In vivo intervertebral disc mechanical deformation following a treadmill walking "stress test" is inversely related to T1rho relaxation time.

OBJECTIVE: To assess the in vivo relationship between the mechanical response of intervertebral discs (IVDs) to dynamic activity and IVD biochemical composition assessed via T1rho relaxation imaging. DESIGN: Eighteen asymptomatic participants with no history of low back pain (LBP), injury, or surgery underwent magnetic resonance (MR) imaging of their lumbar spine prior to and immediately following a treadmill walking "stress test." Anatomic (SPACE, FLASH) MR images were obtained pre- and post-exercise and utilized to measure IVD mechanical deformation. Quantitative (T1rho) imaging was performed pre-exercise to reflect IVD composition. Pre-exercise anatomic images were also utilized to assess IVD degenerative status based on the modified Pfirrmann scale. To quantify mechanical response, 3D surface models of the L1-L2-L5-S1 IVDs were created from manual segmentations of pre- and post-exercise anatomic images and utilized to assess changes in IVD height. IVD strain (%) was defined as change in IVD height normalized to pre-activity height. Linear mixed models were used to assess the relationships between IVD mechanical deformation (strain), composition (T1rho relaxation time), and degenerative status (Pfirrmann grade). RESULTS: Increased compressive IVD strain was associated with lower T1rho relaxation times in the nucleus pulposus (NP) of the disc (ßT1rho=5.07,CI:[1.52,7.77],Rmarg2=0.52,p=0.005). Thus, an inverse relationship between IVD strain and NP T1rho relaxation time was observed. CONCLUSION: The in vivo mechanical response of the IVD to the "stress test" was sensitive to differences in NP composition. The results of this study suggest that quantification of in vivo IVD mechanical function and composition may provide insight into IVD health.

Arterial hypertension and remodelling of the right ventricle.

BACKGROUND: In the case of long-term and physiological loads (e.g. during pregnancy or regular athletics training), reversible morphological changes occur in the heart - cardiomyocytes undergo hypertrophy; however, this is not accompanied by impairment of left ventricular function or myocyte metabolism. However, in the course of various pathological processes, as time goes by, gradually permanent morphological changes occur. These changes are referred to as remodelling of the heart muscle, which, regardless of the primary cause, can lead to the development of chronic heart failure. MATERIALS AND METHODS: The study was performed on post-mortem material of 35 human hearts obtained from forensic sections and anatomopathological sections of people who died of non-cardiac causes (mainly traffic accidents, suicide attempts, strokes, acute infections); material was fixed in a 4% formalin solution. The hearts were subjected to macro- and microscopic assessment. During microscopic assessment the features of remodelling were evaluated. RESULTS AND CONCLUSIONS: In vivo and echocardiographic tests, as well as macroscopic evaluation of post-mortem material, suggest the presence of some kind of right ventricular muscle remodelling; however, classic microscopic observations, presented in this study, do not provide such unambiguous evidence. Thus, the question arises: why and how the right ventricular function is disturbed, sometimes at early stages of arterial hypertension.

Development of the interatrial wall during the ontogenesis of foetuses and children up to one year of age.

BACKGROUND: The foramen ovale, present in foetal interatrial septum, plays an important role during foetal life. During delivery, foramen ovale closes and becomes fossa ovalis, starting the pulmonary circulation. The aim of our study was to describe the growth of the interatrial wall and changes in location of the foramen ovale, and fossa ovalis during the ontogenesis in the human hearts. MATERIALS AND METHODS: The study was performed on post-mortem material obtained from 92 human hearts from 22nd week of foetal life up to 1 year of age, fixed in a 4% formalin solution. RESULTS: The interatrial wall size in the studied development period was greater in the horizontal than in the vertical dimension. During ontogenesis up to 1 year old, the anterior and inferior parts of the interatrial wall increased their shares considerably by 8% and 6%, respectively. The percentage participation of foramen ovale in the interatrial wall construction in the foetal period formed more than 50% of its size and fairly decreased reaching in infants about 39%. CONCLUSIONS: Our study demonstrated that during ontogenesis, from the foetal period to infancy, the parts of the interatrial wall increase their dimensions unevenly. The foramen ovale growth is smaller, compared to the rest of the interatrial wall development. On the basis of our data we can assume that the foramen ovale centre tends to be found in the postero-inferior quadrant of the interatrial wall (foetuses) and in postero-superior quadrant of the interatrial wall - in infants.

Metric analysis of the lumbar region of human vertebral column.

Detailed measurement of lumbar spine, despite the many years of study, still provides new information, especially due to low back pain, which is increasing and unresolved worldwide health problem. This review includes historical background and evolution of measurement methods. The paper also focused on searching optimal animal model of lumbar spine and summarizes current knowledge and essential tips. In addition, practical application of lumbar metric analysis was presented. This summary is a starting point for further consideration.

Körner's septum (petrosquamosal lamina): the anatomical variant or clinical problem?

Körner's septum (KS) or petrosquamosal lamina is a bony lamina beginning at the articular fossa, extending above the middle ear, and running inferiorly and laterally to the facial nerve canal as it proceeds to the mastoid apex. This septum marks the junction of petrous and squamous bones. The paper presents details of the anatomical structure of KS, which is most often present at the level of the head of the malleus and/or the anterior semicircular canal. Attention is paid to embryological aspects of temporal bone development that lead to the formation of KS. Two imaging techniques most frequently used to diagnose KS are described, high resolution computed tomography (HRCT) and cone-beam computed tomography. Also presented is a case report of a 6-year-old patient suffering from chronic otitis media who developed a cholesteatoma due to presence of KS, illustrated with HRCT images and intraoperative capture. The authors describe diagnostic difficulties associated with this anatomical variant in the middle ear. The article also discusses the more frequent occurrence of this clinical problem in ears operated on due to chronic inflammation, retraction pocket or tympanosclerosis in comparison to healthy ears.

Improving vasomotor symptoms; psychological symptoms; and health-related quality of life in peri- or post-menopausal women through yoga: An umbrella systematic review and meta-analysis.

OBJECTIVES: Vasomotor symptoms (VMS), commonly reported during menopausal transition, negatively affect psychological health and health-related quality of life (HRQoL). While hormone therapy is an effective treatment, its use is limited by concerns about possible harms. Thus, many women with VMS seek nonhormonal, nonpharmacologic treatment options. However, evidence to guide clinical recommendations is inconclusive. This study reviewed the effectiveness of yoga, tai chi and qigong on vasomotor, psychological symptoms, and HRQoL in peri- or post-menopausal women. DESIGN: MEDLINE, Cochrane Database of Systematic Reviews, EMBASE, CINAHL and the Allied and Complementary Medicine Database were searched. Researchers identified systematic reviews (SR) or RCTs that evaluated yoga, tai chi, or qigong for vasomotor, psychological symptoms, and health-related quality of life (HRQoL) in peri- or post-menopausal women. Data were abstracted on study design, participants, interventions and outcomes. Risk of bias (ROB) was assessed and updated meta-analyses were performed. RESULTS: We identified one high-quality SR (5 RCTs, 582 participants) and 3 new RCTs (345 participants) published after the SR evaluating yoga for vasomotor, psychological symptoms, and HRQoL; no studies evaluated tai chi or qigong. Updated meta-analyses indicate that, compared to controls, yoga reduced VMS (5 trials, standardized mean difference (SMD) -0.27, 95% CI -0.49 to -0.05) and psychological symptoms (6 trials, SDM -0.32; 95% CI -0.47 to -0.17). Effects on quality of life were reported infrequently. Key limitations are that adverse effects were rarely reported and outcome measures lacked standardization. CONCLUSIONS: Results from this meta-analysis suggest that yoga may be a useful therapy to manage bothersome vasomotor and psychological symptoms.

Use of mindfulness, meditation and relaxation to treat vasomotor symptoms.

Postmenopausal women with bothersome vasomotor symptoms (VMS) often seek alternatives to hormone-based treatment due to medication risks or personal preference. We sought to identify the effects of meditation, mindfulness, hypnosis and relaxation on VMS and health-related quality of life in perimenopausal and postmenopausal women. To do this, we conducted an umbrella review supplemented by new randomized, controlled trials (RCTs) published since the most recent good-quality systematic review for eligible interventions. We searched MEDLINE and the Cochrane Database of Systematic Reviews, PubMed, EMBASE, CINAHL and the Allied and Complementary Medicine Databases. We identified five systematic reviews and six new RCTs that met eligibility criteria. In a new meta-analysis examining four RCTs comparing paced respiration with a control group, we found that paced respiration is not associated with a statistically significant decrease in VMS frequency (standardized mean difference (SMD) 0.04, 95% confidence interval (CI) -0.73 to 0.82, I2 = 56.6%, three trials) or severity (SMD 0.06, 95% CI -0.69 to 0.80; I2 = 65.1%, three trials). There was not sufficient new information to conduct meta-analyses that examined the effect of mindfulness or hypnosis on our outcomes of interest. No effect on VMS or quality of life was found between various relaxation or mindfulness interventions.

Effect of the CT table strap on radiation exposure and image quality during cervical spine CT.

BACKGROUND AND PURPOSE: The CT table strap may impair shoulder lowering during cervical spine CT. The purpose of this investigation was to evaluate the effect of the CT table strap on radiation exposure and image quality during CT of the cervical spine. MATERIALS AND METHODS: Patients undergoing cervical spine CT were prospectively randomized to having the CT table strap placed around the torso and arms (control group) or around the torso only (intervention group). Radiation exposure, shoulder position, and image quality were evaluated. Potential confounders, including neck diameter and scan length, were also assessed. RESULTS: Fifty-eight patients were enrolled and randomized, and 51 subjects were included in the final study population. There was a 21% decrease in radiation exposure in the intervention group compared with the control group (mean dose-length product, 540 ± 152 versus 686 ± 200 mGy × cm, P = .005). Subjects in the intervention group achieved shoulder lowering of an average of >1 vertebral body lower than the control group (mean shoulder level, 7.7 ± 1.3 versus 6.5 ± 1.3, P = .001). Subjective image quality, determined by the lowest level of spinal cord visibility, was also better in the intervention group (mean cord visibility level, 6.9 ± 1.3 versus 5.9 ± 1.3, P = .006). No differences in neck diameter (P = .28) or scan length (P = .55) were observed between groups. CONCLUSIONS: The CT table strap inhibits shoulder lowering during CT of the cervical spine. Placement of the patient's arms outside the CT table strap results in decreased radiation exposure and increased image quality compared with patients whose arms are placed inside the strap.

Septomarginal trabecula and anterior papillary muscle in primate hearts: developmental issues.

The septomarginal trabecula is present in all human hearts as well as in the hearts of other primates. It usually connects the interventricular septum with the anterior papillary muscle, although there are many variations in how this is achieved. The object of the analyses was to estimate the bilateral topography of the septomarginal trabecula and the anterior papillary muscle in the context of the ontogeny and phylogeny of primates. A total of 138 hearts were examined from number of different non-human primates. The presence of the septomarginal trabecula was confirmed in 94.9% of cases, although not in the hearts of Lemur varius. Four configurations could be distinguished by defining the location of the septomarginal trabecula and its relation to the anterior papillary muscle.For the hearts of the Strepsirrhini and the majority of Platyrrhini neither structure was related, whereas in all examined representatives of Homino idea they had fused and created morphologically varying forms. On the basis of these results,a concept was developed for the sequence of changes which the topography of the septomarginal trabecula and the anterior papillary muscle undergo during ontogeny and phylogeny.

Following unenhanced MRI assessment for local recurrence after surgical resection of mesenchymal soft tissue tumors, do additional gadolinium-enhanced images change reader confidence or diagnosis?

PURPOSE: Evaluate if gadolinium enhanced MR imaging (GeMRI) improves confidence, changes the final diagnosis, or improves accuracy in the assessment of musculoskeletal (MSK) tumor residual or recurrence following surgical resection. We also assess if different experience levels change the above results. METHODS AND MATERIALS: Initially, pre-contrast images were independently reviewed by two radiologists, one with 25 years of experience (R1) and one undergoing MSK specialty training (R2). Two questions were answered: (1) Mass present? and (2) Likelihood of malignancy? Subsequently, both pre-contrast and post-contrast images were independently reviewed. The same questions were again answered plus four others including if GeMRI changed mass characterization, better defined cystic versus solid, better defined tumor extent, or improved conspicuity. Lastly, the readers answered whether GeMRI changed confidence, and changed their final diagnosis. Histologic diagnoses were available in 43 cases, with the remaining 44 cases based upon clinical and/or imaging follow-up. RESULTS: GeMRI definitely improved confidence in 8/7 cases, and slightly improved confidence in 20/29 cases and changed the final diagnosis in 11/8 cases for R1 and R2 respectively. Positive and negative predictive values statistically improved for R2 (positive predictive value 36.4% versus 50%, p=0.02; negative predictive value 75.4% versus 79.1%, p=0.04) but not for R1. Reader concordance for malignancy improved with GeMRI (κ=0.44 pre-contrast and κ=0.71 post-contrast). CONCLUSION: GeMRI improved reader confidence, improved reader concordance and modestly improved accuracy for the less experienced reader. Where possible, GeMRI should be used in the assessment of MSK tumor residual or recurrence.

Myocardial bridges in domestic pig--morphological aspects.

The morphology of myocardial bridges (MB) in the heart of the domestic pig remain an open issue. Despite numerous analyses of the subject, many controversies still exist. Opinions also differ when the influence of the MB on haemodynamic processes in the coronal vessel system is concerned. In the examined group of 150 domestic pig's hearts, the length of the detected MB varied from 1.8 to 39.7 mm while their thickness amounted to 0.8 - 4.7 mm. Both the longest and the thickest bridges were connected with the posterior interventricular branch. It was noticed that the MB muscle bands cross the long axis of the vessels located in the grooves mostly at almost a right angle. Three forms of perivascular space were educed using the criterion of the distance of the vessel from the surrounding muscularis externa.

Distribution of myocardial bridges in domestic pig.

Localisation and morphology of myocardial bridges in the heart of domestic pig remain an open issue. Since these structures significantly influence haemodynamics in the coronary arteries, their occurance may lead to numerous pathologies. In the examined group of 150 domestic pig's hearts, myocardial bridges were diagnosed in 47.3% of the material, mostly in males. In majority of cases the bridges were present above the posterior interventricular branch of the right coronary artery, less often above the anterior interventricular branch of the left coronary artery, and seldom above other blood vessels. The presence of myocardial bridges usually referred to the medial and initial segments of the arteries examined.

The effect of sodium-ion implantation on the properties of titanium.

This paper deals with the surface modification of titanium by sodium-ion implantation and with the effect of this modification on structure, corrosion resistance, bioactivity and cytocompatibility. The Na ions were implanted with doses of 1 x 10(17) and 4 x 10(17) ions/cm(2) at an energy of 25 keV. The chemical composition of the surface layers formed during the implantation was examined by secondary-ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS), and their microstructure--by transmission electron microscopy (TEM). The corrosion resistance was determined by electrochemical methods in a simulated body fluid (SBF) at a temperature of 37 degrees C, after exposure in SBF for various times. The surfaces of the samples were examined by optical microscopy, by scanning electron microscopy (SEM-EDS), and by atomic force microscopy (AFM). Biocompatibility of the modified surface was evaluated in vitro in a culture of the MG-63 cell line and human osteoblast cells. The TEM results indicate that the surface layers formed during the implantation of Na-ions are amorphous. The results of the electrochemical examinations obtained for the Na-implanted titanium samples indicate that the implantation increases corrosion resistance. Sodium-ion implantation improves bioactivity and does not reduce biocompatibility.

The initial zones of the atrioventricular node: really neglected anatomical features of potential clinical significance?

The constant evolution of medical knowledge and accompanying development of diagnostic and treatment possibilities for arrhythmias and conduction disturbances has reawakened interest in the structure and function of the conduction system of the human heart, especially in the region of the atrioventricular (AV) junction and within the junction itself. Of the large number of studies dealing with the AV junction few focus on the initial zones of the AV node. These were described for the first time by Tawara in 1906. Similarly, Anderson et al. distinguished two origins of the AV node, the left one running towards the basis of the mitral valve and the right one leading towards the tricuspid valve. The differences in length and scale could be the result of the adoption of different reference points. The study was carried out on the material of 50 human hearts, of both sexes and ranging in age from 22 to 93, which were fixed in 10% formalin and 98% ethanol solution. The tissue obtained was fixed in the 10% formalin solution and, after being sunk in the paraffin, was cut into layers of about 10 mum thick. According to the age of the hearts, every 10(th) or 6(th) section was stained by the Masson-Goldner method. The preparations were examined under a LEICA 2000 and BIOLAR 2 microscope at magnifications of 2x to 400x. Each of the 50 examined hearts contained the atrioventricular node and its initial parts. We observed that the initial zone of the AV node is created by an assembly of cells typical for a conduction system that can create three groups that are initially independent of each other and are always arranged around the AV nodal artery. In all the hearts examined we found at least two initial parts of the node: the superior and inferior. These two groups were present in 45 hearts (90%). In the last 5 cases (10%) there was also a middle group. No cases were found either with a single initial group or without any initial groups. In the sections examined the superior group appeared to be first in 27 hearts (54%), while in 23 cases (46%) the inferior group was first. The length of each group was measured from its first appearance to its first direct contact with the second part. The length of the superior part varied from 0.15 to 2.91 mm (mean 0.90 +/- 0.6 mm), the inferior from 0.11 to 2.41 mm (mean 0.88 +/- 0.6 mm) and the middle from 0.67 to 2.21 mm (mean 1.04 +/- 0.7 mm). As mentioned above, in all 50 hearts there was a direct connection between the atrial muscle and the upper origin of AV node. Furthermore, in all sections (100%) the same part of the interatrial septal muscle was connected to the compact part of the node. Additionally, in 3 cases (6%) we were able to observe direct connections between the muscle fibres running from the fasciculus limbicus inferior to the initial zone of the AV node: in 2 cases (4%) with the superior group and in 1 case (2%) with the inferior group. In 8% of the material the atrial muscle of the supra-orificial zone made direct contact with the superior initial group and the compact zone of the node and in 10% there was contact between the suborificial muscle and the inferior group and the compact part of the node. This configuration was not observed in relation to the middle and inferior groups.

The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial.

BACKGROUND: Transcranial Doppler ultrasound (TCD) and magnetic resonance angiography (MRA) can identify intracranial atherosclerosis but have not been rigorously validated against the gold standard, catheter angiography. The WASID trial (Warfarin Aspirin Symptomatic Intracranial Disease) required performance of angiography to verify the presence of intracranial stenosis, allowing for prospective evaluation of TCD and MRA. The aims of Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial were to define abnormalities on TCD/MRA to see how well they identify 50 to 99% intracranial stenosis of large proximal arteries on catheter angiography. STUDY DESIGN: SONIA standardized the performance and interpretation of TCD, MRA, and angiography. Study-wide cutpoints defining positive TCD/MRA were used. Hard copy TCD/MRA were centrally read, blind to the results of angiography. RESULTS: SONIA enrolled 407 patients at 46 sites in the United States. For prospectively tested noninvasive test cutpoints, positive predictive values (PPVs) and negative predictive values (NPVs) were TCD, PPV 36% (95% CI: 27 to 46); NPV, 86% (95% CI: 81 to 89); MRA, PPV 59% (95% CI: 54 to 65); NPV, 91% (95% CI: 89 to 93). For cutpoints modified to maximize PPV, they were TCD, PPV 50% (95% CI: 36 to 64), NPV 85% (95% CI: 81 to 88); MRA PPV 66% (95% CI: 58 to 73), NPV 87% (95% CI: 85 to 89). For each test, a characteristic performance curve showing how the predictive values vary with a changing test cutpoint was obtained. CONCLUSIONS: Both transcranial Doppler ultrasound and magnetic resonance angiography noninvasively identify 50 to 99% intracranial large vessel stenoses with substantial negative predictive value. The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis trial methods allow transcranial Doppler ultrasound and magnetic resonance angiography to reliably exclude the presence of intracranial stenosis. Abnormal findings on transcranial Doppler ultrasound or magnetic resonance angiography require a confirmatory test such as angiography to reliably identify stenosis.

Basic axes of human heart in correlation with heart mass and right ventricular wall thickness.

A comparison of the data published in anatomy textbooks and anthropological tables does not reveal any change in basic heart dimensions during the period since the beginning of the 20th century to nowadays. However, normal values of many other parameters have changed up to 30% over the same period. These changes may be caused by the acceleration phenomenon or the extension of average lifespan. The progress of laboratory medicine methodology permitted the introduction of new biochemical tests in myocardial infarct diagnosis, such as myoglobin and troponins T and I measurement, as well as better understanding of cardiac metabolism. Parameters describing the direction and intensity of metabolic changes are substrate extraction and metabolic equilibrium. The expression describing metabolic equilibrium contains heart mass value. Therefore, as studying heart mass in vivo is not possible, it may be important to study it in vitro. The study was performed on a group of 107 formalin-fixed human hearts. The organs came from adults of both sexes: 30 women and 77 men, aged 18 to 90 years. None of the hearts carried signs of macroscopic developmental abnormalities or pathologic changes.

Intravascular radiation therapy after balloon angioplasty of narrowed femoropopliteal arteries to prevent restenosis: results of the PARIS feasibility clinical trial.

PURPOSE: To conduct a feasibility study to assess the feasibility, safety, and outcome of endoluminal gamma radiation therapy after balloon angioplasty of superficial femoral artery (SFA) lesions. MATERIALS AND METHODS: Forty patients with claudication were enrolled in the study and underwent percutaneous transluminal angioplasty (PTA) of SFA lesions with a mean lesion length of 9.8 cm +/- 3.0 and a mean reference vessel diameter of 5.2 mm +/- 3.1. After successful PTA, a segmented centering balloon catheter was positioned to cover the PTA site. The patients were then transported to the radiation oncology suite and treated with a microSelectron HDR afterloader with use of an Ir-192 source with a prescribed dose of 14 Gy, 2 mm into the vessel wall. Ankle-brachial index (ABI) and Rutherford score were evaluated at 1, 6, and 12 months after the procedure and angiographic follow-up was conducted at 6 months. RESULTS: Radiation was delivered successfully to 35 of 40 patients. There were no procedural complications. Exercise and rest ABI were higher at 1 year (0.72 +/- 0.26 and 0.89 +/- 0.18, respectively) compared to baseline (0.51 +/- 0.25 and 0.67 +/- 0.17, respectively). Maximum walking time on a treadmill increased from 3.41 min +/- 2.41 to 4.43 min +/- 2.49 at 30 days and was 4.04 min +/- 2.8 at 12 months. The angiographic binary restenosis rate at 6 months was 17.2% and the clinical restenosis rate at 12 months was 13.3%. There were no angiographic or clinical adverse events related to the radiation therapy. CONCLUSIONS: Intraarterial radiation after PTA of SFA lesions with use of high-dose rate gamma radiation is feasible and safe. The angiographic and clinical improvements are sustainable at 1 year and represent a potent antirestenotic therapy for the treatment of narrowed peripheral arteries.

Myocardial bridges in the human heart: morphological aspects.

The structures made of myocardium running most often above the coronary arteries are called the muscle bridges. However there is a large number of descriptions of that phenomenon, the data are not homogenous. Some papers affirm the occurrence of the clinical implications of their existence. The studied material contained 100 adult human hearts, both sexes, 21 to 76 years of age, preserved in formalin-ethanol solution. Standard anatomical methods were used in analysis with the help of a binocular magnifying glass. The presence of the bridges was confirmed in 41% of the researched material, most frequently above the anterior interventricular branch. The length of the bridges varies in the range of 2.3-42.8 mm, thickness 1.0-3.8 mm, angle between long axis of muscle fibres and long axis of the crossed vessel from 5 degrees to 90 degrees.

Costs of revascularization over eight years in the randomized and eligible patients in the Emory Angioplasty versus Surgery Trial (EAST).

The Emory Angioplasty versus Surgery Trial (EAST) was a randomized trial that compared, by intention to treat, the clinical outcome and costs of percutaneous transluminal coronary angioplasty (PTCA) and coronary bypass grafting (CABG) for multivessel coronary artery disease. We present the findings of the economic analysis of EAST through 8 years of follow-up and compare the cost and outcomes of patients randomized in EAST versus patients eligible but not randomized (registry patients). Charges were assessed from hospital UB82 and UB92 bills and professional charges from the Emory Clinic. Hospital charges were reduced to cost through step-down accounting methods. All costs and charges were inflated to 1997 dollars. Costs were assessed for initial hospitalization and for cumulative costs of the initial hospitalization and additional revascularization procedures up to 8 years. Total 8-year costs were $46,548 for CABG and $44,491 for PTCA (p = 0.37). Cost of CABG in the eligible registry group showed a pattern similar to that for randomized patients, but total cost of PTCA was lower for registry patients than for randomized patients. Thus, the primary procedural costs of CABG are more than those for PTCA; this cost advantage, given the limits of measurement, is largely or even completely lost for randomized patients over the course of 8 years because of additional procedures after a first revascularization by PTCA.

Targeting patients undergoing angioplasty for thrombus inhibition: a cost-effectiveness and decision support model.

BACKGROUND: In recent clinical trials, glycoprotein IIb/IIIa blockers have demonstrated effectiveness in preventing adverse events after angioplasty in high-risk patients. However, uncertainty exists regarding the cost-effective selection of patients to receive antiplatelet therapy. METHODS AND RESULTS: All 4962 patients at Emory University Hospitals who underwent coronary intervention procedures (n=6062) from 1993 to 1995 were studied. Multivariate models to predict death and the composite of death, Q-wave and non-Q-wave myocardial infarction, and emergency additional revascularization were developed. Hospital costs and professional costs were determined. A cost-effectiveness analysis with therapy targeted to high-risk patients was performed. If patients with a >5% probability of events received antiplatelet therapy that reduced events by 24% and cost $1000, 40.1% of patients would receive therapy; complications would be reduced from 6.39% to 5.37%, and cost would increase $261 from $10343 to $10604, or $25504 per event prevented. The marginal cost per event prevented by moving from a 7% to a 5% probability of an event cutoff would be $57 799. CONCLUSIONS: For high-risk patients, there may be cost savings; for low-risk patients, therapy may not be cost effective; and for patients in the midrange (between 5% and 7% probability of an adverse event), events may be prevented at an acceptable level of cost.