Topological data analysis identified prognostically-distinct phenotypes in MitraClip patients

Background

Topological data analysis (TDA) is the state-of-the-art unsupervised machine learning framework that can provide insight into the dataset and visualize condensed information via the topological network graph. This robust approach was never used to assess the heterogeneous MitraClip population.

Purpose

We aim to develop a TDA model that will identify prognostically-distinct phenogroups in MitraClip patients without a priori knowledge of the population and their outcomes.

Method

Patients who underwent MitraClip (June 2014-September 2020) at Mayo Clinic sites were identified from the institutional database for baseline and follow-up data. Thirteen variables were used for TDA. The topological network graph was created using the Python Scikit-TDA Kepler-Mapper package (v. 2.0.1), and clustering was performed at the graph level with Louvain's modularity method. Kaplan-Meier survival analysis was used to assess the all-cause mortality endpoint of each cluster identified in an unsupervised manner. The dataset with cluster labels was also used to train a Light Gradient Boosted Machine model, and SHapley Additive exPlanations (SHAP) analysis was applied to determine the feature importance.

Results

A total of 389 consecutive patients were included in the final analysis and two major clusters consisting of 384 patients were identified. The mean age was 80.3±8.7 years; 256 (65.8%) were male. The mean Society of Thoracic Surgeons Mitral Valve Replacement risk score was 9.6±6.9%. Fifty-five (14.5%) patients died during the mean follow duration (185 days). Kaplan-Meier analysis showed significant survival differences among the two clusters (HR: 2.38; 95% CI: 1.39–4.06, p=0.001; Figure 1). Clusters 1 (n=195) was associated with > mild residual mitral regurgitation and worse survival performance and was characterized with worse tricuspid regurgitation severity, a higher proportion of patients with atrial fibrillation/flutter, anterior leaflet prolapse, and mitral annular/leaflet calcification, as summarized in Table 1.

Conclusion

TDA can identify distinct phenotype clusters with prognostic significance in MitraClip patients based on mitral valve morphology and clinical risk factors. This simple model can facilitate clinical risk stratification for MitraClip patients regarding procedural success and survival performance.

Funding Acknowledgement

Type of funding sources: None.

Overcoming the strength–formability trade-off in high strength steels via cryogenic treatment

High strength steels are becoming more important than ever before for automotive applications to reduce the weight of automobiles and to ensure the safety of passengers. Since increased strength usually results in degraded formability, however, cold forming of high strength steels into final shapes remains a challenge to both automotive manufacturers and suppliers. Here we report novel alloy and processing design concepts that can impart high strength to cold-formable steels, which deviates from the traditional approach of improving the formability of high strength steels. Such designed steel subjected to a designed processing route shows an excellent combination of formability and strength as well as crashworthiness, which is crucial for the safety of passengers in the automobiles. The alloy and processing design concepts used in the present study are based on the utilization of thermally induced austenite to martensite transformation, which imparts high strength to cold-formable austenite by cryogenic treatment.

Left ventricular diastolic dysfunction, including an impaired myocardial relaxation pattern, predicts long-term cardiovascular and non-cardiovascular mortality in the community

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Prior studies have demonstrated abnormalities of diastolic function are independent predictors of heart failure and all-cause mortality. The optimal way to classify diastolic function has continued to evolve over time, particularly in those with preserved left ventricular ejection fraction. A notable change in the 2016 American Society of Echocardiography (ASE)/European Association of Cardiovascular Imaging (EACVI) guidelines is that individuals with impaired myocardial relaxation and normal filling pressure can be classified as normal diastolic function.

Purpose

To determine whether the association of diastolic dysfunction with increased risk of all-cause mortality is driven by cardiovascular or non-cardiovascular death. Second, to evaluate if the presence of an impaired myocardial relaxation inflow pattern without other diastolic abnormalities conveys a marker of increased risk.

Methods

This study utilized the Olmsted County Heart Function Study (OCHFS), a well characterized prospective adult community cohort with comprehensive echocardiography between 2001 and 2004 and long-term follow-up. Only individuals with measurable diastolic function were included (n = 1,104). Those with reduced left ventricular ejection fraction, more than moderate valve disease, or a clinical diagnosis of heart failure (n = 52); or indeterminate diastolic function (n = 47) were excluded. Diastolic function was assessed by the current Mayo Clinic diagnostic algorithm (Figure).

Results

A total of 695 individuals were classified as normal, 265 with impaired myocardial relaxation or grade 1 diastolic dysfunction, and 45 with grade 2-3 diastolic dysfunction. Those with diastolic dysfunction were older and had more comorbidities including diabetes, hypertension and coronary disease (Table). There were 264 deaths in the median follow up period of 15.2 years (IQR 14.4 – 18.0), including 173 non-cardiovascular and 81 cardiovascular deaths. Both cardiovascular and non-cardiovascular mortality were associated with the presence and grade of diastolic dysfunction (Table 1). Individuals classified as normal by 2016 ASE/EACVI criteria, but grade 1 by the Mayo algorithm had an increased risk of all-cause mortality after univariate analysis (HR 4.35, 95% CI (3.35, 5.65), p < 0.0001) compared to normal subjects and remained associated after adjustment for age (HR 1.55, 95% CI (1.15, 2.09), p < 0.0001. Subjects with a grade 1 pattern had a higher rate of cardiovascular mortality (ꭕ2 70.1, p < 0.0001).

Conclusions

Individuals with diastolic dysfunction, including those with an impaired relaxation mitral inflow, were at increased risk of mortality, particularly cardiovascular mortality. This study highlights the importance of separating grade 1 diastolic dysfunction from normal in the assessment of diastolic function as it represents a clinically significant risk marker of myocardial disease. Abstract Figure.  Abstract Figure.

Early assessment of health impact of the population-based tobacco control interventions in Vietnam

Background

Through the period from 2013 until now, Vietnam has achieved progress in tobacco control following the implementation of MPOWER in 2008 and the enactment of the comprehensive Law on Prevention and Control of Tobacco Harms in 2012. This study aimed to assess the cost-effectiveness of 6 population-based interventions including health promotion & education program; smoke-free models; cessation program; graphic health warning on cigarette package; bans on advertising/ promotion/ sponsoring; raising tobacco tax.

Methods

An Excel-based Markov model was adopted based on the previous studies of HV Minh et al 2018 and Ngalesoni et al 2017. We estimated the potential health gain on Vietnamese population by using the empirical data on tobacco epidemic in Vietnam together with the reviewed intervention effects from the literature. Due to the rapid decline of risk of cardiovascular disease after the smoking behavior changed, the short-run heath impacts were mainly estimated based on the change of smoking-related health burden of cardiovascular diseases.

Results

All six population-based interventions on tobacco control that have implemented were considered to be highly cost-effective ranged from 1,405 VND - 135,560 VND per DALYs averted compared to the WHO recommended threshold at 1 GDP per capita. Raising tobacco tax was projected to the most cost-effective intervention due to its significant health gains and potential to work on in the long run. Besides, smoke-free model, as the best intervention on individual behavior change, should be continue invested together with campaigns on raising awareness.

Conclusions

The study results shown the potential health impact in tobacco control in Vietnam after 10 years' implementation of MPOWER. Also, the findings provided a strong message that more attention should be paid to developing the national tobacco control strategy in the next phase to make the best use of available resources.

Key messages

Adequate attention should be equally paid for both political interventions and individual behavior – aimed interventions (communication, cessation…) in the fight against tobacco harms. Aside from raising tobacco tax, further investigations and investments on cessation services as well as smoking bans in public places are needed in Vietnam to achieve the best compliance on MPOWER.

1680 Left ventricular filling pressure assessment with exercise stress echocardiography in patients with non-valvular atrial fibrillation

Background

Noninvasive parameters of LV filling pressure (E/e’) and pulmonary pressures (RVSP) by Doppler echocardiography correlate with functional capacity and outcome in sinus rhythm (SR). Their role in AF is less clear. Elevated left ventricular filling pressures (E/e’) and pulmonary artery systolic pressures (PASP) by Doppler stress echocardiography correlate with impaired functional capacity in patients in sinus rhythm (SR). However, there is limited data in atrial fibrillation (AF).

Purpose

The aim of this study was to delineate the characteristics of patients with AF referred for exercise stress echocardiography and determine the prevalence and significance of E/e’ and PASP elevations in AF.

Methods

Subjects were patients referred for exercise treadmill stress echocardiography (n= 14,937) and underwent regional wall motion assessment, Doppler assessment of mitral inflow (E) and early tissue relaxation (e’) velocities and PASP at rest and immediately following maximum symptom limited exercise. Exclusion criteria included significant valvular heart disease (moderate or greater stenosis and/or regurgitation of any cardiac valve or previous valve repair or replacement) (1%), congenital heart disease (<1%) or refusal to participate in research (<1%).

Results

Patients with AF (n = 310, 2%) were older (71 ± 10 vs 59 ± 13 years, p < 0.001). While resting blood pressure was similar, resting heart rates were higher in AF (80 ± 17 bpm vs 73 ± 13 bpm, p < 0.0001). AF patients achieved lower workloads (6.4 ± 2.4 METS vs 9 ± 2.4 METS, p < 0.001) with lower peak double products (22336 ± 6677 vs 25148 ± 5438, p < 0.001). Rates of resting (27% vs 10%, p < 0.0001) and exercise-induced (37% vs 20%, p < 0.0001) regional wall motion abnormalities were higher in AF. Mean E/e’ was higher in AF at rest (12 ± 5 vs 9 ± 3, p < 0.001) and with exercise (12 ± 5 vs 10 ± 4, p < 0.001), with a higher percentage of patients in AF having E/e’ ≥15 at rest (20% vs 6% in SR, p= <0.001) and with exercise in (23% vs 8%, p < 0.001). PASP was higher in AF at rest (33 ± 8 mm Hg vs 28 ± 6 mm Hg, p < 0.001) and with exercise (48 ± 12 vs 42 ± 11, p < 0.001) compared to SR. E/e’ correlated with exercise capacity in AF and in SR, with an E/e’ cutoff of 11.7 that was best predictive of impaired functional capacity (< 5 METS in women and < 7 METS in men).

Conclusions

Abnormalities of E/e’ and PASP are more prevalent in patients with AF and correlate with impaired functional capacity. In patients with AF, a medial E/e’ ratio of ≥ 12 immediately following exercise is best associated with impaired functional capacity.

P1851Long-term outcomes of transcatheter versus surgical aortic valve replacement in low risk, elderly patients with severe aortic stenosis

Background

Although surgical aortic valve replacement (SAVR) is recommended for symptomatic severe aortic stenosis (AS) patients at low surgical risk, there is a growing need for an expansion of transcatheter aortic valve replacement (TAVR) as an alternative to SAVR for elderly AS patients at low operative risk.

Purpose

We tried to compare the long-term clinical outcomes of TAVR versus SAVR in elderly AS patients (≥80 years old) at low surgical risk.

Methods

We consecutively enrolled 261 elderly patients (131 men; 83±3 years of age) with symptomatic severe AS and EuroSCORE II <4%, who underwent SAVR or TAVR from 2010 to 2018. Heart Team made the decision between SAVR and TAVR according to the individual patient's preference and characteristics. SAVR was performed on 93 patients (SAVR group), whereas TAVR was chosen for 168 patients (TAVR group). The primary end point was cardiac mortality including procedure-related death, and the secondary end point was all-cause death and cardiovascular event.

Results

Baseline characteristics were similar between the two groups, but the TAVR group was significantly older than the SAVR group (83±3 vs 82±2 years; p<0.01). Device was successfully implanted in all the patients and there was 1 in-hospital mortality in the TAVR group and 3 in-hospital mortalities in the SAVR group (p=0.13). During a median follow-up of 24 months (IQR, 9–45 months), there were 22 deaths (13.1%) including 8 cardiac deaths (4.8%) in the TAVR group and 16 deaths (17.2%) including 9 cardiac deaths (9.7%) in the SAVR group. The rates of the primary and secondary end points were similar between two groups in the overall cohort and the propensity score-matched cohort (table). On subgroup analysis according to the presence of coronary artery disease (CAD), the only independent variable associated with cardiac mortality, the SAVR group had a significantly higher cardiac mortality rate than the TAVR group (15±7% vs 7±6% at 5 years, p=0.048) in 185 (71%) patients without CAD, whereas there was no significant difference among those with CAD.

Harzard ratio for clinical outcomes TAVR (n=168) SAVR (n=93) Overall cohort TAVR (n=76) SAVR (n=76) PS-matched cohort HR (95% CI) p value HR (95% CI) p value Cardiac mortality 8 9 0.65 (0.25–1.71) 0.386 2 7 0.34 (0.07–1.61) 0.173 All-cause mortality 22 16 1.08 (0.56–2.08) 0.831 6 12 0.86 (0.30–2.43) 0.774 Cardiovascular event* 18 12 1.09 (0.52–2.28) 0.826 6 10 0.72 (0.26–1.98) 0.525 *Cardiovascular event was defined as the composite of cardiac mortality, hospitalization for heart failure, stroke, myocardial infarction, and reoperation.

Conclusion

In elderly AS patients at low surgical risk, TAVR was similar to SAVR with respect to long-term clinical outcomes. TAVR should be considered a treatment option for elderly patients who refuse to undergo surgery despite low risk.

Chemically linked metal-matrix nanocomposites of boron nitride nanosheets and silver as thermal interface materials

Herein, novel hybrid nanocomposite thermal interface materials (TIMs) relying on the chemical linkage of silver, boron nitride nanosheets (BNNSs), and organic ligands are reported. These TIMs were prepared using a co-electrodeposition/chemisorption approach where the electrolytic reduction of silver ions into silver nano-/micro-crystals was coupled with the conjugation of ligand-coated nanosheets onto silver crystals. Furthermore, the influence of the bond strength of silver/nanosheet links on the thermal, mechanical, and structural properties is investigated using a combination of techniques including laser flash analysis, phase-sensitive transient thermoreflectance, nanoindentation, and electron microscopy. The internal nanostructure was found to be strongly dependent on the linker chemistry. While the chemical grafting of 4-cyano-benzoyl chloride (CBC) and 2-mercapto-5-benzimidazole carboxylic acid (MBCA) on BNNSs led to the uniform distribution of functionalized-nanosheets in the silver crystal matrix, the physical binding of 4-bromo-benzoyl chloride linkers on nanosheets caused the aggregation and phase separation. The thermal conductivity was 236-258 W m^-1 K and 306-321 W m^-1 K for physically and chemically conjugated TIMs, respectively, while their hardness varied from 400-495 MPa and from 240 to 360 MPa, respectively. The corresponding ratio of thermal conductivity to hardness, which is a critical parameter controlling the performance of TIMs, was ultrahigh for the chemically conjugated TIMs: 1.3 × 10^-6 m² K^-1 s for MBCA-BNNS and 8.5 × 10^-7 m² K^-1 s for CBC-BNNS. We anticipate that these materials can satisfy some of the emerging thermal management needs arising from the improved performance and efficiency, miniaturization, and/or high throughput of electronic devices, energy storage devices, energy conversion systems, light-emitting diodes, and telecommunication components.

Correlation between Physical Features of Elementary School Children and Chest Compression Depth

Introduction

The height and body weight of 6th grade elementary school children may have influence on chest compression.

Materials & methods

In accordance with the 2005 American Heart Association guidelines and 2006 Korean Association of CardioPulmonary Resuscitation (CPR) guidelines, a 25-minute audiovisual presentation and practical demonstration of CPR were presented by the researchers and assistants. The assistants supervised and corrected the practical performance of the students who performed 5 cycles of CPR (2 minutes each) with the aid of the Laerdal Resusci® Anne SkillReporter™. The students then carried out another 5 cycles of CPR (2 minutes each) using the skill reporter; and a short report was printed.

Results

The correlation coefficient between body weight and chest compression was 0.467 (p=0.000), and the correlation coefficient between height and chest compression was 0.309 (p=0.009). The intercept between body weight and chest compression was 21.763 (p=0.000), and the slope was 0.324 (p=0.000). Student height showed no linear correlation with chest compression depth.

Conclusions

The body weight of 6th grade elementary school children showed moderate correlation with chest compression depth. A minimal body weight of 50 kg is required to attain a standard chest compression depth of 38 mm. With improved training, some students with body weight less than 50 kg may also achieve satisfactory performance of CPR.

The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain

Objectives

The objective of this study was to assess the association between whole body sagittal balance and risk of falls in elderly patients who have sought treatment for back pain. Balanced spinal sagittal alignment is known to be important for the prevention of falls. However, spinal sagittal imbalance can be markedly compensated by the lower extremities, and whole body sagittal balance including the lower extremities should be assessed to evaluate actual imbalances related to falls.

Methods

Patients over 70 years old who visited an outpatient clinic for back pain treatment and underwent a standing whole-body radiograph were enrolled. Falls were prospectively assessed for 12 months using a monthly fall diary, and patients were divided into fallers and non-fallers according to the history of falls. Radiological parameters from whole-body radiographs and clinical data were compared between the two groups.

Results

A total of 144 patients (120 female patients and 24 male patients) completed a 12-month follow-up for assessing falls. A total of 31 patients (21.5%) reported at least one fall within the 12-month follow-up. In univariate logistic regression analysis, the risk of falls was significantly increased in older patients and those with more medical comorbidities, decreased lumbar lordosis, increased sagittal vertical axis, and increased horizontal distance between the C7 plumb line and the centre of the ankle (C7A). Increased C7A was significantly associated with increased risk of falls even after multivariate adjustment.

Conclusion

Whole body sagittal balance, measured by the horizontal distance between the C7 plumb line and the centre of the ankle, was significantly associated with risk of falls among elderly patients with back pain.

Cite this article: J. Kim, J. Y. Hwang, J. K. Oh, M. S. Park, S. W. Kim, H. Chang, T-H. Kim. The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain. Bone Joint Res 2017;6:–344. DOI: 10.1302/2046-3758.65.BJR-2016-0271.R2.

Increased sagittal vertical axis is associated with less effective control of acute pain following vertebroplasty

OBJECTIVES

Although vertebroplasty is very effective for relieving acute pain from an osteoporotic vertebral compression fracture, not all patients who undergo vertebroplasty receive the same degree of benefit from the procedure. In order to identify the ideal candidate for vertebroplasty, pre-operative prognostic demographic or clinico-radiological factors need to be identified. The objective of this study was to identify the pre-operative prognostic factors related to the effect of vertebroplasty on acute pain control using a cohort of surgically and non-surgically managed patients.

PATIENTS AND METHODS

Patients with single-level acute osteoporotic vertebral compression fracture at thoracolumbar junction (T10 to L2) were followed. If the patients were not satisfied with acute pain reduction after a three-week conservative treatment, vertebroplasty was recommended. Pain assessment was carried out at the time of diagnosis, as well as three, four, six, and 12 weeks after the diagnosis. The effect of vertebroplasty, compared with conservative treatment, on back pain (visual analogue score, VAS) was analysed with the use of analysis-of-covariance models that adjusted for pre-operative VAS scores.

RESULTS

A total of 342 patients finished the 12-week follow-up, and 120 patients underwent vertebroplasty (35.1%). The effect of vertebroplasty over conservative treatment was significant regardless of age, body mass index, medical comorbidity, previous fracture, pain duration, bone mineral density, degree of vertebral body compression, and canal encroachment. However, the effect of vertebroplasty was not significant at all time points in patients with increased sagittal vertical axis.

CONCLUSIONS

For single-level acute osteoporotic vertebral compression fractures, the effect of vertebroplasty was less favourable in patients with increased sagittal vertical axis (> 5 cm) possible due to aggravation of kyphotic stress from walking imbalance.Cite this article: Y-C. Kim, D. H. Bok, H-G. Chang, S. W. Kim, M. S. Park, J. K. Oh, J. Kim, T-H. Kim. Increased sagittal vertical axis is associated with less effective control of acute pain following vertebroplasty. Bone Joint Res 2016;5:544-551. DOI: 10.1302/2046-3758.511.BJR-2016-0135.R1.

Second to fourth digit ratio: a predictor of adult testicular volume

It has been suggested that second to fourth digit ratio (digit ratio) may correlate with male reproductive system function or disorders. This hypothesis is based on finding that the Hox genes control finger development and differentiation of the genital bud during embryogenesis. Thus, we investigated the association between digit ratio and adult testicular volume. A total of 172 Korean men (aged 20-69 years) hospitalized for urological surgery were prospectively enrolled. Patients with conditions known to strongly influence testicular volume were excluded. Before determining testicular volume, the lengths of the second and fourth digits of the right hand were measured by a single investigator using a digital vernier calliper. Using orchidometry, the testes were measured by an experienced urologist who had no information about the patient's digit ratio. To identify the independent predictive factors influencing testicular volume, univariate and multivariate analyses were performed using linear regression models. Age, height, serum testosterone and free testosterone level were not correlated with testicular volume. Digit ratio, along with weight, was significantly correlated with testicular volume (right testicular volume: r = -0.185, p = 0.015; left testicular volume: r = -0.193, p = 0.011; total testicular volume: r = -0.198, p = 0.009). Multivariate analysis using linear regression models showed that only digit ratio was the independent factor to predict all (right, left and total) testicular volumes (right testicular volume: β = -0.174, p = 0.023; left testicular volume: β = -0.181, p = 0.017; total testicular volume: β = -0.185, p = 0.014). Our findings demonstrated that digit ratio is negatively associated with adult testicular volume. This means that men with a higher digit ratio may be more likely to have smaller testis compared to those with a lower digit ratio.

Ferrous Iron and Sulfur Oxidation and Ferric Iron Reduction Activities of Thiobacillus ferrooxidans Are Affected by Growth on Ferrous Iron, Sulfur, or a Sulfide Ore

Eight strains of Thiobacillus ferrooxidans (laboratory strains Tf-1 [= ATCC 13661] and Tf-2 [= ATCC 19859] and mine isolates SM-1, SM-2, SM-3, SM-4, SM-5, and SM-8) and three strains of Thiobacillus thiooxidans (laboratory strain Tt [= ATCC 8085] and mine isolates SM-6 and SM-7) were grown on ferrous iron (Fe), elemental sulfur (S), or sulfide ore (Fe, Cu, and Zn). The cells were studied for their aerobic Fe - and S-oxidizing activities (O(2) consumption) and anaerobic S-oxidizing activity with ferric iron (Fe) (Fe formation). Fe-grown T. ferrooxidans cells oxidized S aerobically at a rate of 2 to 4% of the Fe oxidation rate. The rate of anaerobic S oxidation with Fe was equal to the aerobic oxidation rate in SM-1, SM-3, SM-4, and SM-5, but was only one-half or less that in Tf-1, Tf-2, SM-2, and SM-8. Transition from growth on Fe to that on S produced cells with relatively undiminished Fe oxidation activities and increased S oxidation (both aerobic and anaerobic) activities in Tf-2, SM-4, and SM-5, whereas it produced cells with dramatically reduced Fe oxidation and anaerobic S oxidation activities in Tf-1, SM-1, SM-2, SM-3, and SM-8. Growth on ore 1 of metal-leaching Fe-grown strains and on ore 2 of all Fe-grown strains resulted in very high yields of cells with high Fe and S oxidation (both aerobic and anaerobic) activities with similar ratios of various activities. Sulfur-grown Tf-2, SM-1, SM-4, SM-6, SM-7, and SM-8 cultures leached metals from ore 3, and Tf-2 and SM-4 cells recovered showed activity ratios similar to those of other ore-grown cells. It is concluded that all the T. ferrooxidans strains studied have the ability to produce cells with Fe and S oxidation and Fe reduction activities, but their levels are influenced by growth substrates and strain differences.

Preoperative NT-proBNP and CRP predict perioperative major cardiovascular events in non-cardiac surgery

OBJECTIVE

To investigate whether simple and non-invasive measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP) and/or C-reactive protein (CRP) can predict perioperative major cardiovascular event (PMCE).

DESIGN

Prospective, single-centre, cohort study.

SETTING

A 1900-bed tertiary-care university hospital in Seoul, Korea Design and

PATIENTS

The predictive power of NT-proBNP, CRP and Revised Cardiac Risk Index (RCRI) for the risk of PMCE (myocardial infarction, pulmonary oedema or cardiovascular death) were evaluated from a prospective cohort of 2054 elective major non-cardiac surgery patients. Optimal cut-off values were derived from receiver operating characteristic curve (ROC) analysis.

MAIN OUTCOME MEASUREMENT

PMCE (myocardial infarction, pulmonary oedema or cardiovascular death) within postoperative 30 days.

RESULTS

PMCE developed in a total of 290 patients (14.1%). Each increasing quartile of NT-proBNP or CRP level was associated with a greater risk of PMCE after adjustment for traditional clinical risk factors. The relative risk (RR) of highest versus lowest quartile was 5.2 for NT-proBNP (p<0.001) and 3.7 for CRP (p<0.001). Both NT-proBNP (cut-off = 301 ng/l) and CRP (cut-off = 3.4 mg/l) predicted PMCE better than RCRI (cut-off = 2) by ROC analysis (p<0.001). Moreover, the predictive power of RCRI (adjusted RR = 1.5) could be improved significantly by addition of CRP and NT-proBNP to RCRI (adjusted RR 4.6) (p<0.001).

CONCLUSIONS

High preoperative NT-proBNP or CRP is a strong and independent predictor of perioperative major cardiovascular event in non-cardiac surgery. The predictive power of current clinical risk evaluation system would be strengthened by these biomarkers.

Arthrodesis of the knee using cannulated screws

We retrospectively evaluated eight patients who underwent arthrodesis of the knee using cannulated screws. There were six women and two men, with a mean age of 53 years. The indications for arthrodesis were failed total knee arthroplasty, septic arthritis, tuberculosis, and recurrent persistent infection. Solid union was achieved in all patients at a mean of 6.1 months. One patient required autogenous bone graft for delayed union. One suffered skin necrosis which was treated with skin grafting. The mean limb-length discrepancy was 3.1 cm. On a visual analogue scale, the mean pain score improved from 7.9 to 3.3. According to the Knee Injury and Osteoarthritis Outcome score quality of life items, the mean score improved from 38.3 pre-operatively to 76.6 at follow-up. Cannulated screws provide a high rate of union in arthrodesis of the knee with minimal complications, patient convenience, and a simple surgical technique.

Combination drug therapy using edaravone and Daio-Orengedoku-to after transient focal ischemia in rats

In this study, we investigated the effect of Daio-Orengedoku-to (DOT) on ischemic brain damage in a rat model of focal ischemia-reperfusion and attempted to identify synergistic effects for the combination of edaravone and DOT against ischemic insult. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 2 h and reperfusion followed for 22 h. To determine the neuroprotective effect of DOT, it was administered orally just before reperfusion and then 2 h after reperfusion. To examine the effects of combination therapy on survival, rats were divided into groups treated with edaravone, DOT, and edaravone and DOT. Microglial activation, neutrophil infiltration and brain-derived neurotrophic factor (BDNF) expression were examined in surviving animals. Infarct volume was significantly reduced by DOT (100, 200 and 400 mg/kg; P < 0.05), and edaravone plus DOT markedly improved the survival rate after transient ischemia (P = 0.0133). Microglial activation was reduced by edaravone and DOT and their combination (P < 0.05), and neutrophil infiltration was lowered in these groups (P < 0.05). BDNF-positive cells were increased in the combination edaravone and DOT group (P < 0.05). It appears that the neuroprotective mechanisms of combined therapy involve inhibition of microglial activation, reduction of invading neutrophils and enhancement of BDNF expression.

Left ventricular diastolic functional reserve during exercise in patients with impaired myocardial relaxation at rest

BACKGROUND

Patients with similar grade diastolic dysfunction at rest may have a spectrum of alterations in diastolic function during exercise.

OBJECTIVE

To evaluate (a) whether exercise could unmask further diastolic abnormalities not evident during rest; (b) whether diastolic functional reserve during exercise is associated with exercise capacity.

METHODS

141 subjects (77 male, mean (SD) age 62 (9)) with abnormal left ventricular (LV) relaxation (mitral E/A <0.75) and/or deceleration time >240 ms, underwent graded supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. Mitral inflow and annular velocities were measured at rest and during exercise. The LV diastolic function reserve index (DFRI) was calculated.

RESULTS

Patients were classified into two groups: group 1 (n = 64), DFRI <13.5; group 2 (n = 77), DFRI >or=13.5. The ratio of E/E' to stroke volume was used as an index of ventricular elastance (Ed). No significant differences between the groups in mitral inflow and annular velocities at rest were found. Mean (SD) Ed was not significantly different at rest between the groups (0.19 (0.07) vs 0.18 (0.06), p = 0.29). Ed was significantly higher during exercise in group 1 than in group 2 (25 W, 0.21 (0.09) vs 0.14 (0.04), p<0.001; 50 W, 0.22 (0.10) vs 0.15 (0.04), p<0.001). Group 1 subjects had a shorter exercise duration (8.2 (2.7) vs 9.4 (3.7) min, p = 0.04) and lower peak oxygen consumption (17.5 (4.5) vs 20.2 (5.4) ml/kg/min, p = 0.005).

CONCLUSIONS

Despite similar mitral flow and annular velocities at rest, different responses to exercise were seen in patients with abnormal LV relaxation at rest. Lower LV diastolic functional reserve was associated with higher ventricular elastance during exercise, and reduced exercise capacity.

'Hypersynchronisation' by tissue velocity imaging in patients with cardiac amyloidosis

OBJECTIVE

It is unknown if some patients with cardiac amyloidosis (CA) have mechanical dyssynchrony, as has been demonstrated in patients with ischaemic and dilated cardiomyopathies. The aim of this study was to assess mechanical dyssynchrony in patients with CA using tissue velocity imaging (TVI) and to define its usefulness for risk stratification.

DESIGN AND PATIENTS

We included 121 patients with primary amyloidosis and 37 age-matched and sex-matched controls. Patients were divided into two groups: 60 with advanced-CA and 61 with no-advanced-CA, according to left ventricular (LV) wall thickness and diastolic dysfunction. Dyssynchrony assessment included: (1) atrioventricular dyssynchrony (dys), (2) interventricular dys, (3) intraventricular dys assessed longitudinally, using the standard deviation of time to systolic peak velocity (Ts-SD) of the 12 basal and mid level LV segments, and (4) intraventricular dys assessed radially, using the difference in radial Ts between mid anteroseptal and mid posterior segments.

OUTCOME

Primary end-point was all-cause death. During a median follow-up of 13 months there were 35 events among patients.

RESULTS

Contrary to the hypothesis, the intraventricular dys indices in advanced-CA patients were reduced compared to either the no-advanced-CA group or to controls (Ts-SD: 12.1 (9.0); 35.1 (18.6); 24.5 (14.1), respectively, p<0.001). This reduction was primarily the result of decreased ejection time (ET). Moreover, ET was the most significant predictor of survival (HR = 0.98, p<0.001).

CONCLUSIONS

The regional timing of systolic motion measured by TVI was abnormally synchronised in the patients with advanced-CA. ET reduction plays a prominent part in this process and should be considered an essential parameter for assessment of patients with cardiac amyloidosis.

Ethnic characteristics of eyelashes: a comparative analysis in Asian and Caucasian females

BACKGROUND

Despite similar biochemical composition of human hair between races, physico-morphological characteristics are not identical in different ethnic groups. Eyelashes have been investigated far less than scalp hair, and the information available is insufficient.

OBJECTIVES

To obtain basic information about eyelashes and to clarify differences between female eyelashes in Asians and Caucasians.

METHODS

Twenty Asian and 10 white Caucasian female volunteers aged between 20 and 29 years were admitted to the study. Lateral digital photographs of upper eyelashes were taken and curl-up and lift-up angles of upper eyelashes were measured from lateral views. Images of upper eyelashes were also taken using the phototrichogram technique and total numbers, lengths and thicknesses of upper eyelashes were obtained (a total of 4661 eyelashes; 2946 for Asian, 1715 for Caucasian). The central portion of the eyelashes or whole eyelashes were clipped and images were taken immediately and 7 days later to obtain the growth rate and anagen ratio of upper eyelashes. Numbers and thickness of eyelash cuticular layers were obtained by electron microscopy.

RESULTS

Compared with Caucasians, Asian eyelashes revealed lower lift-up and curl-up angles, fewer numbers and a thicker transverse diameter. However, no statistical difference was observed in length or growth rate. Duration of anagen was estimated at about 2 months. The eyelash anagen ratio obtained from five Asians was 17.8 +/- 3.3%. By electron microscopy, the number of cuticular layers in transverse section was greater in Asian (8.0 +/- 1.2) than Caucasian females (6.5 +/- 1.1), but no statistical difference was found in single cuticle layer thickness between the two groups. Moreover, eyelash characteristics were not influenced by eye makeup in either race.

CONCLUSIONS

Our results on eyelash morphology and growth characteristics demonstrated significant ethnic differences in Asian and Caucasian females that could provide basic information for future investigations.

Calibration of CE-QUAL-W2 for a monomictic reservoir in a monsoon climate area

The impact of inflow mixing on reservoir stratification is significant for reservoirs situated in a monsoon climate area. It cause difficulty in the calibration of a two-dimensional hydrodynamic and water quality model, CE-QUAL-W2 that was recently adopted for a real-time turbidity monitoring and modelling system (RTMMS) for a reservoir in Korea. This paper presents a systematic calibration and verification processe of the model for the reservoir. A sensitivity analysis showed that wind sheltering, Chezy, and sediment heat exchange coefficients are most sensitive to stratification structure. Inflow temperature was very sensitive during a year of normal precipitation, but it is not significant during a year of drought. Residual analysis revealed that the model has shortcomings in the simulation of water temperature near the metalimnetic zone without calibration. After calibration, however, the absolute mean errors between observed and simulated values were placed within 0.116-1.190 degrees C. Its performance was maintained under heavy flood events during the verification stage, which implies that the model is ready to use for the simulation of turbidity plume in the RTMMS under various hydrologic conditions. The suggested model calibration strategy and relevant results may be adopted for other reservoirs located in a monsoon climate area.

Personal experiences and algorithm of endoscopically assisted subperiosteal face lift in orientals for 5 years

Orientals are anatomically distinct from Caucasians and are characterized by a thick dermis, a Mongoloid slant of the palpebral fissure, a relatively prominent zygoma and mandible angle, and a relatively flat nose. Given these characteristics, it was believed that the subperiosteal face lift was not suitable for Orientals. However, at our institution, endoscopically assisted subperiosteal face lifts were performed from May of 1994 to October of 1998 on 236 patients; variable pitfalls, as well as satisfying results, were reported. Patient ages ranged from 29 to 66 years (mean age, 55.2 years), and follow-up ranged from 6 to 44 months (mean follow-up, 23 months). All forehead and brow lifts were performed using an endoscopic guide, and routine corrugator resections and procerus myotomies were performed. Three slanted cortical tunnels were made at the corresponding locations on the outer table of the calvarium, and 1-0 nylon or screw suspension and fixation were performed after a 1-cm to 2-cm lift. Midface lifts were performed through lower blepharoplasty incisions and vertical temporal incisions instead of through conventional preauricular and postauricular incisions. Dissections were made subperiosteally and over the deep layers of deep temporal fascia. Malar fat pads were suspended with 1-0 nylon and affixed to deep temporal fascia. Most patients have been satisfied with their postoperative results, but unfavorable results and complications have been reported. Complications were classified as early or late complications or unfavorable results on the basis of the 3-week postoperative evaluation. There were 28 early complications (11.9 percent), consisting of ecchymosis with edema (persisting for up to 4 weeks), paresthesia, lagophthalmos, accentuated Mongoloid slant, small dimpling on the scalp, and scalp fold formation on the fixation site. There were 13 late complications/unfavorable results (5.5 percent), consisting of insufficient lift, exaggeration of sunken upper eyelids, intermittent headaches, itching sensations, and paresthesia on the scalp. The unfavorable results occurred in the patients who had previously undergone blepharoplasty and in those who had a history of foreign body injections into the face, fatty and thick faces, sunken upper eyelids, Mongoloid slants, and asymmetric facial expressions. Through understanding the anatomic characteristics of the Oriental face (i.e., thick dermis, Mongoloid slant of palpebral fissure, prominent zygoma and mandible angle, and flat nose), satisfying results were achieved by appropriate application of the modified procedures.

Annulus paradoxus: transmitral flow velocity to mitral annular velocity ratio is inversely proportional to pulmonary capillary wedge pressure in patients with constrictive pericarditis

BACKGROUND

The early diastolic velocity of the mitral annulus (E') is reduced in patients with diastolic dysfunction and increased filling pressures. Because transmitral inflow early velocity (E) increases progressively with higher filling pressures, E/E' has been shown to have a strong positive relationship with pulmonary capillary wedge pressure (PCWP) and left ventricular end-diastolic pressure. However, previous studies have primarily involved patients without a pericardial abnormality. In constrictive pericarditis (CP), E' is not reduced, despite increased filling pressures. This study evaluated the relationship between E/E' and PCWP in patients with CP.

METHODS AND RESULTS

We studied 10 patients (8 men; mean age, 64+/-7 years) with surgically confirmed CP. Doppler echocardiography was performed to measure early and late diastolic transmitral flow velocities. Tissue Doppler echocardiography was performed to measure E'. PCWP was measured with right heart catheterization. All patients were in sinus rhythm. Mean E and E' were 91+/-15 cm/s and 11+/-4 cm/s, respectively. Mean PCWP was 25+/-6 mm Hg. E' was positively correlated with PCWP (r=0.69, P=0.027). There was a significant inverse correlation between E/E' and PCWP (r=-0.74, P=0.014). Despite high left ventricular filling pressures, E/E' (mean, 9+/-4) was <15 in all but 1 patient.

CONCLUSIONS

Paradoxical to the positive correlation between E/E' and PCWP in patients with myocardial disease, an inverse relationship was found in patients with CP.

Contrast dobutamine stress echocardiography: clinical practice assessment in 300 consecutive patients

In this study we compared non-contrast imaging with contrast imaging of the left ventricle during dobutamine stress echocardiography (DSE). Wall segment visualization, image quality, and confidence of interpretation were determined with and without the use of intravenous Optison, a second-generation echocardiographic contrast agent, in 300 consecutive patients undergoing rest and peak DSE. At rest and at peak stress, the percentage of wall segments visualized, image quality, and confidence of interpretation were better with contrast compared with non-contrast imaging. No significant decrease was seen in wall segment visualization, image quality, or confidence of interpretation from rest to peak stress in images obtained with contrast, unlike the images obtained without contrast from rest to peak stress. The use of the intravenous echocardiographic contrast agent Optison during DSE significantly improved wall segment visualization and image quality at rest and at peak stress, resulting in improved confidence of interpretation.

Prognostic value of exercise echocardiography in patients after coronary artery bypass surgery

To assess the prognostic value of exercise echocardiography in patients with prior coronary artery bypass surgery, follow-up was obtained in 718 patients (591 men [82%] and 127 women [18%], aged 67 +/- 9 years) who underwent clinically indicated exercise echocardiography 5.7 +/- 4.7 years after coronary bypass surgery. Resting wall motion abnormalities were present in 479 patients (67%). New or worsening wall motion abnormalities developed with exercise in 366 patients (51%). During a median follow-up of 2.9 years, cardiac events included cardiac death in 36 patients and nonfatal myocardial infarction in 40 patients. The addition of the exercise echocardiographic variables, abnormal left ventricular end-systolic volume response and exercise ejection fraction to the clinical, resting echocardiographic and exercise electrocardiographic model provided incremental information in predicting cardiac events (chi-square 37 to chi-square 42, p = 0.02) and cardiac death (chi-square 38 to chi-square 43, p <0.02). Exercise echocardiography provides prognostic information in patients after coronary artery bypass surgery, incremental to clinical, rest echocardiographic, and exercise electrocardiographic variables.

Mechanism of oxidation of inorganic sulfur compounds by thiosulfate-grown Thiobacillus thiooxidans

Thiobacillus thiooxidans was grown at pH 5 on thiosulfate as an energy source, and the mechanism of oxidation of inorganic sulfur compounds was studied by the effect of inhibitors, stoichiometries of oxygen consumption and sulfur, sulfite, or tetrathionate accumulation, and cytochrome reduction by substrates. Both intact cells and cell-free extracts were used in the study. The results are consistent with the pathway with sulfur and sulfite as the key intermediates. Thiosulfate was oxidized after cleavage to sulfur and sulfite as intermediates at pH 5, the optimal growth pH on thiosulfate, but after initial condensation to tetrathionate at pH 2.3 where the organism failed to grow. N-Ethylmaleimide (NEM) inhibited sulfur oxidation directly and the oxidation of thiosulfate or tetrathionate indirectly. It did not inhibit the sulfite oxidation by cells, but inhibited any reduction of cell cytochromes by sulfur, thiosulfate, tetrathionate, and sulfite. NEM probably binds sulfhydryl groups, which are possibly essential in supplying electrons to initiate sulfur oxidation. 2-Heptyl-4-hydroxy-quinoline N-oxide (HQNO) inhibited the oxidation of sulfite directly and that of sulfur, thiosulfate, and tetrathionate indirectly. Uncouplers, carbonyl cyanide-m-chlorophenylhydrazone (CCCP) and 2,4-dinitrophenol (DNP), inhibited sulfite oxidation by cells, but not the oxidation by extracts, while HQNO inhibited both. It is proposed that HQNO inhibits the oxidation of sulfite at the cytochrome b site both in cells and extracts, but uncouplers inhibit the oxidation in cells only by collapsing the energized state of cells, delta muH+, required either for electron transfer from cytochrome c to b or for sulfite binding.

Evaluation of diastolic function: old and new methods

Understanding and evaluation of diastolic function have changed with the development of new diagnosis methods. Careful attention to various aspects of diastolic function can provide valuable clinical information regarding the diagnosis for patient's heart failure, estimation of left ventricular filling pressures, optimal management strategy, and prognosis. With the advent of noninvasive hemodynamic methods, the evaluation of diastolic function can be performed routinely as a part of assessment of cardiac function.

Diagnostic value of echocardiography in cardiac tamponade

Cardiac tamponade is a life-threatening condition. Accurate diagnosis and prompt intervention are necessary to prevent adverse outcomes. Clinical features of tamponade such as pulsus paradoxus, tachycardia, elevated jugular venous pressure, and hypotension are important clues to the diagnosis, but are non-specific. Echocardiography allows rapid confirmation of the presence or absence of an effusion, and enables assessment of its hemodynamic impact. Decisions regarding treatment must take into account the clinical presentation and echocardiographic findings. Echocardiographically-guided pericardiocentesis with catheter drainage is the primary treatment strategy of choice for most large or hemodynamically significant effusions. In contemporary clinical practice, echocardiography is the gold standard for diagnosis of tamponade and is essential for directing treatment.

The role of intraoperative transesophageal echocardiography in patients undergoing cardiac mass removal

To evaluate the role of intraoperative transesophageal echocardiography (IOTEE) during surgical removal of cardiac masses, we studied 75 consecutive patients (34 men, aged 56 +/- 16 years, range 17 to 82 years) who underwent surgery primarily for cardiac mass removal with the adjunct of IOTEE for the years 1993 through 1998. The IOTEE provided new information before bypass in 6 patients (8%), altering the planned surgical procedure in all. A newly discovered patent foramen ovale was closed in 2 patients, a second myxoma discovered in one patient, a mitral valve repaired in one patient, inferior vena caval cannulation site clarified in one patient, and in one patient the mass was no longer present and the surgery canceled. In 10 patients (13%), new post-bypass information was found, which prompted return to bypass for valve repair in 3 patients, altered nonsurgical management in 3 patients, and did not necessitate specific measures in 4 patients. Thus, in 75 patients coming to surgery for mass removal, IOTEE affected intraoperative management in 12 (16%).

Clinical utility of Doppler echocardiography and tissue Doppler imaging in the estimation of left ventricular filling pressures: A comparative simultaneous Doppler-catheterization study

BACKGROUND

Noninvasive assessment of diastolic filling by Doppler echocardiography provides important information about left ventricular (LV) status in selected subsets of patients. This study was designed to assess whether mitral annular velocities as assessed by tissue Doppler imaging are associated with invasive measures of diastolic LV performance and whether additional information is gained over traditional Doppler variables.

METHODS AND RESULTS

One hundred consecutive patients referred for cardiac catheterization underwent simultaneous Doppler interrogation. Invasive measurements of LV pressures were obtained with micromanometer-tipped catheters, and the mean LV diastolic pressure (M-LVDP) was used as a surrogate for mean left atrial pressure. Doppler signals from the mitral inflow, pulmonary venous inflow, and TDI of the mitral annulus were obtained. Isolated parameters of transmitral flow correlated with M-LVDP only when ejection fraction <50%. The ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/E') showed a better correlation with M-LVDP than did other Doppler variables for all levels of systolic function. E/E' <8 accurately predicted normal M-LVDP, and E/E' >15 identified increased M-LVDP. Wide variability was present in those with E/E' of 8 to 15. A subset of those patients with E/E' 8 to 15 could be further defined by use of other Doppler data.

CONCLUSIONS

The combination of tissue Doppler imaging of the mitral annulus and mitral inflow velocity curves provides better estimates of LV filling pressures than other methods (pulmonary vein, preload reduction). However, accurate prediction of filling pressures for an individual patient requires a stepwise approach incorporating all available data.

Assessment of cardiac risk before nonvascular surgery: dobutamine stress echocardiography in 530 patients

OBJECTIVE

This study evaluated the incremental value of dobutamine stress echocardiography (DSE) for assessment of cardiac risk before nonvascular surgery.

BACKGROUND

Limited information exists regarding the preoperative assessment of cardiac risk in patients with known or suspected coronary artery disease who are to undergo nonvascular surgery.

METHODS

All patients (303 men, 227 women) who underwent DSE before nonvascular surgery and did not sustain an intervening event (coronary revascularization or cardiac event) were studied. Clinical, electrocardiographic and rest and stress echocardiographic variables were evaluated to identify predictors of postoperative cardiac events.

RESULTS

Events occurred in 6% of patients: 1 cardiac death and 31 nonfatal myocardial infarctions. All of these patients had inducible ischemia on DSE (sensitivity 100%, specificity 63%). Multivariate predictors of postoperative events in patients with ischemia were history of congestive heart failure (p = 0.006; odds ratio = 4.66; confidence interval 1.55 to 14.02) and ischemic threshold less than 60% of age-predicted maximal heart rate (p = 0.0001; odds ratio 7.002; confidence interval 2.79 to 17.61). Clinical variables of Eagle's index identified 21% of patients as low, 68% as intermediate and 11% as high risk preoperatively; the postoperative event rates were 3%, 6%, and 14%, respectively. Dobutamine stress echocardiography identified 60% of patients as low (no ischemia), 32% as intermediate (ischemic threshold 60% or more) and 8% as high risk (ischemic threshold < 60%); postoperative event rates were 0%, 9% and 43%, respectively.

CONCLUSIONS

In this population of patients with known or suspected coronary artery disease evaluated before nonvascular surgery, DSE had incremental value over clinical, electrocardiographic and rest echocardiographic variables for identifying patients at low, intermediate and high risk for postoperative cardiac events. Ischemia occurring at less than 60% of age-predicted maximal heart rate identified patients at highest risk.

Severe aortic stenosis with low transvalvular gradient and severe left ventricular dysfunction:result of aortic valve replacement in 52 patients

BACKGROUND

The outcome of aortic valve replacement in patients with severe aortic stenosis, low transvalvular gradient, and severe left ventricular dysfunction is not well known.

METHODS AND RESULTS

Between 1985 and 1995, 52 patients with left ventricular ejection fraction (EF) < or =35% and aortic stenosis with transvalvular mean gradient <30 mm Hg underwent aortic valve replacement. The mean (+/-SD) preoperative characteristics included EF, 26+/-8%; aortic valve mean gradient, 23+/-4 mm Hg; aortic valve area, 0.7+/-0.2 cm(2); and cardiac output, 3.7+/-1.2 L/min. Simultaneous coronary artery bypass graft surgery was performed in 32 patients (62%). Perioperative (30-day) mortality was 21% (11 of 52 patients). Ten additional patients died during follow-up. Advanced age (P=0.048) and small aortic prosthesis size (P=0.03) were significant predictors of hospital mortality by univariate analysis. By multivariate analysis, the only predictor of surgical mortality was smaller prosthesis size. The only predictor of postoperative survival was improvement in postoperative functional class (P=0.04). Postoperative functional improvement occurred in most patients. Postoperative EF was assessed in 93% of survivors; 74% demonstrated improvement. Positive change in EF was related to smaller preoperative aortic valve area and female sex.

CONCLUSIONS

Despite severe left ventricular dysfunction, low transvalvular mean gradient, and increased operative mortality, aortic valve replacement was associated with improved functional status. Postoperative survival was related to younger patient age and larger aortic prosthesis size, and medium-term survival was related to improved postoperative functional class.

Impact of atropine injection on heart rate response during treadmill exercise echocardiography: a double-blind randomized pilot study

We evaluated the effect of atropine on the heart rate (HR) response during treadmill exercise echocardiography. A potential limitation of treadmill exercise echocardiography is the requirement for postexercise imaging. Rapid recovery of HR and wall motion abnormalities may decrease test sensitivity. A double-blind randomized study was performed at a tertiary care center. Fifty-two patients (age, 63 +/- 9 years) with known or suspected coronary artery disease were injected with either 0.5 mg of atropine or saline before treadmill exercise echocardiography. HR response during and after exercise was recorded. Atropine resulted in a greater increase in HR before exercise (increase of 15 +/- 9 vs 5 +/- 7 beats per minute, P < 0.0001) and a higher HR rate during the first 5 minutes of exercise (P < 0.05). In recovery, there was an exponential decrease in HR in both atropine and control groups. However, at the end of image acquisition (66 +/- 15 seconds), the HR was higher in the atropine group (128 +/- 21 vs 115 +/- 19 beats per minute, P = 0.02) and remained higher throughout the 10-minute recovery period (P = 0.0015). Dry mouth was more common after atropine injection (P = 0.005); other side effects were similar. The extent and resolution of myocardial ischemia were comparable in both groups. Atropine injection before treadmill exercise echocardiography results in a higher HR during the acquisition of echocardiographic images; whether atropine could affect the diagnostic accuracy of tread mill exercise echocardiography requires further study.

Calcific constrictive pericarditis: is it still with us?

BACKGROUND

The presence of pericardial calcification on a plain radiograph strongly suggests constrictive pericarditis in patients with heart failure. However, calcific constrictive pericarditis is considered rare in the United States since tuberculosis incidence has decreased, and doubt has therefore been raised about the importance of this radiologic finding in modern cardiovascular practice.

OBJECTIVE

To determine the clinical and prognostic significance of pericardial calcification on radiography in patients with constrictive pericarditis.

DESIGN

Retrospective cohort study.

SETTING

Tertiary referral center.

PATIENTS

A consecutive series of 135 patients (mean age +/- SD, 56 +/- 16 years) who from 1985 through 1995 had constrictive pericarditis confirmed surgically (n = 133) or by autopsy (n = 2). Patients were divided into two groups: those with pericardial calcification on chest radiography (group I) and those without (group II).

MEASUREMENTS

Clinical and diagnostic findings were compared in both groups, and outcome was compared in 132 patients who had pericardiectomy.

RESULTS

Pericardial calcification was seen in 36 patients (27%). The cause of constrictive pericardial disease was indeterminate in 67% of patients in group I and in 21% of patients in group II (P < 0.001). Patients in group I had had symptoms for a longer period and were more likely to have pericardial knock, larger atrial size, and atrial arrhythmia. Significantly more perioperative deaths were seen in group I, but incidence of late survival and incidence of noncalcific disease were similar in both groups.

CONCLUSIONS

Pericardial calcification is a common finding in patients with constrictive pericarditis. It is often associated with idiopathic disease and other markers of disease chronicity and is an independent predictor of increased perioperative mortality rates.