Frederico Bastos Gonçalves

Calcification of the abdominal aorta as an independent predictor of cardiovascular events: a meta-analysis

Context Abdominal aortic calcification (AAC) is a common finding in patients with atherosclerosis. Objective The aim of this study was to demonstrate the incremental value of AAC in predicting long term cardiovascular (CV) outcome by conducting a meta-analysis of observational studies. Data sources MEDLINE and Cochrane databases. Study selection Longitudinal studies with at least 2 years of follow-up, reporting the influence of AAC on CV outcome of general population patients. Data extraction Four separate end points—coronary events, cerebrovascular events, all CV events and CV related death—were tested for their relationship with AAC at baseline, using weighted random effects meta-analysis. Heterogeneity was calculated using Q and I2 statistic tests. Publication bias was assessed by funnel plot symmetry and trim and fill methods. The importance of calcium quantification was also explored (sensitivity analysis). Results 10 studies were included. An increased relative risk (RR) was found for all end points: for coronary events (five studies, n=11250) 1.81 (95% CI 1.54 to 2.14); for cerebrovascular events (four studies, n=9736) 1.37 (1.22 to 3.54); for all CV events (four studies, n=4960) 1.64 (1.24 to 2.17); and for CV death (three studies, n=4986) 1.72 (1.03 to 2.86). Analysis of studies presenting results in categories (no/minimal, moderate and severe calcification) revealed a stepwise increase in the RR for all end points. Significant heterogeneity was found in the included studies. Sources of heterogeneity were identified in the publication date, duration of follow-up, and mean age and gender differences in the included patient cohorts. Conclusion Existing data suggest that AAC is a strong predictor of CV related events or death in the general population. The predictive impact is greater in more calcified aortas. The generalisability of the meta-analysis is limited by heterogeneity in the coronary events, all CV events and CV death end points.

One-year multicenter results of 100 abdominal aortic aneurysm patients treated with the Endurant stent graft

OBJECTIVE The Endurant (Medtronic, Minneapolis, Minn) is a new stent graft specifically designed to make more patients anatomically eligible for endovascular aneurysm (EVAR). This study presents the 1-year results of 100 consecutive patients with abdominal aortic aneurysms (AAAs) treated with the Endurant stent graft in real-life practice. METHODS All clinical preoperative, operative, postoperative, and 1-year follow-up data of patients with the Endurant stent graft from three tertiary centers were prospectively collected. Patients underwent computed tomographic angiography (CTA) preoperatively, at 1 month, and at 1-year post-EVAR. The first 100 patients with an implantation date at least 1 year before our date of analysis and complete information were included. Clinical data, AAA characteristics, presence of endoleaks, graft migration, and other EVAR-related complications were noted. All values are stated as mean ± SD (range). RESULTS This study included 100 patients with AAAs (88 men) with a mean age of 73 ± 8 years (47 to 87 years), an AAA size of 61 ± 10 mm (31 to 93 mm), an AAA volume of 210 ± 122 mL (69 to 934 mL), a proximal neck length of 33 ± 14 mm (9 to 82 mm), and an infrarenal angulation of 44 ± 25° (0°-108°). Nineteen of the 100 included patients had at least one anatomic characteristic that was considered a violation of the instructions for use (IFU) of the Endurant stent graft. A primary technical success was achieved in 98% of the patients (one additional stent placement in renal artery was required; one unplanned aorto-uni-iliac device placed), with no primary type I or III endoleaks or conversions. A secondary technical success was achieved in all cases. The 30-day mortality was 2% and the first postoperative CTA documented 16 endoleaks (16%; 16 type II). One-year follow-up showed three iliac limb occlusions (3%), one infected stent graft (causing a type Ia endoleak), and five endovascular reinterventions (5%; three to treat iliac limb occlusions, one proximal extension cuff; and one stent in the renal artery). The 1-year all-cause mortality rate was 12% (12 patients) and the AAA-related mortality was 3%. The mean AAA size was significantly smaller after 1 year (diameter, 54 ± 11.8 [32-80] mm; P < .01; volume, 173 ± 119 [42-1028] mL; P < .01), and one graft migration >5 mm and 13 endoleaks were noted (12 type II, 1 type I [neck dilatation]). CONCLUSION The treatment of patients with AAAs with the Endurant stent graft seems to be successful and durable during the first year after EVAR. Despite the wider inclusion criteria for the Endurant, and with 19% of our patients treated outside the IFU, the AAA-related mortality, number of type I or III endoleaks, and reintervention rates are comparable to the results of other stent grafts.

Stent graft composition plays a material role in the postimplantation syndrome.

OBJECTIVE In patients undergoing endovascular aneurysm repair (EVAR), the postimplantation syndrome (PIS), comprising fever and inflammation, occurs frequently. The cause of PIS is unclear, but graft composition and acute thrombus formation may play a role. The objective of this study was to evaluate these possible causes of the inflammatory response after EVAR. METHODS One hundred forty-nine patients undergoing elective EVAR were included. Implanted stent grafts differed mainly in the type of fabric used: either woven polyester (n=82) or expanded polytetrafluorethylene (ePTFE; n=67). Tympanic temperature and C-reactive protein (CRP) were assessed daily during hospitalization. PIS was defined as the composite of a body temperature of ≥38°C coinciding with CRP>10 mg/L. Besides graft composition, the size of the grafts and the volume of new-onset thrombus were calculated using dedicated software, and results were correlated to PIS. RESULTS Implantation of grafts made of polyester was associated with higher postoperative temperature (P<.001), CRP levels (P<.001), and incidence of PIS (56.1% vs 17.9%; P<.001) compared to ePFTE. After multivariate analysis, woven polyester stent grafts were independently associated with an increased risk of PIS (hazard ratio, 5.6; 95% confidence interval, 1.6-19.4; P=.007). Demographics, amount of graft material implanted, or new-onset thrombus had no association with PIS. CONCLUSIONS The composition of stent grafts may play a material role in the incidence of postimplantation syndrome in patients undergoing EVAR. Implantation of stent grafts based on woven polyester was independently associated with a stronger inflammatory response.

Incidence and treatment results of Endurant endograft occlusion

OBJECTIVE The Endurant endograft (Medtronic Inc, Minneapolis, Minn) is a new-generation device specifically developed to perform well in complex abdominal aortic aneurysm anatomy. Previous reports on the 1- and 2-year results of endovascular aneurysm repair (EVAR) with the Endurant endograft showed excellent outcome, including prevention of migration and type I endoleaks, but occurrence and outcome of post-EVAR occlusion have not been determined in a large multicenter patient cohort with midterm follow-up, which is the objective of this study. METHODS Data of consecutive patients treated with the Endurant from December 2007 to April 2012 in three Dutch tertiary vascular referral hospitals were prospectively gathered and retrospectively analyzed. Follow-up consisted of regular office visits, computed tomography angiography at 1 and 12 months after EVAR, and subsequently, duplex ultrasound imaging or computed tomography angiography at regular intervals. Patients with ruptured aneurysms or with earlier abdominal aortic surgery were excluded. The incidence and clinical outcome of endograft occlusions were analyzed. An expert review board assessed all cases in the search for possible causes of occlusion. RESULTS Included were 496 patients (87.7% male), who were a median age of 74 years (range, 68-78 years). Median follow-up was 1.7 years (range, 0-4.6 years). Twenty graft occlusions (4.0%) occurred during follow-up. Median time between primary EVAR and detection of the occlusion was 1 month, with 55% occurring ≤ 60 postoperative days and 90% ≤ 1 year. No association was found between occlusion and sex (P = .28), age (P = .96), or use of an aortouniiliac device (P = .66). Technical error was the considered cause of the occlusion in 12 patients (60%). The estimated freedom from occlusion was 98.4% at 30 days, 95.7% at 1 year, and 95.3% at 3 years. Presenting symptoms of occlusion were acute limb ischemia in 50%. Treatment was surgical (75%) or percutaneous (25%). Successful revascularization was achieved in 17 of 20 patients, but reocclusions occurred in five, resulting in a transfemoral amputation in one patient. Occlusion-related mortality was 0.6% (3 of 496). CONCLUSIONS At a median follow-up of 1.7 years, Endurant endograft occlusion occurred in 4.0% of 496 patients. Most occlusions occurred ≤ 2 months after EVAR, and rarely after 1 year. A technical justification for occlusion could be found for 60% of patients. A more liberal intraoperative and early postoperative (re)intervention strategy may reduce the occlusion rates and improve outcome.

Clinical outcome and morphologic analysis after endovascular aneurysm repair using the Excluder endograft

OBJECTIVE Long-term follow-up after endovascular aneurysm repair (EVAR) is very scarce, and doubt remains regarding the durability of these procedures. We designed a retrospective cohort study to assess long-term clinical outcome and morphologic changes in patients with abdominal aortic aneurysms (AAAs) treated by EVAR using the Excluder endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz). METHODS From 2000 to 2007, 179 patients underwent EVAR in a tertiary institution. Clinical data were retrieved from a prospective database. All patients treated with the Excluder endoprosthesis were included. Computed tomography angiography (CTA) scans were retrospectively analyzed preoperatively, at 30 days, and at the last follow-up using dedicated tridimensional reconstruction software. For patients with complications, all remaining CTAs were also analyzed. The primary end point was clinical success. Secondary end points were freedom from reintervention, sac growth, types I and III endoleak, migration, conversion to open repair, and AAA-related death or rupture. Neck dilatation, renal function, and overall survival were also analyzed. RESULTS Included were 144 patients (88.2% men; mean age, 71.6 years). Aneurysms were ruptured in 4.9%. American Society of Anesthesiologists classification was III/IV in 61.8%. No patients were lost during a median follow-up of 5.0 years (interquartile range, 3.1-6.4; maximum, 11.2 years). Two patients died of medical complications ≤ 30 days after EVAR. The estimated primary clinical success rates at 5 and 10 years were 63.5% and 41.1%, and secondary clinical success rates were 78.3% and 58.3%, respectively. Sac growth was observed in 37 of 142 patients (26.1%). Cox regression showed type I endoleak during follow-up (hazard ratio, 3.74; P = .008), original design model (hazard ratio, 3.85; P = .001), and preoperative neck diameter (1.27 per mm increase, P = .006) were determinants of sac growth. Secondary interventions were required in 32 patients (22.5%). The estimated 10-year rate of AAA-related death or rupture was 2.1%. Overall life expectancy after AAA repair was 6.8 years. CONCLUSIONS EVAR using the Excluder endoprosthesis provides a safe and lasting treatment for AAA, despite the need for maintained surveillance and secondary interventions. At up to 11 years, the risk of AAA-related death or postimplantation rupture is remarkably low. The incidences of postimplantation sac growth and secondary intervention were greatly reduced after the introduction of the low-permeability design in 2004.

Results of endovascular repair of infrarenal aortic aneurysms using the Endurant stent graft

OBJECTIVE Recent reports showed that the Endurant stent graft (Medtronic Cardiovascular, Santa Rosa, Calif) is safe and effective for endovascular repair of abdominal aortic aneurysms (AAAs). However, due to its relatively recent introduction, only short-term follow-up data are available. This study presents the 4-year results using this device. METHODS All clinical data, including detailed anatomic information of the first 100 consecutive patients treated with the Endurant stent graft for an infrarenal AAA in three Dutch high-volume hospitals, were prospectively collected. Computed tomography angiography was routinely performed before the procedure, ≤ 1 month, and at 1 year post-endovascular aneurysm repair. Thereafter, the imaging modality during yearly follow-up was individualized (duplex ultrasound imaging or computed tomography angiography). Patients were classified as within or outside the instructions for use (IFU) for analysis. Study end points were primary clinical success, overall and AAA-related mortality, and sac morphology changes and endoleak during follow-up. Estimates were obtained using Kaplan-Meier plots. RESULTS The study included 100 consecutive patients (88 men) with a median age of 74 years (interquartile range [IQR], 67-79 years) and median AAA diameter of 58 mm (IQR, 55-65 mm), between December 2007 and March 2009. Twenty patients (20%) were treated outside the IFU (18, outside proximal neck IFU, one outside iliac IFU, and one outside both IFUs). Median follow-up was 48 months (IQR, 36-53 months), and no patients were lost. One contained rupture was observed after 1.5 months due to graft infection. No patients had graft migration. Two type Ia endoleaks, 5 type Ib endoleaks, and 15 type II endoleaks were found. Primary clinical success was 97%, 90%, 84% and 77% at 1, 2, 3, and 4 years, respectively. Primary clinical success was comparable for patients treated within or outside IFU (P = .20), although both patients outside iliac IFU needed a secondary iliac intervention. Over time, maximum aneurysm diameter decreased ≥ 5 mm, remained stable, and increased ≥ 5 mm in 58%, 32%, and 10% of the patients, respectively. All-cause mortality was 20% at 4 years, with a 3% AAA-related mortality. CONCLUSIONS The 4-year follow-up data of the Endurant stent graft for AAA treatment shows its use results in a low AAA-related mortality with adequate prevention of rupture or aneurysm growth. Although patients with very challenging anatomy were treated in our series, primary clinical success rates were comparable for patients treated within and outside the IFU. However, both patients outside the iliac IFU needed a secondary iliac intervention. The knowledge of the present results may aid in improving outcomes in the future.

The influence of neck thrombus on clinical outcome and aneurysm morphology after endovascular aneurysm repair

OBJECTIVE This study investigated the influence of significant aneurysm neck thrombus in clinical and morphologic outcomes after endovascular aneurysm repair (EVAR). METHODS The patient population was derived from a prospective EVAR database from two university institutions in The Netherlands from 2004 to 2008. Patients with significant thrombus in the neck (>2 mm in thickness in at least >25% of circumference) were identified as the thrombus group and were compared with the remaining patients without neck thrombus (no-thrombus group), treated within the same period. The primary end point was clinical success. Secondary end points included technical success and rates of decline in renal function. Detailed morphologic analysis of the aortic neck was serially performed for the thrombus group patients to assess changes in thrombus volume. RESULTS The study included 389 patients: 43 (39 men; mean age of 72.3 years) met the criteria for the thrombus group; of these, 31 (72%) had significant thrombus in >50% of the aortic neck circumference, and 8 (19%) had circumferential thrombus >2-mm thick. Median follow-up was 3.34 years (interquartile range, 2.67-4.72). The estimated 5-year clinical success rate was 74% for the thrombus group and 62% for the no-thrombus group (P = .23). Endograft migration was more frequent in the thrombus group (P = .02). Multivariable Cox regression analysis showed a significant association between migration and use of a device without active fixation (hazard ratio, 4.9; 95% confidence interval, 1.31-18.23; P = .018) but not with the presence of neck thrombus (P = .063). No differences were found in the rates of decline in estimated glomerular filtration rate at 30 days and during follow-up between the thrombus and no-thrombus groups. The thrombus volume in the first 10 mm of aortic neck was progressively reduced over time until it was not measurable in most patients, resulting in complete circular attachment of the endograft to the vessel wall. CONCLUSIONS Our findings suggest that the presence of aneurysm neck thrombus has no significant influence on short-term and midterm EVAR results.

Standard endovascular aneurysm repair in patients with wide infrarenal aneurysm necks is associated with increased risk of adverse events

Objective: Endovascular aneurysm repair (EVAR) has progressively expanded to treat more challenging anatomies. Although EVAR in patients with wide infrarenal necks has been reported with acceptable results, there is still controversy regarding the longer‐term outcomes. Our aim is to determine the impact of infrarenal neck diameter on midterm outcome following EVAR with a single endograft with suprarenal fixation. Methods: A retrospective case‐control study was designed using data from a prospective multicenter database. Patients who electively underwent standard EVAR with an Endurant stent graft (Medtronic Ave, Santa Rosa, Calif) for a degenerative abdominal aortic aneurysm from January 2008 to December 2012 in three high‐volume centers in The Netherlands were included. All measurements were obtained using dedicated reconstruction software and center‐lumen line reconstruction. Patients with an infrarenal neck diameter of ≥30 mm were compared with patients with a neck diameter of <30 mm. The primary end point was freedom from neck‐related adverse events (a composite of type Ia endoleak, neck‐related secondary intervention, and endograft migration). Secondary end points were primary clinical success, type Ia endoleak, neck‐related reinterventions, endoleaks, and aneurysm‐related secondary interventions. Results: Four‐hundred twenty‐seven patients were included. Seventy‐four patients (17.3%) with a neck diameter of ≥30 mm were compared with a control group of 353 patients. There were no significant differences at baseline between groups including demographics, comorbidities, baseline aneurysm diameter, infrarenal neck length, suprarenal angulation, or infrarenal neck angulation. Median stent graft oversizing was 12.5% (7.9‐16.1) and 16.6% (12.0‐23.1) in the ≥30‐mm neck‐diameter and control groups, respectively (P < .001). Median follow‐up was 3.1 years (1.2‐4.7) and 4.1 years (2.7‐5.6) for the large neck and control groups, respectively (P < .001). Type Ia endoleaks occurred in 17 patients (4.0%) and were significantly more frequent in patients with ≥30‐mm neck diameter (9.5% vs 2.8%; P = .005). Neck‐related secondary interventions were performed in 20 patients (4.7%) and were also more common among patients with neck diameters of ≥30 mm (9.5% vs 3.7%; P = .04). The 4‐year freedom from neck‐related adverse events were 75% and 95% for the large neck and control groups, respectively (P < .001). On multivariable regression analysis, infrarenal neck diameter of ≥30 mm was an independent risk factor for neck‐related adverse events (odds ratio [OR], 3.8; 95% confidence interval [CI], 1.6‐9.1), type Ia endoleak (OR, 2.7; 95% CI, 1.0‐8.3), and neck‐related secondary interventions (OR, 3.2, 95% CI, 1.1‐9.2). Conclusions: EVAR in patients with large diameter necks is associated with an increased risk of neck‐related adverse events in midterm follow‐up. This may influence the clinical decision regarding choice of repair and toward a more intensive surveillance following EVAR in these patients in the long term.

Familial abdominal aortic aneurysm is associated with more complications after endovascular aneurysm repair

OBJECTIVE A familial predisposition to abdominal aortic aneurysms (AAAs) is present in approximately one-fifth of patients. Nevertheless, the clinical implications of a positive family history are not known. We investigated the risk of aneurysm-related complications after endovascular aneurysm repair (EVAR) for patients with and without a positive family history of AAA. METHODS Patients treated with EVAR for intact AAAs in the Erasmus University Medical Center between 2000 and 2012 were included in the study. Family history was obtained by written questionnaire. Familial AAA (fAAA) was defined as patients having at least one first-degree relative affected with aortic aneurysm. The remaining patients were considered sporadic AAA. Cardiovascular risk factors, aneurysm morphology (aneurysm neck, aneurysm sac, and iliac measurements), and follow-up were obtained prospectively. The primary end point was complications after EVAR, a composite of endoleaks, need for secondary interventions, aneurysm sac growth, acute limb ischemia, and postimplantation rupture. Secondary end points were specific components of the primary end point (presence of endoleak, need for secondary intervention, and aneurysm sac growth), aneurysm neck growth, and overall survival. Kaplan-Meier estimates for the primary end point were calculated and compared using log-rank (Mantel-Cox) test of equality. A Cox-regression model was used to calculate the independent risk of complications associated with fAAA. RESULTS A total of 255 patients were included in the study (88.6% men; age 72 ± 7 years, median follow-up 3.3 years; interquartile range, 2.2-6.1). A total of 51 patients (20.0%) were classified as fAAA. Patients with fAAA were younger (69 vs 72 years; P = .015) and were less likely to have ever smoked (58.8% vs 73.5%; P = .039). Preoperative aneurysm morphology was similar in both groups. Patients with fAAA had significantly more complications after EVAR (35.3% vs 19.1%; P = .013), with a twofold increased risk (adjusted hazard ratio, 2.1; 95% confidence interval, 1.2-3.7). Secondary interventions (39.2% vs 20.1%; P = .004) and aneurysm sac growth (20.8% vs 9.5%; P = .030) were the most important elements accounting for the difference. Furthermore, a trend toward more type I endoleaks during follow-up was observed (15.6% vs 7.4%; P = .063) and no difference in overall survival. CONCLUSIONS The current study shows that patients with a familial form of AAA develop more aneurysm-related complications after EVAR, despite similar AAA morphology at baseline. These findings suggest that patients with fAAA form a specific subpopulation and create awareness for a possible increase in the risk of complications after EVAR.

Conservative management of persistent aortocaval fistula after endovascular aortic repair

Endovascular repair is a valid alternative for patients with abdominal aortic aneurysms. However, in patients with concomitant aortocaval fistulas, type II endoleaks may result in a persistent communication between the aneurysm sac and the inferior vena cava. In these patients, prompt closure of the persistent fistula has been advocated. We present a patient with an abdominal aortic aneurysm, with aortocaval fistula, who was managed endovascularly. Aneurysm sac shrinkage was observed despite persistent aortocaval communication due to type II endoleak. This case demonstrates that conservative management of type II endoleaks associated with persistent aortocaval fistulas is possible and may result in favorable aneurysm sac remodelling.