Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Christina M. Vassileva is active.

Publication


Featured researches published by Christina M. Vassileva.


Journal of the American College of Cardiology | 2017

2017 ACC Expert Consensus Decision Pathway for Transcatheter Aortic Valve Replacement in the Management of Adults With Aortic Stenosis: A Report of the American College of Cardiology Task Force on Clinical Expert Consensus Documents

Catherine M. Otto; Dharam J. Kumbhani; Karen P. Alexander; John H. Calhoon; Milind Y. Desai; Sanjay Kaul; James C. Lee; Carlos E. Ruiz; Christina M. Vassileva

James L. Januzzi, Jr, MD, FACC, Chair Luis C. Afonso, MBBS, FACC Brendan M. Everett, MD, FACC Jonathan Halperin, MD, FACC Adrian Hernandez, MD, FACC William Hucker, MD, PhD Hani Jneid, MD, FACC Dharam J. Kumbhani, MD, SM, FACC Eva M. Lonn, MD, FACC Joseph Marine, MD, FACC James K. Min, MD


The Journal of Thoracic and Cardiovascular Surgery | 2012

Tricuspid valve surgery: The past 10 years from the Nationwide Inpatient Sample (NIS) database

Christina M. Vassileva; John Shabosky; Theresa M. Boley; Stephen Markwell; Stephen R. Hazelrigg

OBJECTIVES The purpose of this study was to examine the trends in tricuspid valve surgery over time. METHODS We used 10 years (1999-2008) of NIS data to examine the population of patients undergoing tricuspid valve repair or replacement (ICD-9-CM codes 35.14, 35.27, and 35.28). RESULTS We identified 28,726 admissions for tricuspid valve surgery. The total number of tricuspid procedures more than doubled over the 10- year period (1712 cases in 1999 vs 4072 cases in 2008). Although the absolute number of repairs and replacements increased over time, the tricuspid repair rate increased whereas there was a corresponding decrease in tricuspid replacement rate. Isolated tricuspid valve surgery accounted for 20% of the total tricuspid cases, whereas tricuspid surgery as a concomitant procedure to other cardiac operations accounted for the remaining 80%. There was a trend toward increased use of tissue over mechanical valves for tricuspid replacement. Overall hospital mortality was 10.6%. Over time, mortality decreased significantly for both repair and replacement. Concomitant tricuspid replacement was associated with significantly higher hospital mortality than was isolated tricuspid replacement (16.1% vs 10.1%; P = .0001). CONCLUSIONS There has been a dramatic increase in tricuspid interventions over time. This has been associated with an increase in tricuspid repair rates as well as use of bioprostheses for tricuspid replacement. The majority of tricuspid operations are performed concomitantly to other cardiac procedures. Mortality for tricuspid valve surgery remains considerable and significantly higher for replacement than for repair.


Circulation | 2013

Long Term Survival of Patients Undergoing Mitral Valve Repair and Replacement: A Longitudinal Analysis of Medicare Fee-for-Service Beneficiaries

Christina M. Vassileva; Gregory Mishkel; Christian McNeely; Theresa M. Boley; Stephen Markwell; Steven L. Scaife; Stephen R. Hazelrigg

Background— Despite the established superiority of mitral repair over replacement, its adoption in the treatment of elderly patients has not been uniform, partly because of a lack of robust long-term survival data. We present the long-term survival of Medicare fee-for-service beneficiaries undergoing mitral valve repair and replacement over a 10-year period. Methods and Results— We used the Medicare database to identify 47 279 fee-for-service beneficiaries ≥65 years of age undergoing primary isolated mitral valve repair or replacement from 2000 to 2009. Operative mortality and long-term survival are presented for repair and replacement. Operative mortality was 3.9% for patients undergoing repair and 8.9% for patients undergoing replacement. The 1-, 5-, and 10-year Kaplan-Meier survival estimates for patients undergoing repair were 90.9%, 77.1%, and 53.6%. The 1-, 5-, and 10-year Kaplan-Meier survival estimates for patients undergoing replacement were 82.6%, 64.7%, and 37.2%. Important predictors of mitral repair included younger age (odds ratio, 1.10; 95% confidence interval, 1.05–1.14), elective admission status (odds ratio, 1.34; 95% confidence interval, 1.27–1.41), and annual mitral procedure volume >40 cases per year (odds ratio, 1.57; 95% confidence interval, 1.36–1.81). Female sex and the presence of comorbidities were associated with a lower likelihood of repair. Conclusions— Mitral valve surgery in the Medicare population carries less risk than previously reported. Given the favorable outcomes of elderly patients undergoing mitral valve surgery, especially mitral valve repair, an approach of earlier identification and surgical referral appears justified regardless of age.Background— Despite the established superiority of mitral repair over replacement, its adoption in the treatment of elderly patients has not been uniform, partly because of a lack of robust long-term survival data. We present the long-term survival of Medicare fee-for-service beneficiaries undergoing mitral valve repair and replacement over a 10-year period. Methods and Results— We used the Medicare database to identify 47 279 fee-for-service beneficiaries ≥65 years of age undergoing primary isolated mitral valve repair or replacement from 2000 to 2009. Operative mortality and long-term survival are presented for repair and replacement. Operative mortality was 3.9% for patients undergoing repair and 8.9% for patients undergoing replacement. The 1-, 5-, and 10-year Kaplan-Meier survival estimates for patients undergoing repair were 90.9%, 77.1%, and 53.6%. The 1-, 5-, and 10-year Kaplan-Meier survival estimates for patients undergoing replacement were 82.6%, 64.7%, and 37.2%. Important predictors of mitral repair included younger age (odds ratio, 1.10; 95% confidence interval, 1.05–1.14), elective admission status (odds ratio, 1.34; 95% confidence interval, 1.27–1.41), and annual mitral procedure volume >40 cases per year (odds ratio, 1.57; 95% confidence interval, 1.36–1.81). Female sex and the presence of comorbidities were associated with a lower likelihood of repair. Conclusions— Mitral valve surgery in the Medicare population carries less risk than previously reported. Given the favorable outcomes of elderly patients undergoing mitral valve surgery, especially mitral valve repair, an approach of earlier identification and surgical referral appears justified regardless of age. # Clinical Perspective {#article-title-17}


The Journal of Thoracic and Cardiovascular Surgery | 2015

Hospital volume, mitral repair rates, and mortality in mitral valve surgery in the elderly: An analysis of US hospitals treating Medicare fee-for-service patients

Christina M. Vassileva; Christian McNeely; John A. Spertus; Stephen Markwell; Stephen R. Hazelrigg

BACKGROUND The volume-outcome relationship has been suggested as a quality metric in mitral valve surgery and would be particularly relevant in the elderly because of their greater burden of comorbidities and higher perioperative risk. METHODS AND RESULTS The study included 1239 hospitals performing mitral valve surgery on Medicare beneficiaries from 2000 through 2009. Only 9% of hospitals performed more than 40 mitral operations per year, 29% performed 5 or less, and 51% performed 10 or less. Mitral repair rates were low; 22.7% of hospitals performed 1 or less, 65.1% performed 5 or less, and only 5.6% performed more than 20 mitral repairs per year in those aged 65 years or more. Repair rates increased with increasing volume of mitral operations per year: 5 or less, 30.5%; 6 to 10, 32.9%; 11 to 20, 34.9%; 21 to 40, 38.8%; and more than 40, 42.0% (P = .0001). Hospitals with lower volume had significantly higher adjusted operative mortality compared with hospitals performing more than 40 cases per year: 5 or less cases per year, odds ratio (OR) 1.58 (95% confidence interval [CI], 1.40-1.78); 6 to 10 cases per year, OR 1.29 (95% CI, 1.17-1.43); 11 to 20 cases per year, OR 1.17 (95% CI, 1.07-1.28); 21 to 40 cases per year, OR 1.15 (95% CI, 1.05-1.26). Hospitals with lower mitral repair rates had an increased likelihood of operative mortality relative to the top quartile: lowest quartile, OR 1.31 (95% CI, 1.20-1.44); second quartile, OR 1.18 (95% CI, 1.09-1.29); and third quartile, OR 1.14 (95% CI, 1.05-1.24). Long-term mortality beyond 6 months was also higher in low-volume hospitals: 5 or less cases year, hazard ratio (HR) 1.11 (95% CI, 1.06-1.18); 6 to 10 cases per year, OR 1.06 (95% CI, 1.02-1.10) compared with hospitals performing more than 40 cases per year. CONCLUSIONS Most hospitals perform few mitral valve operations on elderly patients. Greater volume of mitral procedures was associated with higher repair rates. Both greater volume of mitral procedures and increasing mitral repair rates were associated with decreased mortality.


The Annals of Thoracic Surgery | 2015

Outcomes of Patients With Severe Chronic Lung Disease Who Are Undergoing Transcatheter Aortic Valve Replacement

Rakesh M. Suri; Brian C. Gulack; J. Matthew Brennan; Vinod H. Thourani; Dadi Dai; Alan Zajarias; Kevin L. Greason; Christina M. Vassileva; Verghese Mathew; Vuyisile T. Nkomo; Michael J. Mack; Charanjit S. Rihal; Lars G. Svensson; Rick A. Nishimura; Patrick T. O’Gara; David R. Holmes

BACKGROUND In this study, we sought to determine the clinical outcomes after transcatheter aortic valve replacement (TAVR) among patients with chronic lung disease (CLD) and to evaluate the safety of transaortic versus transapical alternate access approaches in patients with varying severities of CLD. METHODS Clinical records for patients undergoing TAVR from 2011 to 2014 in The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry were linked to Medicare hospital claims (n = 11,656). Clinical outcomes were evaluated across strata of CLD severity, and the risk-adjusted association between access route and post-TAVR mortality was determined among patients with severe CLD. RESULTS In this cohort (median age, 84 years; 51.7% female), moderate to severe CLD was present in 27.7% (14.3%, moderate; 13.4%, severe). Compared with patients with no or mild CLD, patients with severe CLD had a higher rate of post-TAVR mortality to 1-year (32.3% versus 21.0%; adjusted hazard ratio [HR], 1.48; 95% confidence interval [CI], 1.31 to 1.66), as did those with moderate CLD (25.5%; adjusted HR, 1.16; 95% CI, 1.03 to 1.30). The adjusted rate of mortality was similar for transapical versus transaortic approaches to 1 year (adjusted HR, 1.17; 95% CI, 0.83 to 1.65). CONCLUSIONS Moderate or severe CLD is associated with an increased risk of death to 1-year after TAVR, and among patients with severe CLD, the risk of death appears to be similar with either transapical or transaortic alternate-access approaches. Further study is necessary to understand strategies to mitigate risk associated with CLD and the long-term implications of these findings.


Heart Surgery Forum | 2011

Sex differences in procedure selection and outcomes of patients undergoing mitral valve surgery.

Christina M. Vassileva; Lacey M. Stelle; Steve Markwell; Theresa M. Boley; Stephen R. Hazelrigg

BACKGROUND There is a paucity of data on sex differences in procedure selection and outcomes of patients undergoing mitral valve surgery. METHODS AND RESULTS The National Inpatient Sample database from 2005 to 2008 was searched to identify patients ≥30 years of age who underwent mitral valve repair or replacement (ICD-9-CM codes 35.12, 35.23, and 35.24). Women constituted 51.6% of the patients, and they were older, were less affluent, had higher values for the Charlson comorbidity index, and more often presented on an urgent/emergent basis. Women underwent repair less often than men (37.9% versus 55.9%, P < .001) and more often underwent concomitant tricuspid surgery or a Maze procedure. After adjustment for propensity scores, women were more likely to undergo replacement (odds ratio, 1.78; 95% confidence interval, 1.64-1.93; P = .0001), they had longer lengths of stay, and less favorable disposition. Among the patients who underwent mitral valve repair, women had a higher hospital mortality (2.06% versus 1.36%, P = .0328). After adjustment for propensity scores and concomitant procedures, this relationship was no longer statistically significant. CONCLUSIONS Women are less likely than men to receive mitral valve repair. Although the higher hospital mortality of women presenting for mitral valve surgery was accounted for by their worse preoperative profiles, this sex disparity reflects the current reality in surgical practice and identifies an important area for future improvement in the care of patients with valvular heart disease.


The Annals of Thoracic Surgery | 2016

Trends in Patient Characteristics and Outcomes of Coronary Artery Bypass Grafting in the 2000 to 2012 Medicare Population

Christian McNeely; Stephen Markwell; Christina M. Vassileva

BACKGROUND The purpose of this analysis was to examine the trends in patient characteristics and outcomes in patients who underwent coronary artery bypass grafting (CABG) over a 12-year period in the Medicare database. METHODS The study included 1,264,265 isolated CABG procedures in the Medicare population from January 2000 through November 2012. Comorbidities were determined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnostic codes. Trends in patient characteristics and hospital outcomes were assessed with Cochran-Armitage trend tests. Long-term survival was examined with Kaplan-Meier survival curves. RESULTS The median age was 74 years. Comorbidity profiles increased significantly over time. The number of patients undergoing CABG decreased from 131,385 in 2000 to 71,086 in 2012. The majority of patients underwent multivessel revascularization (13.5% single-vessel CABG, 35.2% 2-vessel CABG, 32.1% 3-vessel CABG, and 15.7% ≥4-vessel CABG). The percentage of patients undergoing 1- and 2-vessel revascularization increased over time, whereas that of ≥3-vessel CABG decreased. Single internal mammary artery (IMA) use increased from 75.6% to 88.6%. Median length of stay (LOS) was 8 days. Thirty-day mortality decreased from 4.2% to 3.0%. Hospital mortality fell from 4.0% in 2000 to 2.7% in 2012 (odds ratio [OR], 0.73; 95% confidence interval [CI], 0.69-0.77). Survival was 93% at 6 months, 91% at 1 year, 84% at 3 years, and 76% at 5 years. Five-year survival changed little over time (range, 75%-77%). CONCLUSIONS Despite rising comorbidities in Medicare patients undergoing CABG, hospital mortality fell significantly from 2000 to 2012. When adjusted for comorbidities, this signified a 27% reduction in hospital mortality. IMA use increased during the study period, and there was a trend of decreased use of 3 or more grafts.


Current Cardiology Reviews | 2014

Long-term Outcomes of Mitral Valve Repair Versus Replacement for Degenerative Disease: A Systematic Review

Christian McNeely; Christina M. Vassileva

The short-term advantage of mitral valve repair versus replacement for degenerative disease has been extensively documented. These advantages include lower operative mortality, improved survival, better preservation of left-ventricular function, shorter post-operative hospital stay, lower total costs, and fewer valve-related complications, including thromboembolism, anticoagulation-related bleeding events and late prosthetic dysfunction. More recent written data are available indicating the long-term advantage of repair versus replacement. While at some institutions, the repair rate for degenerative disease may exceed 90%, the national average in 2007 was only 69%. Making direct comparisons between mitral valve repair and replacement using the available studies does present some challenges however, as there are often differences in baseline characteristics between patient groups as well as other dissimilarities between studies. The purpose of this review is to systematically summarize the long-term survival and reoperation data of mitral valve repair versus replacement for degenerative disease. A PubMed search was done and resulted in 12 studies that met our study criteria for comparing mitral valve repair versus replacement for degenerative disease. A systematic review was then conducted abstracting survival and reoperation data.


The Annals of Thoracic Surgery | 2016

Failure to Rescue Rates After Coronary Artery Bypass Grafting: An Analysis From The Society of Thoracic Surgeons Adult Cardiac Surgery Database

Fred H. Edwards; Victor A. Ferraris; Paul Kurlansky; Kevin W. Lobdell; Xia He; Sean M. O’Brien; Anthony P. Furnary; J. Scott Rankin; Christina M. Vassileva; Frank L. Fazzalari; Mitchell J. Magee; Vinay Badhwar; Ying Xian; Jeffrey P. Jacobs; Moritz C. Wyler von Ballmoos; David M. Shahian

BACKGROUND Failure to rescue (FTR) is increasingly recognized as an important quality indicator in surgery. The Society of Thoracic Surgeons National Database was used to develop FTR metrics and a predictive FTR model for coronary artery bypass grafting (CABG). METHODS The study included 604,154 patients undergoing isolated CABG at 1,105 centers from January 2010 to January 2014. FTR was defined as death after four complications: stroke, renal failure, reoperation, and prolonged ventilation. FTR was determined for each complication and a composite of the four complications. A statistical model to predict FTR was developed. RESULTS FTR rates were 22.3% for renal failure, 16.4% for stroke, 12.4% for reoperation, 12.1% for prolonged ventilation, and 10.5% for the composite. Mortality increased with multiple complications and with specific combinations of complications. The multivariate risk model for prediction of FTR demonstrated a C index of 0.792 and was well calibrated, with a 1.0% average difference between observed/expected (O/E) FTR rates. With centers grouped into mortality terciles, complication rates increased modestly (11.4% to 15.7%), but FTR rates more than doubled (6.8% to 13.9%) from the lowest to highest terciles. Centers in the lowest complication rate tercile had an FTR O/E of 1.14, whereas centers in the highest complication rate tercile had an FTR O/E of 0.91. CONCLUSIONS CABG mortality rates vary directly with FTR, but complication rates have little relation to death. FTR rates derived from The Society of Thoracic Surgeons data can serve as national benchmarks. Predicted FTR rates may facilitate patient counseling, and FTR O/E ratios have promise as valuable quality metrics.


American Heart Journal | 2016

Readmission after inpatient percutaneous coronary intervention in the Medicare population from 2000 to 2012

Christian McNeely; Stephen Markwell; Christina M. Vassileva

BACKGROUND Since year 2000, reducing hospital readmissions has become a public health priority. In addition, there have been major changes in percutaneous coronary intervention (PCI) during this period. METHODS The cohort consisted of 3,250,194 patients admitted for PCI from January 2000 through November 2012. RESULTS Overall, 30-day readmission was 15.8%. Readmission rates declined from 16.1% in 2000 to 15.4% in 2012 (adjusted odds ratio for readmission 1.33 in 2000 compared with 2012). Of all readmissions after PCI, the majority were for cardiovascular-related conditions (>60%); however, only a small percentage (<8%) of total readmissions were for acute myocardial infarction, unstable angina, or cardiac arrest/cardiogenic shock. A much larger percentage of patients were readmitted with chest pain/angina (7.9%), chronic ischemic heart disease (26.6%), and heart failure (12%). A small proportion was due to procedural complications and gastrointestinal (GI) bleeding. The use of PCI with stenting during readmissions was variable, increasing from 14.2% in 2000 to 23.7% in 2006 and then declining to 12.1% in 2012. Hospital mortality during readmission was 2.5% overall and varied over time (2.8% in 2000, decreasing to 2.2% in 2006 and then rising again to 3.1% in 2012). Patients who were readmitted had >4× higher 30-day mortality than those who were not. CONCLUSIONS Among Medicare beneficiaries, readmission after PCI declined over time despite patients having more comorbidities. This translated into a 33% lower likelihood of readmission in 2012 compared with 2000. A small proportion of readmissions were for acute coronary syndromes.

Collaboration


Dive into the Christina M. Vassileva's collaboration.

Top Co-Authors

Avatar

Stephen R. Hazelrigg

Southern Illinois University School of Medicine

View shared research outputs
Top Co-Authors

Avatar

Stephen Markwell

Southern Illinois University School of Medicine

View shared research outputs
Top Co-Authors

Avatar

Theresa M. Boley

Southern Illinois University School of Medicine

View shared research outputs
Top Co-Authors

Avatar

Christian McNeely

Southern Illinois University School of Medicine

View shared research outputs
Top Co-Authors

Avatar

Steve Markwell

Southern Illinois University School of Medicine

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge