Clinical predictors and characteristics of patients with chronic liver disease and intrapulmonary shunts

Abstract

SummaryBackground: Intrapulmonary shunting (IPS) is a well-described phenomenon in chronic liver disease but its significance is not known.Hypothesis: The study was undertaken to enhance our understanding of the characteristics and prevalence of IPS.Methods: We retrospectively studied 204 consecutive patients with end-stage chronic liver disease who underwent a dobutamine stress echocardiogram, along with a saline contrast bubble study, as part of their pretransplant evaluation.Results: Intrapulmonary shunting of any degree was present in 56.4% of patients. Patients with IPS were more likely to report alcohol use and less likely to have diabetes mellitus. Patients in Child-Pugh classification C were more likely to have IPS than those with classification A or B. The resting room air PaO2 levels were significantly lower in patients with grade 3-4 IPS than in those with grade 1-2. Elevated estimated pulmonary systolic pressure on echocardiography was more prevalent in patients with than in those without IPS.Conclusions: A majority of patients with end-stage chronic liver disease undergoing transplant evaluation have IPS. There are important baseline differences between patients with and without IPS. The presence of IPS is associated with increased severity of chronic liver disease. Further study is required to define the prognostic significance of IPS and its impact on future liver transplantation.

Portopulmonary hypertension and hepatopulmonary syndrome: a clinician-oriented overview

“…HPS has been reported in 10-30% of patients referred for LTx evaluation [60,61], but in only 1% of patients with chronic liver disease in the non-transplant setting [62]. The presence of either intrapulmonary shunts or oxygenation abnormalities are more common, occurring in 25-65% of patients awaiting LTx and in 5% of patients in the non-transplant setting [61][62][63][64]. HPS is usually diagnosed during the sixth decade of life and there is no specific association with sex or aetiology of liver disease.…”

Ocorrência de síndrome hepatopulmonar em pacientes cirróticos candidatos a transplante de fígado

“…(19) In the present study, the TTE results were suggestive of IPVD in 52% of the patients, which is in accordance with the results of other studies, in which rates ranging from 30 to 56% were reported. (4,(25)(26)(27) It is of note that, in the present study, the waiting time for transplantation was long (mean, 27 months). This is similar to that reported for other liver transplant centers before the MELD score came into use as a means of determining the position on the waiting list.…”

Hepatopulmonary syndrome: an update

“…72 However, these differences are probably due to differences in image quality, which is better when images are taken at the second harmonic frequency rather than at the fundamental frequency. 73,74 There is one report in which higher occurrence of IPVD in comparison to findings from other studies [72][73][74][75] was attributed to better resolution of the TTE images at the second harmonic. 76 The sensitivity of TTE for diagnosing IPVD is currently questioned less than its capacity to rule out false-positive results, such as cases of patent foramen ovale.…”

“…76 The sensitivity of TTE for diagnosing IPVD is currently questioned less than its capacity to rule out false-positive results, such as cases of patent foramen ovale. 69,75 TTE studies have demonstrated greater sensitivity for diagnosing patent foramen ovale when the Valsalva maneuver is used to increase the pressure in the right atrium, thereby facilitating the opening of this orifice and reducing the number of false-positive findings of IPVD. 77 Although echocardiography is better than 99m TcMAA, there may be false-positive results with the TTE technique, depending on the echocardiographic technique used.…”