Resistance Exercise Restores Endothelial Function and Reduces Blood Pressure in Type 1 Diabetic Rats

Background: Resistance exercise effects on cardiovascular parameters are not consistent. Objectives: The effects of resistance exercise on changes in blood glucose, blood pressure and vascular reactivity were evaluated in diabetic rats. Methods: Wistar rats were divided into three groups: control group (n = 8); sedentary diabetic (n = 8); and trained diabetic (n = 8). Resistance exercise was carried out in a squat device for rats and consisted of three sets of ten repetitions with an intensity of 50%, three times per week, for eight weeks. Changes in vascular reactivity were evaluated in superior mesenteric artery rings. Results: A significant reduction in the maximum response of acetylcholine-induced relaxation was observed in the sedentary diabetic group (78.1 ± 2%) and an increase in the trained diabetic group (95 ± 3%) without changing potency. In the presence of NG-nitro-L-arginine methyl ester, the acetylcholine-induced relaxation was significantly reduced in the control and trained diabetic groups, but not in the sedentary diabetic group. Furthermore, a significant increase (p < 0.05) in mean arterial blood pressure was observed in the sedentary diabetic group (104.9 ± 5 to 126.7 ± 5 mmHg) as compared to that in the control group. However, the trained diabetic group showed a significant decrease (p < 0.05) in the mean arterial blood pressure levels (126.7 ± 5 to 105.1 ± 4 mmHg) as compared to the sedentary diabetic group. Conclusions: Resistance exercise could restore endothelial function and prevent an increase in arterial blood pressure in type 1 diabetic rats.

Autologous Transplantation of Bone Marrow Adult Stem Cells for the Treatment of Idiopathic Dilated Cardiomyopathy

Background:Morbimortality in patients with dilated idiopathic cardiomyopathy is high, even under optimal medical treatment. Autologous infusion of bone marrow adult stem cells has shown promising preliminary results in these patients.Objective:Determine the effectiveness of autologous transplantation of bone marrow adult stem cells on systolic and diastolic left ventricular function, and on the degree of mitral regurgitation in patients with dilated idiopathic cardiomyopathy in functional classes NYHA II and III.Methods:We administered 4,54 x 108 ± 0,89 x 108 bone marrow adult stem cells into the coronary arteries of 24 patients with dilated idiopathic cardiomyopathy in functional classes NYHA II and III. Changes in functional class, systolic and diastolic left ventricular function and degree of mitral regurgitation were assessed after 3 months, 6 months and 1 year.Results:During follow-up, six patients (25%) improved functional class and eight (33.3%) kept stable. Left ventricular ejection fraction improved 8.9%, 9.7% e 13.6%, after 3, 6 and 12 months (p = 0.024; 0.017 and 0.018), respectively. There were no significant changes neither in diastolic left ventricular function nor in mitral regurgitation degree. A combined cardiac resynchronization and implantable cardioversion defibrillation was implanted in two patients (8.3%). Four patients (16.6%) had sudden death and four patients died due to terminal cardiac failure. Average survival of these eight patients was 2.6 years.Conclusion:Intracoronary infusion of bone marrow adult stem cells was associated with an improvement or stabilization of functional class and an improvement in left ventricular ejection fraction, suggesting the efficacy of this intervention. There were no significant changes neither in left ventricular diastolic function nor in the degree of mitral regurgitation.

Development of Anatomophysiologic Knowledge Regarding the Cardiovascular System: From Egyptians to Harvey

Our knowledge regarding the anatomophysiology of the cardiovascular system (CVS) has progressed since the fourth millennium BC. In Egypt (3500 BC), it was believed that a set of channels are interconnected to the heart, transporting air, urine, air, blood, and the soul. One thousand years later, the heart was established as the center of the CVS by the Hippocratic Corpus in the medical school of Kos, and some of the CVS anatomical characteristics were defined. The CVS was known to transport blood via the right ventricle through veins and the pneuma via the left ventricle through arteries. Two hundred years later, in Alexandria, following the development of human anatomical dissection, Herophilus discovered that arteries were 6 times thicker than veins, and Erasistratus described the semilunar valves, emphasizing that arteries were filled with blood when ventricles were empty. Further, 200 years later, Galen demonstrated that arteries contained blood and not air. With the decline of the Roman Empire, Greco-Roman medical knowledge about the CVS was preserved in Persia, and later in Islam where, Ibn Nafis inaccurately described pulmonary circulation. The resurgence of dissection of the human body in Europe in the 14th century was associated with the revival of the knowledge pertaining to the CVS. The main findings were the description of pulmonary circulation by Servetus, the anatomical discoveries of Vesalius, the demonstration of pulmonary circulation by Colombo, and the discovery of valves in veins by Fabricius. Following these developments, Harvey described blood circulation.

Palliative Senning in the Treatment of Congenital Heart Disease with Severe Pulmonary Hypertension

Background:Transposition of the great arteries (TGA) is the most common cyanotic cardiopathy, with an incidence ranging between 0.2 and 0.4 per 1000 live births. Many patients not treated in the first few months of life may progress with severe pulmonary vascular disease. Treatment of these patients may include palliative surgery to redirect the flow at the atrial level.Objective:Report our institutional experience with the palliative Senning procedure in children diagnosed with TGA and double outlet right ventricle with severe pulmonary vascular disease, and to evaluate the early and late clinical progression of the palliative Senning procedure.Methods:Retrospective study based on the evaluation of medical records in the period of 1991 to 2014. Only patients without an indication for definitive surgical treatment of the cardiopathy due to elevated pulmonary pressure were included.Results:After one year of follow-up there was a mean increase in arterial oxygen saturation from 62.1% to 92.5% and a mean decrease in hematocrit from 49.4% to 36.3%. Lung histological analysis was feasible in 16 patients. In 8 patients, pulmonary biopsy grades 3 and 4 were evidenced.Conclusion:The palliative Senning procedure improved arterial oxygen saturation, reduced polycythemia, and provided a better quality of life for patients with TGA with ventricular septal defect, severe pulmonary hypertension, and poor prognosis.

Anxiety, Depression, and General Psychological Distress in Patients with Coronary Slow Flow

AbstractBackground:The relationship between psychiatric illness and heart disease has been frequently discussed in the literature. The aim of the present study was to investigate the relationship between anxiety, depression and overall psychological distress, and coronary slow flow (CSF).Methods:In total, 44 patients with CSF and a control group of 50 patients with normal coronary arteries (NCA) were prospectively recruited. Clinical data, admission laboratory parameters, and echocardiographic and angiographic characteristics were recorded. Symptom Checklist 90 Revised (SCL-90-R), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI) scales were administered to each patient.Results:The groups were comparable with respect to age, sex, and atherosclerotic risk factors. In the CSF group, BAI score, BDI score, and general symptom index were significantly higher than controls (13 [18.7] vs. 7.5 [7], p = 0.01; 11 [14.7] vs. 6.5 [7], p = 0.01; 1.76 [0.81] vs. 1.1[0.24], p = 0.01; respectively). Patients with CSF in more than one vessel had the highest test scores. In univariate correlation analysis, mean thrombolysis in myocardial infarction (TIMI) frame counts were positively correlated with BAI (r = 0.56, p = 0.01), BDI (r = 0.47, p = 0.01), and general symptom index (r = 0.65, p = 0.01). The psychiatric tests were not correlated with risk factors for atherosclerosis.Conclusion:Our study revealed higher rates of depression, anxiety, and overall psychological distress in patients with CSF. This conclusion warrants further studies.

Genetic and Environmental Effects on the Abdominal Aortic Diameter Development

Abstract Background: Configuration of the abdominal aorta is related to healthy aging and a variety of disorders. Objectives: We aimed to assess heritable and environmental effects on the abdominal aortic diameter. Methods: 114 adult (69 monozygotic, 45 same-sex dizygotic) twin pairs (mean age 43.6 ± 16.3 years) underwent abdominal ultrasound with Esaote MyLab 70X ultrasound machine to visualize the abdominal aorta below the level of the origin of the renal arteries and 1-3 cm above the bifurcation. Results: Age- and sex-adjusted heritability of the abdominal aortic diameter below the level of the origin of the renal arteries was 40% [95% confidence interval (CI), 14 to 67%] and 55% above the aortic bifurcation (95% CI, 45 to 70%). None of the aortic diameters showed common environmental effects, but unshared environmental effects were responsible for 60% and 45% of the traits, respectively. Conclusions: Our analysis documents the moderate heritability and its segment-specific difference of the abdominal aortic diameter. The moderate part of variance was explained by unshared environmental components, emphasizing the importance of lifestyle factors in primary prevention. Further studies in this field may guide future gene-mapping efforts and investigate specific lifestyle factors to prevent abdominal aortic dilatation and its complications.

The Labdane Ent-3-Acetoxy-Labda-8(17), 13-Dien-15-Oic Decreases Blood Pressure In Hypertensive Rats

Abstract Background: Labdane-type diterpenes induce lower blood pressure via relaxation of vascular smooth muscle; however, there are no studies describing the effects of labdanes in hypertensive rats. Objective: The present study was designed to investigate the cardiovascular actions of the labdane-type diterpene ent-3-acetoxy-labda-8(17), 13-dien-15-oic acid (labda-15-oic acid) in two-kidney 1 clip (2K-1C) renal hypertension. Methods: Vascular reactivity experiments were performed in aortic rings isolated from 2K-1C and normotensive (2K) male Wistar rats. Nitrate/nitrite (NOx) measurement was performed in aortas by colorimetric assay. Blood pressure measurements were performed in conscious rats. Results: Labda-15-oic acid (0.1-300 µmol/l) and forskolin (0.1 nmol/l - 1 µmol/l) relaxed endothelium-intact and endothelium-denuded aortas from both 2K-1C and 2K rats. Labda-15-oic acid was more effective at inducing relaxation in endothelium-intact aortas from 2K pre-contracted with phenylephrine when compared to the endothelium-denuded ones. Forskolin was more potent than labda-15-oic acid at inducing vascular relaxation in arteries from both 2K and 2K-1C rats. Labda-15-oic acid-induced increase in NOx levels was lower in arteries from 2K-1C rats when compared to 2K rats. Intravenous administration of labda-15-oic acid (0.3-3 mg/kg) or forskolin (0.1-1 mg/kg) induced hypotension in conscious 2K-1C and 2K rats. Conclusion: The present findings show that labda-15-oic acid induces vascular relaxation and hypotension in hypertensive rats.

Development of an in vitro model for studying aneurysms

The aims of this project was to develop an arterial aneurysm using either enzymatic or laser degradation of the arterial wall without affecting the viability of the tissue and to cultivate the arteries under pulsatile flow conditions in a vascular bioreactor with a view to investigate the progress of the disease. Characteristics of aneurysms are the degradation of smooth muscle cells, collagen and elastin. Detached smooth muscle cells and degradation of the collagen matrix and elastin fibres were observed in arteries degraded with enzymes elastase and collagenase. Only remnants of the arterial wall were detected after cultivation. This might be a suitable model for late stage aneurysms. Arteries treated with the laser system showed no charring or heat damage of the not dissected area. Collagen matrix, smooth muscle cells and elastin fibres were intact. A clear defined cut was made in a depth of 200 μm and tissue was removed. Following cultivation of these arteries a dilation of the laser-eroded area was observed. This model can mimic atherosclerotic aneurysms, when plaques weaken the tunica media of the blood vessel wall and rupture. Limitations of this study were contamination of the bioreactor system and a low number of cultivations. The aim to generate a living arterial aneurysm in vitro was not achieved. Tissue viability decreased to the level of negative controls after cultivation.

Estudos sobre thrombose cardiaca e endocardite parietal de origem não valvular

1.-Since the parietal endocarditis represents a chapter generally neglected, owing to the relative lack of cases, and somewhat confused because there various terms have been applied to a very same morbid condition, it justifies the work which previously we tried to accomplish, of nosographic classification. Taking into account the functional disturbances and the anatomical changes, all cases of parietal endocarditis referred to in the litterature were distributed by the following groups: A-Group-Valvulo-parietal endocarditis. 1st . type-Valvulo-parietal endocarditis per continuum. 2nd. type-Metastatic valvulo-parietal endocarditis. 3rd. type-Valvulo-parietal endocarditis of the mitral stenosis. B-Group-Genuine parietal endocarditis. a) with primary lesions in the myocardium. b) with primary lesions in the endocardium. 4th type-Fibrous chronic parietal endocarditis (B A Ü M L E R), « endocarditis parietalis simplex». 5th type-Septic acute parietal endocarditis (LESCHKE), «endocarditis parietalis septica». 6th type-Subacute parietal endocarditis (MAGARINOS TORRES), «endocarditis muralis lenta». 2.-Studying a group of 14 cases of fibrous endomyocarditis with formation of thrombi, and carrying together pathological and bacteriological examinations it has been found that some of such cases represent an infectious parietal endocarditis, sometimes post-puerperal, of subacute or slow course, the endocardic vegetations being contamined by pathogenic microörganisms of which the most frequent is the Diplococcus pneumoniae, in most cases of attenuated virulence. Along with the infectious parietal endocarditis, there occur arterial and venous thromboses (abdominal aorta, common illiac and femural arteries and external jugular veins). The case 5,120 is a typical one of this condition which we name subacute parietal endocarditis (endocarditis parietalis s. muralis lenta). 3.-The endocarditis muralis lenta encloses an affection reputed to be of rare occurrence, the «myocardite subaigüe primitive», of which JOSSERAND and GALLAVARDIN published in 1901 the first cases, and ROQUE and LEVY, another, in 1914. The «myocardite subaigüe primitive» was, wrongly, in our opinion, included by WALZER in the syndrome of myocardia of LAUBRY and WALZER, considering that, in the refered cases of JOSSERAND and GALLAVARDIN and in that of ROQUE and LEVY, there are described rather considerable inflammatory changes in the myocardium and endocardium. The designation «myocardia» was however especially created by LAUBRY and WALZER for the cases of heart failure in which the most careful aetiologic inquiries and the most minucious clinical examination were unable to explain, and in which, yet, the post-mortem examination did not reveal any anatomical change at all, it being forcible to admit, then, a primary functional change of the cardiac muscle fibre. This special cardiac condition is thoroughly exemplified in the observation that WALZER reproduces on pages 1 to 7 of his book. 4.-The clinical picture of the subacute parietal endocarditis is that of heart failure with oedemas, effusion in the serous cavities and passive chronic congestion of the lungs, liver, kideys and spleen associated, to that of an infectious disease of subacute course. The fever is rather transient oscillating around 99.5 F., being intersected with apyretic periods of irregular duration; it is not dependent on any evident extracardiac septic infection. In other cases the fever is slight, particularly in the final stage of the disease, when the heart failure is well established. The rule is to observe then, hypothermy. The cardiac-vascular signs consist of enlargement of the cardiac dullness, smoothing of the cardiac sounds, absence of organic murmurs and accentuated and persistent tachycardia up to a certain point independent of fever. The galloprhythm is present, in most cases. The signs of the pulmonary infarct are rather expressed by the aspect of the sputum, which is foamy and blood-streaked than by the classic signs. Cerebral embolism was a terminal accident on various cases. Yet, in some of them, along with the signs of septicemia and of cardiac insufficiency, occurred vascular, arterial (abdominal aorta, common illiac and femurals arteries) and venous (extern jugular veins) thromboses. 5. The autopsy revealed an inflammatory process located on the parietal endocardium, accompanied by abundant formation of ancient and recent thrombi, being the apex of the left ventricle, the junction of the anterior wall of the same ventricle, with the interventricular septum, and the right auricular appendage, the usual seats of the inflammatory changes. The region of the left branch of HIS’ bundle is spared. The other changes found consist of fibrosis of the myocardium (healed infarcts and circumscribed interstitial myocarditis), of recent visceral infarcts chiefly in lungs, spleen and brain, of recent or old infarcts in the kidneys (embolic nephrocirrhosis) and in the spleen, and of vascular thromboses (abdominal aorta, common illiacs and femurals arteries and external jugular veins), aside from hydrothorax, hydroperitoneum, cutaneous oedema, chronic passive congestion of the liver, lungs, spleen and kidneys and slight ictericia. 6. In the subacute parietal endocarditis the primary lesions sometimes locate themselves at the myocardium, depending on the ischemic necrosis associated to the arteriosclerosis of the coronariae arteries, or on an specific myocarditis. Other times, the absence of these conditions is suggestive of a primary attack to the parietal endocardium which is then the primary seat of the lesions. It matters little whatever may be the initial pathogenic mechanism; once injured the parietal endocardium and there being settled the infectious injury, the endocarditis develops with peculiar clinical and anatomical characters of remarkable uniformity, constituting an anatomo-clinical syndrome. 7.-The histologic sections show that recent lesions…

Miocardite no macaco Cebus após inoculações repetidas com Schizotrypanum cruzi

Transmission of Chagas disease is realized through contamination of ocular conjunctiva, mucosa or skin with infected dejections eliminated by the insect vectors of Schizotrypanum cruzi (Triatoma infestans, Panstrongylus megistus and Rhodnius prolixus). The triatomid bugs live in holes and craks in the walls, in beds, behind trunks, etc. Found in primitive mud huts covered with thatched roofs, and so the human dwellers have many chances to contract the disease, reinfections being reasonably more to expect than a single inoculation. Experimental work reproducing those natural conditions is welcomed as some important features in the pathologic picture of the disease such as the extensive myocardial fibrosis seen in chronic cases are still incompletely known. Microscopic changes were studied in the heart muscle of seven Cebus monkeys infected by S. cruzi. This animal survives the acute stage of the disease and so is particularly suited to experiments of long duration in which several inoculations of S. cruzi are performed. Three different strains of S. cruzi isolated from acute cases of Chagas' disease were employed. One monkey was injected in the skin with infected blood and necropsied after 252 days. Two monkeys were three times, and one, eight times infected in skin, one of them with contaminated blood, and two with contaminated blood and dejections from infected bugs. The necropsies were performed after 35, 95 and 149 days. One monkey was three times inoculated through the intact ocular conjunctiva (one time with infected blood, two times with dejections from infected bugs), and one time through the wounded buccal mucosa, and necropsied after 134 days. Another monkey was six times inoculated, four times through the intact ocular conjunctiva (one time with contaminated blood, three times with dejections from infected bugs) and two times injected in the skin with infected blood, and necropsied after 157 days. Finally, another monkey was nine times inoculated, four times through the intact ocular conjunctiva (one time with infected blood, and three times with dejections from infected bugs), and five times injected in the skin (four times with contaminated blood, and one time with dejections from infected bugs), and necropsied after 233 days. The microscopic picture was uniform presenting, however, considerable individual variations, and was represented by diffuse interstitial myocarditis, frequently more (marked in the right ventricle base of the heart), accompanied by lymphatic stasis. The infiltration consists of macrophages, plasma cells and lymphocytes, the cellular reaction having sometimes a perivascular distribution, involving the auriculo-ventricular system of conduction, endocardium, epicardium and cardiac sympathetic gangliae. The loss of cardiac muscle fibers was always minimal. Leishmanial forms of S. cruzi in myocardial fibers are scanty and, in two cases, absent. Fatty necrosis in the epicardium was noted in two cases. Obliterative changes of medium-sized branches of coronary arteries (hypersensitivity reaction?) and multiple infarcts of the myocardium was found in one instance. The diffuse myocarditis induced by S. cruzi in several species of monkeys of the genus Cebus observed after 233 days (several inoculations) and 252 days (single inoculation) is not associated with disseminated fibrosis such as is reported in chronic cases of Chagas' disease. Definite capacity of reversion is another characteristic of the interstitial myocarditis observed in the series of Cebus monkeys here studied. The impression was gained that repeated inoculation with S. cruzi may influence the myocardial changes differently according to the period between the reinoculations. A short period after the first inoculation is followed by more marked changes, while long periods are accompanied by slight changes, which suggests an active immunisation produced by the first inoculation. More data are required, however before a definite statement is made on this subject considering that individual variations, the natural capacity of reversion of the interstitial myocarditis and the employement of more than a species of Cebus monkeys probably exerts influence also in the results here reported.

The interaction of Gram negative bacteria and S. mansoni in mice with experimental Schistosomiasis

Animals (122 mice) were infected each with eighty cercariae of S. mansoni and subsequently challenged intravenously eight weeks later with the following gram-negative organisms. S. typhi, E. coli, Klebsiella-enterobacter species, Proteus mirabilis and Pseudomonas aeruginosa. Enumeration of bacteria in the liver, spleen and blood and S. mansoni from the portal sistem was performed from one to four weeks later in infected animals. A significant difference between infection produced by S. typhi and other gram negative organisms was observed: S. typhi persisted longer in the spleen and liver and could be recovered from S. mansoni worms up to three weeks following bacterial infection. Other gram negative bacteria disappeared from S. mansoni worms after two weeks of initial challenge. Additional animals (51 mice) infected with S. mansoni were given S. typhi, E. coli or sterile saline. After two weeks, animals were sacrificed and the recovery rate of worms from the portal system, and the mesenteric and hepatic oogram were determined. in animals infected with E. coli a significant decrease in the number of worms was observed compared to the saline control group; thirty worms were recovered in the control group compared to two worms in e. coli infected animals. In addition, the patterns of oviposition was significantly different in these latter animals suggesting complete inhibition of this process. Following S. typhi infection the difference in recovery of worms and pattern of oviposition was minimal. These findings suggest a difference in the interaction of various gram negative bacteria and S. mansoni and are consistent with the clinical observation of prolonged salmonella bacteremia in patients with schistosomiasis.

Extracorporeal membrane oxygenation support after heart explantation: a proposal on how to deal with hyperacute rejection of heart transplant

Purpose: In extreme situations, such as hyperacute rejection of heart transplant or major bleeding per-operating complications, an urgent heart explantation might be the only means of survival. The aim of this experimental study was to improve the surgical technique and the hemodynamics of an Extracorporeal Membrane Oxygenation (ECMO) support through a peripheral vascular access in an acardia model. Methods: An ECMO support was established in 7 bovine experiments (59±6.1 kg) by the transjugular insertion to the caval axis of a self-expanded cannula, with return through a carotid artery. After baseline measurements of pump flow and arterial and central venous pressure, ventricular fibrillation was induced (B), the great arteries were clamped, the heart was excised and right and left atria remnants, containing the pulmonary veins, were sutured together leaving an atrial septal defect (ASD) over the cannula in the caval axis. Measurements were taken with the pulmonary artery (PA) clamped (C) and anastomosed with the caval axis (D). Regular arterial and central venous blood gases tests were performed. The ANOVA test for repeated measures was used to test the null hypothesis and a Bonferroni t method for assessing the significance in the between groups pairwise comparison of mean pump flow. Results: Initial pump flow (A) was 4.3±0.6 L/min dropping to 2.8±0.7 L/min (P B-A= 0.003) 10 minutes after induction of ventricular fibrillation (B). After cardiectomy, with the pulmonary artery clamped (C) it augmented not significantly to 3.5±0.8 L/min (P C-B= 0.33, P C-A= 0.029). Finally, PA anastomosis to the caval axis was followed by an almost to baseline pump flow augmentation (4.1±0.7 L/min, P D-B= 0.009, P D-C= 0.006, P D-A= 0.597), permitting a full ECMO support in acardia by a peripheral vascular access. Conclusions: ECMO support in acardia is feasible, providing new opportunities in situations where heart must urgently be explanted, as in hyperacute rejection of heart transplant. Adequate drainage of pulmonary circulation is pivotal in order to avoid pulmonary congestion and loss of volume from the normal right to left shunt of bronchial vessels. Furthermore, the PA anastomosis to the caval axis not only improves pump flow but it also permits an ECMO support by a peripheral vascular access and the closure of the chest.

Biomedical risk assessment as an aid for smoking cessation.

BACKGROUND: A possible strategy for increasing smoking cessation rates could be to provide smokers who have contact with healthcare systems with feedback on the biomedical or potential future effects of smoking, e.g. measurement of exhaled carbon monoxide (CO), lung function, or genetic susceptibility to lung cancer. OBJECTIVES: To determine the efficacy of biomedical risk assessment provided in addition to various levels of counselling, as a contributing aid to smoking cessation. SEARCH STRATEGY: We systematically searched the Cochrane Collaboration Tobacco Addiction Group Specialized Register, Cochrane Central Register of Controlled Trials 2008 Issue 4, MEDLINE (1966 to January 2009), and EMBASE (1980 to January 2009). We combined methodological terms with terms related to smoking cessation counselling and biomedical measurements. SELECTION CRITERIA: Inclusion criteria were: a randomized controlled trial design; subjects participating in smoking cessation interventions; interventions based on a biomedical test to increase motivation to quit; control groups receiving all other components of intervention; an outcome of smoking cessation rate at least six months after the start of the intervention. DATA COLLECTION AND ANALYSIS: Two assessors independently conducted data extraction on each paper, with disagreements resolved by consensus. Results were expressed as a relative risk (RR) for smoking cessation with 95% confidence intervals (CI). Where appropriate a pooled effect was estimated using a Mantel-Haenszel fixed effect method. MAIN RESULTS: We included eleven trials using a variety of biomedical tests. Two pairs of trials had sufficiently similar recruitment, setting and interventions to calculate a pooled effect; there was no evidence that CO measurement in primary care (RR 1.06, 95% CI 0.85 to 1.32) or spirometry in primary care (RR 1.18, 95% CI 0.77 to 1.81) increased cessation rates. We did not pool the other seven trials. One trial in primary care detected a significant benefit of lung age feedback after spirometry (RR 2.12; 95% CI 1.24 to 3.62). One trial that used ultrasonography of carotid and femoral arteries and photographs of plaques detected a benefit (RR 2.77; 95% CI 1.04 to 7.41) but enrolled a population of light smokers. Five trials failed to detect evidence of a significant effect. One of these tested CO feedback alone and CO + genetic susceptibility as two different intervention; none of the three possible comparisons detected significant effects. Three others used a combination of CO and spirometry feedback in different settings, and one tested for a genetic marker. AUTHORS' CONCLUSIONS: There is little evidence about the effects of most types of biomedical tests for risk assessment. Spirometry combined with an interpretation of the results in terms of 'lung age' had a significant effect in a single good quality trial. Mixed quality evidence does not support the hypothesis that other types of biomedical risk assessment increase smoking cessation in comparison to standard treatment. Only two pairs of studies were similar enough in term of recruitment, setting, and intervention to allow meta-analysis.