Temporal Endpoint Research Articles

Denominal conversion verbs and the ‘verb + it’ construction in English

In English, a number of verbs enter a noteworthy, though understudied, combination with a morpheme it, which evidently lacks a referential function. Among these verbs, there are quite a few which were formed from nouns by means of conversion (e.g. to bus it, to au pair it, to verse it, to newspaper it). While some authors assume that the expletive morpheme it in direct-object position functions to enhance a verb’s transitivity, the most recent diachronic study has shown that its influence on transitivity is rather marginal. If transitivization is not the driving force behind the use of the ‘verb + it’ construction, the question as to other functions arises. The aim of this article is to present a new proposal according to which the expletive element is primarily (though not exclusively) an aspectual marker, which, in contrast to the bare verb, expresses telicity (e.g. to bus vs. to bus it). In this function, this element provides the verb it complements with a temporal endpoint. Proceeding from a distinction between (a)telicity and (un)boundedness drawn in the pertinent literature, it will be shown that this endpoint may or may not actually be reached. The aspectual function of the expletive element it is assumed here to co-exist with other functions identified in the few previous works and in the present study. These functions, which are independent of telicity, comprise the expression of necessity, the intensification of activities, the preservation of the verse metre especially in literary texts, and the support of the verbal status of innovative or weakly established denominal conversion verbs.

Toward a Super-COP? Timing, Temporality, and Rethinking World Climate Governance

Toward a Super-COP? Timing, Temporality, and Rethinking World Climate Governance

Longitudinal study of patients with antimelanoma differentiation-associated gene 5 antibody-positive dermatomyositis-associated interstitial lung disease.

To describe the 8-year longitudinal study and long-term prognosis of a large inception cohort of anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive (MDA5+) DM-interstitial lung disease (ILD) patients. In total, 216 patients diagnosed with MDA5+ DM-ILD were enrolled and followed up to analyse long-term survival rate. Demographic and clinical variables were collected at baseline and each temporal end point. Seventy patients who survived the first year were analysed for the long-term serological and respiratory outcomes. A total of 85 patients (39.3%) died during the follow-up period up to 96 months, with 89% of the deaths occurring in the first year after diagnosis. Long-term outcome was reported in 70 patients. Serological markers including anti-MDA5 antibody showed significant improvement with time. Radiographic findings and pulmonary function also improved notably in the follow-up period, especially in rapidly progressive ILD group, as measured by high-resolution computed tomography imaging scores, the estimated forced vital capacity, estimated diffusing capacity of lung carbon monoxide and dyspnoea scores. Early application of anti-fibrosis therapy helped to improve long-term pulmonary function. MDA5+ DM-ILD patients had a high mortality rate despite aggressive treatment. Patients who survived the first year usually showed a significant improvement in serological markers and pulmonary function during the long-term follow-up.

The Frontier Complex: Geopolitics and the Making of the India-China Border, 1846–1962 by Kyle J. Gardner

Reviewed by: The Frontier Complex: Geopolitics and the Making of the India-China Border, 1846–1962 by Kyle J. Gardner Benjamin Holt The Frontier Complex: Geopolitics and the Making of the India-China Border, 1846–1962. By Kyle J. Gardner. Cambridge: Cambridge University Press, 2021. xxi + 280 pp. ISBN 978-1-108-84059-0. $99.00 (hardcover). A central aim of Kyle Gardner's The Frontier Complex is to demonstrate how colonial border-making shaped ideas about territory that created legacies still felt in contemporary Asia (p. xvi). Supplementary ambitions are to bring Ladakh into greater focus within histories of South Asia (p. 20) and amalgamate top-down narratives of border-making with ground-level experiences. The book delivers on these aims. To do so, Gardner traces the history of the frontier to reveal how colonial concerns with geography and security created the foundation for the postcolonial borderland. Thus, the book rejects the stasis of borders in favor of an in-depth temporal analysis of developments in the northwest Himalaya, with primary focus on Ladakh. A core argument made by Gardner is that the creation of a borderland is not merely a routine exercise in map-making. Rather, the process is critical for understanding ways that "geography, politics, and power" are understood (p. 2). When this historical process is recognized, notable insights follow. For instance, Gardner is particularly keen to stress the ramifications of the "new, geopolitical way of seeing space" that dominated British thinking from the late nineteenth century (p. 184). The focus on security was propelled by colonial anxieties and this—alongside the inability to properly demarcate a clear boundary—produced lasting effects. This conundrum proved to be a key factor behind the Sino-Indian war of 1962, the temporal endpoint of the book. [End Page 532] The notion of the "frontier complex"—that is the various practices used by colonial officials, from surveys and mapping, to construction, information, and regulation (p. 21)—provides the framework for analysis. The first chapter covers the diverse ways the region was "seen" before the British arrival, suggesting that "Ladakh" was—in a sense—a colonial construct. The second then suggests the colonial state developed both natural and political understandings of the region but failed to construct a "scientific frontier" regardless.1 This desire to politicize geography is a continuing theme in chapters three and four as roadbuilding and colonial texts take centre stage. The former was a conduit of imperial security; the latter reflected the colonial vision of territory. Chapters five and six then delve into the rise of geopolitical thought from the 1880s, as colonial anxieties clashed with previous ideas about exploration and commercialization. The final chapter then confronts the postcolonial legacies of the frontier complex. A key strength of The Frontier Complex is its advancement beyond top-down narratives of border-making to continually examine groundlevel interactions with colonial visions of space. For instance, chapter four provides a compelling overview about how lopchak and chaba—essentially tributes paid between Ladakh and Lhasa—proved problematic for colonial governance and prestige (pp. 158–165). This approach is made possible by a rich and diverse source base. The only issue this reviewer would highlight relates to the 1962 war. Considering how heavily it weighs upon the book, the immediate prelude to war is mostly overlooked (pp. 248–250). A more concerted explanation for the midand short- term dynamics could be provided, narrated alongside the longer-term structural factors that Gardner's book reveals. This would help to recalibrate traditional narratives of the conflict, providing more convincing context for the diplomatic failures leading to 1962, of which Gardner is critical (p. 61). Despite this relatively minor area of contention, The Frontier Complex is a richly researched work that provides significant insight for several fields. This is clearest for borderlands studies and adds to a growing repertoire of historically focused analyses in recent years.2 [End Page 533] Viewing borders as something more than "hard territorial lines" is a clear point of departure for the subfield, but Gardner's book reinforces the benefits of understanding the temporal development of the borderland to reveal how spaces are conditioned by the changing interests of associated polities...

A Study on Temporal Structure Characteristics of V in ‘v+ Dao’ Structure from the Cognitive Perspective

The ‘v+Dao’ is a structure related to the action process and the end point in the modern Chinese. This paper discussed the temporal process of verbs in ‘v+Dao’ from the cognitive perspective, especially the relationship between ‘Dao’ and the temporal end point of verbs. First of all, ‘v+Dao’ can be classified into the spatial meaning, the time meaning, the degree meaning and the result meaning. It can be discovered from the event fusion of the spatial meaning structure that there exist completely different temporal processes of verbs and events in this structure. On this basis, this paper studied the temporal characteristics of verbs in ‘v+Dao’, including the time meaning, the degree meaning and the result meaning. It is believed that the ‘end point’ indicated by ‘Dao’ in the result-meaning structure is the natural logic end point of verbs. That is, the fixed end point of the internal process. However, the external end point of verbs indicated by ‘Dao’ in other structures changed with varying events. This paper attempted to discuss the temporal process characteristics of verbs in this structure from the perspective of ‘cognitive-syntax’ interface aiming to explore the syntactic and semantic relationship between V and ‘Dao’ as well as the study on the part of speech of ‘Dao’.

Temporal Invariance in SCA6 Is Related to Smaller Cerebellar Lobule VI and Greater Disease Severity.

Regulating muscle force and timing are fundamental for accurate motor performance. In spinocerebellar ataxia type 6 (SCA6), there is evidence that individuals have greater force dysmetria but display better temporal accuracy during fast goal directed contractions. Here, we test whether greater temporal accuracy occurs in all individuals with SCA6, and can be explained by lesser temporal variability. Further we examine whether it is linked to disease severity and specific degenerative changes in the cerebellum. Nineteen human participants with SCA6 (13 woman) and 18 healthy controls performed fast goal-directed ankle dorsiflexion contractions aiming at a spatiotemporal target. We quantified the endpoint control of these contractions, gray matter (GM) integrity of the cerebellum, and disease severity using the International Cooperative Ataxia Rating Scale (ICARS). SCA6 individuals exhibited lower temporal endpoint error and variability than the healthy controls (p = 0.008). Statistically, SCA6 clustered into two distinct groups for temporal variability. A group with low temporal variability ranging from 10 to 19% (SCA6a) and a group with temporal variability similar to healthy controls (SCA6b; 19-40%).SCA6a exhibited greater disease severity than SCA6b, as assessed with ICARS (p < 0.001). Lower temporal variability, which was not associated with disease duration (R2 = 0.1, p > 0.2), did correlate with both greater ICARS (R2 = 0.3) and reduced GM volume in cerebellar lobule VI (R2 = 0.35). Other cerebellar lobules did not relate to temporal variability. We provide new evidence that a subset of SCA6 with greater loss of GM in cerebellum lobule VI exhibit temporal invariance and more severe ataxia than other SCA6 individuals.SIGNIFICANCE STATEMENT Variability is an inherent feature of voluntary movement, and traditionally more variability in the targeted output infers impaired performance. For example, cerebellar patients present exacerbated temporal variability during multijoint movements, which is thought to contribute to their motor deficits. In the current work, we show that in a subgroup of spinocerebellar ataxia type 6 individuals, temporal variability is lower than that of healthy controls when performing single-joint fast-goal directed movements. This invariance related to exacerbated atrophy of lobule VI of the cerebellum and exacerbated disease severity. The relation between invariance and disease severity suggests that pathological motor variability can manifest not only as an exacerbation but also as a reduction relative to healthy controls.

How measures of agricultural landscape patterns are affected by crop rotation dynamics

Landscape patterns have been measured as a fundamental part of landscape ecology, especially with increasing computational power and availability of landcover data. Among the challenges associated with landscape measurement is identifying the appropriate scale of application, both temporal and spatial. Measurement of landscape patterns in highly-dynamic landscapes is especially challenged by temporal scale selection. This short communication focuses on how landscape pattern measurements vary in response to normal variability in a highly-dynamic landscape For a small agricultural landscape with known crop rotation dynamism sequences, a simulation model provided 30 years of crop rotations. These 30 different landscapes were measured with landscape pattern measurements and the variability of the measurements was assessed. Almost half of the measurement values were outliers, and 12 of the 30 years had at least one outlier landscape pattern measurement value, even though the basis of landscape change was a normative agricultural practice. For a consistent but dynamic landscape, some landscape measurements or simulation years had high variability, demonstrating that inferences from highly-dynamic landscapes need to be based on fine-resolution time steps. The application of landscape pattern measurements continues to be a common method in landscape ecology, and temporal dimensions are key to detecting change and what might be causing or responding to that change. The temporal resolution of change implies that highly-dynamic landscapes require more-frequent sampling, and that comparisons for agricultural landscapes over long time periods requires more than a single temporal endpoint.

Variational principle and time-space finite element method for dynamic thermoelasticity based on mixed convolved action

Abstract A new variational formulation is proposed for time-domain analysis of initial/boundary value problems of dynamic thermoelasticity. By using the concept of mixed convolved action, the difficulties with dissipative phenomena and proper representations of the temporal end point conditions can be overcome to create a true stationary variational principle. After an elementary illustrative development for a lumped parameter thermoelastic model, the convolved action functional for linear thermoelastic continuum is written directly in terms of mixed variables, which include displacements and the impulses of stress, temperature and heat flux. Unlike previous variational approaches, based for example upon a generalization of Hamilton's principle , the present mixed convolved action formulation allows direct application of finite element methodology in both space and time. Here, simple linear shape functions are employed for the temporal representations. Meanwhile, standard three-noded triangular elements are used in the present two-dimensional numerical implementation. Several computational examples are considered to test this original approach and to investigate interesting aspects of coupled dynamic thermoelastic response.

Vitrectomy in the management of diabetic macular edema in treatment-naïve patients

ObjectiveTo determine the efficacy of vitrectomy in eyes with treatment-naïve diabetic macular edema (DME). MethodsConsecutive patients with treatment-naïve DME who underwent pars plana vitrectomy with internal limiting membrane peeling at a single institution were identified from the electronic medical records. Morphologic and visual acuity changes from baseline were analyzed at both the primary temporal endpoint (6 months) and the final examination with the investigators. The primary outcome measures included changes in best-corrected visual acuity (BCVA) and central retinal thickness (CRT). ResultsForty-four eyes of 44 patients were included in this retrospective study. The mean BCVA improved significantly from baseline until the 6-month primary endpoint (1.35 logMAR vs 0.83 logMAR, p < 0.001) and stabilized through the final examination (0.77 logMAR). The BCVA improved by at least 0.1, 0.3, and 0.6 logMAR in 26 (60%), 24 (55%), and 14 (32%) of eyes, respectively, whereas it worsened by 0.3 logMAR in only 1 (2%) eye. Final BCVA correlated inversely with duration of diabetes (p = 0.01), presence of an epiretinal membrane (p = 0.02), and initial visual acuity (p = 0.03). Mean CRT decreased significantly from baseline through 6 months (595 µm vs 266 µm; p < 0.001), and edema recurred in only 3 eyes (6%), one of which was subsequently treated with intravitreal bevacizumab. ConclusionsPars plana vitrectomy significantly improves macular edema and visual acuity in eyes with treatment-naïve DME. Prospective randomized trials are needed to better determine the efficacy of early vitrectomy.

Beyond Death’s (and Conception’s) Door: The Unsettling Limitations of Incarnate Existence

ABSTRACTThe psychological effects of contemplating one’s death have received much empirical attention, but the impact of thinking about one’s conception—the other temporal endpoint of physical existence—has not. Across three experiments, reflecting on conception or death (vs. a neutral topic) led to increased framing of sexual reproduction as miraculous and sacred, intensified belief in discarnate immortality, and a greater desire to experience a discarnate state that offered no direct assurance of literal immortality. Thinking about death uniquely evoked greater anxiety as well as greater desire for an experience that offered assurance of literal immortality, congruent with the tenets of terror management theory. Nevertheless, the parallel effects evoked by reflecting on conception and death also suggest that both amplify the aversive salience of the limitations inherent to physical existence, such that people respond by seeking experiences and adjusting attitudes/beliefs to divert attention from the physical body.

Juvenal, Satires 3.74 and Suetonius

The rhetorician Isaeus mentioned by Juvenal in Satires 3 was almost certainly not discussed by Suetonius, despite Giorgio Valla’s note to this passage, due to the temporal endpoint of the Illustrious Men . A similar error can be found in Valla’s use of Suetonius for Passienus Crispus on the authority of the same “Probus.” The Suetonian fragment on Isaeus should no longer be accepted as it stands. Suetonius probably instead discussed the fourth-century orator Isaeus, following Hermippus as his source.

The land‐use legacy effect: Adding temporal context to lake chemistry

We investigated land use and land cover (LULC) effects, i.e., effects that perpetuate beyond an expected or perceived temporal endpoint, on the chemistry of 35 lakes in the Huron River Watershed, Michigan. Temporal changes in five time steps of LULC were represented by principal components, which were entered hierarchically into a multiple regression to predict water chemistry. We compared model fit using Akaike weights, and model predictive ability using R2, for models representing LULC from a single time up to models that included LULC from all five time steps. The regressions using only the most recent LULC provided the best fit for phosphorus species, but legacy models provided a better fit for all nine other lake water characteristics. Models for all species of nitrogen, calcium, silica, and sulfate showed an intermediate legacy effect and incorporated some historic LULC. Models for conservative ions showed the longest legacy effect, incorporating all five time steps, and had the highest explanatory power of all water chemistry characteristics in our study. Legacy timescales are likely influenced by biological reactivity: highly reactive elements had relatively short legacy timescales and conservative ions had the longest legacy timescales.

PPI Dosing Patterns for Recently Bleeding Gastroduodenal Ulcer Disease

Purpose: Studies have demonstrated equivalent healing rates in patients receiving standard (20 mg) versus higher dose omeprazole taken for uncomplicated gastroduodenal ulcer disease (GD). Many experts also recommend standard dose, once daily omeprazole or equivalent for non-acute, recently bleeding GD. We sought to determine PPI dosing patterns for recently bleeding, GD within a single-center, university hospital setting. Methods: Single-center chart review of patients discharged on PPI therapy after endoscopic confirmation of recently bleeding, GD between the years 2003–2007. Inclusion criteria: adults 18–80 years old, acutely or recently bleeding GD confirmed endoscopically, PPI prescribed at hospital discharge. Exclusion criteria: prior h/o GD, h/o GERD/esophagitis, Zollinger-Ellison syndrome, GI malignancy, confirmed or suspected intestinal metaplasia of esophagus, positive/indeterminate H. pylori testing. Ascertainment of PPI type and dose was made from discharge summary or, when unavailable, endoscopy reports. Results: 383, 209 and 57 subjects with recently bleeding gastric, duodenal and dual location ulcers were identified, respectively, over the 5 year study period. Of these, 39, 31 and 10, respectively, met pre-specifed study criteria. 69%, 68% and 100%, respectively, were prescribed PPIs at discharge in excess of standard dosing (see Table). 95% of subjects prescribed PPIs with suprastandard dosing were placed on a twice-daily schedule. Among the entire study cohort, 50% were on NSAIDs, 17% had high-risk stigmata at time of endoscopy. In cases of active bleeding, patients were discharged no sooner than 24 hours from the time of endoscopy. There was no significant trend from year to year in the number of patients receiving PPIs in excess of standard dosing (χ2= 0.61). In the majority of cases no temporal endpoint of therapy was given at the time of PPI prescription. Conclusion: At a university hospital, the majority of patients with recently bleeding GD were discharged on PPI dosages in excess of that generally considered sufficient for ulcer healing. These data build upon the growing recognition of inappropriate PPI usage in a variety of practice settings. A more rational approach to PPI dosing for GD may have many beneficial consequences including significant cost savings.Table

Twenty-eight–day mortality in critically ill surgical patients is an imprecise temporal end-point measure for in-hospital mortality

Background The purpose of this study was to determine the incidence of deaths occurring beyond 28 days in critically ill surgical patients and to identify the proportion of these deaths attributable to the original disease process. Methods Analysis of 1,360 subjects admitted to a surgical intensive care unit during a 2 year period. Demographics, indication(s) for admission, comorbidities, mortality rate, multiorgan failure development, and cause of death was obtained. Results Mortality rate in the surgical intensive care unit was 12%. Twenty % of deaths occurred more than 28 days after hospital admission with 76% of deaths related to admission diagnosis. By day 34, 95% of mortalities had occurred. Conclusions The 28-day time period used to assess efficacy of therapeutic interventions and to define mortality in the context of quality audits should be questioned. If these findings are validated in other centers another temporal end point for in-hospital mortality should be considered.

Visual and musculoskeletal underpinnings of anchoring in rhythmic visuo-motor tracking

Anchoring, that is, a local reduction in kinematic (i.e., spatio-temporal) variability, is commonly observed in cyclical movements, often at or around reversal points. Two kinds of underpinnings of anchoring have been identified—visual and musculoskeletal—yet their relative contributions and interrelations are largely unknown. We conducted an experiment to delineate the effects of visual and musculoskeletal factors on anchoring behavior in visuo-motor tracking. Thirteen participants (reduced to 12 in the analyses) tracked a sinusoidally moving visual target signal by making flexion–extension movements about the wrist, while both visual (i.e., gaze direction) and musculoskeletal (i.e., wrist posture) factors were manipulated in a fully crossed (3 × 3) design. Anchoring was affected by both factors in the absence of any significant interactions, implying that their contributions were independent. When gaze was directed to one of the target turning points, spatial endpoint variability at this point was reduced, but not temporal endpoint variability. With the wrist in a flexed posture, spatial and temporal endpoint variability were both smaller for the flexion endpoint than for the extension endpoint, while the converse was true for tracking with the wrist extended. Differential anchoring effects were absent for a neutral wrist posture and when gaze was fixated in between the two target turning points. Detailed analyses of the tracking trajectories in terms of velocity profiles and Hooke’s portraits showed that the tracking dynamics were affected more by wrist posture than by gaze direction. The discussion focuses on the processes underlying the observed independent effects of gaze direction and wrist posture on anchoring as well as their implications for the notion of anchoring as a generic feature of sensorimotor coordination.

Recent histories of six productive lakes in the Irish Ecoregion based on multiproxy palaeolimnological evidence

Palaeolimnological data from six mesotrophic, eutrophic and hypertrophic lakes in the Irish Ecoregion, in the form of microfossil (cladocera, diatoms and pollen) and sediment chemistry data from radiometrically dated sediment cores, were used to reconstruct past variations in lake water quality and catchment conditions. Basal sediments from sediment cores from the six sites ranged in age from the late 18th century to the early 20th century. A weighted averaging partial least squares regression model was developed to reconstruct past epilimnetic total phosphorus concentrations. The results indicate that all but one of the study sites currently are in a far more productive state compared with the beginning of the sediment core record and that those same five lakes have experienced accelerated enrichment post c. 1980. Two of the sites demonstrated long-term enrichment, in one case beginning in the late 19th century, while both eutrophication and oligotrophication have occurred at three sites. The results highlight the difficulties in applying a general temporal end-point for reference conditions and demonstrate that productive lakes in the Irish Ecoregion have complex, locally specific and often long histories of enrichment. These may not be responsive to reduced external loadings of phosphorus and, as a result, restoration could prove particularly challenging. The results also provide evidence of the ways in which palaeolimnological techniques can assist implementation of the EU Water Framework Directive.

Dynamics of sensorineural hearing loss after head trauma.

To estimate the temporal endpoint of permanent sensorineural hearing loss after head trauma. Retrospective observational case study. In patients with sensorineural hearing loss caused by head trauma, 1,741 ears were studied. A follow-up survey of audiograms in patients with sensorineural hearing loss after head trauma was performed for up to 4 years from the date of injury. Each patient's audiograms were compared according to a severity score that specifically classified hearing loss that was associated with acoustic trauma. Either improvement or deterioration of the early posttrauma hearing loss occurred during the first year after head trauma. Thereafter, hearing levels could be expected to remain stationary. Fluctuation in hearing after head trauma may take place within the first year after trauma, after which the associated hearing loss should be considered to be stabilized.

Knowledge used in duration judgments of two moving objects

Forty-nine undergraduates observed two cars traveling in the same direction on a CRT display for various duration. They then chose the car that they believed had run longer, and gave the reason for their choice. There were three types of tasks. Correct judgment was possible for the first type, by logically applying either of two pieces of knowledge about duration: "duration equals temporal end point minus temporal start point" (Knowledge alpha) or "duration equals distance divided by speed" (Knowledge beta). Knowledge alpha alone was useful for the second type, while only Knowledge beta led to correct judgment for the third. Main results were as follows: (1) Undergraduates were more likely to use Knowledge alpha than beta regardless of the types. (2) None of repeatedly making judgment, thinking about reasons for judgment, or receiving failure feedback was very helpful making participants become aware of necessity of using Knowledge beta for the third type. (3) Only some 20% of undergraduates were able to use proper knowledge specifically required for each type.

Intermediate-term clinical outcome following transmyocardial laser revascularization in patients with refractory angina pectoris.

This study was conducted to examine the intermediate-term clinical outcomes in patients with refractory angina pectoris treated with transmyocardial laser revascularization (TMR) at our institution. TMR is an alternative surgical technique for the treatment of myocardial ischemia and angina pectoris not amenable to conventional percutaneous or surgical revascularization. Limited data exist evaluating the natural history and duration of clinical improvement in angina pectoris following TMR. Thirty-four patients with severe coronary artery disease unsuitable for treatment with standard revascularization techniques underwent TMR in myocardial regions determined to be ischemic by preoperative SPECT (201)Tl perfusion imaging following dipyridamole stress. Patients were assessed postoperatively at 3, 6, and 12 months for clinical outcomes including death, myocardial infarction, functional class of angina pectoris, and hospitalizations for unstable angina. Myocardial perfusion imaging by (201)Tl scintigraphy was also assessed at these temporal end points. Overall mortality at 1 year was 14.7% (n=5). Nonfatal myocardial infarction occurred in 3 patients (8.8%). Among the patients with complete 12-month follow-up (n =27), mean anginal class improved from 3.5+/-0. 5 pre-TMR to 2.8+/-0.7 and 2.5+/-0.7 at 3 and 6 months, respectively, and 2.8+/-0.9 at 12 months. Overall improvement in angina pectoris was sustained at 1 year by at least one functional class in 50% of patients. Mean hospitalizations per year for unstable angina declined from 2.4+/-1.6 pre-TMR to 1.7+/-2.0 post-TMR (P=0.01). There was no significant improvement in perfusion by SPECT (201)Tl imaging at any temporal end point post-TMR. Despite the lack of demonstrable improvement in perfusion by SPECT (201)Tl imaging, TMR improved the functional class of angina pectoris in patients with end stage coronary artery disease to a modest degree. Although the maximal benefit in symptoms occurred at 6 months post-TMR, mild sustained clinical improvement above baseline was evident in 50% of patients at 1 year.

Intermediate-Term Clinical Outcome Following Transmyocardial Laser Revascularization in Patients With Refractory Angina Pectoris

Background —This study was conducted to examine the intermediate-term clinical outcomes in patients with refractory angina pectoris treated with transmyocardial laser revascularization (TMR) at our institution. TMR is an alternative surgical technique for the treatment of myocardial ischemia and angina pectoris not amenable to conventional percutaneous or surgical revascularization. Limited data exist evaluating the natural history and duration of clinical improvement in angina pectoris following TMR. Methods and Results —Thirty-four patients with severe coronary artery disease unsuitable for treatment with standard revascularization techniques underwent TMR in myocardial regions determined to be ischemic by preoperative SPECT 201 Tl perfusion imaging following dipyridamole stress. Patients were assessed postoperatively at 3, 6, and 12 months for clinical outcomes including death, myocardial infarction, functional class of angina pectoris, and hospitalizations for unstable angina. Myocardial perfusion imaging by 201 Tl scintigraphy was also assessed at these temporal end points. Overall mortality at 1 year was 14.7% (n=5). Nonfatal myocardial infarction occurred in 3 patients (8.8%). Among the patients with complete 12-month follow-up (n =27), mean anginal class improved from 3.5±0.5 pre-TMR to 2.8±0.7 and 2.5±0.7 at 3 and 6 months, respectively, and 2.8±0.9 at 12 months. Overall improvement in angina pectoris was sustained at 1 year by at least one functional class in 50% of patients. Mean hospitalizations per year for unstable angina declined from 2.4±1.6 pre-TMR to 1.7±2.0 post-TMR ( P =0.01). There was no significant improvement in perfusion by SPECT 201 Tl imaging at any temporal end point post-TMR. Conclusions —Despite the lack of demonstrable improvement in perfusion by SPECT 201 Tl imaging, TMR improved the functional class of angina pectoris in patients with end stage coronary artery disease to a modest degree. Although the maximal benefit in symptoms occurred at 6 months post-TMR, mild sustained clinical improvement above baseline was evident in 50% of patients at 1 year.