The QT interval in clinical hypercalcemia

Corrected QT intervals were determined in 13 patients with severe, chronic hypercalcemia. The Q_OT_C interval was short in only 2 of 14 instances; Q_AT_C in 5 of 15 instances, and Q_ET_C in 5 of 16 instances. The correlations between serum calcium and the QT_C measurement were not significant when evaluating either linear or curvilinear (quadratic) relationships. Small and inconsistent changes were found when comparing the QT intervals before the development of the hypercalcemic episode, during hypercalcemia, or after successful treatment. We conclude that shortening of the QT interval is an unreliable index of clinical (chronic) hypercalcemia.     

The Utility of Rapid Atrial Pacing Immediately Post-TAVR to Predict the Need for Pacemaker Implantation

ObjectivesThe aim of this study was to determine the utility of rapid atrial pacing immediately after transcatheter aortic valve replacement (TAVR) to predict the need for permanent pacemaker implantation (PPI).BackgroundRisk stratification for patients without high-grade atrioventricular block (AVB) after TAVR is imprecise and based on anatomic considerations, electrocardiographic characteristics, and clinical suspicion. A more reliable assessment is necessary to minimize inpatient rhythm monitoring and/or reduce unnecessary PPI.MethodsConsecutive patients undergoing TAVR at 2 centers were included. After valve implantation in patients without pacemakers who did not have complete heart block or atrial fibrillation, the temporary pacemaker was withdrawn from the right ventricle and placed in the right atrium. Rapid atrial pacing was performed from 70 to 120 beats/min, and patients were assessed for the development of Wenckebach AVB. Patients were then followed for clinical outcomes, including PPI.ResultsA total of 284 patients were included. Of these, 130 (45.8%) developed Wenckebach AVB. There was a higher rate of PPI within 30 days of TAVR among the patients who developed Wenckebach AVB (13.1% vs. 1.3%; p < 0.001), with a negative predictive value for PPI in the group without Wenckebach AVB of 98.7%. A greater percentage of patients receiving self-expanding valves required PPI than those receiving a balloon-expandable valves (15.9% vs. 3.7%; p = 0.001), though these rates were still relatively low among patients who did not develop Wenckebach AVB (2.9% and 0.8%).ConclusionsAtrial pacing post-TAVR is easily performed and can help identify patients who may benefit from extended rhythm monitoring. Patients who did not develop pacing-induced Wenckebach AVB demonstrated an extremely low likelihood of PPI.     

Implementation of cancer prevention guidelines in clinical practice

Data from several sources, including consumer surveys, physician surveys, and medical record audits, indicate that consumers do not receive cancer screening tests as recommended by the National Cancer Institute, the American Cancer Society, and the U.S. Preventive Services Task Force. Performance rates are consistently below published standards for all tests except Pap tests. Major reasons physicians do not perform the recommended tests include physician forgetfulness, disagreement with recommendations, lack of time, and patient refusal. Physicians also tend to overestimate their own performance rates. Barriers to screening test performance can be categorized into patient factors, physician factors, test factors, and health care delivery system factors. Interventions, such as computerized reminder systems, physician audits with feedback, and patient education and reminders, can be effective in promoting performance of such screening. Interventions that target both physician and patient may be particularly effective. Presented at the conference, Frontiers in Disease Prevention, The Johns Hopkins University, June 5–6, 1989.     

Molecular screening of the glucokinase gene in familial Type 2 (non-insulin-dependent) diabetes mellitus

Summary The glucokinase locus has been implicated by linkage studies in several Caucasian pedigrees with early onset, autosomal dominant diabetes, and mutations have been identified in a large number of these pedigrees. Although mutations have been reported in some pedigrees with late onset Type 2 (non-insulin-dependent) diabetes mellitus, linkage studies of typical familial Type 2 diabetes did not suggest a major role for this locus. Nonetheless, linkage studies were consistent with the hypothesis that mutations of the glucokinase gene were responsible for the pathogenesis of Type 2 diabetes in a minority of pedigrees or one gene in a polygenic disorder. To systematically address this hypothesis, we examined 60 diabetic members of 18 pedigrees ascertained for two or more Type 2 diabetic siblings and eight unrelated diabetic spouses. Initially, the coding regions from each of the 11 glucokinase exons were examined by the sensitive technique of single strand conformation polymorphism analysis to screen for single nucleotide substitutions. Subsequently, we also sequenced each exon from an affected member of the single pedigree in which a glucokinase allele was most likely to segregate with diabetes. Single strand conformation polymorphism analysis detected only three variants, none of which altered the amino acid sequence. No coding or splice site mutations were detected. Likewise, no additional mutations were detected upon direct sequence analysis. However, additional screening of promoter and 3′ untranslated regions detected a variant pattern in the untranslated region of exon 10 which appeared to segregate with diabetes and impaired glucose tolerance in one pedigree. Sequence analysis demonstrated the deletion of a cytosine in exon 10 at position 906, but this deletion was not associated with Type 2 diabetes among unrelated spouses, was not linked to diabetes, and was not associated with significant elevations of fasting glucose or insulin among non-diabetic pedigree members. Similarly, two common variants in the islet promoter did not segregate with diabetes. We conclude that among typical familial Type 2 diabetes in a population representative of Northern European Caucasians, glucokinase mutations are an unlikely cause of diabetes. [Diabetologia (1994) 37: 182–187] Received: 10 June 1993 and in revised form: 20 August 1993     

Balloon Aortic Valvuloplasty as a Bridge to Aortic Valve Replacement: A Contemporary Nationwide Perspective

ObjectivesThis study sought to use a national representative database to assess the incidence, predictors, and outcomes of balloon aortic valvuloplasty (BAV) as a bridge to transcatheter aortic valve replacement (TAVR) in contemporary practice.BackgroundNationwide data on the use and outcomes of BAV as a bridge to TAVR are limited.MethodsPatients who underwent BAV between January and June in 2015 and 2016 were identified in the National Readmission Database. We assessed rate of subsequent TAVR following BAV, and predictors and timing of subsequent TAVR. We then identified a group of patients who had direct TAVR (without prior BAV) in the original 2015 to 2016 National Readmission Database dataset. We compared in-hospital outcomes following TAVR between patients with prior bridging BAV and those undergoing direct TAVR.ResultsAmong the 3,691 included patients 1,426 (38.6%) had subsequent TAVR. Timing of TAVR was pre-discharge in 7.4%, within 30 days in 35%, between 31 and 90 days in 47%, between 91 and 180 days in 14%, and >180 days in 4%. Negative predictors of subsequent TAVR included prior defibrillator (odds ratio [OR]: 0.56; 95% confidence interval [CI]: 0.36 to 0.85), dementia (OR: 0.60; 95% CI: 0.46 to 0.79), malnutrition (OR: 0.64; 95% CI: 0.45 to 0.90), and malignancy (OR: 0.62; 95% CI: 0.47 to 0.82). In propensity-score matched cohorts of patients who underwent direct TAVR versus those with prior BAV, in-hospital mortality during TAVR admission was similar (3.7% vs. 3.5%; p = 0.91). Major complications, length of stay, and discharge disposition were also comparable. However, cost of the hospitalization was higher in the direct TAVR group.ConclusionsAbout 40% of BAV patients undergo subsequent TAVR mostly within 90 days. In-hospital outcomes of TAVR in these patients were comparable with propensity-score matched patients who underwent TAVR without prior BAV. Further investigations are needed to define the role of BAV in contemporary practice.     

Changes in house design reduce exposure to malaria mosquitoes

House design may affect an individual's exposure to malaria parasites, and hence to disease. We conducted a randomized-controlled study using experimental huts in rural Gambia, to determine whether installing a ceiling or closing the eaves could protect people from malaria mosquitoes. Five treatments were tested against a control hut: plywood ceiling; synthetic-netting ceiling; insecticide-treated synthetic-netting ceiling (deltamethrin 12.5 mg/m2); plastic insect-screen ceiling; or the eaves closed with mud. The acceptability of such interventions was investigated by discussions with local communities. House entry by Anopheles gambiae, the principal African malaria vector, was reduced by the presence of a ceiling: plywood (59% reduction), synthetic-netting (79%), insecticide-treated synthetic-netting (78%), plastic insect-screen (80%, P < 0.001 in all cases) and closed eaves (37%, ns). Similar reductions were also seen with Mansonia spp., vectors of lymphatic filariasis and numerous arboviruses. Netting and insect-screen ceilings probably work as decoy traps attracting mosquitoes into the roof space, but not the room. Ceilings are likely to be well accepted and may be of greatest benefit in areas of low to moderate transmission and when used in combination with other malaria control strategies.     

Predictors of failure to attend scheduled mammography appointments at a Public Teaching Hospital

Objective: To identify patient, institutional, and physician characteristics that predict failure to attend scheduled mammography appointments. Design: Retrospective chart review. Setting: Medicine clinic at an urban public teaching hospital. Patients: All 907 women aged 40 years and more scheduled for mammography from March 1990 to June 1991. Measurements and main results: The main outcome measure was whether a woman kept her scheduled mammography appointment. Potential predictor variables included patient age, race, marital status, and insurance status; waiting interval to obtain a mammography appointment; and physician gender, level of training, country of training, and native language. The rate of failed mammography appointments was 23%. Univariate analysis showed that appointment failure was associated with age (p=0.03), with the lowest failure rates (19%) among women aged 60 years and more. Appointment keeping varied significantly by race (p=0.01), largely because of the higher failure rate among Native American women (36%). Insured women had a failure rate of 22% vs 33% for uninsured women (p=0.01). The rate of failed appointments varied significantly by waiting interval (p=0.05), with a peak failure rate of 27% for appointments scheduled 14–27 days in advance. None of the physician variables was associated with appointment failure. Multivariate analysis confirmed these results. Conclusions: Interventions to improve completion of breast cancer screening should include additional efforts targeted at groups with high rates of appointment failure, such as women under the age of 60, the uninsured, and Native Americans. Long waiting intervals to obtain mammography appointments may decrease compliance. Presented in part at the annual meeting of the Society of General Internal Medicine, Washington, DC, April 30, 1992. Supported by research grant CA 52994 from the National Cancer Institute, Bethesda, Maryland. Dr. Margolis was supported by an American Cancer Society Cancer Control Career Development Award for Primary Care Physicians. Dr. Lurie is a Henry J. Kaiser Family Foundation Scholar in General Internal Medicine.     

Solid‐phase extraction–liquid chromatography–tandem mass spectrometry method for the qualitative analysis of 61 synthetic cannabinoid metabolites in urine

This article comprises the development and validation of a protocol for the qualitative analysis of 61 phase I synthetic cannabinoid metabolites in urine originating from 29 synthetic cannabinoids, combining solid‐phase extraction (SPE) utilizing a reversed phase silica‐based sorbent (phenyl) with liquid chromatography–tandem mass spectrometry (LC?MS/MS). Validation was performed according to the guidelines of the German Society of Toxicological and Forensic Chemistry. Sufficient chromatographic separation was achieved within a total runtime of 12.3 minutes. Validation included specificity and selectivity, limit of detection (LOD), recovery and matrix effects, as well as auto‐sampler stability of processed urine samples. LOD ranged between 0.025 ng/mL and 0.5 ng/mL in urine. Recovery ranged between 43% and 97%, with only two analytes exhibiting recoveries below 50%. However, for those two analytes, the LODs were 0.05 ng/mL in urine. In addition, matrix effects between 81% and 185% were determined, whereby matrix effects over 125% were observed for 10 non‐first‐generation synthetic cannabinoid metabolites. The developed method enables the rapid and sensitive detection of synthetic cannabinoid metabolites in urine, complementing the spectrum of existing analytical tools in forensic case work. Finally, application to 61 urine samples from both routine and autopsy case work yielded one urine sample that tested positive for ADB‐PINACA N‐pentanoic acid.