Guideline-directed medical therapy implementation during hospitalization for cardiogenic shock.

AIMS: Despite significant morbidity and mortality, recent advances in cardiogenic shock (CS) management have been associated with increased survival. However, little is known regarding the management of patients who survive CS with heart failure (HF) with reduced left ventricular ejection fraction (LVEF, HFrEF), and the utilization of guideline-directed medical therapy (GDMT) in these patients has not been well described. To fill this gap, we investigated the use of GDMT during an admission for CS and short-term outcomes using the Inova single-centre shock registry. METHODS: We investigated the implementation of GDMT for patients who survived an admission for CS with HFrEF using data from our single-centre shock registry from January 2017 to December 2019. Baseline characteristics, discharge clinical status, data on GDMT utilization and 30 day, 6 month and 12 month patient outcomes were collected by retrospective chart review. RESULTS: Among 520 patients hospitalized for CS during the study period, 185 (35.6%) had HFrEF upon survival to discharge. The median age was 64 years [interquartile range (IQR) 56, 70], 72% (n = 133) were male, 22% (n = 40) were Black and 7% (n = 12) were Hispanic. Forty-one per cent of patients (n = 76) presented with shock related to acute myocardial infarction (AMI), while 59% (n = 109) had HF-related CS (HF-CS). The median length of hospital stay was 12 days (IQR 7, 18). At discharge, the proportions of patients on beta-blockers, angiotensin-converting enzyme inhibitors (ACEis)/angiotensin receptor blockers (ARBs)/angiotensin receptor/neprilysin inhibitors (ARNIs) and mineralocorticoid receptor antagonists (MRAs) were 78% (n = 144), 58% (n = 107) and 55% (n = 101), respectively. Utilization of three-drug GDMT was 33.0% (n = 61). Ten per cent of CS survivors with HFrEF (n = 19) were not prescribed any component of GDMT at discharge. Multivariable logistic regression adjusted for baseline GDMT use revealed that patients with lower LVEF and those who transferred to our centre from an outside hospital were more likely to experience GDMT addition (P < 0.05). Patients prescribed at least one additional class of GDMT during admission had higher odds of 6 month and 1 year survival (P < 0.01): On average, 6 month survival odds were 7.1 times greater [confidence interval (CI) 1.9, 28.5] and 1 year survival odds were 6.0 times greater than those who did not have at least one GDMT added (CI 1.9, 20.5). CONCLUSIONS: Most patients who survived CS admission with HFrEF in this single-centre CS registry were not prescribed all classes or goal doses of GDMT at hospital discharge. These findings highlight an urgent need to augment multidisciplinary efforts to enhance the post-discharge medical management and outcomes of patients who survive CS with HFrEF.

Members' Feedback After a Spiritual Group Psychotherapy for Inpatient, Residential, and Intensive Treatment (SPIRIT).

Six hundred and fifty-four inpatients who participated in a spiritual group therapy intervention provided qualitative feedback regarding what helped them and what could be improved. Patients revealed that enjoying a sense of connection with other people and a sense of openness in the groups and simply talking about spirituality with other people was helpful to them. Many group members requested that groups go on for a longer amount of time than 12 sessions, to have longer sessions, and to have more frequent meetings. In addition, members described improvements that could be made to the group, including members' being better screened, leaders preventing individual members from dominating discussions or from being quiet or leaving the group early, and members' wanting more structure as well as more open discussion. The findings highlight the importance of connection, openness, and spirituality when implementing spiritual group interventions in hospital settings. Implications for future research, training, and clinical interventions are discussed.

Danish translation and cultural adaptation of the Psoriatic arthritis UnclutteRed screening Evaluation (PURE-4) scale.

OBJECTIVES: Screening tools are needed to help to identify psoriatic arthritis in patients with psoriasis. The Psoriatic arthritis UnclutteRed screening Evaluation (PURE-4) questionnaire was developed for this purpose and has been shown to perform very well. The aim of this study was to translate and culturally adapt the PURE-4 scale into the Danish language. METHOD: The translational process followed the guidelines provided by the Mapi Research Trust, which include the following steps: forward translation, backward translation, cognitive interviews, and proofreading. Following the guidelines helps to maintain the content validity of the questionnaire and secures a translation that is both literally and culturally appropriate for the target population. RESULTS: All four items were modified throughout the translation process, involving mainly minor changes such as the addition of more colloquial words in the Danish version. The new Danish version of PURE-4 was reviewed and approved by the original developers. CONCLUSIONS: A Danish version of the PURE-4 questionnaire was produced. The translation and cultural adaptation of PURE-4 constitute the first step in the validation of the questionnaire in Danish patients with psoriasis.

Medical Management and Device-Based Therapies in Chronic Heart Failure.

Heart failure (HF) remains a major cause of morbidity and mortality worldwide. Major advancements in optimal guideline-directed medical therapy, including novel pharmacological agents, are now available for the treatment of chronic HF including HF with reduced ejection fraction and HF with preserved ejection fraction. Despite these efforts, there are several limitations of medical therapy including but not limited to: delays in implementation and/or initiation; inability to achieve target dosing; tolerability; adherence; and recurrent and chronic costs of care. A significant proportion of patients remain symptomatic with poor HF-related outcomes including rehospitalization, progression of disease, and mortality. Driven by these unmet clinical needs, there has been a significant growth of innovative device-based interventions across all HF phenotypes over the past several decades. This state-of-the-art review will summarize the current landscape of guideline-directed medical therapy for chronic HF, discuss its limitations including barriers to implementation, and review device-based therapies which have established efficacy or demonstrated promise in the management of chronic HF.

Cardiogenic Shock From Heart Failure Versus Acute Myocardial Infarction: Clinical Characteristics, Hospital Course, and 1-Year Outcomes.

BACKGROUND: Little is known about clinical characteristics, hospital course, and longitudinal outcomes of patients with cardiogenic shock (CS) related to heart failure (HF-CS) compared to acute myocardial infarction (AMI; CS related to AMI [AMI-CS]). METHODS: We examined in-hospital and 1-year outcomes of 520 (219 AMI-CS, 301 HF-CS) consecutive patients with CS (January 3, 2017-December 31, 2019) in a single-center registry. RESULTS: Mean age was 61.5±13.5 years, 71% were male, 22% were Black patients, and 63% had chronic kidney disease. The HF-CS cohort was younger (58.5 versus 65.6 years, P<0.001), had fewer cardiac arrests (15.9% versus 35.2%, P<0.001), less vasopressor utilization (61.8% versus 82.2%, P<0.001), higher pulmonary artery pulsatility index (2.14 versus 1.51, P<0.01), lower cardiac power output (0.64 versus 0.77 W, P<0.01) and higher pulmonary capillary wedge pressure (25.4 versus 22.2 mm Hg, P<0.001) than patients with AMI-CS. Patients with HF-CS received less temporary mechanical circulatory support (34.9% versus 76.3% P<0.001) and experienced lower rates of major bleeding (17.3% versus 26.0%, P=0.02) and in-hospital mortality (23.9% versus 39.3%, P<0.001). Postdischarge, 133 AMI-CS and 229 patients with HF-CS experienced similar rates of 30-day readmission (19.5% versus 24.5%, P=0.30) and major adverse cardiac and cerebrovascular events (23.3% versus 28.8%, P=0.45). Patients with HF-CS had lower 1-year mortality (n=123, 42.6%) compared to the patients with AMI-CS (n=110, 52.9%, P=0.03). Cumulative 1-year mortality was also lower in patients with HF-CS (log-rank test, P=0.04). CONCLUSIONS: Patients with HF-CS were younger, and despite lower cardiac power output and higher pulmonary capillary wedge pressure, less likely to receive vasopressors or temporary mechanical circulatory support. Although patients with HF-CS had lower in-hospital and 1-year mortality, both cohorts experienced similarly high rates of postdischarge major adverse cardiovascular and cerebrovascular events and 30-day readmission, highlighting that both cohorts warrant careful long-term follow-up. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03378739.

A single dose of dietary nitrate supplementation protects against endothelial ischemia-reperfusion injury in early postmenopausal women.

The onset of menopause and accompanying changes to ovarian hormones often precedes endothelial dysfunction in women. In particular, accelerated impairments in macrovascular and microvascular function coincide with the loss of estrogen, as does impaired endothelial responses to ischemia-reperfusion (IR) injury. In healthy, early postmenopausal women (n = 12; 3.9 ± 1.5 years since menopause) we tested the hypothesis that acute dietary nitrate (NO3-) supplementation would improve endothelial function and attenuate the magnitude of endothelial dysfunction following whole-arm IR in comparison with placebo. In this randomized, double-blind, placebo-controlled, crossover study we tested participants before and after NO3--rich (BRnitrate) and NO3--depleted (BRplacebo) beetroot juice (BR) consumption, as well as following IR injury, and 15 min after IR to assess recovery. Analyses with repeated-measures general linear models revealed a condition × time interaction for brachial artery flow-mediated dilation (FMD; P = 0.04), and no interaction effect was found for the near-infrared spectroscopy-derived reperfusion slope (P = 0.86). Follow-up analysis showed a significant decline in FMD following IR injury with BRplacebo in comparison with all other timepoints (all, P < 0.05), while this decline was not present with BRnitrate (all, P > 0.05). Our findings demonstrate that a single dose of dietary NO3- minimizes IR-induced macrovascular endothelial dysfunction in healthy, early postmenopausal women, but does not improve resting macrovascular and microvascular function. Trial registration number: NCT03644472. Novelty: In healthy, early postmenopausal women, a single dose of NO3--rich BR can protect against IR-induced endothelial dysfunction. This protection may be due to nitric oxide bioactivity during IR rather than improved endothelial function prior to the IR protocol per se.

Foley catheter vs oral misoprostol for induction of labor: individual participant data meta-analysis.

OBJECTIVE: To compare the effectiveness and safety of Foley catheter and oral misoprostol for induction of labor (IOL). METHODS: The Cochrane Review on Mechanical Methods for Induction of Labour and Ovid MEDLINE, EMBASE via Ovid, Ovid Emcare, CINAHL Plus, ClinicalTrials.gov and Scopus, from inception to April 2019, were searched for randomized controlled trials (RCTs) comparing Foley catheter to oral misoprostol for IOL in viable singleton gestations. Eligible trials for which raw data were obtained were included and individual participant data meta-analysis was performed. Primary outcomes were vaginal birth, a composite of adverse perinatal outcome (including stillbirth, neonatal death, neonatal seizures, admission to the neonatal intensive care unit, severe respiratory compromise or meconium aspiration syndrome) and a composite of adverse maternal outcome (including admission to the intensive care unit, maternal infection, severe postpartum hemorrhage, maternal death or uterine rupture). The quality of the included RCTs was assessed using the Cochrane Risk of Bias 2 tool and the certainty of evidence was evaluated using the GRADE approach. A two-stage random-effects model was used for meta-analysis according to the intention-to-treat principle and interactions between treatment and baseline characteristics were assessed. RESULTS: Of seven eligible trials, four provided individual participant data for a total of 2815 participants undergoing IOL, of whom 1399 were assigned to Foley catheter and 1416 to oral misoprostol. All four trials provided data for each of the primary outcomes in all 2815 women. Compared with those receiving oral misoprostol, Foley catheter recipients had a slightly decreased chance of vaginal birth (risk ratio (RR), 0.95 (95% CI, 0.91-0.99); I2 , 2.0%; moderate-certainty evidence). A trend towards a lower rate of composite adverse perinatal outcome was found in women undergoing IOL using a Foley catheter compared with oral misoprostol (RR, 0.71 (95% CI, 0.48-1.05); I2 , 14.9%; low-certainty evidence). Composite adverse maternal outcome did not differ between the groups (RR, 1.00 (95% CI, 0.97-1.03); I2 , 0%; moderate-certainty evidence). Meta-analyses of effect modifications did not show significant interactions between intervention and parity or gestational age for any of the primary outcomes. CONCLUSIONS: For women undergoing IOL, Foley catheter is less effective than oral misoprostol, as it was associated with fewer vaginal births. However, while we found no significant difference in maternal safety, Foley catheter induction may reduce adverse perinatal outcomes. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Diagnostic Limitations in Congenital Zika Virus Infection.

This is the first documented case of an infant with congenital Zika virus infection (ZVI) born in Ireland. A term infant was delivered with an antenatal diagnosis of severe microcephaly. First trimester bloods confirmed maternal ZVI and although the infant did not have Zika virus RNA or Zika-specific IgM in her blood or urine, she had multiple clinical features of congenital ZVI and Zika virus RNA was present in the placenta.

COVID-19 and Disruptive Modifications to Cardiac Critical Care Delivery: JACC Review Topic of the Week.

The COVID-19 pandemic has presented a major unanticipated stress on the workforce, organizational structure, systems of care, and critical resource supplies. To ensure provider safety, to maximize efficiency, and to optimize patient outcomes, health systems need to be agile. Critical care cardiologists may be uniquely positioned to treat the numerous respiratory and cardiovascular complications of the SARS-CoV-2 and support clinicians without critical care training who may be suddenly asked to care for critically ill patients. This review draws upon the experiences of colleagues from heavily impacted regions of the United States and Europe, as well as lessons learned from military mass casualty medicine. This review offers pragmatic suggestions on how to implement scalable models for critical care delivery, cultivate educational tools for team training, and embrace technologies (e.g., telemedicine) to enable effective collaboration despite social distancing imperatives.

Peritoneal metastases from extra-abdominal cancer - A population-based study.

INTRODUCTION: Peritoneal metastases (PM) are predominantly seen as a manifestation of intra-abdominal malignancy such as colorectal or ovarian cancer. However, extra-abdominal primary cancer can also metastasise to the peritoneum. Population-based data on the incidence of PM from extra-abdominal cancer is lacking. This study aims to assess the patterns and survival of patients in Ireland with PM from extra-abdominal cancers. METHODS: The National Cancer Registry of Ireland database was interrogated to identify patients diagnosed with PM from extra-abdominal malignancy during the period 1994-2012. Patient demographics and tumour characteristics were analysed. RESULTS: 5791 patients were diagnosed with PM during the study period. Of these, 543 (9%) had an extra-abdominal primary malignancy. Breast (40.8%), lung (25.6%) and melanoma (9.3%) were the most common extra-abdominal cancers to develop PM. The majority of patients with peritoneal metastases of breast origin (75%) were diagnosed at a long interval (median interval 59.5 months; range = 1-485) from the diagnosis of the primary. The median survival from diagnosis of PM was 5.8 months compared with 22.6 months from diagnosis of stage IV disease without peritoneal involvement. Survival in patients with lung cancer and melanoma who developed PM was very poor and similar to that in patients with stage IV disease not involving the peritoneum. CONCLUSION: This is the first population-based study to report the incidence of PM secondary to extra-abdominal malignancy. The most common primary cancers were melanoma, breast and lung cancer. Metastatic disease to the peritoneum was uniformly associated with a poor prognosis.

Cervical spine fracture through a cervical disc replacement.

INTRODUCTION: We report a rare case of cervical spine trauma through a cervical disc replacement and adjacent multilevel disc fusions. Cervical disc replacement (CDR) is a viable option for the surgical treatment of degenerative disc disease however long term follow up data regarding this operative technique is poor specifically relating to traumatic complications. We know of no previous reports of bilateral cervical pedicle fractures occurring adjacent to CDR and anterior cervical spine instrumentation. PRESENTATION OF CASE: A 46 year-old with a history of C6C7 CDR and C4-6 anterior cervical decompression and fusion was an unrestrained driver involved in a road traffic accident and suffered bilateral C7 pedicle fractures and a right C6C7 facet joint fracture-subluxation without neurological deficit. Reduction and fixation via a posterior approach achieved a satisfactory alignment and the patient made an uneventful recovery. DISCUSSION: A significant force coupled with cervical fixation resulted in a bilateral pedicle fracture of the cervical spine with preserved neurological function. CONCLUSION: The protective role of the CDR has not been previously demonstrated but may have played a role in this case. The authors believe the challenges encountered in the treatment of this patient provide valuable lessons in the management of complex cervical spine trauma in the setting of previous instrumentation.

Downregulation of heat shock protein B8 decreases osteogenic differentiation potential of dental pulp stem cells during in vitro proliferation.

OBJECTIVES: Tissue-derived stem cells, such as dental pulp stem cells (DPSCs), reduce differentiation capability during in vitro culture. We found that cultured DPSCs reduce expression of heat shock protein B8 (HspB8) and GIPC PDZ domain containing family member 2 (Gipc2). Our objectives were to evaluate the changes in DPSC composition during in vitro proliferation and to determine whether HspB8 and Gipc2 have function in differentiation potential of DPSCs. MATERIALS AND METHODS: Different passages of rat DPSCs were evaluated for changes in CD90+ and/or CD271+ stem cells and changes in osteogenic potential. Real-time RT-PCR and immunostaining were conducted to determine expression of HspB8 and Gipc2. Expression of the genes in DPSCs was knocked down by siRNA, followed by osteogenic induction to evaluate the function of the genes. RESULTS: About 90% of cells in the DPSC cultures were CD90+ and/or CD271+ cells without dramatic change during in vitro proliferation. The DPSCs at passages 3 to 5 (P3 to P5) possess strong osteogenic potential, but such potential was greatly reduced at later passages. Expression of HspB8 and Gipc2 was significantly reduced at P11 versus P3. Knock-down of HspB8 expression abolished osteogenic potential of the DPSCs, but knock-down of Gipc2 had no effect. CONCLUSIONS: CD90+ and CD271+ cells are the major components of DPSCs in in vitro culture. High-level expression of HspB8 was critical for maintaining differentiation potential of DPSCs.

Primary cesarean section and adverse delivery outcomes among women of very advanced maternal age.

OBJECTIVE: To assess associations between primary cesarean delivery and adverse delivery outcomes with very advanced maternal age. STUDY DESIGN: We conducted a population-based cohort study including 78,880 births to mothers 25 years and older with singleton births from 2003 to 2012 using Washington State birth certificates and hospital discharge data, excluding births to women with a prior cesarean section. The primary outcome was mode of delivery. Secondary outcomes included maternal transfusion, chorioamnionitis, severe perineal lacerations and prolonged length of stay. Outcomes of births to women of advanced maternal age (35 to 39, 40 to 44) and very advanced maternal age (45 to 49, ⩾50) were compared with referent births among women aged 25 to 34 years. General linear models with a log-link function were used to calculate unadjusted and adjusted relative risks and 95% confidence intervals (CIs). RESULT: Proportions and risks of primary cesarean section increased with age (25 to 34 years, referent: 20.0%; 35 to 39 years: 25.9%, relative risk (RR)=1.25 (95% CI=1.20 to 1.29); 40 to 44 years: 30.9%, RR=1.45 (95% CI=1.40 to 1.50); 45 to 49 years: 35.7%, RR=1.59 (95% CI=1.45 to 1.75); and ⩾50 years: 60.7%, RR=2.44 (95% CI=1.95 to 3.05); P-trend <0.001). Associations did not differ between primiparous and multiparous women. No differences were noted for measures of maternal morbidity, except there was a trend of increasing risk of prolonged length of stay among births to older women (P-trend <0.001). CONCLUSION: Primary cesarean delivery risk continues to increase above age 35 regardless of prior vaginal birth, with the highest risk among women aged 50 years and older.

Activation of proliferation and differentiation of dental follicle stem cells (DFSCs) by heat stress.

OBJECTIVES: Adult stem cells (ASCs) remain in a slowly cycling/quiescent state under normal physiological conditions, but they can be awakened from this by certain factors, such as injury signals. Previously, our group has shown that dental follicle stem cells (DFSCs) appear to proliferate more rapidly than their non-stem cell counterparts at elevated temperatures. The study described here has aimed to (i) elucidate optimal temperature in which to culture DFSCs, (ii) determine whether elevated temperatures could enhance differentiation capability of DFSCs and (iii) characterize stem cell and osteogenic marker expression of DFSCs at elevated temperatures. MATERIALS AND METHODS: DFSCs obtained from rat first molars were cultured at 37 (control), 38, 39, 40 and 41 ºC. Cell proliferation was evaluated by Alamar blue reduction assay and mean numbers of viable dissociated cells. Osteogenic differentiation was evaluated after 7 or 14 days osteogenic induction. Expression of selected marker genes was also assessed during proliferation and differentiation of the cells. RESULTS: Increased cell proliferation was seen at heat-stress temperatures of 38º, 39º and 40 ºC. DFSCs revealed maximal osteogenesis when cultured at 39 and 40 ºC. Moreover, some stem cell and osteogensis-associated markers had elevated expression in heat-stress conditions. CONCLUSIONS: Under determined heat-stress conditions, DFSCs increased their proliferation, osteogenic differentiation and expression of some marker genes. Thus, it is likely that elevated temperature could serve as a factor to activate adult stem cells.

Anticipating the species jump: surveillance for emerging viral threats.

Zoonotic disease surveillance is typically triggered after animal pathogens have already infected humans. Are there ways to identify high-risk viruses before they emerge in humans? If so, then how and where can identifications be made and by what methods? These were the fundamental questions driving a workshop to examine the future of predictive surveillance for viruses that might jump from animals to infect humans. Virologists, ecologists and computational biologists from academia, federal government and non-governmental organizations discussed opportunities as well as obstacles to the prediction of species jumps using genetic and ecological data from viruses and their hosts, vectors and reservoirs. This workshop marked an important first step towards envisioning both scientific and organizational frameworks for this future capability. Canine parvoviruses as well as seasonal H3N2 and pandemic H1N1 influenza viruses are discussed as exemplars that suggest what to look for in anticipating species jumps. To answer the question of where to look, prospects for discovering emerging viruses among wildlife, bats, rodents, arthropod vectors and occupationally exposed humans are discussed. Finally, opportunities and obstacles are identified and accompanied by suggestions for how to look for species jumps. Taken together, these findings constitute the beginnings of a conceptual framework for achieving a virus surveillance capability that could predict future species jumps.

A US-UK comparison of health in 1990-1991 Gulf War veterans.

BACKGROUND: UK and US military personnel appear to have different health profiles yet direct comparisons of health status and deployment exposures between US and UK military populations have never been performed. AIMS: To compare US and UK military personnel deployed to the 1991 Persian Gulf War (PGW) for rates of symptom reporting, medical conditions and health status [Short Form-36 general health perception (GHP) and physical functioning (PF) subscales] and self-report military exposures. METHODS: We analysed representative cross-sectional samples of military personnel from the Iowa Persian Gulf Study (n = 3626) and the UK Health Survey of Military Personnel (n = 5573) that included directly comparable measures and stratified by those who had been deployed to PGW and those who had not been deployed to PGW. RESULTS: Although UK veterans had similar mean PF scores as US veterans (mean differences in PGW: 0.86, 95% CI -0.36 to 2.07 and in non-deployed -0.61, 95% CI -1.84 to 0.62), they had worse mean GHP scores (mean differences in PGW: -5.62, 95% CI -7.44 to -3.80 and in non-deployed -3.83, 95% CI -5.40 to -2.27). UK PGW veterans were more likely to report Gulf specific exposures, and this was associated with worse GHP (UK mean difference -9.05, 95% CI -11.49 to -6.61 versus US mean difference -4.30, 95% CI -6.62 to -1.98). CONCLUSIONS: This study observed transatlantic variations in health status in military populations that may reflect cultural differences in the reporting of health.

Competitive electroporation formulation for cell therapy.

Established cell transfection via nucleofection relies on nucleofection buffers with unknown and proprietary makeup due to trade secrecy, inhibiting the possibility of using this otherwise effective method for developing cell therapy. We devised a three-step method for discovering an optimal formulation for the nucleofection of any cell line. These steps include the selection of the best nucleofection program and known buffer type, selection of the best polymer for boosting the transfection efficiency of the best buffer and the comparison with the optimal buffer from an established commercial vendor (Amaxa). Using this three-step selection system, competitive nucleofection formulations were discovered for multiple cell lines, which are equal to or surpass the efficiency of the Amaxa nucleofector solution in a variety of cells and cell lines, including primary adipose stem cells, muscle cells, tumor cells and immune cells. Through the use of scanning electron microscopy, we have revealed morphological changes, which predispose for the ability of these buffers to assist in transferring plasmid DNA into the nuclear space. Our formulation may greatly reduce the cost of electroporation study in laboratory and boosts the potential of application of electroporation-based cell therapies in clinical trials.

An ex vivo investigation of the relationship between apical root impedance and canal anatomy.

AIM: To investigate a possible relationship between apical root impedance and canal anatomy. METHODOLOGY: Twenty-three roots from human extracted teeth with different apical anatomy (classified by number of apical canal exits) were selected. After impedance measurements, the root canals were stained and the teeth cleared to confirm their division into simple (S - Vertucci type 1; n=12) and complex (C - various Vertucci canal types with multiple exits; n=11) root types. Impedance measurements were taken using a frequency response analyser at seven apico-coronal levels in each root (0.0, 0.5, 1.0, 2.0, 3.0, 4.0, 5.0 mm short of the apical terminus) at 14 frequencies ranging from 1120 to 100,000 Hz. Potential confounding factors were controlled. The impedance characteristics of individual roots were compared with 37 equivalent circuits to select best fit. The association between impedance characteristic (described by the selected equivalent circuit) and canal anatomy (S/C) was investigated using logistic regression with robust standard error to account for multiple data-sets from the same root. RESULTS: Canal anatomy had a significant (P= 0.046) effect on the equivalent circuit model. One circuit (model 10) occurred significantly more commonly in the simple canals. The odds of selecting circuit-model-10 were 2.2 times (odds ratio 2.17, 95% confidence interval 1.01-4.63) higher in canals with simple anatomy compared to those with complex anatomy. CONCLUSION: Canal anatomy had a significant effect on the equivalent circuit describing its impedance characteristics. It is theoretically possible to use impedance spectroscopy to clinically predict and image apical canal complexities.