Dr. Nishimura’s approach to the work-up of patients with unexplained right heart failure and a normal ejection begins with the history and physical examination. The history in a patient with constrictive pericarditis is classically one of radiation therapy years earlier for a malignancy, or prior CABG surgery. And the physical exam has to reveal the presence of high neck veins.
“If you don’t see high neck veins due to elevated jugular venous pressure with rapid x and y descents, the patient doesn’t have constrictive pericarditis, no matter what the echocardiogram shows,” Dr. Nishimura asserted.
If those findings are present, however, then on 2-D echocardiography he’s looking for three things that point to constrictive pericarditis: a brisk septal shudder due to rapid filling in early diastole with every heart beat; an early diastolic posterior motion of the intraventricular septum, known as the septal bounce, that occurs as a consequence of the less compliant ventricular walls; and dilation of the inferior vena cava indicative of increased right atrial pressure.
When all three findings are present on 2-D echo, he turns to Doppler echo for hemodynamic information. If Doppler shows a reduction in transmitral driving pressure from the lungs to the heart during inspiration, as the intrathoracic pressure drops but the left ventricular pressure does not, the work-up is done. That patient has constrictive pericarditis and needs to be referred to surgery for pericardiectomy, which will bring rapid improvement.
In roughly one-quarter of patients with constrictive pericarditis, however, that full constellation of 2-D and Doppler echocardiographic findings isn’t present. It then becomes necessary to move on to cardiac catheterization. The first two things to look for in the cath lab are elevated end-equalization of diastolic pressures and low cardiac output.
“If they’re in the cath lab and they’ve got normal filling pressures and a normal cardiac output, they do not have clinically significant constrictive pericarditis, no matter what the echo shows. So those two things are necessary to see, but of course they’re not diagnostic. So we go further,” Dr. Nishimura said.