Distal aortic biomechanics after transcatheter versus surgical aortic valve replacement: a hypothesis generating study.

BACKGROUND: Biomechanical effects of transcatheter (TAVR) versus surgical (SAVR) aortic valve interventions on the distal aorta have not been studied. This study utilized global circumferential strain (GCS) to assess post-procedural biomechanics changes in the descending aorta after TAVR versus SAVR. METHODS: Patients undergoing TAVR or SAVR for aortic stenosis were included. Transesophageal (TEE) and transthoracic (TTE) echocardiography short-axis images of the aorta were used to image the descending aorta immediately before and after interventions. Image analysis was performed with two-dimensional speckle tracking echocardiography and dedicated software. Delta GCS was calculated as: post-procedural GCS-pre-procedural GCS. Percentage delta GCS was calculated as: (delta GCS/pre-procedural GCS) × 100. RESULTS: Eighty patients, 40 TAVR (median age 81 y/o, 40% female) and 40 SAVR (median 72 y/o, 30% female) were included. The post-procedure GCS was significantly higher than the pre-procedural GCS in the TAVR (median 10.7 [interquartile range IQR 4.5, 14.6] vs. 17.0 [IQR 6.1, 20.9], p = 0.009) but not in the SAVR group (4.4 [IQR 3.3, 5.3] vs. 4.7 [IQR 3.9, 5.6], p = 0.3). The delta GCS and the percentage delta GCS were both significantly higher in the TAVR versus SAVR group (2.8% [IQR 1.4, 6] vs. 0.15% [IQR - 0.6, 1.5], p < 0.001; and 28.8% [IQR 14.6%, 64.6%] vs. 4.4% [IQR - 10.6%, 5.6%], p = 0.006). Results were consistent after multivariable adjustment for key clinical and hemodynamic characteristics. CONCLUSIONS: After TAVR, there was a significantly larger increase in GCS in the distal aorta compared to SAVR. This may impact descending aortic remodeling and long-term risk of aortic events.

Indirect ballistic injury to the liver resulting in retained bullet complicated with hepatic abscess: a case report.

Indirect and extraperitoneal penetrating liver injury is an extremely uncommon phenomenon. In this report, we highlight the case of an 18-year-old male patient that sustained a gunshot wound with an entry site through the right buttock and landed in the liver. He presented to us in sepsis due to developing a hepatic abscess at the site of the dislodged bullet that was confirmed with computed tomography. Interestingly, the ballistic missile did not cause any visceral injury due to its indirect and extraperitoneal trajectory. The patient underwent diagnostic laparoscopy, where the hepatic abscess was unroofed and evacuated. A free-floating bullet was found and extracted, and a small bile duct leak was repaired. The patient had an uneventful post-operative course and was duly discharged on an empiric course of antibiotics.

Management of ruptured hepatocellular carcinoma invading the gastrointestinal tract: A case report.

INTRODUCTION AND IMPORTANCE: Hepatocellular carcinoma (HCC) constitutes most of primary liver cancers. HCC invading the gastrointestinal tract (GIT) is considered a rare entity with limited reports in the literature. Management can either be palliative or curative such as transarterial chemoembolization (TACE) followed by definitive resection. Here, we present a case of direct HCC invasion of the GIT that was managed by surgical resection. CASE PRESENTATION: A 74-year-old male with a history of a liver mass, found to have HCC. Admitted for medical optimization prior to definitive resection, however his stay was complicated by hemorrhagic shock, with imaging findings of hemoperitoneum suggestive of spontaneous rupture of the mass. TACE was done to stabilize the patient prior to resection. Patient was taken immediately to the operating room for definitive resection. CLINICAL DISCUSSION: Most cases of direct HCC invasion into the GI tract present mainly with GI bleed. Some patients, present with abdominal pain without any warning signs of an occult GI bleed. Thus, absence of an occult GI bleeding does not exclude a GIT invasion. Management options are several, but in advanced stages, management is not limited to palliation. CONCLUSION: GIT invasion is a rare complication of HCC reported in scarcity in the literature. Most cases present with GI bleeding but with some rare cases, they present with more generalized symptoms like abdominal pain, weight loss or fatigue. Despite having a poor prognosis, complete surgical resection of the tumor may be a reassuring and life prolonging treatment option for these patients.

Metastatic melanoma to the small bowel causing intussusception: A case report.

INTRODUCTION AND IMPORTANCE: Melanoma is a malignant skin neoplasm with a high metastatic potential. Several reports have shown that metastatic melanoma has a predilection to metastasize to the GI tract; however, diagnosing metastatic melanoma as a cause of intussusception has been reported in only few cases with variable presentations. CASE PRESENTATION: We present the case of a 48-year-old woman with a long history of metastatic melanoma who presented with recurrent enteric intussusception due to a melanoma lesion acting as a pathologic lead point despite immunotherapy treatment. We contribute the management plan, diagnostic modalities, and surgical approach of this rare form of adult intussusception in guidance of future management plans. CLINICAL DISCUSSION: The variability in presentation of adult intussusception makes diagnosis difficult and the lack of consensus on management and surgical strategies poses challenging hurdles. A diagnostic laparoscopy followed by reduction and resection of the intussuscepted lesion in a small surgical field is an effective and beneficial palliative procedure with favorable outcomes. Our patient developed intussusception despite receiving a trial of dual immunotherapy after chemotherapy. CONCLUSION: It may be insufficient to control disease even with dual immunotherapy after chemotherapy. Further studies are needed to determine the optimal surgical and oncological management in treating gastrointestinal metastasis of malignant melanoma.

Initiating a Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy Program Based on a Single Center Experience in Lebanon.

PURPOSE: In 2018, the American University of Beirut Medical Center established the first multidisciplinary Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy program in Lebanon. The study describes the challenges faced in establishing the program and in improving patient referral, evaluation, and perioperative care. METHODS: The program establishment including the preparation phase, clinical evaluation, and team education is discussed. The implementation of the flow of patients referred to the program was established. Education regarding diagnosis and referral were provided to physicians in the community. The initial experience is described in a retrospective analysis of 4 consecutive patients who were diagnosed with CTEPH and underwent PEA. RESULTS: Four patients were diagnosed with CTEPH had PEA performed. The mean age of patients was 64 years. The average CPB and total circulatory arrest times were 244 and 23.9 minutes per side, respectively. No mortalities were encountered perio-operatively. All patients reported significant improvement in functional capacity from NYHA III and IV to a NYHA class of I with an average PASP decrease of 59.5 ± 19.7 mmHg and mPAP drop by 30.2 ± 16.3 mmHg. CONCLUSION: The launch of the first CTEPH and PEA program in Lebanon, with a clear framework, coupled with good surgical outcomes is very encouraging. The program offers a curative solution for CTEPH patients in the region. A clear referral process and an increase in disease and treatment awareness in the community are crucial to the future success of the program, offering a definitive treatment, and avoiding delays to surgery.

Management of a mechanical aortic valve during left ventricular assist device implantation in a previously replaced aortic root.

The use of left ventricular assist device (LVAD) in patients with mechanical aortic valves may result in thromboembolic events due to blood stasis around the valve and intermittent valve opening. Mechanical aortic valves encountered during LVAD implantation are managed by replacement with a tissue valve, or closure of the valve with a patch. Closure of the valve carries the risk of sudden death in cases of LVAD stoppage. Replacing the whole mechanical valve conduit is time consuming and carries a significant risk of bleeding and right ventricular (RV) failure. We describe an alternative technique of replacing a mechanical aortic valve by breaking its inner leaflets and sewing a tissue valve on top of the mechanical valve ring.

Chk1 and DNA-PK mediate TPEN-induced DNA damage in a ROS dependent manner in human colon cancer cells.

Recently, we showed that the metal chelator TPEN targets colon cancer cells through redox cycling of copper. Here, we studied the DNA damage potential of TPEN and deciphered the role of Chk1, ATM and DNA-PK in TPEN-induced toxicity in 3 human colon cancer cell lines, HCT116, SW480 and HT29. We also investigated the role of reactive oxygen species (ROS) in TPEN-induced DNA damage. TPEN reduced cell viability in a dose- and time-dependent manner. Cytotoxicity was associated with significant DNA damage and higher expression of γ-H2AX protein and activation of ATM/ATR signaling pathway. Cell death by TPEN was dependent on ROS generation as evidenced by the reversal of cell viability, and DNA damage and the abrogation of γ-H2AX levels in the presence of antioxidants. Treatment with antioxidants, however, failed to reverse cytotoxicity at high TPEN concentrations (10µM). TPEN-induced cell death was also dependent on the redox cycling of copper since the copper chelator neocuproine inhibited DNA damage and reduced pChk1, γ-H2AX, and ATM protein expression. Cell death by low TPEN concentrations, involved ATM/ATR signaling in all 3 cell lines, since pre-incubation with specific inhibitors of ATM and DNA-PK led to the recovery of cells from TPEN-induced DNA damage. In addition, siRNA silencing of Chk1, DNA-PK and ATM abrogated the expression of γ-H2AX and reversed cell death, suggesting that Chk1 and DNA-PK mediate TPEN-induced cytotoxicity in colon cancer cells. This study shows for the first time the involvement of Chk1, DNA-PK and ATM in TPEN-induced DNA damage and confirms our previous findings that ROS generation and the redox cycling of copper in response to TPEN are the main mechanisms by which this compound induces cell death in human colon cancer cells. Inhibition of ATM or DNA-PK did not reverse cytotoxicity at high TPEN concentrations that cause excessive levels of ROS and irreversible cellular damage.