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Thornhill, M H

0000-0003-0681-4083

Mayo Clinic

Unit of Oral & Maxillofacial Medicine Surgery and Pathology, School of Clinical Dentistry, University of Sheffield, Sheffield, UK.

Citations 17

The endocarditis team: a review
Maher, Aoife, Baddour, Larry M., Dalati, Sami El, Miro, Jose M., DeSimone, Daniel C., Martí-Carvajal, Arturo J , Thornhill, Martin H. , Thornhill, M H , Baddour, Larry M. , El-Dalati, Sami A , Miro, Jose M., DeSimone, Daniel C. , Martí-Carvajal, Arturo José , Dayer, Mark

Expert Review of Anti-infective Therapy | June 25, 2026 | Volume: No volume available | Issue: No issue available | Pages: 1-12

10.1080/14787210.2026.2695437 Get It

Echocardiographic findings and subsequent risk of native valve endocarditis
Quintero-Martinez, Juan Andres , Villarraga, Hector R. , Lahr, Brian D. , Thornhill, Martin H. , Anavekar, Nandan S., Thornhill, M H , Quintero-Martinez, Juan A , Hindy, Joya-Rita , Dayer, Mark , O’Horo, John C. , Michelena, Héctor I. , Sendi, Parham , DeSimone, Daniel C. , Baddour, Larry M.

Exploration of Cardiology | September 25, 2024 | Volume: 2 | Issue: 5 | Pages: 204-216

10.37349/ec.2024.00034 Get It

Aim: The association of echocardiographic findings and subsequent risk of left-sided native valve endocarditis (LS-NVE) is undefined. The aim of this study was to determine if transthoracic echocardiography (TTE) measurements are associated with the subsequent development of LS-NVE in patients without cardiac predisposing conditions. Methods: Institutional databases were evaluated for adults diagnosed with LS-NVE from 2008 to 2020. Patients with prosthetic valves, cardiovascular implantable electronic devices, intracardiac devices, injection drug use, and predisposing cardiac conditions were excluded. Only patients who had a TTE performed 6 months to 3 years before the development of LS-NVE were included as cases. Controls were patients within the same Mayo location with a TTE report and were matched in a 1:3 ratio according to age, gender, Charlson comorbidity index, and echocardiography date. Results: There were 148 cases and 431 matched controls. As compared to controls, infective endocarditis (IE) cases had a higher prevalence of diabetes mellitus (46.6% vs. 30.4%) and chronic kidney disease (46.6% vs. 28.1%) (P < 0.001). Left ventricular outflow tract velocity (P = 0.017), left ventricular ejection fraction (P = 0.018), and E:e’ ratio (P = 0.050) were associated with LS-NVE. Conclusions: Echocardiographic measurements were associated with subsequent LS-NVE development in this pilot study. A larger cohort of LS-NVE patients, however, is needed to validate these findings.
Abstract 12875: Echocardiographic Findings Associated With Subsequent Risk of Native Valve Endocarditis
Martinez, Juan A Quintero, Villarraga, Hector R. , Lahr, Brian D. , Thornhill, Martin H. , Anavekar, Nandan S., Thornhill, M H , Hindy, Joya-Rita , Dayer, Mark , O’Horo, John C. , Michelena, Héctor I. , Sendi, Parham , DeSimone, Daniel C. , Baddour, Larry M.

Circulation | December 19, 2023 | Volume: 148 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.148.suppl_1.12875 Get It

Introduction: The association of echocardiographic measurements and subsequent risk of left-sided native valve endocarditis (LS-NVE) is undefined. Aim: To determine if transthoracic echocardiographic (TTE) measurements are associated with the subsequent development of LS-NVE in patients without recognized cardiac predisposing conditions. Methods: Institutional databases were evaluated for adults diagnosed with LS-NVE from 2008 to 2020. Patients with prosthetic valves, cardiovascular implantable electronic devices, intracardiac devices, injection drug use, and recognized predisposing cardiac conditions were excluded. Patients with a TTE performed 6 months to 3 years before developing LS-NVE were included as cases. Controls were patients within the same Mayo Clinic location with a TTE report and were matched in a 1:3 ratio according to age, gender, Charlson Comorbidity Index (CCI), and echocardiography date. Multivariate logistic-regression analyses adjusting significant variables between cohort's were performed. A p-value <0.05 was considered significant. Results: There were 148 cases and 431 matched controls. The median age was 63.8 (IQR: 53.6 - 74.6) years, and 329 (56.8%) patients were males. LS-NVE cases had a higher prevalence of diabetes mellitus (46.6% vs. 30.4%) and chronic kidney disease (46.6% vs. 28.1%) when compared with controls (p<0.001 both). The median CCI score was 3 (IQR: 0-6) for cases and 2 (IQR: 0-6) for controls. After performing adjusted analyses, left ventricular outflow tract velocity (p=0.017), left ventricular ejection fraction (p=0.018), and E: e’ ratio (p=0.050) were associated with the development of LS-NVE ( Figure 1) . Conclusions: Echocardiographic measurements were associated with subsequent LS-NVE development in this preliminary investigation. A larger cohort of LS-NVE patients is needed to validate these findings.
Endocarditis, invasive dental procedures, and antibiotic prophylaxis efficacy in US Medicaid patients
Thornhill, Martin H. , Gibson, Teresa B. , Yoon, Frank, Prendergast, Bernard , Lockhart, Peter B. , O’Gara, Patrick T. , O'Gara, Patrick T , Thornhill, M H , Dayer, Mark , Baddour, Larry M.

Oral Diseases | April 27, 2023 | Volume: 30 | Issue: 3 | Pages: 1591-1605

10.1111/odi.14585 Get It

Abstract Objective Antibiotic prophylaxis is recommended before invasive dental procedures to prevent endocarditis in those at high risk, but supporting data are sparse. We therefore investigated any association between invasive dental procedures and endocarditis, and any antibiotic prophylaxis effect on endocarditis incidence. Subjects and Methods Cohort and case‐crossover studies were performed on 1,678,190 Medicaid patients with linked medical, dental, and prescription data. Results The cohort study identified increased endocarditis incidence within 30 days of invasive dental procedures in those at high risk, particularly after extractions (OR 14.17, 95% CI 5.40–52.11, p < 0.0001) or oral surgery (OR 29.98, 95% CI 9.62–119.34, p < 0.0001). Furthermore, antibiotic prophylaxis significantly reduced endocarditis incidence following invasive dental procedures (OR 0.20, 95% CI 0.06–0.53, p < 0.0001). Case‐crossover analysis confirmed the association between invasive dental procedures and endocarditis in those at high risk, particularly following extractions (OR 3.74, 95% CI 2.65–5.27, p < 0.005) and oral surgery (OR 10.66, 95% CI 5.18–21.92, p < 0.0001). The number of invasive procedures, extractions, or surgical procedures needing antibiotic prophylaxis to prevent one endocarditis case was 244, 143 and 71, respectively. Conclusions Invasive dental procedures (particularly extractions and oral surgery) were significantly associated with endocarditis in high‐risk individuals, but AP significantly reduced endocarditis incidence following these procedures, thereby supporting current guideline recommendations.
Antibiotic Prophylaxis in Dentistry
Thornhill, Martin H. , Prendergast, Bernard , Lockhart, Peter B. , Baddour, Larry M. , Baddour, Larry , Thornhill, M H , Dayer, Mark

Clinical Infectious Diseases | November 22, 2022 | Volume: 76 | Issue: 5 | Pages: 960-961

10.1093/cid/ciac857 Get It

Temporal association between invasive procedures and infective endocarditis
Thornhill, Martin H. , Crum, Annabel , Campbell, Richard , Stone, Tony , Lee, Ellen , Bradburn, Mike , Fibisan, Veronica , Dayer, Mark , Prendergast, Bernard , Lockhart, Peter B. , Nicoll, Jon, Prendergast, Bernard D , Baddour, Larry , Thornhill, M H , Dayer, Mark J , Baddour, Larry M. , Stone, Tony

Heart | September 22, 2022 | Volume: 109 | Issue: 3 | Pages: 223-231

10.1136/heartjnl-2022-321519 Get It

Objective Antibiotic prophylaxis has been recommended for patients at increased risk of infective endocarditis (IE) undergoing specific invasive procedures (IPs) despite a lack of data supporting its use. Therefore, antibiotic prophylaxis recommendations ceased in the mid-2000s for all but those at high IE risk undergoing invasive dental procedures. We aimed to quantify any association between IPs and IE. Methods All 14 731 IE hospital admissions in England between April 2010 and March 2016 were identified from national admissions data, and medical records were searched for IP performed during the 15-month period before IE admission. We compared the incidence of IP during the 3 months immediately before IE admission (case period) with the incidence during the preceding 12 months (control period) to determine whether the odds of developing IE were increased in the 3 months after certain IP. Results The odds of IE were increased following permanent pacemaker and defibrillator implantation (OR 1.54, 95% CI 1.27 to 1.85, p<0.001), extractions/surgical tooth removal (OR 2.14, 95% CI 1.22 to 3.76, p=0.047), upper (OR 1.58, 95% CI 1.34 to 1.85, p<0.001) and lower gastrointestinal endoscopy (OR 1.66, 95% CI 1.35 to 2.04, p<0.001) and bone marrow biopsy (OR 1.76, 95% CI 1.16 to 2.69, p=0.039). Using an alternative analysis, bronchoscopy (OR 1.33, 95% CI 1.06 to 1.68, p=0.049) and blood transfusions/red cell/plasma exchange (OR 1.2, 95% CI 1.07 to 1.35, p=0.012) were also associated with IE. Conclusions This study identifies a significant association between specific IPs (permanent pacemaker and defibrillator implantation, dental extraction, gastrointestinal endoscopy and bronchoscopy) and subsequent IE that warrants re-evaluation of current antibiotic prophylaxis recommendations to prevent IE in high IE risk individuals.
Infective endocarditis following invasive dental procedures: IDEA case-crossover study
Thornhill, Martin H. , Crum, Annabel , Rex, Saleema , Campbell, Richard , Stone, Tony , Bradburn, Mike , Fibisan, Veronica , Dayer, Mark , Prendergast, Bernard , Lockhart, Peter B. , Nicholl, Jon , Dayer, Mark J , Prendergast, Bernard D , Baddour, Larry , Nicholl, Jon , Thornhill, M H , Stone, Tony , Baddour, Larry M.

Health Technology Assessment | June 1, 2022 | Volume: 26 | Issue: 28 | Pages: 1-86

10.3310/nezw6709 Get It

Background Infective endocarditis is a heart infection with a first-year mortality rate of ≈ 30%. It has long been thought that infective endocarditis is causally associated with bloodstream seeding with oral bacteria in ≈ 40–45% of cases. This theorem led guideline committees to recommend that individuals at increased risk of infective endocarditis should receive antibiotic prophylaxis before undergoing invasive dental procedures. However, to the best of our knowledge, there has never been a clinical trial to prove the efficacy of antibiotic prophylaxis and there is no good-quality evidence to link invasive dental procedures with infective endocarditis. Many contend that oral bacteria-related infective endocarditis is more likely to result from daily activities (e.g. tooth brushing, flossing and chewing), particularly in those with poor oral hygiene. Objective The aim of this study was to determine if there is a temporal association between invasive dental procedures and subsequent infective endocarditis, particularly in those at high risk of infective endocarditis. Design This was a self-controlled, case-crossover design study comparing the number of invasive dental procedures in the 3 months immediately before an infective endocarditis-related hospital admission with that in the preceding 12-month control period. Setting The study took place in the English NHS. Participants All individuals admitted to hospital with infective endocarditis between 1 April 2010 and 31 March 2016 were eligible to participate. Interventions This was an observational study; therefore, there was no intervention. Main outcome measure The outcome measure was the number of invasive and non-invasive dental procedures in the months before infective endocarditis-related hospital admission. Data sources NHS Digital provided infective endocarditis-related hospital admissions data and dental procedure data were obtained from the NHS Business Services Authority. Results The incidence rate of invasive dental procedures decreased in the 3 months before infective endocarditis-related hospital admission (incidence rate ratio 1.34, 95% confidence interval 1.13 to 1.58). Further analysis showed that this was due to loss of dental procedure data in the 2–3 weeks before any infective endocarditis-related hospital admission. Limitations We found that urgent hospital admissions were a common cause of incomplete courses of dental treatment and, because there is no requirement to record dental procedure data for incomplete courses, this resulted in a significant loss of dental procedure data in the 2–3 weeks before infective endocarditis-related hospital admissions. The data set was also reduced because of the NHS Business Services Authority’s 10-year data destruction policy, reducing the power of the study. The main consequence was a loss of dental procedure data in the critical 3-month case period of the case-crossover analysis (immediately before infective endocarditis-related hospital admission), which did not occur in earlier control periods. Part of the decline in the rate of invasive dental procedures may also be the result of the onset of illness prior to infective endocarditis-related hospital admission, and part may be due to other undefined causes. Conclusions The loss of dental procedure data in the critical case period immediately before infective endocarditis-related hospital admission makes interpretation of the data difficult and raises uncertainty over any conclusions that can be drawn from this study. Future work We suggest repeating this study elsewhere using data that are unafflicted by loss of dental procedure data in the critical case period. Trial registration This trial is registered as ISRCTN11684416. Funding This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 28. See the NIHR Journals Library website for further project information.
Escalating incidence of infective endocarditis in Europe in the 21st century
Talha, Khawaja M. , Thornhill, Martin H. , Arshad, Verda , Tariq, Wajeeha , Tleyjeh, Imad M, Scott, Christopher G. , Hyun, Meredith C, Bailey, Kent R. , Anavekar, Nandan S., Palraj, Raj , Tleyjeh, Imad M. , Scott, Christopher , Thornhill, M H , Tleyjeh, Imad M , Palraj, Raj , Baddour, Larry M. , Hyun, Meredith C, Sohail, M. Rizwan , DeSimone, Daniel C. , Dayer, Mark

Open Heart | October 20, 2021 | Volume: 8 | Issue: 2 | Pages: e001846

10.1136/openhrt-2021-001846 Get It

Aim To provide a contemporary analysis of incidence trends of infective endocarditis (IE) with its changing epidemiology over the past two decades in Europe. Methods A systematic review was conducted at the Mayo Clinic, Rochester. Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus and Web of Science were searched for studies published between 1 January 2000 and 30 November 2020. All studies were independently reviewed by four referees and those that included a population-based incidence of IE in patients, irrespective of age, in Europe were included. Least squares regression was used to estimate pooled temporal trends in IE incidence. Results Of 9138 articles screened, 18 studies were included in the review. Elderly men predominated in all studies. IE incidence increased 4.1% per year (95% CI 1.8% to 6.4%) in the pooled regression analysis of eight studies that included comprehensive and consistent trends data. When trends data were weighted according to population size of individual countries, an increase in yearly incidence of 0.27 cases per 100 000 people was observed. Staphylococci and streptococci were the most common pathogens identified. The rate of surgical intervention ranged from 10.2% to 60.0%, and the rate of inpatient mortality ranged from 14.3% to 17.5%. In six studies that examined the rate of injection drug use, five of them reported a rate of less than 10%. Conclusion Based on findings from our systematic review, IE incidence in Europe has doubled over the past two decades in Europe. Multiple factors are likely responsible for this striking increase. Trial registeration number CRD42020191196.
Temporal Trends of Infective Endocarditis in North America From 2000 to 2017—A Systematic Review
Talha, Khawaja M. , Thornhill, Martin H. , Tariq, Wajeeha , Arshad, Verda , Tleyjeh, Imad M, Bailey, Kent R. , Palraj, Raj , Anavekar, Nandan S., Tleyjeh, Imad M. , DeSimone, Daniel C , Thornhill, M H , Tleyjeh, Imad M , Palraj, Raj , Dayer, Mark , Sohail, M. Rizwan , DeSimone, Daniel C. , Baddour, Larry M.

Open Forum Infectious Diseases | September 25, 2021 | Volume: 8 | Issue: 11 | Pages: No page available

10.1093/ofid/ofab479 Get It

Abstract Background The objective of this paper was to examine temporal changes of infective endocarditis (IE) incidence and epidemiology in North America. Methods A systematic review was conducted at Mayo Clinic, Rochester. Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science were searched for studies published between January 1, 2000, and May 31, 2020. Four referees independently reviewed all studies, and those that reported a population-based incidence of IE in patients aged 18 years and older in North America were included. Results Of 8588 articles screened, 14 were included. Overall, IE incidence remained largely unchanged throughout the study period, except for 2 studies that demonstrated a rise in incidence after 2014. Five studies reported temporal trends of injection drug use (IDU) prevalence among IE patients with a notable increase in prevalence observed. Staphylococcus aureus was the most common pathogen in 7 of 9 studies that included microbiologic findings. In-patient mortality ranged from 3.7% to 14.4%, while the percentage of patients who underwent surgery ranged from 6.4% to 16.0%. Conclusions The overall incidence of IE has remained stable among the 14 population-based investigations in North America identified in our systematic review. Standardization of study design for future population-based investigations has been highlighted for use in subsequent systematic reviews of IE.