Endovascular Transvenous versus Open Femoropopliteal Bypass.

Background and Objectives: Lower extremity arterial disease is one of the most prevalent manifestations of atherosclerosis. The results from numerous studies regarding the best revascularization method of an occluded superficial femoral artery have been conflicting. The aim of this study was to compare the patency of transvenous endovascular with open femoropopliteal bypass, both with vein and prosthetic grafts. To our knowledge, a direct patency comparison between transvenous endovascular and open femoropopliteal bypass has not been published. This could help elucidate which method is preferable and in which cases. Materials and Methods: Patients with complex TASC-C and D SFA lesions were offered endovascular transvenous or open bypass. A total of 384 consecutive patients with PAD requiring surgical treatment were evaluated for inclusion in this study. Three-year follow-up data were collected for 52 endovascular procedures, 80 prosthetic grafts, and 44 venous bypass surgeries. Bypass patency was investigated by Duplex US every 6 months. Kaplan-Meier plots were used to analyze primary, primary-assisted, and secondary patency for endovascular transvenous, autovenous, and prosthetic bypasses. Results: Primary, primary-assisted, and secondary patency in venous group at 3 years was 70.5%, 77.3%, and 77.3%, respectively. In the endovascular transvenous group, primary, primary-assisted, and secondary patency at 3 years was 46.2%, 69.2%, and 76.9%, respectively. The lowest patency rates at 3 years were noted in the prosthetic graft group with 22.5% primary, 26.6% primary-assisted, and 28.2% secondary patency. Conclusions: The saphenous vein is the best graft to perform in above-the-knee femoropopliteal bypass. Transvenous endovascular bypass is a viable option with comparable primary-assisted and secondary patency. Primary patency is substantially lower for endovascular transvenous compared to venous bypass. Patients treated with endovascular transvenous bypass will require a significant number of secondary procedures to provide optimal patency. Prosthetic grafts should only be used if no other option for bypass is available.

Diagnosis and treatment of ischemia-producing coronary stenoses improves 5-year survival of patients undergoing major vascular surgery.

OBJECTIVE: Patients undergoing vascular surgery procedures have poor long-term survival due to coexisting coronary artery disease (CAD), which is often asymptomatic, undiagnosed, and undertreated. We sought to determine whether preoperative diagnosis of asymptomatic (silent) coronary ischemia using coronary computed tomography (CT)-derived fractional flow reserve (FFRCT) together with postoperative ischemia-targeted coronary revascularization can reduce adverse cardiac events and improve long-term survival following major vascular surgery METHODS: In this observational cohort study of 522 patients with no known CAD undergoing elective carotid, peripheral, or aneurysm surgery we compared two groups of patients. Group I included 288 patients enrolled in a prospective Institutional Review Board-approved study of preoperative coronary CT angiography (CTA) and FFRCT testing to detect silent coronary ischemia with selective postoperative coronary revascularization in addition to best medical therapy (BMT) (FFRCT guided), and Group II included 234 matched controls with standard preoperative cardiac evaluation and postoperative BMT alone with no elective coronary revascularization (Usual Care). In the FFRCT group, lesion-specific coronary ischemia was defined as FFRCT ≤0.80 distal to a coronary stenosis, with severe ischemia defined as FFRCT ≤0.75. Results were available for patient management decisions. Endpoints included all-cause death, cardiovascular death, myocardial infarction (MI), and major adverse cardiovascular events (MACE [death, MI, or stroke]) during 5-year follow-up. RESULTS: The two groups were similar in age, gender, and comorbidities. In FFRCT, 65% of patients had asymptomatic lesion-specific coronary ischemia, with severe ischemia in 52%, multivessel ischemia in 36% and left main ischemia in 8%. The status of coronary ischemia was unknown in Usual Care. Vascular surgery was performed as planned in both cohorts with no difference in 30-day mortality. In FFRCT, elective ischemia-targeted coronary revascularization was performed in 103 patients 1 to 3 months following surgery. Usual Care had no elective postoperative coronary revascularizations. At 5 years, compared with Usual Care, FFRCT guided had fewer all-cause deaths (16% vs 36%; hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.22-0.60; P < .001), fewer cardiovascular deaths (4% vs 21%; HR, 0.11; 95% CI, 0.04-0.33; P < .001), fewer MIs (4% vs 24%; HR, 0.13; 95% CI, 0.05-0.33; P < .001), and fewer MACE (20% vs 47%; HR, 0.36; 95% CI, 0.23-0.56; P < .001). Five-year survival was 84% in FFRCT compared with 64% in Usual Care (P < .001). CONCLUSIONS: Diagnosis of silent coronary ischemia with ischemia-targeted coronary revascularization in addition to BMT following major vascular surgery was associated with fewer adverse cardiovascular events and improved 5-year survival compared with patients treated with BMT alone as per current guidelines.

Three-Year Patency Results following Endovascular Transvenous Femoropopliteal Bypass.

Background and Objectives: Peripheral artery disease is one of the most common vascular pathologies. There is an ongoing debate among specialists on whether open or endovascular revascularization is preferred in cases of complex superficial femoral artery (SFA) lesions. The purpose of this study was to assess patency results of a relatively new transvenous endovascular bypass device. This could add to existing evidence and aid in comparison between open and endovascular bypass. Materials and Methods: Patients with complex TASC-C and D SFA lesions who had indications for revascularization were identified. Prospective analysis of stent graft patency from 54 transvenous femoropopliteal bypass procedures was performed. Patency was assessed by Duplex ultrasound every six months. Kaplan-Meier analysis was performed to assess primary, primary-assisted, and secondary patency of transvenous bypass. Results: Following endovascular transvenous femoropopliteal bypass, 3-year graft primary, primary-assisted, and secondary patency was 43.8%, 66.3%, and 73.9%, respectively. Conclusions: Transvenous endovascular femoropopliteal bypass is a viable option for selected patients who lack adequate saphenous vein or have comorbidities that increase the risk of open femoropopliteal bypass. Strict post-operative follow-up is necessary to improve patency rates.

Coronary revascularization of patients with silent coronary ischemia may reduce the risk of myocardial infarction and cardiovascular death after carotid endarterectomy.

BACKGROUND: Major adverse cardiac events (MACEs) are the primary cause of death after carotid endarterectomy (CEA). We sought to determine whether selective coronary revascularization of CEA patients with asymptomatic coronary ischemia can reduce the risk of MACEs, myocardial infarction (MI), and cardiac death after endarterectomy compared with CEA patients receiving standard cardiac evaluation and care. METHODS: Two groups of patients with no cardiac history or symptoms undergoing elective CEA were compared. Group I: patients enrolled in a prospective study of noninvasive preoperative cardiac evaluation using coronary computed tomography (CT)-derived fractional flow reserve (FFRCT) to detect asymptomatic (silent) coronary ischemia with selective postoperative coronary revascularization. Group II: matched Control patients with standard preoperative cardiac evaluation and no postoperative coronary revascularization. Lesion-specific coronary ischemia in group I was defined as FFRCT ≤ 0.80 distal to coronary stenosis with severe ischemia defined as FFRCT ≤ 0.75. End points included MACEs, cardiac death, MI, cardiovascular (CV) death, stroke, and all-cause death through 3-year follow-up. RESULTS: Group I (n = 100) and group II (n = 100) patients were similar in age (68 vs 67 years), gender (65% vs 62% male), comorbidities, and indications for CEA (53% vs 48% symptomatic carotid stenosis). In group I, FFRCT analysis revealed lesion-specific coronary ischemia in 57% of patients, severe coronary ischemia in 44%, left main ischemia in 7%, and multivessel ischemia in 28%. The status of coronary ischemia in group II was unknown. CEA was performed without complications in both groups, and all patients received optimal postoperative medical therapy. In group I, elective coronary revascularization was performed in 33 patients (27 percutaneous coronary intervention; 6 coronary artery bypass grafting) 1 to 3 months after CEA. Group II patients had no elective coronary revascularization. During 3-year follow-up, compared with group II, group I patients had fewer MACEs (4% vs 17%, hazard ratio [HR]: 0.21 [95% confidence interval (CI): 0.07-0.63], P = .004), fewer cardiac deaths (2% vs 9%, HR: 0.20 [95% CI: 0.04-0.95], P = .030), fewer MIs (3% vs 17%, HR: 0.16 [95% CI: 0.05-0.54], P = .001), and fewer CV deaths (2% vs 12%, HR: 0.16 [95% CI: 0.004-0.07], P = .009). There were no significant differences in the rates of stroke or all-cause death. CONCLUSIONS: Preoperative diagnosis of silent coronary ischemia with selective coronary revascularization after CEA may reduce the risk of MACEs, cardiac death, MI, and CV death during 3-year follow-up compared with CEA patients receiving standard cardiac evaluation and care.

Diagnosis of silent coronary ischemia with selective coronary revascularization might improve 2-year survival of patients with critical limb-threatening ischemia.

BACKGROUND: Patients with critical limb-threatening ischemia (CLTI) have had poor long-term survival after lower extremity revascularization owing to coexistent coronary artery disease. A new cardiac diagnostic test, coronary computed tomography-derived fractional flow reserve (FFRCT), can identify patients with ischemia-producing coronary stenosis who might benefit from coronary revascularization. We sought to determine whether the diagnosis of silent coronary ischemia before limb salvage surgery with selective postoperative coronary revascularization can reduce the incidence of adverse cardiac events and improve the survival of patients with CLTI compared with standard care. METHODS: Patients with CLTI and no cardiac history or symptoms who had undergone preoperative testing to detect silent coronary ischemia with selective postoperative coronary revascularization (group I) were compared with patients with standard preoperative cardiac clearance and no elective postoperative coronary revascularization (group II). Both groups received guideline-directed medical care. Lesion-specific coronary ischemia in group I was defined as FFRCT of ≤0.80 distal to a stenosis, with severe ischemia defined as FFRCT of ≤0.75. The endpoints included all-cause death, cardiovascular (CV) death, myocardial infarction (MI), major adverse CV events (i.MACE; CV death, MI, unplanned coronary revascularization, stroke) through 2 years of follow-up. RESULTS: Groups I (n = 111) and II (n = 120) were similar in age (66 ± 9 vs 66 ± 7 years), gender (78% vs 83% men), comorbidities, and surgery performed. In group I, unsuspected, silent coronary ischemia was found in 71 of 103 patients (69%), with severe ischemia in 58% and left main coronary ischemia in 8%. Elective postoperative coronary revascularization was performed in 47 of 71 patients with silent ischemia (66%). In group II, the status of silent coronary ischemia was unknown. The median follow-up was >2 years for both groups. The 2-year outcomes for groups I and II were as follows: all-cause death, 8.1% and 20.0% (hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.18-0.84; P = .016); CV death, 4.5% and 13.3% (HR, 0.32; 95% CI, 0.11-0.88; P = .028); MI, 6.3% and 17.5% (HR, 0.33; 95% CI, 0.14-0.79; P = .012); and major adverse CV events, 10.8% and 23.3% (HR, 0.44; 95% CI, 0.22-0.88; P = .021), respectively. CONCLUSIONS: The preoperative evaluation of patients with CLTI and no known coronary artery disease using coronary FFRCT revealed silent coronary ischemia in two of every three patients. Selective coronary revascularization of patients with silent coronary ischemia after recovery from limb salvage surgery resulted in fewer CV deaths and MIs and improved 2-year survival compared with patients with CLTI who had received standard cardiac evaluation and care. Prospective controlled studies are required to further define the role of FFRCT in the evaluation and treatment of patients with CLTI.

Diagnosis and management of silent coronary ischemia in patients undergoing carotid endarterectomy.

BACKGROUND: Coronary artery disease is the primary cause of death in patients with carotid artery disease and silent ischemia is a marker for adverse coronary events. A new noninvasive cardiac diagnostic test, coronary computed tomography-derived fractional flow reserve (FFRCT) can reliably identify ischemia-producing coronary stenosis in patients with coronary artery disease and help to select patients for coronary revascularization. The purpose of this study is to determine the prevalence of silent coronary ischemia in patients undergoing carotid endarterectomy (CEA) and to evaluate the usefulness of FFRCT in selecting patients for coronary revascularization to decrease cardiac events and improve survival. METHODS: Patients with no cardiac history or symptoms admitted for elective CEA were enrolled in a prospective, open-label, institutional review board-approved study and underwent preoperative coronary computed tomography angiography (CTA) and FFRCT with results available to physicians for patient management. Lesion-specific coronary ischemia was defined as FFRCT of 0.80 or less distal to a focal coronary stenosis with an FFRCT of 0.75 or less, indicating severe ischemia. Primary end point was incidence of major adverse cardiovascular events (MACE; defined as cardiovascular death, myocardial infarction, or stroke) at 30 days and 1 year. RESULTS: Coronary CTA and FFRCT was performed in 90 CEA patients (age 67 ± 8 years; male 66%). Lesion-specific coronary ischemia was found in 51 patients (57%) with a mean FFRCT of 0.71 ± 0.14. Severe coronary ischemia was present in 39 patients (43%), 26 patients had multivessel ischemia, and 5 had left main disease. CEA was performed as scheduled in all patients with no postoperative deaths or myocardial infarctions. There were no MACE events at 30 days. After recovery from surgery, 36 patients with significant lesion-specific ischemia underwent coronary angiography with coronary revascularization (percutaneous coronary intervention or coronary artery bypass grafting) in 30 patients (33%). Survival at 1 year was 100% and freedom from MACE was 98%. CONCLUSIONS: Patients undergoing CEA have a high prevalence of unsuspected (silent) coronary ischemia, which may place them at risk for coronary events. Preoperative diagnosis of silent ischemia using CTA and FFRCT can identify high-risk patients and help to guide patient management. Selective postoperative coronary revascularization of patients with significant ischemia may decrease the risk of cardiac events and improve survival, but longer follow-up is needed and prospective, controlled trials are indicated.

Pre-operative Diagnosis of Silent Coronary Ischaemia May Reduce Post-operative Death and Myocardial Infarction and Improve Survival of Patients Undergoing Lower Extremity Surgical Revascularisation.

OBJECTIVE: Patients undergoing peripheral vascular surgery have increased risk of death and myocardial infarction (MI), which may be due to unsuspected (silent) coronary ischaemia. The aim was to determine whether pre-operative diagnosis of silent ischaemia using coronary computed tomography (CT) derived fractional flow reserve (FFRCT) can facilitate multidisciplinary care to reduce post-operative death and MI, and improve survival. METHODS: This was a single centre prospective study with historic controls. Patients with no cardiac symptoms undergoing lower extremity surgical revascularisation with pre-operative coronary CTA-FFRCT testing were compared with historic controls with standard pre-operative testing. Silent coronary ischaemia was defined as FFRCT ≤ 0.80 distal to coronary stenosis with FFRCT ≤ 0.75 indicating severe ischaemia. End points included cardiovascular (CV) death, MI, and all cause death through one year follow up. RESULTS: There were no statistically significant differences between CT angiography (CTA-FFRCT) (n = 135) and control (n = 135) patients with regard to age (66 ± 8 years), sex, comorbidities, or surgery performed. Coronary CTA showed ≥ 50% stenosis in 70% of patients with left main stenosis in 7%. FFRCT revealed silent coronary ischaemia in 68% of patients with severe ischaemia in 53%. The status of coronary ischaemia was unknown in the controls. At 30 days, CV death and MI in the CTA-FFRCT group were not statistically significantly different from controls (0% vs. 3.7% [p = .060] and 0.7% vs. 5.2% [p = .066], respectively). Post-operative coronary revascularisation was performed in 54 patients to relieve silent ischaemia (percutaneous coronary intervention in 47, coronary artery bypass graft in seven). At one year, CTA-FFRCT patients had fewer CV deaths (0.7% vs. 5.9%; p = .036) and MIs (2.2% vs. 8.1%; p = .028) and improved survival (p = .018) compared with controls. CONCLUSION: Pre-operative diagnosis of silent coronary ischaemia in patients undergoing lower extremity revascularisation surgery can facilitate multidisciplinary patient care with selective post-operative coronary revascularisation. This strategy reduced post-operative death and MI and improved one year survival compared with standard care.

Initial Clinical Experience Using the Low-Profile Altura Endograft System With Double D-Shaped Proximal Stents for Endovascular Aneurysm Repair.

PURPOSE: To report the initial clinical results of endovascular aneurysm repair (EVAR) using the low-profile (14-F) Altura Endograft System, which features a double "D-shaped" stent design with suprarenal fixation and modular iliac components that are deployed from distal to proximal. METHODS: From 2011 to 2015, 90 patients (mean age 72.8±8.3 years; 79 men) with abdominal aortic aneurysm (AAA; mean diameter 53.8±5.7 mm) were treated at 10 clinical sites in 2 prospective, controlled clinical studies using the Altura endograft. Outcomes evaluated included mortality, major adverse events (MAEs: all-cause death, stroke, paraplegia, myocardial infarction, respiratory failure, bowel ischemia, and blood loss ≥1000 mL), and clinical success (freedom from procedure-related death, type I/III endoleak, migration, thrombosis, and reintervention). RESULTS: Endografts were successfully implanted in 89 (99%) patients; the single failure was due to delivery system malfunction before insertion in the early-generation device. One (1%) patient died and 4 patients underwent reinterventions (1 type I endoleak, 2 iliac limb stenoses, and 1 endograft occlusion) within the first 30 days. During a median follow-up of 12.5 months (range 11.5-50.9), there were no aneurysm ruptures, surgical conversions, or AAA-related deaths. The cumulative MAE rates were 3% (3/89) at 6 months and 7% (6/89) at 1 year. Two patients underwent coil embolization of type II endoleaks at 6.5 months and 2.2 years, respectively. Clinical success was 94% (84/89) at 30 days, 98% (85/87) at 6 months, and 99% (82/83) at 1 year. CONCLUSION: Early results suggest that properly selected AAA patients can be safely treated using the Altura Endograft System with favorable midterm outcome. Thus, further clinical investigation is warranted to evaluate the role of this device in the treatment of AAA.

Effect of the ratio of coronary arterial lumen volume to left ventricle myocardial mass derived from coronary CT angiography on fractional flow reserve.

BACKGROUND: We hypothesize that in patients with suspected coronary artery disease (CAD), lower values of the ratio of total epicardial coronary arterial lumen volume to left ventricular myocardial mass (V/M) result in lower fractional flow reserve (FFR). METHODS: V/M was computed in 238 patients from the NXT trial who underwent coronary computed tomography angiography (CTA), quantitative coronary angiography (QCA) and FFR measurement in 438 vessels. Nitroglycerin was administered prior to CT, QCA and FFR acquisition. The V/M ratio was quantified on a patient-level from CT image data by segmenting the epicardial coronary arterial lumen volume (V) and the left ventricular myocardial mass (M). Calcified and noncalcified plaque volumes were quantified using semi-automated software. RESULTS: The median value of V/M (18.57 mm3/g) was used to define equal groups of low and high V/M patients. Patients with low V/M had greater diameter stenosis by QCA, more plaque and lower FFR (0.80 ± 0.12 vs. 0.87 ± 0.08; P < 0.0001) than those with high V/M. A total of 365 vessels in 202 patients had QCA stenosis ≤50% and measured FFR. In these patients, those with low V/M had higher percent diameter stenosis by QCA, greater total plaque volume and lower FFR (0.81 ± 0.12 vs. 0.88 ± 0.07; P < 0.0001) than those with high V/M. In multivariate logistic regression analysis, V/M was an independent predictor of FFR ≤0.80 (all p-values < 0.001). CONCLUSIONS: Patients with a low V/M ratio have lower FFR overall and in non-obstructive CAD, independent of plaque measures.

FFR Derived From Coronary CT Angiography in Nonculprit Lesions of Patients With Recent STEMI.

OBJECTIVES: This study sought to determine the diagnostic performance of noninvasive fractional flow reserve (FFR) derived from coronary computed tomography angiography (CTA) (FFRCT) for the diagnosis of lesion-specific ischemia in nonculprit vessels of patients with recent in ST-segment elevation myocardial infarction (STEMI). BACKGROUND: In patients with stable angina, FFRCT has high diagnostic performance in identification of ischemia-causing lesions. The potential value of FFRCT for assessment of multivessel disease in patients with recent STEMI has not been evaluated. METHODS: Coronary CTA with calculation of FFRCT and invasive coronary angiography with FFR were performed 1 month after STEMI in patients with multivessel disease. Coronary CTA and invasive coronary angiography stenosis >50% were considered obstructive. Lesion-specific ischemia was assumed if FFRCT was ≤0.80. FFR ≤0.80 was the reference standard. To evaluate the influence of vessel size, the total coronary vessel lumen volume relative to left ventricular mass (volume-to-mass ratio) was calculated and compared with that of patients with stable angina. RESULTS: The study evaluated 124 nonculprit vessels from 60 patients. Accuracy, sensitivity, and specificity of FFRCT were 72%, 83%, and 66% versus 64% (p = 0.033), 93% (p = 0.15), and 49% (p < 0.001) for CTA and 72% (p = 1.00), 76% (p = 0.46), and 70% (p = 0.54) for invasive coronary angiography. Following STEMI, median volume-to-mass ratio was lower than in patients with stable angina, 53 versus 65 mm3/g (p = 0.009). In patients with volume-to-mass ratio ≥65 mm3/g (upper tertile) accuracy, sensitivity, and specificity of FFRCT were all 83% versus 56% (p = 0.009), 75% (p = 0.61), and 44% (p = 0.003) in patients with <49 mm3/g (lower tertile). CONCLUSIONS: The diagnostic performance of FFRCT for staged detection of ischemia in STEMI patients with multivessel disease is moderate. STEMI patients have a smaller vessel volume than do patients with stable angina. The diagnostic performance of FFRCT is influenced by the volume-to-mass ratio. This study does not support routine use of FFRCT in the post-STEMI setting. (Assessment of Coronary Stenoses Using Coronary CT-Angiography and Noninvasive Fractional Flow Reserve; NCT01739075).

Diagnostic performance of cardiac imaging methods to diagnose ischaemia-causing coronary artery disease when directly compared with fractional flow reserve as a reference standard: a meta-analysis.

Aims: The aim of this study was to determine the diagnostic performance of single-photon emission computed tomography (SPECT), stress echocardiography (SE), invasive coronary angiography (ICA), coronary computed tomography angiography (CCTA), fractional flow reserve (FFR) derived from CCTA (FFRCT), and cardiac magnetic resonance (MRI) imaging when directly compared with an FFR reference standard. Method and results: PubMed and Web of Knowledge were searched for investigations published between 1 January 2002 and 28 February 2015. Studies performing FFR in at least 75% of coronary vessels for the diagnosis of ischaemic coronary artery disease (CAD) were included. Twenty-three articles reporting on 3788 patients and 5323 vessels were identified. Meta-analysis was performed for pooled sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio, and summary receiver operating characteristic curves. In contrast to ICA, CCTA, and FFRCT reports, studies evaluating SPECT, SE, and MRI were largely retrospective, single-centre and with generally smaller study samples. On a per-patient basis, the sensitivity of CCTA (90%, 95% CI: 86-93), FFRCT (90%, 95% CI: 85-93), and MRI (90%, 95% CI: 75-97) were higher than for SPECT (70%, 95% CI: 59-80), SE (77%, 95% CI: 61-88), and ICA (69%, 95% CI: 65-75). The highest and lowest per-patient specificity was observed for MRI (94%, 95% CI: 79-99) and for CCTA (39%, 95% CI: 34-44), respectively. Similar specificities were noted for SPECT (78%, 95% CI: 68-87), SE (75%, 95% CI: 63-85), FFRCT (71%, 95% CI: 65-75%), and ICA (67%, 95% CI: 63-71). On a per-vessel basis, the highest sensitivity was for CCTA (pooled sensitivity, 91%: 88-93), MRI (91%: 84-95), and FFRCT (83%, 78-87), with lower sensitivities for ICA (71%, 69-74), and SPECT (57%: 49-64). Per-vessel specificity was highest for MRI (85%, 79-89), FFRCT (78%: 78-81), and SPECT (75%: 69-80), whereas ICA (66%: 64-68) and CCTA (58%: 55-61) yielded a lower specificity. Conclusions: In this meta-analysis comparing cardiac imaging methods directly to FFR, MRI had the highest performance for diagnosis of ischaemia-causing CAD, with lower performance for SPECT and SE. Anatomic methods of CCTA and ICA yielded lower specificity, with functional assessment of coronary atherosclerosis by SE, SPECT, and FFRCT improving accuracy.

Preservation of hypogastric flow and control of iliac aneurysm size in the treatment of aortoiliac aneurysms using the Nellix EndoVascular Aneurysm Sealing endograft.

OBJECTIVE: The purpose of this study was to determine the long-term effectiveness of endovascular aneurysm sealing (EVAS) in the treatment of complex aortoiliac aneurysms with preservation of hypogastric artery flow. METHODS: We reviewed all patients with abdominal aortic aneurysms (AAAs) and common iliac aneurysms (CIAs) enrolled and treated in prospective studies of EVAS using the Nellix endograft (Endologix, Irvine, Calif) at two centers from 2008 to 2014. Patients with 1 year or more of computed tomography follow-up underwent quantitative morphometric assessment by two independent vascular radiologists blinded to clinical outcome results. Hypogastric patency and CIA diameter changes over time were assessed and compared in three treatment groups: totally excluded CIA, partially excluded CIA, and untreated CIA. RESULTS: Among 125 patients with EVAS, 68 patients (mean age, 75 ± 8 years; 79% men) had both AAA (mean diameter, 55.8 ± 2.0 mm) and CIA (median diameter, 23.4; interquartile range, 21.3-27.0 mm), with bilateral CIAs in 33 patients. Treatment of 101 CIAs included complete CIA exclusion in 40 (39.6%), partial CIA exclusion in 33 (32.7%), and no CIA treatment in 28 (27.7%), with successful AAA exclusion in all patients. Internal iliac flow was preserved in all 122 hypogastric arteries that were patent before treatment (14 hypogastric arteries were occluded at baseline). During the 5-year follow-up period (median follow-up, 24.7 months; range, 11.5-61.7 months), three patients required secondary treatment with hypogastric occlusion and graft extension to the external iliac. Thus, internal iliac flow was maintained in 98% of at-risk hypogastric arteries. There were no aneurysm-related clinical events, except for the three secondary treatments. Totally excluded iliac aneurysms did not change in diameter over time (P = .85), whereas untreated CIAs enlarged at a rate of 0.16 mm/y (95% confidence interval, 0.09-0.23; P < .0001). Partially excluded CIAs enlarged at a higher rate of 0.59 mm/y (95% confidence interval, 0.47-0.71; P < .0001). Enlargement ≥3 mm occurred only in partially treated CIAs larger than 3 cm. CONCLUSIONS: EVAS was effective in treating aortoiliac aneurysms with preservation of internal iliac patency in most cases. Complete CIA exclusion prevented aneurysm enlargement over time, whereas partial exclusion did not prevent continued CIA enlargement, particularly in larger aneurysms.

Coronary Computed Tomography Angiography Derived Fractional Flow Reserve and Plaque Stress.

Fractional flow reserve (FFR) measured during invasive coronary angiography is an independent prognosticator in patients with coronary artery disease and the gold standard for decision making in coronary revascularization. The integration of computational fluid dynamics and quantitative anatomic and physiologic modeling now enables simulation of patient-specific hemodynamic parameters including blood velocity, pressure, pressure gradients, and FFR from standard acquired coronary computed tomography (CT) datasets. In this review article, we describe the potential impact on clinical practice and the science behind noninvasive coronary computed tomography (CT) angiography derived fractional flow reserve (FFRCT) as well as future applications of this technology in treatment planning and quantifying forces on atherosclerotic plaques.

Aortic neck enlargement after endovascular aneurysm repair using balloon-expandable versus self-expanding endografts.

OBJECTIVE: This study evaluated changes in aortic neck diameter after endovascular aneurysm repair (EVAR) using a balloon-expandable stent (BES) endograft compared with a commercially available self-expanding stent (SES) endograft. We hypothesized that forces applied to the aortic neck by SES endografts may induce aortic neck enlargement over time and that such enlargement may not occur in aneurysm patients treated with a device that does not use a proximal SES. METHODS: This was a retrospective quantitative computed tomography (CT) image analysis of patients treated with the Nellix (Endologix, Irvine, Calif) BES (n = 49) or the Endurant II (Medtronic, Minneapolis, Minn) SES (n = 56) endograft from 2008 to 2010. Patients with preimplant, postimplant, and at least 1-year serial CT scans underwent quantitative morphometric assessment by two independent vascular radiologists blinded to the outcome results. Changes in the infrarenal neck over time were compared with the suprarenal aorta for each patient. RESULTS: Follow-up extended to 4.8 years for the BES and to 4.6 years for the SES, with no significant difference in median follow-up time (34 months for BESs and 24 months for SESs; P = .06). There were no differences in preimplant neck diameter (25.2 ± 0.9 mm vs 25.7 ± 1.1 mm; P = .54) or length (27.7 ± 3.7 mm vs 23.6 ± 3.7 mm; P = .12) between BESs and SESs at baseline. After implantation, neck diameter increased by 1.1 ± 0.5 mm in BES patients and 2.6 ± 0.5 mm in SES patients (P = .07) compared with the preoperative diameter. At 3 years, neck diameter increased by 0.5 ± 0.9 mm in BES patients and by 3.8 ± 1.0 mm in SES patients (P = .0002) compared with the first postoperative CT scan. The annual postimplant rate of increase in the infrarenal neck diameter was fivefold greater in SES patients (1.1 ± 0.1 mm/y) than in BES patients (0.22 ± 0.04 mm/y; P < .0001). There were no significant differences in the diameter of the suprarenal aorta at baseline or at 3 years and no differences in the annual rate of change in suprarenal aortic diameter between BES and SES endografts. CONCLUSIONS: EVAR using SES endografts resulted in progressive infrarenal aortic neck enlargement, whereas EVAR using BES endografts resulted in no neck enlargement over time. These data suggest that infrarenal neck enlargement after EVAR with SES endografts is likely related to the force exerted by SES elements rather than disease progression in the infrarenal neck.