Secondary tumours – the majority

These are all malignant since they have metastasized or invaded locally. They are more common than generally realized, occurring in about 10% of all fatal malignancies. The most common primary site is lung (30% of cases of cardiac secondaries – the close proximity plays a role with direct extension to involve the pericardium and heart). Other common primary tumours metastasizing to the heart include breast, kidney, liver, melanoma (this is disproportionately numerous in relation to its total incidence), lymphoma and leukaemia.

Primary tumours – rare

Benign – e.g. myxoma, lipoma, fibroma, rhabdomyoma, papillary fibroelastoma, angioma, paraganglioma, pericardial tumours (pericardial cysts and teratomas).

Malignant – mainly sarcomas – e.g. angiosarcoma (commonest), rhabdomyosarcoma, fibrosarcoma and liposarcoma.

Echo cannot differentiate between benign and malignant tumours. 2-D echo shows tumours as echogenic masses within the cavity of the heart, attached to the wall or in the pericardium. The size and mobility can be determined. As with all echo studies, multiple views should be obtained. Occasionally on M-mode, a tumour such as myxoma may be seen interfering with valve function (section 2.1). The effects of tumours (e.g. obstruction of valve flow, LV dysfunction due to infiltration or obstruction or pericardial effusion) can also be seen on echo (Fig. 6.1).

Fig. 6.1 (a) Leiomyosarcoma (arrow) of the inferior vena cava extending into the right atrium. (b) The mass prolapses through the tricuspid valve. TOE 4-chamber view.

Myxoma

Myxomas are rare and occur in the atria or ventricles. They are gelatinous and friable (bits can break away and embolize).

Although benign in the neoplastic sense, they are far from benign in their effects. They are slow growing over years and, if untreated, usually fatal.

The effects of myxomas relate to:

Myxomas usually present in one of four ways, in decreasing order of frequency:

Myxomas may be readily detected by M-mode or 2-D echo (Fig. 6.2). The myxoma can be seen as a mass in the LA cavity and may prolapse through the MV into the LV cavity during diastole obstructing flow. It may be so large as to fill the LA. Doppler can show the haemodynamic effects.

Fig. 6.2 (a) Left atrial myxoma (arrow) shown on TOE 4-chamber view. The tumour is large and lobulated with a broad base attaching it to the interatrial septum. It can be seen to prolapse through the mitral valve. (b) It is producing a marked space-occupying effect and causing restriction of flow within the left atrium.

Myxomas very rarely occur in an autosomal dominant familial fashion associated with lentiginosis (multiple freckles) or HCM and so it is wise to screen all first-degree relatives by echo (section 7.6).

Pericardial cysts

These are the most common primary pericardial tumours and are often detected in middle age as an incidental finding during chest X-ray or echo performed for another indication. They can occur anywhere in the pericardium and are masses with echo-free centres attached to the pericardium and with intact walls separating them from the LV cavity. They are benign.

Infective endocarditis

Infection may occur on normal native valves, on previously diseased valves (e.g. rheumatic valves or calcified, degenerative valves) or on artificial (prosthetic) valves.

Endocarditis is a serious condition and potentially life-threatening. It can be acute (e.g. with Staphylococcus aureus) or subacute bacterial (SBE). Infection usually follows an episode of bacteraemia, which may not be readily identifiable, or may follow dental treatment or surgery. For this reason it is safest to advise antibiotic prophylaxis treatment for all dental treatment and all surgical procedures for individuals with a known cardiac murmur, congenital lesion, heart valve abnormality or artificial valve. Certain infecting organisms are associated with underlying disease conditions, e.g. Streptococcus bovis endocarditis with carcinoma of the colon.

Remember that endocarditis is a clinical diagnosis made on the basis of clinical history and examination, blood tests suggesting inflammation and immune complex phenomena and, if possible, culture of the organism from blood. The absence of vegetations on an echo does not exclude the diagnosis of endocarditis suspected on clinical grounds. Endocarditis may be present even in the absence of a murmur or fever, especially if antibiotics have been given.

Clinical features supporting endocarditis

Important investigations in endocarditis

Fig. 6.4 Endocarditis of the aortic valve showing a large vegetation (arrow).

Cardiac lesions predisposing to endocarditis

Uses of echo in endocarditis

• Aid diagnosis

• Detect predisposing lesions

• Search for complications

• Response to treatment

• Timing surgical intervention if necessary.

Remember that many vegetations are not seen on TTE until they are >2 mm in size. Colour Doppler may identify AR or MR, acquired VSD or a septal abscess. TOE is very useful in endocarditis, particularly for:

• Visualizing small vegetations

• MV

• Prosthetic valve endocarditis

• Leaflet perforation

• Aortic root abscess

• Sinus of Valsalva aneurysm

• LVOT aneurysm

Only gold members can continue reading. Log In or Register to continue

Share this:

• Click to share on Twitter (Opens in new window)
• Click to share on Facebook (Opens in new window)

Related

Related posts:

1. Doppler – velocities and pressures
2. Valves
3. Transoesophageal and stress echo and other echo techniques
4. Heart failure, myocardium and pericardium

Stay updated, free articles. Join our Telegram channel

Join