Abnormal portal vein waveform as an indicator of constrictive pericarditis - a case report.

We report a case of a 17-year-old patient referred to our outpatient Doppler Department due to clinical suspicion of liver cirrhosis. The patient presented with non-specific symptoms, such as malaise, pain in the right subcostal region, peripheral oedema. Until then, diagnostic imaging, including echocardiography was inconclusive. We performed the Doppler sonography of the portal system, which revealed normal diameter of the portal vein with abnormal, phasic and markedly pulsatile waveform. Hepatic veins distention with pathological reverse flow during systole was reported. Additionally, inferior vena cava was dilated and remained unchanged through the respiratory cycle. Basing on the above image a heart disease, which had not been taken into differential diagnosis before, was suggested. The following echocardiography, together with computed tomography, enabled a diagnosis of constrictive pericarditis. Successful pericardiotomy was performed. Such a complicated diagnostics happened to demonstrate an uncommon example of the use of portal vein waveform in making the proper cardiologic diagnosis.

We report a case of a 17-year-old patient referred from the municipal hospital to our outpatient Doppler Department with the suspicion of liver cirrhosis. The patient suffered from malaise, pain in the right subcostal region and peripheral oedema. Until then, diagnostic procedures, including echocardiography, had not been conclusive and the diagnosis had not been made.

Doppler ultrasound of the portal system revealed a normal diameter portal vein with an abnormal, phasic and pulsatile waveform during the initial phase of inspiration (Fig. 1). Waveforms from the distended hepatic veins were also abnormal, yet with mild, reversed flow in diastole, which is a feature of tricuspid insufficiency (Fig. 2 and 3). Additionally, the inferior vena cava was dilated and stiffened during the respiratory cycle.

Fig. 1

Abnormal, phasic and pulsatile waveform from the portal vein

Fig. 2

Distension of hepatic veins

Fig. 3

Triphasic waveforms from hepatic veins showing reversed flow in diastole

On the grounds of these two anomalies a cardiac pathology was suspected. Features of constrictive pericarditis were observed in the succeeding echocardiography. This diagnosis was confirmed by computed tomography. A successful pericardiotomy was performed.

Discussion

Doppler ultrasound of the portal system has been used for over 20 years. Being highly accessible and facilitating simultaneous Doppler signal and B-mode image, ultrasonography enabled an unique, non-invasive, imaging method of the portal system. The primary studies on this technique investigated blood flow in the portal veins and its tributaries quantitatively. Using this data, some researchers attempted to evaluate the stage of portal hypertension. Special attention was paid in quest for prognostic features of the most severe complication of the portal hypertension, i.e. esophageal varices bleeding.

Quantitative measurement of the portal system flow was abandoned due to being technically demanding, of poor repeatability, and not fulfilling the awaited assumptions. It was replaced by the qualitative study, which examined only the shape and direction of portal vein waveform. The normal portal vein waveform is antegrade (towards the liver), and shows a mild undulation depending on the cardiac cycle and respiratory variation. It was believed that flat, irrespective of the heart cycle portal vein waveform is suggestive of portal hypertension. However, clinical practice has shown that this easily detected on the routine examination abnormality is present only in 56% of patients with portal hypertension. Moreover, this feature of portal vein waveform is proved not to be a reliable indicator of the liver damage extent (no correlation with the Child-Pugh score)(.

It seems that portal vein waveform evaluation has preserved its established diagnostic value merely in assessing the direction of the blood flow [towards the liver (hepatopetal) vs directed away from the liver (hepatofugal)], and additionally in the diagnostic imaging of portal vein thrombosis and its complications.

In contrast to these unfavorable reports, our case of constrictive pericarditis has introduced a spectacular diagnostic value of portal vein waveform pathology, which eventually led to the diagnostic success.

Waveform from the portal vein was analysed in cardiology patients. The Authors presented pathologic, phasic and pulsatile waveform from the portal vein in the groups presenting with the right heart failure, tricuspid insufficiency, constrictive pericarditis, diffuse iatrogenic mediastinal haematoma and in patients after porto-systemic shunt surgery(.

It should be emphasised that evident, pulsatile portal waveform without retrograde flow can be encountered also in health, especially in thin individuals(.

The above presented case report endorses the use of ‘peripheral’ portal system sign, i.e. deformed, pulsatile portal vein waveform, in making a correct cardiologic diagnosis.