Brugada Phenocopy Associated With Toxic Myocarditis due to Aluminum Phosphide: A Case Report

Acute coronary syndromes

Improvement in left ventricular (LV) function in patients with idiopathic dilated cardiomyopathy (DCM) by medical treatment has been suggested. Thus, it is important to evaluate which patients will respond to medical therapy. Positron emission tomography (PET) with fluorine-18 fluoro-2-deoxyglucose (FDG) and cardiac catheterization were performed in 20 patients with DCM before the initiation of medical therapy. The regional myocardial glucose utilization rate (rMGU) was measured with FDG PET. Subjects were divided into two groups, group 1 (event-free patients, n=10) and group 2 (clinical cardiac events, n=10). Haemodynamic and PET parameters before the initiation of medication were compared between the two groups and between patients with and patients without improvement in LV function. Ejection fraction (EF) was significantly higher in group 1 (35.8%+/-9.0%) than in group 2 (24.8%+/-7.0%) and LV end-diastolic pressure (LVEDP) was significantly lower in group 1 (8.4+/-1.7 mmHg) than in group 2 (11.6+/-3.5 mmHg). Average rMGU (mg min-1 100 g-1) was similar in group 1 (11.2+/-2.5 mg min-1 100 g-1) and group 2 (11.2+/-2.9 mg min-1 100 g-1), while %CV of rMGU was significantly lower in group 1 (11.1%+/-6.3%) than in group 2 (29. 9%+/-13.9%, P<0.01). Furthermore, LV function normalized in seven patients in group 1. In these seven patients, EF (35.1%+/-10.9%), LVEDP (8.2+/-2.0 mmHg) and average rMGU (11.8+/-2.7 mg min-1 100 g-1) were comparable with those in patients without LV functional improvement (EF: 31.6%+/-9.1%; LVEDP: 10.7+/-3.3 mmHg; average rMGU: 10.8+/- 2.7 mg min-1 100 g-1). However,% CV of rMGU in patients with LV functional improvement (9.6%+/-5.6%) was significantly lower than in those without such improvement (26.3%+/-14.1%, P<0.01). %CV of rMGU <13.6% predicted prognosis with a sensitivity of 80%, a specificity of 100% and an accuracy of 90%. %CV of rMGU <13.6% also predicted improvement in LV function, with a sensitivity of 75%, a specificity of 92% and an accuracy of 85%. However, EF failed to predict improvement of LV function. In is concluded that homogeneous myocardial glucose utilization rate can predict both prognosis and improvement in LV function achieved by medical therapy in patients with DCM.

Previous studies have demonstrated improvement of regional wall motion and global left ventricular function after successful recanalization of chronic total occlusion in coronary artery. However, the difference of benefits of recanalization between infarct site and noninfarct site is unknown. This study assessed the changes in left ventricular ejection fraction, regional wall motion after successful angioplasty of chronic total occlusions with or without previous myocardial infarction. This study also evaluated the factors that influenced the outcome of left ventricular function. We retrospectively studied 75 patients with a successfully recanalized chronic total occlusion in native coronary artery. Left ventriculograms were obtained at baseline and after 6 months. Global and regional left ventricular function were determined. The patients were divided into two groups. Group 1 comprised patients without previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Group 2 comprised patients with previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Left ventricular ejection fraction increased from 53.2% +/- 16.3% at baseline to 57.3% +/- 20.1% at 6-month follow-up in the whole group (P = 0.001). In group 1 patients, the evolution of left ventricular (LV) ejection fraction increased from 59.5% +/- 13.7% to 67.3% +/- 14.6% (P < 0.001). In group 2 patients, the evolution of LV ejection fraction increased, but not significantly, from 48.9% +/- 16.2% to 50.5% +/- 16.9% (P = NS). The evolution of LV ejection fraction increased from 47.6% +/- 17.4% to 50.8% +/- 17.5% (P < 0.05) in the subgroup of recanalization in infarct-related vessel that had rich collateral circulation and had long-term patency. The regional wall motion all significantly improved in group 1 patients (P < 0.05). The regional wall motion did not change in group 2 patients (P = NS). The influence of recanalization of chronic coronary occlusions on the improvement of left ventricular global function was different between myocardial infarction and nonmyocardial infarction patients. The left ventricular function did not improve in myocardial infarction patient. Regional wall motion improved in patients without previous myocardial infarction. For reliable improvement of left ventricular function after recanalization of chronic total occlusions, evidence (not only by symptom or treadmill test) of viable myocardium in recanalized vessel is important. It is also important to keep patency of infarct-related vessel that has good collateral circulation for improving the left ventricular function.

Scaffold Delivery of Neonatal Cardiomyocyte Results in Prolonged Cellular Survival and Improvements in Left Ventricular Function in Rats with Chronic Heart Failure

P3699Circulating pro-apoptotic microRNA-122 correlates with left ventricular function (LVEF) improvement after transcatheter aortic valve replacement and influence cardiomyocyte function via microvesicle

Brain (B-type) natriuretic peptide (BNP) is a 32 amino acid peptide that is synthesized and released predominantly from ventricular myocardium in response to myocyte stretch. Like atrial natriuretic peptide (ANP), BNP seems to have almost exclusively beneficial physiological properties, including balanced vasodilation, natriuresis, and inhibition of both the sympathetic nervous system and the renin-angiotensin-aldosterone axis. Attempts to exploit these properties for therapeutic benefit has led to the development of recombinant human BNP (nesiritide) for the acute treatment of decompensated heart failure, and also of novel compounds that inhibit neutral endopeptidase, an enzyme that is partially responsible for BNP degradation. See p 2913 In patients with heart failure, the cardiac neurohormonal system is activated, and circulating plasma levels of ANP, BNP, and the N-terminal fragments of their prohormones (N-proANP and N-proBNP) are elevated. Compared with ANP and N-proANP, BNP and N-proBNP undergo a greater proportional rise in disease states (ie, higher “signal-to-noise” ratio), and thus have emerged as the preferred biomarkers for clinical development. With commercially available assays now available, measurement of BNP or N-proBNP can be integrated readily into the care of patients with suspected heart failure. Although data are limited, BNP and N-proBNP seem to provide qualitatively similar information, and for purposes of this editorial, will be referred to interchangeably. Incorporation of BNP measurement into the clinical evaluation facilitates the diagnosis of heart failure due to either left ventricular (LV) systolic or diastolic dysfunction; a normal BNP level virtually rules out the diagnosis of decompensated heart failure, whereas a markedly elevated BNP has a high positive predictive value for heart failure.1 Although BNP levels are correlated with age, sex, intracardiac filling pressures, LV mass and ejection fraction (LVEF), renal function, and symptoms, BNP provides prognostic information in patients with heart failure that is independent of these variables.2 …

Although pioneering preclinical research on the use of cell therapy for cardiac regeneration was conducted in the last quarter of the 20th century,1,2 a preponderance of advances have occurred in the 21st century, making this a relatively young field. In the first important clinical trial of cardiac cell therapy, begun in 2001, Menasche et al3 implanted autologous skeletal myoblasts into postinfarct scar at the time of coronary artery bypass surgery. Although the transplanted cells remained viable and exhibited contraction, they formed the nidus for serious ventricular tachyarrhythmias, which led to premature discontinuation of the trial. Despite this outcome, the trial energized the field, accelerating both preclinical and clinical research, albeit not with skeletal myoblasts. The extensive progress in cardiac regeneration is reviewed in this Compendium, and as occurs frequently in science, important observations have led to more questions and challenges (Table). View this table: Table. Important Challenges to Cell Therapy for Cardiac Regeneration Many cell types have been evaluated as candidates for cardiac regeneration. Among the earliest clinical trials, Zeiher’s group infused autologous bone marrow-derived progenitor cells into the coronary arteries of patients with acute,4 as well as healed myocardial infarction (MI)5 and reported improvements in left ventricular (LV) function. However, these results have not been fully confirmed by later studies, as pointed out in the review in the Compendium by Banarjee, Bolli, and Hare.6 Pittenger et al7 were among the first to direct attention to bone marrow-derived (stromal) mesenchymal stem cells (MSCs), emphasizing that these cells proliferated extensively in culture and suggesting that they could be attractive candidates for transplantation. In 2004, Chen et al8 reported that intracoronary infusion of autologous bone marrow-derived MSCs improved cardiac function. Zimmet and Hare pointed out that MSCs lack histocompatibility type II markers and elude rejection by …

Contrast ventriculograms of 542 patients treated with intravenous thrombolytic agents for acute myocardial infarction were examined to define changes in left ventricular ejection fraction and regional wall motion that occur during the first week after reperfusion therapy for acute myocardial infarction and define clinical, acute angiographic and treatment variables related to improvement in global and regional left ventricular function. Intravenous tissue-type plasminogen activator and/or urokinase was administered to 805 patients during acute myocardial infarction. Mean time from symptom onset to thrombolytic therapy was 3 hours (22 patients received therapy within the first hour). Acute and 7-day catheterization were performed. Paired left ventricular ejection fraction and centerline regional wall motion were available in 542 patients (67%). Stepwise, multivariable analysis of clinical, acute angiographic and treatment variables was used to develop two models: One related to improvement in left ventricular ejection fraction, and the second related to improvement in infarct zone regional function. Left ventricular ejection fraction did not change (51.2 +/- 11.1% for acute versus 51.9 +/- 11.0% for 1 week, p = 0.19). Improvement in infarct zone regional function was modest (14%) at 1 week (-2.54 +/- 1.07 standard deviation per chord for acute versus -2.17 +/- 1.24 at 1 week, p < 0.001). Subgroup analysis demonstrated modest improvement in ejection fraction (1.4 +/- 9.5%) and greater improvement in infarct zone function (19%) in patients with successful sustained reperfusion at 1 week. Depressed left ventricular ejection fraction and infarct zone regional wall motion at the acute study were strongly associated with improvement of these parameters at 1 week. Resolution of chest pain before acute catheterization, infarct-related artery flow at acute catheterization, and depressed regional wall motion in the noninfarct zone were associated with improvement in both ejection fraction and regional infarct zone function at 1 week. Notably, the time from the onset of symptoms to initiation of thrombolytic treatment was not related to subsequent improvement in ventricular function. Dramatic improvement in left ventricular systolic function is not common after thrombolytic therapy for acute myocardial infarction. Improvement in global and regional systolic function is most closely related to acutely depressed ventricular function and successful acute coronary recanalization. Thus, patients with the most myocardium in jeopardy and successful coronary reperfusion demonstrate the greatest improvement in global and infarct zone ventricular function. Overall, the magnitude of this improvement is modest, suggesting that the benefits of coronary reperfusion are not solely related to improvement in systolic left ventricular function.

Weight excess and insulin resistance mediate the link between obesity and left ventricular dysfunction. We investigated the effect and mechanisms of lifestyle modification on left ventricular function changes in obese patients. Reduction of body weight and insulin resistance was sought using a behavioural intervention programme including dietary restrictions and exercise training in 261 patients (age 45 +/- 13 years) with BMI >or=30 kg/m(2), no history of cardiac disease and a normal stress echocardiogram. Each patient underwent echocardiographic measurement of myocardial deformation and velocity at baseline and at 6 month follow-up. Improvements in left ventricular systolic and diastolic function were demonstrated only in patients with significant reduction of weight and/or insulin resistance. Left ventricular improvement was less frequent in patients with diabetes than in those without (52% vs 82% for strain, 50% vs 81% for strain rate and 59% vs 80% for peak early diastolic myocardial velocity). The independent predictors of improved left ventricular systolic function (increase in strain) were: weight reduction (beta = 0.14, p < 0.05), decrease in the HOMA insulin resistance index (beta = 0.20, p < 0.005) and absence of diabetes (beta = 0.18, p < 0.02). A decrease in HbA(1c) also predicted improvement of left ventricular diastolic function (beta = 0.26, p < 0.001). There was a parallel increment in exercise capacity with intervention and increase in strain was independently correlated with increase in VO(2) (beta = 0.13, p < 0.04). Effective lifestyle modifications in obese patients improve left ventricular systolic and diastolic function, but appear less effective with co-existing diabetes. The reversal of left ventricular function abnormalities is associated with reduction of both weight and insulin resistance, and is accompanied by an increase in cardiorespiratory fitness.

Background: The effect of coronary artery bypass grafting on postoperative left ventricular function is still the subject of ongoing studies. The degree of recovery and its duration have not been precisely determined, and the published data are discordant. The objective of this study was to assess the effect of surgical revascularization on left ventricular systolic function.&#x0D; Methods: We prospectively studied 50 consecutive patients who underwent elective isolated coronary artery bypass grafting in the period from January 2017 to November 2017. All patients had echocardiography preoperatively, pre-discharge, and at 3 and 6 months postoperatively. Left ventricular end-systolic volume, left ventricular end-diastolic volume, stroke volume, and ejection fraction were measured in all patients.&#x0D; Results: The mean age was 57.22±7.04 years. The mean number of grafts was 2.60±1.02. Improvement in Canadian Cardiovascular Society (CCS) score from (2.72 ± 1.03) preoperatively to [(0.12 ± 0.39), p&lt;0.001] after six months was achieved. Additionally, improvement in the patient New York Heart Association (NYHA) score occurred from (1.70 ± 0.97) preoperatively to [(0.12 ± 0.33), p&lt;0.001] after six months. A significant improvement in left ventricular function occurred as demonstrated by improvement in mean left ventricular ejection fraction from (54.14±9.80) % to [(62.40 ± 4.18) %, p&lt;0.001] at six months. The mean total hospital stay was 5.62±1.51 days. The mean total intensive care unit length of stay was 47.16±25.73 hours. Two patients (4%) had re-exploration for bleeding, and postoperative myocardial infarction occurred in three patients (6%). One patient (2%) had postoperative neurocognitive dysfunction, and 3 patients (6%) had postoperative atrial fibrillation. Two patients (4%) suffered from superficial wound infection. There was no hospital mortality. &#x0D; Conclusion: Patients undergoing CABG experienced an improvement in left ventricular contractile function at six months postoperatively. Further studies are required to evaluate the changes after 6 months.

The long-term impact of cardiac resynchronization therapy (CRT)-induced acute improvement in left ventricular (LV) function is largely unknown. The goal of this study was to evaluate the significance of acute improvement in LV function resulting from CRT in patients with chronic heart failure (HF). The authors compared 6-month clinical composite score (CCS) and LV end-systolic (ESV) reduction (≥15% from baseline) response rates of CRT-treated patients enrolled in the Predictors of Response to CRT (PROSPECT) trial who showed an acute increase (≥15% from baseline) in LV ejection fraction (EF) vs those who did not show a similar change in EF. Of the 396 patients who had pre-implant and post-implant EF measurements, 78 (19.7%) had an increase in EF and 318 (80.3%) did not. Acute reduction of mitral regurgitation by at least one grade occurred in 26% and 23% of patients with and without an acute increase in EF, respectively. Patients with an acute increase in EF had significantly lower baseline EF and smaller LV volumes but otherwise similar characteristics. At 6 months, LVEF and LV volumes were significantly higher and lower in the increased EF group, respectively; however, CCS improvement (70.5% vs 69.5%) and LVESV reduction (57.1% vs 54.9%) response rates were comparable in the two groups. An acute ≥15% increase in LVEF with CRT does not predict 6-month effects of CRT on patient outcomes or LV reverse remodeling. That such findings occur in patients with smaller LV volumes, however, may provide additional insight into the mechanisms responsible for CRT-induced long-term improvement in LV function and clinical benefit.

Temporal trends in the use of invasive cardiac procedures for non-ST segment elevation acute coronary syndromes according to initial risk stratification

HomeCirculationVol. 147, No. 4Letter by Li et al Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles” No AccessLetterRequest AccessFull TextAboutView Full TextView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toNo AccessLetterRequest AccessFull TextLetter by Li et al Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles” Qi Li, MD, Zhuqing Li, MD and Chengzhi Lu, PhD Qi LiQi Li School of Medicine, Nankai University, China. Department of Cardiology, Tianjin First Center Hospital, China. Search for more papers by this author , Zhuqing LiZhuqing Li School of Medicine, Nankai University, China. Department of Cardiology, Tianjin First Center Hospital, China. Search for more papers by this author and Chengzhi LuChengzhi Lu https://orcid.org/0000-0002-4546-6395 School of Medicine, Nankai University, China. Department of Cardiology, Tianjin First Center Hospital, China. Search for more papers by this author Originally published23 Jan 2023https://doi.org/10.1161/CIRCULATIONAHA.122.062221Circulation. 2023;147:e66–e67"Letter by Li et al Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles”." Circulation, 147(4), pp. e66–e67FootnotesCirculation is available at www.ahajournals.org/journal/circREFERENCES1. Hosen MR, Goody PR, Zietzer A, Xiang X, Niepmann ST, Sedaghat A, Tiyerili V, Chennupati R, Moore JT, Boon RA, et al. Circulating microRNA-122-5p is associated with a lack of improvement in left ventricular function after transcatheter aortic valve replacement and regulates viability of cardiomyocytes through extracellular vesicles.Circulation. 2022; 146:1836–1854. doi: 10.1161/CIRCULATIONAHA.122.060258LinkGoogle Scholar2. Song J, Zhang Z, Dong Z, Liu X, Liu Y, Li X, Xu Y, Guo Y, Wang N, Zhang M, et al. Microrna-122-5p aggravates angiotensin II-mediated myocardial fibrosis and dysfunction in hypertensive rats by regulating the elabela/apelin-APJ and ACE2-GDF15-porimin signaling.J Cardiovasc Transl Res. 2022; 15:535–547. doi: 10.1007/s12265-022-10214-3CrossrefMedlineGoogle Scholar3. Song J, Tang J, Zhang Z, Liu Y, Zhong J. Targeting the elabela/apelin-apelin receptor axis as a novel therapeutic approach for hypertension.Chin Med J (Engl). 2022; 135:1019–1026. doi: 10.1097/CM9.0000000000001766CrossrefMedlineGoogle Scholar4. Kolte D, Bhardwaj B, Lu M, Alu MC, Passeri JJ, Inglessis I, Vlahakes GJ, Garcia S, Cohen DJ, Lindman BR, et al. Association between early left ventricular ejection fraction improvement after transcatheter aortic valve replacement and 5-year clinical outcomes.JAMA Cardiol. 2022; 7:934–944. doi: 10.1001/jamacardio.2022.2222CrossrefMedlineGoogle Scholar5. Lou J, Wu J, Feng M, Dang X, Wu G, Yang H, Wang Y, Li J, Zhao Y, Shi C, et al. Exercise promotes angiogenesis by enhancing endothelial cell fatty acid utilization via liver-derived extracellular vesicle mir-122-5p.J Sport Health Sci. 2022; 11:495–508. doi: 10.1016/j.jshs.2021.09.009CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails January 24, 2023Vol 147, Issue 4 Advertisement Article InformationMetrics © 2023 American Heart Association, Inc.https://doi.org/10.1161/CIRCULATIONAHA.122.062221PMID: 36689570 Originally publishedJanuary 23, 2023 PDF download Advertisement SubjectsCatheter-Based Coronary and Valvular InterventionsValvular Heart Disease

HomeCirculationVol. 147, No. 4Letter by Halushka and Witwer Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles” No AccessLetterRequest AccessFull TextAboutView Full TextView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toNo AccessLetterRequest AccessFull TextLetter by Halushka and Witwer Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles” Marc K. Halushka and Kenneth W. Witwer Marc K. HalushkaMarc K. Halushka https://orcid.org/0000-0002-7112-7389 Department of Pathology (M.K.H.), The Johns Hopkins University School of Medicine, Baltimore, MD. Search for more papers by this author and Kenneth W. WitwerKenneth W. Witwer Departments of Molecular and Comparative Pathobiology and Neurology (K.W.W.), The Johns Hopkins University School of Medicine, Baltimore, MD. Search for more papers by this author Originally published23 Jan 2023https://doi.org/10.1161/CIRCULATIONAHA.122.061834Circulation. 2023;147:e64–e65"Letter by Halushka and Witwer Regarding Article, “Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles”." Circulation, 147(4), pp. e64–e65FootnotesCirculation is available at www.ahajournals.org/journal/circREFERENCES1. Hosen MR, Goody PR, Zietzer A, Xiang X, Niepmann ST, Sedaghat A, Tiyerili V, Chennupati R, Moore JB, Boon RA, et al. Circulating microRNA-122-5p is associated with a lack of improvement in left ventricular function after transcatheter aortic valve replacement and regulates viability of cardiomyocytes through extracellular vesicles.Circulation. 2022; 146:1836–1854. doi: 10.1161/CIRCULATIONAHA.122.060258LinkGoogle Scholar2. McCall MN, Kim MS, Adil M, Patil AH, Lu Y, Mitchell CJ, Leal-Rojas P, Xu J, Kumar M, Dawson VL, et al. Towards the human cellular microRNAome.Genome Res. 2017; 27:1769–1781. doi: 10.1101/gr.222067.117CrossrefMedlineGoogle Scholar3. Wei Z, Batagov AO, Carter DRF, Krichevsky AM. Fetal bovine serum RNA interferes with the cell culture derived extracellular RNA.Sci Rep. 2016; 6:31175. doi: 10.1038/srep31175CrossrefMedlineGoogle Scholar4. Xanthopoulos A, Starling RC, Kitai T, Triposkiadis F. Heart failure and liver disease: cardiohepatic interactions.JACC Heart Fail. 2019; 7:87–97. doi: 10.1016/j.jchf.2018.10.007CrossrefMedlineGoogle Scholar5. Albanese M, Chen YA, Hüls C, Gärtner K, Tagawa T, Mejias-Perez E, Keppler OT, Göbel C, Zeidler R, Shein M, et al. MicroRNAs are minor constituents of extracellular vesicles that are rarely delivered to target cells.PLoS Genet. 2021; 17:e1009951. doi: 10.1371/journal.pgen.1009951CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails January 24, 2023Vol 147, Issue 4 Advertisement Article InformationMetrics © 2023 American Heart Association, Inc.https://doi.org/10.1161/CIRCULATIONAHA.122.061834PMID: 36689572 Originally publishedJanuary 23, 2023 PDF download Advertisement

Although many patients with multivessel coronary artery disease (CAD) and severely depressed left ventricular (LV) function will benefit from coronary artery bypass graft surgery (CABG), surgeons may be reluctant to perform CABG on these patients without evidence of myocardial viability in regions of severe asynergy. We hypothesized that quantitative planar rest-redistribution 201Tl imaging would identify viable myocardium and predict improved regional and global function after revascularization in patients with depressed LV function and CAD. Twenty-one patients (mean LV ejection fraction, 0.27 +/- 0.05) were studied. Regional and global LV functions were evaluated before and 8 weeks after CABG with radionuclide ventriculography. Segments were prospectively classified as showing normal, mildly reduced, or severely reduced viability on the basis of quantitative analysis of defect severity and redistribution on planar resting 201Tl imaging. By 201Tl criteria, 90% of hypokinetic segments were classified with normal or mildly reduced viability. Among akinetic or dyskinetic segments, 20% had normal 201Tl uptake, 53% had mildly reduced viability, and only 27% had severely reduced viability. 201Tl viability criteria identified segments that improved function after CABG. Sixty-two percent of severely asynergic segments with normal viability and 54% with mildly reduced viability improved function after surgery, but only 23% with severely reduced viability improved function (p = 0.002). When only adequately revascularized segments were considered, the predictive value of a positive preoperative viability scan for functional improvement was 73%. The greatest improvement in global LV function after CABG occurred in patients with the greatest number of asynergic segments classified as viable before surgery (p < 0.01). In 10 patients with more than seven viable, asynergic segments, mean LV ejection fraction increased significantly after CABG (0.29 +/- 0.07 to 0.41 +/- 0.11, p = 0.002). In 11 patients with seven or fewer viable, asynergic segments, mean LV ejection fraction remained unchanged after revascularization (0.27 +/- 0.05 to 0.30 +/- 0.08, p = NS). In patients with CAD and severely depressed LV function, preoperative quantitative planar rest-redistribution. 201Tl imaging identifies viability in many asynergic myocardial segments, and these segments frequently improve function after CABG. The presence of numerous asynergic but viable myocardial segments before surgery correlated significantly with improvement in global LV function after bypass surgery.