Osteogenic protein-1 reduces intercellular adhesion molecule-1 messenger RNA expression,infarct size and TUNEL-positive cardiomyocytes in ischemia/reperfusion rat hearts

BACKGROUND:

Osteogenic protein, a member of the transforming growth factor-beta superfamily, has been reported to decrease the expression of intercellular adhesive molecules and prevent neutrophil accumulation and activity in tissue injury.

OBJECTIVE:

To examine the effects of osteogenic protein on ischemia/reperfusion in rat hearts.

METHODS:

Reperfusion was established after a 90 min ligation of the proximal left coronary artery in rats. Recombinant human osteogenic protein-1 (200 μg/kg) was administered via the femoral vein just before reperfusion. Intercellular adhesion molecule-1 (ICAM-1) messenger RNA (mRNA) expression and infarct size were evaluated using Northern blotting and triphenyl tetrazolium chloride staining, respectively. Terminal deoxynucleotidyl transferase mediated biotin-16-2′-deoxyuridine-5′-triphosphate nick end labeling (TUNEL) staining was also performed.

RESULTS:

In osteogenic protein-1 treated rats, the expression of ICAM-1 mRNA in ischemia/reperfusion hearts rapidly increased 4 h after reperfusion, although, the increase was lower than that observed in the vehicle-treated hearts (7.4±1.6-fold versus 14.6±3.7-fold increase compared to the increase observed in preligation control hearts, respectively). Similarly, in day 1 and day 7 hearts, the increase in ICAM-1 mRNA expression was significantly lower in ischemia/reperfusion hearts from rats treated with osteogenic protein-1 than in vehicle-treated rats (2.5±0.1-fold versus 5.8±2.3-fold and 1.5±0.3-fold versus 3.5±0.2-fold, respectively). Infarct size in rats treated with osteogenic protein-1 was significantly smaller than that observed in rats treated with vehicle (13.1±1.2% versus 28.5±5.7% of the left ventricle, P<0.01). The percentage of TUNEL-positive cardiomyocytes in ischemia/reperfusion hearts in rats treated with osteogenic protein-1 was significantly lower than in rats treated with vehicle (17.1±5.3% versus 31.1±4.5%, P<0.01).

CONCLUSION:

The present study demonstrated that recombinant human osteogenic protein-1 suppressed ICAM-1 mRNA expression, reduced infarct size and decreased TUNEL-positive cardiomyocytes in ischemic/reperfused rat hearts.     

Effects of Ischemic Postconditioning on the Hemodynamic Parameters and Heart Nitric Oxide Levels of Hypothyroid Rats

Background

Ischemic postconditioning (IPost) is a method of protecting the heart against ischemia-reperfusion (IR) injury. However, the effectiveness of IPost in cases of ischemic heart disease accompanied by co-morbidities such as hypothyroidism remains unclear.

Objective

The aim of this study was to determine the effect of IPost on myocardial IR injury in hypothyroid male rats.

Methods

Propylthiouracil in drinking water (500 mg/L) was administered to male rats for 21 days to induce hypothyroidism. The hearts from control and hypothyroid rats were perfused in a Langendorff apparatus and exposed to 30 min of global ischemia, followed by 120 min of reperfusion. IPost was induced immediately following ischemia.

Results

Hypothyroidism and IPost significantly improved the left ventricular developed pressure (LVDP) and peak rates of positive and negative changes in left ventricular pressure (±dp/dt) during reperfusion in control rats (p < 0.05). However, IPost had no add-on effect on the recovery of LVDP and ±dp/dt in hypothyroid rats. Furthermore, hypothyroidism significantly decreased the basal NO metabolite (NO_x) levels of the serum (72.5 ± 4.2 vs. 102.8 ± 3.7 μmol/L; p < 0.05) and heart (7.9 ± 1.6 vs. 18.8 ± 3.2 μmol/L; p < 0.05). Heart NO_x concentration in the hypothyroid groups did not change after IR and IPost, whereas these were significantly (p < 0.05) higher and lower after IR and IPost, respectively, in the control groups.

Conclusion

Hypothyroidism protects the heart from IR injury, which may be due to a decrease in basal nitric oxide (NO) levels in the serum and heart and a decrease in NO after IR. IPost did not decrease the NO level and did not provide further cardioprotection in the hypothyroid group.     

Increased QT dispersion and P wave dispersion in major depressive disorder

BACKGROUND:

QT and P wave dispersion parameters can indicate abnormalities in autonomic nervous system and cardiac functioning.

OBJECTIVES:

To determine QT and P wave dispersion in patients with major depressive disorder compared with healthy volunteers.

METHODS:

Fifty newly diagnosed patients with major depressive disorder and 50 age- and sex-matched healthy volunteers underwent 12-lead electrocardiography. QT interval, QT dispersion, heart rate-corrected QT dispersion and P wave dispersions were calculated manually by a blinded specialist.

RESULTS:

Groups were comparable in terms of age, sex, body mass index, smoking status, metabolic diseases and left ventricular ejection fraction. The major depressive disorder group had significantly higher QT dispersion (58.5±9.9 versus 41.7±3.8; P<0.001), heart rate-corrected QT dispersion (62.5±10.0 versus 45.2±4.3; P<0.001) and P wave dispersion (46.9±4.8 versus 41.5±5.1; P<0.001).

CONCLUSION:

Increased QT dispersion, heart-rate corrected QT dispersion and P wave dispersion in major depressive disorder patients may be indicative of autonomic imbalance and increased risk of cardiac morbidity and mortality.     

Evaluation of a novel method of teaching endobronchial ultrasound: Physician- versus respiratory therapist-proctored simulation training

BACKGROUND:

Computer endobronchial ultrasound (EBUS) simulators have been demonstrated to improve trainee procedural skills before attempting to perform EBUS procedures on patients.

OBJECTIVE:

To compare EBUS performance following training with computer simulation proctored by EBUS-trained respiratory therapists versus the same simulation training proctored by an interventional respirologist.

METHODS:

The present analysis was a prospective study of respiratory medicine trainees learning EBUS. Two cohorts of trainees were evaluated using a previously validated method using simulated cases with performance metrics measured by the simulator. Group 1 underwent EBUS training by performing 15 procedures on an EBUS simulator (n=4) proctored by an interventional respirologist. Group 2 received identical training proctored by a respiratory therapist with special training in EBUS (n=10).

RESULTS:

No significant differences between group 1 and group 2 were apparent for the primary outcome measures of total procedure time (15.15±1.34 min versus 14.78±2.88 min; P=0.816), the percentage of lymph nodes successfully identified (88.8±5.4 versus 80.91±8.9; P=0.092) or the percentage of successful biopsies (100.0±0.0 versus 98.75±3.95; P=0.549). The learning curves were similar between groups, and did not show an obvious plateau after 19 simulated procedures in either group.

DISCUSSION:

Acquisition of basic EBUS technical skills can be achieved using computer EBUS simulation proctored by specially trained respiratory therapists or by an interventional respirologist. There appeared to be no significant advantage to having an interventional respirologist proctor the computer EBUS simulation.     

Wet laboratory versus computer simulation for learning endobronchial ultrasound: A randomized trial

BACKGROUND:

Linear endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) is a revolutionary bronchoscopic procedure that is challenging to learn.

OBJECTIVES:

To compare two methods used to teach EBUS-TBNA: wet laboratory (lab) versus computer EBUS-TBNA simulation.

METHODS:

A prospective, randomized study of respirologists, thoracic surgeons and trainees learning EBUS-TBNA at a two-day continuing medical education course. All subjects received education via a series of lectures and live cases, followed by randomization to learn EBUS-TBNA predominantly either by wet lab simulation (n=6) or computer simulation (n=6). All subjects then completed testing of their EBUS-TBNA skills via a previously validated method using simulated cases on EBUS-TBNA simulators and questionnaires evaluating learner preferences.

RESULTS:

There were no significant differences between the computer EBUS-TBNA simulator group and the wet lab group in procedure time (25.3±6.1 min versus 25.2±2.5 min; P=0.984) and percentage of successful biopsies (81.3±14.9% versus 74.0±17.3%; P=0.453). The computer simulator group performed significantly better than the wet lab group in the percentage of lymph nodes correctly identified (70.4±16.7% versus 42.9±19.9%; P=0.002). Wet lab simulation was associated with increased learner confidence with operating the real EBUS-TBNA bronchoscope. All subjects responded that wet lab and computer EBUS-TBNA simulation offered important complementary learning opportunities.

DISCUSSION:

Computer EBUS-TBNA simulation leads to improved skill at correctly identifying lymph nodes, while wet lab simulation provided increased learner confidence due to increased realism.

CONCLUSION:

Computer EBUS-TBNA simulation and wet lab simulation are effective methods of learning basic EBUS-TBNA skills and appeared to be complementary.     

Enlargement of the aorta: An occupational disease?

BACKGROUND:

Aortic dilation may critically precede progression to thoracic aortic aneurysm (TAA). Prolonged or repetitive isometric-type heavier strenuous activities resulting from the nature of some professions may be an important causative factor for TAA.

METHOD:

The echocardiographic measurement data of middle-age subjects who were isometric-type daily strenuous activity trainers or ordinary activity trainers were retrospectively analyzed. Clinical features and echocardiographic parameters of the left ventricle and left atrium (LA), aortic root (AR) and ascending aorta (AA) were compared between the groups.

RESULTS:

AR (35.6±3.0 mm versus 33.5±1.9 mm), AA (36.8±3.0 mm versus 34.4±1.9 mm) and LA (37.4±2.2 mm versus 36.2±2.2 mm) diameters were significantly enlarged in the strenuous activity trainer group versus the ordinary activity group. Diastolic blood pressure was significantly lower (73.8±5.9 mmHg versus 78.3±6.0 mmHg) in this group. AR diameter was correlated with height (β=0.460; P=0.004) and LA diameter (β=0.280; P=0.008) while AA diameter was correlated with type of profession (β=0.309; P=0.003), left ventricular systolic diameter (β=0.500; P=0.001) and LA diameter (β=0.272; P=0.005) in regression analysis.

CONCLUSION:

Aortic dilation and, subsequently, TAA may be an occupational disease due to nature of some professions (eg, the military, security, weight lifters, athletes, heavy workers, etc). Echocardiography is a convenient method of imaging that could be easily applied either during preparticipation screening or during periodical examination of these subjects. Earlier detection of TAA and limitation of such strenuous activities in these individuals may be initial lifesaving measures for the prevention of future cases of aortic aneurysm and dissection.     

Effect of vitamin C supplementation on stroke recovery: A case-control study

Background and purpose:

Epidemiological studies have associated increased dietary intake of antioxidants (vitamin C, E, and β-carotene) in preventing and decreasing the extent of ischemic brain injury. The effect of vitamin C supplementation on functional recovery after stroke has not been studied.

Method:

In this retrospective, case-control study of 23 patients with ischemic stroke taking vitamin C were identified and matched for age, sex, onset to admission, and admission total functional independence measure (TFIM) with 23 patients with ischemic stroke not taking Vitamin C supplementation. Vitamin C 1000 mg daily was prescribed on admission to our unit mainly to patients who were undernourished (defined as significant weight loss and/or 90% or less ideal body weight for age and sex) and those with pressure sores. The outcome measures were: change in the TFIM, FIM-Cognition (FIM-Cog), and FIM-Motor sub-scores, discharge disposition, and length of stay (LOS).

Results:

The change in TFIM (20 ± 13 standard deviation [SD] vs. 26 ± 6, p = 0.20), FIM-Cog (3 ± 3 SD vs. 4 ± 5, p = 0.41), FIM-Motor (15 ± 11 SD vs. 20 ± 13, p = 0.21) sub-scores were less in the vitamin C treated group, but these differences did not reach statistical significance. Similarly, no significant differences were found in LOS (21 ± 9 SD vs. 23 ± 9, p = 0.59), and discharge disposition (home/institution) (9/10 vs. 13/9, p = 0.60) between the vitamin C and the control groups.

Conclusion:

This study suggests vitamin C supplementation did not enhance functional recovery in undernourished ischemic stroke patients.     

Wenxin Keli suppresses atrial substrate remodelling after epicardial ganglionic plexi ablation

BACKGROUND:

The chronic effects of ganglionic plexi (GP) ablation on atrial fibrillation (AF) inducibility have not been elucidated.

OBJECTIVE:

To investigate the effect of Wenxin Keli (WK) on the inducibility of AF and atrial substrate remodelling after epicardial GP ablation.

METHODS:

Twenty dogs were randomly divided into a sham-operated group, a GP ablation group and a WK-treated group. All animals underwent a left thoracotomy at the fourth intercostal space. AF inducibility was assessed by burst rapid pacing at the right atrium. Both the GP ablation group and the WK-treated group received four major GP ablations. In the WK-treated group, dogs were treated with oral WK once per day, and all animals were allowed to recover for eight weeks, after which AF inducibility and AF duration were measured again.

RESULTS:

After eight weeks of WK treatment, AF inducibility was lower than in the GP ablation group, and was similar to that of the sham-operated group. Compared with the sham-operated group, the levels of atrial natriuretic peptide (ANP), tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-6 in right atrial tissues were increased in GP ablation group (143.6±33.7 pg/mg versus 206.2±41.4 pg/mg, P=0.02; 75.3±12.1 pg/mg versus 141.3±64 pg/mg, P=0.03; and 175.1±42.5 pg/mg versus 351.7±101 pg/mg, P<0.01, respectively). There were no significant differences in levels of ANP, TNF-α and IL-6 in atrial tissues between the sham-operated group and WK treated group. Expression of connexin 43 in atrial tissues was increased after eight weeks of GP ablation, while WK administration inhibited connexin 43 remodelling.

CONCLUSIONS:

Epicardial GP ablation can induce atrial substrate remodelling, including Cx43 upregulation and increased levels of ANP, TNF-α and IL-6. These changes may be suppressed by long-term oral WK administration.     

Linking soluble vascular adhesion molecule-1 level to calcific aortic stenosis in patients with coronary artery disease

BACKGROUND:

Calcific aortic stenosis (AS) is an atherosclerosis-related process and the most common cause of valve disease requiring surgery.

OBJECTIVE:

To assess the association of inflammatory markers with AS in advanced atherosclerosis.

METHODS:

Consecutive patients with coronary artery disease (CAD) associated with AS were prospectively identified (mean transvalvular aortic gradient of 30 mmHg or greater). Subjects with aortic sclerosis (mean transvalvular aortic gradient of 10 mmHg or less) served as controls. All patients underwent clinical evaluation, echocardiography and coronary angiography.

RESULTS:

One hundred twenty-two patients with AS (85 men) and 101 with aortic sclerosis (76 men) of similar CAD severity were enrolled. The AS patients were older (mean [± SD] 71±7 years versus 66±7 years; P<0.001), had higher soluble vascular adhesion molecule-1 (s-VCAM-1) levels (1533±650 μg/L versus 1157±507 μg/L; P<0.001), but lower soluble intercellular adhesion molecule-1 (s-ICAM-1) (254±81 μg/L versus 293±84 μg/L; P<0.01) and soluble E-selectin (53±28 μg/L versus 62±29 μg/L; P<0.05) levels. The two groups did not differ with respect to C-reactive protein level (3±2.9 mg/L versus 3.4±2.6 mg/L; P not significant). Higher s-VCAM-1 (OR 1.09, 95% CI 1.04 to 1.14; P<0.001) and lower s-ICAM-1 (OR 0.82, 95% CI 0.72 to 0.94; P<0.001) levels were associated with AS after adjustment for age.

CONCLUSION:

Increased s-VCAM-1 levels were associated with calcific AS in patients with significant CAD.     

Left ventricular systolic and diastolic function in subjects with a bicuspid aortic valve without significant valvular dysfunction

BACKGROUND:

The bicuspid aortic valve (BAV) represents the most common cardiac congenital malformation in adults. It is frequently associated with dilation, aneurysm and dissection of the ascending aorta.

OBJECTIVE:

To evaluate left ventricular systolic and diastolic function in subjects with BAVs.

METHODS:

Thirty-five subjects with BAV (mean [± SD] age 25.9±5.7 years [range 17 to 36 years]; 18 male, 17 female) with either no valvular impairment or mild valvular impairment were recruited along with 30 control subjects (24.5±4.4 years of age [range 15 to 35 years]; 15 male, 15 female) who were matched for age, sex and body surface area. Left ventricular systolic and diastolic function were evaluated using conventional and tissue Doppler echocardiography. Left ventricular systolic and diastolic parameters were compared between the two groups.

RESULTS:

In subjects with BAVs, the ratio of mitral early diastolic velocity to late diastolic velocity was lower (0.95±0.4 versus 1.27±0.9; P=0.001), the ratio of mitral early diastolic velocity to myocardial early diastolic velocity was higher (10.1±3.2 versus 6.5±2.4; P=0.001) and the myocardial early diastolic velocity was lower (8.4±2.1 versus 15.3±3.6; P<0.001) compared with control subjects. In addition, the myocardial performance index was higher in subjects with BAVs than in control subjects (P=0.03). The left ventricular ejection fraction was also lower (53±11% versus 64±13%; P<0.001). No other statistically significant differences were observed between the two groups with regard to left ventricular systolic and diastolic parameters. In addition, the number of mitral valve prolapses and atrial septal aneurysms was higher in subjects with BAVs.

CONCLUSION:

BAVs may be associated with left ventricular systolic and diastolic dysfunction.     

Preclinical Study of a Biodegradable Polymer-based Stent with Abluminal Sirolimus Release

Background

Bioabsorbable polymer stents with drug elution only on the abluminal surface may be safer than durable polymer drug-eluting stents.

Objective

To report the experimental findings with the Inspiron^TM stent - a bioabsorbable polymer-coated stent with sirolimus release from the abluminal surface only, recently approved for clinical use.

Methods

45 stents were implanted in the coronary arteries of 15 pigs. On day 28 after implantation, angiographic, intracoronary ultrasonographic and histomorphological data were collected. Five groups were analyzed: Group I (nine bare-metal stents); Group II (nine coated with bioabsorbable polymer on the luminal and abluminal surfaces); Group III (eight stents coated with bioabsorbable polymer on the abluminal surface); Group IV (nine stents with bioabsorbable polymer and sirolimus on the luminal and abluminal surfaces); and Group V (ten stents with bioabsorbable polymer and sirolimus only on the abluminal surface).

Results

The following results were observed for Groups I, II, III, IV and V, respectively: percentage stenosis of 29 ± 20; 36 ± 14; 33 ± 19; 22 ± 13 and 26 ± 15 (p = 0.443); late lumen loss (in mm) of 1.02 ± 0.60; 1.24 ± 0.48; 1.11 ± 0.54; 0.72 ± 0.44 and 0.78 ± 0.39 (p = 0.253); neointimal area (in mm²) of 2.60 ± 1.99; 2.74 ± 1.51; 2.74 ± 1.30; 1.30 ± 1.14 and 0.97 ± 0.84 (p = 0.001; Groups IV and V versus Groups I, II and III); and percentage neointimal area of 35 ± 25; 38 ± 18; 39 ± 19; 19 ± 18 and 15 ± 12 (p = 0.001; Groups IV and V versus Groups I, II and III). Injury and inflammation scores were low and with no differences between the groups.

Conclusion

The Inspiron^TM stent proved to be safe and was able to significantly inhibit the neointimal hyperplasia observed on day 28 after implantation in porcine coronary arteries.     

Benefit of a low-fat over high-fat diet on vascular health during alternate day fasting

Background:

Alternate day fasting (ADF) with a low-fat (LF) diet improves brachial artery flow-mediated dilation (FMD). Whether these beneficial effects can be reproduced with a high-fat (HF) diet remains unclear.

Objective:

This study compared the effects of ADF-HF to ADF-LF regimens on FMD. The role that adipokines have in mediating this effect was also investigated.

Methods:

Thirty-two obese subjects were randomized to an ADF-HF (45% fat) or ADF-LF diet (25% fat), consisting of two phases: (1) a 2-week baseline weight maintenance period and (2) an 8-week ADF weight loss period. Food was provided throughout the study.

Results:

Body weight was reduced (P<0.0001) in the ADF-HF (4.4±1.0 kg) and ADF-LF group (3.7±0.7 kg). FMD decreased (P<0.05) by ADF-HF relative to baseline (7±1 to 5±2%) and increased (P<0.05) by ADF-LF (5±1 to 7±2%). Blood pressure remained unchanged in both groups. Adiponectin increased (P<0.05) in the ADF-HF (43±7%) and ADF-LF group (51±7%). Leptin and resistin decreased (P<0.05) in the ADF-HF (32±5% 23±5%) and ADF-LF group (30±3% 27±4%). Increases in adiponectin were associated with augmented FMD in the ADF-LF group only (r=0.34, P=0.03).

Conclusion:

Thus, improvements in FMD with ADF may only occur with LF diets and not with HF diets, and adipokines may not have a significant role in mediating this effect.     

Is the protection against ischemia induced by red wine linked to its antioxidant capacity?

OBJECTIVE:

To establish whether the total antioxidant capacity of nonalcoholic extracts of three Argentine red wines (RWE) is correlated with their protection against ischemia-reperfusion injury.

ANIMALS AND METHODS:

The antioxidant properties of three RWE were determined using different free radical-generating systems. To examine the effects of these RWE during a 20 min global ischemic period followed by 30 min of reperfusion, isolated rat hearts received 50 μg/mL of RWE 1 (cabernet-sauvignon), RWE 2 (malbec) or RWE 3 (a commercial mixture of cabernet-sauvignon, malbec and merlot) 10 min before and after ischemia. Left ventricular developed pressure (LVDP), maximal velocity of rise of left ventricular pressure (+dP/dt_max) and left ventricular end-diastolic pressure (LVEDP) were used to assess contractility and diastolic function.

RESULTS:

All RWE inhibited lipid peroxidation induced by the Cl₄C/NADPH system in a similar proportion (42±4%, 47±9% and 43±14% for RWE 1, RWE 2 and RWE 3, respectively). The scavenging activity of superoxide anion and 2,2-diphenyl-1-picryl-hydrazyl radical was about the same with the three RWE. In hearts without RWE treatment, LVDP and +dP/dt_max were 61±4% and 62±5%, respectively, at the end of the reperfusion period. Infusion of RWE 1 and RWE 2 significantly improved postischemic recovery (LVDP and +dP/dt_max were 102±4% and 101±4% for RWE 1 and 92±5% and 91±5% for RWE 2, respectively) and attenuated the increase of LVEDP. RWE 3 did not improve either systolic or diastolic dysfunction.

CONCLUSION:

These data show that although the three non-alcoholic RWE exhibit a similar total antioxidant capacity, only two of them protect the heart against myocardial stunning, suggesting that the protective effect is not primarily linked to the anti-oxidant properties of the extracts.     

Comparison of the effects of different magnesium administration times on infarct size

BACKGROUND:

The protection of high magnesium on infarct size remains controversial.

OBJECTIVE:

To examine the effects of magnesium administered before ischemia or early in reperfusion on infarct size in a rat model of global ischemia

METHODS:

Isolated rat hearts were submitted to 40 min of normothermic global ischemia and 2 h of reperfusion. After 20 min of stabilization, four protocols were performed: ischemic control (IC) hearts; 15 mM of magnesium chloride administered 15 min before ischemia (MgI); 15 mM of magnesium chloride administered during the first 15 min of reperfusion (MgR); or 15 mM magnesium plus 5 mM calcium (Mg+Ca) before ischemia. Infarct size was measured by triphenyltetrazolium staining. Contractile function was assessed by left ventricular developed pressure and the maximal velocity of rise of left ventricular presssure.

RESULTS:

The infarct size in IC hearts was 44±5%. In MgI and MgR hearts, the infarct diminished to 4.5±1.5% and 18±4%, respectively. In Mg+Ca hearts, the protection was also obtained (19±3%). Myocardial function also improved significantly by magnesium treatment. At the end of reperfusion, left ventricular developed pressure and maximal velocity of rise of left ventricular pressure values were 23±6% and 22±3% in MgI; and 10±3% and 9±2.6% in MgR versus 2±0.7% and 2.3±0.8% in IC hearts, respectively.

CONCLUSION:

The treatment with magnesium either before ischemia or early in reperfusion has an infarct size limiting effect in a model of global ischemia. This protective effect is partially due to its calcium antagonistic action.     

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.     

Functional Vascular Study in Hypertensive Subjects with Type 2 Diabetes Using Losartan or Amlodipine

Background

Antihypertensive drugs are used to control blood pressure (BP) and reduce macro- and microvascular complications in hypertensive patients with diabetes.

Objectives

The present study aimed to compare the functional vascular changes in hypertensive patients with type 2 diabetes mellitus after 6 weeks of treatment with amlodipine or losartan.

Methods

Patients with a previous diagnosis of hypertension and type 2 diabetes mellitus were randomly divided into 2 groups and evaluated after 6 weeks of treatment with amlodipine (5 mg/day) or losartan (100 mg/day). Patient evaluation included BP measurement, ambulatory BP monitoring, and assessment of vascular parameters using applanation tonometry, pulse wave velocity (PWV), and flow-mediated dilation (FMD) of the brachial artery.

Results

A total of 42 patients were evaluated (21 in each group), with a predominance of women (71%) in both groups. The mean age of the patients in both groups was similar (amlodipine group: 54.9 ± 4.5 years; losartan group: 54.0 ± 6.9 years), with no significant difference in the mean BP [amlodipine group: 145 ± 14 mmHg (systolic) and 84 ± 8 mmHg (diastolic); losartan group: 153 ± 19 mmHg (systolic) and 90 ± 9 mmHg (diastolic)]. The augmentation index (30% ± 9% and 36% ± 8%, p = 0.025) and augmentation pressure (16 ± 6 mmHg and 20 ± 8 mmHg, p = 0.045) were lower in the amlodipine group when compared with the losartan group. PWV and FMD were similar in both groups.

Conclusions

Hypertensive patients with type 2 diabetes mellitus treated with amlodipine exhibited an improved pattern of pulse wave reflection in comparison with those treated with losartan. However, the use of losartan may be associated with independent vascular reactivity to the pressor effect.     

Cardiac Surgery Costs According to the Preoperative Risk in the Brazilian Public Health System

Background

Heart surgery has developed with increasing patient complexity.

Objective

To assess the use of resources and real costs stratified by risk factors of patients submitted to surgical cardiac procedures and to compare them with the values reimbursed by the Brazilian Unified Health System (SUS).

Method

All cardiac surgery procedures performed between January and July 2013 in a tertiary referral center were analyzed. Demographic and clinical data allowed the calculation of the value reimbursed by the Brazilian SUS. Patients were stratified as low, intermediate and high-risk categories according to the EuroSCORE. Clinical outcomes, use of resources and costs (real costs versus SUS) were compared between established risk groups.

Results

Postoperative mortality rates of low, intermediate and high-risk EuroSCORE risk strata showed a significant linear positive correlation (EuroSCORE: 3.8%, 10%, and 25%; p < 0.0001), as well as occurrence of any postoperative complication EuroSCORE: 13.7%, 20.7%, and 30.8%, respectively; p = 0.006). Accordingly, length-of-stay increased from 20.9 days to 24.8 and 29.2 days (p < 0.001). The real cost was parallel to increased resource use according to EuroSCORE risk strata (R$ 27.116,00 ± R$ 13.928,00 versus R$ 34.854,00 ± R$ 27.814,00 versus R$ 43.234,00 ± R$ 26.009,00, respectively; p < 0.001). SUS reimbursement also increased (R$ 14.306,00 ± R$ 4.571,00 versus R$ 16.217,00 ± R$ 7.298,00 versus R$ 19.548,00 ± R$935,00; p < 0.001). However, as the EuroSCORE increased, there was significant difference (p < 0.0001) between the real cost increasing slope and the SUS reimbursement elevation per EuroSCORE risk strata.

Conclusion

Higher EuroSCORE was related to higher postoperative mortality, complications, length of stay, and costs. Although SUS reimbursement increased according to risk, it was not proportional to real costs.     

Capnography improves detection of apnea during procedural sedation for percutaneous transhepatic cholangiodrainage

BACKGROUND:

Capnography provides noninvasive monitoring of ventilation and can enable early recognition of altered respiration patterns and apnea.

OBJECTIVE:

To compare the detection of apnea and the prediction of oxygen desaturation and hypoxemia using capnography versus clinical surveillance during procedural sedation for percutaneous transhepatic cholangiodrainage (PTCD).

METHODS:

Twenty consecutive patients scheduled for PTCD were included in the study. All patients were sedated during the procedure using midazolam and propofol. Aside from standard monitoring, additional capnographic monitoring was used and analyzed by an independent observer.

RESULTS:

The mean (± SD) cumulative duration of apnea demonstrated by capnography was significantly longer than the mean cumulative duration of clinically detected apnea (207.5±348.8 s versus 8.2±17.9 s; P=0.015). The overall number of detected episodes of apnea was also significantly different (113 versus seven; P=0.012). There were 15 events of oxygen desaturation (decrease in oxygen saturation [SaO₂] ≥5%), which were predicted in eight of 15 cases by capnography and in one of 15 cases by clinical observation. There were three events of hypoxemia (SaO₂ <90%) that were predicted in three of three cases by capnography and in one of three cases by clinical observation.

CONCLUSION:

Capnographic monitoring was superior to clinical surveillance in the detection of apnea and in the prediction of oxygen desaturation during procedural sedation for PTCD.     

Assessment of the usefulness of video-assisted thoracoscopic surgery in patients with non-tuberculous thoracic empyema

Background

The purpose of this retrospective study was to investigate the effectiveness and the outcomes of video-assisted thoracic surgery (VATS) treatment and medical therapy (including chest tube drainage, antibiotic treatment) in empyema patients.

Methods

Thirty-two consecutive patients with thoracic empyema were treated by VATS or tube drainage from 2006 to 2011. An analysis reviewed outcomes between the operation group and the drainage group. In addition, the operation group was divided into two groups for analysis.

Results

The drainage period was 15.1±11.3 days in the drainage group and 8.3±4.6 days in the operation group. The length of hospital stay was 22.4±10.0 days in the drainage group and 16.3±5.0 days in the operation group. There were five in-hospital deaths in the drainage group, but no in-hospital deaths in the operation groups. In addition, patients in the early operation group had a significantly shorter hospital stay and postintervention drainage period than patients in the late operation group.

Conclusions

VATS for nontuberculous thoracic empyema was more effective than tube drainage and required a shorter hospital stay. The results also indicated that patients who receive early surgical treatment may show better outcomes with late surgical management.