Excision of innumerable hydatid cysts from the myocardium of the left ventricle via the left thoracotomy along with myoplasty on beating heart

Abstract

Cardiac hydatid cyst is a rare disease with frequency of less than 2%. The left ventricle is the most common site. Symptoms depend upon site of involvement ranging from asymptomatic to acute coronary syndrome, arrhythmias, valvular lesions, etc. It is a surgical emergency, therefore early diagnosis and surgical treatment is required even in asymptomatic patients. Surgical excision on beating heart along with preparedness with cardiopulmonary bypass and fibrillator via left anterolateral thoracotomy can be done successfully, followed by medical treatment with albendazole. Increased awareness and high degree of suspicion among cardiac physicians in the endemic area is essential for early diagnosis. Echocardiography remains the gold standard for diagnosis and follow-up of patient.

Introduction

Hydatid disease is a disease of temperate climate caused by Echinococcus granulosus, E.multilocularis, or E.vogeli [1, 2]. It is endemic in the areas where man, sheep, and dog come in close contact. Common sites of infestation are the liver, lung, brain, spleen, kidney, bone, muscle, pelvis, heart, spinal cord, and retina. Cardiac involvement occurs in lesser than 2% of the cases [3, 4]. The left ventricle is the most common site of cardiac involvement [1].

Surgery is treatment of choice for cardiac hydatid cyst. Rapid diagnosis must be obtained using various imaging modalities with early surgical and pharmacological treatment of suspicious cystic masses, especially in endemic areas [1].

We report successful surgical treatment in a case of hydatid cyst of left ventricular wall through left antero-lateral thoracotomy approach [5, 6].

Case report

A 23-year-old man presented with history of dull aching left-sided chest pain, palpitations, and breathlessness (NYHA class II) for the past 6 months. His heart rate was 108 per minute and regular and blood pressure was 130/80 mmHg. On auscultation, the heart sounds were normal and there was no added sound or murmur. Chest and abdominal clinical examination was unremarkable. There was no history of seizures. Complete blood count was normal with eosinophil count of 01%. Serum enzyme-linked immune sorbent assay (ELISA) for Echinococcus was positive. Chest X-ray showed cardiomegaly with lobulated swelling over left cardiac silhouette. Electrocardiogram (ECG) revealed T wave inversion in leads I, II, aVL, and V4-V6. Transthoracic echocardiography demonstrated well-defined cystic lesion of approximate size of 5.0 × 7.0 cm (multi-loculated with daughter cysts) attached to postero-lateral wall of the left ventricle, with normal chamber size, normal valve echo, without any regional wall motion abnormality (RWMA), and the left ventricular ejection fraction (LVEF) 55%. The cardiac computed tomography (CT) revealed well-defined cystic lesion of 6.0 × 7.5 cm size with multiple loculations in relation to postero-lateral and inferior wall of the left ventricle, containing numerous daughter cysts of variable sizes ranging from 0.5 to 3 cm. There was no intra-cavitary extension or involvement of coronaries and lung parenchyma [Fig. 1]. Ultrasound abdomen was also unremarkable.

Fig. 1.

Chest X-ray showing lobulated left cardiac silhoute, echocardiography with multiple cysts, CT scan showing left ventricular myocardial hydatid cyst with normal coronaries

Based on the above investigations, diagnosis of the left ventricular hydatid cyst was made and surgical excision was planned on beating heart via left antero-lateral thoracotomy through fifth intercostal space, keeping provision for establishment of cardiopulmonary bypass and the fibrillator ready. Transesophageal echocardiography (TEE) is used to assess the intra-cavitary extension of hydatid cyst peroperatively.

The left anterolateral thoracotomy was done through fifth intercostal space. Peroperatively, lobulated cystic mass was seen extending over the lateral, posterior and inferior walls of the left ventricle. As soon as a linear incision was made over the cyst wall, multiple cysts started delivering spontaneously with each heartbeat. After evacuating all the cysts, pericardial cavity was washed thoroughly with 10% povidone iodine solution. Large cystic cavity was found to be extending medially into myocardium. Pericyst was excised and the left ventricle muscle was sutured to restore the normal trapezoid geometry of the left ventricle (myoplasty) (Fig. 2).

Fig. 2.

Innumerable cysts with spontaneous delivery assisted by each heartbeat, cavity after evacuation of cysts, normal trapezoid geometry of the left ventricle after myoplasty

Postoperative period remained uneventful with just 6 h of ICU stay to keep a watch over the vital parameters. Chest drain was removed on the first postoperative day and the patient was discharged on the fifth postoperative day; albendazole (400 mg once daily) therapy was started from the first postoperative day with advice to continue it for 12 weeks. Histopathology report also confirmed the diagnosis of hydatid cyst.

Discussion

Cardiac echinococcosis is a rare disease. The frequency of cardiac involvement is less than 2% of the cases. The left ventricular invasion occurs in 55–60% due to huge myocardial mass and blood supply. The incidence of involvement of the interventricular septum is 5–9%, right ventricle 15%, right atrium 3–4% and pulmonary artery, left atrium, and pericardium up to 7–8% [3, 6].

Routes of transmission of larvae are the coronary circulation, intestinal lymphatic vessels, thoracic duct, vena cavae and the hemorrhoidal veins of large intestine and pulmonary veins [7, 8].

Signs and symptoms depend upon the site and size of the cyst. Ten percent of the patients remain asymptomatic. As the size increases, it may cause chest pain, breathlessness, and obstruction in outflow tract [7]. Also, the invasion of the conductive system of the heart may cause cardiac arrhythmias, atrioventricular nodal blocks, ventricular tachycardia and fibrillation, cardiac tamponade, and acute coronary syndrome [1, 2, 7, 8]. Pulmonary embolism, anaphylactic shock, and systemic metastasis are the worst complications of cardiac hydatid cysts [1, 2, 9].

Differential diagnoses include intracardiac tumors, congenital cysts, and aneurysm [1].

Transthoracic echocardiography is the gold standard in detecting cardiac hydatidosis, as it is noninvasive, can be easily performed, and is highly sensitive in detecting intracardiac lesions [1, 2, 10]. Serologic tests are helpful too, but false negative results are common. Coronary angiography (CAG) is also required [1]. TEE is an indispensable tool for intraoperative evaluation of cyst number, size, and location in relation to cardiac chambers. TEE is also used peroperatively to detect any residual cyst.

Cardiac CT is a useful diagnostic tool to help in diagnosis and defining the extent of the disease. Also, delineation of coronary anatomy, lung parenchyma, and pericardial cavity can be done simultaneously.

The management of hydatid cyst is based on the size, location, presentation, and health of the patient. Percutaneous aspiration, infusion of scolicidal agent and reaspiration (PAIR) procedure has not been tried in cardiac hydatid cysts. Surgical excision is the definitive treatment [1, 2]. Literature review shows median sternotomy with cardiopulmonary bypass as the most common approach [1–4, 7, 9, 10]. Minimal invasive approach to avoid median sternotomy with cardiac pulmonary bypass (CPB) can be used in selected cases, where hydatid cysts are superficial and not extending to the left ventricle cavity. In our case, left thoracotomy [5, 6] approach was used on beating heart, avoiding the complications and morbidity [8] related to median sternotomy and cardiopulmonary bypass. Both on-pump and off-pump approaches have been advised [2, 8]. Even off-pump hydatid cyst excision from myocardium can be done successfully, especially in myocardial hydatid cyst with no intracavitary extension, keeping the cardiopulmonary bypass, and fibrillator ready. Anaphylaxis and dissemination of infected scolices are known complications. Hydatid cyst should be sterilized before enucleation by instillation of 2% formalin, 0.5% silver nitrate solution, 20% hypertonic saline solution, 10% iodine solution, or 5% cetrimonium bromide solution. Precaution should be taken for toxic substances like formalin and absolute alcohol, as they can enter the systemic circulation and can be disastrous [2, 7]. We injected 20% hypertonic saline solution, followed by irrigation of the cyst and pericardial cavity by 10% povidone iodine solution [2]. Patient was discharged without any complications. Transthoracic echocardiography (TTE) is advisable to assess the recurrence at interval of every 6 months regularly [7, 10].

Conclusion

High index of suspicion is required to clinch the diagnosis in endemic areas. Surgery should not be delayed even in asymptomatic patients, and minimal invasive approach on beating heart is feasible.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical considerations

Ethical issues (including plagiarism, informed consent, misconduct, data fabrication and/or falsification, double publication and/or submission, redundancy, etc.) have been completely observed by the authors. Informed consent was obtained from all individual participant included in the study. All procedures performed in study involving human participants were in accordance with the ethical standards of the institutional research committee and is applicable according to Schedule-Y, Indian Council of Medical Research (ICMR) Guidelines for Biomedical research on Human Subjects-2006, ICH-GCP guidelines which govern Good Clinical Practices and IEC/IRB operations, Declaration of Helsinki (Seoul, 2008), and 21 Code of Federal Regulations (CFR) part 56 and 21 CFR part 50.