Katherine S. King

Natural history and clinical detection of undiagnosed coeliac disease in a North American community

Coeliac disease is a substantially underdiagnosed disorder, with clinical testing currently guided by case finding.

Transfemoral transcatheter aortic valve insertion-related intraoperative morbidity: Implications of the minimalist approach

OBJECTIVES Transfemoral transcatheter aortic valve insertion may be performed in a catheterization laboratory (ie, the minimalist approach). It seems reasonable when considering this approach to avoid it in patients at risk for intraoperative morbidity that would require surgical intervention. We hypothesized that it would be possible to associate baseline characteristics with such morbidity, which would help heart teams select patients for the minimalist approach. METHODS We reviewed the records of 215 consecutive patients who underwent transfemoral transcatheter aortic valve insertion with a current commercially available device from November 2008 through July 2015. Demographic characteristics of the patients included a mean age of 78.9 ± 10.6 years, female sex in 73 patients (34.0%), and a mean Society of Thoracic Surgeons predicted risk of mortality of 8.7% ± 5.4%. Valve prostheses were balloon-expandable in 126 patients (58.6%) and self-expanding in 89 patients (41.4%). RESULTS Significant intraoperative morbidity occurred in 22 patients (10.2%) and included major vascular injury in 12 patients (5.6%), hemodynamic compromise requiring cardiopulmonary bypass support in 4 patients (1.9%), cardiac tamponade requiring intervention in 3 patients (1.4%), ventricular valve embolization in 2 patients (0.9%), and inability to obtain percutaneous access requiring open vascular access in 1 patient (0.5%). Intraoperative morbidity was similarly distributed across all valve types (P = .556) and sheath sizes (P = .369). There were no baseline patient characteristics predictive of intraoperative morbidity. CONCLUSIONS Patient and valve characteristics are not predictive of significant intraoperative morbidity during transfemoral transcatheter aortic valve insertion. The finding has implications for patient selection for the minimalist approach.

Increasing Incidence and Altered Presentation in a Population-based Study of Pediatric Celiac Disease in North America

Objectives: Celiac disease (CD) is a common immune-mediated disorder that affects up to 1% of the general population. Recent reports suggest that the incidence of CD has reached a plateau in many countries. We aim to study the incidence and altered presentation of childhood CD in a well-defined population. Methods: Using the Rochester Epidemiology Project, we retrospectively reviewed Mayo Clinic and Olmsted Medical Center medical records from January 1994 to December 2014. We identified all CD cases of patients ages 18 years or younger at the time of diagnosis. Incidence rates were calculated by adjusting for age, sex, and calendar year and standardizing to the 2010 US white population. Results: We identified 100 patients with CD. Incidence of CD has increased from 8.1 per 100,000 person-years (2000–2002) to 21.5 per 100,000 person-years (2011–2014). There was an increase in CD prevalence in children from 2010 (0.10%) to 2014 (0.17%). Thirty-four patients (34%) presented with classical CD symptoms, 43 (43%) had nonclassical CD, and 23 (23%) were diagnosed by screening asymptomatic high-risk patients. Thirty-six patients (36%) had complete villous atrophy, 51 (51%) had partial atrophy, and 11 (11%) had increased intraepithelial lymphocytes. Two patients were diagnosed without biopsy. Most patients (67%) had a normal body mass index, 17% were overweight/obese, and only 9% were underweight. Conclusions: Both incidence and prevalence of CD have continued to increase in children during the past 15 years in Olmsted County, Minnesota. Clinical and pathologic presentations of CD are changing over time (more nonclassical and asymptomatic cases are emerging).

What accounts for the association between late preterm births and risk of asthma

BACKGROUND Although results of many studies have indicated an increased risk of asthma in former late preterm (LPT) infants, most of these studies did not fully address covariate imbalance. OBJECTIVE To compare the cumulative frequency of asthma in a population-based cohort of former LPT infants to that of matched term infants in their early childhood, when accounting for covariate imbalance. METHODS From a population-based birth cohort of children born 2002-2006 in Olmsted County, Minnesota, we assessed a random sample of LPT (34 to 36 6/7 weeks) and frequency-matched term (37 to 40 6/7 weeks) infants. The subjects were followed-up through 2010 or censored based on the last date of contact, with the asthma status based on predetermined criteria. The Kaplan-Meier method was used to estimate the cumulative incidence of asthma during the study period. Cox models were used to estimate the hazard ratio and 95% confidence interval for the risk of asthma, when adjusting for potential confounders. RESULTS LPT infants (n = 282) had a higher cumulative frequency of asthma than did term infants (n = 297), 29.9 versus 19.5%, respectively; p = 0.01. After adjusting for covariates associated with the risk of asthma, an LPT birth was not associated with a risk of asthma, whereas maternal smoking during pregnancy was associated with a risk of asthma. CONCLUSION LPT birth was not independently associated with a risk of asthma and other atopic conditions. Clinicians should make an effort to reduce exposure to smoking during pregnancy as a modifiable risk factor for asthma.

Predictors of 1-year mortality after transcatheter aortic valve replacement

To identify variables predictive of increased mortality within 1 year of transcatheter aortic valve replacement (TAVR).

Transcatheter aortic valve insertion after previous mitral valve operation

Objective: There are limited data on transcatheter aortic valve insertion after previous mitral valve operation. To better understand the associated procedural risks, we reviewed our single‐center experience. Methods: We retrospectively reviewed the records of 772 consecutive patients who received transcatheter aortic valve insertion from November 2008 through August 2016. There were 18 (2%) patients who had previous mitral valve operation that included valve repair in 4 patients (22%) and replacement in 14 (78%). Results: Baseline characteristics included age of 77 years (interquartile range 68, 84), female sex in 11 patients (61%), New York Heart Association functional class III/IV in 14 (78%), and Society of Thoracic Surgeons predicted risk of mortality of 7.0% (5.3, 12.0). Access was transfemoral in 14 patients (78%). Valve insertion was successful in all patients and involved a balloon expandable device in 10 (56%). No patient experienced acute mitral valve dysfunction or procedure‐related mortality. Follow‐up echocardiography demonstrated mean systolic aortic valve gradient of 9 mm Hg (8, 12), no grade moderate or greater aortic paravalvular regurgitation, and stable mitral valve function. Kaplan‐Meier estimated survival was 90.9% ± 9.1% at 1 year. Conclusions: Transcatheter aortic valve insertion appears to be a safe and effective operation after previous mitral valve operation. Procedure success was achieved with both balloon expandable and self‐expanding devices and was independent of arterial access method. Transcatheter valve insertion should not be denied strictly on the basis of a previous mitral valve operation.

The influence of native aortic valve calcium and transcatheter valve oversize on the need for pacemaker implantation after transcatheter aortic valve insertion

Objective: Native aortic valve calcium and transcatheter aortic valve oversize have been reported to predict pacemaker implantation after transcatheter aortic valve insertion. We reviewed our experience to better understand the association. Methods: We retrospectively reviewed the records of 300 patients with no prior permanent pacemaker implantation who underwent transcatheter aortic valve insertion from November 2008 to February 2015. Valve oversize was calculated using area. The end point of the study was 30‐day postoperative pacemaker implantation. Results: Patient data included age of 81.1 ± 8.4 years, female sex in 135 patients (45%), atrial fibrillation in 74 patients (24.7%), Society of Thoracic Surgeons predicted risk of mortality of 7.6% (interquartile range [IQR], 5.3‐10.6), aortic valve calcium score of 2568 (IQR, 1775‐3526) Agatston units, and annulus area of 471 ± 82 mm2. Balloon‐expandable valves were inserted in 244 patients (81.3%). Transcatheter aortic valve oversize was 12.8% (IQR, 3.9‐23.3). Pacemaker implantation was performed in 59 patients (19.7%). Aortic valve calcium score (adjusted P = .275) and transcatheter valve oversize (adjusted P = .833) were not independent risk factors for pacemaker implantation when controlling for preoperative right bundle branch block (adjusted odds ratio, 3.49; 95% confidence interval, 1.61‐8.55; P = .002), implantation of self‐expanding valve (adjusted odds ratio, 4.09; 95% confidence interval, 1.53‐10.96; P = .005), left bundle branch block (adjusted P = .331), previous percutaneous coronary intervention (adjusted P = .053), or valve surgery (adjusted P = .111), and PR interval (adjusted P = .350). Conclusions: Right bundle branch block and implantation of a self‐expanding prosthesis were predictive of pacemaker implantation, but not native aortic valve score or transcatheter valve oversize.

Outcome of Tricuspid Valve Surgery in the Presence of Permanent Pacemaker

Objectives: Given the paucity of available literature, we sought to evaluate the mechanisms of tricuspid regurgitation and the outcomes of tricuspid valve surgery in the presence of permanent pacemakers. Methods: We retrospectively reviewed the records of 622 adult patients who underwent tricuspid valve surgery in the presence of permanent pacemakers between January 1993 and December 2013. Those with prosthetic tricuspid valve or tricuspid valve endocarditis and those undergoing concomitant heart transplant were excluded (n = 23). Patients were divided into 2 etiologic groups: pacemaker‐associated tricuspid regurgitation (n = 349, 58%) and pacemaker‐induced tricuspid regurgitation (n = 249, 42%). One patient was not categorized, because permanent pacemaker involvement was unknown. Results: Mean age was 69.5 ± 12.0 years; 312 patients (52%) were female. In pacemaker‐associated tricuspid regurgitation, the most common cause was functional (n = 304, 87%). The most common mechanism leading to pacemaker‐induced tricuspid regurgitation was restricted leaflet mobility (n = 101, 41%), followed by adherent leaflet to the leads (n = 93, 37%), leaflet perforation (n = 30, 12%), scarring of leaflets (n = 19, 8%), and chordal entrapment (n = 18, 7%). The most common leaflet involved was septal leaflet (n = 182, 73%). Tricuspid valve repair (n = 215, 62%) was higher in the pacemaker‐associated tricuspid regurgitation group. In multivariable analysis, pacemaker‐induced tricuspid regurgitation was found to be protective with improved survival (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.68‐0.98). Other independent risk factors of mortality included tricuspid valve replacement (HR, 1.50; 95% CI, 1.20‐1.87), nonelective surgery (HR, 1.66; 95% CI, 1.33‐2.08), diabetes (HR, 1.37; 95% CI, 1.09‐1.73), severe tricuspid regurgitation (HR, 1.42; 95% CI, 1.04‐1.95), and older age when there was a concomitant aortic valve surgery (HR, 1.44; 95% CI, 1.15‐1.79). Conclusions: Several mechanisms lead to pacemaker‐induced tricuspid regurgitation. Pacemaker‐induced tricuspid regurgitation when compared with pacemaker‐associated tricuspid regurgitation carries a better prognosis with improved survival.

Aortic valve replacement in patients with amyloidosis

Background: Outcome data on aortic valve replacement in patients with amyloidosis are limited. To address this issue, we reviewed our experience of patients with amyloidosis who underwent aortic valve replacement. Methods: We retrospectively reviewed the records of 16 patients with amyloidosis who underwent aortic valve replacement between May 2000 and February 2017. Results: The cohort comprised 11 males (69%) and 5 females (31%). The median patient age was 76 years (interquartile range [IQR], 71‐82 years), and Society of Thoracic Surgeons predicted rate of mortality was 5.0% (IQR, 2.4%‐8.7%). Amyloidosis type was immunoglobulin light chain in 6 patients (38%), age‐related in 6 (38%), and localized in 4 (25%). The operation was surgical aortic valve replacement in 11 patients (69%) and balloon‐expandable transfemoral transcatheter aortic valve insertion in the other 5. There was no procedure‐related stroke, need for new‐onset dialysis or pacemaker, or death within 30 days of surgery. The median length of hospital stay was 1 day (IQR, 1‐2 days) in the transcatheter valve insertion group and 6 days (IQR, 6‐8 days) in the surgical group (P = .002). Follow‐up was available for all patients at a median of 1.9 years (IQR, 1.2‐4.8 years). During the follow‐up period, there were 4 deaths, all occurring >1 year after surgery. Conclusions: Aortic valve replacement can be performed with low risk of operative morbidity and mortality in patients with amyloidosis. Transcatheter valve insertion has the advantage of reduced hospital length of stay. The 1‐year survival is excellent.

Undetectable negative tissue transglutaminase IgA antibodies predict mucosal healing in treated coeliac disease patients

Tissue transglutaminase (tTG) immunoglobulin A (IgA) testing is a sensitive adjunct to the diagnosis of coeliac disease. The threshold for positivity was developed for diagnosis, with negative results reported as below the reference value (<4 U/mL).