Late stent thrombosis as a complication of T and small protrusion bifurcation stenting: a case report.

Background: A case of stent thrombosis as a complication of coronary bifurcation stenting is described. We review potential complications of bifurcation stenting and established guidelines. Case summary: A 64-year-old man presented with a non-ST segment elevation myocardial infarction. High-sensitivity troponin I peaked at 99 000 ng/L (normal <5). He previously had coronary stenting for stable angina when residing in another country 2 years previously. Coronary angiography revealed no significant stenosis with TIMI 3 flow in all vessels. Cardiac magnetic resonance imaging demonstrated a left anterior descending artery (LAD) territory regional motion abnormality, late gadolinium enhancement consistent with recent infarction, and a left ventricular apical thrombus. Repeat angiography and intravascular ultrasound (IVUS) confirmed bifurcation stenting at the junction of the LAD and second diagonal (D2) with protrusion of several millimetres of the uncrushed proximal segment of the D2 stent in the LAD vessel lumen. There was under-expansion of the LAD stent in the mid-vessel and stent malapposition in the proximal LAD, extending into the distal left main stem coronary artery and involving the ostium of the left circumflex coronary artery. Percutaneous balloon angioplasty was performed along the length of the stent, including an internal crush of the D2 stent. Coronary angiography confirmed a uniform expansion of the stented segments and TIMI 3 flow. Final IVUS confirmed full stent expansion and apposition. Discussion: This case highlights the importance of provisional stenting as a default strategy and familiarity with procedural steps in bifurcation stenting. Furthermore, it emphasizes the benefit of intravascular imaging for lesion characterization and stent optimization.

Technologies for teaching during a pandemic.

The coronavirus pandemic has had a major impact on education. As a result of this crisis, instructors world-wide had to quickly adapt and shift to remote teaching. This paper presents and describes technologies (such as Microsoft Teams, Zoom, Virtual Worlds, etc.) to promote active student learning during a pandemic. It also provides general information about the coronavirus and the learning environment that it created.

Rotation Disk Process to Assess the Influence of Metals and Voltage on the Growth of Biofilm.

Biofilms consist of not only bacteria but also extracellular polymer substrates (EPS). They are groups of microorganisms that adhere to each other on a surface, especially as a result of exposure to water and bacteria. They can pose health risks to humans as they grow in hospital settings that include medical supplies and devices. In a previous study, the researchers discovered that bacteria/biofilm grew well on wetted external latex, male catheters. These results concerned the investigators and encouraged them to find ways for prohibiting the growth of bacteria/biofilm on the male catheters (which are made of natural rubber). They carried out a new study to assess the influence of metals and voltage for the growth of bacteria on these latex samples. For this purpose, a unique Rotation Disk Reactor was used to accelerate biofilm formation on external male catheter samples. This setup included a dip tank containing water and a rotating wheel with the attached latex samples (some of which had single electrodes while others had paired electrodes with applied voltage). The process allowed the samples to become wetted and also exposed them to microorganisms in the ambient air during each revolution of the wheel. The results (as viewed from SEM images) showed that when compared to the control sample, the presence of metals (brass, stainless steel, and silver) was generally effective in preventing bacterial growth. Also the use of voltage (9.5 volt battery) essentially eliminated the appearance of rod shaped bacteria in some of the samples. It can be concluded that the presence of metals significantly reduced bacterial growth on latex and the application of voltage was able to essentially eliminate bacteria, providing appropriate electrode combinations were used.

10-year follow-up of patients with and without mediastinitis.

Mediastinitis is a dreaded complication of CABG surgery. Short-term outcomes have been described, but there have been only a few long-term studies. We examined the survival of patients undergoing isolated CABG surgery between 1992 and 2001. Mediastinitis was identified during the index admission. Proportional hazards regression was used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (CI 95%). Among 36,078 consecutive patients, there were 5749 deaths during 148,319 person years of follow-up. There were 418 cases of mediastinitis (1.16%). The incidence of death was 11.15 per 100 person/years with mediastinitis and 3.81 deaths/100 person years without. (P < 0.001). We also examined the mortality rates of patients who survived at least 6 months after their CABG surgery. Patients with mediastinitis had an incidence rate of 5.70 deaths per 100 person/years while those without had a rate of 2.66 deaths per 100 person/years (P < 0.001). After adjustment for baseline differences in patient and disease characteristics, the hazard ratio was 2.12 (CI95% = 1.86,2.58; P < 0.001). The adjusted hazard ratios for patients who survived 6 months postsurgery was 1.70 (CI95% = 1.36,2.13; P < 0.001). Mediastinitis is associated with a marked increase in both acute and long-term mortality rates.

Computer simulation of introductory neurophysiology.

A computer-assisted learning (CAL) package, NeuroLab, developed for use by first-year university students undertaking professional programs in the health area, is described and evaluated. NeuroLab is a simulation of a laboratory, in which students are able to impale neurons to measure resting membrane potentials and subsequently undertake experiments including measuring resting membrane potentials, determining threshold potentials, measuring refractory periods, and examining effects on membrane potential through altering the membrane permeability to sodium and potassium ions. Students find the package to be a worthwhile learning experience, with 81 +/- 2.2% reporting the package increased their understanding of neuron function, and 78 +/- 2.5% expressing a desire for more CAL packages. Exposure to the package resulted in significantly higher mean scores in a multiple-choice question test on measuring neuron membrane potentials compared with those who were not exposed (mean scores out of 4 of 2.42 and 2.02, respectively, P < 0.001).

Predicting vascular complications in percutaneous coronary interventions.

OBJECTIVES: Using a large, current, regional registry of percutaneous coronary interventions (PCI), we identified risk factors for postprocedure vascular complications and developed a scoring system to estimate individual patient risk. BACKGROUND: A vascular complication (access-site injury requiring treatment or bleeding requiring transfusion) is a potentially avoidable outcome of PCI. METHODS: Data were collected on 18,137 consecutive patients undergoing PCI in northern New England from January 1997 to December 1999. Multivariate regression was used to identify characteristics associated with vascular complications and to develop a scoring system to predict risk. RESULTS: The rate of vascular complication was 2.98% (541 cases). Variables associated with increased risk in the multivariate analysis included age >or=70, odds ratio (OR) 2.7, female sex (OR 2.4), body surface area <1.6 m(2) (OR 1.9), history of congestive heart failure (OR 1.4), chronic obstructive pulmonary disease (OR 1.5), renal failure (OR 1.9), lower extremity vascular disease (OR 1.4), bleeding disorder (OR 1.68), emergent priority (OR 2.3), myocardial infarction (OR 1.7), shock (1.86), >or=1 type B2 (OR 1.32) or type C (OR 1.7) lesions, 3-vessel PCI (OR 1.5), use of thienopyridines (OR 1.4) or use of glycoprotein IIb/IIIa receptor inhibitors (OR 1.9). The model performed well in tests for significance, discrimination, and calibration. The scoring system captured 75% of actual vascular complications in its highest quintiles of predicted risk. CONCLUSION: Predicting the risk of post-PCI vascular complications is feasible. This information may be useful for clinical decision-making and institutional efforts at quality improvement.

Gender-related changes in the practice and outcomes of percutaneous coronary interventions in Northern New England from 1994 to 1999.

OBJECTIVES: We sought to determine whether the changing practice of interventional cardiology has been associated with improved outcomes for women, and how these outcomes compare with those for men. BACKGROUND: Previous work from the early 1990s suggested women are at a higher risk than men for adverse outcomes after percutaneous coronary interventions (PCIs). From 1994 to 1999 data were collected on 33,666 consecutive hospital admissions for a PCI in Northern New England. Multivariate models were used to adjust for differences in case-mix across year of procedure when comparing outcomes. Direct standardization was used to calculate adjusted rates. RESULTS: From 1994 to 1999, the case-mix worsened for both women and men, although women had more co-morbidities than did men throughout the period. Stent use increased over time (>75% in 1999). Concomitantly, the need for emergency coronary artery bypass graft surgery (CABG) decreased significantly (p(trend) < or = 0.001; in 1999: 0.06% for women, 0.05% for men). Although the emergency CABG rates were higher for women at the beginning of the study, by the end, they were comparable (adjusted odds ratio 1.34, 95% confidence interval 0.76 to 2.38, p = 0.315). The myocardial infarction (MI) rates decreased over time for both women (by 29.7%, p(trend) = 0.378) and men (by 37.6%, p(trend) = 0.009) and did not differ by gender. The mortality rates did not decrease significantly over time and were not significantly different between the genders (mean 1.21% for women, 1.06% for men; p = 0.096). CONCLUSIONS: Concurrent with the changing practice of PCI, and despite treating sicker patients, there have been important improvements in post-PCI CABG and MI rates for women, as well as for men. Unlike in earlier years, there are no longer significant differences in outcomes by gender.

Benzocaine-Induced Methemoglobinemia Complicating Transesophageal Echocardiography: A Case Report.

Methemoglobinemia is a rare but potentially serious complication occurring after the administration of the anesthetic agent benzocaine. We describe the findings and subsequent treatment of a patient who developed this complication after the use of benzocaine during the course of transesophageal echocardiography.