- Bohemia, New York, United States
Simcha Pollack
St. John's University, CIS/DS, Faculty Member
Research Interests: Biology and Science News
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BACKGROUND The implications of early postnatal body weight changes (Δbw) in the morbidities related to body fluid metabolism in sick preterm infants in not well investigated. The extremely low birth weight infants (ELBW, birth weight... more
BACKGROUND The implications of early postnatal body weight changes (Δbw) in the morbidities related to body fluid metabolism in sick preterm infants in not well investigated. The extremely low birth weight infants (ELBW, birth weight <1000 g) have the highest incidence of such morbidities among all neonates. AIM To determine the relationships between Δbw and neonatal morbidities associated with body fluid metabolism in the ELBW infants. METHODS In an observational study, the associations between daily weight changes from birth weight (DΔ bw) and oxygen dependence on postnatal day 28 (BPD28), patent ductus arteriosus (PDA), intraventricular-periventricular hemorrhage (IVH), antenatal steroid (ANS) and gestational age (GA) were evaluated. Maximum weight loss (MΔ bw) was correlated with GA, BPD28 and BPD36 (oxygen dependence on postmenstrual 36 weeks). Pearson's correlation co-efficient and multivariate logistic regressions were performed for analysis. RESULTS DΔ bw correlated inversely with GA on days 1-8 of life (p < 0.01 for all, 0.06 for DOL 2). DΔ bw was associated with a lower risk of BPD28 on days 6 (OR 0.87, 95% CI 0.76-1), 10 (OR 0.86, 95% CI 0.76-0.98) and 11 (OR 0.87, 95% CI 0.77-0.99); with PDA on days 8-11 (OR ranging between 0.89 to 0.92 for the 4 days, 95% CI 0.83 to 0.99) and with IVH on day 5 (OR 0.93, 95% CI 0.86-1) after controlling for GA. DΔ bw was not identified as risk factor for the tested morbidities. ANS decreased DΔ bw on days 4 (OR 0.88, 95% CI 0.78-1) and 10 (OR 0.9, 95% CI 0.84-1). MΔbw correlated directly with BPD28 (r = 0.3, p = 0.004), which declined after controlling for GA (r = 0.2, p = 0.2). CONCLUSIONS DΔ bw is protective for PDA, BPD28 and IVH, independent of gestational age, whereas, the effects of MΔ bw on BPD are governed by maturation in ELBW infants. ANS decreases DΔbw, which correlates inversely with GA during the first week of life.
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Background: Basal septal hypertrophy (BSH) is found in 1.5 %-18% of the general population associated with hypertension. Its significance in severe aortic stenosis (AS) is uncertain. Hypothesis: In AS, BSH may adversely affects LV... more
Background: Basal septal hypertrophy (BSH) is found in 1.5 %-18% of the general population associated with hypertension. Its significance in severe aortic stenosis (AS) is uncertain. Hypothesis: In AS, BSH may adversely affects LV diastolic function and increases transvalvular gradients after valve replacement (AVR). Methods: Between 2011-2014, 6012 pts with AS of some degree underwent echocardiography. Severe AS was present in 255 with a septal buldge and normal EF, of whom 30 had BSH (AS+/BSH+). 106 were AS+/BSH-. Controls included 119 AS-/BSH+ pts. 38 with AS+/BSH+ with any EF underwent AVR. BSH was defined as BS diastolic diameter ≥ 15 mm and BS >2 mm thicker than mid septum in PSLAX view in multiple images. Inter and intraobserver reliability were calculated (ICC, n = 20). One-way ANCOVA, Fisher’s exact test and multivariate logistic regression controlled for age, sex and BSA were used as appropriate. Results: ICC = 0.99 for BS and 0.80 for mid septum. AS+/BSH+ pts were older than AS+/BSH-, more were females and their diastolic function was worse despite similar transvalvular gradients, AVAi, LV mass index (table), and similar medical histories. After controlling for prosthetic valve type and size and stroke volumes, BSH did not affect post AVR transvalvular gradients. In adjusted logistic regression models, BSH was associated with E/A (OR = 2.6, CL s:1.32 and 5.29, p =0.006, AUC = 0.85) and showed a trend toward association with LA area index ( OR = 1.14, CLs,1.14 and 0.99, p = 0.06, AUC = 0.77). Conclusions: 1. Using rigorous criteria,
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Introduction: To reduce QT measurement error, a new method was tested in which high-gain, high-speed, simultaneous 12-lead electrocardiographic (ECG) recordings were obtained during a single cardiac cycle. To increase its predictive... more
Introduction: To reduce QT measurement error, a new method was tested in which high-gain, high-speed, simultaneous 12-lead electrocardiographic (ECG) recordings were obtained during a single cardiac cycle. To increase its predictive power, the utility of combining QTD with the QRS duration for predicting susceptibility to ventricular tachyarrhythmia (VT) was analyzed. Methods and results: A total of 113 patients referred for electrophysiological study underwent baseline simultaneous 12-lead ECG followed by electrophysiological study to determine VT inducibility. Twenty-six patients had inducible VT while 87 patients did not. QT intervals and the width of QRS complex were measured from a single cardiac cycle with high-gain (8 times normal) and high-speed (100 mm/second) 12-lead ECG recordings. This method resulted in 100% QT interval identification throughout all 12 leads for every patient. Receiver-operator characteristic curves (ROC) and the areas under the ROC curves (AUC) were used to quantitatively analyze the performance of four ECG variables (QTD3, QTD12, QTD12 + QRS and QTD3 + QRS). All four ECG variables were significantly increased in the patients with inducible VT as compared to those without inducible VT. The QTD3 algorithm was less useful than QTD12 in predicting inducible VT; however, the addition of QRS duration to all QTD algorithms enhanced VT detection. Conclusion: 1) QRS duration has an incremental benefit in the detection of VT when combined with QTD; 2) QTD12 + QRS duration provided the highest predictive power among the four tested algorithms; 3) high-gain, high-speed 12-lead ECG recordings reduced QT measurement error.
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Studies in the literature that attempt to relate neuroleptic plasma levels to the development of tardive dyskinesia (TD) report inconsistent findings. As part of an open, long-term study, 60 schizophrenic and schizoaffective patients were... more
Studies in the literature that attempt to relate neuroleptic plasma levels to the development of tardive dyskinesia (TD) report inconsistent findings. As part of an open, long-term study, 60 schizophrenic and schizoaffective patients were started gradually on a b.i.d. schedule of the atypical antipsychotic drug clozapine. Blood samples were drawn weekly for 6 weeks and analyzed for a variety of constituents including clozapine plasma levels. Patients with higher levels of TD were found to have significantly higher levels of plasma clozapine and a higher ratio of plasma/dose than those with lower levels of TD. Our data suggests that schizophrenics with TD may have different pharmacokinetics, drug metabolism, and elimination processes than those without TD. Higher typical plasma neuroleptic levels may increase susceptibility to TD development. A second hypothesis implies that it is not the higher mean plasma level of a neuroleptic that is associated with TD but the greater fluctuations of plasma levels over time (i.e., a higher variance). This hypothesis is discussed in the context of our data.
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Two depressed patients with long QT syndrome who experienced torsade de pointes ventricular tachycardia when treated with psychotropic drugs are discussed. These cases emphasize the significance of electrocardiographic evaluation of... more
Two depressed patients with long QT syndrome who experienced torsade de pointes ventricular tachycardia when treated with psychotropic drugs are discussed. These cases emphasize the significance of electrocardiographic evaluation of depressed patients, particularly in patients who show evidence of a long QT interval.
Research Interests: Psychology, Medicine, Electrocardiography, Humans, Female, and 13 morePubmed, Long QT syndrome, Depressive Disorder, Aged, Middle Aged, Cardiac Arrhythmias, Clinical Psychiatry, Psychotropic Drugs, Ventricular Tachycardia, QT interval, Tachycardia, Psychology and Cognitive Sciences, and Medical and Health Sciences
A number of studies have reported reduced rehospitalization for patients on clozapine. This article adds to that literature by mining the clozapine database at Hillside Hospital. The sample consisted of 81 schizophrenia patients who... more
A number of studies have reported reduced rehospitalization for patients on clozapine. This article adds to that literature by mining the clozapine database at Hillside Hospital. The sample consisted of 81 schizophrenia patients who entered Hillside on a typical neuroleptic and then had their medication changed to clozapine. We ascertained the number of inpatient hospitalizations before starting clozapine and compared this with the number of hospitalizations after starting clozapine. We also followed an age- and gender-matched comparison group of other schizophrenia patients who entered Hillside at approximately the same time. Results indicate that the mean number of rehospitalizations while on a typical neuroleptic was 2.03 (1.93)/year, whereas it was only .56 (.97/year after the commencement of clozapine treatment; t(80) = 5.78, p < .001. A 95% confidence interval for the superiority of clozapine over standard neuroleptic treatment as measured in rehospitalizations/year is (1.0, 2.0). The decrease in hospitalization rate of .4 (1.6)/year (pre-index date minus post-index date) for the comparison group was also statistically significant [t(80) = 2.3, p < .03]; the 95% confidence interval for this decrease over time is (.1, .8). The pre-post change was much greater for the clozapine patients than comparison patients. A 2 x 2 repeated measures analysis of variance (ANOVA) contrasting the comparison group to the clozapine patients both before and after the index date indicates a significant time by group interaction (F(1.80) = 22.35, p < .001), thus documenting the greater relative decrease in rehospitalization rate in the clozapine group.
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The importance of persistent negative symptoms in schizophrenia as a limiting factor in psychosocial and vocational rehabilitation has been increasingly emphasized. As a result, treatment trials and new drug development programs are... more
The importance of persistent negative symptoms in schizophrenia as a limiting factor in psychosocial and vocational rehabilitation has been increasingly emphasized. As a result, treatment trials and new drug development programs are focusing more attention on negative symptoms. Unfortunately, there is enormous phenomenological overlap between negative symptoms and neuroleptic-induced parkinsonism. We report data from a cohort of 56 clozapine-treated patients demonstrating significant correlations between measures of akinesia and anergia. Despite an average drug washout of over 2 weeks, the persistence of drug-induced parkinsonism can confound the assessment of therapeutic drug effects on negative symptoms.
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A cohort of 243 HIV-seropositive Ethiopian immigrants has been studied clinically and immunologically since their arrival in Israel in May 1991. The prevalence of HIV infection in this Ethiopian community is 1.74%, with a male to female... more
A cohort of 243 HIV-seropositive Ethiopian immigrants has been studied clinically and immunologically since their arrival in Israel in May 1991. The prevalence of HIV infection in this Ethiopian community is 1.74%, with a male to female ratio of 1.3:1. The median age is 30 years; women are somewhat younger (median 29) than men (median 33). The prevalence of HIV infection among Ethiopian immigrants is similar to the estimated rate found in the general population in Ethiopia (1.85%). Blood median counts of CD4 positive and CD8 positive T cells on first determination were 391 and 878 x 10(6)/l respectively. The number of HIV carriers with CD4 levels below 300 and 200 x 10(6)/l in a subcohort of 172 individuals was 52 (30.2%) and 26 (15.1%), respectively. The vast majority (> 90%) of the cohort are still clinically asymptomatic. This, and the fact that immigrants tested prior to 1991 were all HIV negative, attest to the recent introduction of HIV infection into this population. In spite of the recency of HIV infection, CD4 counts were relatively low in a high proportion of infected individuals.
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Research Interests: Psychology, Medicine, Humans, Female, Pubmed, and 5 moreMale, Dyskinesia, Adult, Tardive Dyskinesia, and Clozapine
Clinical and biological measures were examined for their relationship to clinical response to clozapine. Associations were found between therapeutic response and the following variables: male gender, paranoid schizophrenia subtype... more
Clinical and biological measures were examined for their relationship to clinical response to clozapine. Associations were found between therapeutic response and the following variables: male gender, paranoid schizophrenia subtype diagnosis, older age at onset of illness, shorter duration of illness, higher levels of pretreatment acute EPS, low pretreatment CSF HVA/5-HIAA, greater decrease in prolactin (PRL) and increase in growth hormone (GH) response to apomorphine stimulation pretreatment and greater inhibition by clozapine treatment of PRL and GH response to apomorphine, and plasma clozapine levels above 350 ng/mL. These results are consistent with other investigators' findings and have practical and heuristic implications for the use of clozapine and understanding its mechanism of action.
Research Interests: Psychology, Schizophrenia, Medicine, Probability, Growth Hormone, and 15 moreHumans, Prolactin, Internal Medicine, Female, Pubmed, Male, Adult, Clinical Psychiatry, Age Factors, Clozapine, Apomorphine, Age of Onset, Antipsychotic agents, Psychology and Cognitive Sciences, and Medical and Health Sciences
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ABSTRACT
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As general hospitals search for ways to cut costs without sacrificing efficiency, particular attention has been focused on factors that may prolong hospital stay. The results of prior studies that have reported an association between... more
As general hospitals search for ways to cut costs without sacrificing efficiency, particular attention has been focused on factors that may prolong hospital stay. The results of prior studies that have reported an association between psychological and psychiatric comorbidity and longer hospital stays have been subject to different interpretations because of methodological design flaws. The current paper reports on a study of psychological comorbidity and length of stay that has been designed to avoid the methodological problems of earlier investigations. The study was performed at a 429-bed tertiary-care, university-affiliated, voluntary, teaching hospital. During hospital days 3 to 5, patients were tested as available with the Mini-Mental State examination, the Zung Depression Inventory, and the SCL-90 and were rated for physical impairment with the Karnofsky Performance Status Scale. Statistical analyses were performed for correlations between length of stay and test scores, rating scales, and demographic and discharge data from the chart. Of 424 patients approached, 321 (76%) agreed to participate and 278 (65.6%) completed the test battery. Depression, anxiety, and organicity, measured by psychological tests, were significantly correlated with longer hospital stay. These correlations remained significant after the authors controlled for degree of physical impairment, emergency versus elective admission, and medical versus surgical service, which were themselves correlated with longer hospital stay. This study confirms a significant correlation between psychological comorbidity and length of stay after correcting for the methodological pitfalls found in earlier studies. The clinical, research, economic, and policy implications of these findings are discussed.
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Objectives: To substitute the stroke volume index (SVi) with flow rate (FR) in the hemodynamic classification of severe aortic stenosis (AS) with preserved ejection fraction (EF), in order to evaluate its prognostic value. Methods: A... more
Objectives: To substitute the stroke volume index (SVi) with flow rate (FR) in the hemodynamic classification of severe aortic stenosis (AS) with preserved ejection fraction (EF), in order to evaluate its prognostic value. Methods: A total of 529 patients (78.8 ± 9.8 years old, 44.1% males) with isolated severe AS (aortic valve area, AVA &lt; 1 cm2), EF ≥50%, in sinus rhythm, who underwent transthoracic echocardiography, were stratified by FR (≥/&lt; 200 mL/s) and mean pressure gradient (MG) (≥/&lt; 40 mm Hg): FRnormal/MGhigh, FRlow/MGhigh, FRnormal/MGlow, and FRlow/MGlow. Results: Aortic valve replacement was more frequently performed in the FRnormal/MGhigh than in the FRlow/MGlow group (69.3 vs. 47%, respectively, p &lt; 0.0001), yielding a similar survival benefit across all four groups. Over a median follow-up of 51 ± 29 months, there were 249 deaths. In highly adjusted models, the FRlow/MGlow group had a higher all-cause mortality (HR = 1.7, 95% CI: 1.1–2.6, p = 0.02) than patients with FRnormal/MGhigh. FR had a stronger association with AVA than SVi (r = 0.51 vs. 0.41, respectively, p = 0.0002), and a similar predictive value for death (AUC = 0.57 and 0.58, respectively, p = 0.88). Conclusions: The FRlow/MGlow subset of AS is associated with the worst prognosis, and FR is not superior to SVi in the hemodynamic classification of severe AS.
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Research Interests: Cardiology, Biomarkers, Calcium, Treatment Outcome, Medicine, and 12 moreHumans, Internal Medicine, Female, Male, Aged, Middle Aged, C reactive protein, Public health systems and services research, Atorvastatin, Coronary Artery Disease, coronary artery calcium, and Cardiovascular medicine and haematology
Spouse and adult child caregivers of older adults with major depressive disorder (N = 150) were asked what was most difficult and most rewarding about providing assistance to their relatives. Content analysis of their responses revealed... more
Spouse and adult child caregivers of older adults with major depressive disorder (N = 150) were asked what was most difficult and most rewarding about providing assistance to their relatives. Content analysis of their responses revealed seven areas of difficulty and three areas of reward. Difficulties and rewards were selectively associated with the caregiver&#39;s identity, patient clinical characteristics, and caregiver emotional adjustment. Caregiver perceived family difficulties and emotional difficulties were associated with the course of patient psychiatric illness over 1 year.
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Research Interests: Gastroenterology, Incidence Geometry, Adolescent, Medicine, Humans, and 15 moreInternal Medicine, Placebo, Female, Male, Placebos, Vitamin, Aged, Middle Aged, Questionnaires, Adult, Randomized Controlled Trial, Respiratory Tract Infections, Upper Respiratory Tract Infection, Medical and Health Sciences, and Cholecalciferol
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Research Interests: Biology and Science News
... H. George Nurnberg, MD, Ozzie Siegel, PhD, Robert Prince, PhD, Philip E. Levine, MD, Marjorie Raskin, MD, and Simcha Pollack, PhD ... to the di agnosis were raised in terms of a number of sociological issues (Caplan, 1987; Kass et... more
... H. George Nurnberg, MD, Ozzie Siegel, PhD, Robert Prince, PhD, Philip E. Levine, MD, Marjorie Raskin, MD, and Simcha Pollack, PhD ... to the di agnosis were raised in terms of a number of sociological issues (Caplan, 1987; Kass et al., 1989; Rosewater, 1987: Walker, 1987): (1 ...
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Introduction: The changes and the prognostic implications of left atrial (LA) volumes (LAV), LA function, and vascular load in patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS) are less... more
Introduction: The changes and the prognostic implications of left atrial (LA) volumes (LAV), LA function, and vascular load in patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS) are less known. Methods: We enrolled 150 symptomatic patients (mean age 82 ± 8 years, 58% female, and pre-TAVI aortic valve area 0.40 ± 0.19 cm/m2) with severe AS who underwent 2D transthoracic echocardiography and 2D speckle tracking echocardiography at average 21 ± 35 days before and 171 ± 217 days after TAVI. The end point was a composite of new onset of atrial fibrillation, hospitalization for heart failure and all-cause death (major adverse cardiac events [MACE]). Results: After TAVI, indexed maximal LA volume and minimum volume of the LA decreased by 2.1 ± 10 mL/m2 and 1.6 ± 7 mL/m2 (p = 0.032 and p = 0.011, respectively), LA function index increased by 6.8 ± 11 units (p &lt; 0.001), and LA stiffness decreased by 0.38 ± 2.0 (p = 0.05). No other changes in the LA phasic volumes, emptying fractions, and vascular load were noted. Post-TAVI, both left atrial and ventricular global peak longitudinal strain improved by about 6% (p = 0.01 and 0.02, respectively). MACE was reached by 37 (25%) patients after a median follow-up period of 172 days (interquartile range, 20–727). In multivariable models, MACE was associated with both pre- and post-TAVI LA global peak longitudinal strain (hazard ratio [HR] 0.75, CI 0.59–0.97; and HR 0.77, CI 0.60–1.00, per 5 percentage point units, respectively), pre-TAVI LV global endocardial longitudinal strain (HR 1.37, CI 1.02–1.83 per 5 percentage point units), and with most of the LA phasic volumes. Conclusion: Within 6 months after TAVI, there is reverse LA remodeling and an improvement in LA reservoir function. Pre- and post-TAVI indices of LA function and volume remain independently associated with MACE. Larger studies enrolling a greater diversity of patients may provide sufficient evidence for the utilization of these imaging biomarkers in clinical practice.
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Research Interests: Adolescent, Medicine, Comorbidity, Humans, Psychiatric Comorbidity, and 15 moreFollow-up studies, American, Depressive Disorder, Mental Disorders, Length of Stay, Aged, Psychological Tests, Adult, Hostility, Cognition disorders, Severity of Illness Index, Psychiatric Status Rating Scales, Psychology and Cognitive Sciences, Medical and Health Sciences, and Patient readmission
Research Interests: Gastroenterology, Inflammation, Pharmacokinetics, Medicine, Birth Weight, and 15 moreHumans, Placebo, Female, Male, Placebos, Pediatric, Lung, Newborn Infant, Oxygen, Bronchopulmonary Dysplasia, Gestational Age, Lung Injury, Cohort Studies, Paediatrics and reproductive medicine, and Infant Premature
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Background Left atrial (LA) reservoir function as measured by LA global longitudinal strain (LAGS) is an independent predictor of left ventricular (LV) performance and has prognostic value. Purpose To evaluate by speckle tracking... more
Background Left atrial (LA) reservoir function as measured by LA global longitudinal strain (LAGS) is an independent predictor of left ventricular (LV) performance and has prognostic value. Purpose To evaluate by speckle tracking echocardiography (STE), LAGS and other myocardial deformation indices changes after transarterial valve implantation (TAVI) for severe isolated aortic stenosis (AS) in relation to the outcome measures. Methods Of 995 pts who underwent TAVI at our Institution between 2017–18, 120 (age = 82.8±7.7 years, 74% female, AVAi = 0.37±0.09 cm2/m2, LVEF = 61.6±11.3%, no &amp;gt; than 2+ mitral or aortic regurgitation, all in NSR) underwent 2-D echocardiography and STE, pre (21±34 days) and post (16±27 days) TAVI. LAGS was measured at QRS onset, and LV global longitudinal strain (LVGS) and RV free wall strain were recorded. The velocity index = peak vel LVOT/AV. Phillips IE 33 scanners (frame rates 60–80 Hz) were used and one observer analyzed data on QLAB software. The median follow-up was 208 days (range 20–763). The outcome variable was a composite of death, atrial fibrillation and hospitalization for heart failure (MACE). Univariate and multivariable logistic regression were used to determine independent predictors of LA, LV and RV free wall global strain changes (covariates; age, sex, BSA, LVEF, systolic blood pressure, LA volume index) and, separately, for predictors of MACE (covariates; age, sex, AVA index, LVEF and E/e&#39;). Intra- and interclass correlation coefficients (ICC) were calculated. Results The intra- and inter-observer ICC was 0.70–0.90 and 0.90–0.95, respectively. In the absence of LA volume change, LAGS improved post TAVI in 54% of pts. Overall, mean change was 2.2±11.6% (95% CI; 0.05, 4.3) and it was significantly associated in multivariable analysis with RV free wall strain (OR=2.7, 95% CI; 1.2, 6), velocity index (OR=0.4, 95% CI; 0.2, 1), LVEF (OR= 0.3, 95% CI; 0.2, 0.8) and LVGS (OR=3.8, 95% CI; 1.4, 10), yielding together an AUC of 0.90. LVGS improved in 64% of pts by −2.8±7.5%, (95% CI: −4.2, −1.5) and the velocity index independently predicted the LVGS change (OR = 0.6; 95% CI: 0.4, 0.9). The other deformation indices did not significantly change. At follow-up, there were 6 hospitalizations for heart failure, 5 atrial fibrillation events and 6 deaths. At multivariable logistic regression analysis, post TAVI LAGS was the only variable independently predicting MACE (OR (in units of 1%) = 0.90, 95% CI; 0.82, 0.98), estimating that a 1% increase in post-LAGS decreases the likelihood of MACE by 10%. Conclusions 1. There was no relationship between LA systolic volume and LAGS change after TAVI. 2. Within a month after the procedure, LAGS improves in less than half of pts and is directly associated with both ventricles systolic function and AS severity. 3. At a median of 9 months after TAVI, post procedural LAGS is an independent predictor of MACE and could be used in the risk stratification of such pts.
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Research Interests: Risk assessment, Medicine, Electrocardiography, Humans, Female, and 13 moreMale, Heart, Aged, Nuclear Cardiology, Public health systems and services research, Risk Assessment, Myocardial Perfusion Imaging, Exercise Test, Myocardial Ischemia, Patient care management, Patient selection, Cardiovascular medicine and haematology, and Electric stimulation
Endoscopic ultrasound guided fine needle aspiration biopsy versus mediastinoscopy in the staging of non-small cell lung cancer: a cost effective analysis
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Coronary computed tomographic angiography (CCTA) may provide both anatomic and CT fractional flow reserve data (CTFFR). The objective is to use Bayesian analysis to develop a model wherein the probability of significant coronary artery... more
Coronary computed tomographic angiography (CCTA) may provide both anatomic and CT fractional flow reserve data (CTFFR). The objective is to use Bayesian analysis to develop a model wherein the probability of significant coronary artery disease (CAD) by CTFFR can be determined given the prior probability (P) of the combined clinical and CCTA result. 172 patients referred for CCTA and subsequently underwent coronary angiography were automatically referred to CTFFR analysis. A clinical P risk score (CRS) was calculated per patient. CCTA exams were scored using CAD-RADS classification. CTFFR results were generated. CAD was defined as ≥ 3 RAD class for CCTA and ≤ .80 by CTFFR. P was calculated using CCTA and CTFFR accuracy from a prior clinical trial: post-test P for the CCTA result used the CRS as the prior risk, and CTFFR P used the post-test CRS + CCTA P as the prior risk (tri-variable). Patients were classified for each model into low (< 5%), intermediate, (5–70%) and high (> 70%) risk groups. There were 100 patients (58%), who had significant CAD at angiography. 58 patients had discordant CCTA/CTFFR results. The inclusion of the CRS and CRS + CCTA in the prior progressively reduced the intermediate risk cohort from 83 to 41% (p < 0.0001). Correct classifications (low-risk, negative angiogram plus high-risk, positive angiogram) increased by model: CRS = 12%, CRS + CCTA = 25%, CRS + CTFFR = 33%, CRS + CCTA + CTFFR = 44% (p < 0.001). Incorrect classifications were reduced to 15%. The tri-variable model performed better than either CCTA or CTFFR alone for all patients and for the sub-group with discordant imaging results. Discrepant CCTA and CTFFR results are present in one third of patients. The use of both the CRS and CCTA as the prior risk synergistically maximized the accuracy of the accuracy of the CTFFR technique.
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59 patients with suspected infective endocarditis on a natural valve were studied by M-Mode echocardiography to determine the specificity of the ultrasonic technique in detecting valvular vegetations. All echocardiograms were read... more
59 patients with suspected infective endocarditis on a natural valve were studied by M-Mode echocardiography to determine the specificity of the ultrasonic technique in detecting valvular vegetations. All echocardiograms were read independently by two observers who were unaware of the final diagnosis. Among 40 patients who later proved not to have infective endocarditis, two (5%) were diagnosed by echocardiography as having either possible or probably vegetation by at least one observer. Both patients with a false positive diagnosis of vegetation had pre-existing valvular pathology, the presence of which greatly complicated the interpretation of the echocardiogram. Inter-observer disagreement occurred in 5 of the 59 studies (8.5%). The results of this study suggest that caution should be exerted in the echocardiographic diagnosis of vegetation in patients with pre-existing valvular pathology.