Objective: Our goal was to demonstrate the usefulness of echocardiography and cardiac Doppler echocardiography (echo-Doppler) in the diagnosis of endomyocardial fibrosis, an unusual restrictive cardiomyopathy in Argentina.
Methods: Between 1980 and 1998, we studied 10 women (aged 27 to 58 years) with endomyocardial fibrosis confirmed by surgery and/or endomyocardial biopsy. Of the 10 cases of endomyocardial fibrothrombosis, 8 were biventricular and 2 were left ventricular. Six patients had only an echocardiographic study, and the last 4 patients (after 1987) had an echo-Doppler study also; 3 had a transesophageal echocardiography examination as well. Seven patients had grade III-IV dyspnea, 2 had an edematous-ascitic syndrome, and 1 had right heart failure at the first examination. Four patients died of heart failure and 1 of overimposed sepsis. Surgery was successful in 2 patients with the biventricular form of the disease. In one of them, fibrotic decortication was performed in both ventricles together with tricuspid and mitral replacement. In the other, the right side was not surgically treated because of its mild engagement. One patient was lost to follow-up, and 3 patients are awaiting surgery at this writing.
Results: In all 10 patients, echocardiography was the first diagnostic tool used. In M-mode echocardiography, the typical image showed the "square root" sign in the septum and posterior wall in addition to the "merlon" sign, characterized by a hypercontractile basal ventricle opposing an obliterated apex. In 2-dimensional echocardiography, inversion of the normal sized heart with obliterated ventricles and dilated atria were seen in the whole group. In 1 patient, the fibrous thrombus was limited to the apex of the right ventricle (Shaper's type 1) in a biventricular form, whereas in the left side of this patient and in the other 9 patients, the fibrous thrombus that initially occupied the apex engaged the posterior papillary muscle, pulling the posterior valve downward (Shaper's type 2) and generating tricuspid and/or mitral regurgitation that was always mild or moderate. The fibrous thrombus never altered the movement of the underlying myocardium. There were hypoechoic and hyperdense echoes inside the fibrotic material (the latter compatible with calcium), and in all 10 patients, different grades of pericardial effusion were found. Echo-Doppler showed the same minimal percentage of change in mitral and tricuspid velocities as found in healthy patients, which clearly differentiates endomyocardial fibrosis from constrictive pericarditis. Furthermore, a restrictive pattern was observed on both atrioventricular valves when both sides were engaged with a markedly short tricuspid deceleration time. Pulmonary veins showed a markedly diastolic D wave and a broad reversal A wave (the latter presented a low velocity when the wall of the left atrium was diseased) caused by an increased end-diastolic left ventricular pressure to the same extent throughout the respiratory cycle. Hepatic veins showed a markedly deep diastolic forward wave throughout the respiratory cycle and a marked reversal with inspiration.
Conclusions: We showed (1) echocardiographic studies of a significant number of patients with this unusual disease, (2) the characteristic diagnostic signs in M-mode and 2-dimensional echocardiography, and (3) the common echo-Doppler patterns shared by all subjects studied with this technique.