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Manish Mehta

Publications and source records attributed to Manish Mehta.

31 records · Page 2Linked to original sources
PubMed2003

Eversion carotid endarterectomy: a technical alternative that may obviate patch closure in women.

PURPOSE: Recurrent carotid stenosis following standard longitudinal carotid endarterectomy (s- CEA), with and without patch angioplasty, effects the durability of the procedure and can lead to reintervention. The purpose of this study is to evaluate the incidence of restenosis following eversion carotid endarterectomy (e-CEA) in women. METHODS: The records of all patients undergoing elective carotid endarterectomy (CEA) for symptomatic and asymptomatic high-grade carotid stenosis over a 5-year period from July 1994 to June 1999 were reviewed. Eversion endarterectomy was performed preferentially under regional anesthesia in awake patients. Postoperatively, patients were routinely evaluated by duplex scans at 3 months, 6 months, 12 months, and yearly thereafter. Hemodynamically significant restenosis (>70%) via duplex scans was confirmed by standard or magnetic resonance angiography. Student's t-test and Chi square analysis were used to assess statistical significance and assumed for P<0.05. RESULTS: Over this 5-year period, 3429 eversion carotid endarterectomies were done for symptomatic (female: 375, male: 573) and asymptomatic (female: 1091, male: 1390) high grade carotid stenosis. In the postoperative period 18 (0.9%) male and 12 (0.8%) female patients developed a permanent stroke (P = NS). Operative mortality was 0.6% (n = 12) in males and 0.5% (n = 8) in females (P = NS). Cranial nerve injuries, wound infections, and neck hematoma occurred in 7 (0.4%), 2 (0.1%), and 26 (1.3%) male and in 3 (0.2%), 3 (0.2%), and 15 (1.0%) female patients, respectively. Recurrent carotid stenosis greater than 70% via duplex scan (PSV >125 cm/s and EDV >100 cm/s) developed in 12 (1.0%) males and 15 (1.5%) females (P = NS). CONCLUSION: The eversion technique for CEA requires both the transection and anastomosis of the internal carotid artery at the carotid bulb, and appears to result in a low incidence of restenosis in women. This is a straightforward technique and obviates the need for primary closure of distal smaller caliber internal carotid artery that can lead to narrowing, and the use of patch closure that has its attendant risks.

Adult↗
PubMed2003

Should ruptured abdominal aortic aneurysms be repaired in the octogenarian?

PURPOSE: Several investigators have suggested a dismal prognosis of ruptured abdominal aortic aneurysm (rAAA) repair in the elderly. The purpose of this study is to evaluate the morbidity and mortality of rAAA repair in octogenarians and compare it to that of a younger population. METHODS: From 1980 to 2000, all patients undergoing emergent rAAA repair were divided into two groups based on their age; Group I: age <80, Group II: > or =80 years. Outcomes were evaluated based on a Chi-square test and a P-value <0.05 indicated statistical significance. RESULTS: Over a 20-year period, 323 patients underwent rAAA repair through a left retroperitoneal (74%) or standard transperitoneal (26%) approach. In Group I (age <80 years) and II (> or =80 years), the overall 30-day mortality was 25 and 41% (P<0.05), respectively. Furthermore, the elderly population had a higher incidence of death due to myocardial infarction (15 vs. 7%), as well as non-fatal cardiac and cerebrovascular events (17 vs. 4%) when compared to the younger patients. CONCLUSION: Although the elderly patients have an increased risk of having cardiac and cerebrovascular events in the postoperative period, the treatment of rAAAs in these patients should not be any different than that of a younger population. The left retroperitoneal approach is feasible and beneficial for rAAA repair and is associated with a limited morbidity and mortality.

Age Factors↗
PubMed2003

Carotid-carotid crossover bypass: is it a durable procedure?

PURPOSE: Reconstruction of a diseased common carotid artery may necessitate direct repair via aortic artery-based revascularization. However, carotid-carotid artery crossover grafting is an alternative extra-anatomic option that obviates the need for median sternotomy. We analyzed our results with carotid-carotid artery crossover bypass surgery. METHODS: Data were analyzed for all patients undergoing carotid-carotid crossover bypass surgery from 1995 to 2000. Data on patient demographics, indications for surgery, perioperative morbidity and mortality, and graft patency were retrieved from a vascular surgery data base and hospital records. Stroke-free survival and graft patency were determined with life table methods. RESULTS: Over 5 years, 24 carotid-carotid artery crossover bypass procedures were performed to treat both symptomatic (n = 19, 79%) and asymptomatic (n = 5, 17%) disease. Nine procedures (38%) were performed in men, 3 (13%) in patients with diabetes, 12 (50%) in active smokers, and 2 in patients with a history of Takayasu arteritis. Patient mean age was 63 years (range, 38-79 years). Twenty-three patients (96%) received polytetrafluoroethylene conduit grafts, and the remaining patients received vein grafts. Ten (42%) patients underwent concomitant endarterectomy. There were no perioperative deaths. One patient (4%) had asymptomatic early occlusion, one had transient neurologic deficit (4%), one (4%) required additional surgery because of bleeding, and one (4%) had a perioperative cerebrovascular accident (stroke). Three (17%) asymptomatic late occlusions were identified at 11, 57, and 64 months, respectively. Mean follow-up was 30 months (range, 1-70 months). Primary patency was 88%, and secondary patency was 92% at 3 years. Stroke-free survival was 94% at 4 years. CONCLUSION: Carotid-carotid artery crossover bypass surgery is a safe and durable procedure. Its use precludes the need for median sternotomy and provides acceptable stroke-free survival.

Adult↗
PubMed2003

Significance of endotension, endoleak, and aneurysm pulsatility after endovascular repair.

OBJECTIVE: The lack of aneurysm pulsatility after endovascular aneurysm repair (EVAR) is deemed by some an important guide to the effectiveness of exclusion. However, factors that contribute to aneurysm pulsatility after EVAR have not been elucidated. This study quantitatively analyzed the effects of systemic pressure, aneurysm sac pressure, endoleak, branch outflow from aneurysm sac, and intra-sac thrombus on aneurysm pulsatility after EVAR. METHODS: In an ex vivo model, an artificial aneurysm sac was incorporated within a mock circulation comprised of rubber tubing and a pulsatile pump. The aneurysm sac was then completely excluded from the circulatory circuit with two types of stent-grafts, ie, supported and unsupported, and heparinized canine blood was circulated. Systemic circulation and aneurysm sac pressure was recorded in the absence and presence of endoleaks, and simulated open and closed lumbar branch outflow from the aneurysm sac. The aneurysm sac was then filled with organized human thrombus, and all pressure measurements were repeated. Two observers blinded to the above-mentioned variables independently evaluated aneurysm sac pulsatility with palpation in five separate experiments. Analysis of variance was performed, with significance accepted at P =.05. RESULTS: Systemic pressure was simulated in the artificial circulation to range from 100/60 to 180/60 mm Hg. Regardless of the simulated lumbar branch outflow from the aneurysm, sac pressure was directly related to the presence of endoleak (P <.001). Aneurysm sac pulsatility was present only when the lumbar branch outflow was patent and not dependent on sac pressures. Aneurysm sac thrombosis or type of stent-graft did not influence sac pressure and pulsatility. CONCLUSIONS: In this model, after EVAR pulsatility depends on aneurysm sac outflow, regardless of endoleak, sac thrombosis, sac pressure, or stent-graft. Furthermore, persistent pulsatility does not predict systemic intra-sac pressure, nor does lack of pulsatility reflect freedom of the aneurysm sac from systemic pressurization. This ex vivo model suggests that aneurysm pulsatility is an unreliable guide for predicting aneurysm sac pressurization after EVAR. Other diagnostic methods must be used to assess successful aneurysm exclusion.

Anastomosis, Surgical↗
PubMed2003

Does subintimal angioplasty have a role in the treatment of severe lower extremity ischemia?

OBJECTIVE: Subintimal angioplasty (SIA) has been advocated to treat long segment lower extremity arterial occlusions, but many question its value. We evaluated the role of SIA in a group of patients with severe lower extremity arterial occlusive disease. METHODS: During a 2.5-year period, 39 patients with arterial occlusions (median length, 8 cm; range, 2 to 31 cm) were treated on an intention-to-treat basis with SIA. Twenty-five patients had gangrene, five had rest pain, and nine had disabling (<one block) claudication. There were 24 superficial femoral, two superficial-femoral-popliteal, four popliteal, two popliteal-tibial, five tibial, and two external iliac artery lesions. With fluoroscopic guidance, via a prograde common femoral artery puncture (n = 29) or a contralateral common femoral artery puncture (n = 9), a subintimal dissection plane was created across the occlusion with a standard guidewire and catheter. The arterial lumen was reentered distal to the occlusion, and the recanalized segment balloon was dilated. All patients were followed prospectively with arterial duplex scan. RESULTS: SIA was technically successful in 34 of 39 patients (87%). All five failures were from an inability to reenter the patent lumen distally. These five patients underwent successful bypasses that in no case were more distal than would have been required before SIA. In the 34 technically successful SIAs, pain completely resolved (14/14) and areas of gangrene (21/25) healed. The cumulative patency rate in patients who underwent successful SIA was 74% +/- 10% at 12 months. The mean increase in ankle-brachial index after SIA was 0.34 (range, 0.1 to 0.69). There were two distal embolic events, successfully treated surgically (n = 1) or with catheter-directed techniques (n = 1). Three patients underwent subsequent bypass, and the remaining five patients remain asymptomatic. CONCLUSION: SIA is feasible and can be effective in some patients with lower extremity arterial occlusions and threatened limbs. These results, plus SIA's many advantages, support an increasing role for it in the treatment of lower extremity arterial occlusive disease.

Aged↗
PubMed2003

Surgical treatment of internal carotid artery occlusion.

PURPOSE: Nonoperative treatment of recent internal carotid artery (ICA) occlusion is associated with increased recurrent stroke rates. We analyzed our results of carotid endarterectomy (CEA) for treatment of symptomatic recent ICA occlusion to evaluate its feasibility, safety, and outcomes. METHODS: From 1990 to 2002, all patients with transient ischemic attack (TIA), amaurosis fugax, and minor stroke underwent duplex ultrasound (US) scanning and arteriography to confirm the diagnosis of ICA occlusion. Within 2 weeks of symptom onset, patients underwent operative exploration with attempted CEA. ICA occlusion was detected at preoperative angiography and confirmed at surgery. Patients with extensive ICA plaque not amenable to endarterectomy underwent external CEA with ICA ligation. RESULTS: Over 12 years, 87 patients with symptomatic ICA occlusion underwent 90 operations for ICA exploration. In 30 patients (18 men, 12 women) with TIA (45%), amaurosis fugax (19%), or minor stroke (36%), CEA to treat ICA occlusion was technically successful. There was 1 postoperative stroke, 2 asymptomatic internal carotid occlusions, and no restenoses (mean follow-up, 26 months; range, 1-93 months). In 57 patients (37 men, 20 women) with TIA (41%), amaurosis fugax (27%), or stroke (32%) in whom CEA was unsuccessful, external CEA was performed. In this group there were no postoperative strokes, 2 asymptomatic external carotid artery occlusions, and 1 restenosis (>70%) (mean follow-up, 22 months; range, 1-73 months). There were no late strokes in either group. CONCLUSION: Operative exploration and endarterectomy to treat symptomatic ICA occlusion is feasible and safe. Patients with symptomatic ICA occlusion should be considered candidates for CEA.

Adult↗
PubMed2002

Carotid endarterectomy in the elderly: does gender effect outcome?

OBJECTIVES: Carotid endarterectomy (CEA) has a positive effect on stroke free survival in patients with either symptomatic or asymptomatic severe carotid bifurcation stenosis. However, most trials have excluded octogenarians. In addition, concerns have arisen regarding the benefits of CEA in the elderly population, especially in women. In this study, we performed an outcome analysis in patients undergoing CEA comparing those eighty and older to their younger counterparts. Additionally, we evaluated the elderly group based on gender. METHODS: Over the past 10 years, all patients undergoing CEA for asymptomatic and symptomatic carotid disease have been entered into our vascular surgery registry. Demographics, indications for operative intervention, outcomes and survival of patients who had undergone CEA were reviewed. Procedures were preferentially performed under regional anesthesia with selective shunting. Chi square analysis was used to assess significance and assumed for P<0.05. RESULTS: Over the last 10 years, 125 carotid endarterectomies were performed in 125 patients eighty years of age or older. Fifty-six were male and 69 were female. Mean age was 83 (range: 80-97). Asymptomatic disease was identified in 28 of the male patients (50%) and 44 of the female patients (64%). There were no deaths and a permanent neurological deficit occurred in one female patient. There was no difference in thirty-day morbidity or mortality in female patients compared to males. CONCLUSIONS: These observations suggest that CEA can be safely performed in selected elderly patients with asymptomatic or symptomatic carotid artery stenosis. Furthermore, women over 80 may expect equally optimistic results as their male counterparts.

Age Factors↗
PubMed2002

Choice of material for internal carotid artery bypass grafting: vein or prosthetic? Analysis of 44 procedures.

PURPOSE: Although infrequent, reconstruction of the internal carotid artery due to recurrent or extensive disease, tumor, or difficulty in completing the endarterectomy, may be necessary. Few studies evaluate the type of material used as conduit in regard to outcome. In this report we detail our results using both prosthetic and vein bypass of the internal carotid artery for atherosclerotic bifurcation stenosis. METHODS AND MATERIALS: All patients undergoing carotid artery reconstruction over the last 10 years were retrieved from our vascular registry. Those patients requiring bypass of the internal carotid artery were included. Demographics, indication, complications, and long term follow-up were reviewed. Chi square and log rank analysis was used to compare bypass with PTFE to those with vein as conduit. RESULTS: Over the last 10 years, 44 reconstructions of the internal carotid artery were performed in 41 patients. Twenty-two procedures used prosthetic and 22 used vein. Asymptomatic carotid artery occlusive disease was identified in 14 of the 22 procedures with PTFE, and in 10 of 22 patients with vein. There was no operative mortality in the prosthetic group, and one patient died of a stroke (4.5%) in the vein graft group. There were no strokes or occlusions in the PTFE group. Two permanent neurologic deficits (9%) and one occlusion occurred in the vein bypass group. In follow-up, there have been no late occlusions in the PTFE group, and three in the vein group. CONCLUSION: While endarterectomy is the procedure of choice in carotid bifurcation stenosis, internal carotid artery bypass can be performed with reasonable outcomes whenever necessary. Prosthetic reconstruction of the internal carotid artery had acceptable results that was comparable to vein graft reconstruction.

Aged↗
PubMed2002

Nonoperative management with selective delayed surgery for large abdominal aortic aneurysms in patients at high risk.

OBJECTIVE: An accepted fact is that abdominal aortic aneurysms (AAAs) larger than 5.5 cm should undergo elective repair. However, subsets of these patients have serious comorbid conditions, which greatly increase operative risk. This study evaluated the outcomes of periods of protracted nonoperative observational management with selective delayed surgery in patients at high risk with large infrarenal and pararenal AAAs. METHODS: Among 226 patients with AAAs more than 5.5 cm, we selected 72 with AAAs from 5.6 to 12.0 cm (mean, 7.0 cm) for periods of nonoperative management because of their prohibitive surgical risks. Comorbid factors included a low ejection fraction of 15% to 34% (mean, 22%) in 18 patients, 1 second forced expiratory volume less than 50% (mean, 38%) in 25, prior laparotomy in 10, and morbid obesity in 22. Follow-up examination was complete in the 72 patients for the 6 to 76 months (mean, 23 months) that they underwent nonoperative treatment. Fifty-three patients ultimately underwent operation because of AAA enlargement or onset of symptoms after 6 to 72 months (mean, 19 months) of nonoperative treatment. RESULTS: Of the 72 selected patients, 54 (75%) are living and 18 (25%) are dead. Seven patients who underwent only nonoperative treatment presently survive after 28 to 76 months (mean, 48 months). Of the 18 deaths, AAA rupture occurred in only three patients (4%) who were observed for 12, 31, and 72 months before rupture. Nine other deaths (13%) occurred after 6 to 72 months from comorbidities unrelated to the AAA. Six of the 53 patients who underwent delayed operation died within 30 days of operation (11% mortality rate). The mortality rate for the 154 good-risk patients with an AAA who underwent prompt open or endovascular repair was 2.2%. CONCLUSION: These data indicate that some patients with large AAAs and serious comorbidities are acceptably managed for long periods (6 to 76 months) with nonoperative means. Substantial delays of 12 to 76 months resulted in an AAA rupture rate of only 4%, and 13% of these patients (nine of 72) died of comorbidities unrelated to AAA rupture or surgery. Mortality rate in this group of patients, when operated, was 11% (six of 53). These findings support the selective use of nonoperative management in some patients with large AAAs and serious comorbidities.

Aged↗
PubMed2002

Composite sequential arterial reconstruction for limb salvage.

OBJECTIVE: Autogenous vein is the conduit of choice in patients presenting for infrainguinal arterial reconstruction. Venous conduit may be limited because of inadequacy or prior utilization. Our group and others use prosthetics to maximize limb salvage with moderate results. However, in cases where patients present with an isolated popliteal segment that may extend below the knee, we have performed prosthetic bypasses to this above-knee segment and then used a venous reconstruction from the native arterial circulation to a more distal outflow tract. In this report, we will analyze our results using this type of reconstruction in patients who present for limb salvage with no all-autogenous option. METHOD: From 1992 to 2000, 27 patients presented for limb salvage with an isolated popliteal artery and inadequate vein for continuous bypass. There were 106 patients in this period without an isolated popliteal segment or adequate vein who underwent prosthetic bypass with distal vein cuff or arteriovenous fistula. The vascular registry and patient charts were reviewed for indication, demographics, and type of composite reconstruction. Outcomes were calculated with use of life table methods and compared by log rank analysis. RESULTS: Demographics revealed 16 (59%) men, 16 (59%) patients with diabetes, and 4 (15%) smokers with a mean age of 71 years (range, 51-87 years). The venous reconstructions had the inflow taken from the distal native popliteal artery in 26 (above knee in 8 and below knee in 18) and the peroneal artery in one. The outflow involved the below-knee popliteal in one (4%), a tibial in 23 (85%), and the dorsalis pedis artery in 3 (11%). Morbidity included bleeding (4%), wound infection (4%), and limb loss (4%). Mortality occurred in one patient (4%), and no revisions were required in follow-up. Six late failures were identified, one of which resulted in amputation. Primary patency and limb salvage were 80% and 88% at 1 year, respectively. For comparison, our results using prosthetic with vein cuff had a 1-year primary patency of 52% and limb salvage of 92% (P = NS), whereas prosthetic with an arteriovenous fistula was 73% and 84%, respectively (P = NS). CONCLUSIONS: Composite sequential reconstruction using an isolated popliteal segment as inflow for the distal reconstruction is an acceptable option in patients presenting for limb salvage reconstruction with limited venous conduit. This type of reconstruction, when available, may be a better option than pure prosthetic with or without a vein cuff or arteriovenous fistula.

Adult↗
PubMed2002

Combined coronary artery bypass with carotid endarterectomy: do women have worse outcomes?

OBJECTIVE: Women undergoing coronary artery bypass grafting (CABG) have higher mortality and morbidity in numerous studies. Although controversial, similar results have been seen in women undergoing carotid endarterectomy. We examined the results of combined eversion CEA/CABG by one group to analyze if the outcome is different between men and women in this setting. METHOD: The records of all patients undergoing combined eversion CEA/CABG were reviewed from our vascular registry between January 1992 and January 2001. Indications, demographics, morbidity, and mortality were retrieved. These results were compared on the basis of gender as well as to patients undergoing CEA alone. Significance was assessed using Theta(2) analysis. RESULTS: There were 563 combined eversion CEA/CABG procedures performed over the 9-year study period: 324 in men and 239 in women. Asymptomatic >70% stenosis was seen in 275 (85%) male patients and 215 (90%) female patients (P = not significant [NS]). Stroke was found in four men vs three women (1.2% vs 1.3%, P = NS), whereas death occurred in 13 men and five women (4.0% vs 2.1%, P = NS). Thirty-day stroke/mortality was 4.9% in men vs 3.3% in women (P = NS). During the same period, patients undergoing CEA alone were subject to a stroke-mortality rate of 1.6% in men and 1.2% in women (P = NS). CONCLUSION: This series demonstrated no difference in outcome among patients undergoing combined eversion CEA/CABG procedures on the basis of gender. Although the results demonstrate a significantly higher mortality and morbidity in patients undergoing combined procedures when compared to carotid surgery alone, the combined procedures can be performed safely in both genders. The large number of asymptomatic patients in both the combined and solo procedures may have positively influenced these results.

Adult↗
PubMedDate not supplied

Outcome of concomitant renal artery reconstructions in patients with aortic aneurysm and occlusive disease.

The question remains as to whether patients presenting with aortoiliac occlusive disease (AIOD) or abdominal aortic aneurysms (AAAs) have similar outcomes when concomitant renal artery reconstructions are performed. In this study, we analyzed our experience with simultaneous aortic and renal reconstructions using a retroperitoneal approach. Over a 5-year period, all patients with either AAAs > 5 cm or symptomatic AIOD who were found to have high-grade renal artery stenosis and who underwent aortic reconstructions with concomitant renal revascularization were analyzed through our vascular surgery registry. Morbidity and mortality were quantitatively evaluated. Data were analyzed using the chi-square test. A total of 1,133 patients with AAA (n = 832) and AIOD (n = 301) underwent aortic reconstructions. Two hundred thirty-one patients had 283 concomitant renal revascularizations, including bypass, reimplantation, and endarterectomy, for high-grade (> 70%) renal artery stenosis via a left retroperitoneal approach. The mortality rate of AAA repair with and without renal revascularization was 2.3% (4/178) and 1.5% (10/654), respectively, and that of aortobifemoral bypass for AIOD with and without renal revascularization was 5.7% (3/53) and 2.8% (7/248), respectively. Of the 7 deaths in patients requiring aortic and renal reconstructions, 4 occurred in patients with bilateral renal revascularization. Transient renal insufficiency, ischemic colitis, and cardiopulmonary failure occurred in 5.6%, 2.2%, and 9.6% of patients with AAA repair and in 5.7%, 0%, and 9.4% of patients with AIOD. Two patients developed acute occlusion of their renal bypasses; one was successfully revised, whereas the other led to a nephrectomy. In patients with AAAs, AIOD, and high-grade renal artery stenosis, simultaneous aortic and renal reconstructions can be performed through a retroperitoneal approach with a limited and acceptable mortality. With concomitant renal and aortic procedures, patients with AIOD have a higher mortality when compared with those with AAAs, although this difference is not statistically significant.

Adolescent↗