Steven Phan

Transcatheter Aortic Valve Implantation (TAVI) in Patients With Bicuspid Aortic Valve Stenosis – Systematic Review and Meta-Analysis

BACKGROUND Transcatheter aortic valve implantation (TAVI) is a feasible interventional technique for severe aortic stenosis in patients who are deemed inoperable or at high surgical risk. There is limited evidence for the safety and efficacy of TAVI in patients with bicuspid aortic valves (BAV), the most common congenital valve abnormality. In many TAVI trials, patients with BAV have been contraindicated due to concerns surrounding abnormal valve geometry, leading to malfunction or malpositioning. A systematic review and meta-analysis was conducted in order to assess the current evidence and relative merits of TAVI in aortic stenosis patients with BAV. METHOD From six electronic databases, seven articles including 149 BAV and 2096 non-BAV patients undergoing TAVI were analysed. RESULTS Between the BAV and no-BAV cohorts, there was no difference in 30-day mortality (8.3% vs 9.0%; P=0.68), post-TAVI mean peak gradients (weighted mean difference, 0.36 mmHg; P=0.55), moderate or severe paravalvular leak (25.7% vs 19.9%; P=0.29), pacemaker implantations (18.5% vs 27.9%; P=0.52), life-threatening bleeding (8.2% vs 13.9%; P=0.33), major bleeding (20% vs 16.8%; P=0.88), conversion to conventional surgery (1.9% vs 1.2%; P=0.18) and vascular complications (8.6% vs 10.1%; P=0.32). CONCLUSIONS Preliminary short and mid-term pooled data from observation studies suggest that TAVI is feasible and safe in older patients with BAV. While future randomised trials are not likely, larger adequately-powered multi-institutional studies are warranted to assess the long-term durability and complications associated with TAVI in older BAV patients with severe aortic stenosis.

Thoracoscopic surgical ablation versus catheter ablation for atrial fibrillation.

For patients with atrial fibrillation (AF) who are refractory to anti-arrhythmic drugs (AADs), minimally invasive video-assisted thoracoscopic surgical ablation (SA) and catheter ablation (CA) are potential alternative treatment options. The recent FAST randomized study suggested that thoracoscopic SA was superior to CA in achieving freedom of AF in patients who have failed at least one prior AAD. To assess the relative merits and risks of SA versus CA, a systematic review and meta-analysis was conducted. Electronic searches were performed using six databases from their inception to December 2014. Relevant studies comparing thoracoscopic SA and CA were identified; data were extracted and analysed according to predefined clinical endpoints. Relative risk (RR) and weighted mean difference were used as summary statistics. Freedom from AF/arrhythmias was significantly higher in SA versus CA at 12-month off-AAD (78.4 vs 53%; RR, 1.54; P < 0.0001) and on-AAD (82.6 vs 45.7%; RR, 1.85; P < 0.00001). This difference was maintained in paroxysmal and persistent AF subgroups. The SA cohort had a significantly lower requirement for repeat ablations compared with the CA cohort (4.7 vs 24.4%; RR, 0.21; P = 0.0001). However, major complications were significantly higher in the SA group (28.2 vs 7.8%; RR, 3.30; P = 0.0003), driven by pleural effusion and pneumothorax. SA may be more efficacious than CA treatment in a selected patient population with refractory AF and prior failed catheter intervention. Improved freedom from arrhythmias at up to 12-month follow-up is counterbalanced by higher procedural complication rates.

Meta-analysis of stent-assisted coiling versus coiling-only for the treatment of intracranial aneurysms

Endovascular coil embolization is a widely accepted and useful treatment modality for intracranial aneurysms. However, the principal limitation of this technique is the high aneurysm recurrence. The adjunct use of stents for coil embolization procedures has revolutionized the field of endovascular aneurysm management, however its safety and efficacy remains unclear. Two independent reviewers searched six databases from inception to July 2015 for trials that reported outcomes according to those who received stent-assisted coiling versus coiling-only (no stent-assistance). There were 14 observational studies involving 2698 stent-assisted coiling and 29,388 coiling-only patients. The pooled immediate occlusion rate for stent-assisted coiling was 57.7% (range: 20.2%-89.2%) and 48.7% (range: 31.7%-89.2%) for coiling-only, with no significant difference between the two (odds ratio [OR}=1.01; 95% confidence intervals [CI}: 0.68-1.49). However, progressive thrombosis was significantly more likely in stent-assisted coiling (29.9%) compared to coiling-only (17.5%) (OR=2.71; 95% CI: 1.95-3.75). Aneurysm recurrence was significantly lower in stent-assisted coiling (12.7%) compared to coiling-only (27.9%) (OR=0.43; 95% CI: 0.28-0.66). In terms of complications, there was no significant difference between the two techniques for all-complications, permanent complications or thrombotic complications. Mortality was significantly higher in the stent-assisted group 1.4% (range: 0%-27.5%) compared to the coiling-only group 0.2% (range: 0%-19.7%) (OR=2.16; 95% CI: 1.33-3.52). Based on limited evidence, stent-assisted coiling shows similar immediate occlusion rates, improved progressive thrombosis and decreased aneurysm recurrence compared to coiling-only, but is associated with a higher mortality rate. Future randomized controlled trials are warranted to clarify the safety of stent-associated coiling.

Laparotomy vs minimally invasive laparoscopic ventriculoperitoneal shunt placement for hydrocephalus: A systematic review and meta-analysis

Ventriculoperitoneal shunt (VPS) surgery is the most commonly used method for the treatment of hydrocephalus. Traditionally, distal catheters in the VPS surgery have been placed either through a standard small open laparotomy or via a laparoscopic technique. Although there are many studies demonstrating the benefits of a minimally invasive approach, limited research has directly compared the two techniques used in VPS surgery. The present meta-analysis aims to provide the first comprehensive review of all published observational studies and randomized controlled trials reporting outcomes of laparotomy and laparoscopy in VPS. Electronic searches were performed using six databases from their inception to February 2015. Relevant studies comparing conventional laparotomy and a laparoscopic video-guided approach in VPS were included. Data were extracted and analyzed according to predefined clinical endpoints. A total of ten studies were identified for inclusion in the present analysis. Results indicated that the laparoscopic technique was associated with a slight but significant reduction in operating time (∼ 10 min), a significantly lower rate of abdominal malposition, distal obstruction and distal shunt failure. There was no difference between the laparotomic and laparoscopic approaches in the length of hospital stay, complication rate, proximal shunt failure or infection rate. The present systematic review and meta-analysis demonstrated that the laparoscopic technique in VPS surgery is associated with reduced shunt failure and abdominal malposition compared to the open laparotomy technique, with no significant difference in rates of infection or other complications. The lack of studies with high levels of evidence may contribute to bias in our conclusions and the long-term relative merits require validation by further prospective, randomized studies.

Reconstruction of Thoracic Spine Using a Personalized 3D-Printed Vertebral Body in Adolescent with T9 Primary Bone Tumor

BACKGROUND Neurosurgery and spine surgery have the potential to benefit from the use of 3-dimensional printing (3DP) technology due to complex anatomic considerations and the delicate nature of surrounding structures. We report a procedure that uses a 3D-printed titanium T9 vertebral body implant post T9 vertebrectomy for a primary bone tumor. CASE DESCRIPTION A 14-year-old female presented with progressive kyphoscoliosis and a pathologic fracture of the T9 vertebra with sagittal and coronal deformity due to a destructive primary bone tumor. Surgical resection and reconstruction was performed in combination with a 3D-printed, patient-specific implant. Custom design features included porous titanium end plates, corrective angulation of the implant to restore sagittal balance, and pedicle screw holes in the 3D implant to assist with insertion of the device. In addition, attachment of the anterior column construct to the posterior pedicle screw construct was possible due to the customized features of the patient-specific implant. CONCLUSIONS An advantage of 3DP is the ability to manufacture patient-specific implants, as in the current case example. Additionally, the use of 3DP has been able to reduce operative time significantly. Surgical procedures can be preplanned using 3DP patient-specific models. Surgeons can train before performing complex procedures, which enhances their presurgical planning in order to maximize patient outcomes. When considering implants and prostheses, the use of 3DP allows a superior anatomic fit for the patient, with the potential to improve restoration of anatomy.

Early hemodynamic performance of the third generation St Jude Trifecta aortic prosthesis: A systematic review and meta-analysis

OBJECTIVE The Trifecta aortic prosthesis is a latest-generation trileaflet stented pericardial valve designed for supra-annular placement in the aortic position. Robust clinical evidence and long-term follow-up data for this new prosthesis are lacking; a systematic review was conducted to assess current evidence. METHODS A comprehensive search from 6 electronic databases was performed, with time period parameters dating from database inception to January 2014. Results utilizing Trifecta prosthesis for aortic valve replacement (AVR) were identified. RESULTS A total of 13 studies with 2549 patients undergoing AVR with this prosthesis were included in this review. The mean proportion of patients with aortic stenosis was 82.4%, with a mean gradient of 47.4 mm Hg, and a pooled effective orifice area (EOA) of 0.74 cm(2). Valve sizes of 21 mm and 23 mm were implanted in 71.3% of patients. The pooled rates of 30-day mortality, cerebrovascular accidents, and acute kidney injuries were 2.7%, 1.9%, and 2.6%, respectively. After implantation, the pooled mean gradient decreased to 9.2 mm Hg, whereas discharge EOA increased to 1.8 cm(2), compared with preoperative parameters. Among included studies with significant heterogeneity detected, most patients had satisfactory patient-prosthesis mismatch, with 2.7% having severe mismatch. CONCLUSIONS The present systematic review demonstrated that short-term AVR with this prosthesis provided excellent early safety and hemodynamic outcomes with acceptable mean gradients and EOA. Long-term follow-up and randomized controlled trials are warranted to confirm the early results.

Hepatic resection for malignant liver tumours in the elderly: a systematic review and meta-analysis: Liver resection for malignant tumours in the elderly

The number of elderly patients undergoing hepatic resection for surgical treatment of benign and malignant cancers is increasing. However, there is limited clinical data on the complications and long‐term survival rates associated with liver surgery in the elderly patients (≥70 years) versus younger patients for malignant liver conditions.

Outcomes of endovascular treatment of basilar artery occlusion in the stent retriever era: a systematic review and meta-analysis

Background Stent retriever thrombectomy has recently been found to be effective for anterior circulation strokes, but its efficacy for basilar artery occlusion (BAO) is unclear. Objective To carry out a systematic review and meta-analysis to analyze the available evidence for the use of stent retrievers for BAO. Methods Two independent reviewers searched six databases for studies reporting outcomes following endovascular treatment for BAO. Results A total of 17 articles (6 prospective and 11 retrospective) were included. The weighted mean age of patients was 67 years (range 59–82) and 59% were male. Thrombolytic drugs were administered intravenously and intra-arterially in 46% (range 0–88%) and 38% (range 0–90%) of patients, respectively. Weighted pooled estimates of successful recanalization (TICI 2b–3) and good outcome (modified Rankin Scale ≤2) were 80.0% (95% CI 70.7% to 88.0%; I2=80.28%; p<0.001) and 42.8% (95% CI 34.0% to 51.8%; I2=61.83%; p=0.002), respectively. Pooled mortality was 29.4% (95% CI 23.9% to 35.3%; I2=37.01%; p=0.087). Incidence of procedure-related complications and symptomatic hemorrhage was 10.0% (95% CI 3.7% to 18.3%; I2=61.05%; p=0.017) and 6.8% (95% CI 3.5% to 10.8%; I2=37.99%; p=0.08), respectively. Conclusions Stent retriever thrombectomy achieves a high rate of recanalization and functional independence while being relatively safe for patients with BAO. Future prospective studies with long-term follow-up are warranted.

Endovascular therapy including thrombectomy for acute ischemic stroke: A systematic review and meta-analysis with trial sequential analysis

One of the primary strategies for the management of acute ischemic stroke is intravenous (IV) thrombolysis with tissue plasminogen activator (t-PA). Over the past decade, endovascular therapies such as the use of stent retrievers to perform mechanical thrombectomy have been found to improve functional outcomes compared to t-PA alone. We aimed to reassess the functional outcomes and complications of IV thrombolysis with and without endovascular treatment for acute ischemic stroke using conventional meta-analysis and trial sequential analysis. Pooled relative risks (RR) and 95% confidence intervals (CI) were calculated for the effect of IV thrombolysis with and without endovascular therapy on functional outcome, mortality and symptomatic intracranial hemorrhage (SICH). Trial sequential analysis was done to strengthen the meta-analysis. We analyzed six randomized controlled trials involving 1943 patients. Patients who received IV thrombolysis with endovascular treatment showed significantly higher rates of excellent functional outcomes (modified Rankin Scale [mRS] 0-1) (RR, 1.75 [95% CI, 1.29-2.39]) compared to those who received IV thrombolysis alone. A similar association was seen for good functional outcomes (mRS 0-2) (RR, 1.56 [95% CI, 1.24-1.96]). Trial sequential analysis demonstrated endovascular treatment increased the RR of a good functional outcome by at least 30% compared to IV thrombolysis alone. There was no significant difference in all-cause mortality for mechanical thrombectomy compared to IV thrombolysis alone or the incidence of SICH at 3month follow-up. Endovascular treatment is more likely to result in a better functional outcome for patients compared to IV thrombolysis alone for acute ischemic stroke.

Hybrid coronary revascularization versus coronary artery bypass surgery: Systematic review and meta-analysis☆

0.61; 95% CI, 0.24–1.58; I 2 = 0%; P = 0.31) or postoperative MACCE (RR, 0.78; 95% CI, 0.34–1.78; I 2 = 0%; P = 0.55), with no significant heterogeneity detected (Fig. 1). From data of 1664 patients, 30-day mortality rates of hybrid and CABG approaches were comparable (RR, 0.88; 95% CI, 0.34–2.33; I 2 = 0%; P = 0.80). Postoperative myocardial infarction (RR, 0.67; 95% CI, 0.49–0.93; I 2 =0 %; P= 0.01) and blood transfusions (RR, 0.54; 95% CI, 0.40–0.74; I 2 =