Mohamad H. El Zein
Johns Hopkins University
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Featured researches published by Mohamad H. El Zein.
Gastrointestinal Endoscopy | 2015
Mouen A. Khashab; Ahmed A. Messallam; Manabu Onimaru; Ezra N. Teitelbaum; Michael B. Ujiki; Matthew E. Gitelis; Rani J. Modayil; Eric S. Hungness; Stavros N. Stavropoulos; Mohamad H. El Zein; Hironari Shiwaku; Rastislav Kunda; Alessandro Repici; Hitomi Minami; Philip W. Chiu; Jeffrey L. Ponsky; Vivek Kumbhari; Payal Saxena; Amit Maydeo; Haruhiro Inoue
BACKGROUND Limited data exist on the use of peroral endoscopic myotomy (POEM) for therapy of spastic esophageal disorders (SEDs). OBJECTIVE To study the efficacy and safety of POEM for the treatment of patients with diffuse esophageal spasm, jackhammer esophagus, or type III (spastic) achalasia. DESIGN Retrospective study. SETTING International, multicenter, academic institutions. PATIENTS All patients who underwent POEM for treatment of SEDs refractory to medical therapy at 11 centers were included. INTERVENTIONS POEM. MAIN OUTCOME MEASUREMENTS Eckardt score and adverse events. RESULTS A total of 73 patients underwent POEM for treatment of SEDs (diffuse esophageal spasm 9, jackhammer esophagus 10, spastic achalasia 54). POEM was successfully completed in all patients, with a mean procedural time of 118 minutes. The mean length of the submucosal tunnel was 19 cm, and the mean myotomy length was 16 cm. A total of 8 adverse events (11%) occurred, with 5 rated as mild, 3 moderate, and 0 severe. The mean length of hospital stay was 3.4 days. There was a significant decrease in Eckardt scores after POEM (6.71 vs 1.13; P = .0001). Overall, clinical response was observed in 93% of patients during a mean follow-up of 234 days. Chest pain significantly improved in 87% of patients who reported chest pain before POEM. Repeat manometry after POEM was available in 44 patients and showed resolution of initial manometric abnormalities in all cases. LIMITATIONS Retrospective design and selection bias. CONCLUSION POEM offers a logical therapeutic modality for patients with SEDs refractory to medical therapy. Results from this international study suggest POEM as an effective and safe platform for these patients.
Gastrointestinal Endoscopy | 2015
Mouen A. Khashab; Vivek Kumbhari; Ian S. Grimm; Saowanee Ngamruengphong; Gerard Aguila; Mohamad H. El Zein; Anthony N. Kalloo; Todd H. Baron
BACKGROUND AND AIMS There are limitations to enteral self-expandable metal stents and surgical gastrojejunostomy in the treatment of patients with gastric outlet obstruction (GOO). EUS-guided gastroenterostomy (EUS-GE) is a novel procedure that potentially offers long-lasting luminal patency without the risk of tumor ingrowth and/or overgrowth, while avoiding the morbidity of a surgical procedure. The aims of this study were to report the first U.S. clinical experience with EUS-GE in terms of technical success, clinical success, and adverse events and to detail the technical aspects of performing EUS-GE. METHODS This was a retrospective study from two tertiary-care centers. EUS-GE was performed by using either the direct EUS-GE or balloon-assisted EUS-GE technique. Technical success was defined as adequate positioning and deployment of the stent as determined endoscopically and radiologically. Clinical success was defined as the patients ability to tolerate oral intake without vomiting. RESULTS A total of 10 patients underwent attempted EUS-GE. Malignant GOO was present in 3 patients, whereas benign obstruction was found in the remaining 7. One patient had complete GOO and underwent successful direct EUS-GE. In the remaining 9 patients, balloon-assisted EUS-GE was attempted and was successful in 8. Thus, technical success occurred in 9 patients (90%). There were no procedure-related adverse events. Mean procedure time was 96 minutes (range 45-152 minutes), and mean length of hospital stay was 2.2 days. Clinical success with resumption of solid oral intake was achieved in all 9 patients (100%) who underwent successful EUS-GE. A total of 8 patients were able to tolerate almost a normal diet and/or full diet, and 1 patient tolerated a soft diet. There was no symptom recurrence during a mean follow-up period of 150 days. CONCLUSIONS EUS-GE is a promising new technique for the treatment of symptoms of benign and malignant GOO. Prospective, multicenter trials are needed to confirm these results.
Gastrointestinal Endoscopy | 2015
Mouen A. Khashab; Sepideh Besharati; Saowanee Ngamruengphong; Vivek Kumbhari; Mohamad H. El Zein; Ellen M. Stein; Alan Tieu; Gerard E. Mullin; Sameer Dhalla; Monica Nandwani; Vikesh K. Singh; Marcia I. Canto; Anthony N. Kalloo; John O. Clarke
BACKGROUND AND AIMS Medical treatment options for gastroparesis are limited. Data from studies of botulinum toxin and surgical pyloroplasty suggest that disruption of the pylorus can result in symptomatic improvement in some patients with refractory gastroparetic symptoms. The aim of this study was to determine the clinical response to transpyloric stent (TPS) placement in patients with gastroparetic symptoms refractory to standard therapy. METHODS Patients with gastroparesis refractory to medical treatment were referred for TPS placement for salvage therapy. Self-reported symptom improvement, stent migration rate, and pre- and post-stent gastric-emptying study results were collected. RESULTS A total of 30 patients with refractory gastroparesis underwent 48 TPS procedures. Of these, 25 of 48 (52.1%) were performed in patients admitted to the hospital with intractable gastroparetic symptoms. Successful stent placement in the desired location across the pylorus (technical success) was achieved during 47 procedures (98%). Most (n = 24) stents were anchored to the gastric wall by using endoscopic suturing with a mean number of sutures of 2 (range 1-3) per procedure. Clinical response was observed in 75% of patients, and all inpatients were successfully discharged. Clinical success in patients with the predominant symptoms of nausea and vomiting was higher than in those patients with a predominant symptom of pain (79% vs 21%, P = .12). A repeat gastric-emptying study was performed in 16 patients, and the mean 4-hour gastric emptying normalized in 6 patients and significantly improved in 5 patients. Stent migration was least common (48%) when stents were sutured. CONCLUSION TPS placement is a feasible novel endoscopic treatment modality for gastroparesis and improves both symptoms and gastric emptying in patients who are refractory to medical treatment, especially those with nausea and vomiting. TPS placement may be considered as salvage therapy for inpatients with intractable symptoms or potentially as a method to select patients who may respond to more permanent therapies directed at the pylorus.
Gastrointestinal Endoscopy | 2016
Dennis Yang; Sunil Amin; Susana Gonzalez; Stephen Hasak; Srinivas Gaddam; Steven A. Edmundowicz; Mark A. Gromski; John M. DeWitt; Mohamad H. El Zein; Mouen A. Khashab; Andrew Y. Wang; Jonathan P. Gaspar; Dushant S. Uppal; Satish Nagula; Samir Kapadia; Jonathan M. Buscaglia; Juan Carlos Bucobo; Alexander Schlachterman; Mihir S. Wagh; Peter V. Draganov; Min Kyu Jung; Tyler Stevens; John J. Vargo; Harshit S. Khara; Mustafa Huseini; David L. Diehl; Ryan Law; Srinadh Komanduri; Patrick Yachimski; Tomas DaVee
BACKGROUND AND AIMS The need for transpapillary drainage (TPD) in patients undergoing transmural drainage (TMD) of pancreatic fluid collections (PFCs) remains unclear. The aims of this study were to compare treatment outcomes between patients with pancreatic pseudocysts undergoing TMD versus combined (TMD and TPD) drainage (CD) and to identify predictors of symptomatic and radiologic resolution. METHODS This is a retrospective review of 375 consecutive patients with PFCs who underwent EUS-guided TMD from 2008 to 2014 at 15 academic centers in the United States. Main outcome measures included TMD and CD technical success, treatment outcomes (symptomatic and radiologic resolution) at follow-up, and predictors of treatment outcomes on logistic regression. RESULTS A total of 375 patients underwent EUS-guided TMD of PFCs, of which 174 were pseudocysts. TMD alone was performed in 95 (55%) and CD in 79 (45%) pseudocysts. Technical success was as follows: TMD, 92 (97%) versus CD, 35 (44%) (P = .0001). There was no difference in adverse events between the TMD (15%) and CD (14%) cohorts (P = .23). Median long-term (LT) follow-up after transmural stent removal was 324 days (interquartile range, 72-493 days) for TMD and 201 days (interquartile range, 150-493 days) (P = .37). There was no difference in LT symptomatic resolution (TMD, 69% vs CD, 62%; P = .61) or LT radiologic resolution (TMD, 71% vs CD, 67%; P = .79). TPD attempt was negatively associated with LT radiologic resolution of pseudocyst (odds ratio, 0.11; 95% confidence interval, 0.02-0.8; P = .03). CONCLUSIONS TPD has no benefit on treatment outcomes in patients undergoing EUS-guided TMD of pancreatic pseudocysts and negatively affects LT resolution of PFCs.
Endoscopy International Open | 2016
Mouen A. Khashab; Schalk Van der Merwe; Rastislav Kunda; Mohamad H. El Zein; Anthony Y. Teoh; Fernando P. Marson; Carlo Fabbri; Ilaria Tarantino; Shyam Varadarajulu; Rani J. Modayil; Stavros N. Stavropoulos; I Peñas; Saowanee Ngamruengphong; Vivek Kumbhari; Joseph Romagnuolo; Raj J. Shah; Anthony N. Kalloo; Manuel Perez-Miranda; Everson L. Artifon
Background and aims: Endoscopic ultrasound-guided biliary drainage (EUS-BD) has emerged as an alternative to traditional radiologic and surgical drainage procedures after failed endoscopic retrograde cholangiopancreatography (ERCP). However, prospective multicenter data are lacking. The aims of this study were to prospectively assess the short- and long-term efficacy and safety of EUS-BD in patients with malignant distal biliary obstruction. Patients and methods: Consecutive patients at 12 tertiary centers (5 US, 5 European, 1 Asian, 1 South American) with malignant distal biliary obstruction and failed ERCP underwent EUS-BD. Technical success was defined as successful stent placement in the desired position. Clinical success was defined as a reduction in bilirubin by 50 % at 2 weeks or to below 3 mg/dL at 4 weeks. Adverse events were prospectively tracked and graded according to the American Society for Gastrointestinal Endoscopy (ASGE) lexicon’s severity grading system. Overall survival and duration of stent patency were calculated using Kaplan–Meier analysis. Results: A total of 96 patients (mean age 66 years, female 45 %, pancreatic cancer 55 %) underwent EUS-BD. Stent placement (technical success) was achieved in 92 (95.8 %) patients (metallic stent 84, plastic stent 8). Mean procedure time was 40 minutes. Clinical success was achieved in 86 (89.5 %) patients. A total of 10 (10.5 %) adverse events occurred: pneumoperitoneum (n = 2), sheared wire (n = 1), bleeding (n = 1), bile leak (n = 3), cholangitis (n = 2), and unintentional perforation (n = 1); 4 graded as mild, 4 moderate, 1 severe, and 1 fatal (due to perforation). A total of 38 (44 %) patients died of disease progression during the study period. The median patient survival was 167 days (95 %CI 112 – 221) days. The 6-month stent patency rate was 95 % (95 %CI 94.94 – 95.06 %) and the 1-year stent patency was 86 % (95 %CI 85.74 – 86.26 %). Conclusion: This study on EUS-BD demonstrates excellent efficacy and safety of EUS-BD when performed by experts. Study registration: NCT01889953
Endoscopy | 2017
Vivek Kumbhari; Pietro Familiari; Niels Christian Bjerregaard; Mathieu Pioche; Edward L. Jones; Weon Jin Ko; Bu Hayee; Anna Cali; Saowanee Ngamruengphong; François Mion; Ruben Hernaez; Sabine Roman; Alan H. Tieu; Mohamad H. El Zein; Tokunbo Ajayi; Amyn Haji; Joo Young Cho; Jeffrey W. Hazey; Kyle A. Perry; Thierry Ponchon; Rastislav Kunda; Guido Costamagna; Mouen A. Khashab
Background and study aims The variables associated with gastroesophageal reflux (GER) after peroral endoscopic myotomy (POEM) are largely unknown. This study aimed to: 1) identify the prevalence of reflux esophagitis and asymptomatic GER in patients who underwent POEM, and 2) evaluate patient and intraprocedural variables associated with post-POEM GER. Patients and methods All patients who underwent POEM and subsequent objective testing for GER (pH study with or without upper gastrointestinal [GI] endoscopy) at seven tertiary academic centers (one Asian, two US, four European) were included. Patients were divided into two groups: 1) DeMeester score ≥ 14.72 (cases) and 2) DeMeester score of < 14.72 (controls). Asymptomatic GER was defined as a patient with a DeMeester score ≥ 14.72 who was not consuming proton pump inhibitor (PPI). Results A total of 282 patients (female 48.2 %, Caucasian 84.8 %; mean body mass index 24.1 kg/m2) were included. Clinical success was achieved in 94.3 % of patients. GER evaluation was completed after a median follow-up of 12 months (interquartile range 10 - 24 months). A DeMeester score of ≥ 14.72 was seen in 57.8 % of patients. Multivariable analysis revealed female sex to be the only independent association (odds ratio 1.69, 95 % confidence interval 1.04 - 2.74) with post-POEM GER. No intraprocedural variables were associated with GER. Upper GI endoscopy was available in 233 patients, 54 (23.2 %) of whom were noted to have reflux esophagitis (majority Los Angeles Grade A or B). GER was asymptomatic in 60.1 %. Conclusion Post-POEM GER was seen in the majority of patients. No intraprocedural variables were identified to allow for potential alteration in procedural technique.
Endoscopy International Open | 2016
Mouen A. Khashab; Ahmed A. Messallam; I Peñas; Yousuke Nakai; Rani J. Modayil; Carlos De la Serna; Kazuo Hara; Mohamad H. El Zein; Stavros N. Stavropoulos; Manuel Perez-Miranda; Vivek Kumbhari; Saowanee Ngamruengphong; Vinay Dhir; Do Hyun Park
Background and study aims: Endoscopic ultrasound-guided biliary drainage (EUS-BD) can be performed entirely transgastrically (hepatogastrostomy/EUS-HG) or transduodenally (choledochoduodenostomy/EUS-CDS). It is unknown how both techniques compare. The aims of this study were to compare efficacy and safety of both techniques and identify predictors of adverse events. Patients and methods: Consecutive jaundiced patients with distal malignant biliary obstruction who underwent EUS-BD at multiple international centers were included. Technical/clinical success, adverse events, stent complications, and survival were assessed. Results: A total of 121 patients underwent EUS-BD (CDS 60, HG 61). Technical success was achieved in 112 (92.56 %) patients (EUS-CDS 93.3 %, EUS-HG 91.8 %, P = 0.75). Clinical success was attained in 85.5 % of patients who underwent EUS-CDS group as compared to 82.1 % of patients who underwent EUS-HG (P = 0.64). Adverse events occurred more commonly in the EUS-HG group (19.67 % vs. 13.3 %, P = 0.37). Both plastic stenting (OR 4.95, 95 %CI 1.41 – 17.38, P = 0.01) and use of non-coaxial electrocautery (OR 3.95, 95 %CI 1.16 – 13.40, P = 0.03) were independently associated with adverse events. Length of hospital stay was significantly shorter in the CDS group (5.6 days vs. 12.7 days, P < 0.001). Mean follow-up duration was 151 ± 159 days. The 1-year stent patency probability was greater in the EUS-CDS group [0.98 (95 %CI 0.76 – 0.96) vs 0.60 (95 %CI 0.35 – 0.78)] but overall patency was not significantly different. There was no difference in median survival times between the groups (P = 0.36) Conclusions: Both EUS-CDS and EUS-HG are effective and safe techniques for the treatment of distal biliary obstruction after failed ERCP. However, CDS is associated with shorter hospital stay, improved stent patency, and fewer procedure- and stent-related complications. Metallic stents should be placed whenever feasible and non-coaxial electrocautery should be avoided when possible as plastic stenting and non-coaxial electrocautery were independently associated with occurrence of adverse events.
Endoscopy | 2016
Saowanee Ngamruengphong; Reem Z. Sharaiha; Amrita Sethi; Ali Siddiqui; Christopher J. DiMaio; Susana Gonzalez; Jennifer Im; Jason N. Rogart; Sophia Jagroop; Jessica L. Widmer; Raza Hasan; Sobia N. Laique; Tamas A. Gonda; John M. Poneros; Amit P. Desai; Amy Tyberg; Vivek Kumbhari; Mohamad H. El Zein; Ahmed Abdelgelil; Sepideh Besharati; Ruben Hernaez; Patrick I. Okolo; Vikesh K. Singh; Anthony N. Kalloo; Michel Kahaleh; Mouen A. Khashab
BACKGROUND AND STUDY AIMS Fully covered self-expandable metal stents (FCSEMSs) have increasingly been used in benign upper gastrointestinal (UGI) conditions; however, stent migration remains a major limitation. Endoscopic suture fixation (ESF) may prevent stent migration. The aims of this study were to compare the frequency of stent migration in patients who received endoscopic suturing for stent fixation (ESF group) compared with those who did not (NSF group) and to assess the impact of ESF on clinical outcome. PATIENTS AND METHODS This was a retrospective study of patients who underwent FCSEMS placement for benign UGI diseases. Patients were divided into either the NSF or ESF group. Outcome variables, including stent migration, clinical success (resolution of underlying pathology), and adverse events, were compared. RESULTS A total of 125 patients (44 in ESF group, 81 in NSF group; 56 benign strictures, 69 leaks/fistulas/perforations) underwent 224 stenting procedures. Stent migration was significantly more common in the NSF group (33 % vs. 16 %; P = 0.03). Time to stent migration was longer in the ESF group (P = 0.02). ESF appeared to protect against stent migration in patients with a history of stent migration (adjusted odds ratio [OR] 0.09; P = 0.002). ESF was also significantly associated with a higher rate of clinical success (60 % vs. 38 %; P = 0.03). Rates of adverse events were similar between the two groups. CONCLUSIONS Endoscopic suturing for stent fixation is safe and associated with a decreased migration rate, particularly in patients with a prior history of stent migration. It may also improve clinical response, likely because of the reduction in stent migration.
Endoscopy International Open | 2017
Mouen A. Khashab; Majidah Bukhari; Todd H. Baron; Jose Nieto; Mohamad H. El Zein; Yen-I. Chen; Yamile Haito Chavez; Saowanee Ngamruengphong; Ahmad S. Alawad; Vivek Kumbhari; Takao Itoi
Background and study aims EUS-guided gastroenterostomy (EUS-GE) is a novel procedure that potentially offers long-lasting luminal patency without the risk of tumor ingrowth/overgrowth. This study compared the clinical success, technical success, adverse events (AEs), length of hospital stay (LOHS) and symptom recurrence in EUS-GE versus SGJ. Methods This was a multicenter international retrospective comparative study of EUS-GE and SGJ in patients with malignant gastric outlet obstruction (GOO) who underwent either EUS-GE or SGJ. EUS-GE was performed using lumen apposing metal stents. Results A total of 93 patients with malignant GOO treated with either EUS-GE (n = 30) or SGJ (n = 63) were identified. Peritoneal carcinomatosis was present in 13 (43 %) patients in the EUS-GE group and 7 (11 %) patients in the SGJ group (P < 0.001). Although the technical success rate was significantly higher in the SGJ group as compared to the EUS-GE group (100 % vs. 87 %, P = 0.009), the clinical success rate was not different (90 % vs. 87 %, P = 0.18, OR 0.8, 95 %CI 0.44 – 7.07). The rate of AEs was lower in the EUS-GE group, but the difference was not statistically significant (16 % vs 25 %, P = 0.3). The mean LOHS was similar in the EUS-GE group compared to SGJ (P = 0.35). The rate of recurrent GOO was not different between the two groups (3 % vs. 14 %, P = 0.08). Similarly, the mean time to reintervention was similar (88 days vs. 121 days, P = 0.83). Conclusions EUS-GE is associated with equivalent efficacy and safety as compared to surgical GJ. This is the first comparative trial between both techniques and suggests EUS-GE as a non-inferior but less invasive alter to surgery.
Endoscopy International Open | 2016
Mouen A. Khashab; Mohamad H. El Zein; Kaveh Sharzehi; Fernando P. Marson; Oleh Haluszka; Aaron J. Small; Yousuke Nakai; Do Hyun Park; Rastislav Kunda; Anthony Y. Teoh; I Peñas; Manuel Perez-Miranda; Vivek Kumbhari; Schalk Van der Merwe; Everson L. Artifon; Andrew S. Ross
Background and study aims: How enteroscopy-assisted ERCP (e-ERCP) and endoscopic ultrasound-guided biliary drainage (EUS-BD) compare in patients with surgically altered upper gastrointestinal anatomy is currently unknown. The aims of this study were to compare efficacy and safety of both techniques and study predictors of these outcomes. Patients and methods: This was an international, multicenter comparative cohort study at 10 tertiary centers. Outcomes data included technical success (biliary access with cholangiography and stent placement [when indicated]), clinical success (resolution of biliary obstruction) and adverse events (AEs) (graded according to the ASGE lexicon). Results: A total of 98 patients underwent EUS-BD (n = 49) or e-ERCP (n = 49). Technical success was achieved in 48 (98 %) patients in the EUS-BD group as compared to 32 (65.3 %) patients in the e-ERCP group (OR 12.48, P = 0.001). Clinical success was attained in 88 % of patients in EUS-BD group as compared to 59.1 % in the e-ERCP group (OR 2.83, P = 0.03). Procedural time was significantly shorter in the EUS-BD group (55 min vs 95 min, P < 0.0001). AEs occurred more commonly in the EUS-BD group (20 % vs. 4 %, P = 0.01). However, the majority (90 %) of AEs were mild/moderate. Length of stay was significantly longer in the EUS-BD group (6.6 d vs. 2.4 d, P < 0.0001). Conclusions: EUS-BD can be performed with a higher degree of clinical efficacy and shorter procedure time than e-ERCP in patients with surgically-altered upper gastrointestinal anatomy. Whether or not this approach should be first-line therapy in this patient population is highly dependent on the indication for the procedure, the patient’s anatomy, and local practice and expertise.