Overview
Definition:
Pericardiectomy is a surgical procedure involving the removal of part or all of the pericardium, the double-layered sac surrounding the heart
It is primarily indicated for conditions that impair cardiac function due to pericardial constriction, such as constrictive pericarditis or, less commonly, pericardial effusion causing tamponade refractory to other management.
Epidemiology:
Constrictive pericarditis, the main indication for pericardiectomy, is relatively rare
Its incidence varies globally and is often linked to underlying etiologies such as tuberculosis, viral infections, radiation therapy to the chest, cardiac surgery, autoimmune diseases, and idiopathic causes
Male patients tend to be more affected
Surgical outcomes are generally good, but mortality can be higher in cases with severe pre-operative cardiac dysfunction or multi-organ involvement.
Clinical Significance:
Pericardiectomy is crucial for relieving the restrictive physiology imposed by a thickened, fibrosed, or calcified pericardium
This restriction impairs diastolic filling of the ventricles, leading to elevated diastolic pressures, reduced cardiac output, and symptoms of right-sided heart failure
Successful pericardiectomy restores normal ventricular filling dynamics, alleviates symptoms, and improves long-term survival and quality of life for patients with severe constrictive pericarditis.
Indications
Primary Indications:
Symptomatic constrictive pericarditis unresponsive to medical management
This includes patients with severe dyspnea, peripheral edema, ascites, and hepatomegaly due to impaired diastolic filling.
Other Indications:
Recurrent pericardial effusion causing tamponade refractory to pericardiocentesis or medical therapy
Pericardial masses requiring excision
Management of encasing pericardial tumors or advanced fungal infections of the pericardium.
Contraindications:
Absolute contraindications are rare but include irreversible severe biventricular dysfunction with pulmonary hypertension and severe comorbidities that make surgery prohibitive
Relative contraindications may include active systemic infection, significant coagulopathy, or widespread malignancy.
Preoperative Preparation
Diagnostic Workup:
Thorough clinical evaluation including detailed history and physical examination
Echocardiography to assess pericardial thickness, calcification, ventricular diastolic function, and chamber dynamics
Cardiac catheterization for precise measurement of filling pressures and differentiation from restrictive cardiomyopathy
CT or MRI of the chest to visualize pericardial thickening, calcification, and involvement of adjacent structures.
Medical Optimization:
Diuretic therapy to manage fluid overload and edema
Optimization of cardiac function with inotropic support if necessary
Management of any underlying etiologies such as infection or autoimmune disease
Correction of electrolyte imbalances and coagulopathies.
Anesthesia Considerations:
General anesthesia with invasive hemodynamic monitoring is essential
Arterial line, central venous catheter, and pulmonary artery catheter may be used for monitoring
Careful fluid management is critical due to the impaired preload dependency of the heart.
Procedure Steps
Surgical Approaches:
The most common approach is a median sternotomy, providing excellent exposure of the heart and pericardium
Thoracotomy or video-assisted thoracic surgery (VATS) approaches are also utilized, particularly for less extensive disease or in select cases
Minimally invasive approaches can reduce morbidity but may offer less direct visualization.
Pericardial Dissection:
The dissection begins by identifying the thickened pericardium and carefully separating it from the epicardium
This is a critical step, as inadvertent injury to coronary vessels, phrenic nerves, or myocardial surface can lead to significant complications
The dissection typically proceeds from the diaphragmatic surface upwards and around the great vessels.
Removal Of Pericardium:
The goal is to remove as much thickened, calcified, and constricting pericardium as possible, particularly from the atria, ventricles, and atrioventricular grooves
The phrenic nerves must be meticulously identified and preserved
Complete decompression of the ventricles is paramount for successful outcome.
Hemostasis And Drainage:
Meticulous hemostasis is achieved
Chest tubes or drains are placed in the pericardial space and pleural cavities to manage residual bleeding, effusion, and pneumothorax
The sternum is closed in layers.
Postoperative Care
Icu Monitoring:
Patients are typically transferred to the Intensive Care Unit (ICU) for close hemodynamic monitoring
This includes continuous ECG, arterial blood pressure, central venous pressure, and oxygen saturation
Serial echocardiograms are performed to assess ventricular function and rule out residual effusions.
Pain Management:
Adequate pain control is essential to facilitate deep breathing and mobilization
Intravenous analgesics, patient-controlled analgesia (PCA), and epidural anesthesia may be used.
Respiratory Support:
Early mobilization and incentive spirometry are encouraged to prevent atelectasis and pneumonia
Mechanical ventilation may be required initially in some patients with significant pre-operative respiratory compromise.
Fluid Management:
Careful fluid balance is crucial
Patients may initially have low cardiac output and may benefit from modest fluid administration, but overhydration can lead to pulmonary congestion
Diuretics may be restarted as needed once hemodynamic stability is achieved.
Complications
Early Complications:
Hemorrhage requiring reoperation
Cardiac tamponade from residual or recurrent effusion
Myocardial injury from aggressive dissection
Arrhythmias, including atrial fibrillation and ventricular tachycardia
Respiratory complications such as pneumonia or pneumothorax
Renal dysfunction.
Late Complications:
Recurrent pericardial constriction, particularly if complete pericardiectomy was not achieved
Chronic right-sided heart failure
Hepatic congestion
Phrenic nerve dysfunction
Incisional hernia or infection.
Prevention Strategies:
Careful surgical technique to minimize myocardial and vascular injury
Meticulous dissection and identification of critical structures like coronary arteries and phrenic nerves
Complete removal of constricting pericardium
Effective postoperative fluid management and early mobilization
Prophylactic antibiotics and adherence to sterile techniques.
Prognosis
Factors Affecting Prognosis:
The degree of pre-operative cardiac dysfunction is the most significant predictor of outcome
Patients with preserved ejection fraction and lower pre-operative filling pressures generally have better prognoses
The etiology of pericarditis and the presence of multi-organ dysfunction also influence outcomes
The extent of pericardial resection is critical.
Outcomes:
Following successful pericardiectomy, significant symptom relief and improved quality of life are expected in a majority of patients
Hemodynamic parameters typically normalize, with reduced right atrial and ventricular pressures and improved cardiac output
Long-term survival rates are significantly improved compared to medically managed patients with severe constriction.
Follow Up:
Regular clinical follow-up is necessary to monitor for symptom recurrence, assess cardiac function, and manage any residual or late complications
Echocardiography is the primary modality for long-term surveillance
Patients may require ongoing medical management for heart failure symptoms or arrhythmias.
Key Points
Exam Focus:
Understand the primary indication (symptomatic constrictive pericarditis) and the pathophysiology of reduced diastolic filling
Key surgical approaches (sternotomy vs
thoracotomy) and the critical importance of phrenic nerve preservation
Postoperative monitoring for tamponade and right heart failure are vital.
Clinical Pearls:
Differentiation between constrictive pericarditis and restrictive cardiomyopathy is crucial pre-operatively
Cardiac catheterization provides definitive hemodynamic data
In severe calcification, a "shell-out" technique may be necessary
Recognize that complete decompression requires aggressive pericardial resection.
Common Mistakes:
Inadequate pericardial resection, leading to recurrent constriction
Injury to coronary arteries or myocardium during dissection
Failure to identify and protect phrenic nerves
Inappropriate fluid management post-operatively leading to either hypotension or pulmonary edema.