Cardiac hemangiomas represent only 1 ~ 2% of all benign heart tumors. Most affected patients are asymptomatic and the symptoms depends on the tumor’s location and size, which are always non-specific, such as dyspnea, arrhythmias, angina, signs of right heart failure and thromboembolic events[4, 5]. Consequently, cardiac hemangiomas are often discovered incidentally by transthoracic echocardiography and misdiagnosed as other cardiac neoplasms(e.g. cardiac myxoma). Right ventricular hemangiomas are extremely rare, especially that at the apex of the RV. According to Jiang’s summary, the most common site of right ventricular hemangiomas is the anterior wall of the RV, but only 6.7% are located at the apex of the RV. In our case, the hemangioma is located at the apex of the RV and it grows outward reaching to 4.0cm, different from most cardiac hemangiomas which are single, relatively small subendocardial nodules(2.0 ~ 3.5cm). These characteristics make it very unusual and significantly increase the difficulty of diagnosis.
Currently, the diagnostic tools for cardiac tumors mainly include echocardiography, chest computed tomography (CT) and cardiac magnetic resonance (CMR) imaging. Transthoracic echocardiography has been the preferred diagnostic tool for cardiac tumors because of its non-invasiveness and convenience, however, it cannot distinguish the tissue level very accurately. Besides, it cannot display the blood supply of the tumor unless contrast-enhanced ultrasound is applied. Considering that there was no obvious blood flow signal in the mass on echocardiography, so we were apt to deem it was non-cardiac origin preoperatively. Contrast-enhanced CT may make up for these shortcomings, but it is unfriendly to patients who are allergy to contrast agents or with renal insufficiency. Coronary CTA and coronary angiography are also used for showing the distribution of vessels, feeding vessels to the tumor and whether the coronary arteries are oppressed. In our case, the origin of the tumor remained a mystery in result of two coronary CTA images associated with key information of the origin revealing quite different findings, leaving us in a diagnostic dilemma. If we used CMR at that time, we might be able to figure out the property of the tumor and its precise relationship with the RV anterior free wall and the pericardium. The excellent contrast resolution and multiplanar capability of CMR imaging allows qualitative diagnosis and optimal anatomical evaluation of any cardiac tumor. In addition, CMR imaging enabled us to demonstrate the precise relationship among the tumor, tricuspid valve, and RV anterior free wall, which was useful for pre-surgical planning. However, the implantation of pacemakers or metal objects such as biliary stent, and the high price limit the application of CMR in our country.
With regard to treatment, surgical removal is the first choice of therapy for cardiac hemangiomas. After a complete resection, the prognosis is generally favorable with a low recurrence rate. Even an incomplete resection is reported to produce long-term survival benefits.