PPS: Post Pericardiotomy Syndrome
Submitted By: Dr. Michael Patterson
Pericardiotomy: cutting open the delicate sac in which the heart is contained
Syndrome: a set of signs (appearances) and/or symptoms (complaints) which occur together
What is PPS?
Post pericardiotomy syndrome is a troublesome postoperative complication of cardiac surgery. It is most often associated with a prolonged hospitalization in at least 25% of cardiac surgery patients. Recognized since the early days of heart surgery, the syndrome has also been described as: post comissurotomy syndrome, post perfusion/pump syndrome, post myocardial infarction (Dressler`s) syndrome and post pacemaker syndrome. PPS has even been described following a stab wound to the chest or after a heart biopsy when the pericardium (sac surrounding the heart) has been "nicked" or punctured. This syndrome seems to be triggered in some way by a break in the pericardial integrity allowing "something" in or out of a normally sealed environment around the heart.
The diagnoses of PPS is a challenge as it consists of fever, chest pain and lung tissue inflammation, all of which are consequences of heart surgery, related to infection or tissue trauma, chest incisions and anaesthesia or pre-existing congestion from the heart defect.
Syndromes are very common in medicine and surgery. In everyday life we may come across chronic fatigue syndrome and may even devise our own such as "Monday morning syndrome". The latter refers to the school age child with a headache, abdominal pain and tiredness which never occur on weekend mornings or while on vacation. One may appreciate there may not always be all the features in any one case-perhaps just abdominal pain on a Monday morning always improving as the school bus disappears into the distance. So it is in PPS, there may just be wet lungs and irritability or just shoulder pain.
Signs and Symptoms
Signs (appearances) and symptoms (complaints) of PPS include: fever, chest pain and lung inflammation. These are the principal problems, but the inflammatory reaction which seems to be the root of PPS may involve the nervous system resulting in irritability and ill defined neurological abnormalities such as disturbed consciousness and hallucinations; the gastrointestinal tract with loose stool and abdominal pain and skin and musculoskeletal system with rash and joint pains.
The syndrome was initially readily recognized following relatively minor procedures such as ASD repair and pacemaker implants where rapid uncomplicated recovery was anticipated. Just when the patient was starting to mobilize and feel better, things "fell apart"; fever, without apparent evidence of infection, chest pain out of all proportion to that normally accompanying breastbone or rib incisions, and cough or lung problems often resulting in decreasing oxygen saturations.
The characteristics of the pain are typically pericardial, which is "referred" to the stomach, shoulders, left arm, back, neck, or either side of the chest as there is no site in the brain`s body image for the heart and its covering. The inflammation will often result in increased drainage from chest tubes, if still in place and it is often milky or chylous as the underlying process of PPS seems to have a preference for the lymphatic channels. There may be a build up of fluid around the lungs in the pleural space, or around the heart in the pericardium if the drainage tubes have already been removed.
Most major operations involve a wide incision or even removal of the pericardial sac so any fluid generated around the surface of the heart in these cases will seep into the lung spaces or even into the abdomen.
Among the additional problems caused by this inflammatory process are atrial and ventricular arrhythmias, a predisposition to "Staph" infection of the tissue and shock like symptoms in some instances.
How common is the syndrome?
Between 20 and 40% of patients undergoing heart surgery may experience PPS. However, there are considerable unexplained differences between major centres.
Who gets PPS?
Probably any age group is susceptible to PPS. It was once thought that infants were spared of this syndrome, but this is likely because they cannot describe their shoulder pain and they generally have more serious underlying problems masking the PPS.
How do we test for PPS?
There is no specific test for PPS. White blood cells and platelets may sometimes increase dramatically as can the ESR, a non-specific marker for inflammation. Chest x-ray changes of fluid around or in the lungs, often mimicking congestive heart failure, are considered by many as one of the earliest and most sensitive laboratory tests, and if there is any fluid build up around the heart it will produce an enlarging heart shadow on the x-ray or be detected by cardiac ultrasound (echo).
Returning to our other example of a syndrome, where abdominal pain is often a prominent complaint, we must always try and exclude causes such as appendicitis before settling for Monday morning syndrome and treat accordingly.
How do we treat PPS?
The effects of PPS, such as excessive fluid around the heart, in or around the lungs, are treated sometimes urgently by drainage or cautious diuretic administration; oxygen and even reinstitution of ventilation (breathing machine) may be required. Treating the underlying inflammation is usually done with aspirin, non-steroidal anti-inflammatory drugs or steroids (prednisone).
How long does it last?
PPS usually lasts for just a few days but can occur for up to three to four months, often with fluctuations in severity. In rare cases, PPS grumbles on for years after the surgery, and occasionally scarring will result in constriction of the pericardial sac, which interferes with heart relaxation and therefore physical performance.
PPS can be thought of as an over reaction of the body to an as yet unidentified stimulant following a breach in the protective membrane around the heart. As in many immune or allergic illnesses the course may be mild or stormy and unpredictable. It should be considered whenever otherwise unexplainable complications including fever, chest pain and lung inflammation occur following heart surgery.