Incessant pericarditis

Article written and reviewed by Dr Luca Moretti

The incessant pericarditis is a course of pericardial disease in which the inflammatory episode does not achieve stable remission: symptoms persist or fluctuate, often becoming more pronounced when treatment is reduced, without a true symptom-free interval. In traditional terminology, the term has been applied to persistence beyond four to six weeks; contemporary classification distinguishes an acute phase within four weeks and chronic disease when duration exceeds three months. The defining feature of an incessant course, however, remains continuity of disease activity, not merely crossing a date on the calendar.

It is neither a specific etiology nor a synonym for prolonged chest pain. An acute pericarditis may fail to resolve because of insufficient control of the inflammatory response, persistence of the cause, or treatment that is not adequately tolerated; sometimes, however, reassessment shows that the residual disorder is no longer pericarditic. recurrent pericarditis requires a remission between distinct episodes. chronic pericarditis describes prolonged duration and may include different inflammatory or structural conditions: chronicity and incessant disease are not perfectly interchangeable terms.

The true frequency is difficult to quantify because many studies have grouped persistence and recurrence into a single outcome and referral centers receive a selected proportion of complex cases. It is therefore incorrect to assign to the incessant form the recurrence percentage observed after a first episode. Its clinical importance derives from the need for causal and therapeutic reassessment, the burden of medication exposure, and the risk that still-active disease may be mistaken for a succession of new attacks.

Causes of persistence, predisposing factors, and disease mechanisms

The first level of interpretation concerns persistence of the cause. An undrained bacterial infection, unrecognized tuberculosis, still-active autoimmune disease, or a neoplastic process can sustain inflammation despite temporary relief with analgesics or corticosteroids. Continued exposure to a causative drug or insufficient correction of the uremic setting may also prevent control. In these cases, failure to achieve remission does not demonstrate intrinsic resistance to an anti-inflammatory drug: it indicates that the causal process has not been addressed or that several mechanisms coexist.

A second level concerns the actual treatment. Doses that are too low, use only as needed, frequent interruptions, failure to introduce colchicine when indicated, and tapering before remission can leave the local response active. Diarrhea, dyspepsia, kidney injury, financial difficulties, or unclear instructions may result in exposure different from that intended. It is therefore inappropriate to call a disease resistant based only on the list of prescribed drugs. Adherence is reconstructed without blame, by verifying what was actually taken and which obstacles limited therapy.

The corticosteroid dependence represents a particular clinical pattern: disease reactivates when the dose falls below a certain level or cannot be discontinued without new signs of activity. Prompt disappearance of pain after increasing corticosteroids can perpetuate a cycle of dose escalation and reduction unless control is stabilized with an appropriate strategy. The association between steroid use and a more difficult course is also influenced by the fact that patients with more severe disease receive these drugs more often. Not every corticosteroid exposure causes an incessant course, and a corticosteroid appropriately indicated for a systemic disease should not itself be considered an error.

Among the predisposing factors are immune-mediated diseases, immunosuppression, recent cardiac injury, an uncontrolled secondary cause, and conditions that reduce the ability to use first-line therapy. Age, renal function, and polypharmacy often act through tolerability rather than through a greater intrinsic tendency of the pericardium to become inflamed. Persistently elevated CRP, an enlarging effusion, and inflammatory imaging abnormalities are instead indicators of activity or risk. A subacute onset and lack of response after one week should already prompt reassessment, without waiting to reach the formal four-to-six-week threshold.

When no maintaining cause is identified, a plausible model is failure of immune resolution after the initial trigger. Injured tissue releases damage signals that sustain recruitment and activation of innate immune cells; locally produced mediators attract additional cells and increase vascular permeability. The interleukin-1 axis may contribute to this circuit. Interleukin-1 alpha released in relation to tissue injury and interleukin-1 beta matured through pathways that include the inflammasome may promote a self-sustaining inflammatory response. The relative contribution of these mechanisms varies and cannot be measured by a single routine blood test.

The involvement of NLRP3 documented in translational research provides a biological basis for some therapies, but is not a diagnostic criterion for incessant pericarditis. Likewise, a response to interleukin-1 blockade does not retrospectively identify a genetic mutation. Adaptive immunity may be relevant when antigens exposed by injury or an autoimmune disease sustain the response. For this reason, phenotypes with fever, marked CRP elevation, and polyserositis do not necessarily coincide with those dominated by a documented connective tissue disease or by pain with modest systemic expression. These groups may overlap and change during treatment.

Within the pericardium, exudation and deposition of fibrin may continue while normal clearance and repair processes fail to fully restore the serosal surfaces. Organized fibrin may promote adhesions; fibroblast activation and matrix deposition make the tissue less compliant. Progression to irreversible fibrosis is not inevitable, however: a substantial component of thickening may be due to reversible edema and inflammation. This distinction explains why persistent symptoms require assessment of disease activity and function, not merely an anatomic description of thickness.

The hemodynamic pathophysiology depends on the phenotype. Painful disease without a significant collection may leave cardiac filling normal; an enlarging effusion may increase pressure within the sac; an inflamed, poorly compliant pericardium may cause exaggerated ventricular interdependence and constrictive signs. The resulting congestion may involve the liver, kidneys, and gastrointestinal tract, causing edema, ascites, reduced filtration, and early satiety. None of these effects can be inferred from duration alone. Concomitant myocardial injury may also contribute to dyspnea and must be distinguished from purely pericardial limitation.

Clinical manifestations and reconstruction of the course

The central historical feature is continuity of symptoms. It is necessary to reconstruct whether the pain ever disappeared, for how long and with which therapy, and whether the other initially abnormal findings normalized during the same period. Reduction of pain from severe to mild does not equal remission. Nor do a few better days on a high corticosteroid dose automatically demonstrate a new episode when pain returns. The timeline should include onset dates, dose changes, test results, and physical activity, because temporal sequence is part of the diagnosis.

The persistent pain may retain pleuritic and positional features or become less typical over the course of weeks. It may interfere with sleep, deep breathing, and trunk movements. This change requires attention: a new location, a component reproducible by palpation, or a predominant relationship with meals suggests possible coexisting causes. Persistent pericarditis does not protect against reflux, chest-wall disease, ischemia, or pulmonary embolism. A new symptom should not automatically be attributed to the established diagnosis.

The fever, when persistent or recurrent, should be correlated with drug doses, CRP, and extracardiac findings. Corticosteroids may blunt fever even in the presence of infection; conversely, a new intercurrent infection may raise CRP without pericardial reactivation. Night sweats, weight loss, lymphadenopathy, or prolonged fever require etiologic reassessment. Arthritis, rash, mucosal ulcers, and abdominal symptoms may reveal over time a systemic phenotype that was not evident at onset. Late appearance of these features changes the meaning of a previous idiopathic diagnosis.

The dyspnea is particularly important when progressive because it may reflect increasing fluid, impaired filling, anemia, drug effects, or myocardial involvement. Orthopnea, weight gain, edema, and abdominal distension require assessment of congestion. Reduced exercise capacity after weeks of inactivity may also be due to deconditioning, which should not immediately be mistaken for hemodynamic deterioration. Palpitations and presyncope warrant investigation for an underlying rhythm disturbance, especially when associated with elevated troponin or impaired ventricular function.

The physical examination assesses vital signs, perfusion, and volume status, repeating auscultation for a friction rub that may appear and disappear. Persistent tachycardia should be interpreted together with pain, temperature, anemia, and cardiac function. Jugular venous distension, hepatomegaly, ascites, and an inspiratory rise in venous pressure may indicate constrictive physiology or other causes of right-sided heart failure. Pulsus paradoxus points toward hemodynamically significant respiratory interaction, but its absence is not enough to exclude a compressive collection. Examination of the abdomen and lower limbs completes the thoracic assessment.

The search for adverse effects is an integral part of the examination. Hypertension, weight gain, Cushingoid facies, bruising, and proximal weakness may indicate the cost of steroid therapy; pallor and digestive symptoms may suggest bleeding; dehydration from diarrhea can worsen renal function. These findings affect strategy and sometimes explain part of the symptoms attributed to the disease. An accurate history should therefore describe pericardial activity, functional impairment, and toxicity separately, rather than grouping everything under the generic label of resistant pericarditis.

Assessment also includes sleep and daily functioning. Uncertainty about duration, repeated healthcare visits, and fear of worsening may increase attention to symptoms and restrict activity. Recognizing this burden does not mean reducing a physical disorder to a psychological cause. It helps identify which goals matter to the patient and supports a sustainable recovery plan. A simple diary of pain, fever, and treatment changes may help reconstruct the course, whereas obsessive recording without a clinical purpose risks increasing alarm without improving decisions.

Diagnostic confirmation and distinction from mimicking conditions

Diagnosis requires verification of two components: a documented pericarditis and a course without adequate remission. There is no biomarker specific to incessant disease, nor an independent set of criteria that turns any pain lasting more than a month into pericardial disease. Evidence from the first episode is therefore reassessed and signs of current activity are sought. Summary labels such as 'previous pericarditis' do not replace the original ECG, imaging, and data, especially when the initial diagnosis was based only on pain or on a minimal incidental effusion.

The criteria of scientific societies remain applicable to determine whether the clinical picture is pericarditic. The 2025 ACC consensus requires pleuritic pain or an equivalent suggestive clinical presentation, associated with at least one additional finding. The following list concerns the diagnosis of pericarditis; the definition of incessant disease is added on the basis of the timeline. Duration, response to corticosteroids, and the mere repetition of medical visits are not additional official diagnostic criteria.

Additional findings accompanying a compatible clinical presentation in the 2025 ACC diagnostic pathway.

• Pericardial friction rub detected on physical examination.
• Characteristic electrocardiographic changes.
• Elevated inflammatory markers.
• New or increased pericardial effusion.
• Evidence of pericardial inflammation on imaging.

Longitudinal interpretation is essential. A residual ECG with T-wave inversion may reflect evolution of the first episode rather than proving new activity; a stable small effusion may persist after inflammation resolves. Conversely, new abnormalities, an enlarging collection, or recurrence of a friction rub provide dynamic information. Comparison with previous examinations is often more useful than an isolated sophisticated test. When comparable data are lacking, it is preferable to describe this limitation rather than confidently attributing findings of uncertain age to the present.

The serial CRP is useful when it was elevated at onset, but must be interpreted together with symptoms and treatment. A normal CRP while taking prednisone or receiving cytokine-pathway blockade does not have the same meaning as spontaneous normalization at a distance from the active phase. Some patients may have predominantly local inflammation with only a modest systemic response. Conversely, a high value may be caused by infection, autoimmune disease, or another inflammatory focus. Complete blood count, renal and hepatic function, and troponin when appropriate answer different questions: toxicity, comorbidity, organ involvement, and myocardial injury should not be merged into a single indicator.

The Doppler echocardiography evaluates changes in the amount and distribution of fluid, compression, and signs of constriction. Respiratory septal motion, variations in atrioventricular inflow, annular velocities, and hepatic venous flow are interpreted together. An isolated sign may depend on loading conditions or respiration. Left- and right-ventricular function should be compared over time because deterioration may shift the problem toward concomitant myocardial involvement. An echocardiogram without effusion, however, does not resolve the question of inflammation of the pericardial layers.

The cardiac magnetic resonance imaging has a particular role when pain continues, CRP is poorly informative, and an important therapeutic decision depends on demonstrating activity. Pericardial edema and enhancement, the distribution of abnormalities, and possible myocardial findings contribute to assessment. LGE is not a binary switch: it may persist in altered tissue and does not automatically require indefinite maintenance of medication. The combination of edema, clinical findings, and temporal course is more persuasive than a positive image considered alone. Magnetic resonance imaging must also be interpreted in relation to the disease phase and the treatment being taken at the time of the examination.

Among mimicking conditions are costochondral pain, muscular disorders, pleuritis, reflux, and esophageal disorders, in addition to acute cardiopulmonary causes that must be reconsidered if the clinical picture changes. After prolonged corticosteroid therapy, fatigue, myalgia, and malaise during tapering may also be due to hypothalamic-pituitary-adrenal axis suppression or withdrawal syndrome. These symptoms should not be interpreted by automatically increasing immunosuppression. Pain may also persist without objective signs of activity, requiring dedicated assessment that neither denies its reality nor exposes the patient to drug escalation without a demonstrated target.

Further investigations, phenotype, and organ damage

Once persistent activity has been confirmed, etiologic reassessment should search for findings that could change treatment. It does not consist of automatically repeating every previously negative test. Evaluation starts from new clinical features, the quality of the initial work-up, and probabilities related to age, geographic origin, exposures, and comorbidities. An apparently viral episode that persists with fever, an enlarging collection, and weight loss requires different reasoning from mild pain with normal markers and stable imaging. Time may make recognizable a cause that was not yet evident at onset.

The infections deserve attention before any escalation of immunosuppression. If fever and suspected bacteremia are present, blood cultures and a search for sources are considered; if epidemiology suggests tuberculosis, infectious-disease assessment and appropriate testing are integrated. Fluid obtained for a clinical indication may permit microbiologic and cytologic studies. Indiscriminate serologic testing does not compensate for a low pre-test probability and does not by itself prove pericardial localization. A finding compatible with infection must be clarified before being labeled as expression of generic autoinflammation.

The search for systemic autoimmunity is guided by symptoms and involved organs. Urinalysis, proteinuria, renal function, complete blood count, complement, and selected autoantibodies may contribute when suspicion is justified. Polyserositis with arthritis and urinary abnormalities has a different meaning from an isolated low-titer ANA. In forms with periodic fevers, family history, early onset, or multisystem attacks, an autoinflammatory evaluation and, when indicated, genetic testing are considered instead. Sequencing is not a universal test for every persistence of pain, and a variant of uncertain significance is not sufficient to diagnose an inherited syndrome.

The inflammatory phenotype is described on the basis of fever, CRP, effusion, serositis, and imaging, specifying what is spontaneous and what is attenuated by medication. In phenotypes with marked inflammatory activity, interleukin-1 blockade has a more direct rationale. When autoimmune disease predominates, the choice must account for the entire systemic picture. If inflammatory expression is limited, documenting local activity is particularly important before increasing immunomodulation. These categories guide decision-making but are not impermeable compartments or tests that can predict response with certainty.

Definition of organ damage includes assessment of biventricular function, congestion, rhythm, and renal and hepatic function. An increase in creatinine may be due to NSAIDs, dehydration, pre-existing kidney disease, or congestion: the mechanism changes the therapeutic choice. Liver abnormalities may reflect congestion, medication, or systemic disease. If Doppler suggests constriction and magnetic resonance imaging shows inflammation, potential reversibility under therapy is assessed without indefinitely postponing a necessary intervention in a persistently hemodynamically significant form. Calcifications on CT support structural damage, but do not by themselves quantify the impairment of filling.

Invasive procedures are reserved for selected questions. Drainage addresses compression, suspected infection, specific diagnostic indications, or other clinical problems related to the collection; biopsy may be considered when a tissue diagnosis is plausible and would change management. Hemodynamic catheterization can clarify constrictive physiology not resolved by imaging. Before biological therapy, appropriate safety testing is also performed, including assessment of infectious risk and baseline hematologic and biochemical tests. The purpose of these checks differs from demonstrating pericarditis and should remain explicit.

Therapeutic strategy, remission, and prognosis

Treatment begins by correcting documented reasons for incomplete control. If first-line therapy was taken intermittently or at insufficient doses, a sustainable regimen is reconstructed; if tolerability prevents this, a justified alternative is chosen. In appropriate patients, aspirin or an NSAID is used at a regular anti-inflammatory dose, with gastric protection and monitoring of renal function. Response should include progressive control of symptoms and objective findings. Continuing an ineffective prescription for months without reassessing the target is not a maintenance strategy.

Usual adult doses, to be adapted to individual circumstances, include ibuprofen 600-800 mg every eight hours or aspirin 750-1,000 mg every eight hours. In incessant disease, the main issue is when and how to taper: reduction begins after control has been achieved, and a flare requires verification of activity and causes before identical courses are repeated. Combining multiple NSAIDs does not overcome an inadequate response and increases risk. In patients with nephropathy, heart failure, or major bleeding risk, this strategy may need to be avoided even if it would theoretically be effective against inflammation.

The colchicine retains a background role when it can be used. The usual regimen is 0.5 mg daily in patients weighing less than 70 kg and 0.5 mg twice daily at 70 kg or above, with adjustments for age, renal and hepatic function, interactions, and tolerability. In incessant cases, contemporary recommendations generally call for at least six months, with duration reassessed according to the course. Its effect is not limited to immediate analgesia: it helps stabilize inflammatory control. For this reason, disappearance of pain within a few days does not justify early discontinuation. Gastrointestinal adverse effects require review of dose and safety, not forced continuation.

If a corticosteroid is necessary, the lowest initial dose capable of controlling the clinical picture is used, often within the prednisone range of 0.2-0.5 mg/kg/day, after infection has been considered. Tapering begins only during a stable phase and becomes more cautious at low doses, where small proportional reductions may be clinically relevant. Below approximately 15 mg/day, reductions of about 1.25-2.5 mg spaced several weeks apart are often required, adapted to the patient's history. This is not a table to be applied blindly: duration of exposure, adrenal axis function, underlying disease, and signs of activity may require different rates.

The principle of sequential tapering helps identify which change is tolerated. Whenever possible, all drugs are not reduced simultaneously; colchicine is generally maintained while other anti-inflammatory drugs are tapered and for a period of stability. In a person already dependent on corticosteroids, repeated dose increases for every isolated pain episode may worsen the problem. If objective inflammation persists, early discussion of therapy capable of reducing the steroid requirement is appropriate. It is not necessary to accumulate months of toxicity to demonstrate that the course warrants specialist assessment.

The interleukin-1 blockade is an important option in inflammatory incessant forms not controlled by conventional treatment, especially in the presence of corticosteroid dependence. Selection requires confirmation of activity and a reasonable etiologic work-up, because an untreated infection must not be masked as immune resistance. The strongest randomized trials, AIRTRIP and RHAPSODY, concern selected populations with recurrent pericarditis; their application to incessant disease is integrated with clinical experience and recommendations, without presenting those studies as evidence dedicated to every persistent form.

The anakinra antagonizes the interleukin-1 receptor and is commonly used in adults at a dose of 100 mg subcutaneously daily; conditions such as severe renal impairment may require changes in the dosing interval. rilonacept binds interleukin-1 and, in the adult regimens studied, uses an initial dose of 320 mg followed by 160 mg weekly. Choice takes into account evidence, availability, local regulatory conditions, preferences, and clinical profile. These are not interchangeable doses, nor are they therapies to be stopped and restarted independently in response to daily pain. Duration and the method of discontinuation are planned according to the stability achieved.

Before and during these therapies, infectious risk, complete blood count, liver function, and other drug-appropriate parameters are assessed, including the lipid profile for rilonacept. Injection-site reactions are common, especially with anakinra; infections and hematologic abnormalities require surveillance. Vaccination management, particularly for live vaccines, should be planned before immunomodulation. The IRAP registry associated a longer period at full dose and a more prolonged gradual taper with a lower relapse risk during anakinra treatment; because this is observational evidence, it does not establish an identical optimal duration for everyone.

Azathioprine and other immunomodulators may be considered when the phenotype and systemic disease make them appropriate; azathioprine has a slow effect and is not a drug for immediately stopping pain. intravenous immunoglobulins are a rescue option in selected patients, supported mainly by case series and cohorts rather than by a randomized evidence base comparable to that of anti-interleukin-1 agents. The multicenter cohort by Collini and colleagues published in a 2026 volume expands experience in refractory recurrent forms, but does not resolve the question of the best sequence for all incessant cases. The choice remains individualized and specialist-driven.

A specific cause requires specific therapy, possibly together with symptom control. A purulent collection requires drainage and antibiotics; tuberculosis requires an antimycobacterial regimen; autoimmune activity requires a strategy coordinated with the organ disease. Drainage, however, is not a general treatment for incessant pericarditis without an indication related to the collection. Pericardiectomy has a role in symptomatic irreversible constriction and, much more selectively, in refractory disease that cannot be controlled with medication after diagnostic verification at an expert center. Failure to respond to a single drug does not justify direct progression to surgery.

The remission is assessed by combining symptoms, examination, markers when informative, and imaging in cases that require it. Follow-up is closer during treatment changes and tapering and should also assess function, sleep, and adverse effects. Intense exercise is suspended during active disease; recovery is gradual and based on documented control, with a distinct pathway when myocardial injury is present. Prognosis may remain favorable in terms of survival even when the disease causes substantial morbidity. Symptom duration alone does not predict tamponade or constriction: etiology, hemodynamics, and objective response remain decisive.

Complications of persistent disease and treatment

The progression of effusion requires attention because it may be gradual and initially well tolerated. If accumulation exceeds the adaptive capacity of the sac, filling becomes impaired and tamponade may develop. Risk cannot be inferred from the duration of inflammation alone: rate of accumulation, distribution, and hemodynamic status are decisive. Increasing dyspnea or new tachycardia during treatment should therefore be evaluated before being attributed to deconditioning or anxiety. Loculated collections can cause regional compression and may require an approach different from that used for a free-flowing effusion.

The constrictive physiology may appear while inflammation is still reversible or may reflect a more stable fibrotic transformation. Recognizing it early makes it possible to determine whether adequate anti-inflammatory therapy normalizes filling. Improvement in pain without reduction of congestion does not equal hemodynamic resolution. Persistent ascites, edema, or congestive renal dysfunction requires reassessment of the mechanism and therapeutic indications. The effusive-constrictive form combines a collection with limitation from the visceral pericardium: draining the fluid may not completely correct filling pressures.

The cumulative toxicity becomes particularly relevant when the disease does not resolve. Prolonged NSAID use may promote gastrointestinal injury, bleeding, hypertension, and worsening renal function; the latter may further increase the risk of colchicine toxicity. Uncontrolled diarrhea may cause dehydration and alter drug exposure. With corticosteroids, metabolic, infectious, bone, ocular, and muscular risks increase over time. Prevention of osteoporosis and other harms should be assessed according to dose, duration, and individual risk, not postponed until a clinical complication appears.

The immunosuppression may modify the presentation of infections by blunting fever and the inflammatory response, making reassessment of new symptoms essential. An apparent flare during biological therapy does not immediately prove that the drug has lost efficacy: intercurrent infection, interruption, incomplete administration, and alternative diagnoses should be considered. Escalation without verification may amplify an avoidable risk. Likewise, abrupt steroid withdrawal after prolonged exposure can cause adrenal insufficiency or withdrawal symptoms and must be distinguished from recurrence of inflammation.

A common consequence is functional disability, which may persist beyond improvement in test results. Prolonged rest, loss of conditioning, sleep disturbance, and fear of movement may limit occupational and social recovery. A return-to-activity program proportional to remission, together with a reasoned reduction in medication burden, helps prevent biological control from remaining disconnected from personal recovery. Quality of life is not a negligible secondary outcome when disease lasts for months and requires repeated treatment.

Finally, prevention of complications depends on timely reassessment of any change. Syncope, hypotension, increasing dyspnea at rest, persistent fever, signs of infection, or new congestion require urgent evaluation. During stable periods, scheduled visits with explicit goals are more useful than continuous ad hoc adjustments. Documenting what remains inflammatory, what is structural, and what is a treatment effect helps avoid both premature discontinuation and therapy prolonged beyond its actual benefit.

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