Gaurav Parmar

Protocol Implementation of Selective PostOperative Lumbar Spinal Drainage after Thoracic Aortic Endograft

BACKGROUND Spinal cord ischemia (SCI) remains a significant concern in patients undergoing endovascular repair involving the thoracic aorta (thoracic endovascular aortic repair [TEVAR]). Perioperative lumbar spinal drainage has been widely practiced for open repair, but there is no consensus treatment protocol using lumbar drainage for SCI associated with TEVAR. This study analyzes the efficacy of an institutional protocol using selective lumbar drainage reserved for patients experiencing SCI following TEVAR. METHODS A prospectively maintained registry was reviewed to identify all patients who underwent TEVAR from January 2000 through June 2010. Preoperative characteristics, intraoperative details, and outcomes, including neurologic deficit and mortality at 30 days and 1 year were determined based on reporting standards. Patients developing symptoms of SCI in the postoperative setting were compared with those without neurologic symptoms. SCI patients who received selective lumbar drainage were grouped based on resolution of neurologic function, with risk factors and outcomes of these subgroups analyzed with χ(2), t test, logistic regression, and analysis of variance (ANOVA). RESULTS Two hundred seventy-eight TEVARs were performed on 251 patients. Twelve patients accounting for 12 TEVARs were excluded from analysis: 5 patients experienced SCI preoperatively, 4 patients were drained preoperatively, 2 expired intraoperatively, and 1 procedure was aborted. Of the remaining 266 procedures in 239 patients, 16 (6.0%) developed SCI within the 30-day postoperative period. Risk factors for SCI reaching statistical significance included length of aortic coverage (P = .036), existence of infrarenal aortic pathology (P = .026), and history of stroke (P = .043). Stent graft coverage of the left subclavian artery origin was required in 28.9% (n = 77) and was not associated with SCI (P = .52). Ten of 16 post-TEVAR SCI patients received selective postoperative lumbar drains and were categorized based on resolution of symptoms into complete resolution (n = 3; 30%), partial resolution (n = 4; 40%), and no resolution (n = 3; 30%). No patient characteristics or risk factors reached significance in comparison of lumbar drained patients and nondrained patients. All seven drained patients without complete resolution of SCI died within the first year after surgery, while all three of the complete responders survived (P = .017). In patients with SCI, increased all-cause mortality was observed at 1 year (56.3% vs 20.4%; P = .003). CONCLUSIONS A protocol utilizing selective postoperative lumbar spinal drainage can be used safely for patients developing SCI after TEVAR with acceptably low permanent neurologic deficit, although overall survival of patients experiencing SCI after TEVAR is diminished relative to non-SCI patients.

Long-term single institution comparison of endovascular aneurysm repair and open aortic aneurysm repair

INTRODUCTION Since the development of endovascular aneurysm repair (EVAR), there remains concerns regarding its durability, need for secondary procedures, and associated long-term morbidity. We compared these two approaches to evaluate secondary interventions and their respective long-term durability. METHODS All patients who had undergone endovascular and open abdominal aortic aneurysm (AAA) repair were identified from a prospectively maintained registry. Health system charts, medical communication, and national death indexes were reviewed. Secondary interventions were classified as vascular (aortic graft or remote) and nonvascular (incisional or gastrointestinal). RESULTS Between July 1985 and September 2009, 1908 patients underwent 1986 AAA repair procedures (EVAR = 1066; open = 920). Patients were followed up to 290 months (mean 27.6 ± 35.9) and identified with 427 surgical encounters (EVAR 233% to 21.9%; open 194% to 21.1%). Most encounters (338% to 74.6%) were related to vascular disease: 178 (EVAR = 131; open = 47) related to the aortic graft; 160 (EVAR = 93; open = 67) were related to nonaortic vascular disease. The remaining 89 surgical encounters included incisional hernias, small bowel obstruction, intra-abdominal abscesses, and wound dehiscence requiring operation. Of these 89 encounters (EVAR = 9; open = 80), 44 patients required surgical intervention and 36 required hospitalization without surgical procedure. Over the period of 100 months, the all-cause mortality rate was 25.2% after EVAR and 39.1% after open repair. One-year survival was 88.0% (SE 0.01) and 85.0% (SE 0.01), while 5-year survival was 58.0% (SE 0.02) and 53.0% (SE 0.02) for EVAR and open repair, respectively (log-rank P value < .0164). Seven-year survival was 46% (SE 0.03) for EVAR and 36% (SE 0.03) for open AAA repair. CONCLUSION EVAR requires more late secondary vascular interventions than open AAA repair, but patients who undergo open repair have more nonvascular long-term morbidity. Long-term survival is better after EVAR compared to open repair in this selected patient group.

Hospital laboratory reporting may be a barrier to detection of ‘microsize’ myocardial infarction in the US: an observational study

BackgroundInternational guidelines recommend that the decision threshold for troponin should be the 99th percentile of a normal population, or, if the laboratory assay is not sufficiently precise at this low level, the level at which the assay achieves a 10% or better coefficient of variation (CV). Our objectives were to examine US hospital laboratory troponin reports to determine whether either the 99th percentile or the 10% CV level were clearly indicated, and whether nonconcordance with these guidelines was a potential barrier to detecting clinically important microscopic or ‘microsize’ myocardial infarctions (MIs). To confirm past reports of the clinical importance of microsize MIs, we also contrasted in-hospital, 28-day and 1-year mortality among those with microsize and nonmicrosize MI.MethodsIn the REasons for Geographic And Racial Differences in Stroke national prospective cohort study (n=30,239), 1029 participants were hospitalized for acute coronary syndrome (ACS) between 2003–2009. For each case, we recorded all thresholds of abnormal troponin on the laboratory report and whether the 99th percentile or 10% CV value were clearly identified. All cases were expert adjudicated for presence of MI. Peak troponin values were used to classify MIs as microsize MI (< five times the lowest listed upper limit of normal) and nonmicrosize MI.ResultsParticipants were hospitalized at 649 acute care US hospitals, only 2% of whose lab reports clearly identified the 99th percentile or the 10% CV level; 52% of reports indicated an indeterminate range, a practice that is no longer recommended. There were 183 microsize MIs and 353 nonmicrosize MIs. In-hospital mortality tended to be lower in the microsize than in the nonmicrosize MI group (1.1 vs. 3.6%, p = 0.09), but 28-day and 1-year mortality were similar (2.5% vs. 2.7% [p = 0.93] and 5.2% vs. 4.3% [p = 0.64], respectively).ConclusionsCurrent practices in many US hospitals created barriers to the clinical recognition of microsize MI, which was common and clinically important in our study. Improved hospital troponin reporting is warranted.

Health Professional Shortage Areas, Insurance Status, and Cardiovascular Disease Prevention in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Individuals with cardiovascular disease (CVD) living in Health Professional Shortage Areas (HPSA) may receive less preventive care than others. The Reasons for Geographic And Racial Differences in Stroke Study (REGARDS) surveyed 30,239 African American (AA) and White individuals older than 45 years of age between 2003-2007. We compared medication use for CVD prevention by HPSA and insurance status, adjusting for sociodemographic factors, health behaviors, and health status. Individuals residing in partial HPSA counties were excluded. Mean age was 64±9 years, 42% were AA, 55% were women, and 93% had health insurance; 2,545 resided in 340 complete HPSA counties and 17,427 in 1,145 non-HPSA counties. Aspirin, beta-blocker, and ACE-inhibitor use were similar by HPSA and insurance status. Compared with insured individuals living in non-HPSA counties, statin use was lower among uninsured participants living in non-HPSA and HPSA counties. Less medication use for CVD prevention was not associated with HPSA status, but less statin use was associated with lack of insurance.

Effect of lipid-modifying drug therapy on survival after abdominal aortic aneurysm repair.

BACKGROUND Lipid-modifying drug therapy (LMDT) is recommended in all patients having coronary or noncoronary atherosclerotic disease. However, the effect of LMDT after abdominal aortic aneurysm (AAA) repair, especially in the absence of other atherosclerotic manifestations, is unclear. We examined the distribution of prevalence of LMDT among patients undergoing AAA repair and its effect on survival in the presence and absence of other atherosclerotic diseases. METHODS We identified patients treated at University of Alabama at Birmingham between 1985 and 2010 who had a prior AAA repair. Information was collected from health system medical charts, medical communication, and national death indices. We assessed the predictors of prevalence of LMDT by univariate analysis using t-test for continuous and χ(2) test for categorical variables, and then performed multivariate logistic regression. The survival was determined using Kaplan-Meier plots, and adjusted hazard ratios were calculated using Cox proportion regression. RESULTS A total of 2063 patients underwent AAA repair procedure. Of these, 9% were African-American, and 20% were female. Thirty-five percent received LMDT, and 32% died during the follow-up period of up to 240 months. Significant predictors for being on LMDT included white race (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.2), presence of other atherosclerotic disease or diabetes (OR, 2.4; 95% CI, 1.9-3.0), hypertension (OR, 4.0; 95% CI, 3.1-5.2), smoking (OR, 1.6; 95% CI, 1.2-2.1), and endovascular AAA repair (OR, 1.9; 95% CI, 1.5-2.3). LMDT was associated with improved survival (hazard ratio, 0.6; 95% CI, 0.5-0.8) after controlling for traditional risk factors, diabetes, and other atherosclerotic diseases. CONCLUSIONS LMDT after AAA is associated with an increased survival compared with patients who were not using drug therapy for dyslipidemia. Aggressive management of dyslipidemia should be considered in all patients undergoing AAA repair irrespective of other atherosclerotic disease status and risk factor profile.

Awareness, Treatment and Control of Hypertension, Diabetes and Hyperlipidemia and Area-Level Mortality Regions in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Background. Health Professional Shortage Areas (HPSA) receive extra federal resources, but recent reports suggest that HPSA may not consistently identify areas of need. Purpose. To assess areas of need based on county-level ischemic heart disease (IHD) and stroke mortality regions. Methods. Need was defined by lack of awareness, treatment, or control of hypertension, diabetes, or hyperlipidemia. Counties were categorized into race-specific tertiles of IHD and stroke mortality using 1999-2006 CDC data. Multivariable logistic regression was used to model the relationships between IHD and stroke mortality region and each element of need. Results. Awareness and treatment of cardiovascular (CVD) risk factors were similar for residents in counties across IHD and stroke mortality tertiles, but control tended to be lower in counties with the highest mortality. Conclusions. High stroke and IHD mortality identify distinct regions from current HPSA designations, and may be an additional criterion for designating areas of need.

Awareness and management of chronic disease, insurance status, and health professional shortage areas in the REasons for Geographic And Racial Differences in Stroke (REGARDS): a cross-sectional study.

BackgroundLimited financial and geographic access to primary care can adversely influence chronic disease outcomes. We examined variation in awareness, treatment, and control of hypertension, diabetes, and hyperlipidemia according to both geographic and financial access to care.MethodsWe analyzed data on 17,458 participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study with either hypertension, hyperlipidemia, or diabetes and living in either complete Health Professional Shortage Area (HPSA) counties or non-HPSA counties in the U.S. All analyses were stratified by insurance status and adjusted for sociodemographics and health behaviors.Results2,261 residents lived in HPSA counties and 15,197 in non-HPSA counties. Among the uninsured, HPSA residents had higher awareness of both hypertension (adjusted OR 2.30, 95% CI 1.08, 4.89) and hyperlipidemia (adjusted OR 1.50, 95% CI 1.01, 2.22) compared to non-HPSA residents. Also among the uninsured, HPSA residents with hypertension had lower blood pressure control (adjusted OR 0.45, 95% CI 0.29, 0.71) compared with non-HPSA residents. Similar differences in awareness and control according to HPSA residence were absent among the insured.ConclusionsDespite similar or higher awareness of some chronic diseases, uninsured HPSA residents may achieve control of hypertension at lower rates compared to uninsured non-HPSA residents. Federal allocations in HPSAs should target improved quality of care as well as increasing the number of available physicians.

Cardiovascular outcome ascertainment was similar using blinded and unblinded adjudicators in a national prospective study

OBJECTIVE Observational studies can avoid biases by blinding medical records to characteristics of interest before outcome adjudication. However, blinding is costly. We assessed the effect of blinding race and geography on outcome ascertainment. STUDY DESIGN AND SETTING The Reasons for Geographic and Racial Differences in Stroke - Myocardial Infarction (REGARDS-MI) Study is an ancillary study to the REGARDS national prospective cohort study including 30,228 participants. The primary characteristics of interest are race and geography, and the prespecified acceptable agreement rate between adjudicators is set at less than 80%. We selected 116 suspected cardiovascular events that underwent adjudication with usual blinding. At least 3 months later, cases were readjudicated without blinding race and geographic location of the patient. We assessed differences in outcome ascertainment using Cohens kappa statistic and ARs. RESULTS Agreement between blinded and unblinded reviews was good to excellent for all four outcomes. kappa statistics were 0.80 (chest pain), 0.85 (heart failure), 0.86 (revascularization), and 0.74 (MI) (P<0.0001 for all). Within each outcome, ARs were similar for race and geographic groups (agreement: 83-100%). CONCLUSION In observational studies, blinding medical record review for outcome ascertainment for some types of patient characteristics may cause an unwarranted expense.