Intramyocardial Dissecting Hematoma
A26-year-old man was admitted to a private nursing home in December 1995 with the sudden onset of palpitations. He was diagnosed as having ventricular tachycardia (monomorphic, left-axis −60°; rate, 210 bpm) with pronounced hemodynamic instability. He was electrically cardioverted to sinus rhythm. Clinical examination revealed a normal heart with no obvious structural heart disease and no metabolic precipitants. Because he had repeated episodes of ventricular tachycardia, he was started on 1000 mg/d amiodarone, which was tapered to 400 mg/d by the end of 1 week. Echocardiographic results were normal. The patient remained asymptomatic until February 1996, when he had a similar episode of palpitations. At this stage, he was referred to us for further management.
Physical examination was normal except for cardiomegaly, which was confirmed on chest roentgenography. Echocardiography revealed a uniformly echogenic mass of 8.5×8 cm in relation to the right ventricle (Fig 1A⇓), which was visualized as a crescentic cavity. The proximal right coronary artery was dilated; the remainder of the chambers were normal. A repeat echocardiogram after 7 days showed mixed echogenicity in the mass (Fig 1B⇓). A diagnosis of pericardial hematoma was considered. Magnetic resonance imaging of the heart was performed to confirm the diagnosis, but the scan indicated the presence of an intracardiac mass (Fig 1C⇓). Cardiac catheterization was performed to determine the relation of the coronary vessels to the mass and to assess the right coronary artery; it revealed a dilated proximal right coronary artery with an abrupt termination, with the branches spread over a mass (Fig 2A⇓) and a negative shadow of the mass compressing the right ventricle (Fig 2B⇓). At this stage, a diagnosis of intramyocardial hematoma was made. During this period, the patient had multiple episodes of ventricular tachycardia, which were terminated with overdrive pacing.
The patient underwent surgery on a semiemergent basis; cardiopulmonary bypass was available. A median sternotomy was performed. The pericardium was normal, and a diffuse mass that measured 10×9.5×8 cm was seen in relation to the right ventricle (Fig 3A⇓). Aortic and right atrial purse-string sutures were made, and an additional purse-string suture was made over the mass. Needle aspiration was performed, which revealed altered blood suggestive, by appearance only, of a resolving hematoma. A 2-cm stab incision was made within the purse-string suture, and 680 g of blood clots was evacuated. This incision was extended further laterally. On careful inspection, the intramyocardial nature of the hematoma was confirmed (Fig 3B⇓), and the source of bleeding was identified in the region corresponding to the abrupt termination of the right coronary artery; the bleeding source was closed with a polypropylene suture. Double breasting of the redundant ventricular wall was performed. There was improvement in hemodynamic parameters after evacuation of the hematoma. The patient made an uneventful recovery. He has not had further recurrences of ventricular arrhythmias while on a maintenance dosage of 200 mg/d amiodarone. Postoperative echocardiography showed no recurrence of the hematoma and revealed good right ventricular function, which was also seen on postoperative cardiac catheterization (Fig 4⇓). The right coronary artery remains dilated.
Although intramyocardial hematoma is very rare, it has been described as a complication of myocardial infarction.1 The hematoma may progress along naturally occurring dissection planes between the ventricular spiral muscles, where it is described as an “intramyocardial dissecting hematoma.”2 Such a complication has not been described to have a spontaneous occurrence. In our patient, the dilated proximal right coronary artery suggests that a long-standing high-flow situation (probably a coronary arteriovenous fistula) was the antecedent pathology, which with a catastrophic event such as a rupture gave rise to the intramyocardial hematoma.
The editor of Images in Cardiovascular Medicine is Hugh A. McAllister, Jr, MD, Chief, Department of Pathology, St Luke’s Episcopal Hospital and Texas Heart Institute, and Clinical Professor of Pathology, University of Texas Medical School and Baylor College of Medicine.
Circulation encourages readers to submit cardiovascular images to Dr Hugh A. McAllister, Jr, St Luke’s Episcopal Hospital and Texas Heart Institute, 6720 Bertner Ave, MC 1–267, Houston, TX 77030.
- Copyright © 1998 by American Heart Association