Ashraf Al-Dadah

Dyslipidemia in Patients with Chronic and End-Stage Kidney Disease

In this review, we discuss the physiology, diagnosis and treatment of dyslipidemia in patients with chronic and end-stage renal disease. The recent important clinical trials in patients with chronic kidney disease and dyslipidemia are reviewed. Because of the lack of evidence in treating lipid abnormalities in this specific patient population, we propose that future studies should focus on the pathophysiological mechanisms and treatment of dyslipidemia in this special patient population.

Proximal balloon occlusion versus distal filter protection in carotid artery stenting: A meta-analysis and review of the literature

Carotid artery stenting (CAS) is typically performed using embolic protection devices (EPDs) as a means to reduce the risk of procedure‐related stroke. In this study, we compared procedural morbidity and mortality associated with distal (D‐EPD) vs. proximal (P‐EPD) protection.

Endovascular versus surgical treatment for acute limb ischemia: a systematic review and meta-analysis of clinical trials

BACKGROUND A number of small studies have suggested that outcomes following endovascular (ENDO) therapy are comparable to those following surgical (SURG) revascularization for patients presenting with acute limb ischemia (ALI). We sought to compare mortality, limb amputation and recurrent ischemia across both revascularization strategies. METHODS A comprehensive database search of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases from January 1990 through January 2016 was performed to identify studies of ENDO versus SURG for ALI. Two independent reviewers selected studies and extracted the data. Random-effects meta-analysis was used to pool results across studies. Heterogeneity of treatment effect among trials was assessed using the I2 statistics. The primary endpoints were mortality and limb amputation at 1 month, 6 and 12 months. Secondary endpoint was recurrent ischemia at one year. RESULTS A total of 1,773 patients were included from six studies (five randomized prospective and one observational retrospective) comparing ENDO and SURG in the setting of ALI. The mean age was 67 years and 65% of patients were male. There were no differences in mortality between the two groups at 1 month [risk ratio (RR) for ENDO vs. SURG is 0.70; 95% confidence interval (CI), 0.33 to 1.50], 6 months (RR 1.12; CI, 0.78 to 1.61) or 12 months (RR 0.74; CI, 0.29 to 1.85). Similarly, there was no significant difference in amputation rates between ENDO and SURG at 1 month (RR 0.75; CI, 0.40 to 1.42), 6 months (RR 0.87; CI, 0.52 to 1.48) or 12 months (RR 0.81; CI, 0.55 to 1.18). When looking into secondary outcomes, recurrent ischemia was not different between the two groups (RR 1.12; CI, 0.75 to 1.67). CONCLUSIONS In patients presenting with ALI (<2 weeks of duration), ENDO and SURG approaches have similar rates of short-term and 12 month mortality, limb amputation and recurrent ischemia.

Comparison of Outcomes of ST-Elevation Myocardial Infarction Treated by Percutaneous Coronary Intervention During Off-Hours Versus On-Hours

Previous studies have reported worse outcomes and longer door-to-balloon times (DBTs) in patients presenting with ST-elevation myocardial infarction (STEMI) after normal working hours, during weekends, and on holidays (off-hours) compared with normal business hours (on-hours). Recent studies, however, have reported similar outcomes regardless of presentation time. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were queried from January 1990 through December 2016. Only studies comparing STEMI outcomes during off-hours versus on-hours with percutaneous coronary intervention were included. A random-effects meta-analysis model was used to pool outcomes across the studies. Clinical end points included short- (<30 days of presentation), intermediate- (at 1 to 2 years), and long-term (at 3 to 4 years) stent thrombosis, mortality, recurrent myocardial infarction (MI), and major adverse cardiovascular events (MACEs). A total of 86,776 patients (62 years and 74.5% male) were identified from 39 studies. There was no significant difference between both groups with regard to mean DBT (odds ratio [OR] 0.74, 95% confidence interval [CI] -2.73 to 4.22, p = 0.67) or median DBT (p = 0.19). There was no significant difference between the 2 groups for short-term end points including mortality (OR 1.11, 95% CI 0.99 to 1.25, p = 0.08), MI (OR 1.25, 95% CI 0.90 to 1.74, p = 0.18), MACE (OR 1.06, 95% CI 0.93 to 1.20, p = 0.40), or stent thrombosis (OR 1.23, 95% CI 0.83 to 1.82, p = 0.31). Similarly, intermediate-term end points were not statistically different for mortality (OR 0.97, 95% CI 0.89 to 1.05, p = 0.46), MI (OR 0.86, 95% CI 0.73 to 1.02, p = 0.08), or MACE (OR 1.00, 95% CI 0.92 to 1.08, p = 0.98). Long-term end points did not differ statistically between groups for mortality (OR 0.95, 95% CI 0.83 to 1.09, p = 0.46), MI (OR 1.19, 95% CI 0.77 to 1.84, p = 0.44), or MACE (OR 0.98, 95% CI 0.89 to 1.08, p = 0.67). In conclusion, patients presenting with STEMI during off-hours and treated with percutaneous coronary intervention had similar short-, intermediate-, and long-term outcomes compared with patients presenting during on-hours. DBT was not affected by the time of presentation.

Fractional flow reserve versus angiography guided percutaneous coronary intervention: An updated systematic review

To compare outcomes of fractional flow reserve (FFR) to angiography (ANGIO) guided percutaneous coronary intervention (PCI).

Thoracic endovascular repair versus medical management for acute uncomplicated type B aortic dissection

Current treatment options and outcomes for acute uncomplicated thoracic Type‐B aortic dissection (TBAD) remain unclear between medical management (MED) and thoracic endovascular aortic repair (TEVAR). In this study we aim to compare both strategies in terms of all‐cause mortality, aortic dilation, and aortic rupture.

Bivalirudin versus unfractionated heparin in peripheral vascular interventions

BACKGROUND A number of studies suggest that bivalirudin (BIV) is associated with similar efficacy but reduced bleeding when compared with unfractionated heparin (UFH) in patients undergoing peripheral vascular interventions (PVI). METHODS A comprehensive literature search was conducted with the electronic databases MEDLINE, EMBASE and CENTRAL. These were queried to identify studies comparing BIV with UFH in PVI. Study endpoints included total bleeding events, major and minor bleeding events and procedural success. Random-effects meta-analysis method was used to pool endpoint odds ratios (OR) for both UFH and BIV with 95% confidence intervals (CI). RESULTS A total of 12,335 patients (70.6 years; 59.7% male) were included from seven observational cohort studies (two prospective and five retrospective) comparing outcomes between BIV and UFH during PVI between January 2000 and May 2017. Compared with BIV, UFH was associated with significantly higher total bleeding, (OR 1.52 with 95% CI 1.11 to 2.09, p = 0.009), major bleeding (OR 1.38 with 95% CI 1.13 to 1.68, p = 0.002), and minor bleeding (OR 1.51 with 95% CI 1.09 to 2.08, p = 0.01). Procedural success rates were not different between the two groups (BIV vs HEP: OR 0.90 with 95% CI 0.49 to 1.64, p = 0.72) CONCLUSION: Compared with BIV, UFH was associated with more bleeding when used during PVI. There was no significant difference in procedural success between the two anticoagulation strategies.

Rebuttal regarding: Proximal occlusion versus distal filter for cerebral protection during carotid stenting: The positive results of MO.MA trials

We congratulate the commentators for the secondary analysis they have done regarding the MoMa device and we highly appreciate their keen interest and knowledge. Protected carotid artery stenting (CAS) remains an ongoing debate in regards to device selection. In our recent analysis, we compared the distal filter protection device (DEPD) to proximal balloon occlusion (P-EPD). We also alluded to the same point the commentators mentioned demonstrating the advantage of P-EPD had when looking into the six analyzed studies [1–6] in regards to ischemic lesions on diffusion weighted-magnetic resonance imaging (DW-MRI) with no statistical differences in stroke incidence [7]. Over the past decade, several studies have been conducted evaluating the safety of the MoMA device; the ARMOUR trail (ProximAl PRotection with the MO.MA Device During CaRotid Stenting) was a recent trial that led to US Food and Drug Administration (FDA) approval of this device. There were 262 patients from 25 sites in the USA and Europe enrolled demonstrating 30-day mortality, myocardial infarction and stroke was 2.7%. The 30-day major stroke rate was 0.9%. DW-MRI was not used in this study [8]. P-EPD may be theoretically superior to D-EPD for stroke prevention since the carotid lesion remains untouched with no lesion crossing prior to the protection process. Montorsi et al. divided the CAS procedure into several phases and measured the incidence of microembolic signals (MES) at transcranial Doppler echography in each phase. Overall, MoMa was associated with lower incidence of MES in most of CAS procedure phases. Interestingly, the highest incidence of microembolic signals associated with P-EPD was registered during deflation of the proximal balloon, which may indicate suboptimal protection [1]. The advantages associated with P-EPD may be less relevant in diabetic or symptomatic patients due to intrinsic lesion features that may lead to acute and subacute prolapse of plaque components even after stent implantation once cerebral protection is completely removed [9,10]. DW-MRI lesions have been used as surrogate measures of EPD efficacy. Contralateral lesions were utilized in assessing the procedural complexity since they originate from aortic arch instrumentation prior to EPD’s deployment [11]. The neuronal injury may depend on the size of the embolic particle. Although the minimum particle size that causes ischemic cerebral events has not been specified, a study showed that embolic particles 200–500 lm in diameter induced neuronal injury while particles 200 lm in diameter did not. All filters have the ability to capture particles 200 lm in diameter [12]. The clinical impact of these lesions in asymptomatic patients continues to be a matter of debate. In a study performed by Akkaya et al., neurocognitive tests were performed before and six months after CAS. Cerebral microembolism was not associated with neurocognitive decline [5]. Similarly, a large retrospective registry did not support the association of new cerebral lesions with major adverse events at follow-up [13]. This lack of association raises doubts about the role of surrogate endpoints in future investigations of protected CAS. We did not make an argument favoring the use of one device over the other but we point out that the majority CAS protection devices studies were not powered for clinical outcomes, since they focused on surrogate endpoints, such as imaging-based measures of efficacy. Most of the procedure risk estimates were derived from studies in which patients were treated with different devices [10]. We also would like to point out that there are several other unmeasured confounders worth mentioning including: operator experience, operator specialty, and anatomic/lesions characteristics (e.g., external carotid artery stenosis preventing effective proximal protection device placement) as well as patient selection (age and diabetic status are among the baseline clinical patient

Hemorrhagic and ischemic outcomes of Heparin vs. Bivalirudin in carotid artery stenting: A meta-analysis of studies

Bivalirudin, has been shown to have comparable efficacy and better safety profile when compared to unfractionated heparin (UFH) in percutaneous coronary interventions. Bivalirudins safety in carotid artery stenting (CAS) was associated with better outcomes than heparin in some studies. In this Meta analysis we examine the hemorrhagic and ischemic outcomes associated with Bivalirudin compared to UFH during CAS.

Percutaneous Angioplasty versus Atherectomy for Treatment of Symptomatic Infra-Popliteal Arterial Disease

BACKGROUND Outcomes for debulking by atherectomy (ATH) for adjunctive treatment of below the knee (BTK) symptomatic arterial disease compared to percutaneous transluminal angioplasty alone (PTA) are unclear. METHODS MEDLINE, EMBASE, PubMed and the Cochrane Central Register of Controlled Trials were queried from between 2000 and 2017 including studies comparing PTA alone to PTA-ATH. Random effect meta-analysis model was used to pool the data across the studies. Study endpoints included: vessel dissection, residual stenosis (<30%), mortality at 12months and amputation rates at 1 and 12months. RESULTS A total of 2587 patients (72.9years; 63% male) were included from 4 studies (2 prospective, one of which was randomized, and 2 retrospective) comparing PTA alone to ATH-PTA in patients with symptomatic infra-popliteal disease. There was no significant difference between the two approaches in terms of vessel dissection [OR 3.73 with 95% CI 0.83 to 16.64, p=0.08] or residual stenosis [OR 0.41 with 95% CI 0.11 to 1.60, p=0.18]. Clinical outcomes did not differ in terms of 12month mortality [OR 3.47 with 95% CI 0.15 to 81.37, p=0.44], or limb amputation at 1month [OR 1.23 with 95% CI 0.91 to 1.67, p=0.18] or 12months [OR: 1.02 with 95% CI 0.83 to 1.26, p=0.83]. CONCLUSION In patients undergoing (BTK) intervention, PTA alone and ATH-PTA was associated with similar outcomes in terms of vessel dissection and residual stenosis, mortality at 12months, and limb amputation at 1 or 12months.