Abdul Mueed Zafar

Lower-Extremity Endovascular Interventions for Medicare Beneficiaries: Comparative Effectiveness as a Function of Provider Specialty

PURPOSE Lower-extremity endovascular interventions are increasingly being performed by vascular surgeons (VSs) and interventional cardiologists (ICs) in addition to interventional radiologists (IRs). Regardless of specialty, well trained, experienced, and dedicated operators are expected to offer the best outcomes. To examine specialty-specific trends, outcomes of percutaneous lower-extremity revascularizations in Medicare beneficiaries were compared according to physician specialty types providing the service. MATERIALS AND METHODS Medicare Standard Analytical Files that contain longitudinal data of all services (physician, inpatient, outpatient) provided to a 5% sample of Medicare beneficiaries were studied. All claims for percutaneous angioplasty, atherectomy, and stent implantation of lower-extremity arteries during the years 2005–2007 were extracted, and the following outcomes were assessed: mortality, transfusion, intensive care unit (ICU) use, length of stay, and subsequent revascularization or amputation. Outcomes were compared by using regression models adjusted for age, sex, race, emergency department admission, and comorbid conditions. RESULTS Most outcomes were significantly worse if the service was provided by vascular surgeons compared with other vascular specialists. The in-hospital mortality rate for procedures performed by VSs was 19% higher than for those performed by others, but this difference was not significant (P =.351). Adjusted average 1-year procedure costs were significantly lower for IRs (

Prevalence of low ankle-brachial index, elevated plasma fibrinogen and CRP across Framingham risk categories: Data from the National Health and Nutrition Examination Survey (NHANES) 1999–2004

17,640) than for VSs (

Growth of carotid artery duplex ultrasound among Medicare beneficiaries (2000-2007).

19,012) or ICs (

Clinical Presentation, Imaging, and Management of Acute Cholecystitis

19,096). CONCLUSIONS Medicare data show that endovascular lower-extremity revascularization by vascular surgeons results in more transfusion and ICU use, longer hospital stay, more repeat revascularization procedures or amputations, and higher costs compared with procedures performed by interventional radiologists.

Benign pneumatosis intestinalis after bilateral lung transplantation.

OBJECTIVE 60-80% of heart attacks or coronary-related deaths occur in individuals identified as non-high-risk per the conventional risk assessment algorithms. Abnormal ankle-brachial index (ABI), plasma fibrinogen and plasma C-reactive protein (CRP) have been shown to be associated with a higher risk of cardiovascular disease (CVD). However, comparable data have not been reported for prevalence of abnormal ABI, fibrinogen and CRP in non-high-risk population. METHODS We analyzed data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES), a nationally representative cross-sectional survey of the U.S. population, for 6292 men and women, aged 40 and older, without known CVD or diabetes, with available data on standard CVD risk factors, ABI, fibrinogen and CRP. The main objective was to identify proportions of individuals with abnormal ABI (ABI<0.9 in either leg), elevated fibrinogen (≥ 400 mg/dl), and elevated CRP (>3mg/l), with otherwise low or intermediate (<20%) 10-year Framingham risk score. RESULTS Overall prevalence of abnormal ABI, fibrinogen, and CRP was 3.6% (95% CI 3.2-4.1%), 27.4% (95% CI 23.9-31.0%) and 38.3% (95% CI 36.5-40.0%) respectively. Among those with ABI data, 91.4% were at <20% FRS, and of these only 2.7% (95% CI 2.3-3.1%, p < 0.0001) had an abnormal ABI. Among those with fibrinogen data, 90.8% were at <20% FRS, and of these 23.6% (95% CI 20.4-26.8%, p < 0.001) had elevated plasma fibrinogen. Among those with CRP data, 91.1% were at <20% FRS, and of these 34.3% (95% CI 32.7-36.0%, p = 0.0012) had an elevated CRP. Overall, 45.0% (95% CI 42.2-47.8%; p < 0.0001) had abnormal ABI, fibrinogen or CRP but low-intermediate risk. CONCLUSION Abnormal ABI, elevate fibrinogen and CRP are highly prevalent among individuals otherwise at low-intermediate risk. If any or all of them are shown to improve predictive ability of FRS for primary prevention, it would have a significant public health impact.

Has the significance of incidental findings on unenhanced computed tomography for urolithiasis been overestimated? A retrospective review of over 800 patients.

OBJECTIVE Although intervention in asymptomatic carotid artery stenosis remains controversial, most carotid interventions are performed in asymptomatic individuals. Carotid duplex ultrasound is the diagnostic test that precedes more than 90% of carotid interventions. In terms of economic incentives, providers who perform carotid artery revascularization may experience synergy if they also provide carotid duplex ultrasound, because the diagnostic service is reimbursed and also can lead to referrals for revascularization procedures. To test the hypothesis that providers of revascularization services are incentivized to increase utilization of carotid duplex ultrasound, we compared the utilization of carotid duplex ultrasound among Medicare beneficiaries by three specialties that perform revascularization for carotid stenosis (interventional radiology, vascular surgery, and cardiology) with one that usually does not (diagnostic radiology). MATERIALS AND METHODS We analyzed 100% of procedure-specific claims submitted to Medicare by the four specialties during 2000, 2002, 2004, 2005, 2006, and 2007. Only professional and global components of services approved by Medicare were included. Compounded annual growth rates were used to compare utilization by different specialties. RESULTS Utilization by diagnostic radiology increased at a compound annual growth rate of 1% during 2000-2007. Interventional radiology and vascular surgery experienced higher compound annual growth rates of 3% and 6%, respectively. Utilization by cardiology increased at a rate 11 times that of diagnostic radiology, translating into an additional 960 procedures per 100,000 Medicare beneficiaries by cardiology in 2007 than in 2000. CONCLUSION Medicare beneficiaries are increasingly being tested for carotid artery stenosis, especially by specialties that perform revascularization for carotid stenosis. The health benefits of this practice are uncertain.

Understanding Preprocedure Patient Flow in IR

Acute cholecystitis (AC) is a life-threatening emergency that commonly occurs as a complication of gallstones. Severe right upper quadrant pain, abdominal guarding, fever, and a positive Murphys sign with an elevated white blood cell count are the classical clinical manifestations of AC. Although ultrasonography is typically the initial diagnostic examination in patients with suspected AC, computed tomography and magnetic resonance imaging are commonly performed to identify complications; cholescintigraphy is recommended in patients with equivocal findings on the other imaging modalities, as this technique has the highest diagnostic accuracy in the diagnosis of AC. Imaging studies are also helpful in the timely detection of complications associated with AC. Although laparoscopic cholecystectomy is considered the gold-standard treatment for AC, percutaneous gallbladder drainage with or without cholecystostomy tube placement is a safe, effective management technique for surgically high-risk patients with multiple medical conditions. This treatment can be used as either a bridging therapy, with elective cholecystectomy performed at a later time after improvement of the patients condition, or as definitive treatment in surgically unfit patients. Radiologists play a pivotal role in the initial diagnosis and management of patients with AC.

It’s the Man Not the Machine

This series details two cases of benign pneumatosis intestinalis (PI) in patients post-lung transplant, which were discovered incidentally on routine surveillance chest radiographs during ambulatory clinic visits. Both patients had uneventful post-transplant recovery and were asymptomatic at presentation. The patients were admitted for observation. Contrast-enhanced abdominal CT scans confirmed the plain film findings. Both cases were managed conservatively with bowel rest, intravenous hydration and serial abdominal examinations. The patients had unremarkable hospital courses and were both discharged in good condition. Our current understanding of benign PI in patients post-transplant is limited to a few case series and case reports. Greater awareness of this entity may decrease unnecessary invasive procedures and improve management of these patients.

Performance of current guidelines for coronary heart disease prevention: Optimal use of the Framingham-based risk assessment

Abstract Objectives: To evaluate the detection of clinically unsuspected pathologies using 64-slice multidetector computed tomography (CT) of the abdomen in patients with flank pain. The presence of significant incidental findings (those warranting immediate management) was also correlated with that of urolithiasis, to assess potential changes of management. Patients and methods: The study included 899 patients undergoing CT in a 6-month period between June and December 2008. Patients who were referred from outside, with no medical record in the hospital where the study was conducted, and those who were lost to follow-up, were excluded. All of the CT examinations were reported after a radiology resident and a consultant radiologist with >4 years of experience evaluated the CT. Genitourinary and extra-genitourinary findings were assessed and divided into clinically significant or not. Results: The overall incidence of additional and incidental findings was 14%. Besides urolithiasis and obstruction there were 34 (28%) genitourinary findings and 87 (72%) extra-genitourinary findings; most of the former were insignificant. Of the extra-genitourinary findings, significant diagnoses were documented in 34 cases. Conclusions: Abdominal multidetector CT detects more incidental findings which are clinically significant.

Utilization of lower extremity arterial disease diagnostic and revascularization procedures in Medicare beneficiaries 2000-2007.

PURPOSE To quantify preprocedural patient flow in interventional radiology (IR) and to identify potential contributors to preprocedural delays. MATERIALS AND METHODS An administrative dataset was used to compute time intervals required for various preprocedural patient-flow processes. These time intervals were compared across on-time/delayed cases and inpatient/outpatient cases by Mann-Whitney U test. Spearman ρ was used to assess any correlation of the rank of a procedure on a given day and the procedure duration to the preprocedure time. A linear-regression model of preprocedure time was used to further explore potential contributing factors. Any identified reason(s) for delay were collated. P < .05 was considered statistically significant. RESULTS Of the total 1,091 cases, 65.8% (n = 718) were delayed. Significantly more outpatient cases started late compared with inpatient cases (81.4% vs 45.0%; P < .001, χ(2) test). The multivariate linear regression model showed outpatient status, length of delay in arrival, and longer procedure times to be significantly associated with longer preprocedure times. Late arrival of patients (65.9%), unavailability of physicians (18.4%), and unavailability of procedure room (13.0%) were the three most frequently identified reasons for delay. The delay was multifactorial in 29.6% of cases (n = 213). CONCLUSIONS Objective measurement of preprocedural IR patient flow demonstrated considerable waste and highlighted high-yield areas of possible improvement. A data-driven approach may aid efficient delivery of IR care.