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1.
Cardiac (82)Rb PET/CT for fast and non-invasive assessment of microvascular function and structure in asymptomatic patients with type 2 diabetes.
von Scholten, BJ, Hasbak, P, Christensen, TE, Ghotbi, AA, Kjaer, A, Rossing, P, Hansen, TW
Diabetologia. 2016;(2):371-8
Abstract
AIMS/HYPOTHESIS Coronary flow reserve (CFR) and coronary artery calcium (CAC) represent functional and structural aspects of atherosclerosis. We examined the prevalence of reduced CFR and high CAC scores in three predefined groups of participants without known cardiovascular disease: (1) patients with type 2 diabetes and albuminuria; (2) patients with type 2 diabetes and normoalbuminuria; and (3) non-diabetic controls. METHODS In a cross-sectional design, cardiac (82)Rb positron emission tomography/computed tomography was conducted in 60 patients with type 2 diabetes who were free of overt cardiovascular disease and who were stratified by normoalbuminuria (<30 mg/24 h) (n = 30; age [mean ± SD] 60.9 ± 10.1 years) and albuminuria (≥ 30 mg/24 h) (n = 30; age 65.6 ± 4.8 years), and in 30 healthy, non-diabetic controls (age 59.8 ± 9.9 years). RESULTS In controls, normoalbuminuric and albuminuric patients, CFR was 3.0 ± 0.8, 2.6 ± 0.8 and 2.0 ± 0.5, respectively. Reduced CFR (<2.5) was observed in 16.7%, 40.0% and 83.3% of participants, respectively, and median (interquartile range) CAC scores were 0 (0-81), 36 (1-325) and 370 (152-1,025), respectively (p for trend <0.01). After adjustment, the difference in CFR and CAC between albuminuric patients and controls remained significant (p ≤ 0.001). There were trends towards lower CFR and higher CAC scores in normoalbuminuric patients vs controls (p ≤ 0.023) and towards higher CAC scores in albuminuric vs normoalbuminuric patients (p = 0.026). In multivariate regression analysis, a higher urinary albumin excretion rate (UAER) tended to predict reduced CFR in the total population (p = 0.045). When the CAC score was added, there was also a trend (p = 0.032) towards an inverse association with reduced CFR. CONCLUSIONS/INTERPRETATION Type 2 diabetic patients who were free of overt cardiovascular disease had a high prevalence of coronary microvascular dysfunction, especially with concomitant albuminuria, suggesting a common microvascular impairment occurring in multiple microvascular beds. Prospective studies are needed to show the prognostic significance of this finding.
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2.
Acute effects of Finnish sauna and cold-water immersion on haemodynamic variables and autonomic nervous system activity in patients with heart failure.
Radtke, T, Poerschke, D, Wilhelm, M, Trachsel, LD, Tschanz, H, Matter, F, Jauslin, D, Saner, H, Schmid, JP
European journal of preventive cardiology. 2016;(6):593-601
Abstract
BACKGROUND The haemodynamic response to Finnish sauna and subsequent cold-water immersion in heart failure patients is unknown. METHODS Haemodynamic response to two consecutive Finnish sauna (80℃) exposures, followed by a final head-out cold-water immersion (12℃) was measured in 37 male participants: chronic heart failure (n = 12, 61.8 ± 9.2 years), coronary artery disease (n = 13, 61.2 ± 10.6 years) and control subjects (n = 12, 60.9 ± 8.9 years). Cardiac output was measured non-invasively with an inert gas rebreathing method prior to and immediately after the first sauna exposure and after cold-water immersion, respectively. Blood pressure was measured before, twice during and after sauna. The autonomic nervous system was assessed by power spectral analysis of heart rate variability. Total power, low-frequency and high-frequency components were evaluated. The low frequency/high frequency ratio was used as a marker of sympathovagal balance. Sauna and cold-water immersion were well tolerated by all subjects. RESULTS Cardiac output and heart rate significantly increased in all groups after sauna and cold-water immersion (p < 0.05), except for coronary artery disease patients after sauna exposure. Systolic blood pressure during sauna decreased significantly in all groups with a nadir after 6 min (all p < 0.05). Cold-water immersion significantly increased systolic blood pressure in all groups (p < 0.05). No change in the low/high frequency ratio was found in chronic heart failure patients. In coronary artery disease patients and controls a prolonged increase in low frequency/high frequency ratio was observed after the first sauna exposure. CONCLUSIONS Acute exposure to Finnish sauna and cold-water immersion causes haemodynamic alterations in chronic heart failure patients similarly to control subjects and in particular did not provoke an excessive increase in adrenergic activity or complex arrhythmias.
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3.
Levothyroxine improves abnormal cardiac bioenergetics in subclinical hypothyroidism: a cardiac magnetic resonance spectroscopic study.
Madathil, A, Hollingsworth, KG, Blamire, AM, Razvi, S, Newton, JL, Taylor, R, Weaver, JU
The Journal of clinical endocrinology and metabolism. 2015;(4):E607-10
Abstract
CONTEXT It is well established that subclinical hypothyroidism (SCH) is associated with mild cardiac dysfunction, but it is unknown whether there is an underlying impairment of cardiac bioenergetic function. OBJECTIVE The objective of the study was to quantify the cardiac phosphocreatine to adenosine triphosphate ratio (PCr to ATP) in SCH, compared with healthy controls, and to measure the effect of 6 months of levothyroxine treatment. DESIGN AND SETTING This was a 6-month, prospective, case-controlled interventional study. PARTICIPANTS AND MAIN OUTCOME MEASURES The PCr to ATP ratio was measured using phosphorus-31 magnetic resonance spectroscopy in subjects with SCH at baseline and after levothyroxine therapy (1.6 μg/kg · d) and compared with age- and gender-matched euthyroid controls. All subjects were free of overt heart disease. RESULTS Twenty-one subjects with SCH (normal free T4 and serum TSH between 4.1 and 10 mIU/L) and 17 controls were matched for age (mean age 40.5 vs 43.3 y) and sex (females 81% vs 82%) but differed in mean TSH (6.5 vs 2.1 mIU/L, P < .001). At baseline the mean (± SD) PCr to ATP ratio in SCH was lower than in controls (1.80 ± 0.26 vs 2.07 ± 0.20, P = .001). In the 16 subjects studied after levothyroxine treatment, the PCr to ATP ratio improved (from 1.74 ± 0.24 to 1.91 ± 0.26, P = .004) and approached controls (borderline loss of significance, P = .051). On multivariate analysis, SCH was independently associated with a reduced PCr to ATP ratio, even after adjusting for confounding variables (body mass index and fasting glucose) (P = .001). CONCLUSION Our results demonstrate early cardiac bioenergetic impairment in SCH, which is reversible with levothyroxine therapy. This mechanistic insight provides justification for longitudinal trials to determine whether improvement in bioenergetic function improves cardiovascular outcome.
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4.
Muscle strength, motor performance, cardiac and muscle biomarkers in detection of muscle side effects during and after acute lymphoblastic leukemia treatment in children.
Akyay, A, Olcay, L, Sezer, N, Atay Sönmez, Ç
Journal of pediatric hematology/oncology. 2014;(8):594-8
Abstract
Muscle side effects have not been frequently assessed in childhood acute lymphoblastic leukemia (ALL) patients. Our objective was to determine the early and late muscle side effects during childhood ALL treatment. To this end, we examined the early muscle side effects in 15 newly diagnosed "therapy patients" (group I), and the late side effects in 18 ALL survivors "off therapy patients" (group II). Muscle side effects were assessed by measuring hand grip strength (HGS), the "timed up and go" (TUG) test, creatine phosphokinase, myoglobin, plasma electrolytes, cardiac troponin I before and after induction chemotherapy in group I. The same parameters and cranial radiotherapy dose were examined in group II at a single timepoint. Cumulative doses of chemotherapy were calculated, and echocardiograms were obtained for each group. As a result, we found that the HGS and TUG measures of group I at the end of induction were poorer than measures of the first admission, control subjects, and group II. Low HGS measures had been normalized over time, but the TUG measures remained poor. Overt rhabdomyolysis and pyomyositis were not detected in any of the patients. These results suggested that muscle side effect monitoring might be helpful in the follow-up of children with ALL.
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5.
Comparison of severity of obstructive sleep apnea and degree of accumulation of cardiac 123I-MIBG radioactivity as a diagnostic marker for idiopathic REM sleep behavior disorder.
Miyamoto, T, Miyamoto, M, Suzuki, K, Ikematsu, A, Usui, Y, Inoue, Y, Hirata, K
Sleep medicine. 2009;(5):577-80
Abstract
OBJECTIVE We investigated cardiac (123)I-metaiodobenzylguanidine (MIBG) scintigraphic assessment as a supportive diagnostic indicator for idiopathic REM sleep behavior disorder (RBD) complicated by moderate to severe obstructive sleep apnea (OSA). METHODS (123)I-MIBG was intravenously injected in 23 idiopathic RBD patients with AHI < 5/h, 9 idiopathic RBD patients with 5 or= 15/h, and 16 moderate to severe obstructive sleep apnea syndrome (OSAS) patients without RBD by polysomnography. RESULTS Cardiac MIBG uptake based on H/M was significantly decreased in RBD patients with or without OSA compared with patients with moderate to severe OSAS without RBD. ROC analysis revealed that a delayed H/M cut-off value of 1.97 was useful for differentiating idiopathic RBD complicated by moderate to severe OSA from moderate to severe OSAS without RBD. CONCLUSIONS (123)I-MIBG cardiac scintigraphy has the potential to distinguish true RBD from pseudo-RBD associated with OSA. These results are noteworthy because treatment options and follow-up protocols are determined based on evaluation of moderate to severe OSA complicated with RBD, such as overlapping primary sleep disorders.
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6.
Suppression of myocardial 18F-FDG uptake by preparing patients with a high-fat, low-carbohydrate diet.
Williams, G, Kolodny, GM
AJR. American journal of roentgenology. 2008;(2):W151-6
Abstract
OBJECTIVE Myocardial 18F-FDG uptake in PET scans in patients prepared by the usual fasting protocol may result in difficulties in interpretation because variable uptake may yield false-positive results regarding mediastinal abnormalities. We aimed to analyze, retrospectively, the effect of diet on myocardial FDG uptake. MATERIALS AND METHODS The "fasting" group comprised 101 consecutive patients before a clinical change in the patient preparation protocol. The "new diet" group comprised 60 consecutive patients after the clinical protocol change who were directed to consume a very high-fat, low-carbohydrate, protein-permitted (VHFLCPP) diet before FDG injection. All patients were given a questionnaire that was used to verify diet adherence. Nonadherers or patients failing to complete questionnaires were excluded from analysis. Myocardial uptake was evaluated by measuring the maximum standardized uptake value (SUVmax) in areas defined by CT as being cardiac. RESULTS The average SUVmax for the fasting group (n = 101) was 8.8 +/- 5.7, and the average SUVmax for the VHFLCPP group (n = 60) was 3.9 +/- 3.6. The one-tailed Student's t test yielded a p value of < 0.00001. CONCLUSION A VHFLCPP meal eaten 3-6 hours before FDG injection suppresses myocardial FDG uptake. This should facilitate definition of mediastinal abnormalities on FDG PET, particularly with stand-alone PET. Furthermore, this patient preparation protocol may permit the detection of biologically active coronary artery disease.
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7.
[Intraoperative myocardial protection with extracellular cardioplegic solutions in patients with cardiac valve diseases].
Zhidkov, IL, Ivanov, VA, Kozhevnikov, VA, Charnaia, MA, Mukhamedzianova, AR, Trekova, NA
Anesteziologiia i reanimatologiia. 2007;(2):38-42
Abstract
A hundred patients operated on under extracorporeal circulation (EC) with bicaval cannulation in the moderate general hypothermia mode were intraoperatively examined. According to the used cardioplegic solution, all the patients were divided into three groups: 1) Konsol; 2) Konsol MF; 3) St. Thomas (a control group). All the groups were matched by age, gender, the duration of myocardial ischemia (MI) (37-128 min), that of EC (52-186 min), and the nature of surgical interventions, of which mitral valve replacement amounted to 72-78%. To prepare a modified solution, 20 ml of 40% glucose, 20 units of insulin, and 200 mg of creatine phosphate (Neoton) were added to a flask containing 400 ml of Konsol. The efficiency of myocardial protection was evaluated by the data characterizing cardiac arrest and cardiac performance resumption, as well as by heart rate and the use of inotropic support in the reperfusion period. The parameters of central hemodynamics and systemic coronary blood flow, the concentrations of glucose and lactate, the blood gas and electrolyte composition of the coronary sinus (CS), myocardial oxygen consumption and the oxygen-utilizing coefficient were monitored. The cardioplegic solutions Consol and Consol MF were found to have a more effective cardioprotective activity in patients with cardiac valvular disease, operated on under EC and moderate hypothermia that St. Thomas'solution. Modification of the Consol solution by adding glucose, creatine phosphate, and insulin improves the protective effect of the solution, promoting a rapider transition of the myocardium from anaerobic to aerobic metabolism.
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8.
Cardiorespiratory effects of warm water immersion in elderly patients with chronic heart failure.
Cider, A, Sunnerhagen, KS, Schaufelberger, M, Andersson, B
Clinical physiology and functional imaging. 2005;(6):313-7
Abstract
BACKGROUND Hydrotherapy might be included in the rehabilitation of patients with chronic heart failure (CHF), but little is known about the acute cardiorespiratory reaction in warm water. The aim of this study was to assess the acute cardiorespiratory effect of immersion in warm water, in a clinical setting, in elderly patients with CHF compared with healthy age and sex matched persons. METHODS Twelve patients (three females) with CHF, NYHA II-III, age 64 +/- 6 years, and 12 healthy subjects were studied. Cardiorespiratory changes, on land and in a temperature-controlled swimming pool (33-34 degrees C) were assessed during rest and exercise, in a sitting position, using continuous gas analyses. RESULTS There were no significant differences, land versus water, in carbon dioxide production, total ventilation, respiratory frequency, respiratory exchange ratio, heart rate or blood pressure in either of the groups. A significant difference was found in oxygen uptake, at rest, land versus water in patients with CHF in comparison with healthy subjects (-0.2 +/- 0.4 versus +0.3 +/- 0.6 ml kg(-1) min(-1), P < 0.01). Oxygen kinetics (tau) increased significantly (P = 0.01) in both groups during exercise in water. CONCLUSION Hydrotherapy was well tolerated and the vast majority of the cardiorespiratory responses, during warm water immersion in a clinical setting, are similar in patients with CHF compared with healthy subjects. However, further larger studies, are needed to better understand the physiological reactions during hydrotherapy.
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9.
Relation of regional sympathetic denervation and myocardial perfusion disturbance to wall motion impairment in Chagas' cardiomyopathy.
Simões, MV, Pintya, AO, Bromberg-Marin, G, Sarabanda, AV, Antloga, CM, Pazin-Filho, A, Maciel, BC, Marin-Neto, JA
The American journal of cardiology. 2000;(9):975-81
Abstract
Impairment of sinus node autonomic control and myocardial perfusion disturbances have been described in patients with chronic Chagas' cardiomyopathy. However, it is not clear how these conditions contribute to myocardial damage. In this investigation, iodine-123 (I-123) meta-iodobenzylguanidine (MIBG) and thallium-201 myocardium segmental uptake were studied in correlation with the severity of left ventricular (LV) dysfunction detected in various phases of Chagas' heart disease. Group I consisted of 12 subjects (43 +/- 4 years, 7 men) with no symptoms and no cardiac involvement on electrocardiogram (ECG) or echocardiography; group II consisted of 13 patients (48 +/- 3 years, 9 men) with abnormal resting ECG and/or echocardiographic segmental abnormalities, and LV ejection fraction of > or = 0.5; group III was comprised of 12 patients (59 +/- 3 years, 10 men) with more severe heart disease, LV dilation, and LV ejection fraction of < 0.5. Eighteen control volunteers (38 +/- 3 years, 9 men) were also included in the study. I-123 MIBG single-photon emission computed tomographic (SPECT) segmental uptake defects were observed in group I (33%), group II (77%), and group III (92%). Quantitative analysis showed mean areas of reduced LV I-123-MIBG uptake: group I was 3.7 +/- 2.1%; group II was 8.3 +/- 2.3%; and group III was 19.0 +/- 3.3%. The differences between group I and both groups II and III were statistically significant (p < 0.001, analysis of variance test). Myocardial perfusion defects (reversible, fixed, and paradox) were observed in group I (83%), group II (69%), and group III (83%). A marked topographic association between perfusion, innervation, and wall motion abnormalities (assessed by gated-SPECT perfusion studies) was observed in all the groups. Defects predominated in the inferior, posterior lateral, and apical LV regions. Thus, extensive impairment of cardiac sympathetic function at the ventricular level occured early in the course of Chagas' cardiomyopathy and was related to regional myocardial perfusion disturbances, before wall motion abnormalities. Both conditions are associated with progression of ventricular dysfunction.