Ryszard Pacho

Clinical Investigations: Pulmonary VasculatureNoninvasive Diagnosis of Suspected Severe Pulmonary Embolism: Transesophageal Echocardiography vs Spiral CT

OBJECTIVE Patients with pulmonary embolism (PE) and echocardiographic signs of right ventricular overload have worse prognosis and may require aggressive therapy. Unequivocal confirmation of PE is required before thrombolysis or embolectomy. This study compares the value of transesophageal echocardiography (TEE) and spiral CT (sCT) in direct visualization of pulmonary artery thromboemboli in patients with suspected PE and echocardiographic signs of right ventricular overload. MATERIAL AND METHODS Forty-nine consecutive patients (29 men and 20 women), aged 52.2+/-18.3 years, with clinical suspicion of acute (23) or chronic (26) PE and otherwise unexplained right ventricular overload at transthoracic echocardiography underwent TEE and sCT. Main and lobar (central) pulmonary arteries were searched for emboli with both TEE and sCT, while segmental and subsegmental (distal) pulmonary arteries were searched only with sCT. RESULTS Of 40 patients with PE confirmed by high-probability lung scan (27) or angiography (13), central pulmonary arterial emboli were found at TEE and sCT in 32 (80%) and 36 (90%) patients, respectively. Neither method reported false central PE (specificity, 100%). When distal pulmonary arteries were analyzed, sensitivity of sCT increased to 97.5%, but three patients with primary pulmonary hypertension according to standard tests were misclassified as having distal PE (specificity, 90.1%). Most patients had bilateral PE according to sCT (34/36) and standard tests (40/40) but not TEE (15/32), probably due to its topographic limitations. CONCLUSIONS Because of high prevalence of bilateral central pulmonary thromboemboli in patients with hemodynamically significant PE, both sCT and TEE allow its definitive confirmation in most cases. Thrombi reported by sCT distally to lobar arteries should be interpreted with caution.

Vascular complications after liver transplantation

Vascular complications following liver transplantation is reviewed based upon literature data and our own results. Our study conclusions are mostly based on literature data, because our center does not have the liver transplantation experience of other centers worldwide. Thus, we may conclude, that the number and character of complications does not differ from those reported by other centers. The enbloc technique used in liver harvesting minimizes the risk of arterial damage in case of vascular anomalies. Recipient retransplantation is the most effective treatment method in cases of hepatic arterial occlusion. Doppler ultrasound examinations are effective to monitor vascular blood flow in the transplanted liver.

1000 liver transplantations at the Department of General, Transplant and Liver Surgery, Medical University of Warsaw--analysis of indications and results.

THE AIM OF THE STUDY was to analyze indications and results of the first one thousand liver transplantations at Chair and Clinic of General, Transplantation and Liver Surgery, Medical University of Warsaw. MATERIAL AND METHODS Data from 1000 transplantations (944 patients) performed at Chair and Clinic of General, Transplantation and Liver Surgery between 1994 and 2011 were analyzed retrospectively. These included 943 first transplantations and 55 retransplantations and 2 re-retransplantations. Frequency of particular indications for first transplantation and retransplantations was established. Perioperative mortality was defined as death within 30 days after the transplantation. Kaplan-Meier survival analysis was used to estimate 5-year patient and graft survival. RESULTS The most common indications for first transplantation included: liver failure caused by hepatitis C infection (27.8%) and hepatitis B infection (18%) and alcoholic liver disease (17.7%). Early (< 6 months) and late (> 6 months) retransplantations were dominated by hepatic artery thrombosis (54.3%) and recurrence of the underlying disease (45%). Perioperative mortality rate was 8.9% for first transplantations and 34.5% for retransplantations. Five-year patient and graft survival rate was 74.3% and 71%, respectively, after first transplantations and 54.7% and 52.9%, respectively, after retransplantations. CONCLUSIONS Development of liver transplantation program provided more than 1000 transplantations and excellent long-term results. Liver failure caused by hepatitis C and B infections remains the most common cause of liver transplantation and structure of other indications is consistent with European data.

MR Imaging of Pulmonary Nodules: Detection Rate and Accuracy of Size Estimation in Comparison to Computed Tomography.

Objective The aims of this study were to assess the sensitivity of various magnetic resonance imaging (MRI) sequences for the diagnosis of pulmonary nodules and to estimate the accuracy of MRI for the measurement of lesion size, as compared to computed tomography (CT). Methods Fifty patients with 113 pulmonary nodules diagnosed by CT underwent lung MRI and CT. MRI studies were performed on 1.5T scanner using the following sequences: T2-TSE, T2-SPIR, T2-STIR, T2-HASTE, T1-VIBE, and T1-out-of-phase. CT and MRI data were analyzed independently by two radiologists. Results The overall sensitivity of MRI for the detection of pulmonary nodules was 80.5% and according to nodule size: 57.1% for nodules ≤4mm, 75% for nodules >4-6mm, 87.5% for nodules >6-8mm and 100% for nodules >8mm. MRI sequences yielded following sensitivities: 69% (T1-VIBE), 54.9% (T2-SPIR), 48.7% (T2-TSE), 48.7% (T1-out-of-phase), 45.1% (T2-STIR), 25.7% (T2-HASTE), respectively. There was very strong agreement between the maximum diameter of pulmonary nodules measured by CT and MRI (mean difference -0.02 mm; 95% CI –1.6–1.57 mm; Bland-Altman analysis). Conclusions MRI yielded high sensitivity for the detection of pulmonary nodules and enabled accurate assessment of their diameter. Therefore it may be considered an alternative to CT for follow-up of some lung lesions. However, due to significant number of false positive diagnoses, it is not ready to replace CT as a tool for lung nodule detection.

Outcomes Following Liver Transplantation for Metastatic Neuroendocrine Tumors

INTRODUCTION Metastatic disease is generally considered as an absolute contraindication for liver transplantation. However, due to relatively low aggressiveness and slow progression rates, liver metastases from neuroendocrine tumors (NETs) form an exception to this rule. Given the scarcity of available data, the purpose of this study was to evaluate long-term outcomes following liver transplantation for NET metastases. MATERIAL AND METHODS There were 12 primary liver transplantations in patients with NET metastases out of 1334 liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw) in the period between December 1989 and October 2013. Overall survival (OS) and disease-free survival (DFS) were set as primary and secondary outcome measures, respectively. RESULTS Median follow-up was 7.9 years. For all patients, OS rate was 78.6% at 10 years and DFS rate was 15.5% at 9 years. Intraoperative transfusions of packed red blood cells (P = .021), Ki-67 proliferative index more than 2% (P = .048), and grade 2 tumors (P = .037) were identified as factors significantly associated with worse DFS. Notably, loss of E-cadherin expression (P = .444), mitotic rate (P = .771), extent of liver involvement (P = .548), primary tumor site (P = .983), and recipient age (P = .425) were not significantly associated with DFS. CONCLUSIONS Excellent long-term OS rates support liver transplantation for unresectable NET metastases despite almost universal post-transplantation tumor recurrence. Selection of patients with G1 tumors with Ki-67 index not exceeding 2% and reducing the requirement for intraoperative blood transfusions might improve DFS rates.

Angiomyolipoma of the liver: analysis of typical features and pitfalls based on own experience and literature

We present imaging findings (ultrasound, computed tomography, and magnetic resonance imaging) of eight patients with hepatic angiomyolipoma (HAML). The lesions were solitary in seven patients, and one patient had multiple tumors (n=11). Angiomyolipoma, even though a rare liver tumor, should be included in the differential diagnosis in cases of highly vascularized lesion containing a significant amount of fat. Suggestion of the diagnosis of HAML might be helpful for the pathologist in the selection of the typical histochemical staining of the tumor, allowing accurate diagnosis, which, in turn, determines the implementation of appropriate therapeutic intervention.

Evolution Of The Results Of 1500 Liver Transplantations Performed In The Department Of General, Transplant And Liver Surgery Medical University Of Warsaw.

UNLABELLED Liver transplantation is a well-established treatment of patients with end-stage liver disease and selected liver tumors. Remarkable progress has been made over the last years concerning nearly all of its aspects. The aim of this study was to evaluate the evolution of long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw). MATERIAL AND METHODS Data of 1500 liver transplantations performed between 1989 and 2014 were retrospectively analyzed. Transplantations were divided into 3 groups: group 1 including first 500 operations, group 2 including subsequent 500, and group 3 comprising the most recent 500. Five year overall and graft survival were set as outcome measures. RESULTS Increased number of transplantations performed at the site was associated with increased age of the recipients (p<0.001) and donors (p<0.001), increased rate of male recipients (p<0.001), and increased rate of piggyback operations (p<0.001), and decreased MELD (p<0.001), as well as decreased blood (p=0.006) and plasma (p<0.001) transfusions. Overall survival was 71.6% at 5 years in group 1, 74.5% at 5 years in group 2, and 85% at 2.9 years in group 3 (p=0.008). Improvement of overall survival was particularly observed for primary transplantations (p=0.004). Increased graft survival rates did not reach the level of significance (p=0.136). CONCLUSIONS Long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery are comparable to those achieved in the largest transplant centers worldwide and are continuously improving despite increasing recipient age and wider utilization of organs procured from older donors.

Simplified method of dynamic contrast-enhanced computed tomography in the evaluation of indeterminate pulmonary nodules.

Background: Dynamic contrast-enhanced computed tomography (CECT) is one of the methods used in the evaluation of lung nodules. Objectives: The aim of the study was to evaluate the accuracy of the simplified method (based on only 2 postcontrast measurements) of dynamic CECT in determining the nature of pulmonary nodules. Methods: Forty nodules (solid, 10–40 mm in diameter, spherical, with no visible calcification or fatty tissue) in 40 patients were analyzed. In 30 patients, the nature of the nodule was confirmed by pathological examination. In 10 cases, the nodules were assumed to be benign, as no growth within 2 years was radiologically documented. All patients underwent CECT according to a simplified protocol (based on pre-enhancement and 2 postcontrast measurements at 30 s and 4 min after contrast injection). Results: Twenty-three (57.5%) nodules were proved to be malignant and 17 (42.5%) benign. The 7 benign and none of the malignant nodules showed an enhancement value of ≤15 Hounsfield units. Thus, the sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of shortened dynamic CECT were 100, 41, 70, 100 and 75%, respectively. Conclusions: In CECT, contrast enhancement of a pulmonary nodule ≤15 Hounsfield units is a reliable predictor of its benignity. Reduction in the number of postcontrast measurements in the simplified method of dynamic CECT does not influence its sensitivity.

The impact of experience of a transplantation center on the outcomes of orthotopic liver transplantation

The so-called learning factor has been disregarded for many years in analyzing the causes of surgical complications and post-operative mortality; it is also the case for OLT. In our center until April 2003, 209 OLT were performed in 196 patients. We evaluated the impact of experience of the transplantation team on the outcomes of liver transplantation. Thirty-four patients died (mortality rate, 16%) and 1-year survival rate, 64%. Mortality rates varied during different periods of observation due to increasing experience of the transplantation team. The causes of mortality were assessed for a series of 34 patients: it was 75% at the beginning of transplantation procedures while recent deaths have not recently exceeded 10% of cases.

Usefulness of 16-Row Multidetector Computed Tomography With Volume Rendering and Maximum Intensity Projection Reconstruction as a Monitor Pancreatic Graft Vessel Patency During the Early Postoperative Period

Thrombosis of the pancreatic graft vessels is the most common complication after transplantation. It leads to loss of 5% to 8% of grafts during the early postoperative period. The aims of this study were to evaluate the usefulness of 16-row multidetector computed tomography (16-MDCT) with volume rendering (VR) and maximum intensity projection (MIP) reconstruction to monitor pancreatic graft vessel patency during the early postoperative period and the efficacy of a heparin infusion as a treatment for graft thrombosis. Among 40 consecutive simultaneous pancreas-kidney transplant recipients, 16-MDCT was performed at 6 to 8 days after the operation. Secondary reconstructions were obtained with VR and MIP algorithms to evaluate the morphology and patency of the extra- and intrapancreatic arteries and veins. In cases of thrombosis, every patient was treated with an infusion of unfractionated heparin. In 15 recipients, thrombosis of the large vessels was detected by 16-MDCT. Heparin infusions saved five pancreatic grafts (5/15; 33.3%), but the other 10 pancreatic grafts were removed. In another four recipients (4/40; 10%) the thrombi were localized only in small intrapancreatic vessels. Treatment with heparin infusion was successful in 3/4 (75%) cases with patent vessels upon control computed tomography examination. We compared the efficacy of heparin treatment depending on the diameter of the thrombosed vessel, observing a significant difference (5/15 vs 3/4; P < .01; chi-square). 16-MDCT with secondary reconstruction by application of VR and MIP algorithms was an efficient method to visualize not only large pancreatic graft arteries and veins but also intrapancreatic parenchymal vessels. In cases of thrombosis of small intrapancreatic vessels, unfractionated heparin infusion significantly decreased graft loss.