Chapter 13

Endomyocardial Biopsy

Chantal El Amm, MD and Leslie T. Cooper, Jr., MD

1. Why is an endomyocardial biopsy (EMB) performed?

A few cardiovascular disorders can only or most accurately be diagnosed by examination of heart tissue. These disorders include giant cell myocarditis, amyloidosis, and allograft rejection. In each case, the unique information gained from EMB can inform prognosis and/or guide treatment. The information gained from EMB can also help diagnose certain restrictive cardiomyopathies and cardiac masses.

2. How is an EMB performed?

A bioptome is shown in Figure 13-1. The Stanford-Caves-Schultz and the King bioptomes access the right ventricle through the right internal jugular vein. A modified Cordis bioptome (B-18110, Wolfgang Meiners Medizintechnik, Monheim, Germany) has been used for access from the right femoral vein. The subclavian and left femoral veins are used less frequently.

Figure 13-1 An example of a bioptome used for endomyocardial biopsy.

The femoral artery may be used as a percutaneous access site for left ventricular biopsy.

The right ventricular septum is the preferred site for EMB, to minimize the risk of perforation. Fluoroscopy and/or echocardiography guidance are essential to localize the site of biopsy. Endocardial voltage mapping has been used to identify biopsy sites in suspected arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) and cardiac sarcoidosis. Six to eight samples are generally obtained using the Stanford-Caves device. Up to ten samples are obtained by investigators who use the smaller Meiners Medizintechnik bioptome.

The sample must be handled carefully to minimize crush artifacts. The biopsy specimen should be transferred from the bioptome to fixative by use of a sterile needle and not with forceps.

3. What are the risks associated with an EMB?

Risks correlated with EMB are summarized in Table 13-1. EMB is associated with a serious acute complication rate of less than 1% using the current flexible bioptomes, and the overall rate of complication is reported as less than 6% in most case series. Complications include access-site hematoma, transient right bundle branch block (RBBB), transient arrhythmias, tricuspid regurgitation, and, rarely, pulmonary embolism. Life-threatening complications occur far less frequently. Right ventricular perforation was reported in less than 1% of patients. Following cardiac transplant, the risk is especially low. The risks of EMB depend on the clinical state of the patient, the experience of the operator, and site procedural volume.