A patient with constrictive pericarditis will have enhanced ventricular interaction arising from the restraint imposed by a rigid, diseased pericardium. That’s crucial. This increased ventricular interaction is manifest as an increase in the size of the right ventricle during inspiration while the area of the left ventricle is getting smaller.
In contrast, during inspiration and expiration in a patient with restrictive cardiomyopathy, as the right ventricle gets smaller, so does the left ventricle.
“The ratio of the right ventricle to left ventricle area under the curve during inspiration versus expiration gives a very nice distinction between constrictive pericarditis and restrictive cardiomyopathy. Enhanced ventricular interaction is the most sensitive and specific finding for constrictive pericarditis,” according to Dr. Nishimura.
He added that, in addition to constrictive pericarditis and restrictive cardiomyopathy, there is a third and underappreciated cause of right heart failure with a normal ejection fraction: severe tricuspid regurgitation. This abnormality may not be readily apparent upon echocardiography in a patient with a pacemaker lead or automatic implantable cardioverter-defibrillator lead, which can cause acoustic shadowing that results in underestimation of the severity of tricuspid regurgitation. The clue here is the observation of hepatic vein systolic flow reversal, which can only be caused by severe tricuspid regurgitation.
“Think tricuspid regurgitation in patients who have a pacemaker lead or AICD, and also in older women with longstanding atrial fibrillation who dilate their tricuspid annulus and develop more and more tricuspid regurgitation. Take those patients to the cath lab and do a right ventriculogram, which will show tricuspid regurgitation,” Dr. Nishimura advised.
He reported having no financial conflicts.