Rapid Aneurysm Expansion Research Articles

Impact of High-Risk Features and Timing of Repair for Acute Type B Aortic Dissections

The new Society for Vascular Surgery reporting standards for type B aortic dissection (TBAD) categorize clinical presentations of aortic dissection into uncomplicated, high-risk features (HRFs) and complicated groups. Although it is accepted that complicated dissections require immediate repair, the optimal timing of repair for those with HRFs has yet to be established. We aimed to identify the ideal timing of thoracic endovascular aortic repair (TEVAR) for HRFs and the outcomes associated with specific HRFs. The Vascular Quality Initiative was queried for TEVARs performed for acute and subacute TBAD with HRFs from 2014 to 2020. Rupture, malperfusion, and uncomplicated cases were excluded. HRFs were defined per the Society for Vascular Surgery guidelines as refractory hypertension, pain, and rapid aneurysm expansion or aneurysm size >40 mm. The primary outcomes were in-hospital or 30-day mortality and 1-year survival, with primary exposure variables of the interval (in days) from symptoms to repair and the number of HRFs. The secondary outcomes were spinal cord ischemia, myocardial infarction, stroke, and retrograde type A dissection. Of the 1100 patients who met the inclusion criteria, 811 had one HRF, 249 had two, and 40 had three. No significant differences were found in the primary or secondary outcomes according to the number of HRFs. Of the 1100 patients, 309 had undergone repair at 0 to 2 days, 262 at 3 to 6 days, 270 at 7 to 14 days, and 259 at ≥15 days. TEVAR performed at ≥15 days was independently associated with lower in-hospital and 30-day mortality (odds ratio, 0.38; P = .0388) and improved 1-year survival. Postoperative stroke was associated with earlier repair (0-2 days). No association was found between the timing of repair with myocardial infarction, spinal cord ischemia, retrograde type A dissection, or reintervention (Tables I and II). TEVAR for TBAD with HRFs delayed for ≥15 days from symptom onset was associated with improved survival, supporting the theory that it is best to delay TEVAR to the subacute phase. Additionally, TEVAR delayed ≥3 days was associated with a decrease in stroke. The presence of more than one HRF was not associated with worse outcomes. Because the classification of HRF is relatively new and without guidelines regarding repair, the present results highlight the risks of early intervention for patients with HRFs and suggest that these patients will benefit from at least a short stabilization period before TEVAR.Table IUnivariate analysis of impact of timing and HRFs on outcomes after TEVARVariableResultsP valueHRF1 (n = 811)2 (n = 249)3 (n = 40)NA Spinal cord ischemia42 (5.2)8 (3.2)3 (7.5).32 Myocardial infarction15 (1.9)1 (0.4)1 (2.5).17 Stroke49 (6)11 (4.4)2 (5).61 Retrograde type A dissection14 (1.7)4 (1.6)0 (0).99Interval to repair, days0-2 (n = 309)3-6 (n = 262)7-14 (n = 270)≥15 (n = 259) Spinal cord ischemia22 (7.1)8 (3.1)11 (4.1)12 (4.6).12 Myocardial infarction5 (1.6)4 (1.5)4 (1.5)4 (1.5).99 Stroke34 (11)11 (4.2)11 (4.1)6 (2.3)< .0001 Retrograde type A dissection4 (1.3)5 (1.9)3 (1.1)6 (2.3).69HRF, High-risk feature; TEVAR, thoracic endovascular aortic repair.Data presented as number (%).Boldface P values represent statistical significance. Open table in a new tab Table IIMultivariate analysis of impact of operative timing and HRFs on outcomesVariableRelated reinterventionIn-hospital/30-day mortalityOR95% CIP valueOR95% CIP valueInterval to repair 0-2 DaysRefRef 3-6 Days0.7440.38-1.455.38711.0150.499-2.063.9674 7-14 Days0.740.38-1.442.37690.4650.199-1.083.076 ≥15 Days0.5580.272-1.142.11040.380.152-0.951.0388HRFs 1RefRef 20.9840.54-1.79.9571.7250.9-3.307.1005 30.9310.21-4.121.92451.7890.465-6.876.3972CI, Confidence interval; HRF, high-risk feature; OR, odds ratio; Ref, reference.Boldface P values represent statistical significance. Open table in a new tab

Surgical Outcome of Abdominal Aortic Aneurysm Replacement in Patients with Connective Tissue Disorders under 30 Years of Age.

Objectives: Abdominal aortic aneurysm (AAA) in patients <30 years old is relatively rare. We retrospectively analyzed patients <30 years who received an AAA replacement.Materials: Among 3,003 patients who received an AAA replacement during the last 40 years, 10 patients <30 years old were retrospectively reviewed. All patients suffered from a connective tissue disease: eight from Marfan syndrome and two from Loeys–Dietz syndrome. Five patients had a history of cardiovascular surgery. Aortic pathologies were a dissection type in eight patients and a non-dissection type in two. All patients received a graft replacement of infrarenal AAA, with a bifurcated graft in six patients and a straight graft in four.Results: Except for cases that were urgent and emergent, rapid aneurysm expansion was noted in all cases. Mean AAA diameter at surgery was 46.7±9.2 mm. No hospital mortality was recorded. Eight patients required 10 additional cardiovascular surgeries: two root replacements, two total arch replacements, two descending aortic replacements, and four thoracoabdominal replacements.Conclusion: AAA replacement in patients <30 years is safe. In younger patients with a connective tissue disease, AAA should be included in the routine medical check-up, and earlier surgical indication should be considered for its rapid expansion.

Physician-modified endovascular grafts for the treatment of elective, symptomatic, or ruptured juxtarenal aortic aneurysms

To determine if a physician-modified endovascular graft (PMEG) is a safe and effective method of treating juxtarenal aortic aneurysms in patients considered to be unsuitable for open surgical repair. A retrospective, nonrandomized, single institution evaluation of the safety and efficacy of physician modification of a currently Food and Drug Administration-approved device (Zenith Flex; Cook Inc, Bloomington, Ind) to preserve branch vessels when used in the treatment of patients with elective, symptomatic, or ruptured juxtarenal aortic aneurysms. Forty-seven consecutive patients underwent fenestrated endovascular repair using PMEG over a 3-year period. Thirty-eight patients (80%) were symptomatic or had rapid aneurysm expansion. Eighty-five percent of patients were American Society of Anesthesiologist category III or IV. Eight-two fenestrations were created for 58 renal arteries, 16 superior mesenteric arteries, three celiac arteries, and the rest accessory vessels. Mean follow-up was 607 days, with a range of 425 to 1460 days. Mean contrast usage and fluoro time were 98 mL and 48 minutes. Technical success rate was 98%, and freedom from aneurysm-related death was 98%. There were six complications (13%). Three (6%) were access related, and three (6%) were procedure related and included one stroke, one case of renal failure, and one branch artery dissection. On follow-up, six patients (13%) had endoleak. There was one type 1 endoleak and five type 2 endoleaks. In-hospital and 30-day mortality was 2%, with one patient expiring due to aspiration on the ward after successful endovascular repair. Two patients died during follow-up; one at 58 days due to cessation of dialysis and one at 485 days due to stent graft migration and occlusion of the superior mesenteric artery. There were two deaths in the first year, one in the second year, and zero in the most recent year of experience. One patient with endoleak (2%) had aneurysm sac expansion at 1 year requiring secondary intervention. PMEG is a safe and effective alternative for treating patients with juxtarenal aneurysms who have no other alternatives for repair. Longer-term follow-up is needed to assess the durability of repair and potential for device-related complications.

Elective sac perfusion to reduce the risk of neurologic events following endovascular repair of thoracoabdominal aneurysms

Spinal cord ischemia (SCI) is a catastrophic complication of thoracoabdominal aortic aneurysm (TAAA) repair. This article describes our early experience with a technique for maintaining perfusion of segmental vessels (intercostals and lumbars) in the early postoperative period after endovascular repair of a TAAA, with "sac perfusion branches" added to custom-made stent grafts. These are closed 7 to 10 days after the first procedure to complete exclusion of the aneurysm. We have used this technique in 10 patients with type II TAAAs. One developed monoparesis of the right leg during a period of hypotension secondary to a cardiac event and died within 30 days. Two patients developed lower limb weakness after closure of the perfusion branches, both with full recovery. Controlled perfusion of segmental vessels with perfusion branches is feasible and may be a useful adjunct to prevent SCI, providing protection to spinal cord perfusion during the immediate postoperative period when risk of SCI is greatest.

Growth Rate and Associated Factors in Small Abdominal Aortic Aneurysms

Objective To study the growth rate and factors influencing progression of small infrarenal abdominal aortic aneurysms (AAA). Design Observational, longitudinal, prospective study. Patients and methods We followed patients with AAA <5 cm in diameter in two groups. Group I (AAA 3–3.9 cm, n=246) underwent annual ultrasound scans. Group II (AAA 4–4.9 cm, n=106) underwent 6-monthly CT scans. Results We included 352 patients (333 men and 19 women) followed for a mean of 55.2±37.4 months (6.3–199.8). The mean growth rate was significantly greater in group II (4.72±5.93 vs. 2.07±3.23 mm/year; p<0.0001). Group II had a greater percentage of patients with rapid aneurysm expansion (>4 mm/year) (36.8 vs. 13.8%; p<0.0001). The classical cardiovascular risk factors did not influence the AAA growth rate in group I. Chronic limb ischemia was associated with slower expansion (≤4 mm/year) (OR 0.47; CI 95% 0.22–0.99; p=0.045). Diabetic patients in group II had a significantly smaller mean AAA growth rate than non-diabetics (1.69±3.51 vs. 5.22±6.11 mm/year; p=0.032). Conclusions The expansion rate of small AAA increases with the AAA size. AAA with a diameter of 3–3.9 cm expand slowly, and they are very unlikely to require surgical repair in 5 years. Many 4–4.9 cm AAA can be expected to reach a surgical size in the first 2 years of follow-up. Chronic limb ischemia and diabetes are associated with reduced aneurysm growth rates.

Abdominal aortic aneurysm in liver transplant recipients.

To analyze the incidence, clinical features, expansion rate of, and clinical approach to abdominal aortic aneurysm in patients who had undergone orthotopic liver transplantation. To our knowledge, this is the first report on this issue in liver transplant recipients. Among 172 patients undergoing 185 liver transplantations at our institution over the last 10-year period, we identified three patients (1.7%) with infrarenal aortic aneurysm. They had all undergone routine pre-liver transplant ultrasonography screening for aortic aneurysm. All three patients were symptom free at the time of the discovery of a mild infrarenal abdominal enlargement before ( n=2) and after liver transplantation ( n=1), and were closely monitored by ultrasonography in the follow-up period (3.1-4.3 years). The mean aneurysm expansion rate was 0.73 cm/year. All patients underwent aneurysm repair after their aneurysm expanded significantly under observation, with a mean diameter of 5.1 cm at the time of repair. All three patients are alive and well (median follow-up: 19 months). Our data suggest that careful ultrasonographic surveillance is warranted in any liver transplant recipient, because of the apparent propensity for a more rapid aneurysm expansion and potentially aggressive course than in the untransplanted population. Early repair of the infrarenal aneurysm is recommended in transplant recipients, given that excellent perioperative and late outcomes can be achieved.

Aneurysm Expansion and Retroperitoneal Hematoma After Thrombolysis for Stent-Graft Limb Occlusion Caused by Distal Endograft Migration

PURPOSE: To describe a complication of thrombolytic therapy used to treat graft limb occlusion precipitated by distal migration and kinking of an abdominal aortic stent-graft. CASE REPORT: A 5.5-cm abdominal aortic aneurysm (AAA) in a 66-year-old woman was treated with Vanguard bifurcated stent-graft. At the 1-year follow-up, she complained of left leg claudication. Computed tomography (CT) showed a 36% reduction in maximum AAA diameter, but the stent-graft had migrated distally approximately 5 mm, and the left graft limb was occluded. Thrombolysis was initiated, but after approximately 8 hours, abdominal pain began. Emergent CT scanning revealed rapid aneurysm expansion and a retroperitoneal hematoma. Thrombolytic treatment was stopped; transfusions and thrombogenic drugs were given to restore hemodynamic stability. The aneurysm began to decrease in size. The occluded graft limb had been reopened by the lytic therapy, uncovering a stenosis in the native artery distal to the graft limb. Stent placement restored outflow. The retroperitoneal hematoma resolved over time, and the aneurysm sac shrank to its prelytic diameter. The patient is well with a functioning endograft 18 months after the occlusion (30 months after stent-grafting). CONCLUSIONS: Caution must be taken when using thrombolysis in patients with endovascular aortic grafts because unexpected bleeding complications might arise. Thrombectomy, femorofemoral bypass, or stent or stent-graft extensions might be safer alternatives for treating occluded stent-graft limbs. (Less)

Thoracoabdominal Aortic Aneurysm Repair in Cardiac Transplant Recipients

We present here two cases of asymptomatic thoracoabdominal aortic aneurysms that were successfully operated on in heart transplant patients 8 and 23 months after transplantation. Thoracoabdominal aortic aneurysm was present prior to transplantation in one patient. In the other patient only the abdominal aortic aneurysm was found before transplantation. Indications for transplantation were ischemic and valvular cardiomyopathy. Surgical aortic aneurysm repair was performed with the standard technique. Both patients were discharged from the hospital. The possible contributing factors to the development and enlargement of aortic aneurysms and perioperative assessment are also discussed. Radiologic surveillance is warranted in any heart transplant recipient with abdominal or thoracoabdominal aortic aneurysms because of the more rapid aneurysm expansion.

Abdominal aortic aneurysm in the patient undergoing cardiac transplantation

In the past 3 years at our institution 130 patients have undergone cardiac transplantation for ischemic cardiomyopathy in 49 (38%), idiopathic cardiomyopathy in 42 (32%), viral cardiomyopathy in 9 (6.9%), pulmonary hypertension in 8 (6%), and graft atherosclerosis in 2 (1.5%). Routine preoperative abdominal ultrasonography was performed on 98 (75%) of these patients with specific visualization of the abdominal aorta in 93 (95%). Abdominal aortic aneurysms (all infrarenal) were found before operation in four patients and only in the subgroup undergoing transplantation for ischemic heart disease (10.5%). They measured 3.4, 4.5, 3.6, and 3.8 cm before transplantation. Periodic evaluation by ultrasonography was carried out after transplantation during the 3-year period of this study. One aneurysm that was initially 3.6 cm increased to 4.0 cm and ruptured 2 months after transplantation. The patient died despite emergent surgery. Aneurysms in three patients who demonstrated rapid aneurysm expansion after transplantation were successfully repaired at 5, 20, and 33 months after transplantation when the lesions reached 5.5, 5.9, and 4.8 cm. A fifth patient with an initially normal (1.5 cm) aorta developed a symptomatic aneurysm of 4.1 cm, which was repaired uneventfully. The average expansion rate of these aneurysms after transplantation was 0.74 ± 0.15 cm/year. This experience suggests that aneurysms are limited to patients undergoing transplantation for ischemic heart disease. Ultrasound examination may be appropriate for preoperative screening. Careful aortic surveillance after transplantation is important in patients having transplantation for ischemic cardiomyopathy because of the apparent rapid expansion rate compared to aneurysms in the population not receiving transplants.

Abdominal aortic aneurysm in the patient undergoing cardiac transplantation

In the past 3 years at our institution 130 patients have undergone cardiac transplantation for ischemic cardiomyopathy in 49 (38%), idiopathic cardiomyopathy in 42 (32%), viral cardiomyopathy in 9 (6.9%), pulmonary hypertension in 8 (6%), and graft atherosclerosis in 2 (1.5%). Routine preoperative abdominal ultrasonography was performed on 98 (75%) of these patients with specific visualization of the abdominal aorta in 93 (95%). Abdominal aortic aneurysms (all infrarenal) were found before operation in four patients and only in the subgroup undergoing transplantation for ischemic heart disease (10.5%). They measured 3.4, 4.5, 3.6, and 3.8 cm before transplantation. Periodic evaluation by ultrasonography was carried out after transplantation during the 3-year period of this study. One aneurysm that was initially 3.6 cm increased to 4.0 cm and ruptured 2 months after transplantation. The patient died despite emergent surgery. Aneurysms in three patients who demonstrated rapid aneurysm expansion after transplantation were successfully repaired at 5, 20, and 33 months after transplantation when the lesions reached 5.5, 5.9, and 4.8 cm. A fifth patient with an initially normal (1.5 cm) aorta developed a symptomatic aneurysm of 4.1 cm, which was repaired uneventfully. The average expansion rate of these aneurysms after transplantation was 0.74 +/- 0.15 cm/year. This experience suggests that aneurysms are limited to patients undergoing transplantation for ischemic heart disease. Ultrasound examination may be appropriate for preoperative screening. Careful aortic surveillance after transplantation is important in patients having transplantation for ischemic cardiomyopathy because of the apparent rapid expansion rate compared to aneurysms in the population not receiving transplants.

Variables that affect the expansion rate and outcome of small abdominal aortic aneurysms

Seventy-three patients with small (<6 cm in diameter) abdominal aortic aneurysms (AAAs) were selected for nonoperative management and followed up with sequential ultrasound size measurements. Fifty-four men and 19 women, 51 to 89 years of age (mean 70 years), had an initial mean AAA size of 4.1 cm (anteroposterior) × 4.3 cm (lateral) diameter, with a calculated elliptic cross-sectional area of 14.3 cm2. After a mean of 37 months of follow-up, AAA area increased at a mean rate of 20% per year (3 cm2 yr; 0.4 to 0.5 cm/yr diameter). Expansion rate was not affected by initial aneurysm size. During follow-up, only 3 patients (4%) required urgent operation (1 died), 26 patients (36%) died of non-AAA causes, and 26 patients (36%) underwent elective AAA repair because of progressive size increase (1 died). Elective operations were performed at the rate of 10% per year, when mean AAA size had increased to 22 cm2 (5.1 cm in diameter). Multiple regression analysis of clinical parameters available at presentation indicated that subsequent elective AAA repair was predicted by younger age at diagnosis and larger initial aneurysm size. As anticipated, patients who underwent surgery had more rapid aneurysm expansion (5.3 cm2/yr) compared with patients who did not undergo surgery (1.6 cm2/yr; p < 0.05). This difference was caused by more rapid expansion during later follow-up intervals among patients selected for operation and was not predicted by the change in aneurysm size observed during initial ultrasonographic follow-up. Final aneurysm size was predicted by initial size, duration of follow-up, and both systolic and diastolic pressure. Larger initial size, longer follow-up, and widened pulse pressure predicted larger aneurysm size. Individual AAA expansion rates, however, were variable over time and could not be predicted by any parameters tested. Patients with small AAAs may be safely followed up if their pulse pressure is controlled and elective aneurysm repair is performed when aneurysm diameter reaches 5 to 6 cm based on sequential ultrasound size measurements.

Anaesthesia for abdominal aortic surgery--a review (Part II).

Patients presenting for abdominal aortic surgery have a high incidence of vascular disease elsewhere, manifested primarily by hypertension, coronary and cerebrovascular disease, as well as co-existing respiratory, renal and metabolic disorders. Routine clinical assessment, electrocardiogram, chest roentgenograms, resting and exercise radionuclide ventriculography and echocardiography, dipyrdiamole-thallium scanning are all designed to assess the functional status of the myocardium and to detect the presence of significant coronary artery disease. Patients with no abnormalities on physical examination, routine evaluation and no redistribution on dipyridamole-thallium scanning should proceed to surgery with the expectation of very low perioperative cardiac risk. Patients with evidence of coronary artery disease and significant redistribution on dipyridamole-thallium scan should undergo coronary angiography and possible myocardial revascularization before definitive aortic vascular surgery. For high cardiac risk patients with no bypassable lesions presenting for abdominal aortic aneurysm resection a conservative policy of serial three monthly ultrasound or CT assessment may be adopted, with selective resection for rapid aneurysm expansion or symptom development. A variety of extra-anatomical and angioplastic techniques is available for similar high cardiac risk patients with aortoiliac occlusive disease. The haemodynamic consequences of aortic cross-clamping, especially in aneurysm patients, include a significant reduction in stroke volume, cardiac index, and myocardial oxygen consumption with an increased systemic vascular resistance. Patients with coronary artery disease may respond to aortic cross-clamping by increasing pulmonary capillary wedge pressure and by demonstrating ECG evidence of myocardial ischaemia. Pulmonary artery catheterization is especially indicated in patients with a history of previous myocardial infarction, angina or signs of cardiac failure and in patients with evidence of diminished ejection fraction, abnormal ventricular wall motion or myocardial redistribution on preoperative scanning. The more widespread application of intraoperative transoesophageal two-dimensional echocardiography and radionuclide cardiography monitoring techniques into anaesthetic practice will enable measurement of left ventricular dimensions, myocardial performance and wall motion. Suggested guidelines for anaesthetic management are presented in Table VI. A combined opiate-oxygen-volatile anaesthetic agent technique will best ensure a hypodynamic circulation with preservation of myocardial oxygenation.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment Options for Aneurysms in High-Risk Patients

The increasing prevalence of aneurysms in an aging population bears with it increasing numbers of patients who are less than optimal candidates for resection. It is likely that the majority of such patients can undergo standard resection, either by referral to a center where the management of the elderly chronically ill is commonplace or by providing intensive preoperative metabolic, cardiac, pulmonary, and nutritional resuscitation. Such preoperative preparation might well include coronary revascularization or carotid endarterectomy. For the occasional patient in whom medical comorbidity is advanced and fixed, or in whom rapid aneurysm expansion or worsening symptoms mandate immediate management, yet operative risk for standard aneurysm resection seems inordinately high, several nonresective options have been identified and tested. Among these options, aneurysm exclusion appears to have significantly better results (in terms of lower rates of operative mortality and subsequent aneurysm rupture) than distal aneurysm ligature. A more recent technique, aneurysm bypass, may have potential but has not been tested for a long enough period, or by an adequate number of surgeons, to have established itself as a nonresective option. Clinical judgment, technical expertise, and a willingness to seek assistance and consultation remain the hallmarks of the optimal management of the patient with an abdominal aortic aneurysm.