An analysis of the outcomes of a decade of experience with lower extremity revascularization including limb salvage, lengths of stay, and safety

Comparative effectiveness study of self-directed walking exercise, lower extremity revascularization, and functional decline in peripheral artery disease

OBJECTIVE

Among individuals with peripheral artery disease (PAD), we compared annual change in 6-minute walk performance between participants who neither underwent lower extremity revascularization nor walked for exercise (group 1, reference), those who walked regularly for exercise (group 2), and those who underwent lower extremity revascularization (group 3).

METHODS

Participants were recruited from Chicago-area vascular laboratories and followed annually. Change in 6-minute walk was calculated beginning at the study visit preceding lower extremity revascularization or exercise behavior and continuing for 1 additional year after the therapy was reported. Results are adjusted for age, sex, race, comorbidities, and other confounders.

RESULTS

Of 348 PAD participants, 43 underwent revascularization during median follow-up of 84 months. Adjusted annual declines in 6-minute walk were -96.6 feet/year for group 1, -49.9 feet/year for group 2, and -32.6 feet/year for group 3 (P < .001). Forty-one percent of revascularizations were not associated with ankle-brachial index (ABI) improvement. When group 3 was limited to participants with ABI improvement ≥0.15 after revascularization, annual adjusted changes in 6-minute walk were -97.7 feet/year for group 1, -46.5 feet/year for group 2, and +68.1 feet/year for group 3 (P < .001). When group 3 was limited to participants without ABI improvement ≥0.15 after revascularization, annual adjusted changes in 6-minute walk were -99.2 feet/year for group 1, -48.0 feet/year for group 2, and -61.7 feet/year for group 3 (P < .001).

CONCLUSIONS

A large proportion of PAD participants did not have ABI improvement of at least 0.15 at follow-up study visit after revascularization. The benefits of lower extremity revascularization in patients with PAD appear closely tied to improvements in the ABI after revascularization.

Application of Porter’s Five Forces Model and generic strategies for vascular surgery: should be stuck in the middle?

There are many stakeholders in the vascular marketplace from clinicians to hospitals, third party payers, medical device manufacturers and the government. Economic stress, threats of policy reform and changing health-care delivery are adding to the challenges faced by vascular surgeons. Use of Porter's Five Forces analysis to identify the sources of competition, the strength and likelihood of that competition existing, and barriers to competition that affect vascular surgery will help our specialty understand both the strength of our current competition and the strength of a position that our specialty will need to move to. By understanding the nature of the Porter's Five Forces as it applies to vascular surgery, and by appreciating their relative importance, our society would be in a stronger position to defend itself against threats and perhaps influence the forces with a long-term strategy. Porter's generic strategies attempt to create effective links for business with customers and suppliers and create barriers to new entrants and substitute products. It brings an initial perspective that is convenient to adapt to vascular surgery in order to reveal opportunities.Vascular surgery is uniquely situated to pursue both a differentiation and high value leadership strategy.

Comparison of orbital atherectomy plus balloon angioplasty vs. balloon angioplasty alone in patients with critical limb ischemia: results of the CALCIUM 360 randomized pilot trial

PURPOSE

To evaluate the role of orbital atherectomy in calcified infrapopliteal arteries in patients with critical limb ischemia compared to balloon angioplasty (BA) alone.

METHODS

A randomized multicenter study was undertaken to evaluate short and 1-year outcomes in 50 patients (32 men; mean age 71 years, range 40-90) with confirmed calcified lesions using 1∶1 randomization to the Diamondback 360° Orbital Atherectomy System followed by BA vs. BA alone. All patients had severe (≥50% stenosis) peripheral artery disease (Rutherford classification 4-6) in the popliteal, tibial, and/or peroneal arteries. The primary endpoint was defined as restoration of a normal lumen (residual stenosis ≤30%) with no bailout stenting or dissection types C through F. Scheduled follow-up visits were conducted according to a common protocol at 1, 6, and 12 months.

RESULTS

Procedural success was 93.1% (27/29 lesions) for atherectomy + BA patients and 82.4% (28/34 lesions) for BA alone (p = 0.27). Bailout stenting was needed in 2 (6.9%) of the 29 atherectomy + BA lesions and in 5 (14.3%) of the 35 BA-treated lesions (p = 0.44). At 1 year, there were no amputations in either group related to the index procedure. Estimates for freedom from target vessel revascularization and all-cause mortality were 93.3% and 100% in the atherectomy + BA group vs. 80.0% (p = 0.14) and 68.4% (p = 0.01) in the BA group, respectively. Proportional hazard models evaluating survival time vs. status of residual stenosis determined a hazard ratio for major adverse events of 5.6 for patients with an acute post-procedure residual stenosis >30% (p = 0.01).

CONCLUSION

Debulking with orbital atherectomy appeared to increase the chance of reaching a desirable angioplasty result, with less acute need for bailout stenting and a higher procedure success. A negative association between procedure success and risk of serious adverse outcomes should encourage larger confirmatory studies.

Photoplethysmography and continuous-wave Doppler ultrasound as a complementary test to ankle-brachial index in detection of stenotic peripheral arterial disease

PURPOSE

We evaluated the sensitivity and specificity of ankle-brachial index (ABI), photoplethysmography (PPG), and continuous-wave Doppler ultrasound (CWD) in the detection of anatomically stenotic peripheral arterial disease (PAD).

METHODS

Ninety-seven patients (194 legs) patients who had coincidentally undergone computed tomography angiography (CTA), ABI, PPG, and CWD for the evaluation of PAD were retrospectively reviewed. Sensitivity and specificity were measured.

RESULTS

Among 194 legs, 163 (84%) legs had stenotic PAD on CTA. Overall sensitivity of ABI, PPG, and CWD was 69.3%, 81.6%, and 90.8% and specificity was 96.8%, 77.4%, and 64.5%, respectively. Ankle-brachial index showed a statistically significantly decreased sensitivity (14.8%) for below trifurcation level stenosis compared with CWD (92%) and PPG (67%). The sensitivity of ABI was also significantly decreased in single level and moderate stenosis (45.1% and 42.1%, respectively). In contrast, the sensitivity of CWD and PPG was not significantly decreased.

CONCLUSION

The ABI showed significantly decreased sensitivity especially in stenosis below the trifurcation level. Both PPG and CWD were complementary to ABI in these groups of patients.

Procedural trends in the treatment of peripheral arterial disease by insurer status in New York State

BACKGROUND

Type or lack of insurance may affect access to care, treatment, and outcomes. We evaluated trends for surgical management of all peripheral arterial disease (PAD) in-hospital admissions by insurer status in New York State.

STUDY DESIGN

Statewide Planning and Research Cooperative System (SPARCS) data were obtained and cross-referenced for diagnostic and procedure codes. Data from 2001 to 2002 were averaged and used as a baseline. Change in indication, volume of admissions, procedures, and amputations were calculated for the years 2003 to 2008 and were analyzed by insurer status.

RESULTS

There were 83,949 admissions. Endovascular intervention (EVI) increased tremendously for all indications and was used equally in the insured and uninsured. Among critical limb ischemia admissions, patients with private insurance were significantly more likely to be admitted for rest pain and significantly less likely to be admitted for gangrene (p < 0.001). Admission for gangrene declined for all. As EVI increased, amputation decreased and was significantly lowest in patients with private insurance (p < 0.001). Amputation was significantly higher in Medicaid than other insured (Medicaid vs private, p < 0.001; Medicaid vs Medicare, p = 0.003), but comparable to the uninsured (p = 0.08). Age greater than 65 years and low socioeconomic class or minority status were significant risks for gangrene (p = 0.014; p < 0.001) and ultimate amputation (p = 0.05; p < 0.001). Lack of insurance may pose a similar risk.

CONCLUSIONS

EVI increased tremendously and was used without disparity across insurer status. Amputation declined steadily and may have been related to increased EVI or to decreased admission for gangrene. Advanced age, low socioeconomic class or minority status, and lack of insurance negatively affect presentation and limb salvage. Universal health care may be beneficial in improving outcomes but must address root causes for delayed presentation.

Psychometric properties of the disease-specific health-related quality of life instrument VascuQoL in a Swedish setting

Background

Traditional outcome measures in peripheral arterial disease (PAD) provide insufficient information regarding patient benefit. It has therefore been suggested to add patient-reported outcome measures. The main aim of this study was to validate the Swedish Vascular Quality of Life questionnaire (VascuQoL) version, a patient-reported PAD-specific health-related quality of life (HRQoL) instrument.

Methods

Two-hundred PAD patients were consecutively recruited from two university hospitals. Out of the 200 subjects, 129 had intermittent claudication and 71 had critical limb ischemia. Mean age was 70 ± 9 y and 57% of the participants were male. All patients completed SF-36 and VascuQoL at the vascular outpatient clinic, when evaluated for invasive treatment. Risk factors and physiological parameters were registered. Construct validity was tested by correlation analysis versus SF-36 and was also assessed with multitrait/multi-item scaling analysis (MTMI). Sensitivity analysis regarding disease severity identification was performed. Reliability was assessed with Cronbach's alpha and responsiveness by standardized response mean (SRM) calculations.

Results

Significant correlations were demonstrated between relevant subscales of VascuQoL and SF-36. MTMI showed acceptable construct validity, but some scaling-errors. VascuQoL significantly (p < 0.001) discriminated claudicants from critical limb ischemia patients. Cronbach's alpha was 0.94 and SRM 1.02 (sum score).

Conclusions

The Swedish version of VascuQoL is valid and quantifies central aspects of HRQoL in PAD patients. Sensitivity analysis showed high ability to differentiate between disease severity and SRM illustrated excellent responsiveness. The relative abundance of items however makes use in the everyday clinical setting somewhat difficult.

Sex-specific time trends in first admission to hospital for peripheral artery disease in Scotland 1991–2007

Background

This study examined trends for all first hospital admissions for peripheral artery disease (PAD) in Scotland from 1991 to 2007 using the Scottish Morbidity Record.

Methods

First admissions to hospital for PAD were defined as an admission to hospital (inpatient and day-case) with a principal diagnosis of PAD, with no previous admission to hospital (principal or secondary diagnosis) for PAD in the previous 10 years.

Results

From 1991 to 2007, 41 593 individuals were admitted to hospital in Scotland for the first time for PAD. Some 23 016 (55·3 per cent) were men (mean(s.d.) age 65·7(11·7) years) and 18 577 were women (aged 70·4(12·8) years). For both sexes the population rate of first admissions to hospital for PAD declined over the study interval: from 66·7 per 100 000 in 1991-1993 to 39·7 per 100 000 in 2006-2007 among men, and from 43·5 to 29·1 per 100 000 respectively among women. After adjustment, the decline was estimated to be 42 per cent in men and 27 per cent in women (rate ratio for 2007 versus 1991: 0·58 (95 per cent confidence interval 0·55 to 0·62) in men and 0·73 (0·68 to 0·78) in women). The intervention rate fell from 80·8 to 74·4 per cent in men and from 77·9 to 64·9 per cent in women. The proportion of hospital admissions as an emergency or transfer increased, from 23·9 to 40·7 per cent among men and from 30·0 to 49·5 per cent among women.

Conclusion

First hospital admission for PAD in Scotland declined steadily and substantially between 1991 and 2007, with an increase in the proportion that was unplanned.

Population-based analysis of inpatient vascular procedures and predicting future workload and implications for training

OBJECTIVE

The purpose of this study was to analyze the trend in inpatient vascular procedures in the United States over the past decade and predict the future demand for vascular surgeons.

METHODS

The Healthcare Cost and Utilization Project Nationwide Inpatient Sample was queried to determine the weighted national estimates of inpatient vascular procedures performed on adult patients (age ≥ 18) between 1997 and 2008. Using population estimates from the United States Census Bureau, the per capita rates of inpatient procedures were calculated for age-specific groups (18-64 years, 65-84 years, and ≥ 85 years). The change in per capita rates over the past decade along with population forecasts were used to predict future workload.

RESULTS

There was a net increase of 22% from 971,046 inpatient vascular procedures for all adults in 1997 to 1,188,332 in 2008. During the same time period, the adult population increased by 16% from 198 to 230 million. The age-stratified per capita rates of all vascular procedures were +21% for age 18 to 64; -4% for age 65 to 84; and +18% for age ≥ 85. This resulted in a net increase of 5% (490 to 515 procedures per 100,000 capita) in the per capita rate for all adults. Based on the assumption that trends in age-specific rates remain constant, there is a predicted inpatient workload increase (compared to 2008) of 18% by 2015, 34% by 2020, and 72% by 2030. The vascular workload is predicted to more than double by the year 2040.

CONCLUSIONS

Despite a conservative approach of using a population-based analysis of only inpatient procedures, there is a dramatic increase in the predicted vascular workload for the future. The vascular surgery training process will need to adapt to ensure an adequate number of fellowship-trained vascular surgeons is available to provide quality vascular care in the future.

Predicting functional status following amputation after lower extremity bypass

BACKGROUND

Some patients who undergo lower extremity bypass (LEB) for critical limb ischemia ultimately require amputation. The functional outcome achieved by these patients after amputation is not well known. Therefore, we sought to characterize the functional outcome of patients who undergo amputation after LEB, and to describe the pre- and perioperative factors associated with independent ambulation at home after lower extremity amputation.

METHODS

Within a cohort of 3,198 patients who underwent an LEB between January, 2003 and December, 2008, we studied 436 patients who subsequently received an above-knee (AK), below-knee (BK), or minor (forefoot or toe) ipsilateral or contralateral amputation. Our main outcome measure consisted of a "good functional outcome," defined as living at home and ambulating independently. We calculated univariate and multivariate associations among patient characteristics and our main outcome measure, as well as overall survival.

RESULTS

Of the 436 patients who underwent amputation within the first year following LEB, 224 of 436 (51.4%) had a minor amputation, 105 of 436 (24.1%) had a BK amputation, and 107 of 436 (24.5%) had an AK amputation. The majority of AK (75 of 107, 72.8%) and BK amputations (72 of 105, 70.6%) occurred in the setting of bypass graft thrombosis, whereas nearly all minor amputations (200 of 224, 89.7%) occurred with a patent bypass graft. By life-table analysis at 1 year, we found that the proportion of surviving patients with a good functional outcome varied by the presence and extent of amputation (proportion surviving with good functional outcome = 88% no amputation, 81% minor amputation, 55% BK amputation, and 45% AK amputation, p = 0.001). Among those analyzed at long-term follow-up, survival was slightly lower for those who had a minor amputation when compared with those who did not receive an amputation after LEB (81 vs. 88%, p = 0.02). Survival among major amputation patients did not significantly differ compared with no amputation (BK amputation 87%, p = 0.14, AK amputation 89%, p = 0.27); however, this part of the analysis was limited by its sample size (n = 212). In multivariable analysis, we found that the patients most likely to remain ambulatory and live independently despite undergoing a lower extremity amputation were those living at home preoperatively (hazard ratio [HR]: 6.8, 95% confidence interval [CI]: 0.94-49, p = 0.058) and those with preoperative statin use (HR: 1.6, 95% CI: 1.2-2.1, p = 0.003), whereas the presence of several comorbidities identified patients less likely to achieve a good functional outcome: coronary disease (HR: 0.6, 95% CI: 0.5-0.9, p = 0.003), dialysis (HR: 0.5, 95% CI: 0.3-0.9, p = 0.02), and congestive heart failure (HR: 0.5, 95% CI: 0.3-0.8, p = 0.005).

CONCLUSIONS

A postoperative amputation at any level impacts functional outcomes following LEB surgery, and the extent of amputation is directly related to the effect on functional outcome. It is possible, based on preoperative patient characteristics, to identify patients undergoing LEB who are most or least likely to achieve good functional outcomes even if a major amputation is ultimately required. These findings may assist in patient education and surgical decision making in patients who are poor candidates for lower extremity bypass.