A fluttering papillary fibroelastoma in an atypical location: a case report

¹Department of Cardiology B, Ibn Sina Hospital, University Mohammed V of Rabat, Rabat, Morocco

^&Corresponding author
Najlaa Belharty, Department of Cardiology B, Ibn Sina Hospital, University Mohammed V of Rabat, Rabat, Morocco

Introduction    

Papillary fibroelastomas (PFEs) are rare primary, benign, cardiac tumors, that rank as the third most prevalent, following myxomas and lipomas [1,2]. While the majority of patients show no symptoms, a subset may encounter cerebral embolic manifestations like stroke or transient ischemic attack. Other potential effects encompass angina, acute coronary syndrome, and myocardial infarction secondary to obstruction of the coronary ostium in the case of aortic localization. Papillary fibroelastomas (PFEs) exhibit a propensity for the cardiac left side, affecting predominantly the aortic valve, followed by the mitral leaflets to a lesser extent [3]. We hereby report a case of echocardiography incidental discovery of a fluttering PFE that is attached to the posterior papillary muscle, presenting in an uncommon area.

Patient and observation     

Patient Information: an 86-year-old woman with a history of systemic hypertension, type 2 diabetes, and complete atrioventricular block which underwent a pacemaker implantation, presented to the emergency department for right-sided hemiparesis and aphasia.

Clinical findings: physical exam revealed normal blood pressure (120/70 mmHg) and normal heart rate (80 beats per minute), no fever (body temperature at 37°C), or systemic signs of infection.

Diagnostic assessment: upon admission, a cranial computed tomography (CT) scan was conducted, revealing the diagnosis of ischemic stroke in the middle cerebral artery territory (Figure 1). An electrocardiogram (ECG) was positive for a paced rhythm (Figure 2). The chest radiogram showed no signs of infection. As part of the etiologic evaluation, the patient was transferred to our unit for a routine echocardiogram. Transthoracic echocardiography (TTE) revealed the presence of a 10 mm isoechoic mobile mass adhering to the posteromedial papillary muscle that is fluttering into the left cardiac chamber, strongly suggesting a cardiac PFE (Figure 3, Figure 4). Her electrolyte levels and blood counts were all within the normal ranges. Three sets of blood cultures were collected and yielded no signs of bacteremia.

Therapeutic interventions and follow-up: the patient declined any further imaging for better characterization of the cardiac mass and any surgical procedure. She remained a few days in the hospital, receiving physiotherapy.

Patient perspective: the patient expressed contentment on the management of her condition.

Informed consent: we received the patient's informed consent.

Discussion     

Papillary fibroelastomas (PFEs), uncommon benign cardiac tumors, occurring at a prevalence ranging from 0.002% to 0.28%, are typically diagnosed around the age of 56, and they are more frequently reported in males (58% of cases) [2]. Macroscopically, PFEs exhibit a resemblance to a "sea anemone" with a surface covered by a gelatinous membrane and a stalk that bears numerous delicate papillary projections [3]. It predominantly affects cardiac valves, but also, although rarely, the endocardium, tendinous cords, and papillary muscles [1]. The aortic valve is affected at a percentage of 44%, the left ventricular outflow tract, and the anterior mitral leaflet (AML) at a percentage of 35%. Interestingly, cases involving the aortic valve are associated with sudden death and myocardial infarction, while systemic embolization of tumor fragments is prevalent in instances involving the mitral valve [2]. The location reported in our case was not documented in the two most comprehensive reviews published, which characterized and described 887 cases of PFE [4,5]. Transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE) are the prevailing imaging techniques employed for diagnosis. Transthoracic echocardiography (TTE) alone displays diagnostic sensitivity and specificity for PFEs, standing at 88.8% and 88.7%, respectively. However, in cases of suspected smaller PFEs (<0.2 cm), TEE exhibits higher sensitivity (76.6%) compared to TTE (61.9%). Additional modalities such as cardiac magnetic resonance imaging (MRI) are also utilized, however, MRI has been regarded as a less optimal imaging method for examining suspected PFEs cases due to their frequent small size and attachment to moving structures, leading to motion artifacts [6].

Based on published individual case reports, Sun JP and colleagues observed distinct echocardiographic traits associated with PFEs. These encompass (1) a rounded, oval, or irregular appearance with clearly defined edges and a uniform texture; (2) the majority of PFEs being of small size (99% being under 20 mm in the largest dimension); (3) about half of CPFs having stalks and demonstrating mobility; (4). Papillary fibroelastomas (PFEs) manifesting as single or multiple lesions, commonly linked to cardiac valvular conditions [4]. In our case, the diagnosis has been solely established by TTE, given the typical appearance, although the location is unconventional and might lead to confusion. Lambl´s excrescences, myxomas, thrombi, and vegetation being differential diagnoses, histopathological examination ultimately makes the precise distinction. Lambl excrescences share a comparable histopathological nature with cardiac PFEs. However, the contrast lies in the size, texture, positioning, and endothelial cell coverage. Papillary fibroelastomas are larger, possess a more gelatinous consistency, and are typically situated apart from the line of valve closure, featuring multiple layers of endothelial cells. In contrast, lambl excrescences are smaller, located precisely at the valve closure line, and possess a single endothelial layer. The growth of Lambl excrescences might be constrained due to their exposure to high stresses in their location. Conversely, fibroelastomas are commonly found in less mechanically stressed regions of valves and the endocardium. As a result, fibroelastomas tend to be bulkier and often display finger-like projections on their surfaces [7]. Surgical removal of PFEs is advised for patients displaying symptoms. However, determining the appropriate course of action for asymptomatic patients is less straightforward. Certain reports propose that the delicate structure and frond-like papillary composition of the tumor make it susceptible to thromboembolism. Consequently, immediate surgical intervention is recommended once the diagnosis is confirmed, even in cases where patients are asymptomatic. Other studies have put forth the idea that vigilant observation is a viable approach for asymptomatic patients, provided the tumor remains small and immobile [8].

Conclusion     

While PFEs are histologically classified as benign cardiac tumors, they potentially lead to life-threatening complications if they cause valve obstruction or systemic embolization, as illustrated in our patient's case. Hence, it is highly advisable to conduct meticulous echocardiographic assessments when evaluating valvular or sub-valvular masses, particularly following an embolic event.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Patient management: Najlaa Belharty and Tanae El Ghali. Data collection: Najlaa Belharty and Selma Siagh. Manuscript drafting: Najlaa Belharty. Manuscript revision: Fatima Azzahra Benmessaoud, Nawal Doghmi and Mohamed Cherti. All the authors have read and agreed to the final manuscript.

Figures     

Figure 1: a twelve leads electrocardiogram showing a paced rhythm at a ventricular rate of 60 beats per minute, no atrial fibrillation is detected

Figure 2: brain computed tomography was undergone two days after the clinical presentation, demonstrating an infarction of the left middle cerebral artery territory without haemorrhagic transformation

Figure 3: four chamber view on transthoracic echocardiography revealing the presence of an isoechoic mass (arrow) protruding into the left chamber, and the absence of masses adhering to the cardiac valves or the endocardial electrodes

Figure 4: two chambers view of transthoracic echocardiography revealing the presence and the adherence of the protrusive mass to the posterior papillary muscle (arrow)

References