatic hernia in a dog using a canine small intestinal submucosa patch to reinforce closure of the defect. The patient, a 2-year-old intact female White Miniature Schnauzer weighing 6.23 kg, was evaluated for a month-long history of panting and exercise intolerance. Imaging confirmed PPDH with liver herniation into the pericardial sac, and surgeons determined the defect was too large for primary closure alone. (mdpi.com)

PPDH is a congenital communication between the peritoneal and pericardial cavities and is considered the most common congenital pericardial disease in dogs and cats. Some animals are diagnosed incidentally, while others present with respiratory or gastrointestinal signs, depending on which organs are displaced and whether there is entrapment or adhesion formation. Standard treatment is surgical reduction and repair in clinically affected patients, but large defects can be difficult to close without tension, especially when there is limited native diaphragmatic tissue. (merckvetmanual.com)

In this case, the authors used cSIS as a biologic reinforcement material after primary repair. According to the report summary, the dog later experienced marginal reherniation, prompting revision surgery. At reoperation, the surgeons found tissue at the cSIS application site that they believed represented remodeled self-tissue, and they were able to complete a successful second repair. That sequence makes the report notable: it does not present the technique as complication-free, but instead offers a detailed look at how biologic reinforcement behaved over time in a real clinical setting. (mdpi.com)

The report arrives as surgeons continue to look for workable options for oversized congenital defects. A 2024 Journal of the American Veterinary Medical Association case report described a ventral diaphragmatic advancement technique after failure of a pericardial flap repair in a Labrador Retriever with large PPDH, underscoring that no single approach has emerged as the standard for these challenging cases. Older literature has also explored small intestinal submucosa in diaphragmatic reconstruction models, supporting its role as a scaffold for tissue ingrowth rather than a permanent inert implant. (pubmed.ncbi.nlm.nih.gov)

Direct expert reaction to this specific paper was limited at the time of writing, but the broader clinical literature helps frame the significance. Reference sources from ACVS and Merck emphasize that chronic herniation can lead to adhesions, compromised blood supply, and technically demanding surgery, while recent case literature shows the range of complications clinicians may encounter, from pneumopericardium after repair to rare acute presentations such as liver lobe torsion with cardiac tamponade. In that context, any technique that expands the reconstructive toolkit for large PPDH defects is likely to draw interest from surgeons managing referral-level congenital cases. (acvs.org)

Why it matters: For veterinary professionals, this case is less about declaring a new standard of care and more about adding a practical data point in a thin evidence base. Large PPDH defects are uncommon, and the literature is dominated by single-case reports and technical notes. This report suggests biologic patch reinforcement with cSIS may be a reasonable option when primary closure is under tension, but it also reinforces the need to counsel pet parents about recurrence risk, revision surgery, and the uncertainty that comes with novel or infrequently reported techniques. (mdpi.com)

The case may also be useful for case selection and postoperative planning. Because many PPDH patients are diagnosed through thoracic radiography, ultrasound, echocardiography, or CT, and because some remain asymptomatic for long periods, clinicians may increasingly face decisions about when to refer, how aggressively to intervene, and which reconstructive method best fits the defect. Reports like this can help inform those discussions, even if they don't yet answer comparative questions on durability, cost, or complication rates. (merckvetmanual.com)

What to watch: The next meaningful step will be whether this technique appears in additional case reports or small case series, ideally with longer follow-up and clearer comparisons against pericardial flap repair, diaphragmatic advancement, and other biologic or synthetic reinforcement strategies in large congenital defects. (mdpi.com)