A Rare Case of Calcified Constrictive Pericarditis Operated Successfully

Introduction

Constrictive pericarditis (CP) is a chronic inflammatory disorder of the pericardium, the membrane surrounding the heart, characterized by fibrosis, scarring, and calcification. This stiffens the pericardium, causing diastolic dysfunction, ultimately leading to decreased cardiac output and heart failure. The most common causes of CP in the Western world are idiopathic pericarditis, surgery, and radiotherapy. In developing countries and immuno-compromised patients, tuberculosis remains the primary cause. The definitive treatment for CP is complete pericardie-ctomy, a surgical procedure that removes the constricting pericardium. Although cases of constrictive pericarditis have decreased due to early diagnosis and treatment of pericardial effusion, calcified pericardial constriction poses unique challenges during surgery.

This article presents the case of a 55-year-old male who underwent successful surgery for calcified pericardial constriction at our department.

Case Presentation

The patient, a 55-year-old male, presented with symptoms of fatigue, exertional dyspnea, abdominal heaviness, and foot edema for over a year. Despite ongoing diuretic treatment, he continued to experience swelling in both legs. Upon physical examination, the patient had a pulse rate of 105 beats per minute and blood pressure of 100/80 mmHg. He displayed pitting edema in both feet and legs, and his liver was enlarged by 2.5 cm. Additional signs included mild abdominal distension, mild ascites, and elevated jugular venous pressure with prominent y descent.

His electrocardiogram (ECG) revealed low-voltage R waves, while echocardiography indicated constrictive pericarditis, with a 6 mm thick, calcified pericardium surrounding the cardiac chambers and great vessels. The patient's left ventricular ejection fraction (LVEF) was 50%, and his inferior vena cava (IVC) was dilated and non-collapsing upon inspiration. Coronary angiography was normal, but his bloodwork revealed reduced albumin to globulin ratio (0.87), elevated serum bilirubin (2.15 mg/dl), and an increased international normalized ratio (INR) of 1.79.

Given the diagnosis of calcified pericardial constriction, the patient was advised to undergo a pericardiectomy for surgical relief.

Surgical Procedure

The patient underwent a planned pericardiectomy under general anesthesia. Invasive hemodynamic monitoring was set up, showing an initial central venous pressure (CVP) of 16 mmHg. The pericardium was accessed through a median sternotomy. In cases of pericardial constriction, challenges arise in separating the constricting layers from the epicardial surface of the heart. Complications such as hypotension, arrhythmias, inadvertent injury to cardiac chambers, coronary vessels, or phrenic nerve, and incomplete release of constriction are anticipated.

Upon opening the sternum, the entire heart was found encased in a hard, calcified layer resembling an "egg-shell" (Image 1). The main surgical challenge was breaching this calcified layer without injuring the underlying heart. Initial attempts to create an opening by tapping the pericardial surface with a steel instrument failed. Eventually, a combi-nation of a knife and heavy scissors was used to cut through the calcified pericardium, creating a small opening over the anterior surface of the right ventricle. This allowed for careful identification of the underlying epicardial surface, which began to bulge through the opening.

The incision was gradually extended towards the left ventricle and over other cardiac structures, including the right atrium, vena cava, aorta, and pulmonary artery. Dissection was meticulously performed using electro-cautery and harmonic scalpels to minimize bleeding and ensure safety. The calcified pericardium was removed piece by piece, revealing 25 ml of dark hemorrhagic fluid on the posterior side of the heart, which was sent for pathological examination.

During the surgery, the patient experienced two episodes of supraventricular tachycardia, successfully treated with direct current (DC) shock. Fortunately, no significant injuries occurred, and the operation proceeded on a beating heart. By the end of the procedure, the patient’s CVP had decreased to 8 mmHg, and his arterial blood pressure was stable at 126/70 mmHg.

Postoperative Results

Given the chronic nature of calcific constrictive pericarditis, there is a risk of postoperative myocardial dysfunction and low cardiac output due to potential myocardial fibrosis. To mitigate these risks, the patient was closely monitored in the surgical ICU.

Remarkably, the patient was extubated just two hours post-surgery and transferred from the ICU to a regular ward by the third postoperative day. His recovery was smooth, without any complications, and he was discharged on the sixth postoperative day.

A pre-discharge echocardiogram showed no evidence of pericardial constriction, and his LVEF had improved to 55%, with normal right ventricular function. Although the IVC remained dilated, its functionality was preserved. Pathological tests of the excised pericardium showed mild chronic inflammation without granulomas or acid-fast bacilli. Tests on the pericardial fluid revealed high protein content (7.38 g/dl), elevated white cell count (1400 cells/μl), and a predominance of lymphocytes (65%).

Discussion and Conclusion

Constrictive pericarditis has become a rare condition, with fewer cases requiring surgery. However, in cases of established pericardial constriction, surgery remains the only definitive treatment. Over the years, the causes of CP have shifted, particularly in developed countries. A 1999 study from the Mayo Clinic highlighted the shift from tuberculosis to post-radiation etiologies of CP, with a reported mortality rate of 6%. This trend is also being observed in developing nations.

Pericardial calcification results from prolonged inflammation, fibrosis, and necrosis. Common causes include viral infections, chest radiation, and prior cardiac surgery. Historically, tuberculosis was a significant cause of CP, but today, many cases of pericardial calcification are idiopathic. Other causes include uremic pericarditis, trauma, malignancies, and connective tissue diseases. Although asbestos exposure has been linked to pericardial calcification, more than 50% of cases remain idiopathic.

In this case, laboratory tests indicated chronic, non-tuberculous inflammation. While patchy calcification of the pericardium is not uncommon, complete calcification, as seen in this case, is rare and complicates surgical procedures. Nevertheless, with careful dissection and patience, the pericardiectomy was successfully completed using standard surgical instruments.

This case underscores the importance of surgical intervention in cases of calcific constrictive pericarditis, as well as the potential for excellent outcomes, even in cases where the pericardium is entirely calcified. With careful planning and execution, patients with CP can achieve full recovery and improved quality of life post-surgery.

References

1. Constrictive pericarditis: prevention and treatment, Dr. Mamotabo R. Matshela, European Society of Cardiology, e-Journal of Cardiology Practice, Volume 15 N° 24 - 06 Dec 2017.

2. Constrictive Pericarditis in the Modern Era - Evolving Clinical Spectrum and Impact on Outcome after Pericardiectomy, Lieng H. Ling et al, Circulation, Vol 100, Number 13, 28 Sept., 1999.

3. Pericardial Calcification, Nauman Khalid et al, NCBI Bookshelf, StatPearls, May 22, 2023.